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Depending on the real parameter λ > 0, we derive existence and non-existence results. The proof of our existence result relies on sharp Calderón–Zygmund type regularity results for the fractional Poisson equation with low integrability data. We also obtain existence results for related problems involving different nonlocal diffusion terms.
There is a long history of exploitation of the South American river turtle Podocnemis expansa. Conservation efforts for this species started in the 1960s but best practices were not established, and population trends and the number of nesting females protected remained unknown. In 2014 we formed a working group to discuss conservation strategies and to compile population data across the species’ range. We analysed the spatial pattern of its abundance in relation to human and natural factors using multiple regression analyses. We found that > 85 conservation programmes are protecting 147,000 nesting females, primarily in Brazil. The top six sites harbour > 100,000 females and should be prioritized for conservation action. Abundance declines with latitude and we found no evidence of human pressure on current turtle abundance patterns. It is presently not possible to estimate the global population trend because the species is not monitored continuously across the Amazon basin. The number of females is increasing at some localities and decreasing at others. However, the current size of the protected population is well below the historical population size estimated from past levels of human consumption, which demonstrates the need for concerted global conservation action. The data and management recommendations compiled here provide the basis for a regional monitoring programme among South American countries.
We prove that if
-triple and not a Cartan factor of rank two, then
satisfies the Mazur–Ulam property, that is, every surjective isometry from the unit sphere of
onto the unit sphere of another real Banach space
extends to a surjective real linear isometry from
Metamaterials offer the possibility to control and manipulate electromagnetic radiation. Spoof surface plasmon metamaterials are the focus of this Element of the Metamaterials Series. The fundamentals of spoof surface plasmons are reviewed, and advances on plasmonic metamaterials based on spoof plasmons are presented. Spoof surface plasmon metamaterials on a wide range of geometries are discussed: from planar platforms to waveguides and localized modes, including cylindrical structures, grooves, wedges, dominos or conformal surface plasmons in ultrathin platforms. The Element closes with a review of recent advances and applications such as Terahertz sensing or integrated devices and circuits.
Heat stress (HS) is among the major limiting factors to growth of broilers. Heat stress also results in changes in the characteristics of the carcass, such as an increase in fat deposition. The molecular mechanisms responsible for fat deposition in broilers as a response to HS remain unknown. The current study aimed to describe the molecular mechanisms associated with the effects of high temperature and feed restriction due to chronic heat exposure at 32 °C, and to describe the resulting changes in the growth performance and carcass characteristics of the broilers at 21 and 42 days of age. In the current study, 441 male Cobb-500® broilers were subjected to three treatments that differed in rearing temperature and feeding regime: chronic HS fed ad libitum (HS/AL), thermoneutral environment fed ad libitum (TN/AL) and TN and pair-feeding on the feed intake (FI) of the heat-exposed group (TN/PF). HS increased fat content in the breast and wings and decreased fat content in the legs, but did not influence abdominal fat. These effects occurred regardless of reducing consumption induced by HS. Furthermore, HS, independently of reduced FI, increased liver sterol-regulatory element-binding protein-1 (SREBP-1) mRNA in both ages and growth hormone receptor (GHR) mRNA at 42days, whereas feed restriction reduced GHR mRNA only at 21days. In conclusion, increased fat content in the breast and wings was accompanied by a higher gene expression of GHR and SREBP-1, suggesting the involvement of both genes in the control of fat deposition in broilers exposed to HS.
In 2007, a partnership was initiated between a small-volume paediatric cardiac surgery unit located in Las Palmas de Gran Canaria, Spain, and a large-volume cardiac surgery unit located in Milan, Italy. The main goal of this partnership was to provide surgical treatment to children with CHD in the Canary Islands.
An operative algorithm for performing surgery in elective, urgent, and emergency cases was adopted by the this joint programme. Demographic and in-hospital variables were collected from the medical records of all the patients who had undergone surgical intervention for CHD from January, 2009 to March, 2013. Data were introduced into the congenital database of the European Congenital Heart Surgeons Association Congenital Database and the database was interrogated.
In total, 65 surgical mission trips were performed during the period of this study. The European Congenital Heart Surgeons Association Congenital Database documented 214 total patients with a mean age at operation of 36.45 months, 316 procedures in total with 198 cardiopulmonary bypass cases, 46 non-cardiopulmonary bypass cases, 26 cardiovascular cases without cardiopulmonary bypass, 22 miscellaneous other types of cases, 16 interventional cardiology cases, six thoracic cases, one non-cardiac, non-thoracic procedure on a cardiac patient with cardiac anaesthesia, and one extracorporeal membrane oxygenation case. The 30-day mortality was 6.07% (13 patients).
A joint programme between a small-volume centre and a large-volume centre may represent a valid and reproducible model for safe paediatric cardiac surgery in the context of a peripheral region.
The possibilities of Ni as contact material in electronic applications has motivated the interest on the intermetallic phases of the Ni-Sb system, in relation to their use in lead free micro-soldering processes. In this work, a detailed theoretical study of the cohesive and thermodynamic properties of the compound Ni3Sb in the (cF16) Fm-3m structure is reported. To this aim, the Full Potential Linearized Augmented Plane Waves method, within the framework of the Density Functional Theory and both Generalized Gradient and Local Density approximations, has been applied. The structural parameters, cohesive and elastic properties of this compound and its constituent elements have been determined. In particular, the equilibrium structural properties are determined through the minimization of the energy, including the full relaxation of the internal degrees of freedom of the cell. It is shown that the calculated properties agree well with the available experimental data. Moreover, various contributions to the electronic density of sates are studied. On this basis, a discussion is presented of the bonding characteristics of this compound, in the framework of the current ideas about cohesion in p-d bonded intermetallics.
Networks of protected areas are one of the main strategies used to address the biodiversity crisis. These should encompass as many species and ecosystems as possible, particularly in territories with high biological diversity, such as the Spanish arid zones. We produce a priority ranking of the arid zones of south-east Spain according to the rarity and richness of their characteristic flora and the level of endangerment. The resulting hierarchy shows that optimal zones for the preservation of the flora are located outside the network of protected areas. In particular, it is important to extend the network and encourage the creation of microreserves in the depression of the River Guadiana Menor (Granada), where there is least protection. This river valley is a particularly important arid site because of its unique flora and fauna, and palaeontological and archaeological findings.
This study's focus is to evaluate a sexual coercion prevention program in adolescents. Using a beforeand- after design with both a treatment group (n = 93) and a control group (n = 76), an intervention of seven sessions was completed. Said sessions included such content as conceptualizing sexual freedom, sexual coercion and voluntary consent, analyzing different sexual coercion tactics and the contexts in which they occur, empathy toward the victim, and developing abilities to avoid risky situations. Other risk factors for coercive behavior and sexual victimization are explored as well, such as alcohol use, sexist attitudes and inadequate communication, among others. The intervention's results include a decrease in stereotypical beliefs about the opposite sex and increased empathy toward victims of sexual coercion. These changes were maintained with the passage of time. Also, in the treatment group, a more acute decline was observed in the proportion of young people engaging in sexually coercive behaviors. This article emphasizes the importance, necessity and efficacy of such interventions, and discusses and analyzes possible improvements to the program for its future implementation.
The aim of this study was to analyze the reliability and validity evidence of scores on the Spanish version of Self-Description Questionnaire II (SDQ-II). The instrument was administered in a sample of 2022 Spanish students (51.1% boys) from grades 7 to 10. Confirmatory factor analysis (CFA) was used to examine validity evidence based on internal structure drawn from the scores on the SDQ-II. CFA replicated the correlated 11 first-order factor structure. Furthermore, hierarchical confirmatory factor analysis (HCFA) was used to examine the hierarchical ordering of self-concept, as measured by scores on the Spanish version of the SDQ-II. Although a series of HCFA models were tested to assess academic and non-academic components organization, support for those hierarchical models was weaker than for the correlated 11 first-order factor structure. Results also indicated that scores on the Spanish version of the SDQ-II had internal consistency and test-retest reliability estimates within an acceptable range.
The tool switching problem (ToSP) is well known in the domain of flexible manufacturing systems. Given a reconfigurable machine, the ToSP amounts to scheduling a collection of jobs on this machine (each of them requiring a different set of tools to be completed), as well as the tools to be loaded/unloaded at each step to process these jobs, such that the total number of tool switches is minimized. Different exact and heuristic methods have been defined to deal with this problem. In this work, we focus on memetic approaches to this problem. To this end, we have considered a number of variants of three different local search techniques (hill climbing, tabu search, and simulated annealing), and embedded them in a permutational evolutionary algorithm. It is shown that the memetic algorithm endowed with steepest ascent hill climbing search yields the best results, performing synergistically better than its stand-alone constituents, and providing better results than the rest of the algorithms (including those returned by an effective ad hoc beam search heuristic defined in the literature for this problem).
An unusual bloom of the cubozoan Carybdea marsupialis occurred at some beaches located near Denia (south-western Mediterranean Sea, south-eastern Spain) during the summer of 2008. The bloom was first detected and recorded by the local Red Cross first aid services. Densities of C. marsupialis in the area were characterized by quantitative sampling. The number of bathers stung totalled 3330 during the three months of summer. Sampling at shallow beaches from 15 September to 21 November 2008 gave insights into cubozoan density in the area, estimated at 265.9 individuals per 100 m2 as the highest value. These densities have never been recorded previously in the Mediterranean where the species was considered to be rare. Mean density along the 17 km of coastline which was sampled reached 5.4 ± 3.8 ind/100 m2. Data on size distribution are also given. This paper analyses the reasons behind these unusually high abundances of C. marsupialis in the north-western Mediterranean Sea and provides guidelines for future studies to elucidate the causes of this bloom.
Capillary liquid flows have shown their ability to generate micro and nano-structures which can be used to synthesize material in the micro or nanometric size range. For instance, electrified capillary liquid jets issued from a Taylor are broadly used to spin micro and nanofibers when the liquid consists of a polymer solution or melt, a process termed electrospinning. In this process, the electrified capillary jet may develop a nonaxisymmetric instability, usually referred to as whipping instability, which very efficiently transforms electric energy into stretching energy, thus leading to the formation of extremely thin polymer fibers. Even though non axysimmetric instabilities of electrified jets were first investigated some decades ago, the existing theoretical models provide a qualitative understanding of the phenomenon but none of them is accurate enough when compared with experimental results. This whipping instability usually manifests itself as fast and violent lateral motion of the charged jet, which makes it difficult its characterization in the laboratory. However, this instability also develops when electrospinning is performed within a liquid bath instead of air. Although it is essentially the same phenomenon, the frequency of the whipping oscillations is much slower in the former case than in the latter, thus allowing detailed experimental characterization of the whipping instability. Furthermore, since the outer fluid is a liquid, its density and viscosity may now be used to influence the dynamics of the electrified capillary jet. In this work we present and rationalize the experimental data collecting the influence of the main parameters on the whipping characteristics of the electrified jet (frequency, amplitude, etc.).
Sow milk protects the piglet against infectious diseases through a variety of mechanisms. In this study, the presence of potentially probiotic lactic acid bacteria in this biological fluid was investigated. Milk samples were obtained from 8 sows and a total of 19 rod-shaped isolates were selected for identification and assessment of their probiotic potential. RAPD profiling revealed the existence of 8 different genetic profiles among them. One representative of each profile was selected for further characterization and they were identified as Lactobacillus reuteri, Lb. salivarius, Lb. plantarum, Lb. paraplantarum, Lb. brevis and Weissella paramesenteroides. Then, their probiotic potential was evaluated through different assays, including survival in conditions simulating those existing in the gastrointestinal tract, production of antimicrobial compounds, adherence to intestinal mucin, production of biogenic amines, degradation of mucin, and pattern of antibiotic sensitivity. Three strains, Lb. reuteri CR20 (a reuterin-producing strain), Lb. salivarius CELA2 (a bacteriocin-producing strain) and Lb. paraplantarum CLB7 displayed the highest probiotic potential.