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Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities.
Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined.
HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior.
Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.
We explore the properties of sound and human sound recognition as a means to enhance and accelerate visual-only data analysis methods. The aim of this work is to enable and improve the analysis of large data sets, data requiring rapid analysis, multi-dimensional data, and signal detection in data with low signal-to-noise ratio. We present a prototype tool, StarSound, to sonify data such as astronomical transient light curves, spectra, and power spectra. Stereophonic sound is used to ‘visualise’ and localise the data under examination, and 3-D sound is discussed in conjunction with virtual reality technology, as a means to enhance analysis efficiency and efficacy, including rapid data assessment and training machine learning software. In addition, we explore the use of higher-order harmonics as a means to examine simultaneously multi-dimensional data sets. Such an approach can allow the data to be interpreted in a holistic manner and facilitates the discovery of previously unseen connections and relationships. Furthermore, we exploit the capability of the human brain for selective or focused hearing that enables the identification of desired signals in noisy data, or amidst similar or more significant signals. Finally, we provide research examples that benefit directly from data sonification. The work presented here aims to help tackle the challenges of the upcoming era of Big Data and help optimise, speed up and expand aspects of data analysis requiring human interaction.
Slaughter is a crucial step in the meat production chain that could induce psychological stress on each animal, resulting in a physiological response that can differ among individuals. The aim of this study was to investigate the relationship between an animal’s emotional state, the subsequent psychological stress at slaughter and the cellular damage as an effect. In all, 36 entire male pigs were reared at an experimental farm and a cognitive bias test was used to classify them into positive bias (PB) or negative bias (NB) groups depending on their decision-making capabilities. Half of the animals, slaughtered in the same batch, were used for a complete study of biomarkers of stress, including brain neurotransmitters and some muscle biomarkers of oxidative stress. After slaughter, specific brain areas were excised and the levels of catecholamines (noradrenaline (NA) and dopamine (DA)) and indoleamines (5-hydroxyindoleacetic acid and serotonin (5HT)) were analyzed. In addition, muscle proteasome activity (20S), antioxidant defence (total antioxidant activity (TAA)), oxidative damage (lipid peroxidation (LPO)) and autophagy biomarkers (Beclin-1, microtubule-associated protein I light chain 3 (LC3-I) and LC3-II) were monitored during early postmortem maturation (0 to 24 h). Compared with PB animals, NB pigs were more susceptible to stress, showing higher 5HT levels (P<0.01) in the hippocampus and lower DA (P<0.001) in the pre-frontal cortex. Furthermore, NB pigs had more intense proteolytic processes and triggered primary muscle cell survival mechanisms immediately after slaughter (0 h postmortem), thus showing higher TAA (P<0.001) and earlier proteasome activity (P<0.001) and autophagy (Beclin-1, P<0.05; LC3-II/LC3-I, P<0.001) than PB pigs, in order to counteract the induced increase in oxidative stress, that was significantly higher in the muscle of NB pigs at 0 h postmortem (LPO, P<0.001). Our study is the first to demonstrate that pig’s cognitive bias influences the animal’s susceptibility to stress and has important effects on the postmortem muscle metabolism, particularly on the cell antioxidant defences and the autophagy onset. These results expand the current knowledge regarding biomarkers of animal welfare and highlight the potential use of biomarkers of the proteasome, the autophagy (Beclin-1, LC3-II/LC3-I ratio) and the muscle antioxidant defence (TAA, LPO) for detection of peri-slaughter stress.
Daytime restricted feeding (2 h of food access from 12.00 to 14.00 hours for 3 weeks) is an experimental protocol that modifies the relationship between metabolic networks and the circadian molecular clock. The precise anatomical locus that controls the biochemical and physiological adaptations to optimise nutrient use is unknown. We explored the changes in liver oxidative lipid handling, such as β-oxidation and its regulation, as well as adaptations in the lipoprotein profile. It was found that daytime restricted feeding promoted an elevation of circulating ketone bodies before mealtime, an altered hepatic daily rhythmicity of 14CO2 production from radioactive palmitic acid, and an up-regulation of the fatty acid oxidation activators, the α-subunit of AMP-activated protein kinase (AMPK), the deacetylase silent mating type information regulation homolog 1, and the transcriptional factor PPARγ-1α coactivator. An increased localisation of phosphorylated α-subunit of AMPK in the periportal hepatocytes was also observed. Liver hepatic lipase C, important for lipoprotein transformation, showed a change of daily phase with a peak at the time of food access. In serum, there was an increase of LDL, which was responsible for a net elevation of circulating cholesterol. We conclude that our results indicate an enhanced fasting response in the liver during daily synchronisation to food access, which involves altered metabolic and cellular control of fatty acid oxidation as well a significant elevation of serum LDL. These adaptations could be part of the metabolic input that underlies the expression of the food-entrained oscillator.
We present a database of 11 interplanetary shocks associated to coronal mass ejections (CMEs) observed by STEREO and Wind missions between 2006 and 2011 that show evidence of Type II radio burst. For all events, we calculated the principal characteristics of the shock driver, the intensity and geometrical configuration of the in-situ shock and checked for the existence of in-situ type II radio burst. We made a comparative analysis of two CME events (on 18 August 2010 and 4 June 2011), which are apparently associated to two or more magnetic structures which interact in space (i.e. CMEs, SIRs, CIRs). These events show varied shock configurations and intensities. We found evidence of in-situ type II radio bursts in one of the events studied, suggesting that the geometry of the shock (quasi-perpendicularity) is also critical for the generation and/or detection of radio emission in-situ.
The alloy composed of zirconium has been used effectively for over 50 years in claddings of nuclear fuel, especially for PWR type reactors. However, to increase fuel enrichment with the aim of rising the burning and maintaining the safety of nuclear plants, is of great relevance the study of new materials that can replace safely and efficiently zircaloy cladding. Among several proposed material, silicon carbide (SiC) has a potential to replace zircaloy as fuel cladding material due to its high-temperature tolerance, chemical stability and a low absorption cross-section for thermal neutrons. In this paper, the goal is to expand the study with silicon carbide cladding, checking its behavior when submitted to an environment with burnable poison variations, the impact on multiplication factor and reactivity coefficients to both claddings: zircaloy and silicon carbide. The neutronic analysis was made using the SCALE 6.0 (Standardized Computer Analysis for Licensing Evaluation) code. This code system is widely accepted and used worldwide for safety analysis, and criticality of nuclear reactors has been utilized to model a typical fuel element of a PWR.
In humans, obesity before and during pregnancy is associated with both fetal macrosomia and growth restriction, and long-term cardiovascular risk in the offspring. We aimed to determine whether overweighted pregnant guinea pig sows results in an increased fetal weight at term and the effects on the vascular reactivity in fetal systemic and umbilical arteries. Pregnant guinea pigs were classified as control (n=4) or high weight (HWS, n=5) according to their pre-mating weight, and their fetuses extracted at 0.9 gestation (~60 days). Segments of fetal femoral and umbilical arteries were mounted in a wire myograph, where the contractile response to KCl (5–125 mM), and the relaxation to nitric oxide synthase-dependent agents (insulin, 10−10–10−7 and acetylcholine, 10−10–10−5) and nitric oxide [sodium nitroprusside (SNP), 10−10–10−5] were determined. Fetuses from HWS (HWSF) were grouped according to their body weight as low (<76 g) or high (>85 g) fetal weight, based on the confidence interval (76.5–84.9 g) of the control group. No HWSF were observed in the normal range. Umbilical arteries from HWSF showed a lower response to KCl and insulin compared with controls, but a comparable response with SNP. Conversely, femoral arteries from HWSF showed an increased response to KCl and acetylcholine, along with a decreased sensitivity to SNP. These data show that overweight sows have altered fetal growth along gestation. Further, large and small fetuses from obese guinea pig sows showed altered vascular reactivity at umbilical and systemic vessels, which potentially associates with long-term cardiovascular risk.
Barb goatgrass is an invasive annual grass from the Mediterranean region that negatively affects both native plant biodiversity and the forage quality of grasslands. Prescribed burning may be the best landscape-level tool available to manage invasive species like barb goatgrass while also enhancing biodiversity, but few studies have quantified the long-term effects of fire on goatgrass and the rest of the plant community. We assessed the effects of fire on an invading front of barb goatgrass on a private ranch in Sacramento County, CA. We established burned and unburned treatment plots within the goatgrass-infested area and used prescribed fire to burn the treatment plots in June 2005. We monitored plant-community composition before burning and for 7 consecutive yr following the burn. Additionally, we tested the viability of goatgrass seeds in both burned and unburned plots. One year after the burn, goatgrass cover in burned plots was 3% compared with 21% in unburned plots. This reduction in goatgrass cover was still strong 2 yr after the burn (burned, 6%; unburned, 27%) and weaker but still statistically significant for 4 of the next 5 yr. The burn also reduced germination of goatgrass seed by 99% as indicated by seed-viability tests conducted in the laboratory. The native plant community responded positively to the burn treatment in the first year following the burn with an increase in native diversity in burned plots vs. unburned plots, but the effect was not detectable in subsequent years. Nonnative annual forb species cover also increased in the first year following the burn. Our study shows that a single springtime burn can result in a short-term boost in native species diversity, reduced seed germination of barb goatgrass to near zero, and reduced cover of barb goatgrass for at least 7 yr after the burn.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
Stegophorus macronectes (Johnston & Mawson, 1942) is a gastrointestinal parasite found in Antarctic seabirds. The original description of the species, which was based only on females, is poor and fragmented with some unclear diagnostic characters. This study provides new morphometric and molecular data on this previously poorly described parasite. Nuclear rDNA sequences (18S, 5.8S, 28S and internal transcribed spacer (ITS) regions) were isolated from S. macronectes specimens collected from the chinstrap penguin Pygoscelis antarctica Forster on Deception Island, Antarctica. Using 18S rDNA sequences, phylogenetic analyses (maximum likelihood, maximum parsimony and Bayesian inference) of the order Spirurida were performed to determine the phylogenetic location of this species. Primer pairs of the ITS regions were designed for genus-level identification of specimens, regardless of their cycle, as an alternative to coprological methods. The utility of this molecular method for identification of morphologically altered specimens is also discussed.
Trajectory patterns of positive, disorganized and negative dimension symptoms during antipsychotic treatment in drug-naive patients with first-episode psychosis have yet to be examined by using naturalistic data.
This pragmatic clinical trial randomized 161 drug-naive patients with a first episode of psychosis to olanzapine, risperidone or haloperidol. Patients were assessed with the Scale for the Assessment of Negative Symptoms (SANS) and Positive Symptoms (SAPS) at baseline and at the end of weeks 1, 2, 3, 4 and 6 of antipsychotic treatment. Censored normal models of response trajectories were developed with three dimensions of the SAPS-SANS scores (positive, disorganized and negative) in order to identify the different response trajectories. Diagnosis, cannabis use, duration of untreated psychosis (DUP), smoking and antipsychotic class were examined as possible predictive variables.
Patients were classified in five groups according to the positive dimension, three groups according to the disorganized dimension and five groups according to the negative dimension. Longer DUPs and cannabis use were associated with higher scores and poorer responses in the positive dimension. Cannabis use was associated with higher scores and poorer responses in the disorganized dimension. Only schizophrenia diagnosis was associated with higher scores and poorer responses in the negative dimension.
Our results illustrate the heterogeneity of short-term response to antipsychotics in patients with a first episode of psychosis and highlight markedly different patterns of response in the positive, disorganized and negative dimensions. DUP, cannabis use and diagnosis appeared to have a prognostic value in predicting treatment response with different implications for each dimension.
Pastes of waste glass (WG) and metakaolin (MK) were prepared by chemical activation with sodium silicate solutions of modulus Ms = 0.5, 0.75, 1 and 1.25 adjusted with sodium hydroxide. An experimental design was carried out using the Taguchi method. The compressive strength (CS) was followed for up to 120 days and then 4 selected formulations of the higher CS were further characterized by X-ray diffraction and scanning electron microscopy. The results showed that the CS depends on the experimental conditions of %WG, %Na2O and Ms and showed a maximum of 70 MPa after 120 days for the paste with 100%WG (%wt.), 8% Na2O and Ms=1.25; while a Portland cement specimen cured at 20°C reached 43MPa. The WG is more reactive than the MK under less alkaline conditions. The features of the microstructures varied notably with the %WG; however all showed relative dense matrices of reaction products, in agreement with the CS attained.
Hybrid nano/micro particles were investigated for their possibility to re-structure within local pH alterations, release certain active substance and further contribute to increased steel corrosion resistance. Two aspects with regard to corrosion control and self-healing in cement-based materials are discussed: the first aspect deals with the electrochemical performance of low carbon steel electrodes (St37) in model alkaline solutions (cement extract) in the presence of 4.9.10-4 g/l hybrid particles i.e. cement extract, containing PDADMAC (poly (diallyl, dimethyl ammonium chloride) / PAA (Poly (acrylic acid)/ PDADMAC over a CaO core. The second aspect refers to the performance of reinforcing steel (FeB500 HKN) in mortar specimens, containing hybrid particles in the mixing water in concentration of 3.6×10-4 wt. % per mortar weight. The main objective was to determine if these hybrids will lead to increased corrosion resistance of the steel surface layers, generally formed in the hereby investigated environmental medium (both liquid i.e. cement extract and solid i.e. mortar). Further, it was expected that when chlorides are involved, as corrosion accelerating factor, the presence of hybrid particles will delay corrosion initiation and will therefore lead to increased corrosion resistance. The results denote for indeed superior corrosion performance of steel in chloride-free and chloride containing medium, when hybrid particles are involved. The responsible mechanisms are related to increased barrier effects of the formed layer and self-repair upon morphological alterations of the hybrid particles, “nucleation sites effects” and/or Ca-core “release” on locally active (anodic) areas on the steel surface.
In this study we analyze the electrical behavior of a junction formed by an ultraheavily Ti implanted Si layer processed by a Pulsed Laser Melting (PLM) and the non implanted Si substrate. This electrical behavior exhibits an electrical decoupling effect in this bilayer that we have associated to an Intermediate Band (IB) formation in the Ti supersaturated Si layer. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements show a Ti depth profile with concentrations well above the theoretical limit required to the IB formation. Sheet resistance and Hall mobility measurements in the van der Pauw configuration of these bilayers exhibit a clear dependence with the different measurement currents introduced (1µA-1mA). We find that the electrical transport properties measured present an electrical decoupling effect in the bilayer as function of the temperature. The dependence of this effect with the injected current could be explained in terms of an additional current flow in the junction from the substrate to the IB layer and in terms of the voltage dependence in the junction with the measurement current.
The Burst Observer and Optical Transient Exploring System (BOOTES), is a global robotic
observatory network, which started in 1998 with Spanish leadership devoted to study
optical emissions from gamma ray bursts (GRBs) that occur in the Universe. We present shot
history and current status of BOOTES network. The Network philosophy, science and some
details of 117 GRBs followed-up are discussed.