The role of angular momentum in the construction of electromagnetic multipolar fields

Multipolar solutions of Maxwell's equations are used in many practical applications and are essential for the understanding of light-matter interactions at the fundamental level. Unlike the set of plane wave solutions of electromagnetic fields, the multipolar solutions do not share a standard derivation or notation. As a result, expressions originating from different derivations can be difficult to compare. Some of the derivations of the multipolar solutions do not explicitly show their relation to the angular momentum operators, thus hiding important properties of these solutions. In this article, the relation between two of the most common derivations of this set of solutions is explicitly shown and their relation to the angular momentum operators is exposed.Comment: 13 pages, 2 figure

Impact of Dietary Supplementation with Sodium Butyrate Protected by Medium-Chain Fatty Acid Salts on Gut Health of Broiler Chickens

This research was co-funded by the European Fund of Regional Development of the European Union within the framework of the FEDER operating program of Catalunya 2014-2020 (project COMRDI16-1-0033) and managed by ACCIÓ.Nutritional strategies to improve gut health of broilers are under research. This study investigated the effect of dietary supplementation with sodium butyrate protected by sodium salts of medium-chain fatty acids as a feed additive on broiler gut health. The first experiment was conducted to evaluate the effect of supplementing at 0.5, 1, and 2 kg/t in broilers housed under optimal conditions. Supplementation at 0.5 and 1 kg/t maintained goblet cell counts at 10 days of age (p ≤ 0.05), and supplementation at 1 kg/t decreased intraepithelial lymphocyte counts compared to 2 kg/t at 39 days (p ≤ 0.10). Abdominal fat pad levels of lauric and myristic acids were gradually increased by supplement dose (p ≤ 0.05). In the second experiment, the feed additive at 1 kg/t was evaluated in coccidiosis-challenged broilers. Experimental treatments were as follows: non-challenged, control-challenged, and supplemented-challenged treatments. Coccidiosis negatively impact performance and modify histomorphometry and microbiota (p ≤ 0.05). The feed additive increased crypt depth at 7 days post-inoculation and goblet cell count at 14 days post-inoculation (p ≤ 0.05). Further, supplementation interacted with the microbiota modification led by the coccidiosis (p ≤ 0.05). These results suggest that this feed additive could be a useful strategy to reinforce the gut barrier, especially for birds under coccidiosis-challenge treatments

A comparative study of an ad libitum integral feeding system and other conventional system with ad libitum forage and concentrate on ration separately in Rasa Aragonesa ewes

En una explotación semiextensiva de Rasa Aragonesa, 64 ovejas con sus corderos de parto simple fueron distribuidas aleatoriamente en dos grupos tras el parto de acuerdo a dos sistemas de alimentación: un sistema integral ad libitum en forma de paca, 50% paja, 50% concentrado (grupo RUM), frente a otro convencional con paja de cereal ad libitum y por separado el mismo concentrado racionado dos veces al día (grupo FORR+CONCE). A los corderos se les proporcionó harina de iniciación y pienso de arranque. La experiencia duró desde el parto hasta el destete (43±3 d) y los consumos ad libitum del lote RUM fueron de 1,8 kg de MF oveja/día y de 1,73 kg (paja y concentrado) en el lote FORR+CONCE, resultando en la práctica equivalentes nutricionalmente. Los corderos del lote RUM tendieron a presentar una mayor ganancia media diaria (214 vs. 196 g/día; P<0,07) y una mortalidad menor (3,1% vs 12,5%), aunque no significativas. Respecto al efecto de la movilización de reservas de las ovejas, el lote RUM redujo 1 kg su peso vivo frente a 2,2 kg el lote FORR+CONCE. El coste bruto de la alimentación (sin valorar la mano de obra) en lote RUM fue +0,056 €/oveja/día, pero si se incluye el efecto de movilización de reservas se reduce a +0,030 y si se incorpora el efecto mortalidad corderos queda finalmente en -0,079 €/oveja/díaIn a semi-extensive farm of Rasa Aragonesa breed, sixty four single lambs and their dams were randomly allocated in two groups according to two feeding systems: an integral feeding system ad libitum in form of bales (50% straw, 50% concentrate) (group RUM) was compared to a convencional system (group FORR+CONCE) receiving equal amount of concentrate twice a day and straw ad libitum. Lambs had free access to starter flour and concentrate. The study was performed from birth to weaning (43±3), RUM intake ad libitum and FORR+CONCE intake (straw and concentrate) were 1.8 and 1.73 kg FM ewe/d respectively, similar nutritional facts. RUM lambs tended to show a greater daily gain had a tendency to greater daily gain (214 vs. 196 g/d; P<0.07) and the lower mortality (3.1% vs. 12.5%), although significance was not achieved. Respect to the evolution of body weight, RUM and FORR+CONCE groups decreased 1 and 2,2 kg respectively. The integral feeding gross cost (without labour cost) was higher in RUM group +0.056 €/ ewe/d, however, valuing body weight decreases to +0.030 and finally including lamb mortality was -0.079 €/ ewe/d.Al Centro de Transferencias Agroalimentarias del Departamento de Agricultura y Alimentación del Gobierno de Aragón que ha financiado parte del proyecto que incluye este estudio DER- 2009-02-50-720205-55

Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets

Background: The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties, such as medium-chain fatty acids (MCFA) as in-feed additives. This study evaluated the potential of a novel blend of MCFA salts (DIC) from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning. Two experimental disease models were implemented in early-weaned piglets, consisting of two oral challenges: Salmonella Typhimurium (1.2 × 10 CFU) or enterotoxigenic Escherichia coli (ETEC) F4 (1.5 × 10 CFU). The parameters assessed were: animal performance, clinical signs, pathogen excretion, intestinal fermentation, immune-inflammatory response, and intestinal morphology. Results: The Salmonella challenge promoted an acute course of diarrhea, with most of the parameters responding to the challenge, whereas the ETEC F4 challenge promoted a mild clinical course. A consistent antipathogenic effect of DIC was observed in both trials in the hindgut, with reductions in Salmonella spp. plate counts in the cecum (P = 0.03) on d 8 post-inoculation (PI) (Salmonella trial), and of enterobacteria and total coliform counts in the ileum and colon (P < 0.10) on d 8 PI (ETEC F4 trial). When analyzing the entire colonic microbiota (16S rRNA gene sequencing), this additive tended (P = 0.13) to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge. In the ETEC F4 challenge, DIC prompted structural changes in the ecosystem with increases in Dialister, and a trend (P = 0.14) to increase the Veillonellaceae family. Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation, nor were the histological parameters. Only the intraepithelial lymphocyte (IEL) counts were lowered by DIC in animals challenged with Salmonella (P = 0.07). With ETEC F4, the IEL counts were higher with DIC on d 8 PI (P = 0.08). Conclusions: This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E. coli and its ability to modulate colonic microbiota. These changes could explain to some extent the local immune cell response at the ileal level

Five recommendations to accelerate sustainable solutions in cement and concrete through partnership

Though the technical knowledge to make cement and concrete more sustainable already exists, implementation of solutions lags behind the rate needed to mitigate climate change and meet the targets set by the Sustainable Development Goals. Whilst most of the focus around the built environment is on embodied carbon, we stress an important but neglected dimension: partnership (SDG17). Effective partnerships can be powerful enablers to accelerate sustainable solutions in cement and concrete, and let such solutions transfer from academia to the market. This can be achieved through knowledge generation, solution implementation, and policy development, among other routes. In this article, we share five recommendations for how partnerships can address neglected research questions and practical needs: 1) reform Science, Technology, Engineering and Mathematics (STEM) education to train “circular citizens”; 2) map out routes by which cementitious materials can contribute to a “localization” agenda; 3) generate open‐access maps for the geographical distribution of primary and secondary raw materials; 4) predict the long‐term environmental performance of different solutions for low‐CO2 cements in different geographical areas; 5) overhaul standards to be technically and regionally fit for purpose. These approaches have the potential to make a unique and substantial contribution towards achieving collective sustainability goals

Bio-Assisted Tailored Synthesis of Plasmonic Silver Nanorings and Site-Selective Deposition on Graphene Arrays

The spontaneous interaction between noble metals and biological scaffolds enables simple and cost-effective synthesis of nanomaterials with unique features. Here, plasmonic silver nanorings are synthesized on a ring-like protein, i.e., a peroxiredoxin (PRX), and used to assemble large arrays of functional nanostructures. The PRX drives the seeding growth of metal silver under wet reducing conditions, yielding nanorings with outer and inner diameters down to 28 and 3 nm, respectively. The obtained hybrid nanostructures are selectively deposited onto a solid-state 2D membrane made of graphene in order to prepare plasmonic nanopores. In particular, the interaction between the graphene and the PRX allows for the simple preparation of ordered arrays of plasmonic nanorings on a 2D-material membrane. This fabrication process can be finalized by drilling a nanometer scale pore in the middle of the ring. Fluorescence spectroscopic measurements in combination with numerical simulations demonstrate the plasmonic effects induced in the metallic nanoring cavity. The prepared nanopores represent one of the first examples of hybrid plasmonic nanopore structures integrated on a 2D-material membrane. The diameter of the nanopore and the atomically thick substrate make this proof-of-concept approach particularly interesting for nanopore-based technologies and applications such as next-generation sequencing and single-molecule detection

Behavioural changes in weaned piglets orally challenged with Escherichia coli F4 and supplemented with in-feed protected acid salts

Altres ajuts: acords transformatius de la UABImprovement of the intestinal health of piglets at weaning is a principal objective in pig farming in terms of performance and welfare benefits. Early indicators of disease are indispensable for evaluating animal health and the efficacy of interventions such as feed additive supplementation. This study evaluates behavioural changes in weaned piglets that are orally challenged with enterotoxigenic Escherichia coli F4, and which receive or not two different in-feed additives. Two independent trials were performed with early-weaned piglets in pens of three animals, which were fed a plain diet (N = 32) or one supplemented with sodium butyrate (N = 16; Trial 1) or sodium heptanoate (N = 16; Trial 2) and protected with coconut distillates. After one week of adaptation, piglets were challenged with a single oral dose of E. coli F4 (minimum 1.4 x109 cfu). Scan-sampling was used to evaluate individual behaviour (location in the pen, postures, contact with pen mates, and activities) on the day before (d-1) and two days post-inoculation (d+2 and d+3) at 2-min intervals. Behaviours were recorded in mornings (8 am to 10 am) and afternoons (4 pm to 6 pm). Faecal consistency was also recorded for each animal. Diarrhoea peaked at d+ 2. Regarding behaviour, on d+ 2 there was greater frequency of the animals lying inactively under the heat lamp, in contrast to d-1 when they were more frequently present in the feeder, standing and active (P < 0.05). Around the feeder, standing and active behaviour increased at d+ 3, especially in the afternoon (PDayxTime of day < 0.05). Piglets fed sodium heptanoate spent less time around the feeder (P < 0.05). The weight of the animal at weaning was also observed to have an impact on the effect of time or diet on behaviour. Medium size piglets spent more time lying with pen mates in the afternoon (PSizexTime of day < 0.01) and the smallest piglets increased their feeding behaviour when receiving the supplemented diets (PSizexDiet < 0.05). In conclusion, a lethargic response among piglets after the E. coli F4 challenge was evidenced, this response being slightly modified by the supplementation of in-feed additives and the size of the animals. These results are evidence of the potential of behavioural indicators as a useful tool to assess the health status of piglets at weaning and their responses to in-feed supplementation, but they should be regarded with caution before any transfer to farm conditions due to the limitations of experimental models

Frailty is associated with objectively assessed sedentary behaviour patterns in older adults: Evidence from the Toledo Study for Healthy Aging (TSHA)

Objective: The aim of this study was to examine the association of sedentary behaviour patterns with frailty in older people. Setting: Clinical setting. Design: Cross-sectional, observational study. Participants and measurements: A triaxial accelerometer was used in a subsample from the Toledo Study for Healthy Aging (519 participants, 67–97 years) to assess several sedentary behaviour patterns including sedentary time per day, the number and duration (min) of breaks in sedentary time per day, and the proportion of the day spent in sedentary bouts of 10 minutes or more. Frailty was assessed using the Frailty Trait Scale (FTS). Regression analysis was used to ascertain the associations between sedentary behaviour patterns and frailty. Results: Sedentary time per day and the proportion of the day spent in sedentary bouts of 10 minutes or more, were positively associated with frailty in the study sample. Conversely, the time spent in breaks in sedentary time was negatively associated with frailty. Conclusion: In summary, breaking up sedentary time and time spent in sedentary behaviour are associated with frailty in older people

Electromagnetic duality symmetry and helicity conservation for the macroscopic Maxwell's equations (previously "Experimental demonstration of electromagnetic duality symmetry breaking")

Modern physics is largely devoted to study conservation laws, such as charge, energy, linear momentum or angular momentum, because they give us information about the symmetries of our universe. Here, we propose to add the relationship between electromagnetic duality and helicity to the toolkit. Generalized electromagnetic duality symmetry, broken in the microscopic Maxwell's equations by the empirical absence of magnetic charges, can be restored for the macroscopic Maxwell's equations. The restoration of this symmetry is shown to be independent of the geometry of the problem. These results provide a simple and powerful tool for the study of light-matter interactions within the framework of symmetries and conservation laws. We apply such framework to the experimental investigation of helicity transformations in cylindrical nanoapertures, and we find that the transformation is significantly enhanced by the coupling to surface modes, where electromagnetic duality is strongly broken.Comment: 26 pages, 4 figure

Rendimiento del MOET aplicado al programa de selección de la Rasa Aragonesa de UPRA-Grupo Pastores

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