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• The Castillo-Canteli model is extended to probabilistic evaluation of LCF data. • GR V M = ψ σ M where ψ is a non-dimensional factor derived from the σ - ε curve. • The stress- and strain –based approaches are joined to a unified ψ σ M -based approach. • The ψ σ M concept is applied as the ψ σ M - R - N model to include stress ratio effect. • The model is successfully applied to the experimental campaigns of three materials. New advances in the probabilistic S-N model proposed by Castillo and Canteli are presented. The requirements for a S-N model derivation to be valid are emphasized, in particular, that of the compatibility between the statistical distributions of lifetime and stress reference variable. The definition of the generalized reference variable (GRV) in the S-N field, as GRV = ψ · σ M , where ψ is a non-dimensional factor derived from the σ - ε law of the material, allows the former model to be applied to LCF data. The new model ensures the incontrovertible and unitary definition of the scatter band in the S-N field and the justification of an asymptotic lower limit of the lifetime, N 0. As a result, the stress- and strain-based approaches can be envisaged as a unique probabilistic ψ σ M - N approach applicable in the three conventional, i.e., LCF, HCF and VHCF domains. An extension as the ψ σ M - R - N model that includes the stress ratio effect is presented. The utility of the model is confirmed with the assessment of LCF data from different external experimental campaigns. [ABSTRACT FROM AUTHOR]

Methods have been developed that apply image processing to 4DCTs to generate lung ventilation maps (4DCT-ventilation). 4DCT-ventilation provides functional information without burdening the patient with an extra imaging procedure. Traditional 4DCT-ventilation methods that rely on Hounsfield-Unit (HU) density-change lack reproducibility and do not provide 4DCT-perfusion data. Novel 4DCT-ventilation/perfusion methods have been developed that are robust and provide the perfusion information. The purpose of this study was to use prospective clinical trial data to evaluate the most effective 4DCT-based lung function imaging method for predicting radiation pneumonitis (RP). 63 advanced-stage lung cancer patients enrolled in a multi-institutional, phase 2 clinical trial on 4DCT-based functional avoidance radiation therapy were used. 4DCT- were used to generate 4 lung function images: 1) 4DCT-ventilation using the traditional HU ('4DCT-vent-HU') approach, and 3 methods using the novel statistically robust methods: 2) 4DCT-ventilation based on the Mass Conserving Volume Change ('4DCT-vent-MCVC'), 3) 4DCT-ventilation using the Integrated Jacobian Formulation ('4DCT-vent-IJF') and 4) 4DCT-perfusion. For each 4DCT-ventilation/perfusion image, dose-function metrics were calculated including mean functional lung dose (fMLD), and percentage of functional lung volume receiving ≥ 5Gy (fV5), and ≥ 20Gy (fV20). The ability of standard lung dose metrics (MLD and V20) and dose-function metrics derived from the 4DCT-ventilation/perfusion imaging modalities to predict for ≥ grade 2 RP was assessed using univariate logistic regression and machine learning. Model performance was evaluated using the area under the curve (AUC) and validated through 10-fold cross-validation (CV). 10/63 (15.9%) patients developed grade ≥2 RP. Logistic regression analysis yielded mean AUCs of 0.70 ± 0.02 (P = 0.04), 0.64 ± 0.04 (P = 0.13), 0.60 ± 0.03 (P = 0.27), 0.63 ± 0.03 (P = 0.20), and 0.64 ± 0.08 (P = 0.38) for 4DCT-vent-MCVC, 4DCT-perfusion, 4DCT-vent-IJF, 4DCT-vent-HU, and standard lung metrics, respectively. Machine learning modeling with 10-fold CV resulted in AUC values of 0.86 ± 0.07, 0.83 ± 0.08, 0.78 ± 0.07, 0.75 ± 0.08, and 0.78 ± 0.08 for the 4DCT-vent-MCVC, 4DCT-perfusion, 4DCT-vent-IJF, 4DCT-vent-HU, and standard lung metrics, respectively. fMLD and fV20 exhibited the highest feature overlap in predicting RP. This is the first study to comprehensively evaluate 4DCT-perfusion and robust 4DCT-ventilation in predicting RP outcomes. Our data identified 4DCT-ventilation based on the MCVC formulation along with fMLD and fV20 as the best predictors of RP; outperforming both standard lung metrics and traditional 4DCT-ventilation formulations. These findings will inform the design of phase III clinical trials and the optimal incorporation of 4DCT-ventilation/perfusion into thoracic radiotherapy clinical practice for reduced toxicity. [ABSTRACT FROM AUTHOR]

Pei cn1ospora bell)ahrii is an ooniyeete and the cause of basil downy mildew. one of the most destructive diseases affecting basil production worldwide. Disease management is challenging due to wind-dispersed sporangia and contaminated seed; therefore. identifying P. belbahrii in seed lots before sale or planting or in the field before .symptoms develop could allow for timely deployment of disease management strategies. In this study. a draft cultigenome assembly and next - generation sequencing leads for P, belbahrii. as well as publicly available DNA-seq und RNA-seq reads of several other downy mildew pathogens. were incorporated into a bioinformatics pipeline mitito piedict P. belbahrii-specific diagnostic markers, The specificity of' each candidate marker was validated against a diverse DNA collection of P. belbahrii, host tissue. and related oomycetes using PCR. Two species - specific markers were identified and used as templates to develop a highly sensitive probe - based real - time quantitative PCR( qPCR) assay that could detect P. belbahrii in leaf tissue and seed samples. Both markers were capa - ble of reliably detecting as low as 500 fg/F/of P. belbahrii genomic DNA and as few as 10 sporangia. The qPCR assay was then validated with seed samples collected from a basil cultivar experiment. In total. 48 seed samples were collected and tested; P. belbahrii was detected in samples of all cultigenome vars at estimated concentrations of 600 fg/pl up to 250 pg/gl and at as few as 10 sporangia up to >1.()00 sporangia. The markers and assays are valuable for diagnostics and identifying P. belb, 1/71-ii-contaminated seed lots to mitito gate the effects of future basil downy mildew epidemics. [ABSTRACT FROM AUTHOR]

• First, second, and third order BDF schemes are assessed for the numerical approximation of thermally coupled flows. • The BDF schemes are numerically tested for different Richardson numbers in the range 0

• The effect of rheological behavior of power-law fluids is evaluated numerically in confined and non-confined cases. • The Hopf bifurcation is defined for different blockage ratios and for different power-law fluids. • The effect of the power-law index on the promotion of mixing capacity in the flow is evaluated in 2D and 3D cases. • All numerical cases are solved using a recently proposed stabilized finite element method. • Numerical results can be used to understand more complex fluids under confinement and blockage conditions. In this work, the rheological behavior of power-law fluids on the flow dynamics is studied numerically. Studied cases include confined and non-confined problems that involve a single and two cylinders in tandem for 2-D and 3-D. For 2-D cases, the critical Reynolds numbers that define the Hopf bifurcation and its relation between the blockage ratio and the nature of the fluid are analyzed, including a complete CFD analysis. Results show that the blockage ratio, the addition of a second cylinder, and the rheological properties directly influence the flow's behavior. In this respect, the critical Reynolds number decreases by decreasing the power-law index and increasing the blockage ratio using shear-thinning fluids, and by increasing the power-law index in unconfined cases of shear-thickening fluids. For the 3-D case, different fluids are compared for a fixed Reynolds number and blockage ratio, proving that pseudoplastic fluids increase mixing capacity. [ABSTRACT FROM AUTHOR]

The modeling of turbulent flows is relevant in many engineering applications and, is an active field of research on numerical methods. Convergence and stability of proposed formulations are crucial to predict transitional flows from laminar to turbulent flows. In this work, a recently developed stabilized finite element formulation is used as a powerful tool to describe such kind of problems. The essential point of the formulation is the time dependent nature of the subscales and, contrary to residual based formulations, the introduction of two velocity subscale components. The theoretical rate of convergence of the method is verified numerically using linear and quadratic equal-order finite element discretizations. To this end, a standard convergence test of L 2 -norm is presented where the computed solutions are compared when manufactured solutions are imposed at Gauss-point level. Moreover, the Hopf bifurcation is studied for two well-known benchmark problems: flow past a cylinder and the three-dimensional lid-driven cavity flow. For the flow past a cylinder case, the Hopf bifurcation is verified using dynamic subscales and is assessed so that they do not disturb the solution. In particular, a dominant convective problem (Re = 4000) is solved using both the quasistatic and dynamic versions of the method, evaluating the performance of each one in the quality of the solution and in the CPU time needed to obtain a converged solution. For the 3D lid-driven cavity flow problem, the Hopf bifurcation is determined using two different boundary conditions, analyzing their effect on the dynamics of the problem and on the thickness and shape of the boundary layer. The final test case is the turbulent 3D lid-driven cavity problem (Re = 12000), where velocity profiles are compared with experimental, LES and DNS reference solutions. Additionally, pressure and velocity spectra are shown at certain representative points of the domain, as well as phase diagrams, correlation function graphs, the Poincaré map, and the Lyapunov exponent, typical mathematical tools used in dynamical system analysis. From the results, the method is robust and accurate for all the numerical tests both in viscous dominant problems as in dominant convective ones. • A non-residual VMS finite element formulation is proposed to solve convective dominant problems. • The rate of convergence of the method is verified numerically for linear and quadratic elements. • The effect of the inclusion of the time dependent nature of the subscales is evaluated numerically. • 2D and 3D benchmark problems are solved to check accuracy and robustness of the formulation. [ABSTRACT FROM AUTHOR]

Pseudoperonospora humuli is an obligate oomycete pathogen of hop (Humulus lupulus) that causes downy mildew, an important disease in most production regions in the Northern Hemisphere. The pathogen can cause a systemic infection in hop, overwinter in the root system, and infect propagation material. Substantial yield loss may occur owing to P. humuli infection of strobiles (seed cones), shoots, and cone-bearing branches. Fungicide application and cultural practices are the primary methods to manage hop downy mildew. However, effective, sustainable, and cost-effective management of downy mildew can be improved by developing early detection systems to inform on disease risk and timely fungicide application. However, no species-specific diagnostic assays or genomic resources are available for P. humuli. The genome of the P. humuli OR502AA isolate was partially sequenced using Illumina technology and assembled with ABySS. The assembly had a minimum scaffold length of 500 bp and an N50 (median scaffold length of the assembled genome) of 19.2 kbp. A total number of 18,656 genes were identified using MAKER standard gene predictions. Additionally, transcriptome assemblies were generated using RNA-seq and Trinity for seven additional P. humuli isolates. Bioinformatics analyses of next generation sequencing reads of P. humuli and P. cubensis (a closely related sister species) identified 242 candidate species-specific P. humuli genes that could be used as diagnostic molecular markers. These candidate genes were validated using polymerase chain reaction against a diverse collection of isolates from P. humuli, P. cubensis, and other oomycetes. Overall, four diagnostic markers were found to be uniquely present in P. humuli. These candidate markers identified through comparative genomics can be used for pathogen diagnostics in propagation material, such as rhizomes and vegetative cuttings, or adapted for biosurveillance of airborne sporangia, an important source of inoculum in hop downy mildew epidemics. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we propose and analyze the stability and the dissipative structure of a new dynamic term-by-term stabilized finite element formulation for the Navier–Stokes problem that can be viewed as a variational multiscale (VMS) method under some assumptions. The essential point of the formulation is the time dependent nature of the subscales and, contrary to residual-based formulations, the introduction of two velocity subscale components. They represent the components of the convective and the pressure gradient terms, respectively, of the momentum equation that cannot be captured by the finite element mesh. A key idea of the proposed method is that the convective subscale is close to a solenoidal field and the pressure gradient subscale is close to a potential field. The method ensures stability in anisotropic space–time discretizations, which is proved using numerical analysis for a linearized problem and demonstrated in classical numerical tests. The work includes a detailed description of the proposed formulation and several numerical examples that serve to justify our claims. Highlights • A new dynamic term-by-term stabilized finite element formulation is proposed. • The proposed method ensures stability in anisotropic space–time discretizations. • The dissipative structure of the method is analyzed and some stability results are presented. • Several numerical examples are presented to justify our claims. [ABSTRACT FROM AUTHOR]

In this work, a variational multiscale finite element formulation is used to approximate numerically the lid-driven cavity flow problem for high Reynolds numbers. For Newtonian fluids, this benchmark case has been extensively studied by many authors for low and moderate Reynolds numbers (up to Re = 10 , 000 ), giving place to steady flows, using stationary and time-dependent approaches. For more convective flows, the solution becomes unstable, describing an oscillatory behavior. The critical Reynolds number which gives place to this time-dependent fluid dynamics has been defined over a wide range 7, 300 ≲ Re ≲ 35, 000, using different numerical approaches. In the non-Newtonian case, the cavity problem has not been studied deeply for high Reynolds number (Re > 10, 000), specifically, in the oscillatory time-dependent case. A VMS formulation is presented to be validated using existing results, to determine flow conditions at which the instability appears, and lastly, to establish new benchmark solutions for high-Reynolds numbers fluid flows using the power-law model. Obtained results show a good agreement with those reported in the references, and new data related with the oscillatory behavior of the flow has been found for the non-Newtonian case. In this regard, time-dependent flows show dependence on both Reynolds number and power-law index, and the unsteady starting point has been determined for all studied cases. It is determined that the critical Reynolds number (Re c ) that defines the first Hopf bifurcation for Newtonian fluid flow is ranged between 8,100 ≲ Re c  ≲ 8, 250, whereas for power-law indexes n = 0.5 and n = 1.5 , it is 7,100 ≲ Re c  ≲ 7,200 and 18,250 ≲ Re c  ≲ 18,500, respectively. [ABSTRACT FROM AUTHOR]

This paper proposes some corrections and comments to the BCD multiplier presented in the paper “Fast architecture for decimal digit multiplication”, published in the Journal of Microprocessors and Microsystems (Volume 39, 2015, issues 4–5, pages 296–301). Some corrections are first proposed to the presented binary multiplier, while the discussion is later extended to some issues that have been found regarding the binary-to-BCD converter. [ABSTRACT FROM AUTHOR]

Advances in next-generation sequencing (NGS) allow for rapid development of genomics resources needed to generate molecular diagnostics assays for infectious agents. NGS approaches are particularly helpful for organisms that cannot be cultured, such as the downy mildew pathogens, a group of biotrophic obligate oomycetes that infect crops of economic importance. Unlike most downy mildew pathogens that are highly host-specific, Pseudoperonospora cubensis causes disease on a broad range of crops belonging to the family Cucurbitaceae. In this study, we identified candidate diagnostic markers for P. cubensis by comparing NGS data from a diverse panel of P. cubensis and P. humuli isolates, two very closely related oomycete species. P. cubensis isolates fo ra diverse hosts and geographical regions in the United States were selected for sequencing to ensure that candidates were conserved in P cubensis isolates infecting different cucurbit hosts. Genomic regions unique to and conserved in P. cubensis isolates were identified through bioinformatics. These candidate regions were then validated using PCR against a larger collection of isolates from P cubensis, P. humuli, and other oomycetes. Overall seven diagnostic markers were found to be specific to P. cubensis. These markers could be used for pathogen diagnostics on infected tissue, or adapted for monitoring airborne inoculum with real-time PCR and spore traps. [ABSTRACT FROM AUTHOR]

This study presents the results of the accumulation of 210 Po and 210 Pb in fish tissues and organs in a brackish-water marshland that is characterized by high concentrations of 222 Rn and 226 Ra supplied by submarine groundwater discharge (SGD). Tissues and organs from Cyprinus carpio , Chelon labrosus and Carassius auratus in the wetland were significantly enriched by both 210 Pb and 210 Po (up to 55 and 66 times, respectively) compared to blanks. The major input route of 210 Pb and 210 Po into the fish body seems to be through ingestion, due to the high levels of 210 Pb and 210 Po found in the gut content as well as in organs involved in digestion and metabolism (i.e. gut, kidney and hepatopancreas). Results showed that 210 Po was more accumulated in all fish tissues and organs except for the spine, which showed a higher affinity for 210 Pb, due to its capacity to replace Ca from apatite in bones. Over all the variables analyzed, fish tissues/organs and, secondarily, fish species were the most important factors explaining the concentration of radionuclides, whereas fish length and the sampling location played a minor role. The relationship of the two radionuclides varied markedly among tissues and their concentration levels were only correlated in gills, gut and, marginally, in spines. In general, the highest values of 210 Pb and 210 Po concentrations in tissues were found on C. labrosus tissues rather C. auratus and C. carpio . This study demonstrates that inputs of natural radionuclides supplied by SGD to coastal semi-enclosed areas (such as marshlands, lagoons or ponds) may significantly increase the contents of 210 Pb and 210 Po in fish tissues/organs. Thus, this study represents one of the first evidences of direct ecological effects derived from SGD. [ABSTRACT FROM AUTHOR]

Hepatitis B immunoprophylaxis failure is linked to high maternal viraemia. There is limited North American data on hepatitis B outcomes in pregnancy. Pregnant hepatitis B carriers were enrolled January 2011-December 2014 and offered tenofovir in the 3rd trimester if hepatitis B virus ( HBV)- DNA was >7-log IU/mL. Outcomes were determined in treated vs untreated patients. In total, 161 women with 169 pregnancies (one twin, 170 infants; median age 32 years), 18% (29/161) HBeAg+ and median HBV- DNA 2.51 log IU/mL ( IQR 1.66-3.65; range 0.8-8.1) were studied. 14.3% (23/161) received tenofovir due to high viral load (16/23, median 74 days, IQR 59-110) or due to liver disease (7/23). In 10/16 treated due to high viraemia, with confirmed adherence, follow-up HBV- DNA showed a 5.49 log decline ( P = 0.003). In treatment naïve mothers, median alanine aminotransferase ( ALT) increased from 17 IU/L ( IQR 12-24) to 29 ( IQR 18-36) post-partum ( P = 1.5e-7). In seven highly viraemic mothers who declined therapy ( HBV- DNA >8-log IU/mL); median ALT increased ~3X from baseline ( P < 0.01). 26% (44/169) had Caesarean section with no difference in treated vs untreated subjects. No tenofovir-treated mothers had renal dysfunction. Data were available on 167/170 infants; in 50.8% (85/167) who completed immunoprophylaxis, 98.8% (84/85, including 12 exposed to tenofovir in utero) were HBV immune. One infant born to an HBeAg+ mother with HBV- DNA >8-log IU/mL failed immunoprophylaxis. In this prospective Canadian cohort study, most untreated mothers experienced mild HBV flares. Tenofovir in pregnancy is well tolerated and reduces viral load prior to parturition. [ABSTRACT FROM AUTHOR]

The numerical simulation of complex flows has been a subject of intense research in the last years with important industrial applications in many fields. In this paper we present a finite element method to solve the two immiscible fluid flow problems using the level set method. When the interface between both fluids cuts an element, the discontinuity in the material properties leads to discontinuities in the gradients of the unknowns which cannot be captured using a standard finite element interpolation. The method presented in this work features a local enrichment for the pressure unknowns which allows one to capture pressure gradient discontinuities in fluids presenting different density values. The method is tested on two problems: the first example consists of a sloshing case that involves the interaction of a Giesekus and a Newtonian fluid. This example shows that the enriched pressure functions permit the exact resolution of the hydrostatic rest state. The second example is the classical jet buckling problem used to validate our method. To permit the use of equal interpolation between the variables, we use a variational multiscale formulation proposed recently by Castillo and Codina (2014) [21], that has shown very good stability properties, permitting also the resolution of the jet buckling flow problem in the the range of Weissenberg number 0 < We < 100, using the Oldroyd-B model without any sign of numerical instability. Additional features of the work are the inclusion of a discontinuity capturing technique for the constitutive equation and some comparisons between a monolithic resolution and a fractional step approach to solve the viscoelastic fluid flow problem from the point of view of computational requirements. [ABSTRACT FROM AUTHOR]

In this paper, three different fractional step methods are designed for the three-field viscoelastic flow problem, whose variables are velocity, pressure and elastic stress. The starting point of our methods is the same as for classical pressure segregation algorithms used in the Newtonian incompressible Navier–Stokes problem. These methods can be understood as an inexact LU block factorization of the original system matrix of the fully discrete problem and are designed at the pure algebraic level. The final schemes allow one to solve the problem in a fully decoupled form, where each equation (for velocity, pressure and elastic stress) is solved separately. The first order scheme is obtained from a straightforward segregation of pressure and elastic stress in the momentum equation, whereas the key point for the second order scheme is a first order extrapolation of these variables. The third order fractional step method relies on Yosida's scheme. Referring to the spatial discretization, either the Galerkin method or a stabilized finite element formulation can be used. We describe the fractional step methods first assuming the former, and then we explain the modifications introduced by the stabilized formulation we employ and that has been proposed in a previous work. This discretization in space shows very good stability, permitting in particular the use of equal interpolation for all variables. [ABSTRACT FROM AUTHOR]

The adsorption of Fe atom on graphene is studied by first-principles Density Functional Theory. The structural, electronic, and magnetic properties are analyzed at different coverages, all preserving C 6 v symmetry for the Fe adatom. We observed that binding energies, magnetic moments, and adsorption distances rapidly converge as the size of the supercell increases. Among the considered supercells, those constituted by 3 n graphene unit cells show a very peculiar behavior: the adsorption of a Fe atom induces the opening of a spin-dependent gap in the band structure. In particular, the gap amounts to tenths of eV in the majority spin component, while in the minority one it has a width of about 1 eV for the 3 × 3 supercell and remains significant even at very low coverages (0.25 eV for θ ≃ 2%). The charge redistribution upon Fe adsorption has also been analyzed according to state of the art formalisms indicating an appreciable charge transfer from Fe to the graphene layer. [ABSTRACT FROM AUTHOR]

• Fatigue models are classified in three classes according with their possible design application. • A new generalized parameter (GRV) is proposed to replace the stress range as driving force. • The probabilistic Castillo-Canteli fatigue model is revisited and improved to include the LCF regime. • The new probabilistic GRV -N field is applied to evaluate experimental results and discussed. In this work, three classes of fatigue models are reviewed according to the fatigue regimes commonly considered in the current components design. Particular attention is devoted to the so-called Class III fatigue models, covering the three fatigue regimes, namely, LCF, HCF and VHCF. The applicability and limitations of the proposed analytical sigmoidal solutions are discussed from the viewpoint of practical design. The compatible Weibull S-N model by Castillo and Canteli is revisited and improved by considering a new reference parameter GP = E· σ M · (dε/dσ)| M as the driving force alternative to the conventional stress range. In this way, the requirement, σ M ≤ σ u , according to the real experimental conditions, is fulfilled and the parametric limit number of cycles, N 0 , recovers its meaning. The probabilistic definition of the model on the HCF and VHCF regimes is maintained and extended to the LCF regime. The strain gradients may be calculated from the monotonic or cyclic stress–strain curve of the material although a direct derivation from the hysteresis loop is recommended. Some Class III fatigue models from the literature and another one improved by the authors are applied to the assessment of one experimental campaign under different stress ratios conditions and the results compared accordingly. Finally, the new probabilistic GP-N field is evaluated. The results confirm the practical confluence of the stress- and the strain-based approaches into a single and advantageous unified methodology. [ABSTRACT FROM AUTHOR]

Introduction: We compare demographic, socioeconomic, and anthropometric characteristics and blood pressure (BP), between rural and urban Peruvian indigenous women. These are preliminary results from a project on urbanization, migration, and health. Methods: Data were collected cross‐sectionally (2019) and compared between a rural (n = 92) and an urban (n = 93) community. Results: Height: μ = 148.3 ± 5.0 cm (range = 137–162), weight: μ = 62.0 ± 11.5 (range = 37.5–108.7), median waist circumference = 89.0 (IQR = 15.8, range = 64.0–126.0), BMI = 28.3 (IQR = 6.2, range = 16.7–40.0), with no significant rural–urban differences. Systolic but not diastolic BP was significantly higher in urban versus rural women (median = 110, IQR = 18, range = 80–170 vs. median = 120, IQR = 10, range = 90–170, p =.002 and median = 70, IQR = 17, range = 50–100 vs. median = 70, IQR = 10, range = 60–100, p =.354), respectively. Conclusions: Despite major lifestyle differences, there were no anthropometric differences between rural and urban women. Higher systolic BP in urban women may reflect social/economic stressors rather than dietary factors. [ABSTRACT FROM AUTHOR]

The epidemiology of infections in the puerperium (post partum period) is not well understood and remains underestimated because surveillance systems are often limited to the acute care setting. The most common source of persistent fever after delivery is genital tract infection for which diagnosis remains mostly clinical and antibiotic treatment empiric. This review will emphasize surgical site infections (SSIs) and endometritis. Septic thrombo-phlebitis, mastitis, urinary tract infections and rare infections will be covered in less detail. Puerperal sepsis will not be reviewed. [ABSTRACT FROM AUTHOR]

Highlights: [•] A method based on the use of AFM was proposed to measure CTE of thin films. [•] The effect the presence of TiO2 nanoparticles on the CTE of EVA was evaluated. [•] New theoretical model proposed to understand the influence of the filler on the CTE of composites. [•] Interphase and size of particles in composites are the main factors to change polymer matrix CTE. [Copyright &y& Elsevier]

We present a new environment for computations in particle physics phenomenology employing recent developments in cloud computing. On this environment users can create and manage 'virtual' machines on which the phenomenology codes/tools can be deployed easily in an automated way. We analyze the performance of this environment based on 'virtual' machines versus the utilization of physical hardware. In this way we provide a qualitative result for the influence of the host operating system on the performance of a representative set of applications for phenomenology calculations. [ABSTRACT FROM AUTHOR]

The productive performance of 24 crossbred dairy males (5/8 Holstein x 3/8 Zebu), of 330 ± 31 d of age and liveweight (LW) from 134.02 to 228.28 kg was assessed. The animals grazed on an association of glycine (Neonotonia wightii) and natural pasture during the rainy season (160 d). The system of 6 ha was divided into eight paddocks. The occupation and resting times were of 5 and 35 d, respectively, with stocking rate of four animals/ha. An amount of 1.50 kg of activator supplement of the ruminal fermentation (15.20 % of CP and 9.33 MJ kg of DM-1 of ME was offered. A grazing pressure of 12.90 kg DM per each 100 kg of LW was maintained. The daily mean gain (DMG) was of 589.13 g of LW per animal. The system favored the fulfillment of the ingestion capacity and the CP requirements, while the ME was slightly below the requirements (1.25 MJ) for the real DMG obtained. Besides, it allowed the inclusion of a great number of animals to the fattening. These results corroborate the necessity of working with lower animal stocking rate or with supplements with higher energy content to improve the use of the pastures CP, obtain higher DMG of LW and reduce the incorporation age of the animals to the fattening. [ABSTRACT FROM AUTHOR]

This paper illustrates the application of the discrete wavelet transform (DWT) for wandering and noise suppression in electrocardiographic (ECG) signals. A novel one-step implementation is presented, which allows improving the overall denoising process. In addition an exhaustive study is carried out, defining threshold limits and thresholding rules for optimal wavelet denoising using this presented technique. The systemhas been tested using syntheticECGsignals, which allowaccuratelymeasuring the effect of the proposed processing. Moreover, results from real abdominal ECG signals acquired from pregnant women are presented in order to validate the presented approach. [ABSTRACT FROM AUTHOR]

Abstract: To achieve a sustainable management of resources, political and economic decision-makers need indicators to quantify their technical choice in relation with resource consumption. In this study, a new indicator that reflects the power demand next to energy demand of systems such as buildings is developed. The relevance of the proposed power indicator is tested through two different kinds of systems: retaining walls for civil and agricultural engineering and residential houses. It enables to highlight a close relation between this indicator and the high power energy sources that may exist at different steps of a building's life cycle. This dependence is presented as a better indicator of sustainability than a traditional energy account as it reflects the ability for the system to rely on flow energies rather than on stock energies. [Copyright &y& Elsevier]

Epidemiological studies correlate low levels of vitamin D with the osteoarthritis (OA) progression. Cytokines and metalloproteases play a major role in OA promoting the inflammation and degradation of the cartilage and can be induced through the Toll-like receptor (TLR) pathway. The aim of this study was to evaluate the protective effect of vitamin D supplementation on the development of osteoarthritis (OA) through examining the genetic regulation of TLRs, cytokines, andmetalloproteases in chondrocytes as well as the wideness of cartilage in rats with OA. Our results demonstrate that the signaling through TLR-4 is a proinflammatory mechanism in osteoarthritis that drives the upregulation of MMP-3, IL-1β, and TNF-α gene expression, leading to cartilage degradation and inflammation. Vitamin D supplementation had a protective effect during the onset but not during the chronic stage of OA in the rat model. [ABSTRACT FROM AUTHOR]

Lysozyme is an enzyme with antibacterial activity often used as food preservative and as active ingredient in pharmaceutical preparations. Lysozyme is quantitatively important in human milk and has been proposed to be used in special products to improve infant health. The production of recombinant human lysozyme (rhLz) in rice is very valuable for its application in food and pharmaceutical industry. In this work, the effect of heat treatment and high pressure (HP) on the enzymatic activity of rhLz and on its antibacterial activity against Listeria monocytogenes was studied. No loss of rhLz enzymatic activity was found after Low Temperature Long Time (63°C for 30 min) and High Temperature Short Time (75°C for 15 s) pasteurization treatments. Likewise, HP-treatment at 600 MPa for 15 min at 20°C of rhLz in milk, whey or phosphate buffered saline (PBS) did not cause a decrease in its enzymatic activity. HTST treatment did not affect the antibacterial activity of rhLz with respect to the non-treated rhLz. However, LTLT treatment and treatments at 72°C for 10 min and 85°C for 15 s enhanced the antibacterial activity of rhLz, causing a reduction of bacterial CFU of about 4 log cycles, compared with the reduction of 2 cycles caused by non-treated rhLz. However, the antibacterial activity of rhLz treated at 85°C for 10 min was lower than that of non-treated protein. No reduction in the number of bacteria was observed when incubating them with non-treated or HP-treated rhLz in milk or whey, whereas a reduction of 2 log cycles was found for HP-treated rhLz in PBS, similar to that obtained for the non-treated sample. [ABSTRACT FROM AUTHOR]

This paper deals with the error recovery problem when scanned license plate data are used to predict traffic flows. The aim is to reduce the effects of errors owing to lost plates or mistaken transcription, to improve estimation results. To this end, a method is given and discussed for traffic flow prediction using plate scanning data and taking into account possible errors in plate number recognition. The proposed method uses Bayesian networks because this is an efficient tool for introducing the plate scan error flow as a variable in the model and mending the mistakes in the scan pattern. Several examples are used to illustrate the proposed model. Finally, some conclusions are included. [ABSTRACT FROM AUTHOR]

A statistical model for deriving the stress-life from the strain-life curves is presented. In this way, the fatigue characteristics are obtained not only for the high- but also for the low-cycle fatigue domains. The model reproduces the experimentally observed incurvation in the low-cycle fatigue region. The proposed method is finally illustrated by its application to a real data case. [ABSTRACT FROM AUTHOR]

Se evaluó el comportamiento productivo de 24 machos bovinos mestizos lecheros 5/8 Holstein x 3/8 Cebú, que se encontraban en pastoreo durante la época poco lluviosa, incluidos en la categoría de preceba. Pastaron en días alternos en seis hectáreas de asociación de glycine (Neonotonia wightii) y gramíneas. Tuvieron acceso a dos hectáreas de banco de biomasa de Pennisetum purpureum vc. Cuba CT-115. Consumieron 1.5 kg de suplemento activador de la fermentación ruminal por animal por día, con 15.20 % de PB y 9.33 MJ de EM. La carga total fue de tres animales por hectárea. Los tiempos de ocupación y reposo fueron de 8 y 56 d, respectivamente. Se utilizó el autopastoreo, el área no se fertilizó ni se regó. Se obtuvieron 491 g de GMD (ganancia media diaria) de PV en los 228 d que duró la categoría y una entrega de 789 kg totales de PV. ha-1 . La calidad nutritiva del CT-115 limitó el cumplimiento de los requerimientos nutricionales. Con este genotipo es necesario reducir la carga animal o mejorar la suplementación, si se desea reducir la duración de la categoría o aumentar la GMD para acceder a mercados más lucrativos. [ABSTRACT FROM AUTHOR]

The productive performance was evaluated in 24 crossbred 5/8 Holstein x 3/8 Zebu dairy bulls. They were under grazing conditions during the dry season and they were included in the pre-fattening category. They grazed in alternative days in six hectares with mixtures of glycine (Neonotonia wightii) and grasses. They had access to two hectares of biomass bank of Pennisetum purpureum cv. Cuba CT-115. They consumed 1.5 kg of supplement that activates the rumen fermentation per animal per day, with 15.20 % of CP and 9.33 MJ of ME. The total stocking rate was of three animals per hectare. The occupation and resting times were of 8 and 56 d, respectively. The auto-grazing was used. The grazing area was not fertilized or irrigated. Four hundred and ninety-one grams of ADG (average daily gain) of LW were obtained in the 228 d of this category and there was a total of 789 kg of LW.ha-1. The nutritive quality of the CT-115 limited the fulfillment of the nutritional allowances. With this genotype, it is necessary to reduce the stocking rate or improve the supplementation, if the duration of the category is intended to be reduced or the ADG is intended to be increased to get access to more lucrative markets. [ABSTRACT FROM AUTHOR]

Abstract: The SMILE project main aim is to build an efficient low-cost cluster based on FPGA boards in order to take advantage of its reconfigurable capabilities. This paper shows the cluster architecture, describing: the SMILE nodes, the high-speed communication network for the nodes and the software environment. Simulating complex applications can be very hard, therefore a SystemC model of the whole system has been designed to simplify this task and provide error-free downloading and execution of the applications in the cluster. The hardware–software co-design process involved in the architecture and SystemC design is presented as well. The SMILE cluster functionality is tested executing a real complex Content-Based Information Retrieval (CBIR) parallel application and the performance of the cluster is compared (time, power and cost) with a traditional cluster approach. [Copyright &y& Elsevier]

Abstract: This paper deals with the problem of building crack growth models and connecting them with Wöhler field models. After, analyzing the physical validity of some crack growth models, a general methodology to build models is presented starting by identifying the set of variables involved in the crack growth problem. Next, a minimum subset of dimensionless parameters using the Buckingham theorem is selected. The next step consists of imposing some consistency and compatibility conditions in terms of functional equations, which, once solved, provide the subset of crack growth models satisfying the required deterministic and stochastic compatibility conditions, which, in addition to providing mean values of the crack sizes as a function of time, as alternative models do, also give densities of the crack sizes. As a result, the main elements required to build a crack growth model, such as the initial crack size distribution, the crack growth function and a loading effect functions, have been identified. Finally, the compatibility of Wöhler field and crack growth models is dealt with and the advantages of such a dual treatment is emphasized. The methodology is illustrated with some examples, including crack growth for different load histories, and some conclusions are given. [Copyright &y& Elsevier]

Several variables were measured in pastures composed of associations of native grasses/legumes (Paspalum, Axonopus, Cynodon, Setaria, Desmodium and Calopogonium) and introduced species {Cynodon nlemfuensis, Brachiaria arrec-ta, Arachis pintoi). Pastures were placed under intensive rotational grazing (1-3 days of use; 36-60 days of recovery) by Holstein-Cebú cattle, during 3 13 days. 34 to 38 paddocks were sampled (1.1 ±0.2 ha/division) per season (northern-wind-NS, dry-DS and rainy-RS). Effects of season and month within season were tested. Botanical composition (%) was similar among seasons showing values of 49.3±0.02, 26.1 ±0.03, 12.5±0.04, 3.8±0.02, 6.0±0.02 and 2.3 ±0.01 for native grasses, Cynodon nlemfuensis, Brachiaria arrecta, legumes, and broad and narrow leafed weeds, respectively. The standing dry matter before grazing (SDMBG, kg/ha) was similar among seasons (2040 ±38); while the standing dry matter after grazing (SDM AG, kg/ ha) was similar between NS (1324±61) and DS (1468 ±78), both were lower than RS (1668 ± 66). The leaves had a higher content of crude protein than the stems in NS (1 1.7±0.5% vs. 5.7±0.5%) and RS (13.0±0.3% vs. 7.8±0.4%). Both, season and month within season did not affect dry matter availability (9.57±0.21 kg DM/100 kg LW). Apparent dry matter intake (kg DM/100 kg LW) in NS (2.42±0.19) was higher than that in DS (1.77±0.24), but similar to RS (1.96±0.20). The use (%) of the SDMBG in NS (33.1 ±0.1%) was higher than that in DS (23.4±0.1%)andRS(19.6±0.1%),withno difference between the last two. Season did not affect pasture growth rate (13.7± 1.9 kg DM/ ha/day). Results suggest that an intensive use of native grass-based pastures is possible without the detriment of their vegetation cover. [ABSTRACT FROM AUTHOR]

Sensitivity analysis in regression is concerned with assessing the sensitivity of the results of a regression model (e.g., the objective function, the regression parameters, and the fitted values) to changes in the data. Sensitivity analysis in least squares linear regression has seen a great surge of research activities over the last three decades. By contrast, sensitivity analysis in non-linear regression has received very little attention. This paper deals with the problem of local sensitivity analysis in non-linear regression. Closed-form general formulas are provided for the sensitivities of three standard methods for the estimation of the parameters of a non-linear regression model based on a set of data. These methods are the least squares, the minimax, and the least absolute value methods. The effectiveness of the proposed measures is illustrated by application to several non-linear models including the ultrasonic data and the onion yield data. The proposed sensitivity measures are shown to deal effectively with the detection of influential observations in non-linear regression models. [ABSTRACT FROM AUTHOR]

The productive performance of twenty-four 5/8 Holstein x 3/8 Zebu crossbred bulls of 490 d of age was evaluated from 228.28 kg of liveweight (LW) until 412.24 kg of LW at slaughter. The animals grazed in 6 ha of a silvopastoral system at 100 % association of Leucaena leucocephala and grasses. In the dry season, in alternate days, they had access to 2 ha of biomass bank of Pennisetum purpureum cv. Cuba CT-115. Each area was divided into 8 paddocks. The auto-grazing was used without fertilization or irrigation. The occupation and resting times were of 7 and 49 d, respectively. The stocking rate was of 3 and 4 animals/ha in the silvopastoral system plus the biomass bank and in the silvopastoral system in the dry and rainy seasons, respectively. They consumed 1.50 kg/animal/d of rumen activating supplement. The daily average gain (DAG) of LW was of 519.35 and 609.76 g for the dry and rainy season, respectively. The system guaranteed the fulfillment of the protein requirements and permitted supplying 1.24 t/ha of LW at slaughter, with animals of 26.72 months of age. It was corroborated the need for working with smaller stocking rates and/or supplements with higher nutritive value to increase the DAG of LW and slaughter at early ages and get better market results. [ABSTRACT FROM AUTHOR]

Se evaluó el comportamiento productivo de 24 machos mestizos 5/8 Holstein x 3/8 Cebú, de 490 d de edad, desde los 228.28 kg de peso vivo (PV) hasta los 412.24 kg de PV al sacrificio. Los animales pastaron en 6 ha de un silvopastoreo 100 % asociado de Leucaena leucocephala y gramíneas. En la época poco lluviosa, en días alternos, tuvieron acceso a 2 ha de banco de biomasa de Pennisetum purpureum vc. Cuba CT-115. Cada área se dividió en 8 cuartones. Se empleó el autopastoreo, sin fertilización ni riego. Los tiempos de ocupacióny reposo fueron de 7 y 49 d, respectivamente. La carga fue de 3 y 4 animales/ha en el silvopastoreo más el banco de biomasa y en el silvopastoreo, en las épocas poco lluviosa y lluviosa, respectivamente. Consumieron 1.50 kg/animal/d de suplemento activador del rumen. La ganancia media diaria (GMD) de PV fue de 519.35 y 609.76 g durante las épocas poco lluviosa y lluviosa, respectivamente. El sistema garantizó el cumplimiento de los requerimientos proteicos y permitió suministrar 1.24 t/ha de PV al sacrificio, con animales de 26.72 meses de edad. Se corroboró la necesidad de trabajar con cargas menores y/o suplementos con mayor valor nutritivo que permitan aumentar la GMD de PV, para lograr el sacrificio a edades tempranas y obtener mejores resultados en el mercado. [ABSTRACT FROM AUTHOR]

Goal: Terminal renal failure affects all the person's life dimensions. The impact of this illness during adolescence is quite dramatic because the adolescent must live with the illness demands and the demands from this crucial developmental stage. Knowledge regarding the impact of the dialysis catheter on the adolescent's life is spare. Methodology: A phenomenological study was carried out with 8 female and male adolescents that were in dialysis. Findings: The adolescents had to learn to live with the dialysis catheter in their body. The catheter became an obstacle to achieve their identity and deteriorated their physical appearance and peer relationships. [ABSTRACT FROM AUTHOR]

In this article, the performance of a stabilized VMS-type finite element formulation of a non-residual structure is numerically verified for highly convective natural flows. The novelty of the method is the time-dependent nature of the sub-scales and the introduction of two components for the sub-scale velocities, which allows the resolution of chaotic and highly convective problems without the need to include an additional turbulence model and its using equal order interpolation between velocity and pressure. The natural heat convection problems of the square and cubic cavities are solved up to a Rayleigh number of 1 0 10 and 3. 3 × 1 0 7 , respectively. Additionally, the stability of the problem is investigated by conducting an analysis of its Hopf bifurcation. As a distinctive feature, the work includes the assessment of the influence of incorporating dynamic sub-scales, with an emphasis on the accuracy of the numerical solutions obtained, that includes a comparison with the results predicted by the quasi-static formulation of the same method. The comparisons between both formulations were made using direct and iterative solvers. The results reported in this article allow verifying the performance, precision, and robustness of the dynamic formulation used to solve highly nonlinear problems with strong thermal coupling. • A non-residual based VMS formulation is proposed to solve thermally coupled flows. • The method is capable of solving chaotic flows without the need of a turbulent model. • The benefits of including time-dependent sub-scales are evaluated numerically. • The stability of the problem from the Hopf bifurcation to chaotic flows is evaluated. • 2D and 3D problems are solved to check the accuracy and robustness of the method. [ABSTRACT FROM AUTHOR]

In this paper, the problem of selecting damage measures and ways of accumulating damage due to a fatigue load history is dealt with. First, a statistical model and a normalization procedure, that allow using a reference stress level or a reference random variable for analysing the fatigue data coming from tests at different stress ranges, are presented. Next, some desirable properties for a damage measure are discussed and several alternative damage measures are investigated based on these properties. It is shown how several damage measures, such as the Palmgren–Miner number, do not satisfy these properties. On the contrary, the standardized logarithm of the number of cycles, which coincides with the standardized Palmgren–Miner number, a Weibull reference variable and a probability based damage measure are demonstrated to satisfy these properties and to be good alternatives for a damage measure. It is shown that the most convenient damage measures are obtained by assuming that two pieces subjected to different stress level tests suffer the same damage if, at the end of the corresponding tests, they have the same probability of failure. The problem of extending the damage measure below the zero-percentile area (where fatigue failure does not occur) is also analysed. Finally, the damage accumulation problem for non-constant stress range load histories is discussed, and formulae for calculating the associated damage are given. For the sake of illustration, several examples of different load types are also given. [ABSTRACT FROM AUTHOR]

Introduction: Terminal renal failure affects all aspects of the person's life. The impact of this illness during the adolescence is quite dramatic since the adolescent must overcome the demands from the developmental stage and the illness situation. Knowledge about the illness impact on the adolescents' life is scarce; as a contribution to increasing this knowledge, a study was done to describe the lived experiences of adolescents in dialysis.Methodology: The study is qualitative; the methodological strategy used was interpretive phenomenolgy based on Heidegger's phylosophy.Findings: Adolescents in dialysis experienced losses in their everyday life, especially as students; they also experienced loss of their independence, their previous body image and their desirable body image. The imposed and rigid timetables for the pharmacological treatment and dialysis procedure, the dialysis catheter and the diet restrictions are the main causes of their losses. Peer relationships deteriorated due to the social isolation the adolescents imposed on themselves as a way to cope with the losses. Renal transplant is perceived as a mean to recover all they have lost.Conclusion: Knowledge generated by this study would contribute to provide health care more congruent with the adolescents' everyday needs. [ABSTRACT FROM AUTHOR]

This paper describes the feasibility of an aerobic system (rotating biological contactor, RBC) and a biological anaerobic system (upward-flow anaerobic sludge bed reactor) at small scale for the treatment of a landfill leachate. In the first phase of the aerobic system study, a cyclic-batch RBC system was used to select perforated acetate discs among three different acetate disc configurations. These discs were chosen on the basis of high COD removal (65%) and biological stability. In the second phase, the RBC system (using four stages) was operated continuously at different hydraulic retention times (HRT), at different rotational speeds, and with varying organic concentrations of the influent leachate (2500–9000mgL−1). Forty percent of the total surface area of each perforated disc was submerged in the leachate. A COD removal of about 52% was obtained at an HRT of 24h and a rotational speed of 6rpm. For the anaerobic system, the reactor was evaluated with a volumetric organic load of 3273g-COD m−3 day−1 at an HRT of 54, 44, 39, 24 and 17h. At these conditions, the system reached COD removal efficiencies of 62%, 61%, 59%, 44% and 24%, respectively. [Copyright &y& Elsevier]

The goal of this paper is two fold. First, it introduces a general parametric lifetime model for high-cycle fatigue regime derived from physical, statistical, engineering and dimensional analysis considerations. The proposed model has two threshold parameters and three Weibull distribution parameters. A two-step procedure is presented to estimate the parameters. In the first step, the two threshold parameters are estimated by minimizing a least squares regression function. In the second step, the parameters are estimated by the maximum likelihood method after pooling together the data from different stress levels. Since parameter estimation should always be accompanied by a sensitivity analysis of the fitted model, the second goal of this paper is to propose a method for sensitivity analysis for fatigue models. We show that the proposed sensitivity analysis methods are general and can be applied to any fatigue or lifetime model, not just to the one proposed here. Although several fatigue models have been proposed in the literature, to our knowledge this is the first attempt to produce methods for sensitivity analysis for fatigue models. The proposed method makes use of the well-known duality property of mathematical programming, which states that the partial derivatives of the primal objective function with respect to the constraints right hand side parameters are the optimal values of the negative of the dual problem variables. For the parameters or data, for which sensitivities are sought, to appear on the right hand side, they are converted into artificial variables and set to their actual values, thus obtaining the desired constraints. Both the estimation and sensitivity analysis methods are illustrated by two examples, one application using real fatigue data and the other using simulated data. In addition, the sensitivity proposed method is also applied to an alternative fatigue model. Finally, some specific conclusions and recommendations are also given. [ABSTRACT FROM AUTHOR]

In this paper methods and algorithms for identifying the main elements (edges and facets of any dimension) of a cone and a polytope, and calculating the corresponding hypervolumes are presented. The cones and polytopes are supposed to be given as the non-negative linear combination and the convex hull generated by a, not necessarily minimal, set of vectors (points), respectively, and they can be degenerated (of a dimension smaller that that of the proper space in which they are contained). First a minimum set of generators (edges and vertices) are obtained by eliminating the redundant vectors. In the case of cones, the linear space basis and the minimal cone generators are obtained. Second the set of all facets of any dimension are identified. Finally, an algorithm for obtaining the associated hypervolumes of any dimension, i.e. the length of its edges, the areas of its faces of dimension two, and the hypervolumes of its facets of any dimension, is introduced. The proposed formula leads to a recursion that gives the hypervolumes of dimension n as a function of other hypervolumes of dimension n - 1. Examples are used to illustrate the proposed methods and algorithms. [ABSTRACT FROM AUTHOR]

Abstract: The hydrolytic activity of Candida antarctica lipase B (CAL-B) was studied using 15 amides with different linear saturated acyl residues and substituents in the aromatic amine. A strong dependence of the hydrolysis rate on the length of the acyl residue and the substituents groups in the aromatic ring of the amides was demonstrated, with the highest hydrolytic initial reaction rates found for the C10 acyl derivates and benzylamides. The C10 benzylamide, an amide without substituents in the aromatic ring was hydrolyzed almost as fast as capsaicin and five times faster that the corresponding C10 vanillyl derivative. Therefore, a benzylamide bearing the non-linear unsaturated acyl residue of capsaicin (8-methyl-6-nonanenoic acid) was synthesized. This substrate was hydrolyzed four times faster than capsaicin. Although it has been widely claimed that lipases rarely display amidase activity, with this contribution we demonstrate that the amidase activity of CAL-B is dependent on the structural features of the substrate. [Copyright &y& Elsevier]

Industrial statisticians frequently face problems in their practice where adjustment of a manufacturing process is necessary. In this paper, a view of the origins and recent work in the area of statistical process adjustment (SPA) is provided. A discussion of some topics open for further research is also given including new problems in semiconductor manufacturing process control. The goal of the paper is to help display the SPA field as a research area with its own identity and content, and promote further interest in its development and application in the industry. [ABSTRACT FROM AUTHOR]

This paper shows how the mathematical and the engineering points of view are complementary and help to model real problems that can be stated as systems of linear equations and inequalities. The paper is devoted to point out these relations and making them explicit for the readers to realize about the new possibilities that arise when contemplating the compatibility conditions or the set of general solutions from the dual perspective. After reviewing an orthogonally based powerful algorithm to analyse the compatibility of linear systems of equations and solving them, a water supply problem is used to illustrate its mathematical and engineering multiple aspects, including the optimal statement of the problem in terms of an adequate selection and numbering of equations and unknowns, an analysis of the compatibility conditions and a physical interpretation of the general solution, together with that of each individual generators of the affine space. The possibilities of removing unknowns without altering the compatibility of the problem is also analysed. Next, the Γ-algorithm to analyse the compatibility of linear systems of inequalities and solving them is described and then, the water supply problem is revisited adding some constraints, such as capacity limits for the pipes and retention valves, and discussed as to how they affect the resulting general solution and other aspects. Finally, some conclusions are derived. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]