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Pure monoclinic P21/c VO2 thermochromic ceramics are fabricated based on an accessible and simple method using thermal decomposition synthesis in an organic medium. Well-developed submicron crystals with different morphologies are obtained when calcination temperature is varied from 500 to 700 °C. XRD shows that calcination temperature is necessary to form the monoclinic thermochromic phase and to attain high crystallinity. A pure monoclinic VO2 phase is obtained with our methodology and contrasting with other methods in which mixed vanadium oxide phases appear. Thermodiffraction analysis reveals the structural reversibility of the monoclinic-rutile-monoclinic structure during the phase transition. Additionally, DSC analysis shows the hysteretic thermochromic transition between 60 and 70 °C. Measurements of the optical properties through diffuse reflectance in the visible, and near-infrared ranges and performed as a function of the temperature, exhibit a metal–insulator phase transition in agreement with DSC analysis and thermodiffraction. Our results show that thermal decomposition can be a successful methodology for synthesizing monoclinic VO2 with high quality, purity, and reproducibility. [ABSTRACT FROM AUTHOR]

C dating of human remains from the necropolis overlaying the forum of the Roman city of Pollentia (Mallorca, Balearic Islands, Western Mediterranean) has helped to solve the problem of the chronology of these burials. Traditionally, this necropolis was thought to date from the fourth century AD. Recent archaeological data suggested a later chronology with graves that follow funerary practices considered of the Late Antique Christian communities on the island. The results of the radiocarbon dating provide an unexpected dating from the tenth to the twelfth centuries, well into the Islamic period (AD 902/903-1229). The results are of extreme importance as they offer, for the first time, an absolute chronology for this necropolis. Furthermore, they may provide archaeological evidence of the existence of non-Muslim communities into the Muslim period on the island. This absolute chronology and its implications are a major breakthrough for the history of Pollentia, Mallorca and the Balearics. [ABSTRACT FROM AUTHOR]

Gilles de la Tourette syndrome (GTS) is characterized by motor and vocal tics and often associated with obsessive-compulsive disorder (OCD). Responses to intermittent/continuous theta-burst stimulation (iTBS/cTBS), which probe long-term potentiation (LTP)-/depression (LTD)-like plasticity in the primary motor cortex (M1), are reduced in GTS. ITBS-/cTBS-induced M1 plasticity can be affected by brain-derived neurotrophic factor (BDNF) polymorphism. We investigated whether the BDNF polymorphism influences iTBS-/cTBS-induced LTP-/LTD-like M1 plasticity in 50 GTS patients and in 50 age- and sex-matched healthy subjects. In GTS patients, motor and psychiatric (OCD) symptom severity was rated using the Yale Global Tic Severity Scale (YGTSS) and the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). We compared M1 iTBS-/cTBS-induced plasticity in healthy subjects and in patients with GTS. We also compared responses to TBS according to BDNF polymorphism (Val/Val vs Met carriers) in patients and controls. Fourteen healthy subjects and 13 GTS patients were Met carriers. When considering the whole group of controls, as expected, iTBS increased whereas cTBS decreased MEPs. Differently, iTBS/cTBS failed to induce LTP-/LTD-like plasticity in patients with GTS. When comparing responses to TBS according to BDNF polymorphism, in healthy subjects, Met carriers showed reduced MEP changes compared with Val/Val individuals. Conversely, in patients with GTS, responses to iTBS/cTBS were comparable in Val/Val individuals and Met carriers. YGTSS and Y-BOCS scores were comparable in Met carriers and in Val/Val subjects. We conclude that iTBS and cTBS failed to induce LTP-/LTD-like plasticity in patients with GTS, and this was not affected by BDNF genotype. [ABSTRACT FROM AUTHOR]

This paper reports on the influence of dithionite (SO ) as a reducing agent in the Au-SO complex and the main kinetic parameters involved during the precipitation reaction. Results show that it is possible to achieve recoveries of 99% Au in the system Au-SO -SO -O in a time of 60 min at room temperature. The precipitation reaction is characterized by an induction period, followed by a period of gradual precipitation in which the maximum recovery of Au occurs until a stabilization period is reached. The apparent reaction order of [SO ] was n = 0.45, [SO ] was n = −0.8, with respect to [OH] was n≈0 (between 10and 10 M) and with respect to [Au] was n = 0.81. The apparent activation energy was Ea = 32.6 kj mol. This indicates that under these conditions the precipitation of Au in the system Au-SO -SO -O is carried out by a mixed control, although the value obtained tends to be more of a chemical control, this being independent from hydrodynamic variables of the system. [ABSTRACT FROM AUTHOR]

Epoxy resin was mixed with phenolic resins in different percentages by weight. Composite 40/60 means the proportion by weight of epoxy resin is 40%. It was found that only composites 50/50 and 40/60 could be cured in ambient conditions. Dynamic mechanical analysis showed that only these two composites form interpenetrating polymer network. The addition of linseed oil to the two resins results also in the formation of interpenetrating network irrespective of proportion by weight of the resins; the mechanical properties will only be better when the percentage by weight of epoxy resin is higher; the aim of reducing cost and at the same time maintaining the mechanical properties cannot be fully achieved because epoxy resin is much more expensive than its counterpart. [ABSTRACT FROM AUTHOR]

The Cardona Diapir in NE Spain, with a salt outcrop about 0.9 km2 in area, has a well-developed endokarstic system that used to discharge into the Cardener River. Underground mining for potassium salt carried out from 1930 to 1990 caused significant changes in the topography and hydrology of the diapir. The accumulation of two halite slag heaps, totalling around 10 million tons, locally dammed the surface drainage, creating closed depressions and preferential zones of water recharge. The waters that infiltrated in one of these depressions, largely derived from uncontrolled sewage disposal, led to the generation of a 335-m-long human-induced cave excavated in one of the slag heaps. Moreover, the inflow of freshwater from the surrounding sandstone aquifer, caused by the excavation of a ventilation gallery, resulted in the generation of a 280-m-long cave. In March 1998, the interception of a phreatic conduit by a halite mine gallery 50 m deep caused dramatic changes in the hydrology and geomorphology of the diapir, including: (a) a sudden decline in the piezometric level of the karstic aquifer; (b) the inflow of freshwater and debris from the Cardener River into the endokarstic system and the mine galleries. A tunnel had to be constructed to divert the river flow from the salt outcrop; (c) massive dissolution of salt, creating new cavities and enlarging the pre-existing ones, including both mine galleries or cave passages. The 4,300-m-long Salt Meanders Cave was largely generated by the inrush of water from the Cardener River into the mine galleries; and (d) the generation of a large number of sinkholes in the vicinity of the Cardener River. An inventory of 178 sinkholes has allowed us to estimate minimum probability values of 4.7 and 8 sinkholes/km2·year for time intervals previous and subsequent to the 1998 mine flood event, respectively. [ABSTRACT FROM AUTHOR]

In Spain, evaporite outcrops cover approximately 7% of the total area of the country. Most of the evaporitic formations are made up of Ca-sulfates (gypsum/anhydrite) or Ca-sulfates and halite. Certain Paleogene marine evaporites also contain K-Mg-chlorides, and some Tertiary continental formations bear substantial amounts of Na-sulfates in the subsurface (glauberite and thenardite). Mesozoic evaporitic formations commonly wedge out towards the ground surface, passing into condensed sequences and dissolution-collapse breccias. Some of these highly porous breccias constitute major regional aquifers. In several areas, interstratal karstification of the evaporites has given rise to gravitational deformations such as basin structures, monoclines, and collapse structures covering several square kilometers that record a cumulative subsidence in excess of 200 m (Teruel and Calatayud Grabens). A widespread consequence of evaporite dissolution processes in Spain is the hydrochemical degradation of surface waters. Some of the largest and most outstanding lake systems, from an environmental perspective, occur in karstic depressions developed in evaporitic formations (Fuente de Piedra, Gallocanta, Bujaraloz, and Bañolas lakes). Sinkhole activity is a major geohazard in several evaporite karst areas. The sinkhole risk has a particularly high impact in sectors where Tertiary evaporites are overlain by Quaternary alluvial aquifers (Calatayud, Zaragoza, and Madrid areas). Some of the detrimental effects of subsidence include severe damage to historical monuments (Calatayud), the demolition of a whole village (Puilatos), or the derailment of a freight train (Zaragoza area). The deepest gypsum caves are found in Triassic diapiric structures (El Sumidor Cave, 210 m deep), and the longest ones are developed in horizontally lying Neogene sequences (Sorbas caves, and Estremera maze cave). The Cardona diapir hosts salt caves up to 4,300 m long whose genesis is related to flooding of mine galleries caused by the interception of a phreatic conduit. The main anthropogenic impacts on the endokarstic systems are related to the disposal of wastewaters and the destruction of caves by quarrying. The fluvial valleys that cross Tertiary evaporitic outcrops commonly show peculiar geological characteristics related to dissolution-induced synsedimentary subsidence phenomena: (1) Thickened alluvium filling dissolution basins up to several tens of kilometers long and more than 100 m deep. The largest thickenings are found in areas where the bedrock contains halite and glauberite. (2) Superimposed alluvial units locally bounded by angular unconformities. (3) Abundant deformational structures and paleosinkholes related to the rockhead and/or interstratal karstification of the substratum. These fluvial valleys typically are flanked by a prominent gypsum escarpment. Rock-falls favored by the dissolutional enlargement of joints derived from these scarps are the type of mass movement which has caused the highest number of casualties in Spain. [ABSTRACT FROM AUTHOR]

Objective: Few epidemiological studies have examined the relationship of dietary fatty acids, especially MUFA, with the interrelation between insulin secretion and insulin resistance. We assessed the relation of dietary fatty acids with insulin secretion in a free-living population. Design and setting: This cross-sectional, population-based study was undertaken in Pizarra, a small town in Spain. Subjects and methods: Anthropometrical data were collected for 1226 persons selected randomly from the municipal census, 538 of whom (randomly chosen) were given a prospective, quantitative, 7-day nutritional questionnaire. The fatty acid composition of the serum phospholipids was used as a biological marker of the type of fat consumed. Beta-cell function (βCFI) and insulin-resistance index (IRI) were estimated by the Homeostasis Model Assessment. Results: To determine which factors influence the variability of the βCFI, we analyzed the variance of the βCFI according to sex, the presence of carbohydrate metabolism disorders and the different components of the diet, adjusting the models for age, body mass index (BMI) and IRI. The dietary MUFA and polyunsaturated fatty acids (PUFA) contributed to the variability of the βCFI, whereas only the proportion of serum phospholipid MUFA, but neither the saturated fatty acids nor the PUFA accounted for part of the variability of the βCFI in a multiple regression analysis. Conclusion: The results of this population-based study corroborate the results of other clinical and experimental studies suggesting a favorable relationship of MUFA with β-cell insulin secretion. Sponsorship: Fondo de Investigación Sanitaria, Junta de Andalucía and the Asociación Maimónides. [ABSTRACT FROM AUTHOR]

Decreased sensing of the innate immune system may lead to chronic activation of the inflammatory cascade. We hypothesised that mannan-binding lectin (MBL) deficiency may confer risk of obesity and insulin resistance. We performed a cross-sectional study of MBL protein concentration ( n=434) and MBL2 gene mutations (exon 1) ( n=759) in association with obesity, markers of inflammation and insulin action (euglycaemic clamp, n=113), and a longitudinal study of MBL protein before and after weight loss in obese patients ( n=10). We also studied the effects of MBL in vitro in muscle cells and circulating MBL-A (mouse equivalent of human MBL) in a mouse model. Among 434 consecutive non-diabetic men, the age-adjusted serum MBL concentration was lower in obese subjects than in lean subjects (median: 959 μg/ml [interquartile range: 116.8–2,044 μg/ml] vs 1,365 [467–2,513] μg/ml; p=0.01) and was accompanied by increased serum inflammatory markers. Insulin action correlated significantly with serum MBL ( r=0.49, p<0.0001). Serum MBL concentration increased by a median of 110.2% after weight loss. The change in serum concentration of MBL was positively associated with the increase in insulin sensitivity ( r=0.713, p=0.021). At least one MBL2 gene mutation was present in 48.2% of obese vs 39.3% of non-obese subjects ( p=0.037). The plasma concentration of MBL-A was lower in insulin-resistant obese ob/ ob mice, as was the glucose/insulin ratio. Incubation of rat soleus muscle with human MBL markedly increased fatty acid oxidation. These findings suggest that MBL, previously thought only to be involved in inflammation and immune system function, affects metabolic pathways. [ABSTRACT FROM AUTHOR]

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The clinical diagnosis of ataxia-telangiectasia (AT) is difficult before the age of 4 years. We report clinical and cytogenetic data on three early-onset, early-diagnosed AT patients at the age of 12, 18 and 22 months, respectively. Postural instability of the trunk, characterized by motor impersistence, was the earliest neurological sign detected as early as 1 year of life. Dystonic movements and postures of arms and trunk and a subtle disorder of eye movement (blinking before gaze changing, increased latency and dysmetry of saccades) were observed during the 2nd year of life. All patients exhibited an unusual temper tantrum. We also observed an increased bleomycin-induced chromosomal instability in patient's cells in the early stages of the disease before all the clinical hallmarks were apparent. Our data suggest that detection of clinical indications, leading to early laboratory confirmation of AT, can reduce the age at diagnosis. [ABSTRACT FROM AUTHOR]