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This paper is based mainly on Titchmarsh’s theorem (Introduction to the theory of Fourier integrals. Clarendon Press, Oxford, 1937, Theorem 84) in the one-dimensional case. Abilov et al. (Comput Math Math Phys 48:2146, 2008) proved two useful estimates for the Fourier transform in the space of square integral multivariable functions on certain classes of functions characterized by the generalized continuity modulus, and these estimates are proved by Abilovs for only two variables, using a translation operator. The purpose of this paper is to study these estimates for Quaternion Fourier transforms, also the functions satisfy Lipschitz conditions of certain orders. Thus we study the Quaternion Fourier transforms of Lipschitz function in the functions space Lr(R2,H), where Ha quaternion algebra which will be specified in due course.

The (right-sided) quaternion Fourier transform satisfies some uncertainty principles in a similar way to the Euclidean Fourier transform. Donoho–Stark’s uncertainty principle is obtained for the quaternion Fourier transform.

This work deals with some major aspects of ultrasonic traveling-wave piezoelectric motor modelling in the context of an automotive application. The aim here is to establish a proper model of this type of actuator, reflecting its behaviour. This work is a part of a larger study on the headlight automatic position control on vehicles conducted in the framework of the OpenLab “Electronics and Systems for Automotive” combining IMS laboratory and Stellantis company. The main complexity of this work is to create a proper simulator of this type of actuator, and discussing and simulating some of its behaviours, beyond what is commonly discussed in the literature, such as the direction inversion, and holding torque. Analyses are conducted on various inputs to prepare the control design.

Automotive headlights system represents a safety key system when it comes to drive by night. It aims to increase the comfort of the driver by providing a clear visibility in order to anticipate obstacles and follow the right path. One of the main challenges that the lighting system is facing today is its automatic leveling adjustment. Variations of load of the vehicle, its dynamics and the environment are the main sources of disturbance to the leveling system. These disturbances causes variations of vehicle pitch angle and as a result the lighting cut-off level that may glare other road users and affect the driver's visibility range. This paper proposes an innovative automatic leveling system based on an ultrasonic motor which is able to dynamically reject such disturbances on the lighting cut-off level using a robust CRONE controller.

We prove various mathematical aspects of the quantitative uncertainty principles, including Donoho–Stark’s uncertainty principle and a variant of Benedicks theorem for Lions transform.

The purpose of this study was to assess the feasibility of polymer inclusion membrane (PIM) to eliminate xenoestrogens (EDCs) bisphenol A (BPA) from synthetic wastewater as well as identify the major variables playing a significant role in the process. To achieve this goal, prepared PIM containing derivatives of calix[4]resorcinarene as the carrier, cellulose triacetate (CTA) as the base polymer, and 2-nitrophenyloctylether (2-NPOE) as a plasticizer has been used. The capability of PIM to remove contaminants was assessed using BPA as a model contaminant. The transport flux of BPA through the prepared PIMs was found to be dependent on various external factors such as; concentration of the carrier and the plasticizer in the membrane phase, pH of the aqueous feed phase, and thickness of the membrane. The corresponding stirring speed, pH of feed phase, the initial concentration of BPA in feed phase, carrier content, and plasticizer were: 600 rpm, pH 4, 100 mg dm–3, 400 mg g–1of support, and 3 mL g–1CTA, respectively. Up of 90% of BPA was transported from the feed phase to the stripping phase in 5 d, when the initial concentration of target was 100 mg L–1, and initial flux was found to be 5 × 10–7(mol m–2s–1). BPA can be transported through PIM when it is present in an undissociated state in aqueous solution. PIM stability after three cycles of transport processes was examined. The separation by using PIM has been identified as a promising technology for removing organic contaminants entering the water cycle.

Surgical training traditionally adheres to the apprenticeship paradigm, potentially exposing trainees to an increased risk of complications stemming from their limited experience. To mitigate this risk, augmented and virtual reality have been considered, though their effectiveness is difficult to assess.

The Weinstein transform satisfies some uncertainty principles in a similar way to the Euclidean Fourier transform. Donoho–Stark’s uncertainty principle is obtained for the Weinstein transform.

In mammals testicular and epididymal temperature increase impairs spermatogenesis. This experimental study investigates the effects of a mild testis temperature increase (i.e. testis temperature remains below core body temperature) on sperm aneuploidy in men. In 5 fertile volunteers a testicular temperature increase was induced by maintaining the testes at suprascrotal position using specially designed underwear for 15 ± 1 h daily for 120 consecutive days. After heating men were followed for next 180 days. A control group (27 men) was recruited. Semen samples were collected before, during and after heating period and analyzed for chromosomes X, Y and 18 for aneuploidy using FISH. A total of 234,038 spermatozoa were studied by FISH. At day 34 of heating, mean sperm aneuploidy values were not modified. From day 34 of heating until day 45 post heating, FISH evaluation was not possible due to the drastic fall of sperm count. At day 45 post-heating total sperm aneuploidy percentage was twice higher than before heating whereas. Sex disomy (sperm XY18), sex chromosome nullisomy (sperm 18) were significantly higher than controls. These effects were completely reversed at 180 days post heat exposure. Conclusion: A mild rise in testicular temperature significantly increases sperm aneuploidies, reflecting an effect on the meiosis stage of spermatogenesis. The effect of heating was reversible and suggests that recovery of aneuploidy to normal values requires at least two cycles of spermatogenesis. Nonetheless, the low number of volunteers was a limitation of this pilot study and warrants further research on larger population.

This research work focuses on the transport of citric acid from aqueous solutions using a polymer inclusion membrane (PIM). The PIM contains calix[4]resorcinarene as the carrier, mixture of cellulose triacetate and cellulose acetate (CA) as the base polymers, and 2-nitrophenyl octyl ether as a plasticizer. The transport percentage of citric acid was found to be dependent on various factors such as the concentration of the carrier and the plasticizer in the membrane phase, pH of the aqueous feed phase, and stirring speed. The corresponding stirring speed, pH of feed phase, the initial concentration of citric acid in feed phase, carrier content, and plasticizer were: 600 rpm, 2, 10–2 M, 0.15 g/g of support, and 0.03 mL, respectively. The 86% of citric acid was transported from feed phase to stripping phase in 5 d. This study shows that PIM composition has a great influence on citric acid recovery. It may be concluded that PIM with calix[4]resorcinarene (RC8) as the carrier can be successfully used for the extraction of citric acid from aqueous solutions.

Nowadays, there are increasingly stringent regulations requiring more and more treatment of industrial effluents to generate product waters which could be easily reused or disposed of to the environment without any harmful effects. In the present work, the removal of phenol from aqueous solution across polymer inclusion membrane (PIM), based on mixture of cellulose triacetate and cellulose acetate as support (75/25%), calix[4]resorcinarene derivative as a carrier and 2-nitrophenyl octyl ether (2-NPOE) as plasticizer was investigated. The experimental part of this investigation involved the influence of carrier nature, plasticizer concentration, pH phases, and phenol initial concentration on the removal efficiency of phenol from synthetic wastewater. A PIM containing 0.1 g (of mixture polymer), (0.15 g/g mixture of polymer) of carrier and (0.03 ml/g mixture of polymer) of 2-NPOE provided the highest percentage of phenol removal efficiency over a 6-day transport; the removal was found to be about 95%, indeed the removal was found to be highly dependent of pH phases. The feed solution in these transport experiments was at pH 2, while the stripping solution contained 0.20 M NaOH. This study claims that the PIM with a mixture of cellulose derivatives can be used effectively to remove phenols from wastewaters.

Actin is one of the main components of the architecture of cells. Actin filaments form different polymer networks with versatile mechanical properties that depend on their spatial organization and the presence of cross-linkers. Here, we investigate the mechanical properties of actin bundles in the absence of cross-linkers. Bundles are polymerized from the surface of mDia1-coated latex beads, and deformed by manipulating both ends through attached beads held by optical tweezers, allowing us to record the applied force. Bundle properties are strikingly different from the ones of a homogeneous isotropic beam. Successive compression and extension leads to a decrease in the buckling force that we attribute to the bundle remaining slightly curved after the first deformation. Furthermore, we find that the bundle is solid, and stiff to bending, along the long axis, whereas it has a liquid and viscous behavior in the transverse direction. Interpretation of the force curves using a Maxwell visco-elastic model allows us to extract the bundle mechanical parameters and confirms that the bundle is composed of weakly coupled filaments. At short times, the bundle behaves as an elastic material, whereas at long times, filaments flow in the longitudinal direction, leading to bundle restructuring. Deviations from the model reveal a complex adaptive rheological behavior of bundles. Indeed, when allowed to anneal between phases of compression and extension, the bundle reinforces. Moreover, we find that the characteristic visco-elastic time is inversely proportional to the compression speed. Actin bundles are therefore not simple force transmitters, but instead, complex mechano-transducers that adjust their mechanics to external stimulation. In cells, where actin bundles are mechanical sensors, this property could contribute to their adaptability.

Primary Retroperitoneal mucinous cystadenoma (PRMC) is an extremely rare benign tumor, predominantly occurring in women, with unclear pathogenesis.

We have studied the drainage of foams made with viscous solutions. In this way, drainage is slowed down, and microgravity conditions are approached. The behaviour of mixtures of water and glycerol follows the theoretical predictions, but that of aqueous solutions of a polymer (polyethylene oxide) do not : drainage is much faster than for water-glycerol mixtures of the same bulk viscosity. The origin of this puzzling behavior is still not understood.

This paper tries to extend empirically the literature disciplining effect of inflation targeting (IT) monetary policy on fiscal policy. Based on the previous studies including Abo-Zaid and Tuzemen (2011) and Kadria and Ben Aissa (2014) as well as the dynamic panel method (S-GMM) and the treatment effect approach, our contribution is then to evaluate the effect of the IT's adoption by emerging markets on their budgetary discipline in terms of primary budget deficit performance. Our empirical analysis, conducted on a sample of 34 economies (13 IT and 21 non-IT economies) for the period from 1990 to 2010, show that on average IT adoption has had a significant effect in reducing the primary deficit in emerging countries that have adopted this monetary policy framework.

The polymer inclusion membranes (PIMs) containing Cellulose triacetate as polymer base, 2-NPOE as a plasticizer, and Calix[4]resorcinarene (RC8) as a carrier were prepared and characterized. Microstructure and surface of PIMs were characterized by scanning electron microscope, FTIR, UV/vis spectroscopy, and Thermogravimetric Analysis, respectively. In order to obtain information on the composition and interactions that may manifest between the constituents of the membrane. The PIMs were applied in the elimination of Methylene Blue (MB) dye from model solution as synthetic aqueous wastewater. Furthermore, the effects of different parameters such as internal and external PIMs environment on the transport performance of MB were also investigated. The results confirming that the content of the carrier and plasticizer in the membrane had a significant impact on the property of PIMs. The transport of dye was in line with the first-order kinetics equation. The highest flux value "8.88 × 10–7mol.m−2s−1"was obtained with a calix [4] resorcinarene as a transporter in polymer inclusion membrane at pH 11 in the feed and 0.3 M HCl in the stripping phase when MB initial concentration was 100 mg/L. The membrane has better stability under optimum conditions and maximum transport was observed after 30 h of permeation time.

The preovulatory human follicular fluid contains only HDLs as a lipoprotein class with a typically high proportion of preβ HDL. We first examined the role of follicular fluid and HDL subfractions on human spermatozoa capacitation, a process characterized by a hyperactivation of the flagellar movement and a depletion of plasma membrane cholesterol. Whole follicular fluid and isolated HDL, used at constant free cholesterol concentration, were both able to promote an early flagellar hyperactivation. Moreover, incubation of [3H]cholesterol-labeled spermatozoa with follicular fluid induced a rapid cholesterol efflux from spermatozoa that was confirmed by mass measurements of cholesterol transfer. Using isolated HDL, the cholesterol efflux had a similar time course and represented 70% of that mediated by whole follicular fluid. We then analyzed the time course of radioactive labeling of HDL subfractions. In the first minute of incubation, we found that the preβ HDL fraction incorporated the main part of the radioactivity (60%), with the rest being found in α-HDL, but strikingly, the labeling of α-HDL increased with time at the expense of preβ HDL.Thus, our results indicate that HDLs are involved in both spermatozoa hyperactivation and cholesterol effl ux and suggest the role of preβ-HDL particles as fi rst cellular cholesterol acceptors.

The preovulatory human follicular fluid contains only HDLs as a lipoprotein class with a typically high proportion of preβ HDL. We first examined the role of follicular fluid and HDL subfractions on human spermatozoa capacitation, a process characterized by a hyperactivation of the flagellar movement and a depletion of plasma membrane cholesterol. Whole follicular fluid and isolated HDL, used at constant free cholesterol concentration, were both able to promote an early flagellar hyperactivation. Moreover, incubation of [3H]cholesterol-labeled spermatozoa with follicular fluid induced a rapid cholesterol efflux from spermatozoa that was confirmed by mass measurements of cholesterol transfer. Using isolated HDL, the cholesterol efflux had a similar time course and represented 70% of that mediated by whole follicular fluid. We then analyzed the time course of radioactive labeling of HDL subfractions. In the first minute of incubation, we found that the preβ HDL fraction incorporated the main part of the radioactivity (60%), with the rest being found in α-HDL, but strikingly, the labeling of α-HDL increased with time at the expense of preβ HDL.Thus, our results indicate that HDLs are involved in both spermatozoa hyperactivation and cholesterol effl ux and suggest the role of preβ-HDL particles as fi rst cellular cholesterol acceptors.

The mammalian target of rapamycin (mTOR) is emerging as a promising target for antitumor therapy. However, the mechanism that contributes to its regulation in B lymphomas remains unknown. This study shows that in follicular lymphoma (FL) cells, mTOR is active because the cells displayed rapamycin-sensitive phosphorylation of p70S6 kinase and 4E-BP1. Moreover, immunohistochemistry applied on lymph node tissue sections obtained from patients with FL revealed that, in most cases, p70S6 kinase was highly phosphorylated compared to normal tonsillar tissue. In FL cells, mTOR was under control of both phospholipase D (PLD) and phosphatidylinositol 3-kinase (PI3K). Moreover, we demonstrated that Syk plays a central role in mTOR activation because we found that both expression and activity are elevated compared to normal or chronic lymphocytic leukemia B cells. We also provide evidence that Syk operates through PLD- and PI3K-independent pathways. Finally, Syk inhibition by piceatannol or by siRNA plasmids resulted in a potent inhibition of mTOR activity in FL cells, as well as in mantle cell lymphoma, Burkitt lymphoma, and diffuse large B-cell lymphoma. These findings suggest that the Syk-mTOR pathway has a critical function in FL survival, and therefore, that Syk could be a promising new target for B-lymphoma therapy.

The mammalian target of rapamycin (mTOR) is emerging as a promising target for antitumor therapy. However, the mechanism that contributes to its regulation in B lymphomas remains unknown. This study shows that in follicular lymphoma (FL) cells, mTOR is active because the cells displayed rapamycin-sensitive phosphorylation of p70S6 kinase and 4E-BP1. Moreover, immunohistochemistry applied on lymph node tissue sections obtained from patients with FL revealed that, in most cases, p70S6 kinase was highly phosphorylated compared to normal tonsillar tissue. In FL cells, mTOR was under control of both phospholipase D (PLD) and phosphatidylinositol 3-kinase (PI3K). Moreover, we demonstrated that Syk plays a central role in mTOR activation because we found that both expression and activity are elevated compared to normal or chronic lymphocytic leukemia B cells. We also provide evidence that Syk operates through PLD- and PI3K-independent pathways. Finally, Syk inhibition by piceatannol or by siRNA plasmids resulted in a potent inhibition of mTOR activity in FL cells, as well as in mantle cell lymphoma, Burkitt lymphoma, and diffuse large B-cell lymphoma. These findings suggest that the Syk-mTOR pathway has a critical function in FL survival, and therefore, that Syk could be a promising new target for B-lymphoma therapy.

Exosomes are small vesicles secreted from multivesicular bodies, which are able to stimulate the immune system leading to tumour cell eradication. We have analysed lipids of exosomes secreted either upon stimulation from rat mast cells (RBL-2H3 cells), or constitutively from human dendritic cells. As compared with parent cells, exosomes displayed an enrichment in sphingomyelin, but not in cholesterol. Phosphatidylcholine content was decreased, but an enrichment was noted in disaturated molecular species as in phosphatidylethanolamines. Lyso(bis)phosphatidic acid was not enriched in exosomes as compared with cells. Fluorescence anisotropy demonstrated an increase in exosome-membrane rigidity from pH 5 to 7, suggesting their membrane reorganization between the acidic multivesicular body compartment and the neutral outer cell medium. NMR analysis established a bilayer organization of exosome membrane, and ESR studies using 16-doxyl stearic acid demonstrated a higher flip-flop of lipids between the two leaflets as compared with plasma membrane. In addition, the exosome membrane exhibited no asymmetrical distribution of phosphatidylethanolamines. Therefore exosome membrane displays a similar content of the major phospholipids and cholesterol, and is organized as a lipid bilayer with a random distribution of phosphatidylethanolamines. In addition, we observed tight lipid packing at neutral pH and a rapid flip-flop between the two leaflets of exosome membranes. These parameters could be used as a hallmark of exosomes.

In this paper, we examine the order of magnitude of the octonion Fourier transform (OFT) for real-valued functions of three variables and satisfiying certain Lipschitz conditions. In addition, using the analog of the operator Steklov, we construct the generalized modulus of smoothness, and also using the Laplacian operator we define the K-functional. We use the octonion Fourier transform (OFT) of real-valued functions of three variables to prove the equivalence between K-functionals and modulus of smoothness in the space of square-integrable functions (in Lebesgue sense).