Improved loquat (Eriobotrya japonica Lindl.) cultivars: Variation of phenolics and antioxidative potential

Leaves and fruits (peel and flesh) of six improved cultivars (‘Mizuho’, ‘Néctar de Cristal’, ‘Mizauto’, ‘Mizumo’, ‘Centenária’ and ‘NE-3’) of loquat (Eriobotrya japonica Lindl.) were studied for their phenolic composition and antioxidant capacity. The analysis by HPLC-DAD-ESI-MS/MS allowed the identification of 18 compounds (8 hydroxycinnamic acid derivatives and 10 flavonoid glycosides). The quantification of the identified compounds revealed distinct profiles amongst the three analysed materials. Loquat leaves exhibited the lowest amounts of phenolics. 3- And 5-caffeoylquinic, and 5-feruloylquinic acids were the major compounds. Generally, ‘Mizauto’ cultivar presented the highest phenolic content. All loquat materials exhibited DDPH scavenging capacity, in a concentration-dependent manner, the leaves being the most active one. This effect seems to be related to the flavonoid content.     

Mast Cell Cytokines in Acute and Chronic Gingival Tissue Inflammation: Role of IL-33 and IL-37

Much evidence suggests autoimmunity in the etiopathogenesis of periodontal disease. In fact, in periodontitis, there is antibody production against collagen, DNA, and IgG, as well as increased IgA expression, T cell dysfunction, high expression of class II MHC molecules on the surface of gingival epithelial cells in inflamed tissues, activation of NK cells, and the generation of antibodies against the azurophil granules of polymorphonuclear leukocytes. In general, direct activation of autoreactive immune cells and production of TNF can activate neutrophils to release pro-inflammatory enzymes with tissue damage in the gingiva. Gingival inflammation and, in the most serious cases, periodontitis, are mainly due to the dysbiosis of the commensal oral microbiota that triggers the immune system. This inflammatory pathological state can affect the periodontal ligament, bone, and the entire gingival tissue. Oral tolerance can be abrogated by some cytokines produced by epithelial cells and activated immune cells, including mast cells (MCs). Periodontal cells and inflammatory–immune cells, including mast cells (MCs), produce cytokines and chemokines, mediating local inflammation of the gingival, along with destruction of the periodontal ligament and alveolar bone. Immune-cell activation and recruitment can be induced by inflammatory cytokines, such as IL-1, TNF, IL-33, and bacterial products, including lipopolysaccharide (LPS). IL-1 and IL-33 are pleiotropic cytokines from members of the IL-1 family, which mediate inflammation of MCs and contribute to many key features of periodontitis and other inflammatory disorders. IL-33 activates several immune cells, including lymphocytes, Th2 cells, and MCs in both innate and acquired immunological diseases. The classic therapies for periodontitis include non-surgical periodontal treatment, surgery, antibiotics, anti-inflammatory drugs, and surgery, which have been only partially effective. Recently, a natural cytokine, IL-37, a member of the IL-1 family and a suppressor of IL-1b, has received considerable attention for the treatment of inflammatory diseases. In this article, we report that IL-37 may be an important and effective therapeutic cytokine that may inhibit periodontal inflammation. The purpose of this paper is to study the relationship between MCs, IL-1, IL-33, and IL-37 inhibition in acute and chronic inflamed gingival tissue.     

Series resistance effects in thin oxide capacitor evaluation

The effects of undesired series resistance in thin oxide capacitors are studied. Thin dielectric reliability is usually evaluated by means of accelerated tests (ramped or constant voltage or current stress). It is shown that the breakdown electric field can be highly overestimated due to the series resistance associated with the test structure: the larger the resistance, the bigger the error. Moreover, breakdown detection criteria in automatic test routines become more critical. It is also demonstrated that a nonuniform stress is applied to the dielectric whenever the series resistance is position-dependent, as it usually is. Erroneous breakdown-related defect distributions could be inferred as a consequence of neglecting the series resistance effect. It is therefore suggested that workers pay much attention to the test structure layout definition in order to minimize these problems     

Methods of isolation and identification of volatile compounds in lipids

Techniques are described for the collection, separation and identification of the volatile compounds produced in lipids by oxidation or irradiation. Methods employed are high vacuum distillation followed by wide range programmed temperature gas chromatography and rapid scanning mass spectrometry. Efficacy of the methods is discussed.     

Basic Evaluation of the Catalytic Pattern of the CuCeO x System in the Wet Oxidation of Phenol with Oxygen

The working mechanism of a ceria-supported Cu (Cu_at:Ce_at = 1:10) system in the Catalytic Wet Oxidation (CWO) of phenol with O₂ (T_R, 130–170 °C; P_O2, 7 atm) has been thoroughly assessed. Basic relationships amongst pH, extent of leaching and rate of phenol and TOC conversion prove the major contribution of a homogeneous catalytic path by Cu ions on the peculiar CWO pattern of supported copper catalyst. In addition, gas-phase reduction/oxidation tests signal the lack of reversibility of the redox cycle of the CuCeO_x system under typical reaction conditions.     

Comparison among structured and packed-bed reactors for the catalytic partial oxidation of CH4 at short contact times

Three types of catalyst support (foams, honeycomb monoliths with square channels and spheres with approximately equal values of specific geometric surface a_v) were examined and compared by simulation with a 1D, dynamic heterogeneous mathematical model for application to the autothermal partial oxidation of methane. Both cold start-up and steady-state behaviours were investigated.

It was found that mass and, particularly, heat transfer properties markedly affect the reactor behaviour, both at start up and at steady state. Thus, the choice of the catalyst support can lead to greatly different reactor performances. Concerning the reactor start-up, simulations revealed that better interphase heat transport properties and lower bed heat capacity are useful to minimize the total start-up time; on the other hand, more favourable transport properties reduce the maximum flow rate which allows to achieve and maintain an ignited steady state. At steady state, oxygen conversion is strictly governed by interphase mass transfer, while methane conversion depends on a more complex, mixed chemical-diffusional regime.     

Surface characterization of Ba-β-alumina

The surface properties of a Ba-β-alumina sample (Ba ∶ Al ratio 1∶ 12) very stable to sintering (15 m²/g after calcination at 1670 K for 10 h) have been investigated by FT-IR spectroscopy of adsorbed probe molecules (water, pyridine and CO₂) and by measuring the isoelectric point. The surface has a medium-strong basic character, justified by the preferential exposition of Ba-O-containing “mirror planes”, parallel to 0001 planes, on the surface of plate-like particles. This behavior has been associated to the resistance to sintering, typical of this material, possibly originated by the difficulty of the very big Ba²⁺ ions to migrate into the spinel-type alumina blocks. This should imply the blocking of the crystal growth along the crystallographicc axis.     

Effect of hydrogen sulphide on the deactivation of alumina-supported ruthenium methanation catalysts

The deactivation of a 0.5% ruthenium-alumina catalyst for the methanation reaction has been studied at 250 and 400 °C in the absence and presence of small concentrations of hydrogen sulphide (H₂S). The adequacy of a suggested mechanistic model for the methanation reaction has been confirmed and the model has been applied to the deactivation in the absence of H₂S, which is significantly improved with respect to an empirical methanation rate equation. The effect of the presence of 10 mg dm^?3 H₂S in the reactant stream on the catalyst deactivation rate has also been investigated.