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Introduction: One of the consequences of the increase in the number of social network users has been the inappropriate use of social networks by some of these users. Hate speeches are frequently identified on social media, and these promote certain homophobic and transphobic attitudes, causing psychological consequences on users belonging to minority gender groups. With this work, it is intended to know the current state of the problem raised, to facilitate the activity of new researchers in an emerging field. Methodology: Bibliographic analysis of 203 papers from the Scopus databases for the period between 1997 and 2022 using the VOSViewer software. The search for publications was carried out in February 2023. Results: There is a positive trend in the number of relevant publications since 2017, mainly in 2021 and 2022. The research on homophobia and transphobia on social media in USA is prominent, with a high number of published articles, productive organizations, and influential authors. Twitter is shown to be the social network most widely used to spread homotransphobic hate speech. Environments conducive to the development of homotransphobic attitudes are identified as collective sports, mainly football and its supporters, as well as peer groups. Conclusions: It is a growing problem that requires intervention at the societal level, requiring the development of legislation that moves away from heteronormativity, the development of mechanisms for automatic detection of homotransphobic discourse on social networks, and a multidisciplinary analysis and approach to control the problem as well as provide adequate social support to affected groups. [ABSTRACT FROM AUTHOR]

Tourism is one of the fastest-growing economic sectors. This has piqued increasing interest in the evaluation of the performance of the sector. This paper joins this line of research by providing a potential framework for measuring efficiency in the context of a country such as Spain, where sun-and-sand tourism, usually associated with mass tourism, predominates. Tourist areas located on the coast provide the units of reference. Data Envelopment Analysis (DEA) is applied to determine the efficiency score and a Tobit-type model is employed to analyse the factors that determine efficiency. The results show that the impact of mass tourism on labour efficiency is geographically unequal, with the most efficient of the tourist areas located on the peninsular archipelagos. The analysis of the contribution of each input to the efficiency score reveals the pre-eminent role of tourism infrastructure as a lure for sun-and-sand tourism. [ABSTRACT FROM AUTHOR]

Purpose: Chondrosarcoma and osteosarcoma are the most frequently occurring bone cancers. Although surgery and chemotherapy are currently clinically applied, improved treatment options are urgently needed. Melatonin is known to inhibit cell proliferation in both tumor types. Although the underlying mechanisms are not clear yet, calcium homeostasis has been reported to be a key factor in cancer biology. Here, we set out to investigate whether regulation of calcium by this indolamine may be involved in its antitumor effect. Methods: Cell viability was measured using a MTT assay and flow cytometry was used to measure levels of cytosolic calcium, intracellular oxidants, mitochondrial membrane potential and cell cycle progression. Mitochondrial calcium was analyzed by fluorimetry. Cell migration was determined using a scratch wound-healing assay. Western blot analysis was used to assess the expression of proteins related to cell cycle progression, epithelial to mesenchymal transition (EMT), Ac-CoA synthesis and intracellular signaling pathways. Results: We found that melatonin decreases cytosolic and mitochondrial Ca2+ levels, intracellular oxidant levels, mitochondrial function and the expression of the E1 subunit of the pyruvate dehydrogenase complex. These changes were found to be accompanied by decreases in cell proliferation, cell migration and EMT marker expression. The addition of CaCl2 prevented the changes mentioned above, while co-treatment with the calcium chelator BAPTA enhanced the effects. Conclusions: Our data indicate that regulation of calcium homeostasis is a key factor in the inhibition of cell proliferation and migration by melatonin. This effect should be taken into consideration in combined therapies with traditional or new antitumor compounds, since it may circumvent therapy resistance. [ABSTRACT FROM AUTHOR]

Aims: An unresolved question in plant ecology is whether diversity of the aboveground and belowground compartments of a plant community is similar at different neighbourhood scales. We investigated how the similarity between both compartments varies with the aboveground sampling grain and if significant discrepancies exist between aboveground and belowground plant diversity at the maximum similarity scale. Methods: We fully mapped the aboveground perennial plant community of a 64 m2 plot in a Mediterranean shrubland and analysed this compartment by assessing diversity in 5 to 50 cm radii circles centred in soil cores. We sampled 2.5 cm radius root cores at two different depths and identified plant species by using DNA metabarcoding to characterise the belowground compartment. We quantified differences in species richness, composition and species' spatial distribution above- and belowground. Results: The differences between aboveground and belowground communities were affected by the size of the aboveground sampling grain and were minimised when considering a circle of 20 cm radius in the aboveground. We found a significant dissimilarity in richness and composition between the two compartments, with larger differences when considering the deeper soil layer only. Conclusions: Our results showed that the spatial grain selected to sample a plant community aboveground and belowground is critical to characterise them in a comparable manner. Although their composition is related, species distribution patterns strongly differ, suggesting the simultaneous action of different assembly mechanisms. Our results call for caution when studying community assembly considering only the standing vegetation, since total plant diversity can be underappreciated. [ABSTRACT FROM AUTHOR]

Population persistence is strongly determined by climatic variability. Changes in the patterns of climatic events linked to global warming may alter population dynamics, but their effects may be strongly modulated by biotic interactions. Plant populations interact with each other in such a way that responses to climate of a single population may impact the dynamics of the whole community. In this study, we assess how climate variability affects persistence and coexistence of two dominant plant species in a semiarid shrub community on gypsum soils. We use 9 years of demographic data to parameterize demographic models and to simulate population dynamics under different climatic and ecological scenarios. We observe that populations of both coexisting species may respond to common climatic fluctuations both similarly and in idiosyncratic ways, depending on the yearly combination of climatic factors. Biotic interactions (both within and among species) modulate some of their vital rates, but their effects on population dynamics highly depend on climatic fluctuations. Our results indicate that increased levels of climatic variability may alter interspecific relationships. These alterations might potentially affect species coexistence, disrupting competitive hierarchies and ultimately leading to abrupt changes in community composition. [ABSTRACT FROM AUTHOR]

Effective doping of semiconductor oxide nanostructures is needed to control n-type conductivity; however, out-diffusion of impurities in high quality crystals is still a bottleneck in nanotechnology. Here, germanium-doped gallium oxide (β-Ga2O3) nanowires have been grown by a thermal evaporation method. Two temperatures, close to Ge melting point, were chosen for the dynamic annealing of metallic gallium and germanium powders. At 840 °C, Ga2O3 nanowires and nanobelts grow along the b or c direction, leaving gallium germanate particles at the tip in both cases. Wider structures were produced at 940 °C, decorated with a Ge nanocrystal at the end. Transmission electron microscopy has been used to establish the vapor–liquid–solid-like growth process for the formation of these structures. The influence of Ge incorporation in the nanostructures has been assessed by cathodoluminescence and micro-Raman spectroscopy. The presence of Ge in β-Ga2O3 nanostructures is essential for electronic and optoelectronic applications since Ge is potentially the most effective n-type dopant for β-Ga2O3. [ABSTRACT FROM AUTHOR]

Low levels of phosphate in blood secondary to a lack of phosphorous reabsorption in the renal tubule cause hypophosphataemic rickets. To increase blood calcium levels, bone calcium is released into the bloodstream by increasing the activity of osteoclasts in the bones. These alterations in bone metabolism lead to delayed growth and small height, diffuse bone pain, bone fragility with microfractures, and frequent fractures and bone deformities. Although management of some of these conditions is mainly conservative, in cases of bone deformities or severe osteomalacia surgery should be considered: from minimally invasive surgical techniques of guided growth in patients with less deformity and open physeal cartilage to correction osteotomies in three-dimensional deformities. This article briefly reviews the indications for surgery procedures to be performed in these patients, highlighting when to use aggressive and non-aggressive approaches. [ABSTRACT FROM AUTHOR]