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First-degree relatives of patients with psychotic disorder have higher levels of polygenic risk (PRS) for schizophrenia and higher levels of intermediate phenotypes.
We conducted, using two different samples for discovery (n = 336 controls and 649 siblings of patients with psychotic disorder) and replication (n = 1208 controls and 1106 siblings), an analysis of association between PRS on the one hand and psychopathological and cognitive intermediate phenotypes of schizophrenia on the other in a sample at average genetic risk (healthy controls) and a sample at higher than average risk (healthy siblings of patients). Two subthreshold psychosis phenotypes, as well as a standardised measure of cognitive ability, based on a short version of the WAIS-III short form, were used. In addition, a measure of jumping to conclusion bias (replication sample only) was tested for association with PRS.
In both discovery and replication sample, evidence for an association between PRS and subthreshold psychosis phenotypes was observed in the relatives of patients, whereas in the controls no association was observed. Jumping to conclusion bias was similarly only associated with PRS in the sibling group. Cognitive ability was weakly negatively and non-significantly associated with PRS in both the sibling and the control group.
The degree of endophenotypic expression of schizophrenia polygenic risk depends on having a sibling with psychotic disorder, suggestive of underlying gene–environment interaction. Cognitive biases may better index genetic risk of disorder than traditional measures of neurocognition, which instead may reflect the population distribution of cognitive ability impacting the prognosis of psychotic disorder.
Isotopic composition of leaf carbon (δ13C) and nitrogen (δ15N) is determined by biotic and abiotic factors. In order to determine the influence of leaf habit and site on leaf δ13C and δ15N in the understorey of two Atlantic forests in Brazil that differ in annual precipitation (1200 and 1900 mm), we measured these isotopes in the shaded understorey of 38 tropical tree species (20 in the 1200-mm site and 18 in the 1900-mm site). Mean site values for δ15N were significantly lower at the 1200-mm site (−1.4‰) compared with the 1900-mm site (+3.0‰), and δ13C was significantly greater in the 1200-mm site (−30.4‰) than in the 1900-mm site (−31.6‰). Leaf C concentration was greater and leaf N concentration was lower at 1200-mm than at 1900-mm. Leaf δ15N was negatively correlated with δ13C across the two sites. Leaf δ13C and δ15N of evergreen and deciduous species were not significantly different within a site. No significant phylogenetic signal for any traits among the study species was found. Overall, site differences were the main factor distinguishing traits among species, suggesting strong functional convergence to local climate and soils within each site for individuals in the shaded understorey.
The total solar eclipse of July 11, 1991 was observed from “La Matanza”, Baja California Sur, México, only 5 km south of the center line of totality, with several small instruments intended to obtain images of the corona during totality, and using a range of exposure times which allowed us to detect both the inner and outer corona. Relations between large and fine scale structures of the corona, the photospheric and chromospheric activity, and the presence of coronal holes are presented.
In Spain, the use of annual cover crops is a crop management practice for irrigated vineyards that allows controlling vineyard vigor and yield, which also leads to improve the crop quality. Recently, Cynodon dactylon (bermudagrass) has been reported to infest those cover crops and colonize the grapevine rows, resulting in significant yield and economic losses due to the competition for water and nutrients. From timely unmanned aerial vehicle (UAV) imagery, the objective of this research was to map C. dactylon patches in order to provide an optimized site-specific weed management. A quadrocopter UAV equipped with a point-and-shoot camera was used to collect a set of aerial red-green-blue (RGB) images over a commercial vineyard plot, coinciding with the dormant period of C. dactylon (February 2016). Object-based image analysis (OBIA) techniques were used to develop an innovative algorithm for early discrimination and mapping of C. dactylon, which had the ability to solve the limitation of spectral similarity of this weed with cover crops or bare soil. As a general result, the classified maps of the studied vineyard showed four main classes, i.e. vine, cover crop, C. dactylon and bare soil, with 85% overall accuracy. These weed maps allow developing new strategies for site-specific control of C. dactylon populations in the context of precision viticulture.
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.
There are many advantages to studying variable stars in open clusters; the parameters that determine the evolution of the stars, such as chemical composition and age, can be considered to be the same for all the stars in the cluster. These data, along with the mass, effective temperature and superficial gravity, allow us to better determine the physics which explain the pulsation mechanisms. In the present paper the variable stars h501 and h906 in α Per and w2 and w20 in NGC 2264 are studied. In particular, the reasons why δ Scuti stars coexist with early type stars in NGC 2264 is examined.
Use of cooled and frozen semen is becoming increasingly prevalent in the equine industry. However, these procedures cause harmful effects in the sperm cell resulting in reduced cell lifespan and fertility rates. Apoptosis and necrosis-related events are increased during semen cryopreservation. However, a third type of cell death, named autophagy, has not been studied during equine semen storage. Light chain (LC)3 protein is a key component of the autophagy pathway. Under autophagy activation, LC3-I is lipidated and converted to LC3-II. The ratio of LC3-II/LC3-I is widely used as a marker of autophagy activation. The main objective of this study was to investigate whether LC3 is processed during cooling, freezing and the stressful conditions associated with these technologies. A secondary objective was to determine if LC3 processing can be modulated and if that may improve the quality of cryopreserved semen. LC3 processing was studied by Western blot with a specific antibody that recognized both LC3-I and LC3-II. Viability was assessed by flow cytometry. Modulation of LC3-I to LC3-II was studied with known autophagy activators (STF-62247 and rapamycin) or inhibitors (chloroquine and 3-MA) used in somatic cells. The results showed that conversion of LC3-I to LC3-II increased significantly during cooling at 4°C, freezing/thawing and each of the stressful conditions tested (UV radiation, oxidative stress, osmotic stress and changes in temperature). STF-62247 and rapamycin increased the LC3-II/LC3-I ratio and decreased the viability of equine sperm, whereas chloroquine and 3-MA inhibited LC3 processing and maintained the percentage of viable cells after 2 h of incubation at 37°C. Finally, refrigeration at 4°C for 96 h and freezing at −196°C in the presence of chloroquine and 3-MA resulted in higher percentages of viable cells. In conclusion, results showed that an ‘autophagy-like’ mechanism may be involved in the regulation of sperm viability during equine semen cryopreservation. Modulation of autophagy during these reproductive technologies may result in an improvement of semen quality and therefore in higher fertility rates.
The aim of this study was to determine the seroprevalence of Toxoplasma gondii infection in free-range chickens from Uberlândia, Minas Gerais state, Brazil, and characterize the genotypic and phenotypic features of two isolates of this parasite, considering the importance of these hosts in the epidemiology of toxoplasmosis. Serum samples from 108 free-range chickens were obtained from ten different districts, and submitted to the modified agglutination test (MAT) for the presence of anti-T. gondii antibodies, and brain and heart tissue samples from infected chickens were processed for mouse bioassay. An overall seroprevalence of 71·3% was found and antibody titres ranged from 16 to 4096. After confirmation of seropositivity by mouse bioassay, the determination of the T. gondii genotypes of two isolates was performed by PCR–RFLP, using primers for the following markers: SAG1, SAG2, SAG3, BTUB, GRA6, c22–8, c29–2, L358, PK1, new SAG2, Apico and CS3. These T. gondii isolates, designated TgChBrUD1and TgChBrUD2, were obtained from heart samples of free-range chickens. The TgChBrUD1 isolate belonged to ToxoDB PCR–RFLP genotype 11 and the TgChBrUD2 isolate belonged to ToxoDB PCR–RFLP genotype 6. Both isolates demonstrated high virulence in a rodent model, with the TgChBrUD1 isolate able to induce brain cysts, in accord with its pattern of multiplication rates in human fibroblast culture. Taken together, these results reveal high prevalence of T. gondii infection in free-range chickens throughout Uberlândia, indicating an important degree of oocyst environmental contamination and the existence of considerable risk for T. gondii transmission to humans by consumption of free-range chicken as a food source.
The objective of this study was to estimate the relationship between serum vitamin D (VitD) status and tuberculosis (TB) infection conversion (TBIC), measured by the tuberculin skin test (TST) and an interferon-gamma release assay, the QuantiFERON-TB Gold In-Tube (QFT-GIT) test, in the contacts of pulmonary TB patients in Castellon (Spain) in a prospective cohort study from 2010 to 2012. Initially, the participants were negative to latent TB infection after a screening that included TST and QFT-GIT tests, and other examinations. A baseline determination of 25-hydroxyvitamin D [25(OH)D] was obtained by chemiluminescence immunoassay. After 8–10 weeks, participants were screened for a second time to determine TB infection conversion (TBIC). Poisson regression models were used in the statistical analysis. Of the 247 participants in the cohort, 198 (80·2%) were screened twice and 18 (9·1%) were TBIC cases. The means of VitD concentration in the TBIC cases and the non-cases were 20·7±11·9 and 27·2±11·4 ng/ml (P = 0·028), respectively. Adjusted for high exposure and TB sputum acid-fast bacilli (AFB)-positive index case, higher serum VitD concentration was associated with low incidence of TBIC (Ptrend = 0·005), and an increase of 1 ng/ml VitD concentration decreased the incidence of TBIC by 6% (relative risk 0·94, 95% confidence interval 0·90–0·99, P = 0·015). The results suggest that sufficient VitD level could be a protective factor of TBIC.
In recent years, an extensive collection of Toxoplasma gondii samples have been typed using a set of 10 PCR-RFLP genetic markers. Here we summarize the data reported until the end of 2012. A total of 1457 samples were typed into 189 genotypes. Overall, only a few genotypes dominate in the northern hemisphere, which is in stark contrast to the southern hemisphere where hundreds of genotypes coexist with none being notably dominant. PCR-RFLP genotype #1 (Type II clonal), #2 (Type III), #3 (Type II variant) and #10 (Type I) are identified globally. Genotypes #2 and #3 dominate in Africa, genotypes #9 (Chinese 1) and #10 are prevalent in Asia, genotypes #1, #2 and #3 are prevalent in Europe, genotypes #1, #2, #3, #4 and #5 dominate in North America (#4 and #5 are collectively known as Type 12). In Central and South America, there is no clear dominance of any genotype even though a few have relatively higher frequencies. Statistical analysis indicates significant differences among populations in Africa, Asia, Europe, North America, and Central and South America, with only Europe and North America exhibiting similar diversity. Collectively, the results revealed distinct population structures and geographical patterns of diversity in T. gondii.
The Vista Variables in the Vía Láctea (VVV) ESO Public Survey is an ongoing time-series, near-infrared (IR) survey of the Galactic bulge and an adjacent portion of the inner disk, covering 562 square degrees of the sky, using ESO's VISTA telescope. The survey has provided superb multi-color photometry in 5 broadband filters (Z, Y, J, H, and Ks), leading to the best map of the inner Milky Way ever obtained, particularly in the near-IR. The main part of the survey, which is focused on the variability in the Ks-band, is currently underway, with bulge fields observed between 34 and 73 times, and disk fields between 34 and 36 times. When the survey is complete, bulge (disk) fields will have been observed up to a total of 100 (60) times, providing unprecedented depth and time coverage in the near-IR. Here we provide a first overview of stellar variability in the VVV data.
Here we present the installation and successful commissioning of an L'-band Annular Groove Phase Mask (AGPM) coronagraph on VLT/NACO. The AGPM is a vector vortex coronagraph made from diamond subwavelength gratings tuned to the L' band. The vector vortex coronagraph enables high contrast imaging at very small inner working angle (here 0″.09, the diffraction limit of the VLT at L'), potentially being the key to a new parameter space. During technical and science verification runs, we discovered a late-type companion at two beamwidths from an F0V star (Mawet et al. 2013), and imaged the inner regions of β Pictoris down to the previously unexplored projected radius of 1.75 AU. The circumstellar disk was also resolved from ≃ 1″ to 5″ (see J. Milli et al., these proceedings). These results showcase the potential of the NACO L-band AGPM over a wide range of spatial scales.
The protection of sunflower meal (SFM) proteins by treatments with solutions of malic acid (1 M) or orthophosphoric acid (0.67 M) and heat was studied in a 3 × 3 Latin-square design using three diets and three rumen and duodenum cannulated wethers. Acid solutions were applied to SFM at a rate of 400 ml/kg under continuous mixing. Subsequently, treated meals were dried in an oven at 150°C for 6 h. Diets (ingested at 75 g/kg BW0.75) were isoproteic and included 40% Italian ryegrass hay and 60% concentrate. The ratio of untreated to treated SFM in the concentrate was 100 : 0 in the control diet and around 40 : 60 in diets including acid-treated meals. The use of acid-treated meals did not alter either ruminal fermentation or composition of rumen contents and led to moderate reductions of the rumen outflow rates of untreated SFM particles, whereas it did not affect their comminution and mixing rate. In situ effective estimates of by-pass (BP) and its intestinal effective digestibility (IED) of dry matter (DM), CP and amino acids (AAs) were obtained considering both rates and correcting the particle microbial contamination in the rumen using 15N infusion techniques. Estimates of BP and IED decreased applying microbial correction, but these variations were low in agreement with the small contamination level. Protective treatments increased on average the BP of DM (48.5%) and CP (267%), mainly decreasing both the soluble fraction and the degradation rate but also increasing the undegradable fraction, which was higher using orthophosphoric acid. Protective treatments increased the IED of DM (108%) and CP, but this increase was lower using orthophosphoric acid (11.8%) than malic acid (20.7%). Concentrations of AA were similar among all meals, except for a reduction in lysine concentrations using malic acid (16.3%) or orthophosphoric acid (20.5%). Protective treatments also increased on average the BP of all AA, as well as the IED of most of them. Evidence of higher increases for those AA showing a high resistance to degradation in the untreated meal were also observed. The total supply of metabolisable AA was increased by 3.87 times for sulphur-containing AA, whereas that of lysine was increased by 2.5 times, mainly because of lysine losses with heat treatments. These treatments and especially that with malic acid would be useful to increase the protein value of these meals but their combined use with lysine-rich protein concentrates would improve the metabolisable protein profile.
New data and a review of historiographic information from Neolithic sites of the Malaga and Algarve coasts (southern Iberian Peninsula) and from the Maghreb (North Africa) reveal the existence of a Neolithic settlement at least from 7.5 cal ka BP. The agricultural and pastoralist food producing economy of that population rapidly replaced the coastal economies of the Mesolithic populations. The timing of this population and economic turnover coincided with major changes in the continental and marine ecosystems, including upwelling intensity, sea-level changes and increased aridity in the Sahara and along the Iberian coast. These changes likely impacted the subsistence strategies of the Mesolithic populations along the Iberian seascapes and resulted in abandonments manifested as sedimentary hiatuses in some areas during the Mesolithic–Neolithic transition. The rapid expansion and area of dispersal of the early Neolithic traits suggest the use of marine technology. Different evidences for a Maghrebian origin for the first colonists have been summarized. The recognition of an early North-African Neolithic influence in Southern Iberia and the Maghreb is vital for understanding the appearance and development of the Neolithic in Western Europe. Our review suggests links between climate change, resource allocation, and population turnover.
We report large magnetoresistance (in excess of 1000%) in ferromagnet / superconductor / ferromagnet structures made of La0.7Ca0.3MnO3 and YBa2Cu3O7 in the current in plane (CIP) geometry. This magnetoresistance has many of the ingredients of the giant magnetoresistance of metallic superlattices: it is independent on the angle between current and magnetic field, depends on the relative orientation of the magnetization in the ferromagnetic layers, and takes very large values. The origin is enhanced scattering at the F/S interface in the anti parallel configuration of the magnetizations. Furthermore, we examine the dependence of the magnetoresistance effect on the thickness of the superconducting layer, and show that the magnetoresistance dies out for thickness in excess of 30 nm, setting a length scale for the diffusion of spin polarized quasiparticles.
In this work we show that the addition of a small amount of CF4 to a regular CH4 -H2 gas mixture allows diamond growth at lower temperatures with reasonable growth rates. We used a hot filament assisted reactor and observed diamond growth with a substrate temperature as low as 390 ଌ. We present a comparative study for the growth dependence on substrate temperature with and without CF4 addition in the gas mixture. The growth rate is measured by post growth weighting with a micro balance. Raman spectroscopy, SEM and AFM images show the good quality of the films grown at low temperatures when CF4 is added to the feeding gas.
The research about the structural stability of bone, as a composite material, compromises a complete understanding of the interaction between the mineral and organic phases. The thermal stability of human bone and type I collagen extracted from human bone by different methods was studied in order to understand the interactions between the mineral and organic phases when is affected by a degradation/combustion process. The experimental techniques employed were calorimetry and infrared spectroscopy (FTIR) techniques. The extracted type I collagens result to have a bigger thermal stability with a Tmax at 500 and 530 Celsius degrees compared with the collagen present in bone with Tmax at 350 Celsius degrees. The enthalpy value for the complete degradation/combustion process were similar for all the samples, being 8.4 +- 0.11 kJ/g for recent bones diminishing with the antiquity, while for extracted collagens were 8.9 +- 0.07 and 7.9 +-1.01 kJ/g. These findings demonstrate that the stability loss of type I collagen is due to its interactions with the mineral phase, namely carbonate hydroxyapatite. This cause a change in the molecular properties of the collagen during mineralization, specifically in its cross-links and other chemical interactions, which have a global effect over the fibers elasticity, but gaining tensile strength in bone as a whole tissue. We are applying this characterization to analyze the diagenetic process of bones with archaeological interest in order to identify how the environmental factors affect the molecular structure of type I collagen. In bone samples that proceed from an specific region with the same environmental conditions, the enthalpy value per unit mass was found to diminish exponentially with respect to the bone antiquity.
The identification of early changes in the sperm plasmalemma is currently a factor in the improvement of freezing protocols. We analysed the presence of active caspases in freeze–thawed (FT) dog spermatozoa, and evaluated straws from eight dogs using flow cytometry and fluorescence microscopy with fluorescein isothyocyanate–Val–Ala–Asp–fluoromethylketone (FITC–VAD–fmk) combined with ethidum homodimers. Apoptotic-like changes were evaluated using the YO–PRO-1/ethidium homodimer combination, and changes in mitochondrial membrane potential were monitored with JC-1. Sperm motility post-thaw was evaluated using a CASA system. FITC–VAD–fmk stained sperm cells in situ and the subcellular labelling pattern was consistent with known localization of caspases. On average, a high proportion of FT canine sperm showed caspase activity, ranging from 30.2 to 70.7% of the live sperm compared with 7.3 to 24.0% in dead spermatozoa. This observed differentiation between caspase activity in dead and live spermatozoa may be a simple method to disclose subtle differences in sperm quality, since this staining allowed us to find statistically significant differences among dogs. Notably, the sperm sample with overall better results in all sperm parameters studied after thawing had a lower percentage of active caspases in both dead and live spermatozoa.
The 70 kDa heat-shock protein (Hsp70) sequences are considered one of the most conserved proteins in all domains of life from Archaea to eukaryotes. Hammondia heydorni, H. hammondi, Toxoplasma gondii, Neospora hughesi and N. caninum (Hammondia-like organisms) are closely related tissue cyst-forming coccidians that belong to the subfamily Toxoplasmatinae. The phylogenetic reconstruction using cytoplasmic Hsp70 coding genes of Hammondia-like organisms revealed the genetic sequences of T. gondii, Neospora spp. and H. heydorni to possess similar levels of evolutionary distance. In addition, at least 2 distinct genetic groups could be recognized among the H. heydorni isolates. Such results are in agreement with those obtained with internal transcribed spacer-1 rDNA (ITS-1) sequences. In order to compare the nucleotide diversity among different taxonomic levels within Apicomplexa, Hsp70 coding sequences of the following apicomplexan organisms were included in this study: Cryptosporidium, Theileria, Babesia, Plasmodium and Cyclospora. Such analysis revealed the Hammondia-like organism to be the lowest divergent group when compared to other groups within the phylum Apicomplexa. In conclusion, the Hsp70 coding sequences proved to be a valuable genetic marker for phylogenetic reconstruction and may constitute a good candidate to be used with other genes for species phylogeny within this group of organisms.