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Background and Objective: Osteoporosis is associated with bone microarchitecture alterations, and the depletion of estrogen during menopause is a major contributing factor to its development. The literature highlights the noteworthy role of gut microbiota in bone metabolism, particularly in the progression of osteoporosis. Periodontal disease leads to alveolar bone loss, which may be influenced by estrogen deficiency, and this mechanism is intricately associated with an imbalance in systemic microbiota. The aim of this study was to evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) and Lacticaseibacillus casei 01 (L. casei 01) administrations on an osteoporosis animal model. Materials and Methods: Thirty‐three female rats were randomly divided into three groups: control (C‐OVX), C‐OVX‐HN019 and C‐OVX‐LC01. All animals were ovariectomized. In groups C‐OVX‐HN019 and C‐OVX‐LC01, the probiotics were administered for 4 months. All animals were euthanized after 16 weeks from ovariectomy. Microtomographic, histopathological and immunohistochemical examinations were conducted on periodontal tissues, whereas histomorphometry, histopathological and immunohistochemical analyses were carried out on the intestine. The levels of estradiol were assessed in blood using an immunoenzymatic assay. The data were subjected to statistical analyses (p <.05). Results: The C‐OVX‐LC01 group exhibited a significant reduction in alveolar bone porosity and an increase in connective tissue density compared to C‐OVX (p <.05). The C‐OVX‐HN019 and C‐OVX‐LC01 groups presented reduced expression of TRAP and RANKL compared to the C‐OVX (p <.05). The C‐OVX group presented villi defects, mild neutrophil infiltration, decrease in both villous height and intestinal crypts and reduced expression of intestinal junctional epithelium markers e‐cadherin and claudin 01 compared to C‐OVX‐HN019 and C‐OVX‐LC01 (p <.05). The C‐OVX group had lower estradiol levels than C‐OVX‐HN019 and C‐OVX‐LC01 (p <.05). Conclusion: The probiotic therapy promoted a reduction in alveolar bone destruction and intestinal permeability as well as an increase in estradiol levels in ovariectomized rats. Specifically, the probiotic strain Lacticaseibacillus casei 01 exhibited greater effectiveness compared to Bifidobacterium animalis subsp. lactis HN019, indicating strain‐dependent outcomes. [ABSTRACT FROM AUTHOR]

On the finding of a population of Quickella arenaria (Potiez & Michaud, 1835) (Mollusca, Gastropoda, Succineidae) in Castilla-La Mancha (Spain) After studying many springs in the province of Cuenca (Spain) we report the finding of Quickella arenaria, a little known succinid gastropod in Spain, for the first time in Castilla–La Mancha. We discuss the threats that the population faces in this habitat and propose conservation management strategies.

The remarkable investments made by manufacturers over the last few decades have contributed to improving the performance of internal combustion engines in every aspect: lower polluting emissions, greater specific power and thermal efficiency. Despite this, on an average, about 40% of the thermal power theoretically available from the combustion of the fuel is still stored in the exhaust gases and therefore dispersed in the environment. In this work the modeling and validation of a waste heat recovery (WHR) plant will be described, combining the engine with a low temperature Organic Rankine Cycle (ORC) system, in order to investigate the feasibility of this system on board of a vehicle, analyzing the quantity of thermal power recovered and made available in the form of electrical power. The ORC plant is modeled using a 0D/1D thermo-fluid dynamic approach. Starting from experimental tests, a map-based model for the piston pump and the scroll expander has been developed. The model has been validated through the use of a vector optimization technique, exploiting a genetic algorithm (MOGA). Subsequently, this system has been coupled to a spark ignition engine for automotive applications, adapting its speed range to comply with the ORC experimental tests. To have an accurate control over the expander inlet temperature, a bypass circuit and two throttles actuated by a PI controller have been implemented. The simulations were performed by considering 18 engine points at maximum load and different rpm. An average thermal efficiency increase of the system of 2.6% was obtained by introducing the recovery plant, and wide improvement chance can be foreseen in the case of ORC full-power use.

Birnessites containing Na+ or K+ in the interlayer have been prepared following a sol-gel method, with an initial glucose/cation ratio of 1 or 1.5. The solids have been submitted to ion exchange with Li+, Mg2+, and Cu2+, and all the materials have been characterised by several physicochemical techniques (elemental chemical analysis, X-ray diffraction, FT-IR spectroscopy, thermal analysis and specific surface area assessment). Total cation exchange was not achieved in any case, although sodium is better exchanged than potassium. Exchange is larger for Li+, lower for Cu2+ and even lower for Mg2+. Ionic exchange is topotactic, and the layered structure is maintained in all cases, with an interlayer spacing close to 7 Å. The samples are stable up to 600 °C; above this temperature cryptomelane (a 2x2 tunnel structure) is formed in most of the samples containing potassium, while LiMn2O4 spinel is formed is Li was present in the birnessite.Se han preparado birnesitas con Na+ o K+ en la interlámina mediante un método sol-gel, con una relación inicial glucosa/catión de 1 y 1.5. Estas muestras se han sometido a cambio iónico con los cationes Li+, Mg2+ y Cu2, caracterizando las muestras intercambiadas por diversas técnicas (análisis químico elemental, difracción de rayos X, espectroscopía FT-IR, análisis térmico y determinación de superficie específica). En ningún caso se alcanza un cambio iónico completo de los iones sodio o potasio iniciales, aunque el sodio se intercambia en mayor medida que el potasio. El intercambio es más efectivo al incorporar el Li+, menor en el caso del Cu2+ y menos eficiente, todavía, al incorporar Mg2+. El cambio iónico se produce topotácticamente, manteniéndose en todos los casos la estructura laminar con una distancia interlaminar de, aproximadamente, 7 Å. Las muestras son estables hasta 600 ºC; a partir de esta temperatura se produce la transformación a estructura túnel 2x2 (criptomelano) en el caso de la birnesita de K y a la espinela de Li-Mn (LiMn2O4) en el caso de tener Li en la interlámina.

Chromium(III) and cobalt(II) hydrotalcite layers with carbonate or decavanadate interlayers exhibit an ordered structure in which the Cr(III) and Co(II) ions are contained in octahedral regions within the layers. The atomic ratios of the CoCrV and CoCrC cations are 1.60 and 1.86, respectively. The oxidation of Co(II) to Co(III) in CoCrC due to calcination produced amorphous materials at intermediate temperatures while high temperatures produced CoCr2O4 crystals.

The preparation of the new Mg2Al-paratungstate layered double hydroxides is presented. Its synthesis, properties and characterization are also explained in detail.

Research has been conducted on Mg,Al layered double hydroxides. The authors describe the synthesis of these compounds with [Cr(C (sub)2 O (sub)4) (sub)3] (super)3- anions in the interlayer, and they report that the prepared solids have been characterized via powder X-ray diffraction, FT-IR, thermal methods, elemental chemical analysis and nitrogen adsorption.