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Important Bird and Biodiversity Areas (IBAs) are sites identified as being globally important for the conservation of bird populations on the basis of an internationally agreed set of criteria. We present the first review of the development and spread of the IBA concept since it was launched by BirdLife International (then ICBP) in 1979 and examine some of the characteristics of the resulting inventory. Over 13,000 global and regional IBAs have so far been identified and documented in terrestrial, freshwater and marine ecosystems in almost all of the world’s countries and territories, making this the largest global network of sites of significance for biodiversity. IBAs have been identified using standardised, data-driven criteria that have been developed and applied at global and regional levels. These criteria capture multiple dimensions of a site’s significance for avian biodiversity and relate to populations of globally threatened species (68.6% of the 10,746 IBAs that meet global criteria), restricted-range species (25.4%), biome-restricted species (27.5%) and congregatory species (50.3%); many global IBAs (52.7%) trigger two or more of these criteria. IBAs range in size from < 1 km2 to over 300,000 km2 and have an approximately log-normal size distribution (median = 125.0 km2, mean = 1,202.6 km2). They cover approximately 6.7% of the terrestrial, 1.6% of the marine and 3.1% of the total surface area of the Earth. The launch in 2016 of the KBA Global Standard, which aims to identify, document and conserve sites that contribute to the global persistence of wider biodiversity, and whose criteria for site identification build on those developed for IBAs, is a logical evolution of the IBA concept. The role of IBAs in conservation planning, policy and practice is reviewed elsewhere. Future technical priorities for the IBA initiative include completion of the global inventory, particularly in the marine environment, keeping the dataset up to date, and improving the systematic monitoring of these sites.
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.
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.
A protective coating was built and assessed in order to reduce the degradation of metallic substrates caused by corrosion damage. Hence, a set of coatings with different configurations, in terms of layer arrangement, was produced by flame-spraying of composite powder (AISI 316L stainless steel coated with an α-alumina layer) onto an AISI 1018 steel substrate. In order to ensure a homogeneous dispersion of phases, a correlation was established between the operating parameters of thermal spraying (roughness and surface temperature of substrate, spraying distance, passing speed) and the splat formation. Then, corrosion damage caused in the coated samples by exposure to a salt spray was monitored through weight measurements and observations with optical and scanning electron microscopy. The results show that corrosion still remains in all cases; however, it proceeds at lower rates for coatings made with composite particles plus an α-alumina layer. The weight loss due to corrosion damage was reduced in approximately 94% as compared with the substrate without protection. Coating adhesion was also improved by an increased substrate roughness, with no need for an intermediate layer.
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.
In the developing of scaffolds for cell culture, a large number of architectures with different combinations of properties should be tested to determine the best. This can be costly in time, money and materials. In this paper we have proposed an optimization model that aims to maximize the growth of osteoblasts on polymeric scaffolds by regulating their properties and architecture. Based on the optimization model it was implemented a genetic algorithm to calculate the architecture and properties of the scaffolds. The fiber diameter, pore diameter, porosity, Young's modulus and contact angle of the scaffolds were calculated through four electrospinning parameters: voltage (kV), concentration (% w/v), flow rate (ml/h) and distance (cm). A fitness value was assigned to each scaffold and the highest one was chosen as the best condition for osteoblast growth. The preliminary results obtained by the Genetic Algorithm were consistent with the tendencies reported experimentally in other studies. Also, the methodology established here can be easily adapted to different types of polymers and cells. Finally, the optimization model can be applied not only by means of heuristic method, like a Genetic Algorithm, but also by exact methods.
The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and HARPSpol. Our preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these objects. We discuss in this contribution some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects.
The purpose of this paper was to prepare purified Na- bentonite with improved properties for use in the pharmaceutical industry. Calcium bentonite from the Shagia region of Karak district, Pakistan, was activated with various proportions of sodium carbonate (2, 3, 5 and 8 wt.%) and purified by sedimentation to remove impurities, especially quartz. X-ray diffraction (XRD), and swelling volume confirmed the conversion of raw bentonite to sodium bentonite by using 5% Na2CO3. The sodium bentonite (K5) obtained by activation met the chemical and microbiological requirements set by the pharmacopeias regarding the toxic trace elemental content (Pb and As), absence of E. coli, total aerobic microbial contents and physicochemical properties such as swelling volume, pH and sedimentation volume. Therefore K5 bentonite could be designated as potentially suitable for pharmaceutical applications. The CEC, surface area, porosity, pH, gel formation and swelling volume indicated that K5 bentonite could be used in the formulation of oral suspension and in topical application.
The aim of the study was the construction of risk maps for exposure to Phlebotomus sergenti, the main vector of Leishmania tropica, with a view to identifying hot spots for the potential establishment of this parasite in the southwest of Europe. Data were collected on the presence/absence of this vector and the ecological and climatic characteristics of 662 sampling sites located in the southeast, centre and northeast of the Iberian Peninsula (south-western Europe). The environmental factors associated with the distribution of P. sergenti were determined. The best predictors for the presence of this dipteran were ‘altitude’, ‘land use’, ‘land surface temperature’, ‘aspect’, ‘adjacent land cover’, ‘absence of vegetation in wall’ and the ‘absence of PVC pipes in the drainage holes of retaining walls’. Risk maps for exposure to the vector were drawn up based on these variables. The validation of the predictive risk model confirmed its usefulness in the detection of areas with a high risk of P. sergenti being present. These locations represent potential hot spots for an autochthonous focus of L. tropica becoming established. The risk maps produced for P. sergenti presence revealed several areas in the centre and south of the Iberian Peninsula to be the most prone to this process, which would make it possible for the disease to enter south-western Europe.
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.
ZnO is a promising material for use in solar cell applications which require antireflective coatings and transparent conducting materials in front contacts. Its resistivity can be reduced by appropriate doping with different group III elements, which act as donors, without sacrificing optical transmission. Besides, it constitutes a non-toxic and cheap alternative to ITO (In2O3:SnO2), which is nowadays commonly used as transparent conducting oxide (TCO) in optoelectronic devices. Al(III) is one of the cheapest elements on nature, and has been therefore one of the first candidates to be used as a dopant. However recent studies demonstrate that for similar amounts of dopant the use of Ga largely improves both the optical and electrical properties of the films. The interface between Si (used as substrate) and the corresponding TCO is a critical part of Si-based solar cells, since the conversion efficiency may be profoundly altered by the presence of recombination centers formed at the interface. In this work we present a comparison of Si/ZnO, Si/ZnO:Ga and Si/ZnO:Al interfaces (with [dopant]/[Zn] = 2%) by using HRTEM and associated spectroscopies. Resistivity values of the films are: ρ(ZnO) = 4.4 × 10-2 Ω × cm; ρ(Ga:ZnO) = 6.3 × 10-4 Ω × cm; ρ(Al:ZnO) = 2.9 × 10-3 Ω × cm. and the films optical transmitance is larger than 80% along the visible spectrum.
The present study investigated the association between cardiorespiratory fitness (CRF) and dietary intake in European adolescents. The study comprised 1492 adolescents (770 females) from eight European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. CRF was assessed by the 20 m shuttle run test. Adolescents were grouped into low and high CRF levels according to the FITNESSGRAM Standards. Dietary intake was self-registered by the adolescents using a computer-based tool for 24 h dietary recalls (HELENA-Dietary Assessment Tool) on two non-consecutive days. Weight and height were measured, and BMI was calculated. Higher CRF was associated with higher total energy intake in boys (P = 0·003). No association was found between CRF and macronutrient intake (as percentage of energy), yet some positive associations were found with daily intake of bread/cereals in boys and dairy products in both boys and girls (all P < 0·003), regardless of centre, age and BMI. CRF was inversely related to sweetened beverage consumption in girls. These findings were overall consistent when CRF was analysed according to the FITNESSGRAM categories (high/low CRF). A high CRF was not related to compliance with dietary recommendations, except for sweetened beverages in girls (P = 0·002). In conclusion, a high CRF is associated with a higher intake of dairy products and bread/cereals, and a lower consumption of sweetened beverages, regardless of centre, age and BMI. The present findings contribute to the understanding of the relationships between dietary factors and physiological health indicators such as CRF.
A well characterized C60 supersonic seeded beam has been used to synthesize SiC films on Si (111) 7×7. The control of beam parameters such as energy and flux distributions is shown to be important to improve quality of films in terms of morphology, defect density and structure. We demonstrate that a kinetic energy of a few eV of the C60 precursor is enough to induce carbidization at moderate substrate temperature. Kinetic energy activated SiC formation at 750°C is achieved with a strong reduction of the dimensions and density of defects. The films show a reduced roughness of about 2.5 nm (root mean square).
Recent research using molecular dynamics to simulate radiation damage due to displacement cascades in metals is reviewed. It includes results dealing with the effect on defect formation of primary knock-on atom energy and irradiation temperature. Clear dependencies and trends have emerged in these areas. In terms of the development of models to describe the evolution of radiation damage microstructure, the important parameters are not only the total number of Frenkel defects but also the distribution of their population in clusters and the form and mobility of these clusters. Results on these aspects are reviewed and it is shown that computer simulation is providing detailed information that paves the way for successful development of models of the evolution of damage beyond the stage of the cascade process.
Organic chromophores have been exploited for a wide range of discrete optical and electronic functions as well as a growing number of combined opto-electronic functions. We are pursuing development of organic and polymer materials for a range of applications that require properties including liquid crystallinity, second order optical nonlinearity, photorefractivity and, more recently, special nonlinear optical behavior involving molecular chirality.