Nonlinear Interaction of Transversal Modes in a CO2 Laser

We show the possibility of achieving experimentally a Takens-Bogdanov bifurcation for the nonlinear interaction of two transverse modes ($l = \pm 1$) in a $CO_2$ laser. The system has a basic O(2) symmetry which is perturbed by some symmetry-breaking effects that still preserve the $Z_2$ symmetry. The pattern dynamics near this codimension two bifurcation under such symmetries is described. This dynamics changes drastically when the laser properties are modified.Comment: 16 pages, 0 figure

Development of an RTK GPS plant mapping system for transplanted vegetable crops.

This study investigated the feasibility of using real-time kinematics (RTK) GPS to automatically map the locations of tomato transplants in the field as they are planted using a vegetable crop transplanter retrofitted with an RTK GPS receiver, and an on board real-time controller. Two detection methods were evaluated for sensing plant location during planting. One method used an infrared light beam sensor to detect the stem location of each plant immediately after planting. The second method used an absolute shaft encoder mounted on the planting wheel to sense the location that each plant was placed in the soil. Odometry was used to determine the actual Easting and Northing GPS coordinates of each plant by interpolation from the original RTK GPS data stream. A field test was conducted to compare the accuracy of this transplant map with actual plant location. The average absolute differences between the automatically generated transplant map and the plant location determined by GPS survey was 0.8 to 2.1 cm in the Northing direction and 1.6 to 3.8 cm in the Easting direction, which was also the travel direction. Results suggest the feasibility of creating an accurate plant map using an RTK GPS equipped transplanter

A Transitional Year Level to Higher Education: Challenges, Experiences and Self-regulatory Strategies during the Final Year of the University Preparatory Level

Final Year level of the University Preparatory cycle (FYUP) –in Spanish 2º Bachillerato– is one of the most challenging academic courses. It is extremely demanding academically in itself and by the end of it students must also pass the university entry exam. Yet research has not investigated how students experience this year. We thus explored, using in-depth interviews with 75 students from two public high schools, their attitudes toward this academic year. Our results showed that (a) the participants struggled greatly during FYUP, experiencing high levels of academic stress (that affects their general well-being, mostly because of the high academic demands); (b) students were looking forward to their university experience but were concerned about failing or not finding their place; and (c) they reported a narrow range of learning, motivational, and emotional strategies. This study shows that students face significant learning and academic challenges during FYUP. A clear educational implication is that interventions should be implemented in earlier years to help the students be better prepared

Detection of aluminium hydroxide-induced granulomas in sheep by computed tomography: A feasible approach for small ruminant lentiviruses diagnosis and research

Aluminium (Al) hydroxide use as adjuvant induces local formation of long-lasting subcutaneous granulomas in sheep. Macrophages within these granulomas have been identified as a new small ruminant lentivirus (SRLV) replication site in naturally infected animals. Diagnosis of Al hydroxide-induced granulomas in sheep is mostly based on postmortem observations but little information is available on in vivo detection. Computed tomography (CT) is used for studying these reactions in other animal species. To determine if CT could be a tool for in vivo diagnosis and research of subcutaneous Al hydroxide-induced granulomas in sheep. A retrospective survey on thoracic CT scans was performed on 46 adult sheep. Analysis included absence or presence, number and location of subcutaneous nodules. Thoracic CT scans and pathological studies were prescribed to two further sheep. Single or multiple subcutaneous nodules were detected in 26 (56.52%) sheep. One or two nodules per animal were most often observed (36.95%). Size ranged between 1.5 and 4.5 cm. Pre-contrast two-dimensional (2D) CT images showed focal or multifocal increases in subcutaneous tissue thickness. Post-contrast 2D CT images revealed hypointense areas in the centre. Histopathology indicated the presence of granulomas composed by a large number of activated macrophages, surrounding a central core of necrosis. Large intracytoplasmic Al-positive aggregates were demonstrated by lumogallion staining. CT is a useful tool to detect subcutaneous Al hydroxide-induced granulomas in vivo in sheep. CT provides a diagnostic and research tool that can be very useful in future works in Al hydroxide-induced pathology, SRLV infection, or both. © 2021 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd

Situational analysis of the subjective well-being of university software developers in Puebla

Integral well-being is vital for the optimal functioning of people. The requirements for a software developer in the performance of their professional activity are varied and complex. These requirements range from working in multidisciplinary and multilingual teams, going through the challenge of technological advances of the discipline to commit to quality and innovation. To face these demands, it is essential that the developers have an optimal functioning, where the experience emotional and satisfaction with life play an important role. The objective of this article is to analyze the subjective well-being of university software developers in Puebla. The research is a quantitative cross-correlation study to identify statistically significant relationships between the different welfare variables. The study involved 47 university software developers from the city of Puebla. We use Pearson's multivariate correlation to validate the instruments and find relationships between variables, and Chi-squared statistics to calculate the dependency between them. The results reveal that the university software developers experience with higher incidence and intensity, the positive affections over the negatives. The affective balance (Net Affect), calculated as the difference of the weighted averages by duration between positive affective states and negative, was positive (mean = 1.31). "Concentrated" is the positive affective state with the highest incidence and with the highest reported intensity. "Tired" is the most experienced negative affect and highest in intensity. Developers spend 40% of their time experiencing negative affective states (U-index) and are moderately satisfied with their lives in general

Supramolecular coordination chemistry of aromatic polyoxalamide ligands: A metallosupramolecular approach toward functional magnetic materials

The impressive potential of the metallosupramolecular approach in designing new functional magnetic materials constitutes a great scientific challenge for the chemical research community that requires an interdisciplinary collaboration. New fundamental concepts and future applications in nanoscience and nanotechnology will emerge from the study of magnetism as a supramolecular function in metallosupramolecular chemistry. Our recent work on the rich supramolecular coordination chemistry of a novel family of aromatic polyoxalamide (APOXA) ligands with first-row transition metal ions has allowed us to move one step further in the rational design of metallosupramolecular assemblies of increasing structural and magnetic complexity. Thus, we have taken advantage of the new developments of metallosupramolecular chemistry and, in particular, the molecular-programmed self-assembly methods that exploit the coordination preferences of paramagnetic metal ions and suitable designed polytopic ligands. The resulting self-assembled di- and trinuclear metallacyclic complexes with APOXA ligands, either metallacyclophanes or metallacryptands, are indeed ideal model systems for the study of the electron exchange mechanism between paramagnetic metal centers through extended π-conjugated aromatic bridges. So, the influence of different factors such as the topology and conformation of the bridging ligand or the electronic configuration and magnetic anisotropy of the metal ion have been investigated in a systematic way. These oligonuclear metallacyclic complexes can be important in the development of a new class of molecular magnetic devices, such as molecular magnetic wires (MMWs) and switches (MMSs), which are major goals in the field of molecular electronics and spintronics. On the other hand, because of their metal binding capacity through the outer carbonyl-oxygen atoms of the oxamato groups, they can further be used as ligands, referred to as metal–organic ligands (MOLs), toward either coordinatively unsaturated metal complexes or fully solvated metal ions. This well-known “complex-as-ligand” approach affords a wide variety of high-nuclearity metal–organic clusters (MOCs) and high-dimensionality metal–organic polymers (MOPs). The judicious choice of the oligonuclear MOL, ranging from mono- to di- and trinuclear species, has allowed us to control the overall structure and magnetic properties of the final oxamato-bridged multidimensional (nD, n = 0–3) MOCs and MOPs. The intercrossing between short- (nanoscopic) and long-range (macroscopic) magnetic behavior has been investigated in this unique family of oxamato-bridged metallosupramolecular magnetic materials expanding the examples of low-dimensional, single-molecule (SMMs) and single-chain (SCMs) magnets and high-dimensional, open-framework magnets (OFMs), which are brand-new targets in the field of molecular magnetism and materials science

Determinación de los perfiles sensoriales característicos de la aceituna Aloreña

Aloreña olives are unique to and typical of the Guadalhorce region (Málaga, Spain). They possess some specific characteristics which make them an excellent product that is differentiated from the other olive varieties. The sensory profile technique was used to study the sensory attributes which best characterize the three processing styles of Aloreña table-olives. The characteristic descriptors are identified according to the round-table method and multivariate analysis. Sensory profile data obtained were analyzed using a mix of Nested Design ANOVA and Factorial ANOVA and by a canonical analysis. The effect of the factor processing style was significant only for three descriptors: fruit odor, bitter taste and firmness (p < 0.05) whereas the effect of the samples nested in each processing style was significant for all the attributes (p < 0.001). Duncan’s post hoc test and the canonical analysis showed that all samples were different within each processing style.La aceituna Aloreña es una variedad de aceituna de mesa autóctona de la comarca del Valle del Guadalhorce (Málaga, España) que posee unas características propias que la distingue del resto de variedades, siendo las propiedades sensoriales las que mejor la diferencian. Para estudiar los atributos sensoriales que mejor definen a los tres tipos de elaboración de la aceituna Aloreña (verdes frescas, tradicionales y curadas) se utiliza la técnica del perfil sensorial. La selección de atributos sensoriales se realiza mediante discusión grupal en mesa redonda y utilizando análisis multivariante. Los datos obtenidos de los perfiles sensoriales se analizan utilizando un modelo mixto de análisis de la varianza (anidado x factorial) y un análisis canónico. Los resultados del análisis de varianza indican que las principales diferencias entre estilos de elaboración se deben a los atributos frutado, sabor amargo y firmeza (p < 0.05) y que las diferencias entre muestras, dentro de cada estilo de elaboración, se deben a todos los atributos estudiados (p < 0.001). El test de medias de Duncan y el análisis canónico muestran que todas las muestras son diferentes dentro de cada estilo de elaboración

Influencia de las características del suelo en el acogollado de lechugas (Lactuca sativa var. capitata L-4)

La lechuga se cultiva extensivamente en el área Mediterránea, y es la provincia de Murcia la que tiene una producciónmas elevada, siendo la variedad más exportada la Iceberg, que es la estudiada en este trabajo (Lactuca sativavar. capitata L-4).Al ser el acogollado una de las características agronómicas mas interesantes para esta hortaliza, en este trabajoestudiamos las características del suelo en el fenómeno del acogollado.De acuerdo con las condiciones de cultivo en la zona de Pozoestrecho (Murcia), se toman muestras de (Torriorthenttípico) y de material vegetal; concluyendo que el contenido en arcilla del suelo más favorable para el acogollado dela variedad estudiada está comprendido entre el 25-55%, que corresponde a texturas francas, arcillo-arenosas yarcillo-limosas.Se ha observado que al aumentar la salinidad el acogollado es menor y que los cultivos que se realizan entre Octubrey Mayo necesitan un aporte suplementario de agua

The shape of oxygen abundance profiles explored with MUSE: evidence for widespread deviations from single gradients

We characterised the oxygen abundance radial distribution of a sample of 102 spiral galaxies observed with VLT/MUSE using the O3N2 calibrator. The high spatial resolution of the data allowed us to detect 14345 H ii regions with the same image quality as with photometric data, avoiding any dilution effect. We developed a new methodology to automatically fit the abundance radial profiles, finding that 55 galaxies of the sample exhibit a single negative gradient. The remaining 47 galaxies also display, as well as this negative trend, either an inner drop in the abundances (21), an outer flattening (10), or both (16), which suggests that these features are a common property of disc galaxies. The presence and depth of the inner drop depends on the stellar mass of the galaxies with the most massive systems presenting the deepest abundance drops, while there is no such dependence in the case of the outer flattening. We find that the inner drop appears always around 0.5 r, while the position of the outer flattening varies over a wide range of galactocentric distances. Regarding the main negative gradient, we find a characteristic slope in the sample of α =-0.10 ± 0.03 dex /r. This slope is independent of the presence of bars and the density of the environment. However, when inner drops or outer flattenings are detected, slightly steeper gradients are observed. This suggests that radial motions might play an important role in shaping the abundance profiles. We define a new normalisation scale (>the abundance scale length>, r) for the radial profiles based on the characteristic abundance gradient, with which all the galaxies show a similar position for the inner drop (~0.5 r) and the outer flattening (~1.5 r). Finally, we find no significant dependence of the dispersion around the negative gradient with any property of the galaxies, with values compatible with the uncertainties associated with the derivation of the abundances.© ESO, 2018.This study is based on observations made with ESO Telescopes at the Paranal Observatory (programmes 60.A-9329(A), 095.D-0172(A), 95.D-0091(A), 95.D-0091(B), 096.D-0263(A), 96.D-0296(A), 97.D-0408(A) and 98.D-0115(A)) and has also made use of the services of the ESO Science Archive Facility (programmes 60.A-9319(A), 60.A-9100(B), 60.A-9329(A), 60.A-9339(A), 60.A-9301(A), 196.B-0578(A) and 094.B-0733(B)). We would like to thank the anonymous referee for comments which helped to improve the content of the paper. We acknowledge financial support from the Spanish Ministerio de Economia y Competitividad (MINECO) via grants AYA2012-31935, and from the >Junta de Andalucia> local government through the FQM-108 project. We also acknowledge support to the ConaCyt funding programme 180125 and DGAPA IA100815. L.G. is supported in part by the US National Science Foundation under Grant AST-1311862. T.K. acknowledges support through the Sofja Kovalevskaja Award to P. Schady from the Alexander von Humboldt Foundation of Germany. We acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr).This research also makes use of python (http://www.python.org),of Matplotlib (Hunter 2007), a suite of open-source python modules that provides a framework for creating scientific plots, and Astropy, a community-developed core Python package for Astronomy (Astropy Collaboration et al. 2013).Peer reviewe