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Since its first introduction in 2016, cold sintering process (CSP) has gained worldwide interest from the scientific community as green and innovative fabrication route due to the dramatic reduction of processing time, energy, and costs. Cold sintering resembles the geological formation of rocks where a ceramic powder is densified with the aid of a liquid phase under an intense external pressure and limited heating conditions (below 350 °C). Up to date, tens of different materials, including composites, have been successfully processed through CSP and extraordinary results in terms of densification, microstructure and final properties have been achieved. In the present review, processing features and variables, possible densification mechanisms and issues also for the realization of ceramic-based composites are explored. Advantages with respect to existing techniques are analysed and current challenges are described to lay the ground for new processing opportunities to be faced in the near future.

Background β-blockers are one of the four recommended disease-modifying classes of drugs for the treatment of heart failure with reduced ejection fraction (HFrEF). Although their efficacy and prognostic role is unquestionable in the general population of HFrEF patients, the differences in their effect in relation to sex have not been yet investigated in detail. The present study analyzed a large, real-world, Italian population of HFrEF patients aiming to highlight any prognostic difference between males and females in relation to dose and β-selectivity of the ongoing β-blocker treatment. Methods Out of the 7900 HFrEF patients included in the MECKI score registry, we retrospectively analyzed those treated with β-blockers. We investigated the prognostic role of β-selectivity, dividing the population in assuming β1/β2-receptor blockers (carvedilol) vs. β1-selective blockers (bisoprolol, nebivolol or metoprolol), according to sex, and the prognostic role of daily carvedilol-equivalent β-blocker dose in relation to sex. The primary outcome of the study was the composite of all cause mortality, urgent heart transplant and LVAD implant analyzed at 5 years, both as raw data and after correction of potential confounders. Results 6784 HFrEF patients treated with β-blockers were analyzed (1215 females, 5569 males). Patients median follow-up was 4.05 years [1.72-7.47]: 4.37 [1.6-8.13] for females and 3.99 [1.75-7.3] for males (p=ns). According to β-selectivity no prognostic differences were found in the general population, as in female or males (Fig. 1 right panel). Stratification of patients according to β-blockers equivalent dose showed significant difference among groups: mortality decreases with increasing β-blockers dose in both males and females (Fig. 1, left panel), both at baseline and after adjustment for the main confounders (LVEF, age, peakVO2, systolic pressure, hemoglobin, rest heart rate; VE/VCO2 slope, etiology. ICD, MDRD). Conclusions In a large, real-life population of chronic HFrEF patients analyzed according to sex, no prognostic differences were found between stratifying for β-selectivity. A better outcome was observed in subjects receiving a high daily dose, independently from sex.

Wood species identification and characterization of its weathering processes are crucial steps in the scientific approach of conservation of wooden cultural heritage. Many precious wooden objects of ancient Egypt are largely present in museums, nevertheless relatively little information is available concerning the nature of timber used and on their status of conservation. To address this gap, the wooden species of three relevant archaeological wood objects (statue, box, and coffin) arising from different Egyptian archaeological sites dated from the Old Kingdom (2,686-2,181 BC) to New Kingdom (1,550-1,069 BC) were deeply studied. Five hardwood and softwood species were identified belonging to Tamarix mannifera, T. gennessarensis, Ficus sycomorus, Vachellia nilotica, and Cedrus sp. Such data confirmed the recurrence of Vachellia and Tamarix among the most common timbers found in ancient Egypt. Scanning electron microscope, Fourier transform spectroscopy, and synchrotron x-ray radiation diffraction were conducted to evaluate the archaeological wood deterioration. The formation of microcracks, biological degradation patterns (fungal colonization), or chemical characterization (accumulation of salts on and in-between wooden cells) were detected. SEM micrographs showed the presence of fungal hyphae and conidial spores on the wooden cells. Significant changes in the chemical wood composition and decrease in the crystallinity index were detected.

Nanosized calcium deficient carbonated apatite was synthesized from three different natural resources, namely chicken eggshells (calcite), cuttlefish bones (aragonite) and mussel shells (aragonite/calcite). The calcium precursors were ball-milled in (NH4)2HPO4 or H3PO4 – containing aqueous medium for different times and then dried at temperatures ranging from 20 °C to 150 °C. The formation of hydroxyapatite (HA) is shown to be strongly affected by such treatment, the amount of synthesized HA increasing with temperature. Aragonite from cuttlebones and the aragonitic fraction of mussels is found to be transformed more easily with respect to the calcite from eggshells. The reaction is also favored by an acidic milling media with respect to basic one. The feasibility of the synthesis process at nearly room temperature described in the present work has interesting potentialities in the retention of the organic portions of the original biological resource in the produced nanometric inorganic compound.

Background and Aims Proteases are responsible for protein degradation during leaf senescence, allowing nutrients to be redirected to sink tissues. In a previous work, we reported that sulphur deficiency produced a delay in the leaf senescence of barley (Hordeum vulgare L.) plants, at both vegetative and reproductive stages. In this work, we analyse the effect of sulphur deficiency on the expression of several genes coding for proteases of different catalytic groups, which have been strongly associated with leaf senescence. Methods Four independent experiments were performed in order to impose low sulphur availability conditions: one of steady-state sulphur deficiency during the vegetative stage and three of sulphur starvation during vegetative and reproductive stages. Key Results Sulphur deficiency inhibited or reduced the senescence-associated induction of seven of the eight proteases analysed. Their induction, as well as senescence and phloem amino acid remobilization, could be achieved with senescence inducers such as methyl-jasmonate (a hormonal stimulus) and darkness, but with different rates of induction dependent on each gene. Sulphur deficiency also exerted an opposite effect on the expression of two cysteine-protease genes (HvSAG12 and HvLEGU) as well as on one serine-protease gene (HvSUBT) according to leaf age and plant phenological stages. All three genes were induced in green leaves but were repressed in senescent leaves of sulphur-deficient plants at the vegetative stage. At the reproductive stage, both cysteine-proteases were only repressed in senescent leaves, while the serine-protease was induced in green and senescent leaves by sulphur deficiency. Conclusions Our results highlight the relevance of adequate sulphur nutrition in order to ensure leaf senescence onset and induction of protease genes, which will consequently impact on grain protein composition and quality. In addition, our results provide evidence that leaf age, plant developmental stage and the nature of the stress modulate the sulphur responses.

Proteases play a main role in the mobilization of storage proteins during seed germination. Until today, there is little information about the involvement of serine proteases, particularly subtilases, in the germination of barley grains. The aims of the present work were to study the contribution of serine proteases to the total proteolytic activity induced during germination of barley grains and evaluate the specific involvement of subtilases in this process. Proteolytic activity assayed against azocasein in the presence of specific inhibitors, showed that serine proteases contributed between 10 and 20% of total activity along germination. Subtilase activity increased from day 1 after imbibition with a peak between days 4-5. Moreover, in vivo determination of subtilase activity in germinating grains revealed increasing activity along germination mainly localized in the seed endosperm and developing rootlets. Finally, the expression of 19 barley genes encoding subtilases was measured by real time PCR during germination. Three of the analyzed genes increased their expression along germination, five showed a transient induction, one was down-regulated, nine remained unchanged and one was not expressed. The present work demonstrates the involvement of subtilases in germination of barley grains and describes the positive association of eight subtilase genes to this process.

Plant proteolytic enzymes belonging to the S8 family of serine proteases are known as subtilases or subtilisin-like proteases. Subtilases compose the largest family of plant serine peptidases and have been associated to a wide range of physiological responses and developmental stages. We here describe a simple and fast method to reveal subtilase activity in vivo in germinating seeds of different crops. The method is based on the hydrolysis of N-Succinyl-Ala-Ala-Pro-Phe p-nitroanilide (Suc-AAPF-pNA), a synthetic peptide highly specific for subtilases, and subsequent diazotization of liberated p-nitroaniline giving an intense pink dye. The method was tested in germinating seeds of four cereals (wheat, maize, sorghum and rice). In order to verify subtilase activity in such materials, soluble extracts were prepared and analyzed by a standard protocol for in vitro measurement of Suc-AAPF-pNA degradation. Results revealed subtilase activity in vivo in all the cereal grains tested, showing strong correlation with spectrophotometric measurement of subtilase activity in soluble extracts. The present work not only describes for the first time a method to asses for subtilase activity in vivo, but also reveals the ubiquity of active subtilases during the germination of different plant species.

Due to unique osteogenic properties, tricalcium phosphate (TCP) has gained relevance in the field of bone repair. The development of novel and rapid sintering routes is of particular interest since TCP undergoes to high-temperature phase transitions and is widely employed in osteoconductive coatings on thermally-sensitive metal substrates. In the present work, TCP bioceramics was innovatively obtained by Ultrafast High-temperature Sintering (UHS). Ca-deficient hydroxyapatite nano-powder produced by mechanochemical synthesis of mussel shell-derived calcium carbonate was used to prepare the green samples by uniaxial pressing. These were introduced within a graphite felt which was rapidly heated by an electrical current flow, reaching heating rates exceeding 1200 °C min−1. Dense (> 93%) ceramics were manufactured in less than 3 min using currents between 25 and 30 A. Both β and α-TCP were detected in the sintered components with proportions depending on the applied current. Preliminary tests confirmed that the artifacts do not possess cytotoxic effects and possess mechanical properties similar to conventionally sintered materials. The overall results prove the applicability of UHS to bioceramics paving the way to new rapid processing routes for biomedical components.

Este trabalho relata experiências com jogos no ensino da matemática desenvolvidaspor acadêmicos do Curso de Licenciatura em Matemática do IFC-Campus Camboriú,bolsistas do programa de residência pedagógica (CAPES). Foram realizadasintervenções utilizando esta metodologia em uma turma do sexto ano do ensinofundamental, para trabalhar operações com números inteiros, e em uma turma dosegundo ano do ensino médio, em uma avaliação sobre o conteúdo de progressões.Observou-se que as atividades propostas pelos acadêmicos favoreceram algunsalunos, podendo-se afirmar que a prática pedagógica, mediante o uso de jogos,intervém no processo de construção do conhecimento.

Biogenic calcium carbonates naturally contain ions that can be beneficial for bone regeneration and therefore are attractive resources for the production of bioactive calcium phosphates. In the present work, cuttlefish bones, mussel shells, chicken eggshells and bioinspired amorphous calcium carbonate were used to synthesize hydroxyapatite nano-powders which were consolidated into cylindrical pellets by uniaxial pressing and sintering 800&ndash, 1100 &deg, C. Mineralogical, structural and chemical composition were studied by SEM, XRD, inductively coupled plasma/optical emission spectroscopy (ICP/OES). The results show that the phase composition of the sintered materials depends on the Ca/P molar ratio and on the specific CaCO3 source, very likely associated with the presence of some doping elements like Mg2+ in eggshell and Sr2+ in cuttlebone. Different CaCO3 sources also resulted in variable densification and sintering temperature. Preliminary in vitro tests were carried out (by the LDH assay) and they did not reveal any cytotoxic effects, while good cell adhesion and proliferation was observed at day 1, 3 and 5 after seeding through confocal microscopy. Among the different tested materials, those derived from eggshells and sintered at 900 &deg, C promoted the best cell adhesion pattern, while those from cuttlebone and amorphous calcium carbonate showed round-shaped cells and poorer cell-to-cell interconnection.

Waterlogged archaeological wood (WAW) is considered a precious material, first-hand account of past civilizations. Like any organic material, it is subjected to biodegradative action of microorganisms whose activity could be particularly fast and dangerous during the phases of excavation, storage and restoration. The present work aimed to characterize the microorganisms present in WAW during these tricky periods to evaluate the biological risk it is exposed to. The bacterial and fungal communities inhabiting woods coming from two archaeological sites (Pisa and Naples) were investigated through Next-Generation Sequencing (NGS). High-throughput sequencing of extracted DNA fragments was performed using the reversible terminator-based sequencing chemistry with the Illumina MiSeq platform. The analyses revealed that the two archaeological sites showed distinct richness and biodiversity, as expected. In all the WAWs, the bacterial community harbored mainly Proteobacteria, whereas Bacteroidetes was well represented only in Naples communities and taxa belonging to the phyla Chloroflexi only in the Pisa site. Concerning the fungal community, the two sites were dominated by different phyla: Ascomycota for Naples samples and Basidiomycota for Pisa. Interestingly, most of the identified bacterial and fungal taxa have cellulolytic or ligninolytic ability. These results provide new and useful background information concerning the composition of WAW microbiota and the threat it represents for this precious material.

Clinical multislice X-ray computed tomography (MCST) was performed on a seventeenth-century panel painting from the collection of the National Academy of San Luca Gallery in Rome. The use of MSCT allowed us to detect the numerous characteristics of the wood used, the panel construction, and its condition, leading to a complete preliminary interpretation of its structural characteristics.

Waterlogged archaeological wood comes from submerged archaeological sites (in lake, sea, river, or wetland) or from land waterlogged sites. Even if the wooden object seems to have maintained the original size and shape, the wood is more or less severely decayed because of chemical and biological factors which modify the normal ratio of cellulose and lignin in the cell wall. Drying procedures are necessary for the musealization but potentially cause severe shrinkages and collapses. The conservation practices focus not only on removing water from wood but also on substituting it with materials able to consolidate the degraded wood cell walls like polymers (e.g., PEG), sugars (e.g., lactitol), or resins (e.g., Kauramin). In the present work three different nano-scale consolidants were tested: lignin nanoparticles (LNPs) obtained form beech wood via a non-solvent method involving dialysis; bacterial nanocellulose (BC) obtained from cultures fed with agro-alimentary waste; cellulose nanocrystals (CNC) chemically extracted from native cellulose. Waterlogged archaeological wood samples of different species (oak, elm, stone pine, and silver fir) characterized by different levels of degradation were impregnated with the consolidants. The treatments efficiency was evaluated in terms of macroscopic observation of treated samples, anti-shrink efficiency (ASE) and equilibrium moisture content (EMC). The results obtained for the three consolidants showed substantial differences: LNPs and CNCs penetrated only about a millimeter inside the treated wood, while BC formed a compact layer on the surface of the cell walls throughout the thickness of the samples. In spite of successful BC penetration, physical evaluation of treatment efficiency showed that BC nanoparticles did not obtain a satisfying consolidation of the material. Based on the reported results more focused test protocols are optimized for future consolidation experiments.

Oak disks from pile dwellings of the prehistoric site of Gran Carro (lake Bolsena, Italy) were analysed in order to estimate wood degradation. Micro-morphological observations showed that the microbial decay could be mainly attributed to erosion bacteria. The most important physical properties, i.e. Maximum Water Content (MWC), Residual basal Density (RDb), and the calculation of the Lost Wood Substance (LWS) highlighted that heartwood (HW) was moderately preserved, with MWC values slightly higher or comparable to that of recent oak, whereas sapwood (SW) was very degraded. Thermogravimetric analysis (TGA) was tested as an alternative method for the chemical characterisation of archaeological wood. The TGA profiles were critically discussed taking into account the results of the physical and micro-morphological analyses. Potentialities and drawbacks of TGA were underlined.

En Argentina, se registra, durante los últimos años, un aumento en la producción lechera de cabras y de ovejas, que coincide con una tendencia a nivel mundial. En general, estas producciones pertenecen a pequeños y medianos productores que poseen numerosas dificultades para obtener un producto de calidad y en cantidad adecuada para asegurar la rentabilidad de la actividad. Sin embargo, bajo condiciones apropiadas de manejo, es una producción con mucha potencialidad, ya que la leche producida no sólo puede distribuirse como tal, sino que puede utilizarse como materia prima para elaboración de quesos y dulce de leche aumentando así el valor agregado del producto que se comercializa. Por otro lado, en los últimos años el gobierno demostró un creciente interés en esta actividad implementando políticas y créditos de financiamiento que propiciaron un fuerte impulso en el sector. La Región Centro del país (con gran aporte de la provincia de Buenos Aires), es el territorio con mayor cantidad de unidades productivas ovinas y la segunda región en cuanto a número de animales (después de la Patagonia). En el caso del caprino, si bien la provincia de Neuquén es la que registra el mayor número de existencias, el número de establecimientos en la provincia de Buenos Aires se ha incrementado en los últimos años. El mayor desarrollo de tambos ovinos y caprinos en la provincia de Buenos Aires se debe a su cercanía con los centros de comercialización, la posibilidad de ubicación de productos en el mercado interno y la actividad turística que presenta la zona, entre otros factores. Una de las problemáticas más relevantes que presentan los sistemas lecheros es lograr un adecuado número de animales para la reposición de hembras, por lo que el manejo de la crianza de los corderos y cabritos es crítico. Además, al ser la leche el producto que da el mayor ingreso económico al establecimiento, su utilización en la alimentación de las crías de pequeños rumiantes impacta negativamente en la cantidad de litros comercializados. La crianza artificial es una práctica común utilizada en muchos países, pero en Argentina, es utilizada sólo en algunos establecimientos. En general, las metodologías de crianza artificial implementadas se basan en recomendaciones entre productores sin contar con una base profesional al respecto. Por esta razón, es necesario conocer si la metodología de crianza artificial considerada tiene un impacto en la salud y crecimiento de los animales, especialmente cuando se incorporan antibióticos como herramienta productiva (ya sea para prevenir enfermedades o como promotores de crecimiento). In Argentine, since the last few years it has been recorded a rise in milk production from goats and sheep that match global tendencies. In general, these productions belong to small and medium producers who have numerous difficulties to obtain a product of quality and in an adequate amount to ensure the profitability of the activity. Despite that (with proper management conditions) the production has huge potential due to the fact that the milk produced could be used as it is or as raw material for cheese and dulce de leche, raising its commercial value. In addition, the government has shown an increasing interest in the activity coming up with new policies and financial support that gave a strong impulse to the sector. The Central Region of the country (with an important contribution of Buenos Aires province) is the territory with the highest number of productive sheep units and the second region in terms of number of animals (after Patagonia). For goats, even though Neuquén province has a greater number of animals, the number of establishments in Buenos Aires has been increasing in the last few years. The main reasons are the closeness to the commercial and distribution centers, the possibility of place the products in the internal market, the tourist activity of the area, etc. One of the most relevant problems that dairy systems have is to achieve an adequate number of animals for the replacement of females, so the management of the rearing of lambs and kids is critical. In addition, even though milk is the product that gives the greatest economic income to the establishment, its use for feeding the the offspring of small ruminants has a negative impact on the quantity of liters traded. Artificial aging is a common practice implemented in many countries, but in Argentina, it is used only in some establishments. In general, the artificial breeding methodologies implemented are based on recommendations among producers without having a professional base in this regard. For this reason, it is imperative to know if the methodology of artificial breeding considered has an impact on the health and growth of animals, especially when antibiotics are incorporated as a productive tool (either to prevent diseases or as growth promoters). The main objective of this Doctoral Thesis was to evaluate the efficiency of feeding small ruminants under artificial rearing, in relation to their growth and health status, also considering the consequences that different management practices could have on the environment productive. Fil: Galotta, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Unidad Ejecutora de Investigaciones en Producción Animal. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Unidad Ejecutora de Investigaciones en Producción Animal; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Investigación en Biociencias Agricolas y Ambientales. Grupo Vinculado Centro de Estudios Transdisciplinarios del Agua - INBA; Argentina