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SUMMARY OBJECTIVE: Beta-lactams resistance is a major clinical problem in treating pneumonia. This study aimed to detect the extended-spectrum beta-lactamases (ESBL) genes in Klebsiella pneumoniae among patients with community-acquired pneumonia (CAP) in Al-Najaf City, Iraq. METHODS: A total of 511 sputum samples were obtained from all suspected patients with CAP in Al-Najaf City, Iraq, from March 2020 to September 2020. Sputum samples were subjected to microbiological tests. The disk diffusion method was used to test antibiotic sensitivity. Production of ESBLs was identified using phenotypic and genotypic methods. RESULTS: The total prevalence of K. pneumoniae was 31.9% (163/511). Using CHROM agar, 41 (25.2%) isolates were ESBL producers. The imipenem 0.0% (n=0/41) and norfloxacin 0.0% (n=0/41) were the most effective antibiotics. The multiplex polymerase chain reaction showed that 46.3% (n=19/41) of isolates harbored ESBL genes. Out of 19 ESBL producers, 47.4% and 15.8% harbored blaCTX-M and blaSHV, respectively. While blaCTX-M and blaSHV genes were detected in 7 (36.8%) isolates, simultaneously. CONCLUSIONS: The imipenem and norfloxacin can be used in empirical treatment of K. pneumoniae isolates in Iraq. The emergence of K. pneumoniae strains harboring ESBL resistance genes necessitates the development of a regular surveillance program to prevent the spreading of these isolates more in Iraqi health care systems.

Camel meat is widely consumed in the Bechar region which happens to be warm to hot, exceeding 50°C in summer; fact that probably affects its physicochemical and microbiological quality. This study aimed to assess the camel meat production chain upstream. A primary HACCP (Hazard Analysis and Critical Control Points) study was conducted to detect the hazards, that were all related to the cold chain and refrigeration was the only mean used to preserve camel meat before marketing it raw. The kinetics of the physicochemical (temperature, pH, Total Dry Extract and humidity) and of the microbiological (Total Aerobic Mesophilic Flora, Coliforms, Staphylococci, Salmonella sp, Listeria monocytogenes, Pseudomonas sp, yeast and molds) parameters were then analyzed before and during cold storages, to study their limit over time. The results obtained showed that a temperature above the refrigeration temperature (+4 and +6°C) is likely to accelerate the microbial activity and to make the product unfit for consumption, a deterioration which resulted in a decrease in the rate of total dry extract (TDE) where the higher the temperature, the greater the loss of TDE, an alkalinization following proteolysis reactions with an increase in the humidity of the product. This study proved that the camel meat can meet national legislation for two weeks of storage at a temperature of up to 10°C. The evolution of the microbial and physicochemical parameters depends on several factors that should be strictly monitored, in particular the hygienic quality of the raw material, its handling and its storage conditions.

The current study focuses on the phytochemical characterization and biological activity of phenolic compounds derived from leaves of Moringa oleifera Lam. (Moringaceae) in the Tabelbala area (Bechar, Algeria). For a concentration of 1 mg/ml, the antioxidant tests revealed that the different extracts have a good reducing activity, with the tannin extract having the highest percentage of free radical inhibition (DPPH: 94%) compared to the n-butanolic extract (92%) and the ethyl acetate extract (88%). Furthermore, the tannin extract and the n-butanolic fraction of the flavonoids of the examined leaves showed significant antioxidant activity compared to ascorbic acid used as a reference (IC50 = 0.05 ± 0.14 mg/ml), with IC50 values of 0.07 ± 0.79 mg/ml for tannins and 0.0823 ± 0.25 mg/ml for the n-butanolic extract. In addition, the ferric reduction antioxidant power (FRAP) test reveals that all the tested extracts have a significant reduction power. The different selective extracts showed strong antimicrobial activity against nine pathogenic microbial strains: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Klebsiella pneumoniae (ATCC 13883), Citrobacter freundii (ATCC 29212), Acinetobacter baumannii (ATCC 19606), Bacillus cereus (ATCC 11778), Staphylococcus aureus (ATCC 25923), Enterococus faecalis (ATCC 13045), and Candida albicans, where the ethyl acetate fraction has a higher antibacterial activity than n-butanolic and tannin extract, with the zone of inhibition diameters ranging from 11 to 23 mm and have minimum inhibitory concentrations (MIC) between 0.39 and 3.125 mg/ml. These findings give scientific support for the plant’s traditional use, highlighting the value of traditional medicines in the treatment of many diseases.

Background:n recent years, multidrug resistance to antimicrobial agents, including antibiotics, has constantly been evolving, despite the diversity of these agents. However, such factors as the undesirable side-effects they cause, and sometimes the relatively expensive treatment costs, adaptation and new resistance mechanisms of microorganisms that emerged and spread globally, led many people to use bioactive compounds for treatment in the form of plant extracts known for their antimicrobial properties. The world health organization statistics estimate that medicinal plants, as basic drugs, are used by two-thirds of the world's population. Recent studies have focused on finding plants around the world with the appropriate and effective extract to be used as antimicrobial drugs. Fenugreek (Trigonella foenum-graecum L.) is an annual herb that is widely consumed globally as food, feed additive, and in herbal medicines as traditional remedies. Taking this into account, the present work aimed to study the phytoconstituents and in vitro antimicrobial activity of fenugreek seeds cultivated in Taghit region (Southwest of Algeria) against some uropathogenic bacterial strains.Methods:Qualitative tri phytochemical screening was carried out according to a standard protocol, based on staining and/or precipitation reactions, while the antibacterial test of two aqueous extracts and flavonoid, as selective extracts (n-butanolic and ethyl acetate fractions), was carried out by agar well diffusion method against a selection of Gram-positive and Gram-negative uropathogenic bacteria.Results:The obtained results showed a composition rich in phytoconstituents, especially in polyphenol, from where does probably comes the antibacterial effect that was ranging switched from low to strong effect on the majority of the tested strains with a stronger action attributed to flavonoid extracts compared to moderate effect of aqueous extracts. These results are linked not only to the extracts’ nature but also to the antibiotic resistance that was observed in the testing results for the isolated and reference bacterial strains where the isolated uropathogenic strains were multidrug- resistant against more than three classes of antibiotics, mainly: aminopenicillins, cephalosporins, 1st generation quinolones and also many others, such as Escherichia coli, Klebsiella spp, and P. aeruginosa species while most Staphylococcus sp strains were resistant to penicillin, tetracycline, and cotrimoxazole.Conclusion:However, flavonoids showed a greater effect compared to the antimicrobial activity of gentamicin, where Gram-positive uropathogenic isolates were more susceptible, with an activity index (AI) of 1 to 2.5 for S. aureus strains at concentrations of 27 to 223mg/mL. However, Gramnegative reference bacterial strains showed an activity index of 1 to 1.21 for E. coli, Citrobacter freundii, and Pseudomonas aeruginosa strains.

Background: The emergence of multidrug-resistant uropathogenic strains, mainly the global spread of extended-spectrum beta-lactamase (ESBL) genes accompanied both by the uncontrolled use of antibacterial agents and a considerable decrease in their activities, makes the monitoring of the resistance pattern one of the necessary means that could help the medical practitioners to choose the best treatment. For this purpose and during four months from March 1 to June 30 (2019), an experimental study has been carried out on urine specimens of 123 inpatients (IP) and outpatients (OP) at infectious disease service Boudjemaa TOURABI Public Hospital of Bechar (Algeria), aiming the detection of ESBL-producing Enterobacteriaceae uropathogenic strains. Methods: Firstly, the antibiotic susceptibility testing has been carried out by using the disk diffusion method to determine not only the multidrug resistance patterns, but also the multiple antibiotic resistance MAR indexes of uropathogenic strains that were isolated from clinical IP and OP samples. Secondly, the ESBL detection was done using the following methods: synergy tests based on the synergy between a third-generation cephalosporin and clavulanate, double-disc synergy test (DDST) and phenotypic tests on a cloxacillin-containing agar. Results: As a result, 56 patients had a urinary tract infection (UTI) in overall 123 patients; thus, a frequency of 45,52%. Through a UTI’s frequency of 64,7%, the female gender was the most affected. All age groups were affected by UTI, with a mean age of 38,47±19,97 years old. Knowing that UTIs’ patients aging from 16 to 49 years old were the most affected compared to other ages’ groups, with a frequency of 66,6 and 50% for female and male gender, respectively. The microbial strains represented by the bacteria group were predominant, i.e. (98,22%) followed by yeasts (1,78%), where Gramnegative bacilli showed (96,36%) of the uropathogenic agents, so (3,64%) were Gram-positive bacteria. The antibiotic resistance profile of isolated Enterobacteriaceae showed very high resistance rates for the species of Escherichia coli, Klebsiella spp, and Proteus spp to aminopenicillins, cephalosporins, and less against carbapenems and other drug groups. E. coli had presented the highest multidrug resistance followed by Klebsiella spp with a MAR index ranged from 0,53 to 0,82. Within this range, a total of 28 isolate (25 E. coli, 2 Klebsiella spp, and 1 Proteus mirabilis) had shown resistance against 9 to 14 out of the 17 tested antibiotics. The rate of ESBL-producing Enterobacteriaceae strains was 23,07 and 55,26% for inpatients and outpatients, respectively, where E. coli was the most important ESBL producers out of all isolated strains. Conclusion: An alarming ESBLs rate for outpatients is usually higher among inpatients with UTI, who receive several classes of antibiotics. Such conditions should be considered as a major public health concern, and measures must be taken to establish the sources and drivers of this issue. Thus, the findings of this research push the health sector stakeholders as well as the scientific communities to act on reducing the transmission of the multidrug-resistant strains that threaten several classes of life-saving antibiotics.

International audience; In this work, we have studied the pH-dependent surface charge nature of nanoporous graphene. This has been investigated by membrane potential and by streaming current measurements, both with varying pH. We observed a lowering of the membrane potential with decreasing pH for a fixed concentration gradient of potassium chloride (KCl) in the Donnan dominated regime. Interestingly, the potential reverses its sign close to pH 4. The fitted value of effective fixed ion concentration (C̅R) in the membrane also follows the same trend. The streaming current measurements show a similar trend with sign reversal around pH 4.2. The zeta potential data from the streaming current measurement is further analyzed using a 1-pK model. The model is used to determine a representative pK (acid–base equilibrium constant) of 4.2 for the surface of these perforated graphene membranes. In addition, we have also theoretically investigated the effect of the PET support in our membrane potential measurement using numerical simulations. Our results indicate that the concentration drop inside the PET support can be a major contributor (up to 85%) for a significant deviation of the membrane potential from the ideal Nernst potential.

Background: Algeria, by its vast terrestrial extent and its climatic variation, has an abundant, rich and varied flora in which it was counted many aromatic and medicinal species that provide bioactive compounds characterized by their broad biological activities. In this context, this work is based on the evaluation of the antimicrobial activity of Quercus robur L. leaves extracts (Family of Fagaceae). Methods: Firstly, the collected plant material was defatted; then, the extraction of tannins and saponins was carried out according to a standard protocol where the extracts obtained were tested on some uropathogenic microbial strains by disk diffusion method with the determination of the Minimum Inhibitory Concentrations (MICs) by broth macro-dilution method. Results: The extraction yield of the selective extracts was 7.93 and 16.94% for tannins and saponins, respectively. The antibiotic resistance profile of the tested strains showed a resistance relatively important to several antibiotics, namely amoxicillin +clavulanic acid and ampicillin for Escherichia coli, while Pseudomonas aeruginosa showed resistance to amoxicillin+clavulanic acid, amikacin, cefotaxime and ceftazidime. However, Staphylococcus aureus was susceptible to penicillin, gentamicin, ofloxacin and chloramphenicol. Antifungal susceptibility testing has been shown that Candida albicans was susceptible to amphotericin B, econazole and it was clinically categorized as intermediate to miconazole drug. For antimicrobial tests, the tannins and saponins extracts exhibited a low to strong inhibitory effect at tested concentrations lower than 30 mg/mL (ranged from no inhibition to an inhibition zone diameter of 17.5 mm), depending on dose levels and tested microbial strains. Conclusion: This activity is proportional to the tested concentrations, knowing that tannins extract was more active compared to saponins extract. For this, Q. robur could constitute an important source for drug discovery.

This study aims to evaluate the anti-inflammatory and antioxidant effects of N. gaditana on streptozotocin (STZ)-induced diabetes mellitus in Wistar rats. Diabetes was induced in male Wistar rats by single intraperitoneal injection of STZ (45 mg/kg). Male rats were fed on control diet supplemented or not with N. gaditana (10%) for a period of 2 months. At the end of the experiment, biochemical parameters and oxidant/antioxidant markers in liver and pancreas tissues, as well as mitochondria isolated from liver of rats, were determined. It was notice that levels of glucose, glycated hemoglobin (HbA1c), lipid profile, kidney functions and liver enzymes in addition to markers of the inflammatory reactions interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) increased significantly (P

Milk and dairy products’ production lines generate pollution in the form of food waste. The management of this waste concerns professionals that fit the purpose of this study to assess the chemical risk of the raw liquid effluents that are discharged from a milk processing plant located in Bechar (Southwest of Algeria) by analyzing the main chemical indicator parameters of water pollution following official analytical methods. A total of ten samples were analyzed during the months of February, March and April of the year 2019. The obtained results were interpreted according to the regulatory requirements recommended by the Algerian standard related to threshold limit of physicochemical parameters’ values. The obtained results showed pollution signs revealed by high levels of the organic matters, expressed by significant means related to the following parameters: chemical oxygen demand (COD: 810.33 mg/L), 5 days-biochemical oxygen demand (BOD5: 797.91 mg/L), total suspended solids (TSS: 47.3 mg/L) and turbidity (174.014 NTU) exceeding those required by the national standard, except other physicochemical parameters, such as pH, conductivity, sulfate, nitrate and nitrite contents that did not exceed the threshold of acceptable values. Although these raw effluents present a high organic load expressed by average BOD5/COD ratio equal to 0.985, they constitute organic matters in a dissolved form (average value of the TSS/BOD5 ratio = 0.076). Furthermore, The COD/BOD5 ratio that had an average value equal to 1.015 underlines the biodegradability character of discharged dairy effluents. The high pollution levels which are aggravated by the lack of wastewater treatment can hurt the environment and the biological diversity and, therefore the humans' health. This requires an immediate intervention for a solution, where it is very important that proper wastewater treatment systems should be installed for the environment protection and for the ecological balance. Otherwise, it may constitute a risk to the public health on medium- to long-term by affecting the quality of the underground reservoir known as the main source of supply for the inhabitants of arid and semi-arid areas.

In this article, advanced tools are provided to steppe specialists to guide them in choosing the integrated development policies for steppe and pastoral zones. To this end, the use of adapted mobile wireless sensor networks (WSN) is proposed. Thus, a distributed and localized protocol dealing with the self-deployment problem resulting from mobile sensor random deployment is presented, on a steppe rangeland. This scheme entirely based on a geometric approach dealing with geodesy and steppe zones characteristics, allows mobile sensors moving to optimal positions on these study rangelands. The Geodesic Efficient Self-Deployment Algorithm in Steppe Zones (sz-GESA), so called, in its approach to solve the self-deployment problem for a given geographical rangelands type, showed during simulations a great robustness for the WSN adapted to this kind of zones by allowing optimization of the coverage and to idealize the connectivity. Obtained results are very encouraging and let us think for more research enhancing this developed system more efficiently.

Choreographies prescribe the rendez-vous synchronisation of messages in a communicating system. Such a system is called realisable, if the traces of the prescribed communication coincide with those of the asynchronous system of peers, where the communication channels either use FIFO queues or multiset mailboxes. It has recently been shown that realisability can be characterised by two necessary conditions that together are also sufficient, whereas in general the synchronisability of communicating peers is undecidable. The sufficiency of the conditions permits the construction of correct communicating systems; their necessity shows that all choreography-defined communicating system can be obtained in this way. This article provides an integrated framework based on Event-B for such a construction with a major emphasis on Rodin-based proofs of correctness and completeness.

Background: Meat is the first source of animal protein, its richness in essential amino acids classifies it among the noble proteins. However, due to its nutritional qualities, meat constitutes a favorable ground for microbial development and can serve as a source of foodborne pathogens for consumers. Hence this study aimed to evaluate the hygienic quality of fresh camel meat marketed in Bechar city (Southwest of Algeria). Methods: At the butcher’s shops in the Bechar El Djadid’s market, the taken samples underwent analyzes of a few physicochemical and microbiological parameters. The suspected pathogenic isolates were confirmed using biochemical tests. Result: The physicochemical parameters results showed that the samples had slightly acidic pH values ranging from 5.25 to 5.86, the temperature from 6 to 7.5°C and the total solid content (TSC) ranging from 21 to 36.6% with a moisture rate ranging from 63.4 to 75.6. However, the obtained microbiological results showed a load of Escherichia coli of 3.3 and 4.83 Log10 CFU/g for the samples S1 and S2, respectively, exceeding the threshold set by national standards. The analyzed samples had a load of S. aureus (CoPS) ranging from 3.78 to 5 Log10 CFU/g, with the presence of Salmonella choleraesuis ssp arizonae for the sample (S1), while both Listeria monocytogenes and Pseudomonas spp species were absent in all the analyzed samples. The lactic acid bacteria (LAB) load ranged from 2.36 to 2.74 Log10 CFU/g. In conclusion, four out of five analyzed samples had an unsatisfactory quality. This is the result of a lack of hygiene in one of the links in the raw material supply chain, from the slaughterhouse to the retailer, whose stakeholders must ensure cleanliness and compliance with good hygiene practices (GHP) to protect consumers against microbial risks.

Background: Traditional dairy products are widely consumed by the Mediterranean and sub-Saharan countries; they are traditionally prepared by rural women. This work focuses on understanding the traditional practices and enhancing the same by studying the physicochemical, bacteriological and organoleptic properties of fermented raw goat milk, supplemented by the leaves of the Phenician juniper species. Methods: Monitoring of the juniper leaves-supplemented goat milk sample against a control one (without juniper leaves) was conducted. Three physicochemical parameters were tracked: pH, titratable acidity and temperature. However, the bacteriological analysis featured the following parameters: the total aerobic mesophilic flora, thermotolerant coliforms, coagulase-positive Staphylococci, Pathogenic bacteria namely Salmonella spp and Listeria monocytogenes, while the sensory test was based on the descriptive and hedonic analyses. Result: The obtained physicochemical results showed a significant change in the pH and the titratable acidity parameters of the test sample compared to the control sample. This change was marked by an increase in the total aerobic mesophilic flora load (due to the fermentation phenomenon) and a decrease in the thermotolerant coliforms and the coagulase-positive Staphylococci loads for the test sample compared to the control test. A total absence of Salmonella spp and L. monocytogenes as pathogenic microorganisms was also notified for both samples. The qualitative phytochemical screening carried out on the J. phoenicea L leaves showed the presence of several compounds known as constituents having an antimicrobial effect. On the sensory level, the control sample was characterized by a milky and acidic taste, while the herbaceous taste due to the components of the Phenician juniper leaves characterizing the test sample gave it a lower score on the established rating scale. A vision to maintain this type of artisanal practice, traditional knowledge and preserve this important indigenous wealth become necessary which contributes to improving the hygienic, sensory quality and shelf-life of the fermented goat milk.

Background: IMMUcan (SPECTA NCT02834884) is a European public-private effort to generate molecular and cellular profiling data of the human tumor microenvironment (TME) from up to 3,000 patients, to better understand how the immune system and tumors interact. Triple-negative breast cancer (TNBC) is a heterogenous disease with distinct molecular subtypes characterized by different gene expression, genomic profiles, and clinical outcomes. Here, we explored the association between molecular subtypes and response to neoadjuvant chemotherapy as well as levels of immune cell infiltration in the prospective IMMUcan TNBC cohort. Methods: At the cut-off date on June 29th, 2022, we identified a first cohort of 132 patients to perform preliminary analyses, of which 109 had pre-treatment RNAseq data available. Among those, pathological Complete Response (pCR) information was available for a total of 86 patients. Preliminary data included the density of CD3+, CD20+ and CD8+ immune cells from the stroma and tumor compartments from multiplex-immunofluorescence (mIF) for 69 patients. TNBC subtypes were computed as described by Bareche et al. Association of continuous variables with pCR was evaluated with logistic regression (univariate analysis). Results: The pCR rates differed across TNBC subtypes (Fisher’s test, P = 0.02). In detail, pCR was achieved in 88% (8/9) of basal like (BL), 63% (17/27) of immunomodulatory (IM) and 45% (16/35) of mesenchymal (M) tumors, while lower pCR rates were observed for the mesenchymal stem-like (MSL) and luminal androgen receptor (LAR) subtypes with 37% (3/8) and 14% (1/7), respectively, suggesting differences in the sensitivity to neoadjuvant chemotherapy in line with previous reports. When considered as continuous signature scores, pCR was positively associated to BL levels (OR = 2.7, 95% CI, 1.5-4.8; False Discovery Rate [FDR] = 0.0031), and negatively associated to MSL and LAR signature levels (OR = 0.53, 95% CI, 0.32-0.87; FDR = 0.019; OR = 0.30, 95% CI, 0.12-0.74; FDR= 0.019). In addition, CD3+ cell densities in the tumor and stroma were significantly higher in IM tumors (P = 0.002 and P < 0.001), while lower levels were found in M tumors (P = 0.005, P = 0.002). Similarly, stromal CD20+ levels were higher in IM tumors (P = 0.008) and lower in M tumors (P = 0.006), suggesting a more immunosuppressive TME in the M subtype. CD8+ cells levels were not significantly different between subtypes. Conclusions: These preliminary results show relevant differences in the pCR rates among TNBC subtypes, to be confirmed on a larger series of patients and further suggesting a substantial TNBC heterogeneity regarding treatment response. Of note, preliminary mIF results suggest a differential role of the immune response across molecular subtypes. Additional analyses integrating mIF and genomic data are currently ongoing. Funding: IMI2 JU grant agreement 821558, supported by EU’s Horizon 2020 and EFPIA. Citation Format: Andrea Joaquin Garcia, Mattia Rediti, Abdelkader Benyagoub, Stéphanie Tissot, Sylvie Rusakiewicz, Robin Liechti, Flavia Marzetta, Nicolas Penel, Julio Oliveira, Jean-Charles Goeminne, Pierre Fournel, Andreia Capela, Xiaoxiao Wang, Delphine Vincent, Françoise Rothe, Marie Morfouace, Henoch Hong, Donald Jackson, Christos Sotiriou, Laurence Buisseret. Pathologic complete response rate across triple negative breast cancer subtypes in the IMMUcan study. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4522.

Angstrom-confined solvents in 2D laminates can travel through interlayer spacings, through gaps between adjacent sheets, and via in-plane pores. Among these, experimental access to investigate the mass transport through in-plane pores is lacking. Our experiments allow an understanding of this mass transport via the controlled variation of oxygen functionalities, size and density of in-plane pores in graphene oxide membranes. Contrary to expectations, our transport experiments show that higher in-plane pore densities may not necessarily lead to higher water permeability. We observed that membranes with a high in-plane pore density but a low amount of oxygen functionalities exhibit a complete blockage of water. However, when water- ethanol mixtures with a weaker hydrogen network are used, these membranes show an enhanced permeation. Our combined experimental and computational results suggest that the transport mechanism is governed by the attraction of the solvents toward the pores with functional groups and hindered by the strong hydrogen network of water formed under angstrom confinement.

International audience; In this work, we present first experimental results on the micro-structuration of monocrystalline strontium titanate (100)-SrTiO3. A self-organized structure appears on its surface due to irradiation with 0.71 MeV/u 129Xe23+ and 0.55 MeV/u 136Xe19+ swift heavy ions at room temperature and under grazing incidence. The resulting wave-like structure appears normal to the direction of the ion beam. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses were undertaken to probe microstructural properties below the surface, revealing in particular surface amorphization at high fluences. Such amorphous surface layers, further irradiated at high fluences, may lead to an anisotropic plastic deformation (hammering) effect, inducing the observed self-organized structure due to the grazing angle configuration. This surface morphology was characterized by atomic force microscopy (AFM). A dependency of the periodicity as well as the width of the undulations on the irradiation angle was found as they evolve in the same way. As the ripple formation depends on the irradiation parameters, the characteristics of these patterns can be controlled and thus opens the possibilities for custom surface structuration.

Since independence, Algeria has continued to spend massive sums on importing milk powder to satisfy local demand. In recent years, the state has improved several development programs to overcome this situation. Thus, this work aims at studying the cost price/quality relationship of a strategic product for wide consumption (Milk and dairy products) and describing the state subsidy policy regarding the safety of milk. To achieve these objectives, we proceeded on the one hand, to carry out a hygienic quality analysis of 50 samples of packaged pasteurized milk, calculating their cost price at the private dairy factory of Adrar (Algeria) and, on the other hand, to analyze recently published official statistics and the various programs adopted by the Algerian state when defining this policy. According to the results obtained it appears that the state subsidy contributes toward covering the demand of the national market but with a high dependence on the importation of raw material (about 30%). The results of the bacteriological analysis were in the range of thresholds set by the national standard. The analysis of spending data given by the tcr showed that for this factory, the cost price of one liter of pasteurized milk is estimated at 27.79 dzd/l compared a quay-factory fixed selling price at 23.20 dzd/l, revealing a deficit of -3.79 dzd/l (-13.64%), while, produced fermented milk (sour milk) showed a profit of +10.65 dzd/l representing a margin of distribution equivalent to (+37.56%) of the cost price that estimated at 28.35 dzd/l. Nevertheless, it is essential that the state contributes to the training and support of farmers, collectors and the dairy factory, which appear disconnected from the local production sector that supplies it with fresh raw milk; besides, it must focus on typical farms, which seem to be more productive than family small-sized farms. These must come together and form cooperative, not only so as to be in the official circuit but also to be under a hygienic control system in order to avoid any kind of peril to consumer’s health.

Background: The microbial infections represent a real public health problem with considerable individual and economical consequences. Their surveillance has become, in recent decades, an essential element of any program to control these infections. Aim: In this study, we estimated the prevalence and frequencies of some microbial infections amongst the Bechar’s community (Algeria). Methods: The microbiological analyzes of various pathological samples namely : urine and vaginal discharge, pus, nipple discharge, originally sampled from throat, otitis discharge and effusion liquid, have been carried out in the medical analysis laboratory of Bechar for seven months. Results: The obtained results showed that out of 1458 samples, 506 cases were positive (34.7 %), for some infections, there is a relationship correlation between the infections’ frequency and their prevalence with the age and gender of patients, as factors; which the female gender presents 74.7 % of positive cases, a sex-ratio less than 1; besides, the most affected population is aged between 25 and 39 years old. The isolated microbial species, which are the most incriminated agents responsible for the studied infections, were mainly Escherichia coli with an isolation frequency of 87.15 %, followed by coagulase-positive Staphylococci CoPS (5.13 %), Streptococcus sp (3.16 %), fungal species Candida albicans (1.58 %), Coagulase-negative Staphylococci Co NS (1.18 %). However, less than 2 % of infectious agents were recorded for the bacterial strains P. aeruginosa, K. pneumoniae and Enterococcus sp. Conclusion : This study can provide a platform for an effective prevention strategy and can be useful for epidemiological prediction with a decision-making. Bangladesh Journal of Medical Science Vol.19(3) 2020 p.404-413

Building floor systems are made from steel girders connected to a concrete slab or a composite slab with ribbed decking. In office buildings with large free span areas, different technical and economic constraints lead to a substantial reduction of the floors thickness, by providing openings in the webs of beams designed to allow the passage of pipes and ducts. The web openings may have a significant effect on the deflection of beams subjected to transverse loading and in many cases, be the paramount parameter in their design. In this paper, an analytical model previously developed for the evaluation of total deflection of composite symmetric cellular beams has been improved, through a better consideration of the flexural stiffness of the beam webs under vertical shear forces. The analytical results presented are compared against other existing proposals in the literature then verified against the numerical solutions obtained using the Cast3m software.

The medicinal value of the plants is due to their chemical components that bring a definite physiological action on the human body to prevent the diseases. In this work, we investigated the antimicrobial activity of leaves’ extracts of Quercus robur L., collected from the Algerian upper highlands, on ten bacterial strains and one fungal strain known to be pathogenic. First, we performed a qualitative phytochemical analysis, and second, antimicrobial activity tests performed by agar diffusion method (disc and well) with the determination of MIC by broth macro-dilution method. Given the results, it appears that obtained macerates of Quercus robur L. were rich in bioactive phytoconstituents such as alkaloids, anthraquinones, saponins, tannins, and other components. The yield of aqueous and methanolic macerates of leaves was 8.5 ± 1.41 and 22.4 ± 4.36%, respectively. The bacterial resistance was relatively important to several antibiotics, namely, ampicillin, amoxicillin + clavulanic acid for strains of Escherichia coli and Salmonella sp. However, Staphylococcus aureus strains were resistant to fusidic acid, penicillin, and oxacillin; while Enterococcus faecalis was resistant to fusidic acid, penicillin, oxacillin, and ticarcillin. The antibacterial activity of the macerates toward tested microbial strains showed that the aqueous and methanolic macerates of the leaves were proportional to the tested concentration and active not only against Gram-positive and Gram-negative bacteria but also on the fungal species Candida albicans. The estimated MIC for Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus was in the order of 10 mg/mL, which seems more effective than toward Salmonella sp., Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans which were in the order of 30 mg/mL. These preliminary results confirm that the part of the studied plant had a very good antimicrobial activity that was proportional to the serial concentrations of the tested extracts.

In Algeria, the production of dates occupies a large part of Saharan agricultural production. The wilaya of Bechar is one of the most productive regions for dates, where more than half of their production is considered as a second quality dates which are sold by barter or used as animal feed. Families in these regions use this type of date to prepare by-products, namely; date syrup locally called "Robb". The preparation of this type of product is limited and confined to the individual scale. The aim of this study is to highlight the physicochemical and the biochemical quality of this home-prepared artisanal product by comparing it to two others marketed in the wilaya of Béchar and of Elbayadh (Algeria). The physicochemical and the biochemical results of the three analyzed samples showed an acidic pH value ranged from 4,26 to 4,7, a degree of acidity ranging from 8,2 to 12%, a soluble solids content of 64 to 75%, a total sugars and reducing sugar content of 51 to 63,6 and 40 to 52% respectively. While the water content is relatively high ranging from 28 to 37%, and a significant potassium ions content compared to sodium ions varies from 195 to 555 and from 5,8 to 137mg/L respectively. These characteristics are not only considered as a high added value to the product which enhances the value of the second-quality low marketing dates but also contributes to increasing their shelf life, constituting an economic priority for the oasis’ inhabitants of the Southern Algeria region.

This present work is a part of the liquid discharges treatment topic by studying the removal performance for thermotolerant coliforms (FC) and fecal streptococci (F.Strep) by a local natural light green clay from Kenadsa (Bechar-Algeria) under continuous adsorption processes in a fixed-bed column. The study estimated the clay adsorbing efficiency by the adsorption technique for bacteria contaminating the dairy effluent by determining the bacterial load before and after treatment. The mean log counts per 100 ml for FC and F.Strep were assessed by MPN method on liquid medium. The clay material characterizations were made through X-ray diffraction, X fluorescence spectrometry and Fourier transform infrared spectroscopy analysis. Besides, some parameters were estimated such as the breakthrough time tb (clay filter breakdown); the amount of the contaminating bacteria that was removed at the breakthrough time Xb and the exhaustion of disinfection capacity Xe; the total amount of contaminating bacteria flowing through the column Xtotal; and the total removal efficiency (Y). According to the XRD, XRF and FTIR results, the predominant mineral constituents were silicon dioxide, aluminum oxide, ferric oxide and magnesium oxide with rates of 59,44; 18,09; 7,79; and 3,87%, respectively, and hence, their classification among non-swelling clay minerals, illite is the major mineral group of this material. The results of the bacteriological analysis of raw dairy effluents showed an average bacterial load of 3,88 Log10 and 4,1 Log10 CFU/100 mL for FC and F.Strep, respectively, exceeding the thresholds set by the national and the international regulations. The results of the dairy effluents treated by the tested material have shown that the used clay has a relatively high adsorption property for the clay fixed-bed system (3 cm of bed height), expressed by a total removed efficiency Y (%) of FC and F.Strep used to evaluate the column performance ranging from 55 to 84%. It gives a higher log removal for FC and F.Strep (0.98–1.65 Log10) reported from the first adsorption process, and a breakthrough time ranged from 100 to 250 min, which was inversely proportional to the initial bacterial load of discharges and also linked to the nature of the bacterial contaminants. When the breakthrough occurs earlier, the column service life will be shortened. For the studied parameters, the results of treated effluent complied with national and WHO regulations for unrestricted agricultural irrigation, otherwise, as authorized effluents to be discharged into nature without risks. These preliminary results are very promising at laboratory scale as an innovative green technology, treatment method respecting the environment and opens up prospects for the future, where the modification or the optimization of operating conditions such as the bed height of the fixed bed for adsorption, the volumetric flow rate or the clay structure like the particle size distribution of the adsorbents, known as one of the adsorbent classes endowed with an antimicrobial property, can improve the column performance, and further, the removal or even more the disinfection process by adsorption method.

Choreographies prescribe the rendez-vous synchronisation of messages in a system of communicating finite state machines. Such a system is called realisable, if the traces of the prescribed communication coincide with those of the asynchronous system of peers, where the communication channels either use FIFO queues or multiset mailboxes. In this article we generalise choreographies to control-state choreographies, which enable parallelism. We redefine P2P systems on grounds of control-state machines and show that a control-state choreography is equivalent to the rendez-vous compositions of its peers and that language-synchronisability coincides with synchronisability. These results are used to characterise realisability of control-state choreographies, for which we prove two necessary conditions: a sequence condition and a choice condition. Then we also show that these two conditions together are sufficient for the realisability of control-state choreographies.

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International audience; Nanoporous graphene displays salt-dependent ion permeation. In this work, we investigate the differences in Donnan potentials arising between reservoirs, separated by a perforated graphene membrane, containing different cations. We compare the case of monovalent cations interacting with nanoporous graphene with the case of bivalent cations. This is accomplished through both measurements of membrane potential arising between two salt reservoirs at different concentrations involving a single cation (ionic potential) and between two reservoirs containing different cations at the same concentration (bi-ionic potential). In our present study, Donnan dialysis experiments involve bivalent MgCl 2 , CaCl 2 , and CuCl 2 as well as monovalent KCl and NH 4 Cl salts. For all salts, except CuCl 2 , clear Donnan and diffusion potential plateaus were observed at low and high salt concentrations, respectively. Our observations show that the membrane potential scaled to the Nernst potential for bivalent cations has a lower value (≈50%) than for monovalent cations (≈72%) in the Donnan exclusion regime. This is likely due to the adsorption of these bivalent cations on monolayer graphene. For bivalent cations, the diffusion regime is reached at a lower ionic strength compared to the monovalent cations. For Mg 2+ and Ca 2+ , the membrane potential does not seem to depend upon the type of ions in the entire ionic strength range. A similar behavior is observed for the KCl and NH 4 Cl membrane potential curves. For CuCl 2 , the membrane potential curve is shifted toward lower ionic strength compared to the other two bivalent salts and the Donnan plateau is not observed at the lowest ionic strength. Bi-ionic potential measurements give further insight into the strength of specific interactions, allowing for the estimation of the relative ionic selectivities of different cations based on comparing their bi-ionic potentials. This effect of possible ion adsorption on graphene can be removed through ion exchange with monovalent salts.

PURPOSE: This study aims to evaluate the anti-inflammatory and antioxidant effects of N. gaditana on streptozotocin (STZ)-induced diabetes mellitus in Wistar rats. METHODS: Diabetes was induced in male Wistar rats by single intraperitoneal injection of STZ (45 mg/kg). Male rats were fed on control diet supplemented or not with N. gaditana (10%) for a period of 2 months. At the end of the experiment, biochemical parameters and oxidant/antioxidant markers in liver and pancreas tissues, as well as mitochondria isolated from liver of rats, were determined. RESULTS: It was notice that levels of glucose, glycated hemoglobin (HbA(1c)), lipid profile, kidney functions and liver enzymes in addition to markers of the inflammatory reactions interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) increased significantly (P

The present work aims to study the biological activity of Anastatica hierochuntica L., against four bacterial strains considered as toxigenic responsible for food-borne infection. The plant was collected from Tindouf region (Far Southwest of Algeria). In this study we performed a phytochemical screening and evaluation of antibacterial activity of three macerates of two vegetative parts (seeds and stems) by two methods (disk and wells diffusion method). The yield of aqueous, methanolic and etheric macerates of the seeds and stems were (5.1; 3.8), (5; 1.4) and (2; 0.95)% respectively. Also, it appears that macerates obtained were rich in bioactive phyto-constituents particularly the seed of the plant. They showed the presence of ten large chemical groups. The antibiotic resistance profile of the bacterial strains tested showed an increased resistance to several families of antibiotics. The evaluation of the antibacterial activity of the extracts showed that methanolic and aqueous macerates of the seed were more active against Gram positive bacteria. The methanolic macerate of the stems was less active. However, other macerates were ineffective. The results obtained show that the plant has an average antibacterial activity and that depends on extract concentration used.Microbes and Health, June 2017, 6(1): 5-8

*Corresponding author: marko.karlusic@irb.hr When a beam of swift heavy ions (SHI) impinges onto a material, the formation of defects called ion tracks is possible as a result, either in the bulk or on the surface of the material. As a consequence, effects produced by means of SHI irradiation that lead to structural changes of the material can be used to modify the properties of the material via defects engineering. SHI damage introduction to materials can result in complex behavior, especially in radiation harsh environments. To assess the final damage of the material, the effect of the energy deposition from the ions to the atoms within the material must be taken under consideration. Deposition of energy occurs through two main channels: either to the electronic subsystem of the material (electronic stopping power) or to the nuclei (nuclear stopping power). Here we investigate the influence of ion beams with different stopping powers, used in a sequence, on defects formation. It is known that sequential irradiation of ion beams can lead to the SHIBIEC effect (Swift Heavy Ion Beam Induced Epitaxial Crystallization) i.e. the annealing of defects that occurs during the second irradiation step. Alternatively, the anti- SHIBIEC effect is also possible, i.e. the enhanced defect formation during the second step of irradiation. Sequential ion irradiation of GaN has not been investigated so far. This material is an important semiconductor for high-power electronics. The results presented here are of importance for basic research in this field as well. In our previous work [1], we found no evidence of ion track formation in the bulk after SHI irradiation using 23 MeV I and 90 MeV Xe beams. However, recently we were able to introduce additional disorder into moderately damaged GaN crystals using the same 23 MeV I and 90 MeV Xe beams, in cases where GaN samples have been pre-irradiated with 2 MeV Au or with 900 MeV Xe ion beams. Two different ion beams are expected to introduce damage into GaN either by nuclear or electronic stopping, respectively [2, 3]. We observe the difference in total damage in the material depending on the fluence of the beams applied. In this contribution, we report new results of sequential ion irradiation of GaN based on RBS/c (Rutherford Backscattering Spectroscopy in Channeling) and TEM (Transmission Electron Microscopy) measurements. [1] M. Karluši? et al., Response of GaN to energetic ion irradiation - conditions for ion track formation, J. Phys. D: Appl. Phys. 48 (2015) 325304 [2] S.O. Kucheyev et al., Ion implantation into GaN, Mat. Sci. Eng. 33 (2001) 51 [3] M. Sall et al., Track formation in III-N semiconductors irradiated by swift heavy ions and fullerene and re-evaluation of the inelastic thermal spike model, J. Mater. Sci. (2015) 50:5214–5227

Despite the improvement of the quality of CVD grown single-layer graphene on copper substrates, transferring the two-dimensional layer without introducing any unintentional defects still poses a challenge. While many approaches focus on optimizing the transfer itself or on necessary post-transfer cleaning steps, we have focused on developing a pre-treatment of the monolayer graphene on copper to improve the quality and reproducibility of the transfer process. By pressing an ethylene-vinyl acetate copolymer foil onto the monolayer graphene on copper using a commercially available vacuum bag sealer graphene is stabilized by the attachment of functional carbon groups. As a result, we are able to transfer graphene without the need of any supporting layer in an all-H2O wet-chemical transfer step. Despite the general belief that the crumbling of graphene without a support layer in a H2O environment is caused due to differences in surface energy, we will show that this assumption is false and that this behavior is caused rather by the polar interactions between graphene and water. Suppressing these interactions protects graphene from ripping and results in extremely clean, highly crystalline graphene with a coverage close to 100%.

Choreographies prescribe the rendez-vous synchronisation of messages in a communicating system. Such a system is called realisable, if the traces of the prescribed communication coincide with those of the asynchronous system of peers, where the communication channels either use FIFO queues or multiset mailboxes. It has recently been shown that realisability can be characterised by two necessary conditions that together are also sufficient, whereas in general the synchronisability of communicating peers is undecidable. The sufficiency of the conditions permits the construction of correct communicating systems; their necessity shows that all choreography-defined communicating system can be obtained in this way. This article provides an integrated framework based on Event-B for such a construction with a major emphasis on Rodin-based proofs of correctness and completeness.

Choreographies prescribe the rendez-vous synchronisation of messages in a system of communicating finite state machines. Such a system is called realisable, if the traces of the prescribed communication coincide with those of the asynchronous system of peers, where the communication channels either use FIFO queues or multiset mailboxes. In a recent article realisability was characterised by two necessary conditions that together are sufficient. A simple consequence is that realisability in the presence of a choreography becomes decidable. In this article we extend this work by generalising choreographies to control-state choreographies, which enable parallelism. We redefine P2P systems on grounds of control-state machines and show that a control-state choreography is equivalent to the rendez-vous compositions of its peers and that language-synchronisability coincides with synchronisability. These results are used to characterise realisability of control-state choreographies. As for the case of FSM-based choreographies we prove two necessary conditions: a sequence condition and a choice condition. Then we also show that these two conditions together are sufficient for the realisability of control-state choreographies., Comment: 32 pages, 6 figures, 28 references

Contemporary interaction‐based complex systems are often built by reusing existing distributed peers, which have to coordinate with each other to fulfill the client, system, and environmen...

This study is a part of the valorization of extract from three most commonly used Algerian spices, namely; caraway and cumin seeds and cinnamon bark. On the one hand, it aims at characterizing the chemical indices of extracted essential oils and evaluating the antibacterial activity of each essential oil by titration and disc diffusion method respectively. On the other hand, it attempts at evaluating the combined action of essential oils against four reference pathogenic bacterial strains, namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis by well and Chabbert-type diffusion method. The essential oils obtained by the hydrodistillation method have a relatively average extraction about 1.43, 2.3 and 2.5%, respectively for caraway, cumin, and cinnamon. The acid index indicates the behavior and amount of free acids present in the essential oil, in which the acid and saponification indices of cinnamon essential oil indicate a value of 4.48 and 168.56 respectively. It can also inform us about the susceptibility of the oil to undergo alterations. The antibacterial activity results showed that cinnamon essential oil (EO) proved to be the most active against the tested bacterial strains; caraway EO was active against Enterococcus faecalis, and the antibacterial action of cumin EO was the lowest. However, the association of the extracted essential oils has a higher synergistic effect than the independent effect of each essential oil, in which the MIC value found was estimated at 10 to 20 (V/V), 40 to 50 (V/V) and 50 to 70 (V/V) respectively for cinnamon, cumin and caraway. The obtained results show that the response to the antibacterial activity varies according to the plant species used and the extract tested alone or in combination.

In this work, we are interested in studying the investment challenges of packaged reconstituted milk production in Southwest of Algeria. To reach this objective, we have calculated the cost price of two products (pasteurized milk and fermented milk) which present the main production line of the dairy factory of Bechar, to assess the profitability of the company. The cost price of milk was calculated from the general balance that shows all the movements of the accounts which we have established the table of counting results ‘TCR’ corresponding to the different charges directly related to the milk manufacturing. The analysis of spending data showed that for this factory, the cost price of one liter of pasteurized milk was estimated at 27.06 DZD/L compared to fixed selling price at the dairy factory level (23.20 DZD/L), which reveals a deficit of -3.86 DZD/L (-16.63%), while produced fermented milk showed a profit of +14.65 DZD/L representing a margin of distribution equivalent to (+60.16%) of the cost price that was estimated at 24.35 DZD/L. This study provides a platform which can be used, not only, to define the ability of dairy factory to overcome competitive market challenges, but also the pre-requisite programs (PRP) installation challenges required to implement a quality system promoting the quality of milk and dairy products.

International audience; This communication deals with experimental results crucial for the sizing of picosecond LIBS measurements dedicated to the determination of tritium density profiles in the plasma facing components. Ablation properties in single pulse on aluminum (considered as a surrogate of beryllium) and tungsten have been obtained for 532 and 1064 nm picosecond laser pulses. Then, double pulse experiments have been performed to estimate the role played by the second pulse on the spectral radiance observed for lines representative of the ionization degree of the plasma and possible observation of low radiance lines.

This study focused on the analysis of twenty-four samples of camel raw milk commercialized at the market of Bechar city. Sample analysis of raw milk was performed by measuring of some physicochemical parameters which the average results obtained have a slightly acidic pH (5.67), high titratable acidity (4.49g/l). Density, total dry extract and fat content were low (1.0268; 89g/l and 29.87g/l respectively), a lactose content of (28.18 g/l). The microbiological examination has several microbial quality attributes such as total bacteria, thermo tolerant coliforms, fecal Streptococci, Sulphite-reducing clostridia and fungal flora with average obtained 3.1 x 107 cfu/ml, 4.9 x 104 cfu/ml, 1.16 x 10 germ/ml, less than 5 spore/20ml and 2.36 x 103 uf/ml respectively. In addition, the analysis revealed the presence of coagulase positive Staphylococci for two samples, however, all samples are free of Salmonella sp. and Shigella sp. 58% of the samples were of satisfactory quality, 8.33% are acceptable and 33.33% are unacceptable.Microbes and Health, January 2015. 4(1): 14-18

In radiation hard materials there is a rather high threshold in incoming ion energy below which ion track formation does not occur. However, this threshold can be significantly reduced by low energy pre-irradiation. As an example, previous studies on GaN found the threshold to be at about 20 keV/nm electronic stopping power for ion incidence close to normal to surface. It has been lowered down to 8 keV/nm after pre-irradiation by 2 MeV Au ions. This has been confirmed by RBS/c and AFM measurements where change in surface roughness has been found. Grazing incidence swift heavy ion irradiation effectively increases volume density of the absorbed energy leading to higher concentration of the formed defects. It also results in lowering of the ion track formation threshold. This has been studied in MgO, Al2O3 and MgAl2O4. Earlier results proved these materials to be radiation hard, and the threshold for the track formation is found to be in 10-15 keV/nm range for nearly normal irradiation. Switching to grazing incidence reduces the threshold down to 8 keV/nm. Here, the tracks are clearly visible on surface by AFM.

Behavior of materials in radiation harsh environment is an important issue and damage build-up within the material in such environment can exhibit complex behavior. Therefore, as one of the most prominent candidate materials that can be used in radiation harsh environments, response of GaN to ion irradiation should be studied in detail. Dense electronic excitation in the wake of the swift heavy ion passage through a material (mass > 20 amu, kinetic energy > 1 MeV/amu) can lead to nanoscale material damage along ion trajectory called ion track [1], [2]. Irradiation with heavy ions in the keV energy range can also produce defects but via different energy dissipation channel. In this case, it is well known that direct ion-atom collision (i.e. nuclear energy loss) can produce defects in GaN [3]. In our previous study [1], we found no evidence of ion track formation in the bulk after swift heavy ion irradiation using 23 MeV I and 90 MeV Xe beams. Recently, synergistic effects of nuclear and electronic energy loss came into research focus. After introducing additional disorder into moderately damaged GaN crystals via pre-irradiating them either with 2 MeV Au or with 900 MeV Xe ion beams, we were able to introduce additional damage using the same (as in our previous study [1]) 23 MeV I and 90 MeV Xe ion beams. Here, we report the results of sequential ion irradiation of GaN based on the RBS/c, TEM and AFM measurements. [1] M. Karlušić et al., Response of GaN to energetic ion irradiation - conditions for ion track formation, J. Phys. D: Appl. Phys. 48 (2015) 325304 [2] M. Sall et al., Track formation in III-N semiconductors irradiated by swift heavy ions and fullerene and re-evaluation of the inelastic thermal spike model, J. Mater. Sci. (2015) 50:5214–5227 [3] S. O. Kucheyev et al., Ion implantation into GaN, Mater. Sci. Eng., R , 33 (2001) 51-107

Although today’s software systems are distributed by necessity, their design verification and validation is still an open issue due to their ever-increasing complexity. This paper proposes a stepwise development method allowing a designer to build correct-by-construction distributed systems. System correctness is handled w.r.t.a realizability property. We assume a top-down approach where systems are specified with a global behavioral model referred to as conversation protocol (CP). This specification defines all allowed sequences of messages exchanged between distributed peers implied in that conversation. Given a CP, realizability is defined whether there exists a set of peers such that their interaction with each other leads to the same sequences as specified by the original CP. Our proposal ensures that the built CP is realizable-by-construction. We define a set of sufficient conditions preserving realizability at CP level. We then propose an algebra of operators for incremental CP building w.r.t.to the defined conditions. We also prove that our proposal is correct and we show how this is supported with mechanized proofs. Lastly, we implemented our approach using Rodin platform and validated it on several case studies.

The Communal Hygiene Office (CHO) is a technical service part of the town, responsible for ensuring the cleanliness and public safety of the population. In this work, a retrospective study of the missions of the Municipal or Communal Hygiene Service of Bechar (Algeria) for the period from 2015 to 2017 is made according to the decree 87-146 of June 30 (1987) relative to the creation of the CHO. The results showed the role of CHO in hygiene and public health, prevention of food poisoning, control of waterborne diseases and zoonotic diseases which rate 60 % of missions (average of 6 inspections per year) aim at hygiene and sanitation in food-related commercial premises. There is an increase in the number of commercial premises due to the growth of the city and that the CHO tries to be dynamic towards this development. Moreover, the improvement in commercial premises with the awareness of the tradesmen is remarkable. This is attributed to the role of CHO in awareness and prevention action rather than repressive action. The authorities must provide the CHO with all the materials and human resources to facilitate its work and to increase its profitability and efficiency., AN ELECTRONIC JOURNAL AT THE SERVICE OF SCIENTIFIC RESEARCH AND SUSTAINABLE DEVELOPMENT, Vol. 2, No 4 (2018)

In this paper, we address the design of distributed systems composed of peers (state-transitions systems) communicating through message exchanges. We consider choreographies as the ground formal model allowing a developer to describe and specify peers coordination as a set of conversations, i.e., all sequences of messages exchanged between the communicating peers. Proceeding this way does not require building the individual peers, nor their composition; they may be obtained by choreography projection. The correctness of the preservation of such messages exchanges by each peer obtained after projection is a key issue, known as the realizability problem. In our previous work [1], we have proposed a set of composition operators allowing designers to build realizable choreographies that are represented by conversation protocols (CPs). We rely on the correct-by-construction Event-B method to prove that each CP constructed using our operators is realizable. In this paper, we show how our approach applies and scales to a set of use cases borrowed from the literature and used by the research community. We also show that our approach allows to detect failures and failure recovery in case realizability does not hold

Two-dimensional molybdenum-disulfide (MoS2) catalysts can achieve high catalytic activity for the hydrogen evolution reaction upon appropriate modification of their surface. The intrinsic inertness of the compound's basal planes can be overcome by either increasing the number of catalytically active edge sites or by enhancing the activity of the basal planes via a controlled creation of sulfur vacancies. Here, we report a novel method of activating the MoS2 surface using swift heavy ion irradiation. The creation of nanometer-scale structures by an ion beam, in combination with the partial sulfur depletion of the basal planes, leads to a large increase of the number of low-coordinated Mo atoms, which can form bonds with adsorbing species. This results in a decreased onset potential for hydrogen evolution, as well as in a significant enhancement of the electrochemical current density by over 160% as compared to an identical but non-irradiated MoS2 surface.

Two-dimensional molybdenum-disulfide (MoS2) catlysts can achieve high catalytic activity for the hydrogen evolution reaction upon appropriate modification of their surface. The intrinsic inertness of the compound´s basal planes can be overcome by either increasing the number of catalytically active edge sites or by enhancing the activity of the basal planes via controlled creation of sulfur vacancies. Here, we report a novel method of activating the MoS2 surface in this respect using swift heavy ion irradiation. The creation of nanometer-scale structures by the ion beam, in combination with the partial sulfur depletion of the basal planes, leads to a large increase of the number of low-coordinated Mo atoms, which can form bonds with adsorbing species. This results in a decreased onset potential for hydrogen evolution, as well as in a significant enhance of the electrochemical current density by over 160% as compared to an identical but non-irradiated MoS2 surface.

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Sensitivity of the anatase and rutile phases of titanium dioxide to Swift Heavy Ion (SHI) irradiation was experimentally probed and compared with the predictions of the Coulomb explosion, analytical and inelastic thermal spike models of ion-matter interaction. Conforming to the predictions of all these models, our study indicated higher sensitivity of anatase to these ions than the rutile phase. A detailed examination however revealed that Coulomb explosion model cannot explain either the nature of variation of the interaction cross section of SHI with the energy deposited by these ions, Se to the target electrons, or the relative values of the threshold electronic energy loss, Seth of anatase and rutile. The analytical thermal spike (a-TS) model, using the available physicochemical data for this oxide, predicted that tracks cannot form either in anatase or in rutile by 297 MeV and 511 MeV Ni ions, while inelastic thermal spike (i-TS) model predicted formation of ion tracks by 297 MeV Ni ions and their absence with 511 MeV Ni ions in both anatase and rutile. Our observation agreed with the predictions of i-TS model albeit with a difference in the radius of the tracks. In addition, we observed halo of defect ridden crystalline region of much larger radius around the ion track. Interestingly, the radius of the halo scales with the velocity of the ions, which is opposite to the conventionally observed velocity effect.