Microbial-Physical Synthesis of Fe and Fe3O4 Magnetic Nanoparticles Using Aspergillus niger YESM1 and Supercritical Condition of Ethanol

Magnetic Fe and Fe3O4 (magnetite) nanoparticles are successfully synthesized using Aspergillus niger YESM 1 and supercritical condition of liquids. Aspergillus niger is used for decomposition of FeSO4 and FeCl3 to FeS and Fe2O3, respectively. The produced particles are exposed to supercritical condition of ethanol for 1 hour at 300∘ C and pressure of 850 psi. The phase structure and the morphology measurements yield pure iron and major Fe3O4 spherical nanoparticles with average size of 18 and 50 nm, respectively. The crystal size amounts to 9 nm for Fe and 8 nm for Fe3O4. The magnetic properties are measured to exhibit superparamagneticand ferromagnetic-like behaviors for Fe and Fe3O4 nanoparticles, respectively. The saturation magnetization amounts to 112 and 68 emu/g for Fe and Fe3O4, respectively. The obtained results open new route for using the biophysical method for large-scale production of highly magnetic nanoparticles to be used for biomedical applications

Propriétés osmotiques et magnétiques des solutions d'hélium-3 dans l'hélium-4 superfluide

International audienceWe review in this paper recent (prior to 1978) theoretical and experimental work done at Orsay and elsewhere on 3He-4He mixtures. We start by showing that the set of thermodynamic variables (T,n,n_3,\mu_4) is a privileged set for the description of a superfluid solution and we derive basic formulae of the statistical mechanics of boson-fermion mixtures. We insert in the formalism the equation of state, assumed to be known at the start, and the fact that 3He and 4He are isotopes. This simple approach leads in the dilute 3He limit to the well-known theory of Bardeen-Baym-Pines that we summarize with its more recent developments. To go beyond this straight-forward construction, we parametrize the scattering amplitude V(p,p',q) of two scattering 3He quasi-particles with momenta p and p' to lowest order in q=p'-p, p and p'. We proceed to compute all the equilibrium properties of the mixtures. We then extract `best values'' of the model parameters from experimental results.Nous donnons, dans cet article de revue, une synthèse de travaux récents effectués à Orsay et ailleurs, tant sur le plan théorique qu'expérimental sur les mélanges d'3He dans l'4He. Nous commençons par montrer que le jeu de variables thermodynamiques (T, n, n_3, \mu_4) fournit une description privilégiée de la solution superfluide et nous rappelons quelques formules fondsmentales de la mécanique statistique des mélanges fermions-bosons. A ce formalisme, nous ajoutons la connaissance de l'équation d'état d'une part, et d'autre part le fait qu'3He et 4He sont isotopes. Cette démarche directe mène, pour les solutions diluées, à la théorie bien connue de Bardeen-Baym-Pines dont nous donnons un condensé, ainsi que de ses développements récents. Pour aller au-delà de cette construction sans complication, nous introduisons une forme paramétrée de l'amplitude de collision de deux quasi-particules 3He en interaction. Nous évaluons ensuite les propriétés thermodynamiques correspondantes. Nous extrayons ensuite les valeurs des paramètres de ce modèle des données expérimentales

Biofilm Formation by Marine Cobetia marina alex and Pseudoalteromonas spp: Development and Detection of Quorum Sensing N-Acyl Homoserine Lactones (AHLs) Molecules

Surfaces submerged in seawater are colonized by various microorganisms, resulting in the formation of heterogenic marine biofilms. This work aims to evaluate the biofilm formation by Cobetia marina alex and doing a comparative study between this promising strain with the two bacterial strains isolated previously from the Mediterranean seawater, Alexandria, Egypt. Three strains; Cobetia marina alex, Pseudoalteromonas sp. alex, and Pseudoalteromonas prydzensis alex were screened for biofilm formation using the crystal violet (CV) quantification method in a single culture. The values of biofilm formed were OD600= 3.0, 2.7, and 2.6, respectively leading to their selection for further evaluation. However, factors affecting biofilm formation by C. marina alex were investigated. Biofilm formation was evaluated in single and multispecies consortia. Synergistic and antagonistic interactions proved in this work lead to the belief that these bacteria have the capability to produce some interesting signal molecules N-acyl Homoserine Lactones (AHLs

Characterization of Biofilm Forming Marine Pseudoalteromonas spp

Biofilm forming bacteria are omnipresent in the marine environment. Pseudoalteromonas is one of the largest within the γ-proteobacteria class, and a member of marine bacteria. Species of Pseudoalteromonas are generally found in association with marine eukaryotes. In this work, we present the isolation and characterization of two strains forming biofilm on rock surface and associated with marine sponge. They were identified using 16SrDNA as Pseudoalteromonas prydzensis alex, and Pseudoalteromonas sp. alex. They showed the highest titer in biofilm formation quantified using the test tube method using crystal violet

New Azacycles by One-Pot Three-Component Hantzsch-Like Synthesis of Tetra(hexa)azacyclopenta[a]anthracenes, Tetraazaindeno[5,4-b]fluorenes, and Oxatetraazacyclopenta[m]tetraphenes

Multicomponent reactions (MCRs) are envisaged as an entry point for the synthesis of heterocyclic compounds with interesting biological activities. An efficient approach to annelated tetra(hexa)azacyclopenta[a]anthracenes, tetraazaindeno[5,4-b]fluorenes, and oxatetraazacyclopenta[m]tetraphene was accomplished using a three-component reaction involving 7-amino-2-methyl-3-phenylpyrazolo[1,5-a]pyrimidin-5-one with aromatic aldehydes and the corresponding active 1,3-dicarbonyl compounds (namely, dimedone, 1,3-dimethylbarbituric acid, 1,3-indanedione, and 4-hydroxycoumarine). The reactions were conducted in glacial acetic acid at reflux for 5 h to give the desired products in good yields (62–83 %). The chemical constitutions of all new products were confirmed spectroscopically

The normal dimensions of the sella turcica in Jordanians: a study on lateral cephalograms

Background: The sella turcica is an important anatomic and radiologic entity. The dimensions of the sella turcica vary greatly in normal individuals and are influenced by genetic and local factors. The main objective of this study is to build up a normative database of the dimensions of the sella turcica in the Jordanian population. Materials and methods: For this purpose 509 computed cephalograms of 252 male and 257 female healthy Jordanians aged 10–40 years were collected and divided into two adolescent and adult age-groups for both genders. Viewbox 3 software was used to determine linear dimensions and area of the sella turcica. Results: Our results showed that the overall values for width, length, height, area, and aperture (interclinoid distance) were 8.72, 7.68, 6.25, 40.80, 3.92, and 8.67, 7.42, 6.38, 41.26, 3.68 mm (mm2) for males and females, respectively. Significant differences were found between adult male group on one hand and adolescent female group and adult female group on the other hand. Between age categories and within male and female groups, sella parameters were significantly different between adolescent and adult age-groups. Conclusions: Our data clearly confirm the classical notion of general trend of increase in parameters with age, irrespective of gender, with the area scoring the highest increase, and the height in females and length in males contributing most obviously to this trend. The aperture appears to decrease in females while it increases in males as adulthood is reached. This seems to reflect differential growth of the pituitary gland under neurohormonal effects

Comparative study between fisher anatomical subunit approximation technique and millard rotation- advancement technique in unilateral cleft lip repair

Introduction: The ideal lip repair is characterized by; the symmetrical shape of nasolabial folds and both alae of the nose with a natural-looking philtrum and Cupid’s bow in both static and dynamic states, in addition to a hidden scar.Objective: to compare between Fisher anatomical subunit approximation technique and Millard rotational advancement technique in unilateral cleft lip repair.Methods: Prospective study for 40 patients presented to Alexandria Main University hospital with unilateral cleft lip deformity between March 2019 and October 2020. Twenty patients with unilateral cleft lip deformity were repaired by Fisher anatomical subunit approximation technique, while the other twenty were repaired by Millard rotational-advancement technique. The postoperative photographs of the patients were captured and processed in computer photogrammetry software through which anthropometric parameters including (lip height, lip width, vermilion height, and alar base width) were compared between the normal side and the repaired side. In this software, each anthropometric parameter length on the normal side is taken as a control with a fixed value of (1) then the same parameter on the repaired side was measured as a ratio of this value to avoid bias. Comparison between both groups for assessment of the quality of cleft lip repair was also done based on Steffensen grading criteria.Results: Comparison between both techniques in unilateral cleft lip repair showed that there was no significant difference between them in the anthropometric measurements. While the comparison between the two groups using Steffensen grading criteria showed that Fisher’s technique surpassed Millard’s technique.Conclusion: We recommend the use of the Fisher anatomical subunit approximation technique in unilateral cleft lip repair for its superior results over the Millard rotational advancement technique

Agarase Production by Marine Pseudoalteromonas sp. MHS: Optimization, and Purification

Agar is an essential polysaccharide that has been utilized in numerous fields. Many kinds of literature have been published regarding agarolytic microorganisms’ isolation and agarases biochemical studies. In this search, a local marine agarolytic bacterium associated with marine alga Ulva lactuca surface was isolated and identified as Pseudoalteromonas sp. MHS. The agarase production was parallel to the growth of Pseudoalteromonas sp. MHS as cells displayed a lag phase (2 h), subsequently an exponential growth that prolonged till 10 h where maximum growth (OD550nm = 3.9) was achieved. The enzyme activity increased rapidly as cells increased exponentially where the maximum activity of 0.22 U/mL was achieved after 8h and remained constant till 12 h during the stationary phase of growth. Agarase production was optimized using Plackett-Burman statistical design by measuring enzyme activity as a response and the design was validated using a verification experiment; the activity of the enzyme increased from 0.22 U/mL to 0.29 U/mL. Pseudoalteromonas sp. MHS agarase was partially purified and its molecular weight (MW) was determined by SDSPAGE (15-25 kDa). Agarase showed approximately 94% of its activity at 40 °C. The enzyme stability decreased as the temperature increased; the enzyme could retain about 98, 90, 80, 75, and 60% of its activity at 20, 30, 40, 50, and 60 °C, respectively. Biomass of the red alga Pterocladia capillacea proved to be a suitable substrate for agarase production using Pseudoalteromonas sp. MHS; the enzyme activity recorded after 24 h of incubation was 0.35 U/mL compared to 0.29 U/mL from the optimized medium

Isolation and identification of a prodigiosin-like pigment producer Vibrio sp. isolate from a sea snail Thais sp

Marine bacteria associated with Mediterranean Sea snails have not been explored intensively. The aim of the study was to explore marine pigmented bacteria associated with the sea snail Thais sp. commonly found in Alexandria seashores where a red-pigmented bacterium was isolated and identified as Vibrio sp. based on phenotypic traits and 16S rRNA gene sequence analysis. Based on ultraviolet-visible (UV-vis) spectral and liquid chromatography-mass spectrometry (LC-MS) analysis, the red pigment was identified as a prodigiosin-like pigment. To our knowledge, this is the first report on the isolation of a Vibrio strain from a gastropod able to synthesize prodigiosin. Maximum production (7 mg/L) was achieved after two days in MZM cultures containing 0.5% mannitol and 2.5% soybean meal, pH 7 and statically incubated at 30 °C, using Plackett-Burman factorial design. RT-qPCR revealed that pks-1 and nrps responsible for the biosynthesis of prodigiosin and other bioactive compounds were up-regulated by the addition of sublethal concentrations of imipenem, DMSO, and the heavy metals copper oxide and chromium VI oxide. Through this work it can be concluded that marine invertebrates should be further explored for bacteria producing bioactive compounds whose synthesis can be enhanced or blocked depending on the carbon and nitrogen sources adopted in the fermentation medium. Moreover, the mRNA expression of the genes responsible for prodigiosin-like pigment production can be up-regulated through adopting sub-lethal concentrations of stress inducing compounds as well as co-cultivatio

A robust binary supramolecular organic framework (SOF) with high CO2 adsorption and selectivity

A robust binary hydrogen-bonded supramolecular organic framework (SOF-7) has been synthesized by solvothermal reaction of 1,4-bis-(4-(3,5-dicyano-2,6 dipyridyl)dihydropyridyl)benzene (1) and 5,5’-bis-(azanediyl)-oxalyl-diisophthalic acid (2). Single crystal X-ray diffraction analysis shows that SOF-7 comprises 2 and 1,4-bis-(4-(3,5-dicyano-2,6-dipyridyl)pyridyl)benzene (3), the latter formed in situ from the oxidative dehydrogenation of 1. SOF-7 shows a three-dimensional four-fold interpenetrat-ed structure with complementary O−H···N hydrogen bonds to form channels that are decorated with cyano- and amide-groups. SOF-7 exhibits excellent thermal stability and sol-vent and moisture durability, as well as permanent porosity. The activated desolvated material SOF-7a shows high CO2 sorption capacity and selectivity compared with other po-rous organic materials assembled solely through hydrogen bonding