A Hierarchical Bayesian Model for Frame Representation

In many signal processing problems, it may be fruitful to represent the signal under study in a frame. If a probabilistic approach is adopted, it becomes then necessary to estimate the hyper-parameters characterizing the probability distribution of the frame coefficients. This problem is difficult since in general the frame synthesis operator is not bijective. Consequently, the frame coefficients are not directly observable. This paper introduces a hierarchical Bayesian model for frame representation. The posterior distribution of the frame coefficients and model hyper-parameters is derived. Hybrid Markov Chain Monte Carlo algorithms are subsequently proposed to sample from this posterior distribution. The generated samples are then exploited to estimate the hyper-parameters and the frame coefficients of the target signal. Validation experiments show that the proposed algorithms provide an accurate estimation of the frame coefficients and hyper-parameters. Application to practical problems of image denoising show the impact of the resulting Bayesian estimation on the recovered signal quality

Van der Waals interactions at surfaces by DFT using Wannier functions

The method recently developed to include Van der Waals interactions in the Density Functional Theory by using the Maximally-Localized Wannier functions, is improved and extended to the case of atoms and fragments weakly bonded (physisorbed) to metal and semimetal surfaces, thus opening the way to realistic simulations of surface-physics processes, where Van der Waals interactions play a key role. Successful applications to the case of Ar on graphite and on the Al(100) surface, and of the H2 molecule on Al(100) are presented.Comment: submitted to Phys. Rev. Let

Effect of nitrogen level application on yield and fruit quality of Navel orange variety in a sandy soil

L’objectif de cet essai est d'évaluer l'effet de la dose d'azote sur le rendement et la qualité des fruits et de déterminer la dose optimale en azote pour les arbres de l’orange Navel greffé sur le porte-greffe citrange Troyer planté en 1964 en plein champ à un espacement de 7mx7m (204 arbres/ha) au niveau de la station expérimentale d’El Menzeh, INRA Maroc. Le dispositif adopté est un bloc aléatoire complet avec trois blocs rangés en 4 arbres consécutifs par bloc sur la même ligne. Quatre doses de N ont été testés : (T0 (Témoin) : 0, T1 : 100, T2 : 200, T3 : 300 Kg N/ha). Les paramètres mesurés sont : le calibre des fruits, le poids moyen par fruit, la qualité des fruits (le rendement en jus, l’acidité du jus, l’extrait sec soluble (ESS ou °Brix) et l’indice de maturité (E/A)) et le rendement en fruits. Le rendement en fruits, le poids moyen des fruits, le calibre des fruits, l’extrait sec soluble (TSS), l'acidité du jus et l'indice de maturité de l’orange Navel ont répondu significativement à l’augmentation de la dose d’azote. Le rendement en kg de fruits/arbre a été considérablement amélioré avec l'augmentation de la dose d'azote. Par ailleurs, les rendements les plus élevés (129.21 et 139.82 kg/arbre) ont été enregistrés sous les traitements T2 et T3 respectivement. Par contre, le rendement en fruits/arbre le plus faible a été obtenu chez les arbres non fertilisés (témoin). Le poids des fruits (268.54 et 276.50g) et la taille des fruits (78.94 et 80.87 mm) les plus élevés ont été enregistrés avec les même traitements T2 et T3 respectivement. La teneur totale en sucre soluble (TSS) la plus élevée a été enregistrée chez les arbres des traitements T2 et T3 (12.20 et 11.70 °Brix respectivement). Par ailleurs, une augmentation significative de l'acidité du jus de fruits de l’orange Navel a été également enregistrée en augmentant la dose d’azote. L'acidité la plus élevée a été obtenue par les mêmes traitements T2 et T3 (1,13 et 1.20 % respectivement). L’application de 200 Kg de N /ha a permis d’avoir un rendement maximal et une qualité optimale des fruits des oranges Navel greffés sur le porte-greffe citrange Troyer sur un sol sableux dans la région de Gharb.The objective of the present paper was to evaluate the effect of nitrogen level on yield and fruit quality of citrus and to determine the optimum N fertilizer rates of Navel orange variety budded on Troyer citrange rootstock in field conditions. The orange Navel orchard spaced 7mx7m (204 trees/ha) grown in 1964 on a sandy soil at the experimental station of El Menzeh, INRA Morocco. The experiment was set up in a complete randomized block design with three blocks and the experimental unit was composed on 4 consecutive trees in the row. Four fertilization treatments of N (Kg/ha) (T0 (control): 0, T1: 100, T2: 200, T3: 300) were applied to Navel citrus tree in field conditions over two seasons 2012-2013 and 2013-2014.Fruit yield, fruit weight, fruit size, total soluble sugar (TSS) content, acidity of juice and maturity index of Navel orange were significantly affected by increasing N level. Fruit yield/tree was improved significantly with increase in N rate. Significant highest yields (129.21 and 139.82. kg/tree) were recorded under treatments T2 and T3 respectively. The lowest fruit yield/tree was obtained from untreated control plot. Maximum fruit weight (268.54 and 276.50 g) and fruit size (78.94 and 80.87 mm) was recorded with the same treatments T2 and T3 respectively. Total soluble sugar content was also maximum in trees receiving treatment (T2) and treatment (T3) 12.20 and 11.70°Brix respectively. Significant increase in acidity of juice of fruit Navel orange was also recorded by increasing the rate of N. The highest acidity (1.13 and 1.20%) was achieved by the same treatments T2 and T3 respectively. Two-year studies showed that application of fertilizers at the rate of 200 Kg N/ha would be optimum for achieving higher yield and better fruit quality of Navel orange variety in sandy soil in Gharb area

Optimization of NPK levels of Clementine Sidi Aissa (Citrus reticulata Blanco) trees grafted on different citrus rootstocks

Received: August 15th, 2023 ; Accepted: October 18th, 2023 ; Published: November 5th, 2023 ; Correspondence: [email protected] present study aims to investigate the impact of various nitrogen concentrations on young Clementine Sidi Aissa citrus trees (Citrus reticulata Blanco), grafted on five citrus rootstocks namely Moroccan Carrizo citrange, French Carrizo citrange, Troyer citrange, Citrus macrophylla, and sour orange (Citrus aurantium L.). The experiment took place in greenhouses at the Experimental station of El Menzeh INRA-Morocco, with the young trees grown in containers. We applied five different nitrogen treatments (expressed as mg L-1 of N-P2O5-K2O): (0–0–0), (0–25–50), (25–25–50), (50–25–50), and (100–25–50). The split-plot experimental design was used with three replications. The findings demonstrate that the nitrogen enrichment resulted in enhanced plant growth, marked by increased plant height, rootstock and scion stem diameters, diameter and shoot length, relative water content (RWC), as well as leaf chlorophyll and proline content. Optimal growth of the Clementine Sidi Aissa trees was observed under the 100–25–50 (mg L-1 of N-P2O5-K2O) treatment. The study also found that leaf nitrogen concentration increased in line with the quantity of nitrogen added, whereas the percentages of phosphorous and potassium in the leaves decreased. The most significant growth increase across the majority of the studied parameters was noted in Clementine Sidi Aissa trees grafted on Moroccan Carrizo citrange and Troyer citrange rootstocks

Averaging level control to reduce off-spec material in a continuous pharmaceutical pilot plant

The judicious use of buffering capacity is important in the development of future continuous pharmaceutical manufacturing processes. The potential benefits are investigated of using optimal-averaging level control for tanks that have buffering capacity for a section of a continuous pharmaceutical pilot plant involving two crystallizers, a combined filtration and washing stage and a buffer tank. A closed-loop dynamic model is utilized to represent the experimental operation, with the relevant model parameters and initial conditions estimated from experimental data that contained a significant disturbance and a change in setpoint of a concentration control loop. The performance of conventional proportional-integral (PI) level controllers is compared with optimal-averaging level controllers. The aim is to reduce the production of off-spec material in a tubular reactor by minimizing the variations in the outlet flow rate of its upstream buffer tank. The results show a distinct difference in behavior, with the optimal-averaging level controllers strongly outperforming the PI controllers. In general, the results stress the importance of dynamic process modeling for the design of future continuous pharmaceutical processes

Fracture Process in ± θ Laminates Subjected to Mode II Loading

This work studies the behavior of a multidirectional laminate under Mode II loading. We describe the process of delamination in a reinforced composite of glass/epoxy. The stacking sequence (plies orientation [±θ]) was selected to minimize the coupling effects. The Mode II interlaminar test under three-point bending and cantilever flexure using ENF (End Notch Flexure) and ELS (End Load Split) specimens, respectively, was performed and analyzed. The test procedures and the results of strain-energy-release rate study for crack initiation are presented. The fracture process and the mechanical behavior of the two types of specimens are analyzed. The analysis clearly shows a close link between the angle θ, the ratio a/L, and the thickness h of the specimen. Fracture by delamination can be obtained only with an optimal choice of these parameters. The analysis of the states of stresses at the tip of crack allows us to explain the phenomenon of bifurcation between plies and is confirmed by the experimental results.Исследуется поведение многомерного ламината при его нагружении по типу KII . Описан процесс деламинирования упрочненного стеклоэпоксидного композита. Для минимизации эффектов трения выбрана ориентация ± θ. Рассмотрена методика межламинарных испытаний по типу KII с использованием схем трехточечного и консольного изгиба соответственно образцов типа ENF (торцевое защемление с консольным изгибом нагрузкой, равномерно распределенной по ширине свободного торца) и ELS (шарнирно закрепленная балка с центральной нагрузкой, равномерно распределенной по ширине балки). Представлены экспериментальные методики и результаты исследования скоростей высвобождения энергии деформации при инициировании трещин. Для двух вышеуказанных типов образцов проанализирован процесс разрушения и механического поведения материала. Установлена тесная корреляционная связь между величинами угла θ, соотношением a/L и толщиной образцов h. Показано, что разрушение вследствие деламинации возможно только при условии оптимального выбора этих параметров. Анализ напряженного состояния в вершине трещины позволяет объяснить явление межслойной бифуркации, его результаты хорошо согласуются с экспериментальными данными.Досліджується поведінка багатовимірного ламіната при його навантаженні за типом KII . Описано процес деламінування зміцненого склоепоксидного композита. Для мінімізації ефектів тертя вибрано орієнтацію ± θ. Розглянуто методику міжламінарних випробувань за типом KII із використанням схем триточкового і консольного згину відповідно зразків типу ENF (торцеве затиснення з консольним згином навантаженням, що рівномірно розподілене по ширині вільного торця) і ELS (шарнірно закріплена балка з центральним навантаженням, що рівномірно розподілене по ширині балкі). Представлено експериментальні методики і результати щодо швидкостей звільнення енергії деформації при ініціюванні тріщин. Для двох вищевказаних типів зразків проаналізовано процес руйнування і механічної проведінки матеріалу. Установлено кореляційний зв’язок між величинами кута θ, відношенням a /L і товщиною зразків h. Показано, що руйнування внаслідок деламінації можливе лише за умови оптимального вибору цих параметрів. Аналіз напруженого стану у вістрі тріщини дозволяє пояснити явище міжшарової біфуркації і добре узгоджується із експериментальними даними

Mathematical modeling and design of layer crystallization in a concentric annulus with and without recirculation

A solution layer crystallization process in a concentric annulus is presented that removes the need for filtration. A dynamic model for layer crystallization with and without a recirculation loop is developed in the form of coupled partial differential equations describing the effects of mass transfer, heat transfer, and crystallization kinetics. The model predicts the variation of the temperature, concentration, and dynamic crystal thickness along the pipe length, and the concentration and temperature along the pipe radius. The model predictions are shown to closely track experimental data that were not used in the model's construction, and also compared to an analytical solution that can be used for quickly obtaining rough estimates when there is no recirculation loop. The model can be used to optimize product yield and crystal layer thickness uniformity, with constraints on the supersaturation to avoid bulk nucleation by adjusting cooling temperatures in the core and jacket. © 2013 American Institute of Chemical Engineers

Mathematical modeling and design of layer crystallization in a concentric annulus with and without recirculation [Abstract]

Mathematical modeling and design of layer crystallization in a concentric annulus with and without recirculation [Abstract

Prostanoid EP₂ Receptors Are Up-Regulated in Human Pulmonary Arterial Hypertension: A Key Anti-Proliferative Target for Treprostinil in Smooth Muscle Cells

Prostacyclins are extensively used to treat pulmonary arterial hypertension (PAH), a life-threatening disease involving the progressive thickening of small pulmonary arteries. Although these agents are considered to act therapeutically via the prostanoid IP receptor, treprostinil is the only prostacyclin mimetic that potently binds to the prostanoid EP₂ receptor, the role of which is unknown in PAH. We hypothesised that EP₂ receptors contribute to the anti-proliferative effects of treprostinil in human pulmonary arterial smooth muscle cells (PASMCs), contrasting with selexipag, a non-prostanoid selective IP agonist. Human PASMCs from PAH patients were used to assess prostanoid receptor expression, cell proliferation, and cyclic adenosine monophosphate (cAMP) levels following the addition of agonists, antagonists or EP₂ receptor small interfering RNAs (siRNAs). Immunohistochemical staining was performed in lung sections from control and PAH patients. We demonstrate using selective IP (RO1138452) and EP₂ (PF-04418948) antagonists that the anti-proliferative actions of treprostinil depend largely on EP₂ receptors rather than IP receptors, unlike MRE-269 (selexipag-active metabolite). Likewise, EP₂ receptor knockdown selectively reduced the functional responses to treprostinil but not MRE-269. Furthermore, EP₂ receptor levels were enhanced in human PASMCs and in lung sections from PAH patients compared to controls. Thus, EP₂ receptors represent a novel therapeutic target for treprostinil, highlighting key pharmacological differences between prostacyclin mimetics used in PAH