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Thanks to their multifunctional properties, such as foaming, emulsifying and skin hydrating activities biosurfactants are potentially used in the cosmetic industry. In the present work, firstly, skin cream formulations using chemical surfactant agents and lipopeptide biosurfactants isolated from Bacillus subtilis SPB1 were investigated. The efficiency of the selected formula, containing 15% biosurfactant, was tested and its physicochemical properties were satisfying. In fact, it shows a spreading ability of 23 mm, a water activity of 0.72 and a pH value of 5. In addition, its biological activities were interesting showing a zone of inhibition against Gram-positive bacteria ranging from 8 to 15 mm. Moreover, it presents an antiradical effect against diphenyl-1-picrylhydrazyl (DPPH) with an IC50 of the order of 68 mg/mL. Second, seeking a highly stable SPB1 biosurfactant formulation for an easy commercial trend, a combination of biosurfactant, Gum Arabic (GA) and glycerol was optimized using the Box–Behnken (BB) design. As analysed, the model predicts an optimal value of the surface tension (ST) equal to 40.18 ± 0.39 mN/m when the respective values of the percentages of SPB1 BioS, glycerol and GA are equal to 72.62, 7.5 and 1.5%. Under these conditions, the emulsification index (EI)-24% is around 81.76 ± 0.14%.

The detection and quantification of Indole -3 Acetic Acid (IAA) produced by Plant growth promoting rhizobacteria (PGPR) rely on a standard well-documented assay, which remains time-consuming, laborious, and costly. These drawbacks led to sway interest to economic and reliable assays. The aim of this work is to validate and standardize a fast, reliable, and cost-effective microassay to quantify IAA produced by bacteria with an easy microplate method. In order to validate the accuracy of the IAA microplate assay, bacterial samples from different genera were assayed using two methods: the conventional IAA estimation assay and the IAA micro- assay. The microassay shows a prominent reduction in used bacterial supernatant volume as well as Salkowski reagent volume of about 92.5%. It is considerably cheaper than the conventional one of around 56%. The newly performed microplate assay is 23 times faster. The result of IAA quantitative analysis for 13 bacterial strains showed that Bacillus muralis and Bacillus toyonensis produced the highest IAA concentration (23.64±0.003μg/ml and 23.35±0.006μg/ml, respectively). The obtained data from both methods were highly correlated with an R-value of 0.979. The microassay offers the ability to read the optical density of all samples simultaneously since used volumes of bacterial supernatants and Salkowski reagent were minimized to place the mixture in 96-well microplates, which reduces greatly required labor. Furthermore, the application of the IAA micro-plate assay reduces drastically the reagent waste and toxicity hazard of Salkowski reagent in the environment, thus, we can classify it as eco-friendly respecting the Green Chemistry concept according to Environmental Protection Agency (EPA). The IAA microassay is a, reliable, rapid and cost-effective and eco-friendly method to screen plant growth promoting potential of more than 23 bacterial strains by microplate. It could be an alternative for the conventional IAA assay as a routine research tool.

The current work aims to optimize biological textile effluent treatment through the use of newly selected bacterial consortia composed of two strains: Citrobacter sedlakii RI11 and Aeromonas veronii GRI. We assessed the effect of SPB1 biosurfactant addition on color removal (CR). The process was optimized by a Box–Bhenken by examining the effect of pH, consortia density and biosurfactant value on treatment efficiency. Firstly, physicochemical analyses of the studied effluent revealed an alkaline pH along with a high content of suspended materials and large amounts of organic matter. Optimal CR and a chemical oxygen demand abatement of about 94 and 86% were obtained when treating the textile effluent at pH 5 with a total optical density of 0.4 and by incorporating 0.01% SPB1 biosurfactant. Additionally, an abolishment of phytotoxicity was registered after treatment optimization. The evaluations of the action mode of both selected bacteria during textile effluent treatment suggested the occurrence of biodegradation phenomena of dyes through enzymatic activities.

Aiming the potential application of lipopeptide biosurfactant (BioS) in bioremediation, we studied its production by a novel, isolated strain of Bacillus sp. MI27. Using the experimental design methodology, a novel medium composed of 2% sucrose, 0.27% Na2HPO4, 0.2% ammonium sulfate, 0.02% NaCl, 0.02% CaCl2, 0.02% MgSO4, 0.001% MnSO4, 0.06% KH2PO4, 0.005% FeSO4 and 0.005% ZnSO4 was optimized. With this composition, strain MI27 produces 1.4 g/L BioS with maximum surface tension (ST) reduction of 23 mN/m and a dispersion diameter of around 10 cm. Emulsifying and foaming activities have been also confirmed. The critical micelle concentration (CMC) value was about 120 mg/L with corresponding ST of 23 mN/m. The dispersion and emulsification index (EI) were about 12 cm and 45% at 1,000 mg/L respectively. Moreover, the foaming capacity, stable over 1 h of incubation, was about 80% at 1,000 mg/L. Additionally, we studied the effect of different pH, temperature and salinities on MI27 BioS activity and stability. Obtained results showed interesting surface activities at extreme physicochemical conditions, especially at acidic and alkaline pH values, high and low temperatures and higher salinities. All these characteristics enable the possible application of BioS in water treatment biotechnology under diverse environmental conditions.

Summary A 55-year-old patient was admitted to our department for the management of a repetitive alteration of consciousness. Biological investigation results were consistent with endogenous hyperinsulinemic hypoglycemia. Insulinoma was therefore suspected. Abdominal computed tomography and endoscopic ultrasound showed no obvious pancreatic mass.Somatostatin receptor scintigraphy showed abnormal radioactive uptake in both the pancreatic tail and the uncinate process. Contrariwise, abdominal magnetic resonance imaging showed a unique lesion in the pancreas tail. The patient was then proposed for pancreatic surgery. Both intraoperative manual palpation and intraoperative ultrasonography of the pancreas showed a single corporal lesion of 1.5 cm. No lesion was found in the uncinate process. After a left pancreatectomy, the lesion was histopathologically confirmed to be a well-differentiated neuroendocrine tumor. The symptoms of the patient resolved almost immediately following the surgery. The follow-up is one and a half years to date. Learning points The exact preoperative localization of the pancreatic mass remains the most challenging part of insulinoma diagnostic workup. The radiologist’s experience is the best warrantor to a precise localization of the tumor. 111In-DTPA-octreotide uptake in the pancreatic uncinate process may be physiological and its interpretation must, therefore, be vigilant. Manual palpation along with intraoperative ultrasonography is considered as the most effective method for the localization of insulinomas during open surgery.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE; OMIM 603041) is a rare inherited metabolic disorder mostly caused by mutations in TYMP gene encoding thymidine phosphorylase (TP) protein that affects the mitochondrial nucleotide metabolism. TP, functionally active as a homodimer, is involved in the salvage pathway of pyrimidine nucleosides. MNGIE-like syndrome having an overlapping phenotype of MNGIE was also described and has been associated with mutations in POLG and RRM2B genes. In the present study, we report the molecular investigation of a consanguineous family including two patients with clinical features suggestive of MNGIE syndrome. Bioinformatics analyses were carried out in addition to mtDNA deletion screening and copy number quantification in the blood of the two patients. Whole exome sequencing and Sanger sequencing analyses revealed the segregation in the affected family a novel mutation c.1205TA (p.L402Q) within the exon 9 of the TYMP gene. In addition, mtDNA analysis revealed the absence of mtDNA deletions and a decrease of the copy number in the blood of the two patients of the studied family. The p.Leu402Gln mutation was located in a conserved amino acid within the α/β domain of the TP protein and several software supported its pathogenicity. In addition, and based on docking and molecular dynamic simulation analyses, results revealed that L402Q caused a conformational change in TP mutated structure and could therefore alter its flexibility and stability. These changes prevent also the formation of stable homodimer leading to non-functional protein with partial or complete loss of its catalytic activity.

In the case of linear operator the property P(B, k) was introduced by M.A. Kaashoek. In this paper, we characterize the essentially semi regular linear relation in terms of the property P(B, k). After that and as an application of this result we give some connection between essentially semi regular and semi regular linear relations. Further, we will give some supplementary conditions on essentially semi regular linear relation to be semi Fredholm. Then, we analyze the stability of the class of essentially semi regular linear relations under small perturbations and Riesz operators. Finally, we study some properties of the essentially semi regular spectrum of a linear relation and we establish a spectral mapping theorem.

PurposeThe mining process is essential in cryptocurrency networks. However, it consumes considerable electrical energy, which is undoubtedly harmful to the environment. In response, energy-conserving cryptocurrency projects with reduced energy requirements or based on renewable energies have been developed. Recently, the COVID-19 pandemic and the Russian invasion of Ukraine ignited an unprecedented upheaval in financial products, especially in cryptocurrency and energy markets. Therefore, the paper aims to explore the response of these energy-conserving cryptocurrencies to the COVID-19 pandemic and the Russia–Ukraine conflict.Design/methodology/approachThis paper investigates the response of these energy-conserving cryptocurrencies to the COVID-19 pandemic and the Russia–Ukraine conflict. Their competitiveness is compared with conventional ones by analyzing their efficiency through multifractal detrended fluctuation analysis and automatic variance ratio during the COVID-19 and Russian invasion periods.FindingsThe empirical results show that all investigated energy-conserving cryptocurrencies negatively responded to the pandemic and positively reacted to the Russian invasion. On the other hand, all conventional cryptocurrencies reacted negatively to the COVID-19 pandemic and the amid-Russian attack. Besides, Bitcoin and SolarCoin were the least inefficient before the outbreak of COVID-19. Nevertheless, the Ethereum market became the most efficient after the pandemic spread. Similarly, the efficiency of Ripple was the most significant during the conflict between Russia and Ukraine. The energy crisis caused by Russia benefited the efficiency of the studied energy-conserving cryptocurrencies.Practical implicationsThis research is of interest to investors seeking opportunities in these energy-conserving cryptocurrencies and policymakers working to implement reforms to improve their market efficiency and promote long-term financial market growth.Originality/valueTo the best of the authors' knowledge, the behavior of cryptocurrencies based on renewable and reduced energy during the recent conflict between Russia and Ukraine has not been explored.

In this work, we evaluate the ability of a novel isolated bacteria identified as Bacillus thuringiensis RI16 (KM111604) to decolorize methyl red. Results showed its efficiency for the treatment of azo-dye-contaminated wastewaters under static conditions at pH values ranging from 7 to 9. The isolated bacteria could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/L. For better methyl red decolorization, we evaluate the potential use of Bacillus subtilis SPB1-derived lipopeptide biosurfactant. The study showed its ability to accelerate the decolorization rate and slightly maximized the decolorization efficiency at an optimal concentration of 0.025%. Compared with synthetic surfactants, the bacterial surfactant was more efficient as we observe a drastic decrease and an inhibition of methyl red decolorization by cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) additions. Also, studies ensured that methyl red removal by this strain could be due to extracellular enzymatic activities. SPB1 biosurfactant could improve enzyme activities and/or enzyme synthesis and diffusion.

Langerhans Cell Histiocytosis (LCH) is a rare clinical condition of the mononuclear phagocyte system caused by abnormal clonal proliferation of aberrant histiocytes or Langerhans cells . We describe this by reporting a case of a 28-year-old male patient presenting multi-system LCH with pituitary and bone involvement.

Olive by-products consisting of 40 % wood pruning and leaves, 40 % Olive pomace and 20 % OMW were ground and combined with preserving them by anaerobic fermentation (wet silage) for 4 months. The pH and total nitrogen/dry matter silage sample were 5.46 and 45 mg/g, respectively; the values comply with standards norms. After the silage process, a decreasing of phenol compound concentration of 67.85% was revealed and among 37 fatty acids compounds were identified with a valuable richness in mineralnutrients. The silage was devoid of total coliforms and fecal coliforms and yeast number doesn't exceed 489.95104 by gram of the silage. Correlation studies were done between the Silage and silage by-products parameters to evaluate the fermentation silage process. They showed different significant trends. A social-economic challenge was studied and discussed. Compared to that of using barley, the cost was 3 times less, with better quality for silage.

PurposeThe potential growth in cryptocurrencies has raised serious ethical and religious issues leading to a new investment rethinking. This paper aims to identify the influence of religiosity on cryptocurrency acceptance through an extended technology acceptance model (TAM) model.Design/methodology/approachIn the first phase, this research develops a conceptual model that extends the theory of the TAM by integrating the religiosity component. In the second phase, the proposed model is tested using search volume queries in daily frequencies from 01/01/2018 to 31/12/2022 and structural equation modeling (SEM).FindingsThe empirical results demonstrate a significant positive effect of religiosity on the intention to use cryptocurrency, the users' perceived usefulness (PU) and ease of use (PEOU). Besides, the authors note that PEOU positively influences the intention. Furthermore, religiosity indirectly affects the intention through the PEOU and positively impacts the intention through the PU. In the same way, PEOU has a considerable indirect effect on the intention through PU.Practical implicationsThis study has practical and theoretical contributions by providing insights into the cryptocurrency acceptance factors. In other words, it contributes to the literature by extending TAM models. Practically, it helps managers determine factors affecting the intention to use cryptocurrencies. Therefore, they can adjust their industry according to the suitable characteristics for creating successful projects.Social implicationsIdentifying the effect of religiosity on cryptocurrency users' choices and decisions has a social added value as it provides an understanding of the evolution of psychological variants.Originality/valueThe findings emphasize the importance of integrating big data to analyze users' attitudes. Besides, most studies on cryptocurrency acceptance are investigated based on one kind of religion, such as Christianity or Islam. Nevertheless, this paper integrates the effect of five types of faith on the users' intentions.