Complexes of Zn(II)–Triazoles with CO2 and H2O: Structures, Energetics, and Applications

Using a first-principle methodology, we investigate the stable structures of the nonreactive and reactive clusters formed between Zn2+–triazoles ([Zn2+-Tz]) clusters and CO2 and/or H2O. In sum, we characterized two modes of bonding of [Zn2+-Tz] with CO2/H2O: the interaction is established through (i) a covalent bond between Zn2+ of [Zn2+-Tz] and oxygen atoms of CO2 or H2O and (ii) hydrogen bonds through N–H or C–H of [Zn2+-Tz] and oxygen atoms of H2O or CO2, N–H···O. We also identified intramolecular proton transfer processes induced by complexation. Indeed, water drastically changes the shape of the energy profiles of the tautomeric phenomena through strong lowering of the potential barriers to tautomerism. The comparison to [Zn2+-Im] subunits formed with Zn2+ and imidazole shows that the efficiency of Tz-based compounds for CO2 capture and uptake is due to the incorporation of more accessible nitrogen donor sites in Tzs compared to imidazoles. Since [Zn2+-Tz] clusters are subunits of an organometallic nanoporous materials and Zn–proteins, our data are useful for deriving force fields for macromolecular simulations of these materials. Our work also suggests the consideration of traces of water to better model the CO2 sequestration and reactivity on macromolecular entities such as pores or active sites.This is the peer-reviewed version of the article: J. Phys. Chem. A 2019, 123, 26, 5555-5565, [https://doi.org/10.1021/acs.jpca.9b03228]Published version: [http://cer.ihtm.bg.ac.rs/handle/123456789/3270

Ostéchondromatose synoviale de l’articulation carpo-métacarpienne du pouce chez une patiente atteinte d’un lupus érythémateux systémique

L'ostéchondromatose synoviale est une métaplasie du tissu synovial. Elle engendre de petites masses  cartilagineuses qui font saillie à la face interne de la synoviale, puis, se pédiculisent et enfin s'en détachent en développant des chondromes libres. On en distingue deux formes d'ostéchondromatose , la forme primitive, qui est rare, et la forme secondaire plus fréquente dont l'origine est généralement l'arthrose. Nous rapportons un cas d'ostéchondromatose synoviale de l'articulation carpo-métacarpienne du pouce chez une patiente  atteinte d'un lupus érythémateux systémique.Key words: Ostéochondromatose, lupus, arthros

Pyogenic brain abscess in children: a Tunisian multi-center experience

Background: Brain abscess (BA) is an uncommon intracranial suppurative infectious disease, especially in children. Treatment involves surgery and prolonged courses of antibiotics.Objectives: Our study aimed to describe clinical characteristics of children with BA treated in middle Tunisian health centers.Methods: A retrospective study lasting 19 years (1995-2014) was conducted in Tunisia middle region. Forty one children having radiologic abnormalities suggestive of BA and confirmed per operative lesions were included. Mycobacterial, parasitic or fungal abscesses were excluded. Medical records were analyzed for age, gender, presenting symptoms, predisposing factors, imaging, microbiology results, treatment and outcome.Results: The mean age was 4.9 years. The most common clinical presentations were intracranial hypertension symptoms (87%). BA was diagnosed in 95.1% on the basis of cranial imaging. The majority of abscesses was supra-tentorial (92.6%). The most frequent etiology was loco-regional infections (63.4%). No predisposing factor was found in 17%. Intravenous antibiotics were given in all cases with surgical drainage in 63.4%,. Causative organisms were identified in 53.7%. The mortality rate was 24.3%. Age less than 2 years was the only statistically significant prognostic factor identified.Conclusion: Our study confirmed the severity of this pathology and underlined the importance of early diagnosis and management.Keywords: Pyogenic brain abscess, children, Tunisia

Effects of Irrigation with Treated Wastewater on Root and Fruit Mineral Elements of Chemlali Olive Cultivar

Twenty-year-old "Chemlali" olive trees trained to vase and rainfed were investigated in either "on" (2004) or "off " (2003) year. A randomized block design with three blocks and three treatments was used and each experimental plot consisted of nine olive trees. Three treatments were applied: (1) rainfed conditions (RF, used as control treatment); (2) irrigation with well water (WW); and (3) irrigation with treated wastewater (TWW). Irrigation with TWW led to a significant increase of root N, P, Ca, Zn, Mn, Na, and Cl concentrations, in particular in the on-year. Data showed significant differences, between the two years, for the concentration of the mineral elements in the roots, with general lower values in the on-year, probably as a consequence of nutrients movement upward in the tree. Fruit N, P, K, Zn, Mn, and Cl contents were significantly higher in TWW irrigated trees with respect to both RF and WW trees, whereas similar values for Ca, Mg, Na, and Cl contents were measured for WW and TWW irrigated trees. The irrigation with TWW allowed to reuse problematic waters and to save nutrients inputs in the olive orchard thus moving towards a more sustainable management of olive orchards in countries where water is the major limiting factor for agriculture

Choledochoduodenal fistula due to peptic duodenal ulcer diagnosed by X-barium meal study: interest of medical treatment

Peptic ulcer complication has decreased over le last years. Spontaneous bilio-digestive fistulas, in the absence of primary biliary disease, remain a very unusual complication of the upper digestive tract. The choledochoduodenal fistula is an extremely rare entity which can be caused by a duodenal peptic ulcer. It appears with the symptoms of peptic ulcer disease. They are diagnosed incidentally on radiological exams. It was suspected after finding pneumobilia on abdominal ultrasound and confirmed by X-barium meals study. The purpose of this observation is to report the case of a patient presenting a choledochoduodenal fistula diagnosed by X-barium meal to underline the importance of this radiological exam to diagnose this disease and to insist on the conservative treatment for choledochoduodenal fistula caused by a duodenal peptic ulcer. The prognosis of patients treated medically is good, although the fistula can remain asymptomatic. Angiocholitis and biliary sequelae remain rare and do not warrant prophylactic surgical treatment

Virtual water balance estimation in an irrigated area in North-eastern Tunisia

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Contribution of virtual water to improving water security in Tunisia: a case study of wheat and olive growing farms in Zaghouan region

Virtual water represents all freshwater used in the process of producing a commodity. In the case of agricultural products, many studies have focused on quantifying virtual water flows through international trade products. The concept of virtual water commercialization should be carefully studied as a potential solution for water scarcity, especially in countries facing risks of water shortage in a few years such as in Tunisia. The main idea of this paper is to optimize water use, by the mean of estimation of virtual water in exported crops which have high water consumption. We also analyze the crops that are imported and therefore, might contribute to save water. Commonly exported and imported crops are widely cultivated in the region of Zaghouan characterized by diversity of agricultural products. That’s why it could represent a good case study from Tunisia. In this study we especially focus on olive oil which is one of the most strategic exported products in Tunisia and on wheat as main imported product. We attempt to create technical and economic data sheets through monitoring about 40 farmers in this region. These sheets are not only to estimate the gross margin but also to calculate water demand for each crop allowing the estimation of virtual water. We found out that Tunisia may saves 1.13 m3 of water per kilogram of wheat if we import it instead of producing it domestically. In the case of olive trees, for an average yield of 2339 kg per hectare we exports 2.10 m3 of virtual water for every kilogram of exported olive. Results presented in this study are of essential implications for policy making regarding water use optimization and water security enhancementPublishe

Abiotic molecular oxygen production -- ionic pathway from sulphur dioxide

Molecular oxygen, O$_2$, is vital to life on Earth and possibly on other planets. Although the biogenic processes leading to its accumulation in Earth's atmosphere are well understood, its abiotic origin is still not fully established. Here, we report combined experimental and theoretical evidence for electronic-state-selective production of O$_2$ from SO$_2$, a major chemical constituent of many planetary atmospheres and one which played an important part on Earth in the Great Oxidation event. The O$_2$ production involves dissociative double ionisation of SO$_2$ leading to efficient formation of the O$_2^+$ ion which can be converted to abiotic O$_2$ by electron neutralisation. We suggest that this formation process may contribute significantly to the abundance of O$_2$ and related ions in planetary atmospheres, especially in those where CO$_2$, which can lead to O$_2$ production by different mechanisms, is not the dominant component