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The novel hyphenation of electrospray-differential mobility analysis with single particle inductively coupled plasma mass spectrometry (ES-DMA-spICPMS) was demonstrated with the capacity for real-time size, mass, and concentration measurement of nanoparticles (NPs) on a particle-to-particle basis. In this proof-of-concept study, the feasibility of this technique was validated through both concentration and mass calibration using NIST gold NP reference materials. A detection limit of 10(5) NPs mL(-1) was determined under current experimental conditions, which is about 4 orders of magnitude lower in comparison to that of a traditional ES-DMA setup using a condensation particle counter as detector. Furthermore, independent and simultaneous quantification of both size and mass of NPs provides information regarding NP aggregation states. Two demonstrative applications include gold NP mixtures with a broad size range (30-100 nm), and aggregated gold NPs with a primary size of 40 nm. Finally, this technique was shown to be potentially useful for real-world samples with high ionic background due to its ability to remove dissolved ions yielding a cleaner background. Overall, we demonstrate the capacity of this new hyphenated technique for (1) clearly resolving NP populations from a mixture containing a broad size range; (2) accurately measuring a linear relationship, which should inherently exist between mobility size and one-third power of ICPMS mass for spherical NPs; (3) quantifying the early stage propagation of NP aggregation with well-characterized oligomers; and (4) differentiating aggregated NPs and nonaggregated states based on the apparent density derived from both DMA size and spICPMS mass.

In this paper, we present a complete and efficient solution of guidance, navigation and control for a quadrotor platform to accomplish 3D coverage flight missions in mapped vineyard terrains. Firstly, an occupancy grid map of the terrain is used to generate a safe guiding coverage path using an Iterative Structured Orientation planning algorithm. Secondly, way-points are extracted from the generated path and added to them trajectory’s velocities and accelerations constraints. The constrained way-points are fed into a Linear Quadratic Regulator algorithm so as to generate global minimum snap optimal trajectory while satisfying both the pointing and the corridor constraints. Then, when facing unexpected obstacles, the quadrotor tends to re-plan its path in real-time locally using an Improved Artificial Potential Field algorithm. Finally, a geometric trajectory tracking controller is developed on the Special Euclidean group SE(3). The aim of this controller is to track the generated trajectory while pointing towards predetermined direction using the vector measurements provided by the inertial unit. The performance of the proposed method is demonstrated through several simulation results. In particular, safe guiding paths are achieved. Obstacle-free optimal trajectories that satisfy the way-point position, the pointing direction, and the corridor constraints, are successfully generated with optimized platform snap. Besides, the implemented geometric controller can achieve higher trajectory tracking accuracy with an absolute value of the maximum error in the order of 10−3 m.

Introduction. The Moroccan energy system is highly dependent on external energy markets. This is why the current Moroccan energy strategy is focused on deployment of renewable technologies projects. Morocco has abundant wind resources. The purpose of this publication is identifying the characteristics of wind regime in Tangier in 2021-2050 to assess the wind potential. Results. This particular study used the data of regional climate modelling (RCM) with high spatial resolution of the CORDEX project. The article contains the results of RCM modelling using the RCP 4.5 scenario presented in the rectangular coordinate system with spatial resolution of ≈ 44 km. An ensemble of 11 climatic models was used for the analysis. To verify the RCM retrospective simulations for the period of 2011-2016 were used and to verify the RCM forecasts associated with wind speed we used the observations made at the Tangier meteorological station. The performed analysis allows us to conclude that average ensemble-based series of average monthly values are close to average values of the observed meteorological parameters. The models reflect the climatic parameters with varying degrees of accuracy and their results can be used to analyze future conditions of the climatic system in this region. Average wind speed for the period of 2021-2050 at the Tangier station will be equal to 5.1 m/s which exceeds the current value of 0.6 m/s. According to the forecast the wind speed in the territory of Tanger – Tetouan − Al Hoceima region will exceed 4.5 m/s. Comparison of the RCM-calculated wind speed value with the observational data for the period of 2005-2014 showed its increase. Based on the average annual wind speed values in each of the grid's nodes the linear regression coefficients were calculated. Conclusion. RCM-modelling showed that in 2021-2050 the territory of Tanger – Tetouan − Al Hoceima region will be dominated by the conditions being favourable for operation and further development of wind energy. Comparison of model calculations with observational data of the current climatic period showed that the Strait of Gibraltar area and the adjacent territories will see the wind speed increase in the future. The maximum value of wind speed annual run will be observed during the cold period of the year which coincides with the period of increased demand for electricity by its consumers. Directions of further research. The results of this study will be used as the basis for calculating the wind power in this region in 2021-2050.

Quand on évoque la gouvernance de l’entreprise familiale, il s’agit rarement de traiter du sujet du conseil de famille et de la charte familiale. Pourtant, parallèlement à l’organe de direction chargé de la gouvernance du sous-système entreprise, le conseil de famille joue un rôle d’interface entre les deux sous-systèmes, famille et entreprise. D’une part, il permettra de maximiser le profit que peut tirer l’entreprise de la dimension familiale puisque cette dernière peut constituer un facteur clé de succès. D’autre part, le conseil de famille permettrait à l’entreprise d’éviter les retombées négatives d’un manque de cohésion et de vision chez la famille propriétaire. Un tour d’horizon sur le sujet du conseil de famille, sous forme d’un essai, s’impose alors tant le sujet se révèle stratégique pour les entreprises familiales.

Some studies found that the proportions of cocoa butter (CB), cocoa butter equivalent (CBE) and milk fatty acid (AMF) tend to influence the blooming delay when mixing them. The goal of our research is to determine the effects of the proportion of CB, CBE and AMF on the structural organization of the final mixtures. X-ray, DSC, MIR and Raman spectroscopy were used to analyze the structural features and the vibrational modes of four mixtures: CB + 0.5AMF, CB + AMF, CB + 0.5AMF + CBE and CB + AMF + CBE. At room temperature, the triglycerides are ingredients of CB, and CBE and AMF do not fully exhibit the known crystalline forms V or VI, unlike a recent CB sample. Part of these triglycerides is in the form IV instead. The presence of the latter seems to be a key parameter that favors the deceleration of the transformation to the form VI, which is responsible for the development of fat bloom.

We study the shadow behaviors of five dimensional (5D) black holes embedded in type IIB superstring/supergravity inspired spacetimes by considering solutions with and without rotations. Geometrical properties as shapes and sizes are analyzed in terms of the D3-brane number and the rotation parameter. Concretely, we find that the shapes are indeed significantly distorted by such physical parameters and the size of the shadows decreases with the brane or “color” number and the rotation. Then, we investigate geometrical observables and energy emission rate aspects.

We investigate the thermodynamic properties of the Hawking-Page phase transition of AdS black holes. We present evidence for the existence of two universal critical constants associated with the Hawking-Page (HP) and minimum black hole thermodynamical transition points. These constants are defined by CS=SHP−SminSmin and CT=THP−TminTmin where Smin(SHP) and Tmin(THP) are the minimal (HP phase transition) entropy and temperature, respectively, below which no black hole can exist. For a large class of four dimensional non-rotating black holes, we find CS=2 and CT=2−33. For the rotating case, however, such universal ratios are slightly affected without losing the expected values. Taking small values of the involved rotating parameter, we recover the same constants. Higher dimensional models, with other universal constants, are also discussed in some details.

A compact triple band antenna by using etching slots technique in the radiation element is presented in this paper. The proposed antenna is designed to target three different frequencies: 7.5 GHz (military satellite communication), 9 GHz (radar applications) and 28 GHz (fifth generation applications). The fabricated prototype of the antenna has overall dimensions of 13x12.8x1.6 mm3. Measurements were carried out to validate the simulation results. The impedance bandwidths are 259 MHz (7.435-7.695 MHz), 355 MHz (8.86-9.221 MHz) and 2.67 GHz (26.79-29.433 GHz) with return loss less than -10 dB. Furthermore, the suggested antenna provides a gain of 3.96 dBi, 3.05 dBi and 5.86 dBi at 7.5 GHz, 9 GHz and 28 GHz respectively. Therefore, the results demonstrate that the proposed triple band antenna can be used for military satellite communication, radar applications and is a good candidate for the future 5G applications.

Hygroscopic materials which possess high moisture adsorption capacity were successfully upgraded by the functionalization of sodium chloride (NaCl) using two nuances of oxides. A procedure was developed to first prepare submicron-sized NaCl crystals; thereafter, these crystals were coated by choice of either titanium dioxide (TiO2) or silica (SiO2) to enhance the hygroscopic properties of NaCl and prevent its premature deliquescence. After coating, several analytical techniques were employed to evaluate the obtained composite materials. Our findings revealed that both composites NaCl-TiO2 and NaCl-SiO2 gave excellent performances by exhibiting interesting hydrophilic properties, compared to the sole NaCl. This was demonstrated by both environmental scanning electron microscope (ESEM) and water vapor adsorption experiments. In particular, NaCl-TiO2 composite showed the highest water adsorption capacity at low relative humidity and at a faster adsorption rate, induced by the high surface energy owing to the presence of TiO2. This result was also confirmed by the kinetics of adsorption, which revealed that not only does NaCl-TiO2 adsorb more water vapor than NaCl-SiO2 or sole NaCl but also the adsorption occurred at a much higher rate. While at room temperature and high relative humidity, the NaCl-SiO2 composite showed the best adsorption properties making it ideal to be used as a hygroscopic material, showing maximum adsorption performance compared to NaCl-TiO2 or sole NaCl. Therefore, NaCl-TiO2 and NaCl-SiO2 composites could be considered as promising hygroscopic materials and potential candidates to replace the existing salt seeding agents.

This paper presents a compact Multiple Input Multiple Output antenna with high isolation and low envelope correlation (ECC) for fifth-generation applications using spatial diversity technique. The proposed MIMO antenna consists of two single antennas, each having size of 13 × 12.8 mm2, symmetrically arranged next to each other. The single and MIMO antennas are simulated and analyzed. To verify the simulated results, the prototype antennas were fabricated and measured. A good agreement between measurements and simulations is obtained. The proposed antenna covers the 28 GHz band (27.5–28.35 GHz) allocated by the FCC for 5G applications. Moreover, the isolation is more than 35 dB and the ECC is less than 0.0004 at the operating band, which means that the mutual coupling between the two elements is negligible. The MIMO parameters, such as diversity gain (DG), total active reflection coefficient (TARC), realized gain, and efficiency, are also studied. Thus, the results demonstrate that our antenna is suitable for 5G MIMO applications.

A compact wide-band Multiple Input Multiple Output (MIMO) antenna having highest isolation and least correlation for millimeter-wave 5G communications is proposed in this paper. Firstly, a single antenna was designed and simulated to be working at 38 GHz, a potential target band for 5G applications. It consists of a 5-shaped radiating patch, with partial ground plane. Its length is adjusted and a wide bandwidth is obtained. Then, the two antenna elements are closely positioned with edge-to-edge spacing of 1 mm (0.55 λ, with λ is the free space wavelength at resonance). Thanks to the technique of spatial diversity, a high degree of isolation is attained; more than 25 dB in the whole bandwidth. Moreover, correlation value is under 0.0002 in the working band. The prototype antennas are fabricated and measured. The result indicates that this antenna shows a reflection coefficient under -10 dB over a range of frequencies from 32.3 to 54.6 GHz (BW=22.3 GHz, 58.68% fractional bandwidth). The antenna presents a high realized gain of 7.12 dBi and radiation efficiency of about 82.46% at the desired frequency. Due to these results, our antenna may be regarded a suitable candidate for mm-wave 5G MIMO applications.

The Moroccan energy system is highly dependent on external energy markets. The use of solar energy is one of the most promising ways in the development of renewable energy sources. At the moment, there are several scenarios for the development of renewable energy in Morocco diverging only in quantitative assessments. All of them are aimed at increasing the generation of green energy, from the complete satisfaction of all needs of Moroccan consumers to the opportunity of exporting some of its environmentally friendly electricity to Europe. Estimation of energy efficiency of solar installations is usually carried out on the basis of calculations of solar radiation arrival in the presence of cloudless sky. Clouds significantly reduce amount of solar radiation and sunshine duration. This study is aimed at determination of possible quantitative parameters of the total cloud cover and the areas in which the cloud cover would have the least impact on the amount of incoming solar radiation in Morocco in 2020-2050. The article presents the results of simulation of total cloud fraction using 11 regional climate models of CORDEX project for the period of 2020-2050 in Morocco. For the period of 2020-2050 the average values of total cloud fraction on the territory of Morocco will have the smallest values within the plains located near the border with Algeria on the territory of the prefecture of Sous-Massa lying at the foot of the southern slopes of the Anti-Atlas. The analysis of the annual regime of total cloud fraction showed that in the future it will be of a different nature in different parts of the country due to various factors affecting its formation. The area with the smallest volumes of monthly total cloud fraction will lie within the territory the southern part of prefecture Draa-Tafilalet and prefectures Sous-Massa, Guelmim-Oued Noun, Laayoune-Sakia El Hamra, Dakhla-Oued Ed-Dahab excluding their coastal parts of the Atlantic Ocean. In the future most of the territory of Morocco will be characterized by a low amount of total cloud fraction, which, in its turn, will have an insignificant effect on the amount of solar radiation entering to the underlying surface of these areas. In terms of solar power, the best conditions will exist at the southern parts of Morocco, excluding the coast where the total cloud fraction will have the least impact on the amount of solar radiation reaching the earth’s surface and on sunshine duration.

Atherosclerosis is a leading cause of cardiovascular diseases (CVD) worldwide and intimately linked to aging. This pathology is characterized by chronic inflammation, oxidative stress, gradual accumulation of low-density lipoproteins (LDL) particles and fibrous elements in focal areas of large and medium arteries. These fibrofatty lesions in the artery wall become progressively unstable and thrombogenic leading to heart attack, stroke or other severe heart ischemic syndromes. Elevated blood levels of LDL are major triggering events for atherosclerosis. A cascade of molecular and cellular events results in the atherosclerotic plaque formation, evolution, and rupture. Moreover, the senescence of multiple cell types present in the vasculature were reported to contribute to atherosclerotic plaque progression and destabilization. Classical therapeutic interventions consist of lipid-lowering drugs, anti-inflammatory and life style dispositions. Moreover, targeting oxidative stress by developing innovative antioxidant agents or boosting antioxidant systems is also a well-established strategy. Accumulation of senescent cells (SC) is also another important feature of atherosclerosis and was detected in various models. Hence, targeting SCs appears as an emerging therapeutic option, since senolytic agents favorably disturb atherosclerotic plaques. In this review, we propose a survey of the impact of inflammation, oxidative stress, and senescence in atherosclerosis; and the emerging therapeutic options, including thioredoxin-based approaches such as anti-oxidant, anti-inflammatory, and anti-atherogenic strategy with promising potential of senomodulation.

Painful diabetic neuropathy is a frequent complication of diabetes. Its diagnosis is clinical. Our goal is to determine the prevalence of painful diabetic neuropathy in this population. We also analyzed the relationship between this neuropathy and certain parameters, concerning the patient and his diabetes. It is a cross sectional study conducted at the department of endocrinology and internal medicine of Avicenne hospital Marrakech-Morocco, among a cohort of 300 diabetic outpatients. We used the DN4 questionnaire (Douleur Neuropathique en 4 questions), for diagnosis. The results showed a prevalence of 15%. In this study: advanced age, female gender, duration of diabetes greater than 10 years, and the lack of medical follow up were found to be statistically significant risk factors for painful diabetic neuropathy, in addition to some diabetes-related comorbidities such as hypertension, dyslipidemia, sedentary life style and diabetic retinopathy. Painful diabetic neuropathy remains undertreated, in fact 74% of our patients did not receive any specific treatment, knowing that the progress in developing effective and well-tolerated therapies has been disappointing.