Consequences of spontaneous reconnection at a two-dimensional non-force-free current layer

Magnetic neutral points, where the magnitude of the magnetic field vanishes locally, are potential locations for energy conversion in the solar corona. The fact that the magnetic field is identically zero at these points suggests that for the study of current sheet formation and of any subsequent resistive dissipation phase, a finite beta plasma should be considered, rather than neglecting the plasma pressure as has often been the case in the past. The rapid dissipation of a finite current layer in non-force-free equilibrium is investigated numerically, after the sudden onset of an anomalous resistivity. The aim of this study is to determine how the energy is redistributed during the initial diffusion phase, and what is the nature of the outward transmission of information and energy. The resistivity rapidly diffuses the current at the null point. The presence of a plasma pressure allows the vast majority of the free energy to be transferred into internal energy. Most of the converted energy is used in direct heating of the surrounding plasma, and only about 3% is converted into kinetic energy, causing a perturbation in the magnetic field and the plasma which propagates away from the null at the local fast magnetoacoustic speed. The propagating pulses show a complex structure due to the highly non-uniform initial state. It is shown that this perturbation carries no net current as it propagates away from the null. The fact that, under the assumptions taken in this paper, most of the magnetic energy released in the reconnection converts internal energy of the plasma, may be highly important for the chromospheric and coronal heating problem

Social media as a means to access millennial wine consumers

Purpose The purpose of this research is to gain insights of the use of social media (SM) in the wine industry. From the theoretical viewpoint to analyze wineries’ social media segmentation, targeting and positioning (STP) to help the wine industry to improve the effectiveness of SM communication. Design/methodology/approach An observational study of Spanish wineries’ SM presence and traffic was carried out during a three-month period in 2013 and repeated in 2016. During this period a questionnaire was distributed to 196 wineries. Logistic regression was used to model the dichotomous outcome variable of whether a winery “does” or “does not” utilise SM. Additionally, leader wineries were interviewed in April/May 2016 about SM segmentation, targeting and positioning (STP). Findings The results show that most wineries are starting in SM without a well-defined strategy. The presence of a webpage is significantly related to the use of SM. SM wineries do not segment and can take advantage of digital targeting strategies. Practical implications Segmentation and targeting SM can improve the effectiveness of the winery SM activities as well as the winery competitiveness in the wine industry. Originality/value This research is a first step in understanding the value of segmentation SM to reach millennial consumers and the importance of targeting to improve the effectiveness of winery on S

The onset of Impulsive Bursty reconnection at a two-dimensional current layer

The sudden reconnection of a non-force free 2D current layer, embedded in a low-beta plasma, triggered by the onset of an anomalous resistivity, is studied in detail. The resulting behaviour consists of two main phases. Firstly, a transient reconnection phase, in which the current in the layer is rapidly dispersed and some flux is reconnected. This dispersal of current launches a family of small amplitude magnetic and plasma perturbations, which propagate away from the null at the local fast and slow magnetosonic speeds. The vast majority of the magnetic energy released in this phase goes into internal energy of the plasma, and only a tiny amount is converted into kinetic energy. In the wake of the outwards propagating pulses, an imbalance of Lorentz and pressure forces creates a stagnation flow which drives a regime of impulsive bursty reconnection, in which fast reconnection is turned on and off in a turbulent manner as the current density exceeds and falls below a critical value. During this phase, the null current density is continuously built up above a certain critical level, then dissipated very rapidly, and built up again, in a stochastic manner. Interestingly, the magnetic energy converted during this quasi-steady phase is greater than that converted during the initial transient reconnection phase. Again essentially all the energy converted during this phase goes directly to internal energy. These results are of potential importance for solar flares and coronal heating, and set a conceptually important reference for future 3D studies

Oral lichenoid lesions related to contact with dental materials : a literature review

Oral lichenoid lesions related to contact are defined as oral-cavity eruptions with an identifiable etiology, and are clinically and histologically similar to oral lichen planus. Within this group are found oral lichenoid lesions related to contact with dental materials (OLLC), the most common being those related to silver amalgam. Currently, it remains difficult to diagnose these lesions due to the clinical and histopathological similarity with oral lichen planus and other oral mucosa lesions of lichenoid characteristics. In the present paper, we carry out an updated review of the tests for, and the different characteristics of OLLC, which may aid the diagnosis. For this review, we made searches in the Pubmed® and Cochrane® databases. Among the literature we found several published papers, from which we have used review papers, case papers, cohort studies, case and control studies, and a meta-analysis study. After carrying out this review, we can conclude that the diagnosis of these lesions is still difficult and controversial. However, there are different aspects in the clinical presentation, pathological study and results obtained when replacing suspect materials, which, when taken together, may be useful when establishing the final diagnosis of OLLC

Composición, propiedades, estabilidad y comportamiento térmico del aceite de semilla de tamarindo (Tamarindus indica)

The composition, thermal stability and phase behavior of tamarind (Tamarindus indica) seed oil were analyzed to contribute to the exploration of their potential uses. The oil was extracted from the kernel of the tamarind seed with hexane, and its main physical, chemical and thermal properties were analyzed by infrared spectrometry, gas chromatography-mass spectrometry, DSC, and TGA. The results showed that the tamarind seed had a 3.76 ± 0.20% oil with a saponification index of 174.80 ± 9.87 mg KOH/g and the major fatty acids were lignoceric (20.15%), oleic (18.99%) and palmitic (11.99%). Stearic, behenic, linoleic, arachidic, and other fatty acids were also present. TGA and DSC showed that in an inert atmosphere, the triacylglycerols of tamarind seed oil (TSO) are decomposed in a single stage that starts at 224.1 °C and in an air atmosphere in three stages, initiating its decomposition at 218 °C. The TSO showed crystallization and fusion curves with a single maximum peak with Tonset and Toffset of 20.16 and ?38.8 °C and ?22.2 and 28.6 °C, respectively. The solid fat profile of the oil showed a semi-solid and liquid consistency in the ambient temperature range. The composition, thermal and phase behavior showed that TSO is potentially useful for alimentary, pharmacological, and cosmetological purposes.La composición, estabilidad y comportamiento térmico del aceite de semilla de tamarindo (Tamarindus indica) fueron analizadas con el fin de contribuir al conocimiento de sus potenciales usos. El aceite fue extraído del núcleo de la semilla con hexano y analizado mediante sus principales propiedades físicas, químicas y térmicas mediante espectrometría infrarroja, cromatografía de gases, espectroscopia de masas, calorimetría (DSC) y termogravimetría (TGA). Los resultados mostraron que las semillas del tamarindo tuvieron un contenido de aceite de 3,76 ± 0,20%, con un índice de saponificación de 174,80 ± 9,87mg KOH/g y ácidos grasos mayoritarios: Lignocérico (20,15%), oleico (18,99%), palmítico (11,99%) y en cantidades menores los ácidos esteárico, behénico, linoleico y araquídico, entre otros. El análisis mediante TGA y DSC mostró que la temperatura inicial de descomposición del aceite fue de 224,1 °C en una sola etapa en atmósfera inerte y en atmósfera de aire fue a 218 °C en tres etapas. El aceite mostró curvas de cristalización y fusión con un solo máximo, iniciándose y finalizando estos cambios de fase a 20,16 y -38,8 °C, and -22,2 y 28,6 °C, respectivamente. Estas propiedades mostraron que el aceite de la semilla de tamarindo tiene potenciales aplicaciones en alimentos y productos farmacológicos y cosméticos

ALBAYZIN 2018 spoken term detection evaluation: a multi-domain international evaluation in Spanish

[Abstract] Search on speech (SoS) is a challenging area due to the huge amount of information stored in audio and video repositories. Spoken term detection (STD) is an SoS-related task aiming to retrieve data from a speech repository given a textual representation of a search term (which can include one or more words). This paper presents a multi-domain internationally open evaluation for STD in Spanish. The evaluation has been designed carefully so that several analyses of the main results can be carried out. The evaluation task aims at retrieving the speech files that contain the terms, providing their start and end times, and a score that reflects the confidence given to the detection. Three different Spanish speech databases that encompass different domains have been employed in the evaluation: the MAVIR database, which comprises a set of talks from workshops; the RTVE database, which includes broadcast news programs; and the COREMAH database, which contains 2-people spontaneous speech conversations about different topics. We present the evaluation itself, the three databases, the evaluation metric, the systems submitted to the evaluation, the results, and detailed post-evaluation analyses based on some term properties (within-vocabulary/out-of-vocabulary terms, single-word/multi-word terms, and native/foreign terms). Fusion results of the primary systems submitted to the evaluation are also presented. Three different research groups took part in the evaluation, and 11 different systems were submitted. The obtained results suggest that the STD task is still in progress and performance is highly sensitive to changes in the data domain.Ministerio de Economía y Competitividad; TIN2015-64282-R,Ministerio de Economía y Competitividad; RTI2018-093336-B-C22Ministerio de Economía y Competitividad; TEC2015-65345-PXunta de Galicia; ED431B 2016/035Xunta de Galicia; GPC ED431B 2019/003Xunta de Galicia; GRC 2014/024Xunta de Galicia; ED431G/01Xunta de Galicia; ED431G/04Agrupación estratéxica consolidada; GIU16/68Ministerio de Economía y Competitividad; TEC2015-68172-C2-1-

Short-term variability in the activity and composition of the diazotroph community in a coastal upwelling system

Today we know that diazotrophs are common and active in nitrogen (N) replete regions, however the factors controlling their distribution remain elusive. Previous studies in upwelling regions revealed that the composition of diazotrophs responded to changes in hydrodynamic forcing over seasonal scales. Here we used high-frequency observations collected during a 3-week cruise in the upwelling region off NW Iberia to describe changes in the activity and composition of diazotrophs over shorter temporal scales. The cruise started after a strong upwelling event followed by a few days of relaxation-downwelling, and soon after another upwelling pulse. Higher N2 fixation rates (2.2 ± 0.7 µmol m-3 d-1) were measured during relaxation-downwelling, when surface nitrate concentration was low. During the fertilization associated with the upwelling, N2 fixation dramatically decreased to 0.10 ± 0.09 µmol m-3 d-1. The comparison with nitrate consumption and diffusion confirmed the minor role of N2 fixation (<1%) as a source of new N for primary production. The unicellular cyanobacterium UCYN-A2 was the dominant diazotroph during the cruise. UCYN-A2 abundance was four times higher during relaxation-downwelling (4x104 copies L-1) compared to upwelling conditions (0.2x104 copies L-1), when the unusual Epsilonproteobacteria increased their relative abundance. These results indicate that diazotrophs can respond rapidly to changes in the environment, and point out to the availability of N as a key factor controlling the activity, composition and distribution of diazotrophs in eutrophic regions

De Novo Lipogenesis in Adipose Tissue Is Associated with Course of Morbid Obesity after Bariatric Surgery

OBJECTIVE: De novo lipogenesis is involved in fatty acid biosynthesis and could be involved in the regulation of the triglyceride storage capacity of adipose tissue. However, the association between lipogenic and lipolytic genes and the evolution of morbidly obese subjects after bariatric surgery remains unknown. In this prospective study we analyze the association between the improvement in the morbidly obese patients as a result of bariatric surgery and the basal expression of lipogenic and lipolytic genes. METHODS: We study 23 non diabetic morbidly obese patients who were studied before and 7 months after bariatric surgery. Also, we analyze the relative basal mRNA expression levels of lipogenic and lipolytic genes in epiploic visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (SAT). RESULTS: When the basal acetyl-CoA carboxylase 1 (ACC1), acetyl-CoA synthetase 2 (ACSS2) and ATP citrate lyase (ACL) expression in SAT was below percentile-50, there was a greater decrease in weight (P = 0.006, P = 0.034, P = 0.026), body mass index (P = 0.008, P = 0.033, P = 0.034) and hip circumference (P = 0.033, P = 0.021, P = 0.083) after bariatric surgery. In VAT, when the basal ACSS2 expression was below percentile-50, there was a greater decrease in hip circumference (P = 0.006). After adjusting for confounding variables in logistic regression models, only the morbidly obese patients with SAT or VAT ACSS2 expression ≥ P50 before bariatric surgery had a lower percentage hip circumference loss (<P50) after bariatric surgery (SAT: P = 0.039; VAT: P = 0.033). CONCLUSIONS: A lower basal ACSS2, ACC1 and ACL expression, genes involved in de novo lipogenesis, is associated with a better evolution of anthropometric variables after bariatric surgery. Thus, the previous state of the pathways involved in fatty acid metabolism may have repercussions on the improvement of these patients