Real Size Research Articles

Quantitative 3-T multi-parametric MRI and step-section pathology of recurrent prostate cancer patients after radiation therapy

ObjectivesDiagnosis of radio-recurrent prostate cancer using multi-parametric MRI (mp-MRI) can be challenging due to the presence of radiation effects. We aim to characterize imaging of prostate tissue after radiation therapy (RT), using histopathology as ground truth, and to investigate the visibility of tumor lesions on mp-MRI.MethodsTumor delineated histopathology slides from salvage radical prostatectomy patients, primarily treated with RT, were registered to MRI. Median T2-weighted, ADC, Ktrans, and kep values in tumor and other regions were calculated. Two radiologists independently performed mp-MRI-based tumor delineations which were compared with the true pathological extent. General linear mixed-effect modeling was used to establish the contribution of each imaging modality and combinations thereof in distinguishing tumor and benign voxels.ResultsNineteen of the 21 included patients had tumor in the available histopathology slides. Recurrence was predominantly multifocal with large tumor foci seen after external beam radiotherapy, whereas these were small and sparse after low-dose-rate brachytherapy. MRI-based delineations missed small foci and slightly underestimated tumor extent. The combination of T2-weighted, ADC, Ktrans, and kep had the best performance in distinguishing tumor and benign voxels.ConclusionsUsing high-resolution histopathology delineations, the real tumor extent and size were found to be underestimated on MRI. mp-MRI obtained the best performance in identifying tumor voxels. Appropriate margins around the visible tumor-suspected region should be included when designing focal salvage strategies. Recurrent tumor delineation guidelines are warranted.Key Points• Compared to the use of individual sequences, multi-parametric MRI obtained the best performance in distinguishing recurrent tumor from benign voxels.• Delineations based on mp-MRI miss smaller foci and slightly underestimate tumor volume of local recurrent prostate cancer.• Focal salvage strategies should include appropriate margins around the visible tumor.

An evaluation of the trade relationships between South Africa and China: An empirical review 1995–2014

South Africa’s (SA) largest trading partner is China. The bilateral trade flows between these two economies have been increasing since the end of the global financial crisis. There are several factors that determine the trade flows between these two economies. Research studies the impact of the real exchange rate, market size and economic size on the trade flows between SA and China, applying the gravity model of trade. Time series data for the period of 1995–2014 have been used and a multiple linear regression model was employed in the evaluation process. To determine the impact of the three underlying variables on the bilateral trade flows of SA and China, the ordinary least squares method was used. The explanatory variables consist of the product of SA’s gross domestic product (GDP) and China’s GDP, which act as the proxy for economic size, the product of South Africa’s population and China’s population, which act as the proxy for market size, and the real exchange rate between SA and China. Results revealed that the economic size and the market size have a strong positive impact on trade flows between SA and China and this is consistent with economic theory. On the other hand the real exchange rate has a negative impact on trade flows between SA and China. If two countries each have a large economic and population size trade, this results in high trade flows between the countries as compared to trading with smaller economies. Trade volume is also reduced if the countries trading have a highly volatile exchange rate. Based on the findings of the research, the article recommends that the Department of Trade and Industry should target trade with countries of big economic and market size. The research also shows that the absolute and comparative advantages are not the only basis of trade but other factors should be considered, such as exchange rate, economic size and market size. The central bank should maintain a stable exchange rate between the SA rand and partner countries’ currencies before trading. This enhances trade and leads to strong economic growth.

Congestion pricing policies: Design and assessment for the city of Rome, Italy

Congestion pricing is classified as a transportation demand management measure adopted to reduce impacts modern cities are suffering in terms of traffic congestion, road accidents and air and noise pollution. Such a measure allows linking road transport externalities directly to travelers producing them. The definition of proper tolling schemes enables this measure to act on demand short-term choices, forcing travellers to shift towards low impact road itineries (route diversion) and sustainable transport systems (modal diversion).This paper presents key findings in the design of pricing policies to a specific real size and complex case (city of Rome, Italy) addressing overall transport performances (on the multimodal network) and impacts (affecting the entire community), in a demand elastic context. Main contribution derives from equity matters dealt with in the impact assessment of pricing policies, so filling a gap not extensively studied in this field. Specifically, different tolling schemes have been defined from a quantitative (toll level) and spatial (city zones where pricing is implemented) viewpoint in order to guarantee equity aspects in the application of the measure: affected road users are limited to those travelling in city zones where the mass public transport network (metro and rail) is available; besides, the toll amount is related to the level of accessibility to public transport (whether only in origin/destination of the trip or in both).Results, evaluated adopting a simulation-based approach, are consistent with those obtained in other real world cases, and highlight that the adoption of a proper pricing policy in the city of Rome guarantees a demand diversion towards sustainable transport modes up to 25% for those zones directly involved by the pricing implementation; promising benefits have been observed even in a wider area, entire Province of Rome, not directly affected by the measure, in terms of reduction both of road users (up to 6%) and congestion costs (about 2%).

Prevalence and clinical characteristics of refractoriness to optimal proton pump inhibitor therapy in non-erosive reflux disease.

The real size of the gastro-oesophageal reflux disease (GERD) population not responding to proton pump inhibitor (PPI) therapy has still not been fully elucidated. Causes of PPI refractoriness include incorrect diagnosis and lack of adherence to therapy, in terms of incorrect dosage and timing. To evaluate the prevalence of refractoriness to optimal PPI therapy and the contribution of non-erosive reflux disease (NERD), reflux hypersensitivity, and functional heartburn, to PPI refractoriness. The association of functional GI symptoms in non-responders was evaluated. Frequency and severity of GERD symptoms (heartburn, regurgitation, chest pain), dysphagia, belching, epigastric pain, postprandial distress, irritable bowel syndrome (IBS), globus, and ear nose and throat (ENT) symptoms were evaluated in patients previously classified as non-responders. Patients with at least one of the oesophageal symptoms with a frequency ≥3 /week were treated with esomeprazole 40mg once daily for 8weeks and then re-evaluated. Non-responders (patients with oesophageal symptoms ≥3 times per week) underwent 24hour multichannel intraluminal impedance-pH monitoring. Of 573 consecutive patients, 92 with oesophageal symptoms and classified as PPI-refractory underwent the esomeprazole trial; 60 did not respond. IBS, epigastric pain, and post-prandial distress episodes were associated with a poor response on multivariate analysis. NERD, reflux hypersensitivity, and functional heartburn patients constituted 32%, 42%, and 26%, respectively of the PPI-refractory group. True refractoriness in patients with GERD symptoms attending a secondary care setting is lower than previously reported. Following a careful history and optimal PPI dosing, the rate of refractoriness was 20%. True NERD constitutes only a third of the PPI-refractory group.

Rocking curve and spatial coherence properties ofalong X-ray compound refractive lens.

Semi-analytical theory of a long set of X-ray compound refractive lenses (CRLs) based on recurrence relations is developed further. The geometrical aperture, angular divergence of incident radiation and source size were accurately taken into account. Using this theory it is possible to calculate the width of the rocking curve of a long (40.7 cm) Be CRL which coincides with experimental data obtained earlier. By this approach the transverse coherence length for the X-ray beam after passing a set of CRLs of arbitrary complexity has been estimated. It is shown that at the focus this coherence length is equal to a diffraction-limited beam size (beam size in the case of a point source) and has minimal difference with the real beam size.

Real-time rendering of computer-generated hologram with the view volume transformation based layered method

Abstract A layered rendering method for generating computer-generated hologram (CGH) of 3D objects based on view volume transformation is presented. The shape distortion and the size deviation of the 3D reconstructed image existing in conventional layer-based methods are avoided, and the reconstructed 3D image can preserve the real size of the original model with high quality. Real-time interaction with the digitally reconstructed holographic image with clear depth cues is experimentally demonstrated.

Pneumatic Atomization: Beam-Steering Correction in Laser Diffraction Measurements of Spray Droplet Size Distributions

Laser diffraction is among the most widely used methods for spray droplet size measurements. However, the so-called beam-steering effect must be considered when pneumatic atomizers are used for droplet generation. The beam-steering effect is a systematic measurement error, leading to the detection of apparent large spray droplets due to gradients in the refractive index of the gas phase. The established correction method is based on the reduction of the laser diffraction system’s measurement range by deactivation of detectors, relevant for the detection of large droplets. As this method is only applicable when size ranges of real and apparent droplet sizes are clearly different, an alternative method for beam-steering correction is introduced in the presented study. It is based on a multimodal log-normal fit of measured spray droplet sizes. The modality representing the largest droplets is correlated to the beam-steering effect and therefore excluded from the measured size distribution. The new method was successfully applied to previously published droplet size distribution measurements of an internal mixing Air-Core-Liquid-Ring (ACLR) atomizer. In measurements where the method of detector deactivation is applicable, excellent accordance of droplet size distributions, gained by both correction methods, was found. In measurements with overlapping real and apparent parts of the distribution, the new correction method led to a significant reduction of overestimated large droplets. As a consequence, we conclude that the new method presented here for beam-steering correction should be applied in laser diffraction measurements of spray droplet sizes, generated by pneumatic atomizers.

ATLAS “Baby-DEMO”

Abstract Evaporative CO 2 has been selected as the main detector cooling technology for the Phase II upgrade of the LHC silicon detectors at CERN. In order to provide input to the ATLAS Pixel TDR about the minimum attainable cooling temperature by the end of 2017, ATLAS, with a contribution of CMS, has launched a dedicated detector cooling R&D study nick-named Baby-DEMO. The Baby-DEMO is the demonstration of a typical 2PACL CO 2 cooling plant operating at the lowest temperature ever achieved. A real size ATLAS mock-up is used to hold realistic manifolding as its critical path might have strong impact on the cooling performance. Additionally, the “Baby-DEMO” program addresses the study of high power flexible vacuum insulated coaxial transfer lines and warm nose boiling enhancement as possible solutions for the Phase II upgrade. This paper describes the system design including CO 2 plant, primary chiller and typical distribution. Challenges and solutions used to achieve the lowest possible evaporation temperatures are reported. The result of this study, even if at the preliminary stage, are of great interest for the design of the cooling systems that ATLAS and CMS will use in the Phase II era.

Application of a Log Likelihood Object In GARCH with T-distributed errors and EGARCH With Generalised Error Distribution Model of the Spot AUD/USD Exchange Rate Volatility.

In this article, we have tested the volatility of the returns of the spot exchange rate of AUD/USD for changing conditional variances by using a log likelihood model. Generalized autoregressive conditional heteroskedastic models, (GARCH) with t-distributed errors, and exponential generalized autoregressive conditional heteroskedastic model, (EGARCH) with generalised error distribution take into account the non-linearity that arises in the financial time series. The aim is to compare and select the maximum value of the log likelihood estimation of the AUD/USD spot exchange rate. The log likelihood model take into account autoregressive, (AR), moving average, (MA), and monthly seasonal moving average, (SMA) factors that could better explain volatility clusters. We have selected the model with the best forecasting ability in terms of the lowest value of the Akaike information criterion, the Schwarz criterion, the Hannan – Quinn criterion. The best model will help the arbitrageurs to better craft their investment strategy in terms of holding, buying or selling portfolios of foreign currencies. The software that we have used is EViews 6. We have concluded that the best fit model is the GRACH model with a t-distribution, as it has the maximum log likelihood estimation of -500.354. The average log likelihood is -1.81. The Akaike information criterion, the Schwarz criterion and the Hannan – Quinn criterion have the lowest error estimates. Their values are 3.60, 3.56 and 3.59 respectively. In terms of gradients at the estimated parameters, we have found that there are outlier values and significant fluctuations at the various observations of the coefficients vectors, C(1), C(2), and C(3) of the gradients. Finally, the analytic derivatives were calculated based on the specified values. The real and minimum step sizes are identical for all coefficients vectors and very close to zero. We have used one-sided numeric derivative. The data that we have used are monthly returns starting from 01/01/1990 to 01/01/2013, which total to 276 observations. The total dataset includes 277 observations. The data was obtained from the Federal Reserve Statistical Release Department and the symbol of the series is H.10.

Application of a Log Likelihood Object of An ARMA Model of Well – Known Closed – End Funds of Major Investment Banks.

In this article, we have applied an autoregressive moving average, ARMA(2,2) model of order AR(1), AR(2), MA(1), MA(2) and SMA(12) to test the natural logarithmic monthly market returns of the of the closed – end funds of major investment banks such as Van Kampen income trust, Aberden Asia Pacific income fund, Credit Suisse asset management income, Scudder high income and Templeton global income. The purpose of this article is to eliminate the seasonality, to compare and select the maximum value of the log likelihood estimation of the different closed-end funds. We have selected the model with the best forecasting ability in terms of the lowest value of the Akaike information criterion, the Schwarz criterion, the Hannan – Quinn criterion. The software that we have used is EViews 6. We have found that the natural logarithmic monthly market price returns of all closed-end funds are a stationary series. We have concluded that the best fit model is Scudder high income, (LNMPSHI), closed-end fund as it has the maximum log likelihood value of -123.16 and the Akaike information criterion, the Schwarz criterion, and the Hannan – Quinn criterion are 1.65, 1.55 an 1.61 respectively. In terms of gradients at the estimated parameters, we have found that there are outlier values and significant fluctuations at the various observations of the coefficients vectors, C(1), C(2), C(3), C(4) and C(5) of the gradients. The gradients of the log likelihood function have been computed at the estimated parameters and the unsuccessful estimation are displayed through the outliers of the peak of the graph of the four closed-end funds. Credit Suisse asset management income, (LNMPCS), closed-end fund displayed less outlier values and not significant fluctuations at the various observations of the coefficients vectors, C(1), C(2), C(3), C(4) and C(5) of the gradients. Finally, the analytic derivatives were calculated based on the specified values. The real and minimum step sizes are identical for all coefficients vectors and very close to zero. We have used one-sided numeric derivative. The whole dataset is from 31/01/1990 to 31/12/2001. The total observations are 144 and the logarithmic monthly market returns observations are 143.The data was obtained from Thomson Financial Investment View database.

Solution of the Problem of Empty Car Distribution between Stations and Planning of Way-Freight Train Route Using Genetic Algorithms

In this paper we consider the problem of distributing empty freight cars in a railway polygon. We show how the process can be improved using an optimization model. The optimization model can be characterized as a combination of minimum-cost flow problem with vehicle routing problem. In general, problem of empty railroad car distribution between stations and definition of way-freight train route is presented as integer combinatorial optimization problem. Computational tests show that the model can be solved in acceptable time for real size problems, and indicate that the model generates distribution plans that can improve the quality of the planning process.

Real class sizes

In this paper, we study the structures of finite groups using some arithmetic conditions on the sizes of real conjugacy classes. We prove that a finite group is solvable if the prime graph on the real class sizes of the group is disconnected. Moreover, we show that if the sizes of all noncentral real conjugacy classes of a finite group G have the same 2-part and the Sylow 2-subgroup of G satisfies a certain condition, then G is solvable.

Enhancement of solar energy collection with magnetic nanofluids

Nowadays, energy crisis has caused widespread concerns about sustainable energy. Solar energy, as sustainable, renewable energy, has attracted many attentions. Compared to other solar energy utilizations, solar collectors are more efficient and commercial devices to collect solar energy. In our present study, well-dispersed magnetic nanofluids (MNFs) are reported that they exhibit excellent optical thermal conversion performance under the suitable magnetic intensity and direction. In this work, the colloidal stability of MNFs was improved by controlling pH within neutral value. One kind of surface modifications, oleic acid, was carried out to enhance the interaction between particles and surfactants. The hydrodynamic diameter was found to be very close to the real size of particle. Meanwhile, a highly efficient solar collection system was built based on controlling the optical thermal performance of MNFs by magnetic fields. The experimental results showed that the thermal efficiency of solar collectors increased with MNFs. The thermal efficiency of MNFs is much higher than base liquid with the concentration of only 0.05 vol.%. Moreover, in the presence of the external magnetic field, the solar collector efficiency increases to the maximum, 25% higher than the conventional parabolic trough and 12% higher than the selective surface absorber. The study indicates that MNFs, even of low-content, have good absorption of solar radiation, and can improve the outlet temperatures and system efficiencies. All these studies show the potential of MNFs in solar thermal conversion applications.

Call and be counted! Can we reliably estimate the number of callers in the indri's (Indri indri) song?

Estimating the number of animals participating in a choral display may contribute reliable information on animal population estimates, particularly when environmental or behavioral factors restrict the possibility of visual surveys. Difficulties in providing a reliable estimate of the number of singers in a chorus are many (e.g., background noise masking, overlap). In this work, we contributed data on the vocal chorusing of the indri lemurs (Indri indri), which emit howling cries, known as songs, uttered by two to five individuals. We examined whether we could estimate the number of emitters in a chorus by screening the fundamental frequency in the spectrograms and the total duration of the songs, and the reliability of those methods when compared to the real chorus size. The spectrographic investigation appears to provide reliable information on the number of animals participating in the chorusing only when this number is limited to two or three singers. We also found that the Acoustic Complexity Index positively correlated with the real chorus size, showing that an automated analysis of the chorus may provide information about the number of singers. We can state that song duration shows a correlation with the number of emitters but also shows a remarkable variation that remains unexplained. The accuracy of the estimates can reflect the high variability in chorus size, which could be affected by group composition, season and context. In future research, a greater focus on analyzing frequency change occurring during these collective vocal displays should improve our ability to detect individuals and allow a finer tuning of the acoustic methods that may serve for monitoring chorusing mammals.

Defect analysis and fatigue design basis for Ni-based superalloy 718 manufactured by selective laser melting

It is well known that high strength metallic materials with Vickers hardness HV > 400 are very sensitive to small defects. This paper discusses fatigue properties of a Ni-based Superalloy 718 with HV = ∼470 manufactured by additive manufacturing (AM). The advantage of AM has been emphasized as the potential application to high strength or hard steels which are difficult to manufacture by traditional machining to complex shapes. However, the disadvantage or challenge of AM has been pointed out due to defects which are inevitably contained in the manufacturing process.Defects of the material investigated in this study were mostly gas porosity and those made by lack of fusion. The successful application of the area parameter model was confirmed. Although the statistics of extremes analysis is useful for the quality control of AM, the particular surface effect on the effective value of defect size must be carefully considered. Since the orientations of defects in AM materials are random, a defect in contact with specimen surface has higher influence on fatigue strength than an internal defect and has the effective larger size termed as areaeff than the real size, area, of the defect from the viewpoint of fracture mechanics. The guide for the fatigue design and development of higher quality Ni-based Superalloy 718 by AM processing based on the combination of the statistics of extremes on defects and the area parameter model is proposed.

The impact of breast MRI workup on tumor size assessment and surgical planning in patients with early breast cancer.

The size and focality of the primary tumor in breast cancer (BC) influence therapeutic decision making. The purpose of this study was to evaluate whether preoperative breast magnetic resonance imaging (MRI) is helpful for the assessment of tumor size and surgical planning in early BC. We performed a retrospective review of a prospectively collected database of 174 patients treated at a single institution for invasive BC who had complete documentation of the tumor size from mammography (MMG), ultrasonography (US), and MRI. A total of 186 breast tumors were analyzed. Mean tumor size varied by imaging method: 14.7mm by MMG, 13.8mm by US, and 17.9mm by MRI. The concordance between breast imaging techniques (BIT) and final pathology with a cutoff≤2mm was 34.8% for MRI, 32.1% for US, and 27.2% for MMG. US and MMG underestimated while MRI and MMG overestimated the real tumor size. Concordance was the same in premenopausal women for MRI and US at 35%, while concordance was higher in postmenopausal women for MRI. Correlations between size determined by BIT and histopathological size were best with MRI (0.59), compared to US (0.56) or MMG (0.42). Intrinsic subtypes of BC had different concordances according to imaging method, but no significant associations were found. MRI examination revealed additional lesions in 13.8% of patients, 69% of these lesions were malignant. MRI changed the surgical plan in 15 patients (8.6%), and the rate of mastectomy increased by 6.9%. MRI estimates BC tumor size more accurately than US or MMG, but a significant overestimation exists. Complementary MRI examination improved the concordance for tumor size between BIT and final pathology in 16.7%. MRI did not alter surgical planning for most patients and allowed more appropriate treatment for 8% of them.

Real-time geometric fitting and pose estimation for surface of revolution

This paper presents a novel ellipse fitting method to simultaneously estimate the Euclidean pose and structure of a surface of revolution (SOR) by minimizing the geometric reprojection error of the visible cross sections in image space. This geometric error function and its Jacobian matrix are explicitly derived to enable Levenberg-Marquardt (LM) optimization. With the obtained pose and structure, the Euclidean shape of a SOR can be reconstructed by generating the ellipse tangency to the apparent contour of the SOR. Given the real size of several visible cross sections, this approach can be extended to perform a real-time 3D tracking of the SOR. Additionally, this technique can be also generalized to fitting for imaged parallel circles. Sufficient experiments validate the accuracy and the real-time performance of the proposed method.

Interactions between micro-scale oil droplets in aqueous surfactant solution determined using optical tweezers

HypothesisThe stability of the emulsions is crucial, which relies on a well-developed understanding of dynamic interaction forces between single dispersed droplets. In the previous studies, many interests focus on the oil droplets of size range of 20–200 µm. However, emulsion droplets with diameter below 10 µm are rarely mentioned, which is the size scale of real emulsion droplets in various applications, such as toners, spacers for liquid crystal displays, and materials in biomedical and biochemical analysis. The micro-scale droplets have many differences on the deformation, internal pressure and hydrodynamic effects. It is necessary to understand the interaction mechanisms between two real size scales of oil droplets for guiding practical production and application. ExperimentsIn this work, tetradecane was chosen as the model oil phase in all experiments. The interaction forces of two tetradecane droplets with the diameter of 5.0 µm in water in the presence of surfactant and salt solution were directly measured using optical tweezers. The force-distance curves were established, and the zeta potential of tetradecane droplets was studied using Zetasizer Nano ZSP. FindingsThe absolute value of zeta potential of tetradecane droplets was found to decrease with the increase of salt concentration and increase with the increase of surfactant concentration. The repulsive force between two tetradecane droplets was found to decrease with the increase of salt concentration because the electrostatic double-layer force was suppressed gradually with the increase of salt concentration. The “hydrodynamic suction” effect during the process of retraction becomes more pronounced due to the corresponding increase in the hydrodynamic force with the increase of the approaching velocity between the tetradecane droplets. Furthermore, we found the existing model for the measurement of large droplets by atomic force microscope (AFM) is invalid for the measurement of micro-scale droplets by optical tweezers. The deformation of colliding micro-scale droplets can be safely ignored, which is quite different from the large droplets. Our results provide a useful method to study the interaction forces between micro-scale emulsion droplets with pN force resolution, and gives a deep insight of the stabilization mechanism of real size scale of O/W emulsions. These findings have significant implications on the stability of emulsions in many food, cosmetics, medicine, and advanced materials.

Novel encapsulant architecture on the road to photovoltaic module power output increase

Nowadays, non-silicon materials on photovoltaic modules represent near half of its final price. Therefore, actions focused on photovoltaic module material reduction, as well as final photovoltaic module power increment, will have positive impacts on the factory annual economic balance. In this work, we propose a novel ethylene-vinylacetate (EVA) encapsulant architecture, which allows an excellent light management without any change in the production line. It is based on the enlargement of the solar radiation spectral range reaching the cell by the use of a low ultraviolet cut off EVA as a front encapsulant, and an original White EVA as a rear encapsulant film, which promotes the radiation reflectance by the free-silicon area inside of the module. Real size photovoltaic modules with this encapsulant design have been fabricated in an automatic line and the highest power increment measured is 5.16 W. This implies a valuable improvement on the power distribution of a photovoltaic module production line. These photovoltaic modules have also successfully overcome the most common aging tests.

Complete hierarchical multi-objective genetic algorithm for transit network design problem

Transit Network Design Problem is a multi-disciplinary problem that is considered one of the most intractable problems for real size networks. In the late 90s, Meta-heuristics started to prove more reliability to the problem. Genetic Algorithm (GA) is one of the popular Meta-heuristics which is usually implemented because it is simply adapted to the problem. In this study, GA is presented as a complete constructive multi-objective algorithm that creates its own routes from scratch then assembles the routes into efficient transit networks. Finally, it handles the multi-criteria nature of the problem until producing the optimal (near optimal) Pareto front solutions. A new frequency setting algorithm is also developed based on simulation results at the bus stop level which takes the bi-level decision making of both users and operators implicitly. Experimental studies on two real size networks are conducted to validate the methodology performance and robustness.