Spectroscopic properties of Yb in NaYbP2O7 diphosphate single crystals

Yb³⁺ absorption and fluorescent emissions were investigated for NaYbP₂O₇ diphosphate single crystals. The interpretation of electronic energy level positions has been done by using the comparison of absorption and emission spectra with those of vibronic sideband energy positions from Raman and IR absorption spectroscopies. The Yb³⁺ energy levels scheme in this host was drawn. The decay time for infrared Yb³⁺ (⁵F_5/2 excited state) fluorescence was in the range of 1–2 ms. The interest feature is leading to broad emission band at room temperature from 940 nm to 1100 nm, which seems of high interest for ultra-short laser pulse production.     

Advances in Imaging of Inflammation,Fibrosis, and Cancer in the Gastrointestinal Tract

Gastrointestinal disease is prevalent and broad, manifesting itself in a variety of ways, including inflammation, fibrosis, infection, and cancer. However, historically, diagnostic technologies have exhibited limitations, especially with regard to diagnostic uncertainty. Despite development of newly emerging technologies such as optoacoustic imaging, many recent advancements have focused on improving upon pre-existing modalities such as ultrasound, computed tomography, magnetic resonance imaging, and endoscopy. These advancements include utilization of machine learning models, biomarkers, new technological applications such as diffusion weighted imaging, and new techniques such as transrectal ultrasound. This review discusses assessment of disease processes using imaging strategies for the detection and monitoring of inflammation, fibrosis, and cancer in the context of gastrointestinal disease. Specifically, we include ulcerative colitis, Crohn’s disease, diverticulitis, celiac disease, graft vs. host disease, intestinal fibrosis, colorectal stricture, gastric cancer, and colorectal cancer. We address some of the most recent and promising advancements for improvement of gastrointestinal imaging, including unique discussions of such advancements with regard to imaging of fibrosis and differentiation between similar disease processes.     

Locations Effects on the Quality of Chemlal and Azeradj Olives Grown in Algeria

This work aimed to investigate the combined effect of harvest time and crop altitude on the fruit and oil quality of two autochthonous Algerian olive cultivars, Chemlal and Azeradj. Fruit morphological characteristics, oil quality parameters, fatty acids and triacylglycerols composition, pigments, tocopherols and oxidative stability were determined. Olives were harvested at four different ripening stages in orchards located at 110, 320 and 490 m altitude, in the olive-growing region of Kabylia, northern Algeria. Results showed a good discrimination between varieties, which were characterized by specific triacylglycerols and fatty acids profile. Different chemometric analyses carried out on the oil data highlighted the strong influence of variety in relation to the factors studied. Moreover, Principal Component Analysis performed on both fatty acids and triacylglycerols profile allowed correlating the distinct composition with the different varietal sensitivities to changes in crop attitude and ripening stage. Tocopherols showed a remarkable decrease with the ripening progress. Oxidative stability was positively correlated with variations in tocopherols and monounsaturated fatty acids during maturation and altitude changes.     

Percutaneous Absorption of Metopimazine and Effect of Cyclodextrins

Metopimazine (MPZ) is used to prevent emesis during chemotherapies. A transdermal delivery system of MPZ may present a great advantage in patients to improve compliance. Hydroxypropyl β cyclodextrin (HPβCD) and partially methylated β cyclodextrin (PMβCD) were tested to enhance the percutaneous absorption of MPZ through pig skin using Franz's cells. The MPZ hydrochloride flux was low with 0.176 ± 0.054 μg/h/cm² and no flux was detected with a suspension of MPZ (base). The used characterization analyses demonstrated the formation of an inclusion complex with cyclodextrin and this complex improved percutaneous absorption of MPZ. Flux was increased to 0.240 ± 0.032 μg/h/cm² and 0.566 ± 0.057 μg/h/cm² for HPβCD and PMβCD, respectively, with a concentration of 20%. This study has shown that HPβCD and PMβCD improved the percutaneous penetration of MPZ. Cyclodextrin complexes increased MPZ bioavailability at the skin surface and PMβCD was also able to extract cutaneous fatty acids.     

Solubility and Dissolution Rate of Progesterone-Cyclodextrin-Polymer Systems

ABSTRACT

This contribution focused on the solubility improvement of the poorly water-soluble steroid hormone progesterone which, in its natural state, presents a reduced oral bioavailability. In the first part of this study, two simple, reproducible methods that were candidates for use in the preparation of inclusion complexes with cyclodextrins were investigated. Solubility capacities of the progesterone complex with hydroxypropyl-β-CD (HPβ-CD), hydoxypropyl-γ-CD (HPγ-CD), permethyl-β-CD (PMβ-CD), and sulfobutylether-β-CD (SBEβ-CD), prepared by the freeze-drying and precipitation methods, were evaluated by Higuchi phase solubility studies. The results showed that HPβ-CD and PMβ-CD were the most efficient among the four cyclodextrins for the solubilization of progesterone, with the highest apparent stability constants. Therefore, dissolution studies were conducted on these latest progesterone/cyclodextrin complexes and physical mixtures. Two additional natural cyclodextrins, β-CD and γ-CD, were taken as references. Hence, the influence of more highly soluble derivatives of β‐CD (HPβ-CD, PMβ-CD) on the progesterone dissolution rate, in comparison to pristine β-CD, alongside an increase in the cavity width for γ-CD versus β-CD, were investigated. The dissolution kinetics of progesterone dissolved from HPβ-CD, PMβ-CD, and γ-CD revealed higher constant rates in comparison to β-CD. Therefore, the aim of the second part of this study was to investigate the possibility of improving the dissolution rate of progesterone/β-CD binary systems upon formation of ternary complexes with the hydrophilic polymer, PEG 6000, as β-CD had the smallest progesterone solubility and dissolution capacity among the four cyclodextrins studied (β‐CD, HPβ-CD, HPγ-CD and PMβ-CD). The results indicated that dissolution constant rates were considerably enhanced for the 5% and 10% progesterone/β-CD complexes in PEG 6000.

The interaction of progesterone with the cyclodextrins of interest on the form of the binary physical mixtures, complexes, or ternary complexes were investigated by differential scanning calorimetry (DSC) and Fourier transformed-infrared spectroscopy (FT-IR). The results proved that progesterone was diffused into the cyclodextrin cavity, replacing the water molecules and, in case of ternary systems, that the progesterone β-cyclodextrin was well dispersed into PEG, thus improving progesterone bioavailability for subsequent oral delivery in the same way as derivatized cyclodextrins. The present work proves that ternary complexes are promising systems for drug encapsulation.     

Retention and swelling properties of a calcareous soil during leaching by zinc solutions

The paper presents the results of leaching tests carried out on compacted calcareous clay samples using water and zinc solutions as permeants. Sequential selective extraction was used to evaluate the contribution of the different soil constituents to zinc retention. The retention and swelling properties of the soil under the different conditions were related to its porosity by means of mercury intrusion tests. During the leaching tests, the swelling of the samples varies from 27% in the case of water to 16% and 21% in the case of zinc solutions with concentrations of 2.97 and 297 g/l, respectively. The quantity of zinc retained by the soil is derived from two methods: selective sequential extraction (SSE) and acid digestion. The results from SSE show that the total quantities of absorbed zinc are equal to 76.7 and 27.2 mg/g of soil for the samples saturated with zinc at the concentrations of 2.97 and 297 g/l, respectively. This method shows that carbonate plays a significant role in the retention process through two main mechanisms: (i) the formation of precipitates of zinc carbonates, oxides and hydroxides at the lowest zinc concentration and (ii) calcite dissolution at the highest zinc concentration. Acid digestion confirms the value of the total quantity of absorbed zinc, with a relative difference of 8% with SSE. Mercury intrusion porosimetry (MIP) shows that wetting the sample with water or zinc solutions results in different pore distributions. Compared to the initial state, the pore volume of the samples increases during hydration with water or with zinc solutions. In the initial state, the sample is characterised by pores located at 10 and 0.7 μm. When the sample is saturated with water, the inter-aggregate pores increase to 30 μm and the interparticular pores, to 1 μm. When the sample is hydrated with the 2.97 g/l zinc solution, the increase of the pore size (to 20 μm) only concerns the inter-aggregate pores but is slightly lower than in the case of water. When the sample is hydrated with the 297 g/l zinc solution, the interparticular pores disappear and only an inter-aggregate pore at 20 μm is observed.The combination of the mercury intrusion and selective sequential extraction (SSE) results suggests that, for the sample saturated with the 2.97 g/l solution, the formation of precipitates leads to the obstruction of the pores, the reduction of the accessible porosity and a decrease in the swelling properties. On the other hand, carbonate dissolution leads to a widening of the pores and an increase in the accessible pore volume which is responsible for the increase in the swelling properties.     

Effects of high pressure homogenisation of raw bovine milk on alkaline phosphatase and microbial inactivation. A comparison with continuous short-time thermal treatments

Raw whole milk of high microbial quality (58 degrees C), but markedly decreased above 200 MPa when Tin=24 degrees C (T2>60 degrees C). In contrast to inactivation induced by continuous short-time thermal treatments, ALP inactivation induced by HP homogenisation was clearly due to mechanical forces (shear, cavitation and/or impact) in the HP valve and not to the short (<1 s) residence time at temperature T2 in the same valve. Inactivation of the three exogenous microorganisms led to similar conclusions. Homogenisation at 250 MPa or 300 MPa (Tin=24 degrees C) induced a 2-3 log cycle reduction of the total endogenous milk flora and a 1.5-1.8 log cycle reduction of inoculated List. innocua. Higher reduction ratios (2-4 log cycles) were obtained for the two other microorganisms. The highest levels of ALP inactivation corresponded to the highest extents of microbial reduction. Running the milk twice or three times through the homogeniser (recycling), keeping temperature T1 approximately 29 degrees C and pressure=200 MPa, increased homogenisation efficiency.     

Prevalence, quantification and antimicrobial resistance of Campylobacter spp. on chicken neck-skins at points of slaughter in 5 major cities located on 4 continents

Quantitative data on Campylobacter contamination of food are lacking, notably in developing countries. We assessed Campylobacter contamination of chicken neck-skins at points of slaughter in 5 major cities in Africa (Dakar in Senegal, Yaounde in Cameroon), Oceania (Noumea in New Caledonia), the Indian Ocean (Antananarivo in Madagascar) and Asia (Ho Chi Minh City (HCMC) in Vietnam. One hundred and fifty slaughtered chickens were collected in each of the 5 major cities from semi-industrial abattoirs or markets (direct slaughter by the seller), and 65.5% (491/750) were found to be Campylobacter-positive. Two cities, Yaounde and Noumea, demonstrated high prevalence Campylobacter detection rates (92.7% and 96.7% respectively) in contrast with HCMC (15.3%). Four species were identified among 633 isolates, namely C. jejuni (48.3%), C. coli (37.3%), C. lari (11.7%) and C. upsaliensis (1%). HCMC was the only city with C. lari isolation as was Antananarivo for C. upsaliensis. C. coli was highly prevalent only in Yaounde (69.5%). Among the 491 samples positive in Campylobacter detection, 329 were also positive with the enumeration method. The number of Campylobacter colony-forming units (CFU) per gram of neck-skin in samples positive in enumeration was high (mean of the log(10): 3.2 log(10) CFU/g, arithmetic mean: 7900CFU/g). All the cities showed close enumeration means except HCMC with a 1.81 log(10) CFU/g mean for positive samples. Semi-industrial abattoir was linked to a significant lower count of Campylobacter contamination than direct slaughter by the seller (p=0.006). On 546 isolates (546/633, 86.3%) tested for antibiotic susceptibility, resistance to erythromycin, ampicillin and ciprofloxacin was observed for respectively 11%, 19% and 50%. HCMC was the city where antibiotic resistant rates were the highest (95%, p=0.014). Considering the 329 positive chickens in Campylobacter enumeration, the mean number of resistant isolates to at least 2 different antibiotic families (19.8%), may be estimated ca. 1500CFU/g; the corresponding mean of the log(10) would be 2.5 log(10)CFU/g. As chickens are sold at slaughter and brought directly at home to be cooked, these data suggest a high probability of cross-contamination. A substantial proportion of isolates are drug-resistant, which could lead to potential public health issues. Health authorities should consider measures to reduce Campylobacter contamination of chicken during farming and at slaughter, and to provide appropriate food hygiene education. Further studies are needed in particular to investigate food-handling practices in domestic kitchens.     

High-performance glucose sensor based on glucose oxidase encapsulated in new synthesized platinum nanoparticles supported on carbon Vulcan/Nafion composite deposited on glassy carbon

In this study we synthesized Pt nanoparticles supported on carbon Vulcan (Pt/C), a cheap and high surface area carbon. Compared to the commercialized Pt/C, which showed a moderate activity towards the oxidation of H₂O₂ and a high catalytic activity to the interferences specially AP; the synthesized Pt/C illustrated a high activity towards the oxidation of H₂O₂ and negligible response towards the oxidation of the interferences at high applied potentials (>0.6 V). This difference in the catalytic behavior was attributed to the homogenous distribution of the synthesized Pt nanoparticles in the supporting carbon Vulcan as well as, to their relatively bigger size (8-9 nm) compared to (1-2 nm) estimated for the commercialized Pt/C. This particular and interesting behavior of the synthesized Pt/C was used to encapsulate glucose oxidase along with a small amount of Nafion for the manufacturing of a glucose sensor. The resulting glucose sensor has a high sensitivity of 1.25 μA/mM mm², which compares very well with other glucose sensors based on precious metal nanoparticles and carbon nanotubes, an extended linear range up to 45 mM without using any outer polymer layer, low interference from endogenous species, short response time (<5 s), was stable for at least 1 month and, found to be dependable for glucose determination in human serum.     

Nonlinear output control scheme for general decay synchronization of delayed neural networks with inertial term

This study is mainly concerned with the general decay synchronization (GDS) problem of a class of inertial neural networks (INNs) with time‐varying delay. First, unlike the methods used in previous relevant literature where both of the master and slave systems were transferred into the first‐order differential equations, only error dynamical system is transferred into the reduced‐order differential equation. Then, by designing a novel nonlinear output feedback controller and constructing suitable Lyapunov functionals, some simple and useful sufficient conditions ensuring the GDS of considered INNs are established via employing useful analysis techniques and linear matrix inequality approach. In addition, two examples are presented to show the effectiveness of the established theoretical results.