Polyvinylidenefluoride/Poly(styrene-butadiene-styrene)/Silver Nanoparticle-grafted-Acid Chloride Functional MWCNTs-Based Nanocomposites: Preparation and Properties

A new type of nanofiltration membranes was synthesized using solution blending polyvinylidine fluoride (PVDF) and poly(styrene-butadiene-styrene) with acid chloride-modified multi-walled carbon nanotubes (MWNTs-COCl) and acid chloride-modified nanotbes-grafted-silver nanoparticles (MWNTs-COCl-Ag). SEM of PVDF/SBS-MWCNTs-COCl-Ag nanocomposite membranes showed polymer-coated Ag particles grafted on the surface. Tensile testing depicted the enhanced mechanical stability of PVDF/SBS-MWCNTs-COCl-Ag membranes around 18.8–22.4 MPa relative to PVDF/SBS-MWCNTs-COCl (10.1–13.3 MPa). 0.1 wt.% MWCNTs-COCl-Ag also enhanced the water permeability of membrane. Moreover, acid chloride-modified MWCNTs and Ag nanoparticles enhanced thermal properties to T₀ of 358°C, T₁₀ of 476°C and T_max around 599°C.     

CA 15-3 and bone scintigraphy in the follow-up of breast cancer

Twenty nine patients with blunt liver trauma were recorded in the Central Hospital of Yaounde between 1986 and 1996. The average age was 23.4 years, with the 20 to 25 and 5 to 15 age groups being the most affected. The most characteristical clinical presentation was hemoperitoneum with shock. Twenty-three patients were operated (18 in emergency and 5 secondary). While 6 patients benefited from non operative treatment due to their stable hemodynamic state. Exploration of lesions revealed 16 grade I and grade II, 8 grade III and 5 grade IV and V lesions. The operation was a simple suture in 13 cases, selective ligature of hepatic artery in 2 cases and 2 tamponades while in 4 cases the treatment was inactive. The bleeding could not be controlled in 2 cases. Peri-operative mortality was 17.39% and morbidity 21.74%, made up mainly of parietal sepsis. In our practice, blunt liver trauma are generally benign and treatment should be conservative.     

In vitro availability of minerals of some tropical and citrus fruits as influenced by antinutritional factors

Four tropical fruits and three citrus fruits were analyzed for moisture, ash, antinutritional factors (phytate, oxalate, and polyphenols) contents, and total and available minerals. Moisture contents ranged from 6.0 to 83.17% for tropical fruits while that of citrus fruits ranged from 88.20 to 89.50%. Ash contents ranged from 2.56 to 4.50% and from 3.83 to 4.83%, for tropical and citrus fruits, respectively. All fruits contained no oxalate while phytate and polyphenols ranged from 48.1 to 134.1 mg/ 100 g and from 0.115 to 0.34%, respectively. For all fruits major minerals contents ranged from 7.7 to 433.3 while trace ones ranged from 0.116 to 1.91 mg/100 g. In vitro availabilities of major minerals (% of total) varied from 11.1 to 86.2% while for minor ones it ranged from 13 to 72.5%.     

Electronic structure,optical and dielectric constant of compounds Indium-based: InAlP2, and InGaP2 in its chalcopyrite,CuPt and CuAu-I structures

First principles calculations within the density functional theory framework were carried out to calculate electronic structures and dielectric constant predictions of InGaP₂ and InAlP₂ compounds. We use three arrangements of these compounds: CuAu-I, CuPt and chalcopyrite ones. Different approximations have been dealt with in order to predict valuable bands gaps energy using DFT calculations. Electronics structure results are promising, due to the good agreement with a number of observable physical-chemistry properties. On the other hand, electron localization function and atom in molecule formalisms have been done to give more insight on the bonding properties. Capabilities that exhibit the InAlP₂ in its CuAu-I structure, such as the anisotropy and second harmonic generation, make it promising for an intensive optoelectronic application.     

Optimization of cyclopropane fatty acids production in Yarrowia lipolytica

Cyclopropane fatty acids, which can be simply converted to methylated fatty acids, are good unusual fatty acid candidates for long-term resistance to oxidization and low-temperature fluidity useful for oleochemistry and biofuels. Cyclopropane fatty acids are present in low amounts in plants or bacteria. In order to develop a process for large-scale biolipid production, we expressed 10 cyclopropane fatty acid synthases from various organisms in the oleaginous yeast Yarrowia lipolytica, a model yeast for lipid metabolism and naturally capable of producing large amounts of lipids. The Escherichia coli cyclopropane fatty acid synthase expression in Y. lipolytica allows the production of two classes of cyclopropane fatty acids, a C17:0 cyclopropanated form and a C19:0 cyclopropanated form, whereas others produce only the C17:0 form. Expression optimization and fed-batch fermentation set-up enable us to reach a specific productivity of 0.032 g·L⁻¹·hr⁻¹ with a genetically modified strain containing cyclopropane fatty acid up to 45% of the total lipid content corresponding to a titre of 2.3 ± 0.2 g/L and a yield of 56.2 ± 4.4 mg/g.     

Extending hybrid approach to secure Trivial File Transfer Protocol in M2M communication: a comparative analysis

Telecommunication Systems - Embedded Machine-to-Machine (M2M) is one of the hottest research topics in recent industrial Internet of Things. In order to serve the communication to effectively...     

Anti‐inflammatory and anticancer activities of water‐soluble peptide extracts of buffalo and cow milk Cheddar cheeses

This article aimed to assess the anti‐inflammatory and anticancer potential of water‐soluble peptide (WSP) extracts from buffalo and cow milk Cheddar cheeses. Anti‐inflammatory activity was evaluated on the basis of nitric oxide (NO) production in lipopolysaccharide‐stimulated macrophage (RAW‐264.7) cells. A cell viability assay, cell cycle arrest and apoptosis were performed to explore anticancer activity in a colon cancer model (HT‐29). The WSP extracts of both Cheddar cheeses effectively inhibited NO production in activated macrophages. Maximum growth inhibition was observed in the HT‐29 cells at concentrations of 400 and 500 μg/mL. A significant increase in cell population at G₀/G₁ phase of the cell cycle was observed. Moreover, the WSP extracts also induced extensive apoptosis in colon cancer cells.     

Thermogravimetric analysis of some chemically modified celluloses

Thermal degradation of carboxymethylcellulose, cellulose acetate, grafted wood pulp, and viscose rayon have been studied using thermogravimetric analysis and differential thermal analysis. The values of rate constant K and the activation energy E were calculated from the kinetic of weight loss using the theory of the first-order reaction. The activation energy of grafted cellulose and viscose rayon was > cellulose acetate > carboxymethylcellulose.