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The volatility of crude oil markets and the pressing need for sustainable energy solutions have sparked significant interest in forecasting methodologies that can better capture market dynamics and incorporate environmentally responsible indicators. In this study, we address the gaps in the literature by proposing novel hybrid approaches based on combining wavelet decomposition with machine learning techniques (ANN-Wavelet and SVR-Wavelet) and advanced machine learning techniques (XGBoost and GBM) with advanced clean energy indicators to predict crude oil prices. These hybrid models significantly advance the field by reducing noise and improving result accuracy. Besides, these approaches were used to determine the best model for predicting crude oil market prices. Additionally, we employed the SHapely Additive exPlanations (SHAP) algorithm to analyze and interpret the models, enhancing transparency and explainability. Subsequently, we applied SHAP to investigate the predictive value of various asset classes, including the volatility index (VIX), precious metal markets (gold and silver), fuel markets (gasoline and natural gas), as well as green and renewable energy indices, about crude oil prices. The results reveal that the wavelet-SVR model demonstrates consistent and robust forecasting performance with low RMSE and MAPE values. Additionally, the GBM model emerges as highly accurate, yielding shallow forecasting errors. Conversely, the wavelet-ANN and XGBoost models exhibit mixed performance, showing effectiveness in the Full Sample but reduced accuracy during the Russia–Ukraine conflict. Notably, green and renewable energy markets, such as CGA and NextEra energy (NEE), emerge as significant predictors in forecasting crude oil prices. This research provides critical guidance amidst the Russia–Ukraine conflict in predicting oil prices by emphasizing the importance of incorporating environmentally responsible indicators into investment portfolios and policy choices. [ABSTRACT FROM AUTHOR]

Undoped, Fe, Sn doped and Fe/Sn co-doped copper oxides are prepared by precipitation synthesis. X-ray diffraction confirmed that the all synthesized powders show a monoclinic main CuO phase. The insertion of Fe or/and Sn within the CuO matrix moderately affects the preferential growth direction. Basically Fourier Transform Infrared (FTIR) confirmed about functional group and their vibrations in the CuO samples. The reflectance of the undoped sample is higher than that of the other samples. Compared to undoped CuO, the doped and co-doped NPs exhibit red-shifted gap energy. Indeed, the Fe-doped, and Sn-doped CuO NPs, exhibit a slight decrease of gap energy (1.47, 1.45 eV respectively) compared to the undoped CuO (1.49 eV), while the Fe/Sn co-doped sample has a lower gap energy of 1.06 eV. Additionally, the antibacterial efficiencies of the all-synthesized samples are tested against Staphyloccus species. Doped and undoped CuO nanopowders show important antibacterial activity on tested bacteria with MICs values ranged between 0.039 to 1.25 mg/ml. Minimum Inhibitory Concentration value of 0.039 mg/ml was obtained with Fe-doped CuO NPs (CuO:Fe NPs) against S.aureus ATCC33591, whereas the highest MIC value of 1.25 mg/ml was obtained with CuO:Sn nanopowder against the strain S. epidermidis, which was the most resistant strain. Moreover, all CuO NPs, except CuO:Fe/Sn showed important anti-adhesive and antibacterial activities against S. epidermidis when used as pellets. This was confirmed either by cell counts using the determination of CFU/ml of bacterial suspension inside the hole, or by using fluorescence microscopy. [ABSTRACT FROM AUTHOR]

Seven bacterial strains, isolated from various Tunisian biotopes, were investigated for Congo Red (CR) and Malachite Green (MG) decolorization. The isolated strains underwent morphological and biochemical tests, including assessments for antibiotic sensitivity as well as biofilm formation. One selected strain, ST11, was partially identified as Paenibacillus sp. strain ST11. The newly isolated crude bacterial filtrates (NICBFs) effectively decolorized CR and MG. Specifically, six and seven NICBFs were found to be effective for degrading CR (150 mg l−1) and MG (50 mg l−1), respectively. Under non-optimized conditions, CR and MG could be decolorized up to 80% within 6–12 h. The degradation products of CR and MG, characterized by UV–visible and FT-IR techniques, demonstrated both decolorization and transformation, highlighting the role of enzymes in dye degradation. Phytotoxicity and cytotoxicity studies evaluated the impact of treated and untreated CR and MG. Some NICBFs showed promise as powerful biological tools, reducing and sometimes detoxifying CR and MG, commonly used as fertilizers. The potential applications of these NICBFs in decolorization and bioremediation of dye-rich textile effluents were explored. The screening also identified environmentally friendly, cost-effective bacterial strains adaptable to various conditions through phytotoxicity and cytotoxicity studies. [ABSTRACT FROM AUTHOR]

The utmost aim of this study is the determination of the optimum ratio and the amount of almond gum (AL), sodium alginate (SA), and sodium caseinate (SC) in the formulation of tyrosol-nanoparticles. Indeed, the increase in the ratio of AL enhanced the encapsulation efficiency and significantly reduced the mean particle diameter (dp) of tyrosol-nanoparticles. Moreover, increasing the ratio of SC at an amount of 2.0% improved the polydispersity index of tyrosol nanodispersions. Besides, the high proportions of AL at the amount of 2.0% and SC at the amount of 1.0% enhanced the antioxidant activities of tyrosol nanoparticles. Hence, the statistical results showed that the mixture of 51.20% AL and 48.80% SC at the amount of 2.0% was proven to be the optimum condition which was confirmed in practice. Under these conditions, the experimental values of encapsulation efficiency, mean dp, polydispersity index, and antioxidant activity (IC50) were: 98.10%, 91.57 nm, 0.18, and 87.90 µM, respectively. Their molecular interaction was also confirmed by FTIR and thermal analysis which proved the encapsulation of tyrosol in an amorphous form. [ABSTRACT FROM AUTHOR]

Our objective in this paper is to show that, similarly to the case of normal operators, a normal linear relation on a Hilbert space H satisfies several notions related to the local spectral theory such as the single valued extension property (SVEP), Bishop and Dunford properties, and more generally the spectral decomposability. To that end, we shall start by introducing all those notions for a closed linear relation T on a Banach space X. Then, we will use an approach allowing us to establish that, as soon as a local spectral property holds for the orthogonal operator part of T, it will automatically hold for T. Finally, we will apply that approach on a normal linear relation to reach our objective. [ABSTRACT FROM AUTHOR]

In this paper, we aim to prove an index theorem for linear relations and apply it to study the invertibility and the essential invertibility of certain upper triangular block relation matrices. [ABSTRACT FROM AUTHOR]

The textile industry is a leading contributor to water pollution. Therefore, there is a need for economic and environmental efforts to manage the textile industry's wastewater. The present study used five bacterial strains, isolated from various Tunisian biotopes, to be characterized and screened for Congo Red (CR) decolorization, for the first time. Firstly, the isolated strains were subjected to standard cultural, microscopically, biochemical, antibiotic susceptibility and biofilm formation assays. The strain ST9 was partially identified as Bacillus spp. strain ST9. Secondly, the newly bacterial isolates crude filtrates were able to decolorize CR, generally recalcitrant to biodegradation due to its xenobiotic nature. Thus, only SM2 and ST9 strains prove their effectiveness for CR (150 mg L−1) total degradation. More than 5.5 mg L−1 h−1 of CR could be decolorized using ST9 filtrate under non-optimized conditions. UV–Visible and FT–IR analysis showed a decolorization and/or a transformation of CR, proving the role of the enzyme in dye decolorization. In fact, the azo dyes degradation was confirmed by the disparition of the characteristic peak at 499 nm and of the peaks located in the range 1610–1630 cm−1 and at 1600 cm−1 due to the azo bonds and the characteristic C=C band of the aromatic ring of CR, respectively. Combinning FTIR and UV–Vis spectra confirms the CR degradation using only SM2 and ST9 filtrates. The results showed CR has been degraded into nontoxic compounds evaluated by (1) phytotoxic assay on tomato, radish and watercress, and (2) cyto-toxicity assay in Vero cells. Furthermore, toxicity studies observed that the by-products from degradation by SM1 crude filtrate was not toxic to plants and less toxic to Vero cells as compared to pure CR. This work reported on the biodegradation of CR by bacterial crude filtrates, as green biocatalysts, which could be a potential candidate for the removal and detoxication of CR from textile wastewater. [ABSTRACT FROM AUTHOR]

Bacillus subtilis SPB1 derived biosurfactants (BioS) proved its bio-control activity against Agrobacterium tumefaciens using tomato plant. Almost 83% of disease symptoms triggered by Agrobacterium tumefaciens were reduced. Aiming potential application, we studied lipopeptide cost-effective production in both fermentations systems, namely the submerged fermentation (SmF) and the solid-state fermentation (SSF) as well as the use of Aleppo pine waste and confectionery effluent as cheap substrates. Optimization studies using Box–Behnken (BB) design followed by the analysis with response surface methodology were applied. When using an effluent/sea water ratio of 1, Aleppo pine waste of 14.08 g/L and an inoculum size of 0.2, a best production yield of 17.16 ± 0.91 mg/g was obtained for the SmF. While for the SSF, the best production yield of 27.59 ± 1.63 mg/g was achieved when the value of Aleppo pine waste, moisture, and inoculum size were, respectively, equal to 25 g, 75%, and 0.2. Hence, this work demonstrated the superiority of SSF over SmF. [ABSTRACT FROM AUTHOR]

In this paper, we develop the notion of spectral decomposability of a multi-valued linear operator (linear relation) in Banach spaces using subsets of the Riemann sphere C ∞. We are going to study several notions related to the extended local spectral theory of linear relations in C ∞ such as the extended relatively single-valued extension property ER-SVEP as well as the extended local and glocal spectral subspaces. More importantly, we explore these notions in order to establish sufficient conditions ensuring the spectral decomposability. [ABSTRACT FROM AUTHOR]

Detergent products are a formulated mixture of ingredients with a washing or cleaning power. The most active compounds involved in the cleaning process are the so-called surfactants; amphiphilic compounds with polar head and an-polar teal. They have the property to lower the surface tension (ST) of water, to adsorb to the interface and to reduce the interfacial tension (IFT) between two immiscible liquid. Then, they are very good at liberating dirt and to eliminate impurities. However, owing their chemical nature, they are characterized by their high toxicity and low biodegradability causing serious risks to natural ecosystems. Therefore, an urgent need was developed for the production of environment friendly detergent. Thus, developing eco-friendly, nonirritant, low-toxic, and high-efficient surface active ingredients for detergents is an ongoing challenge in the detergent field. To know, biosurfactants (BioS) or microbial surfactants are amphiphilic compounds having the ability to reduce the surface and interfacial tension. They are characterized by their higher biodegradability, low toxicity and eco-friendly. Thus, they can be the best substitutes of chemical surfactants in detergent formulation permitting the development of eco-friendly bio-based detergent formula. With this aim, we will discuss in the first part of the presented review detergent formula and surfactants as the base ingredients; their physic-chemical properties and higher toxicity. In the second part of the review paper, BioS as emerging ingredients for detergent formulation will be presented; their classification, physic-chemical and functional properties along with their potential application in detergent formulation. [ABSTRACT FROM AUTHOR]

In this paper, we study a system of second order integro-partial differential equations with interconnected obstacles with non-local terms, related to an optimal switching problem with the jump-diffusion model. Getting rid of the monotonicity condition on the generators with respect to the jump component, we construct a continuous viscosity solution which is unique in the class of functions with polynomial growth. In our study, the main tool is the associated of reflected backward stochastic differential equations with jumps with interconnected obstacles for which we show the existence of a unique Markovian solution. [ABSTRACT FROM AUTHOR]

Six clusters of Lipopeptides Isoforms belonging to Cyclic and Linear Surfactin and Fengycin A and B Families were identified from a newly identified strain identified as B. mojavensis BI2. Purification by anionic exchange chromatography and Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) and identification by High Performance Liquid Chromatography-Mass Spectroscopy (HPLC-MS) analyses were applied to characterize lipopeptides biosurfactants derived from B. mojavensis BI2. The m/z values of Cyclic and Linear homologues of Surfactin ranged from 980 and 1096 Da. The m/z values of cyclic homologues of Fengycin A and Fengycin B ranged from 1449 and 1505 Da. The m/z values of linear homologues of Fengycin A and Fengycin B ranged from 1467 and 1523 Da. Functional properties of the BI2 lipopeptides revealed a powerful surface activity with the capacity to decrease the surface tension of water to about 27.4 mN/m and a Critical Micelle Concentration (CMC) value of 200 mg/L along with great efficiency when compared to chemical surfactants (Triton X100; CTAB and SDS). Additionally, similarly to chemical surfactants, they exhibited similar foaming and oil dispersing activities. Interestingly, lipopeptides isoforms are characterized by non-phytotoxicity with potential fertilizing effect. All these functional properties offer potential application of these lipopeptides in bioremediation of contaminated water. [ABSTRACT FROM AUTHOR]

Biosurfactants stand for highly useful and promising compounds. They basically serve for a variety of applications in multiple industries and aspects of human life. Therefore, it is highly required to improve their production yield especially through the development of new and more efficient fermentation processes. In this aim, batch and fed-batch were studied and compared in terms of their effective biosurfactant production by Bacillus subtilis SPB1. Experiments of fed-batch fermentations were carried out through three different glucose feeding strategies, namely the pulsed, the constant Donespeed and the exponential feeding. The comparison between different fermentation processes revealed that fed-batch process proved to be a more efficient cultivation strategy than the batch process in terms of cell biomass, biosurfactant production and productivity. Among the three different feeding strategies, the exponential feeding process achieved the highest fermentation results of final biosurfactant concentration. The latter increased more than twofolds compared to batch fermentation. [ABSTRACT FROM AUTHOR]

A bounded linear relation T on a complex Banach space X is called a relatively regular linear relation, if T B T = T and T (0) ⊆ N (B) for some bounded operator B on X. This paper contains some properties, characterizations and decomposably results of relatively regular linear relation. [ABSTRACT FROM AUTHOR]

This study investigates the tensile properties of the PC/ABS blend under both small and large strains using experimental analysis and predictive analytical models. The influence of temperature and strain rate on the tensile response were evaluated, with strain rates reaching from 1.25 × 10−4 to 1.25 × 10−1 s−1 and temperatures ranging from 20 to 150 °C. The experimental results indicate that the tensile behavior of the material blend exhibits sensitivity to both strain rate and temperature. As the temperature rises, the yield strength and strain at failure decrease significantly; while, the young’s modulus only slightly decreases. Among several constitutive models studied, including the G’sell and Jonas and Duan–Saigal–Greif–Zimmerman (DSGZ) models, a modified version of the DSGZ model, referred to as the “Zhu et al.” model. However, this model struggled to accurately represent material behavior at elevated temperatures. To address this limitation, a new model named Hentati–Mnif–Hfaiedh–Petit (HMHP) was developed by introducing a temperature dependence into two key parameters of the “Zhu et al.” model. This improvement enabled the HMHP model to more accurately predict tensile behavior across a wide temperature range. The results confirm that the new developed model, HMHP provides a reliable prediction of tensile properties at different temperatures. [ABSTRACT FROM AUTHOR]

We prove that for any ring R of Krull dimension not greater than 1 and n ⩾ 3, the group En (R[X, X−1]) acts transitively on Umn(R[X, X−1]). In particular, we obtain that for any ring R with Krull dimension not greater than 1, all finitely generated stably free modules over R[X, X−1] are free. All the obtained results are proved constructively. [ABSTRACT FROM AUTHOR]

Leukemic cells proliferate faster than non-transformed counterparts. This requires them to change their metabolism to adapt to their high growth. This change can stress cells and facilitate recognition by immune cells such as cytotoxic lymphocytes, which express the activating receptor Natural Killer G2-D (NKG2D). The tumor suppressor gene p53 regulates cell metabolism, but its role in the expression of metabolism-induced ligands, and subsequent recognition by cytotoxic lymphocytes, is unknown. We show here that dichloroacetate (DCA), which induces oxidative phosphorylation (OXPHOS) in tumor cells, induces the expression of such ligands, e.g. MICA/B, ULBP1 and ICAM-I, by a wtp53-dependent mechanism. Mutant or null p53 have the opposite effect. Conversely, DCA sensitizes only wtp53-expressing cells to cytotoxic lymphocytes, i.e. cytotoxic T lymphocytes and NK cells. In xenograft in vivo models, DCA slows down the growth of tumors with low proliferation. Treatment with DCA, monoclonal antibodies and NK cells also decreased tumors with high proliferation. Treatment of patients with DCA, or a biosimilar drug, could be a clinical option to increase the effectiveness of CAR T cell or allogeneic NK cell therapies. [ABSTRACT FROM AUTHOR]

This paper initiates a study of upper and lower generalized Drazin invertible linear relations classes. We first aim to give a characterization of these classes via a generalized Kato decomposition. Then, we establish some characterizations of these classes in terms of an associated projection. Some issues of the local spectral theory of linear relations in Banach spaces are also thought of. Finally, we apply these results to deduce a new characterization of these classes by means of the analytic residuum concept. [ABSTRACT FROM AUTHOR]

Aiming the production of lipopeptides biosurfactants (BioS), we isolated a new strain identified as Bacillus subtilis ZNI5 from a hydrocarbon contaminated soil. Lipopeptides purification by anionic exchange chromatography and identification by Reverse Phase High Performance Liquid Chromatography–Mass Spectrometry (RP-HPLC–MS) permitted the selection of different homologues divided into four families. The first family corresponds to Surfactin isoforms with molecular weights of 1007, 1021 and 1035 Da; the second family correspond to Iturin isoforms with molecular weights of 1028, 1042 and 1056 Da; the third family correspond to a single isoform called Licheniformin with molecular weight of 1410 and the fourth family correspond to newly identified isoforms named Inesfactin with molecular weights of 973 and 987 Da. Regarding the functional properties of the ZNI5 BioS, it was characterized as a powerful surface-active agent that decreases the Surface Tension of water from 72 mN/m to about 32 mN/m with a CMC value of 350 mg/L more efficient than chemical surfactants (Triton X100; CTAB and SDS). Moreover, it has the capacity to disperse oil to about 80 mm at a concentration of 800 mg/L showing close efficiencies to the listed chemical surfactants. In addition, the physic–chemical characterization of the surface activities of ZNI5 BioS showed great thermal, pH and salts activity and stability enabling its use in the bioremediation fields and for diverse industrial applications. [ABSTRACT FROM AUTHOR]

Background: An association between ANXA1, FPR1 and FPR2 gene polymorphisms and the patho-physiology of many human diseases was suggested by numerous studies. Objective: Our study aimed to evaluate association between common polymorphisms in the 9q21.13 and 19q13.41 and susceptibility to systemic lupus erythematosus (SLE) in the Tunisian population. Materials: We performed a case–control study on 107 Tunisian SLE patients and 122 healthy controls to explore 9 polymorphisms of the three studied genes: rs2811226 and rs3739959 (ANXA1), rs5030880, rs1042229, rs1461765570, rs17849971, rs867228 (FPR1), rs17694990 and rs11666254 (FPR2). Results: Four polymorphisms were found to be linked with SLE susceptibility: rs3739959-ANXA1 > G and GG (p = 0.021, OR = 1.73 and p = 0.014, OR = 2.06 respectively), rs867228-FPR1 > TT (p = 0.014, OR = 4.59), rs11666254-FPR2 > GG (p = 0.019, OR = 8.34) and rs17694990-FPR2 > T (p = 0.05, OR = 1.506). In homogenous groups of SLE patients depending on clinical manifestations and serological results, previous associations were confirmed with a panoply of manifestations of lupus including lupus nephritis, malar rash, mouth ulceration and hypocomplementia. Conclusion: Our study showed an association between ANXA1 > rs3739959, FPR1 > rs867228, FPR2 > rs11666254, FPR2 > rs17694990 and SLE susceptibility. Our results also showed a strong association between the two ANXA1 studied SNPs and LN which allowed us to suggest these two SNPs as biomarkers of LN development in SLE. Further research is needed to understand by which mechanism the gene variants affect susceptibility to SLE. Key Points •Lupus erythematosus is an autoimmune disease in which a panoply of factors are implicated •Annexin A1 interaction with its receptors are suggested as a target in therapy of a panoply of human disease in particular cancers •The present results highlighted the implication of Annexin A1 and its receptors gene polymorphisms in the physiopathology of lupus, in particular in the involvement of renal and cutaneous lesions [ABSTRACT FROM AUTHOR]

The present study summarizes the valorization of date flour by the production of lipopeptide biosurfactant (BioS) by Bacillus subtilis ZNI5 (MW091416). A Taguchi design permitted the formulation of a medium composed only of 6% date flour and 0.5% yeast extract within 2 days of incubation at 150 rpm with a maximal surface tension (ST) reduction of about 27.8 mN/m. The characterization of the lipopeptide shows a CMC value of about 400 mg/L with a minimal ST of 30 mN/m and an ability to disperse oil to about 80 mm at 800 mg/L. Having reduced phytotoxicity, the ZNI5 BioS and ZNI5 strain were assayed for Copper and Cobalt chelation and biosorption. The improvement of the germination index of radish seeds irrigated by the treated contaminated water showed the great potential application of ZNI5 lipopeptide in the bioremediation of heavy metals. [ABSTRACT FROM AUTHOR]

This paper presents the design of an Ultra-Wide Band (UWB) Low Noise cascaded Amplifier (LNA) used for biomedical applications. The designed structure uses a technique which is based on the inductances minimization to reduce the LNA surface while maintaining low power consumption, low noise and high stability, linearity and gain. To prove its robustness, this technique was studied theoretically, optimized and validated through simulation using the CMOS 0.18 µm process. The LNA achieves a maximum band voltage gain of about 17.5 dB at [1-5] GHz frequency band, a minimum noise figure of 2 dB, IIP3 of + 1dBm and consumes only 13mW under a 2 V power supply. It is distinguished by its prominent figure of merit of 0.68. [ABSTRACT FROM AUTHOR]

Purpose: The use of complementary and alternative medicine (CAM) is common among breast cancer patients, but less is known about whether CAM influences breast cancer survival. The primary aim of this study was to determine the impact of self-use of herbs on the overall survival. Methods: This was a prospective study including 110 patients with breast cancer. All patients were questioned about the concept of taking herbs. We analyzed the demographic data and the overall survival. Results: The average age was 51 years (30–80 years old). 37 had metastatic disease (33.6%). 48 patients had taken plants (43.6%). 19 patients consumed Graviola (39.6%) and 29 Alenda (60.4%). Overall survival at 3 years and at 5 years were, respectively, 96.2% and 82.4% in the absence of plant consumption versus 78.5% and 78.5% in case of plant consumption (p = 0.015). Conclusion: This study concluded that self-medication with Graviola or Alenda may be associated with an increase of death risk in patients with breast cancer. Further studies are needed to confirm these results. [ABSTRACT FROM AUTHOR]

Lipopeptides biosurfactants (BioS) are natural surface-active compounds produced by a variety of microorganisms. They have great interest in environmental, biomedical and agro-industrial fields. However their large-scale application and production is limited by the cost of culture media and the low yield of production. Therefore, the improvement of the production yields and the development of efficient and cost-effective bioprocess became of a great interest. In this aim, we applied the response surface method to optimize an economic BioS production by a newly isolated strain Bacillus mojavensis BI2 on date Juice called "Luegmi" as unique carbon and nitrogen source. Using a Box-Bhenken design, we studied the effect of three independent variables on lipopeptide production; Leugmi concentration, Na2HPO4 and incubation time. The results of this study showed that Leugmi concentration at 25%, Na2HPO4 at 0.1% and incubation time of 24 h were optimal conditions for BioS production, with a maximum Surface Tension (ST) decreasing capacity of 55% corresponding to 27 mN/m and an Oil Dispersing Activity (ODA) of 30 cm2 corresponding to a diameter of 6 cm. Preliminary characterization of the BioS produced on Luegmi by UV-Spectra and Thin Layer Chromatography showed its lipopeptide nature. Physic-chemical characterization of the produced lipopeptide on Leugmi showed its great surface activities and stabilities at different pH, temperature and salts concentration. The results of this study suggested that Leugmi, an agricultural byproducts can be used as a low-cost substrate to enhance the yield of lipopeptide BioS with great surface activities for potential environmental application. [ABSTRACT FROM AUTHOR]

We initiate a study of local spectral theory for linear relations. At the beginning, we define the local spectrum and study its properties. Then we obtain results related to the correlation analytic core K′(T) and the quasinilpotent part H0(T) of a linear relation T in a Banach space X. As an application, we present a characterization of the surjective spectrum 𝜎su(T) in terms of the local spectrum and show that if X = H0(⋋I − T) + K′(⋋I − T), then 𝜎su(T) does not cluster at ⋋. [ABSTRACT FROM AUTHOR]

We sought to determine the relative value of conventional molecular methods and whole-genome sequencing (WGS) for subtyping Salmonella enterica serovar Enteritidis recovered from 2000 to 2015 in Tunisia and to investigate the genetic diversity of this serotype. A total of 175 Salmonella Enteritidis isolates were recovered from human, animal, and foodborne outbreak samples. Pulsed-field gel electrophoresis (PFGE), multiple locus variable-number tandem repeat analysis (MLVA), and whole-genome sequencing were performed. Eight pulsotypes were detected for all isolates with PFGE (DI = 0.518). Forty-five Salmonella Enteritidis isolates were selected for the MLVA and WGS techniques. Eighteen MLVA profiles were identified and classified into two major clusters (DI = 0.889). Core genome multilocus typing (cgMLST) analysis revealed 16 profiles (DI = 0.785). Whole-genome analysis indicated 660 single-nucleotide polymorphism (SNP) divergences dividing these isolates into 43 haplotypes (DI = 0.997). The phylogenetic tree supported the classification of Salmonella Enteritidis isolates into two distinct lineages subdivided into five clades and seven subclades. Pairwise SNP differences between the isolates ranged between 302 and 350. We observed about 311 SNP differences between the two foodborne outbreaks, while only less or equal to 4 SNP differences within each outbreak. SNP-based WGS typing showed an excellent discriminatory power comparing with the conventional methods such as PFGE and MLVA. Besides, we demonstrate the added value of WGS as a complementary subtyping method to discriminate outbreak from non-outbreak isolates belonging to common subtypes. It is important to continue the survey of Salmonella Enteritidis lineages in Tunisia using WGS. [ABSTRACT FROM AUTHOR]

This paper presents an original approach, using a harmonic balance optimization method, allowing to predict the maximum phase shift range that can be practically obtained for an array of N coupled oscillators. Indeed, unlike what is predicted by the theory, the proposed analysis allows to show that the maximum value of the phase shift decreases by increasing the number N of coupled oscillators in the array. Hence, this method allows to find an empirical limit of the phase shift obtained between two adjacent oscillators which tends to ± 180°/N. The results obtained with the proposed method are compared with the measurement results of an array made of two and four coupled voltage controlled oscillators (VCOs) implemented in the QUBiC4X 0.25 µm BiCMOS SiGe:C process of NXP semiconductors. These measurement results confirmed that the maximum measured phase shift range is close to ± 180°/2 and ± 180°/4 for arrays made of two and four coupled VCOs respectively. [ABSTRACT FROM AUTHOR]

This paper presents the design and the implementation of a fully integrated active phase shifter for beamforming at 5.8 GHz. The proposed circuit, implemented in a 0.25 µm BiCMOS SiGe:C process, is based on an original architecture using an injection-locked oscillator (ILO) associated with an in-phase/quadrature (IQ) modulator. The dynamic behaviour of an ILO is first analysed theoretically and important characteristics are deduced. At 2.5 V power supply voltage and total power dissipation of only 92.5 mW, the proposed circuit allows to obtain a 360° phase shift range and occupies 1.43 mm2. This phase shift is synthesised using the ILO for fine-tuning and the IQ modulator for coarse tuning. [ABSTRACT FROM AUTHOR]

With the increase of the usage of multimedia applications, the next generation of wireless networks need to satisfy the quality of the transmitted application even if the network is characterized by limited radio resources such as bandwidth (that it is not less than that required by all the traffic sessions). Many call admission control (CAC) and bandwidth degradation algorithms for real time transmissions were proposed. However, CAC algorithms may consume intensive processing time that can provoke delay constraint violation for new calls and handover calls, in particular when it deals with real-time transmission. All this could cause the degradation of the quality of service (QoS) requirements. To overcome this problem, our proposed algorithm aims to minimize the risk of delay violation by facilitating the triggering of the CAC algorithms. The objective is to adapt the available bandwidth of the wireless resources to be ready to admit any new session without degrading the QoS of already existing sessions. A bandwidth level degradation algorithm is presented to reduce the bandwidth of some active sessions in the cell in order to accommodate the arrived calls. Moreover, an upgrading bandwidth algorithm is also presented when a call is finished or passed to another cell to increase the bandwidth of residual calls having a risk of QoS degradation. New call blocking probability, handover call dropping probability and bandwidth utilization were used to evaluate the performance of our algorithm. Simulation results show that the proposed algorithm is efficient and it is advantageous to use it for a better management of radio resources. The blocking probability for new calls is about 10% which is significantly lower than of others studied algorithms and about 15% is shown for handover dropping ratio. Those result respond to the QoS requirements although 100% of bandwidth utilization. [ABSTRACT FROM AUTHOR]

In this paper, B-Fredholm linear relations in Hilbert spaces are introduced and some of their properties are given. In particular, it is shown that they are completely characterized in terms of an algebraic decomposition with a Fredholm linear relation and a bounded nilpotent operator. The behaviour of a polynomial in them is also investigated. [ABSTRACT FROM AUTHOR]

Lipases are hydrolytic enzymes owing much importance in industrial applications. These enzyme-based detergents are ecofriendly and produce a wastewater with low level of COD (chemical oxygen demand). In the present work, a novel halophilous, thermoalkaline, and detergent-tolerant lipase produced by a newly isolated Aeribacillus pallidus strain VP3 was studied. Considerable interest has been given to this lipase by the improvement of its catalytic activity through the optimization of the pH, the (C/N) ratio, and the inoculum size, using the response surface methodology based on the Box-Behnken design of experiments. A total of 16 experiments were conducted, and the optimized pH, (C/N) ratio, and inoculum size were 10, 1, and 0.3, respectively. The results of the analysis of variance (ANOVA) test indicated that the established model was significant (p value < 0.05). The optimization of the production conditions leads to 2.83-fold of increase in the catalytic activity calculated as the ratio of the activity obtained after optimization (68 U) and the initial activity before optimization (24 U). All in all, the lipase of Aeribacillus pallidus could be considered as a potential candidate to be incorporated in detergent formulations since it shows a good stability towards detergents and wash performance. [ABSTRACT FROM AUTHOR]

We characterize the isolated points of the spectrum, the poles of the resolvent and the Riesz points of a bounded and closed linear relation on a Banach space. The found results include and generalize some known characterizations in the frame of bounded operators. [ABSTRACT FROM AUTHOR]

Production of rock aggregates is an important industrial activity. Quality estimation of rock aggregates is often performed with standardized mechanical tests which are intended for testing the products, not the original rock material. In fact, conventional tests dealing with mechanical performance of aggregates (abrasion and fragmentation resistance) are laborious tasks. They are time consuming and require tough laboratory procedures. Thus, there is a need for an effective method to estimate the quality of rock aggregates in the early stages of quarry prospection. This work aims to present a non-destructive ultrasonic technique to characterize mechanical strength of carbonate rock aggregates, mainly defined with Los Angeles (L.A.) and Micro-Deval (M.D.E.) measurements. For experimentation, porosity, density, L.A., and M.D.E. coefficients were calculated for 11 carbonate rock samples. Beforehand, ultrasonic measurements were taken on rock samples using longitudinal P wave with a frequency of 55 kHz. Regression analysis indicated that L.A. and M.D.E. coefficients were linearly correlated with ultrasonic velocity. Similar results were shown for porosity and density. Artificial neural networking was performed to establish a predictive model linking porosity density and ultrasonic velocity to L.A. or M.D.E. measurements. For our knowledge, this is the first paper of a correlation between L.A. and M.D.E. coefficients with ultrasonic velocity. Results have indicated the ability of this technique to elaborate an accurate approach for prediction of mechanical performances determined with laborious experiments on rock aggregates. This paper adds to the knowledge about the wide effectiveness of ultrasonic techniques to predict the quality of aggregates and proves its efficacy in estimating their quality in the early stages of its production, in field and in time, which presents economical benefits for rock aggregate industries. [ABSTRACT FROM AUTHOR]

Objectives: The introduction of liraglutide in the treatment of patients with type 2 diabetes already taking insulin is still subject to discussion in terms of timing and benefits. Gradually intensive insulin therapy is hastily prescribed. Switching from multiple insulin injection (MII) to insulin and liraglutide is evaluated in this study. Methodology: We studied 92 patients with type 2 diabetes previously under MII, C-peptide ≥ 1.5 ng/ml, divided into a group with reasonable glycemic control [RC: HbA1c < 8% (64 mmol/mol)] and another with a poor control [PC: HbA1c ≥ 8%, (64 mmol/mol)] after introduction of liraglutide and insulin therapy. Results: Except for HbA1c, there were no statistical differences between RC and PC groups. Basal insulin doses were adjusted to achieve the fasting plasma glucose of 90–120 mg/dl. HbA1c was significantly improved in both groups, from 9.6% ± 1.6 (81 mmol/mol) and 7.0% ± 0.6 (53 mmol/mol) to 8.0% ± 1.5 (64 mmol/mol) and 6.8 ± 0.5% (51 mmol/mol). Reduction of body weight was significant only in RC (from 70 ± 16 kg to 68 ± 16 kg, p < 0.01). All patients from RC group and 58% of PC group reached HbA1c < 8% without hypoglycemia. Conclusion: This observation persuades us to propose the liraglutide and insulin combination to patients with C-peptide ≥ 1.5 ng/ml, regardless of the HbA1c. [ABSTRACT FROM AUTHOR]

We study a general robust utility maximization problem from terminal wealth and consumption under state constraints. Our framework includes financial models with constrained portfolios, labor income and large investor models. We state the existence and the uniqueness of the consumption–investment strategy by studying the associated quadratic backward stochastic differential equation. We characterize the optimal control by using the duality method and deriving a dynamic maximum principle. [ABSTRACT FROM AUTHOR]

Let T be a bounded linear relation (multivalued linear operator) in a Banach space X. We say that T is a Saphar type linear relation if its null space N(T) is contained in its generalized range ⋂ n = 1 ∞ T n (X) and if there is a bounded linear operator S such that T S T = T and T (0) ⊂ N (S) . In this paper we show that many characterization results of Saphar type operators remain valid in the context of multivalued linear operators. [ABSTRACT FROM AUTHOR]

The bacterial strain F4, isolated from olive oil-contaminated soil, has been found to produce biosurfactants as confirmed by oil displacement test and the emulsification index results. The identification of the strain F4, by 16S ribosomal RNA gene, showed a close similarity to Bacillus safensis, therefore the strain has been termed Bacillus safensis F4. The Thin Layer Chromatography (TLC) and the High Pressure Liquid Chromatography-Mass Spectrometry (HPLC–MS/MS) demonstrated that the biosurfactant had a lipopeptide structure and was classified as surfactin. The present study showed also that the produced biosurfactant has an important antibacterial activity against several pathogen strains as monitored with minimum inhibitory concentration (MIC) micro-assays. In particular, it presented an interesting anti-planktonic activity with a MIC of 6.25 mg mL−1 and anti-adhesive activity which exceeded 80% against the biofilm-forming Staphylococcus epidermidis S61 strain. Moreover, the produced lipopeptide showed an antitumor activity against T47D breast cancer cells and B16F10 mouse melanoma cells with IC50 of 0.66 mg mL−1 and 1.17 mg mL−1, respectively. Thus, our results demonstrated that Bacillus safensis F4 biosurfactant exhibited a polyvalent activity via a considerable antibiofilm and antitumoral potencies. [ABSTRACT FROM AUTHOR]

Purpose: Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic disorder mostly characterized by gonadotropins release and/or action deficiencies. Both isolated (idiopathic hypogonadotropic hypogonadism) and syndromic (Kallmann) forms are identified depending on the olfactory ability. Clinical and genetic heterogeneities of CHH have been widely explored, thus improving our understanding of the disease's pathophysiology. This work aims to (1) provide a detailed clinical and hormonal description of normosmic CHH patients and (2) identify the mutation linked to the studied phenotype. Participants and methods: We investigated three affected patients with normosmic CHH, belonging to a consanguineous Tunisian family. Patients underwent an insulin-induced hypoglycemia test. We performed whole exome sequencing to identify the causal mutation. Results: At first diagnosis, a total gonadotropic deficiency was identified in all patients. The insulin-induced hypoglycemia test has also revealed a reduced cortisol secretion and complete growth hormone deficiency. At 20.8 years, one female exhibited a spontaneous recovery of the hypothalamic–pituitary–adrenal axis function, unlike her affected siblings who still depend on corticosteroid replacement therapy. Herein, we identified a novel homozygous nonstop mutation (c.1195T>C) in KISS1R gene in all affected subjects. This mutation led to the substitution of the physiologic stop codon by an arginine (p.X399R). Conclusions: Our study highlights the importance of the KISS1R signaling, in gonadotropin-releasing hormone neurons, in the control of reproductive function. Additionally, our data suggests a complex central and peripheral metabolic control of puberty, through the hypothalamic KISS1R signaling. We suggest a mutual link between the hypothalamic–pituitary–gonadal, –adrenal, and –somatotropic axes. [ABSTRACT FROM AUTHOR]

In this paper, the notion of Drazin invertibility in the case of multivalued operators is introduced. Many results from operator theory are covered. Applications of some obtained results allow to study the Drazin invertibility of a multivalued operator matrix M C : = A C 0 B acting in the product of Banach or Hilbert spaces X × Y . [ABSTRACT FROM AUTHOR]

This article examines the link between technological changes and employment. The objective of this work is to determine the impact of technological innovations in the short and long term. In all the developed countries, the unemployed are rather low-skilled whereas highly skilled employees face less unemployment problems. Several studies have shown that technical progress leads to the casualization of non-skilled labor and to unemployment. This idea is based on the substitution of capital at work. Moreover, technical progress requires a skilled workforce capable of creating, innovating, and controlling further progress. Thus, technological innovations are not neutral; there are skill-biased technological changes. However, according to the theory of compensation, technological innovations reduce short-term employment (replacement effect) but create it in the medium and long term (compensation effect). The empirical validation of this work is based on the technique of structural VECM for the case of Tunisia. Unlike the theory of compensation, our results support the fact that the short-term effect of technological innovations on employment is positive; however, in the medium and long term, it is negative. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the perception of body image by Tunisian women and their spouses and to examine its impact on female sexuality. Our study involved 300 Tunisian women who had been married for at least 1 year and consulted in primary care medicine during the months of June and July 2016. Each participant completed a questionnaire covering four areas: women’s perception of their body, the perception of the spouses of the latter as it was reported by the participants, sexual activity, and the impact of body perception on sexual activity. The participants were satisfied with their bodies in 51% of cases. This satisfaction was associated with perceiving the body as physically attractive (p = 0.007), young (p = 0.047) and as a source of confidence (p < 0.001). Compared to women dissatisfied with their bodies, those satisfied declared satisfaction of sexual desire (p = 0.005), reaching orgasm (p = 0.001), taking the initiative in sexual activity (p = 0.003) and preparation for sex (p = 0.006). Perceived satisfaction of the partner with the female body was related to a more positive sexuality in women, specifically to women’s sexual satisfaction (p = 0.018), women taking sexual initiative (p = 0.014) and preparation for sex (p = 0.001). Our study indicates the important impact of a positive perception of the body image of Tunisian women by themselves and by their spouses on their sexuality. It would be interesting to consider these aspects in the management of female sexual disorders. [ABSTRACT FROM AUTHOR]

This paper discusses the ability of ultrasonic wave velocity to evaluate some physical parameters within mortar. The behavior of ultrasonic pulse velocity within mortar subjected to incremetal stress was also studied. For experimentation, we carried out ultrasonic measurements on mortar samples before and during uniaxial compressive strength, perpendicularly to the stress direction. The water/cement ratios were varied in order to contribute certain specific characteristics. A set of expressions was obtained linking the initial velocities of longitudinal ultrasonic waves with compressive strength, density, porosity and load at elastic limit.The evolution of ultrasonic velocity through mortar samples under continuous incremental uniaxial stress were also investigated. The results illustrated the behavior of ultrasonic pulse velocity as a function of the applied stress. It was observed that velocity did not decrease under initial loading and until about 70% of the ultimate stress, where sudden decrease occurred, followed by the failure of the material. [ABSTRACT FROM AUTHOR]

It is widely accepted that the estimation of biological attributes in the human skeleton is more accurate when population-specific standards are applied. With the shortage of such data for contemporary North African populations, it is duly required to establish population-specific standards. We present here the first craniometric standards for sex determination of a contemporary Tunisian population. The aim of this study was to analyze the correlation between sex and metric parameters of the skull in this population using CT scan analysis and to generate proper reliable standards for sex determination of a complete or fragmented skull. The study sample comprised cranial multislice computed tomography scans of 510 individuals equally distributed by sex. ASIRTM software in a General ElectricTM workstation was used to position 37 landmarks along the volume-rendered images and the multiplanar slices, defining 27 inter-landmark distances. Frontal and parietal bone thickness was also measured for each case. The data were analyzed using basic descriptive statistics and logistic regression with cross-validation of classification results. All of the measurements were sexually dimorphic with male values being higher than female values. A nine-variable model achieved the maximum classification accuracy of 90% with −2.9% sex bias and a six-variable model yielded 85.9% sexing accuracy with −0.97% sex bias. We conclude that the skull is highly dimorphic and represents a reliable bone for sex determination in contemporary Tunisian individuals. [ABSTRACT FROM AUTHOR]

Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. Glycolipids are characterized by highly structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface respectively. It presented initially a detailed classification of glycolipid including rhamnolipids, trehalolipids, mannosylerythritol-lipids, cellobiolipids; along with their producing strain. The review described the main functional properties of glycolipid including emulsification/de-emulsification capacity, foaming and moisturizing, viscosity reduction and hydrocarbon solubilizing and mobilizing capacities. Owing these properties, they can be applied in environmental fields as hydrocarbon emulsifiers, solubilizing and mobilizing agents, for their moisturizing capabilities and ability to reduce viscosity. The review will present a detailed classification of glycolipid biosurfactants, functional properties and the potential related applications in environment and bioremediation. [ABSTRACT FROM AUTHOR]

Electrodialysis is an electro-membrane process for desalination, concentration, and separation in electric fields. In this process, the operating currents are limited by the concentration polarization phenomena and the limiting current density. Usually, this parameter depends on membrane and solution properties as well as on the electrodialysis stack construction. In this research paper, we will apply the Box-Behnken design in combination with response surface methodology to the development of a predictive limiting current density model. We will also study the effects of three variables related to solution composition (calcium, sulfate, and bicarbonate concentrations) on this parameter. [ABSTRACT FROM AUTHOR]