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Considerable research efforts have been dedicated to comprehensively evaluate the electrochemical and photocatalytic properties of newly synthesized metal sulfides. This research aims to determine the viability of using metal sulfide, MnS2:Ni9S8:Co3S4thin film with excellent energy retention capacities and amazing photocatalytic activities. Single source precursor method was utilized for the synthesis of metal sulfide. Furthermore, deposition of thin film was performed through physical vapour deposition route. Detailed characterization was done by using UV‐visible spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction crystallography and X‐ray photoelectron spectroscopy. Electrochemical investigation was done through cyclic and linear sweep voltammetry while competence of the thin film in degrading various environmental pollutants, including crystal violet dye, fuberidazole and phenol, was evaluated by photocatalytic degradation. A crystallite size of 47 nm with 86.5% crystallinity was found along with a 3.4 eV bandgap energy. Round‐edged cubical structures in the composite were seen. X‐ray photoelectron spectroscopy revealed core level peaks of Mn 2p, Ni 2p, Co 2p and S 2p. A specific capacitance of 590 Fg−1was observed from the electrochemical analysis showing the presence of electroactive sites that allow for effective electrochemical processes. After 60 minutes of exposure to the thin film, phenol showed the slowest rate of degradation, whereas crystal violet and fuberidazole showed significant percentages of deterioration. The findings highlight MnS2:Ni9S8:Co3S4thin film's adaptability as viable compound for addressing the critical concerns of storing energy, production, and environmental cleanup. These significant findings highlight the versatility of tri‐metal sulfide thin films, opening up avenues for further research and technological advancements. Single source precursor method was utilized for the synthesis of MnS2:Ni9S8:Co3S4thin film. Its remarkable electrochemical and photocatalytic applications presented its adaptability as viable for addressing the critical concerns of storing energy, production, and environmental cleanup.

In electronic warfare, a robust perception of the surrounding signal environment is vital for optimal countermeasures. In this article, a new approach to a cognitive electronic support measures (COG-ESM) system based on computer vision techniques is proposed. The proposed approach overcomes the limitations of the traditional ESM when subjected to complex radar signals in a dense environment. The proposed approach relaxes the deinterleaving process of the concurrent radar signals to a 2D emitter localization in the time-frequency (TF) domain. Also, it integrates the modulation classification process with the 2D emitter localization in one process. This merge allows for sharing the hardware and software assets required for both processes. The proposed COG-ESM applies the state-of-the-art object detection networks to the TF images to localize and classify the individual radar emitters. The COG-ESM is trained to perform both 2D localization and modulation classification under the multipath effect, hence it is more robust under channel impairments. A new dataset of complex interleaved radar signals representing a dense signal environment under the multipath channel effect is introduced. Typical scenarios, signal parameters, and modulation types are considered in generating the dataset. That dataset is called wideband radar signals in dense environment (WBR-DE).

AbstractThe Mega Housing Projects (MHP) construction in Egypt is saddled with numerous risks that emerged from the risk knowledge dearth, steering these projects to elusive failure apropos to completion time and construction cost. The research's novel contribution is a risk assessment Structural Equation Modeling (SEM) approach that spotlights the critical risk factors confronting MHP in Egypt concerning Probability of Occurrence (POO), Impact on Time (IOT), and Impact on Cost (IOC), from the contractors perspective. Forty-three risk factors were amassed from the literature and lessened to 25, delineating the significant risks impacting the MHP schedule and budget resentfully. The primary paper's objectives are determining the captious risk factors and ranking their relative importance weights. A questionnaire survey was conducted, and distinctive construction professionals solicited feedback. Quantitative data obtained from 103 valid responses were analysed using SEM, and the measurement and structural models were validated. Data analysis revealed that the project management risks procure the prime relative importance weight concerning POO, IOT, and IOC at 32.09%, 26.04%, and 32.93% mutually. Findings will equip contractors with a model to pinpoint and rank the censorious risk factors impacting the MHP to prioritise allotting budgetary scenarios among risks to vanquish cost and time overruns.

An unprecedented use of plastics has caused many environmental issues, and as usual, there is a growing interest in recycling and reusing single-use household plastics. In this work, a mixture of five prominent plastic polymers, as simulated household waste, was depolymerized via the hydrothermal liquefaction (HTL) process using a pretreated red mud catalyst (RM) for the liquid product at 430 ± 20 °C reaction temperature for an average 2 h residence time. The selected plastics were polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS), which were blended at a ratio of 42, 20, 20, 4, and 14 wt %, respectively, to form a plastic mixture (PM) as a simulated household plastic waste. Additionally, each plastic type was treated individually for control experiments. Among the single plastics, HDPE generated a maximum crude oil yield of 76 wt %, whereas PET produced mainly solid (80 wt %) and gaseous products. The crude oil yield production from noncatalytic reactions followed this trend: HDPE > PS > PP > LDPE. The plastic crude oil possessed 36–92 wt % gasoline-range compounds. Without a catalyst, HDPE decomposed into straight-chain alkanes, whereas PP- and PS-derived products consisted of cyclic compounds. The noncatalytic PM HTL reaction produced 23 wt % liquid crude product and 23 wt % solid from PET. Though the use of a catalyst decreased the single plastic crude yield by 5–60%, it reduced viscosity by 20–80%, minimized acidity by 14–57%, and increased low boiling products (gasoline range) of HTL oil by 5–80%. The use of the RM catalyst increased the crude yield of PM by 63%, decreased solid output from PET by 10%, improved energy recovery by 4.7%, promoted aromatization in PM-derived crudes by 11.4%, and increased the gasoline boiling range compounds by 18.3%. Additionally, the RM catalyst was recycled without significant change in the PM crude yield. This liquefaction study can help in mitigating plastic recycling issues with liquid fuel production.

Nanoparticles synthesised using natural resources is a cost-effective and ecofriendly technique with a number of advantages. In current work, silver nanoparticles (AgNPs) have been synthesized using the extract of Fragaria ananassaseeds. The extract was used as a source of phytochemicals that can act as reducing and stabilizing agents. The characteristics of AgNPs were determined by UV/Visible, FTIR, SEM, XRD and Dynamic light scattering (DLS) techniques. The appearance of the distinctive absorption peak in UV-visible spectra at 430 nm confirmed the formation of AgNPs. The involvement of different bioactive functional groups with AgNPs was authenticated by FTIR studies. Particle size and morphology was confirmed by DLS, SEM and XRD analysis. The catalytic potential of AgNPs for the removal of poisonous organic dyes, brilliant green (BG) and methyl orange (MO) was also tested. Effect of different parameters including the catalyst concentration, dyes concentration and presence of different salts on the degradation of dyes was investigated. Nano-size and well-distributed nature of AgNPs, BG and MO dyes were degraded rapidly individually as well as simultaneously. The degradation process obeyed pseudo first order kinetics. Authors concluded that AgNPs synthesized using environment friendly and cost-effective method, can be used as a new tool to combat pollution caused by carcinogenic organic dyes.

Electrochemical faradic deionization (EDI), one of the most promising research branches of capacitive deionization (CDI), has demonstrated considerable potential for water desalination and ion removal (particularly at medium to low salinity). However, the associated relatively slow anion-capturing kinetics have limited the practical applications of EDI. Based on several studies, researchers have attributed this slow anion-capturing rate to the sluggish conversion-reaction-induced anion-capturing process (as most anion-capturing electrodes belong to the conversion type). Herein, we report a strategy for accelerating the anion-capturing process to enhance the desalination rate of EDI by utilizing an intercalation-type FeOOH electrode. The chloride-driven EDI system equipped with hollandite-type FeOOH nanospindles is found to present a high desalination rate (up to 4.44 mg g−1min−1) and desalination capacity (51.77 mg g−1). The current study can inspire the future design of ultrafast EDI systems and bring the EDI technique closer to its practical application.An anion-driven electrochemical deionization system equipped with hollandite-type FeOOH nanospindle electrodes is successfully constructed based on the reversible chloride intercalation reaction, and the system is found to demonstrate outstanding desalination performance with a high desalination capacity and rate.

Despite the fact that entrepreneurial orientation (EO) is widely studied in specific literature, little has been done to understand the ability to teach EO, or address the factors that could affect the adoption of such an important strategic entrepreneurial attitude. In this study, we used hierarchical linear regression to test the moderating effect of human capital factors on the relationship between entrepreneurship training and EO. We tested the research hypotheses on 1,330 micro-entrepreneurs who had been previously trained on entrepreneurial attitudes. We found no moderating effect of any of the tested human capital factors such as age, gender, education level, or previous work/job experience. The uniqueness of this study lies in its attempt to investigate the moderating effect of human capital factors on the relationship between entrepreneurship training and EO. According to the findings of this study, we concluded that entrepreneurs can learn and adopt entrepreneurial orientation in their businesses regardless of age, education level, gender, or work experience.

Current electrochemical energy storage technology necessitates the development of a single energy system capable of meeting the high electrochemical efficiency demands of high energy density, power density, and long cyclic stability. To meet these requirements, it is highly desirable to develop new energy storage materials as well as understand the multiple charge storage mechanism in these materials. In this study, titanium dioxide‑zinc vanadate nanocomposites were synthesized as high electrochemical efficiency electrode materials. The electromechanical measurements showed an improved specific capacity of 525 Cg−1for TiO2/Zn3V2O8nanocomposite as compared to 400 Cg−1for Zn3V2O8at a current density of 1 Ag−1. The outstanding power density of 6562 WKg−1with 66 WhKg−1energy density was attained at 1 Ag−1. Moreover, the assembled device shows excellent performance by achieving 114.11 Whkg−1energy density and 2600 Wkg−1power density at 1 Ag−1. The practical viability of the device is demonstrated by fabricating the asymmetric coin cell which can operate the commercially available calculator for ~21 min. Additionally, MATLAB simulations at different voltage step potentials are performed to elucidate the charge storage mechanism which shows higher accuracy as compared with the conventional methods.

The purpose of this study was to investigate the most important determinants of an organisation's sustainable long-term performance. We employed two models together, the data envelopment analysis (DEA) and the relative variety analysis (RVA). DEA was used as the measurement of efficiency. Furthermore, RVA was used to measure flexibility. We tested the main hypotheses in this study using ordinary least square estimation with the consideration of any confounding effect. This study showed that neither organisation efficiency nor organisation flexibility alone cannot explain the variation in long-term performance alone. Furthermore, the results displayed the necessity of combining the organisation efficiency with organisation flexibility together in order to explain the variety of the organisation's long-term performance. Moreover, this study highlighted the importance of flexibility and efficiency in achieving a sustainable long-term performance. In addition, this study contributes to the literature by using recent practical tools like the RVA applied on a real-life data.

This work deals with Human Resource Scheduling Problem (HRSP) where fairness is a very important factor when assigning different shifts to the seafaring teams. This type of problem is part and partial of the NP-hard problems category. We propounded to work out this Seafaring Staff Scheduling Problem (SSSP) using one of the population-based meta-heuristics called Cuckoo Optimization Algorithm (COA), one of the newest, most robust and most popular bio-inspired algorithms. rnAffording schedules that ensure an enhanced staff rest to the company compared to the traditionally used ones was the main objective of the paper. The results indicate that this method outperforms the traditional one in solving this NP -hard problem. In addition, they prove the COA performance in the improvement of the objective function value compared to the previously proposed methods in the literature namely GRASP and ABC. Finally, the use of the COA in scheduling also increased the total posts to be assigned by one compared to the ABC method.

Patient satisfaction is an important and commonly used indicator for measuring the quality in a hospital system. The objective of the study is to analyse the patients' satisfaction in the Sfax maternity. A quantitative study was carried out; throw a questionnaire coded via five-point Likert scale, covering 450 patients. The data analysis was conducted using SPSS and AMOS software. The results showed that a patient was less satisfied by the calmness inside the service, the cleanliness of rest rooms, the cleanliness and comfort of the beds, and by the behaviour of the staff. The actions needed to be taken aim to make each person aware about his own role, to pay more attention to patients' requirement, to guarantee a favourable condition for each one (a minimum of calmness and comfort) and to have well-cleaned restrooms. Moreover, effective communication is necessary to ensure that patient's problems and concerns are understood by those providing care.

La radiologie interventionnelle propose des traitements minimalement invasifs guidés par l’image. De nombreux actes peuvent être réalisés en alternative ou complément des traitements médicaux ou chirurgicaux de l’endométriose proposés jusqu’à présent, notamment la cryoablation percutanée. Le guidage précis permet de minimiser les risques de complications pour les patientes tout en améliorant l’efficacité de la cryoablation. L’expertise du radiologue interventionnel reste cruciale pour garantir le succès.

Entrepreneurship education has been acknowledged for its effectiveness in motivating entrepreneurial activities. This creates a motivation to understand the mechanism of entrepreneurship education in inspiring university graduates to become entrepreneurs. In this study, we investigated how the attitude toward entrepreneurship education (ATEE) contributes to the intentions of university students to be entrepreneurs. Specifically, we examined the direct relationships of ATEE (e.g., behavioural, affective, and cognitive) and the indirect relationships via attitude toward entrepreneurship (ATE) and entrepreneurial self-efficacy (ESE) with entrepreneurial intention (EI). In total, 472 third-year, fourth-year, freshly graduated, and postgraduate students (males = 301 and females = 171) at the Faculty of Commerce & Economics, Sana'a University, Yemen, participated in the online survey. Partial Least Squares Structural Equation Modelling (PLS-SEM) was used to analyse the data. The findings of this study showed that the model explained 52 % of the variance in EI. ATEE had a significant direct and indirect relationship with EI, which indicated a partial mediation role of ATE and ESE. Our findings also showed that EI is fostered more via ATE than via ESE, which indicated that the attitude of the students played a significant role in shaping their intention to act entrepreneurially. This study contributed to the existing literature on entrepreneurship education by integrating the effect of ATEE and its behavioural, cognitive, and affective components. It tested the theory of entrepreneurship education in a challenging context and contributed to the generalizability of the entrepreneurship impact on EIs.

Ecology has recently been grasping for relevance in Tunisia. Additionally, the agglomerations are reflecting on the importance of sustainable development. This study carries out a quantitative study in the 'MONOPRIX' food store in Sfax. The data were collected using sustainable development strategies, which are the alternatives, as well as on the identification of the criteria. Subsequently, the classification and the choice of the most suited preferences to the decision-maker have been developed with the TOPSIS method. The results were not satisfied with the DM preferences. To satisfy this need, we have proposed to integrate the Choquet integral who considered the importation of the dependence relations and coalitions between the criteria by using the Shapley index for the reformulation of the mathematical formula in the ponderation step of the classic TOPSIS. This combination has resulted in a new TOPSISIC approach to outline a better strategy for the MONOPRIX food retailers.

Clustering a stream of text documents is an emerging subject of interest since it is widely used in analysing the content in social media and e-journals. The aim is to find a certain structure for unlabelled data based on a similarity criterion. However, few works have focused on this field and fall in this perspective, that's why a new document clustering approach adapted to a stream of text data and test it on news articles data sets is proposed. A distributed representation of words is used, and a bottom-up approach is used to represent documents as vectors on a unit hyper-sphere. The proposed approach gains its roots from the SPherical k-means (SPKM) algorithm and its underlying mixture of von-Mises Fisher (vMF) distributions. The proposed approach yields comparable results to baseline batch algorithm for stable data streams and superior results for rapidly evolving data streams.

Nuclear magnetic resonance is one of the rare techniques able to probe selectively the ions inside the nanoporous network in supercapacitor devices. With a magnetic resonance imaging method able to detect all ions (adsorbed and nonadsorbed), we record one-dimensional concentration profiles of the active ions in supercapacitors with an electrode configuration close to that used in industry. Larger anionic concentration changes are probed upon charge and discharge in a carbide-derived carbon (CDC) with micropores smaller than 1 nm compared to a conventional nanoporous carbon (CC) with a larger distribution of pore sizes, up to 2 nm. They highlight the increased interaction of the anions with CDC and provide a better understanding of the enhanced capacitance in CDC-based supercapacitors.

Embolization and percutaneous ablations became well-established therapeutic options for hepatocellular carcinomas (HCC). All are performed under minimally invasive conditions using imaging guidance. Selection of a technique over another follows guidelines but also patient's status and availability of the techniques. The aim of this review is to present these techniques performed in routine to treat HCC and to report the outcomes.

The rise in incidentally discovered small renal neoplasms has focused attention on nephron-sparing treatment strategies including partial nephrectomy and percutaneous ablation as well as active surveillance. As all treatment modality, renal ablation has matured technically. Radiofrequency ablation, microwave ablation or cryoablation are now performed in many institutions under imaging guidance. The long-term results allow them to be now recommended as a therapeutic option whatever the patients’ condition if complete ablation can reliably be achieved.

Electrochemical energy storage (EES) systems are gaining prominence as a solution to the issue of conventional energy supply while also reducing environmental pollutants. Electrode morphological engineering is one approach to improving EES device performance in terms of specific capacity, energy density, and power density. Bismuth compounds are interesting because of their enormous reserves and high theoretical capacity for use as anodes in aqueous alkaline batteries and supercapacitors. Here, a hydrothermal technique embeds Ni(OH)2nanosheets into Bi2O2CO3flakes to alter their morphology. This creates garland structures with an equal molar ratio of Bi to Ni sources. In conjunction with the mesopores of the distinctive shape, the interconnected petals offer excellent electron and ion transit channels. Furthermore, the tightly integrated garland structures enhance the stability of the crystal structure, which may improve the electrochemical stability. It has a higher specific capacity of 232.87 mAh g−1at a current density of 0.5 A g−1and is very stable during cycling (remaining 85.12 % of the initial capacity at 1 A g−1after 5000 cycles). This suggests that Bi2O2CO3@Ni(OH)2garland structures are a viable electrode material for energy storage devices.

In this work, the structural, electronic properties, quantum capacitance (CQ), surface charge density (Q), isosurface charge density difference and bader charge analysis of homo- and hetero-bilayer structures of BP, ZnO, GaN and hexagonal boron nitride forming supercapacitor electrode are studied. The effect of doping of Cu-atom in the substrate of homo- and hetero-bilayer was also investigated to modulate the charge storage and electronic properties of BP. All the properties are calculated theoretically using density functional theory (DFT). DFT-D3 method with the Becke-Johnson damping function is used as the dispersion correction factor for all the calculations. The calculated results find that hetero-bilayer structure gives better results as compared to homo-bilayer structure. In this work, results also revealed that doping of transition atoms significantly enhances the CQand Q of hetero-bilayer structure. For the aqueous system, all the bilayers exhibited asymmetrical behaviour except the BP-ZnO hetero-bilayer. Cu-doped BP-ZnO (1554.8μC/cm2), and Cu-doped BP-HBN (−1438.4μC/cm2) hetero-bilayer structure is best for anode and cathode material. In the case of ionic/organic systems, all bilayers showed asymmetrical behaviour. Cu-doped BP-ZnO (−5250 μC/cm2), and BP-GaN (3660μC/cm2) hetero-bilayer structure is the best cathode and anode material.

Naples assumed an important political and economic role within the region of Campania during the late antique period. LA-ICP-MS data of 285 glass tesserae from the catacomb of San Gennaro in Naples confirm that the surge in building activities in the late fourth and early fifth century CE was accompanied by imports of new materials for the production of mosaic tesserae. Our results from Naples identify a substantial number of Jalame-like Levantine glasses for which there is no parallel within the Italian Peninsula. Only few scattered examples of this type of base glass are found among the published data from Aquileia, Ravenna and the Villa of Faragola, pointing to a link between the supply of glass and the sites' connectivity and economic strength. This seems to have changed after the fifth century. Elemental analyses, combined with SEM-EDS and micro-Raman indicate that the mosaics dating from the fourth to the eighth/ninth century CE in the catacombs of San Gennaro were overwhelmingly made from reused first- to fourth-century Roman base glasses opacified with calcium antimonate. The reuse and recycling of Roman glass and Roman tesserae is a common feature of mosaic assemblages in Italy more generally. The definition of a Roman spectrum tesserae reference group revealed this dependence on old Roman material throughout the first millennium CE.

The present study investigated the preparation of biomatrices from Stipa tenacissimaL. and its valorization for fiberboard application. Resins were produced by extracting lignin from the Stipa tenacissimaL. black liquor by soda process and combining it with glyoxal as crosslinking agent to produce lignin-glyoxal-resin (LGR). The matrix was characterized by several methods, such as FTIR and ATG/ATD, and then mixed with date palm rachis as reinforcing fibers in different proportions of 30 and 50% (w/w with respect to the matrix) to produce biodegradable composite materials. Then, their thermal and mechanical properties were determined, using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The results obtained show that date palm rachis particles were effective in enhancing the thermo-mechanical properties of the thermoset matrix.

Zinc-ion hybrid supercapacitors (ZIHCs) show great potential as advanced energy storage devices. Herein, we present vanadium (V)-doped manganese oxide aerogel structured (V-Mn-O) cathode material with expended interlayer space for ZIHCs. The V-doping expands the interlayer distance of MnO2and creates more active sites with open channels for fast ionic diffusion, and offers good structural stability. The as-fabricated ZIHC (V-Mn-O//Zn) demonstrates a maximum specific capacitance of 333.35 F/g at 1 A/g with capacitance retention of 95.63 % after 10,000 cycles with ∼98 % Coulombic efficiency. The V-Mn-O//Zn exhibits highly capacitive charge storage characteristics. Furthermore, the V-Mn-O//Zn delivers a maximum energy density of 150.12 Wh/kg at a power density of 900.72 W/kg and is superior to most of the previously reported values at similar conditions. This work presents an innovative approach for developing high-rate next-generation zinc-ion hybrid supercapacitors.

The current study compares two damage modeling approaches in metal cutting finite element simulations; the Johnson-Cook shear failure model and the progressive damage model. The first assumes sudden failure when the set criterion is met; however, the second relies on two criteria; one for damage initiation and another for damage evolution. Simulations were performed on AISI 1045 steel, and different process parameters (forces, chip thickness, temperatures and plastic strain) were compared. Also, dry orthogonal cutting tests were performed and cutting forces and chip thickness were compared to the predicted values. The current results showed better predictions when damage evolution was considered.

Déterminer les caractéristiques sociodémographiques et cliniques des patients consultant aux urgences pour tentatives de suicide et identifier les facteurs associés.

Two resins were prepared from Stipa tenacissimaL. and their physical and chemical behaviors were evaluated. The resins were produced by modification of extracted lignin from the S. tenacissimaL. using phenolation reaction (resorcinol). Glyoxal and formaldehyde as cross-linking agents were employed to produce lignin–glyoxal resin and lignin–resorcinol–formaldehyde resins (LRFR), respectively. The curing process of two lignin-based resins (lignin–resorcinol–glyoxal, LRGR, and lignin–resorcinol–formaldehyde, LRFR) was studied by rheological measurements and differential scanning calorimetry (DSC) techniques, which showed that the gel formation obeys an isoconversional principle. In fact, an analysis on curing kinetics was performed by processing its non-isothermal DSC data using Ozawa’s isoconversional methods and found that good fittings could be obtained. This method allowed the determination of activation energy and the pre-exponential factor dependencies on the degree of curing. In kinetics method, the variation in activation energy, evaluated at different curing degrees, revealed that the mechanism of phenolic resins is based on two reactions: methylolation followed by condensation. Finally, the gel points of these systems were found to be around 63 and 72 %, for LRFR and LRGR, respectively. These values were compared to those calculated from Flory and Stockmayer equation and found to be close to each other.

This paper treats a problem of sealing teams’ scheduling where the equity between them is the main objective specifically at the level of journeys bonuses which varies for each occupied post. Indeed, there are three types of posts: permanent posts, special posts which are booked for fuels and hazardous goods transportation and reinforcement posts if needed. The interval of weekly rest hours and the interval of hours between consecutive posts present an important criterion for the problem. We provide a mathematical formulation of the problem based on the goal programming in which we adapt an analytical hierarchy process method to determine weights of various objectives. Also, we provide the adaptation of the GRASP method to resolve the real cases. It is worth mentioning that we used a real data of a Tunisian company called SONOTRAK.

AbstractExperts from all continents discussed the present and future of nephrology and transplantation medicine in emerging countries during a 3-day conference, supported by the World Health Organization, the International Society of Nephrology, the Transplantation Society – Global Alliance for Transplantation and the Ministry of Health of the Republic of Mali. This conference was held in Bamako, Mali on December 4–6, 2008, and focused on prevention and treatment of chronic kidney disease in emerging countries. Apart from delivering high-quality medical and scientific knowledge, the meeting was mainly a call to action for emerging countries to start chronic kidney disease prevention and screening programs, develop end-stage renal disease registries and start or further elaborate transplantation programs. International as well as regional collaborations need to be stimulated and strengthened in order to allow emerging countries to acquire the information, technology, experience and skills necessary to achieve these ambitious goals.Copyright © 2010 S. Karger AG, Basel

Within the literature of entrepreneurship and entrepreneurship training, several studies have discussed the nature of entrepreneurship orientation, measurement, and importance. Others studied the relationship between entrepreneurship training and entrepreneurial intention. They discussed the ability of entrepreneurship training to encourage individuals starting their own business. Little has been done to study the relationship between entrepreneurship training and entrepreneurial orientation. Utilizing a quasi-experimental approach of the sharp regression discontinuity design as the most rigorous alternative to experimental schemes, we tested the relationship using a sample of 1330 micro-sized firms. After choosing the optimal test bandwidth, the regression discontinuity design assigned 342 observations to the control group and 382 observations to the treatment group. We found positive and significant causal relationships between entrepreneurship training and all three dimensions of entrepreneurial orientation. This study contributes to filling the gap in the entrepreneurship literature in two folds. First, it is the first study that addresses the effect of entrepreneurship training on entrepreneurial orientation as a viable business strategy. Second, it studied the causal relationship between entrepreneurship training and entrepreneurial orientation in micro-sized businesses as the most in need of such an entrepreneurial experience. Finally, Theoretical and managerial implications are discussed.

Specific forms of fatty acids are well known to have beneficial health effects, but their precise mechanism of action remains elusive. Phosphatidic acid (PA) produced by phospholipase D1 (PLD1) regulates the sequential stages underlying secretory granule exocytosis in neuroendocrine chromaffin cells, as revealed by pharmacological approaches and genetic mouse models. Lipidomic analysis shows that secretory granule and plasma membranes display distinct and specific composition in PA. Secretagogue-evoked stimulation triggers the selective production of several PA species at the plasma membrane near the sites of active exocytosis. Rescue experiments in cells depleted of PLD1 activity reveal that mono-unsaturated PA restores the number of exocytotic events, possibly by contributing to granule docking, whereas poly-unsaturated PA regulates fusion pore stability and expansion. Altogether, this work provides insight into the roles that subspecies of the same phospholipid may play based on their fatty acyl chain composition.

Although originally restricted to their structural role as major constituents of membranes, lipids are now well-defined actors to integrate intracellular or extracellular signals. Accordingly, it has been known for decades that lipids, especially those coming from diet, are important to maintain normal physiological functions and good health. This is especially the case to maintain proper cognitive functions and avoid neuronal degeneration. But besides this empiric knowledge, the exact molecular nature of lipids in cellular signaling, as well as their precise mode of action are only starting to emerge. The recent development of novel pharmacological, molecular, cellular and genetic tools to study lipids in vitroand in vivohas contributed to this improvement in our knowledge. Among these important lipids, phosphatidic acid (PA) plays a unique and central role in a great variety of cellular functions. This article will review the different findings illustrating the involvement of PA generated by phospholipase D (PLD) and diacylglycerol kinases (DGK) in the different steps of neuronal development and neurosecretion. We will also present lipidomic evidences indicating that different species of PA are synthesized during these two key neuronal phenomena.