113 research outputs found

    The Geometric Maximum Traveling Salesman Problem

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    We consider the traveling salesman problem when the cities are points in R^d for some fixed d and distances are computed according to geometric distances, determined by some norm. We show that for any polyhedral norm, the problem of finding a tour of maximum length can be solved in polynomial time. If arithmetic operations are assumed to take unit time, our algorithms run in time O(n^{f-2} log n), where f is the number of facets of the polyhedron determining the polyhedral norm. Thus for example we have O(n^2 log n) algorithms for the cases of points in the plane under the Rectilinear and Sup norms. This is in contrast to the fact that finding a minimum length tour in each case is NP-hard. Our approach can be extended to the more general case of quasi-norms with not necessarily symmetric unit ball, where we get a complexity of O(n^{2f-2} log n). For the special case of two-dimensional metrics with f=4 (which includes the Rectilinear and Sup norms), we present a simple algorithm with O(n) running time. The algorithm does not use any indirect addressing, so its running time remains valid even in comparison based models in which sorting requires Omega(n \log n) time. The basic mechanism of the algorithm provides some intuition on why polyhedral norms allow fast algorithms. Complementing the results on simplicity for polyhedral norms, we prove that for the case of Euclidean distances in R^d for d>2, the Maximum TSP is NP-hard. This sheds new light on the well-studied difficulties of Euclidean distances.Comment: 24 pages, 6 figures; revised to appear in Journal of the ACM. (clarified some minor points, fixed typos

    Characterisation and evaluation of paramagnetic fluorine labelled glycol chitosan conjugates for 19F and 1H magnetic resonance imaging

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    Medium molecular weight glycol chitosan conjugates have been prepared, linked by an amide bond to paramagnetic Gd(III), Ho(III) and Dy(III) macrocyclic complexes in which a trifluoromethyl reporter group is located 6.5 Å from the paramagnetic centre. The faster relaxation of the observed nucleus allows modified pulse sequences to be used with shorter acquisition times. The polydisperse materials have been characterised by gel permeation chromatography, revealing an average molecular weight on the order of 13,800 (Gd), 14,600 (Dy) and 16,200 (Ho), consistent with the presence of 8.5, 9.5 and 13 complexes, respectively. The gadolinium conjugate was prepared for both a q = 1 monoamide tricarboxylate conjugate (r 1p 11.2 mM−1 s−1, 310 K, 1.4 T) and a q = 0 triphosphinate system, and conventional contrast-enhanced proton MRI studies at 7 T were undertaken in mice bearing an HT-29 or an HCT-116 colorectal tumour xenograft (17 μmol/kg). Enhanced contrast was observed following injection in the tail vein in tumour tissue, with uptake also evident in the liver and kidney with a tumour-to-liver ratio of 2:1 at 13 min, and large amounts in the kidney and bladder consistent with predominant renal clearance. Parallel experiments observing the 19F resonance in the holmium conjugate complex using a surface coil did not succeed owing to its high R 2 value (750 Hz, 7 T). However, the fluorine signal in the dysprosium triphosphinate chitosan conjugate [R 1/R 2 = 0.6 and R 1 = 145 Hz (7 T)] was sharper and could be observed in vivo at −65.7 ppm, following intravenous tail vein injection of a dose of 34 μmol/kg

    Complex X chromosome rearrangement associated with multiorgan autoimmunity

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    BACKGROUND: Turner syndrome, a congenital condition that affects 1/2,500 births, results from absence or structural alteration of the second sex chromosome. Turner syndrome is usually associated with short stature, gonadal dysgenesis and variable dysmorphic features. The classical 45,X karyotype accounts approximately for half of all patients, the remainder exhibit mosaicism or structural abnormalities of the X chromosome. However, complex intra-X chromosomal rearrangements involving more than three breakpoints are extremely rare. RESULTS: We present a unique case of a novel complex X chromosome rearrangement in a young female patient presenting successively a wide range of autoimmune diseases including insulin dependent diabetes mellitus, Hashimoto's thyroiditis, celiac disease, anaemia perniciosa, possible inner ear disease and severe hair loss. For the genetic evaluation, conventional cytogenetic analysis and FISH with different X specific probes were initially performed. The complexity of these results and the variety of autoimmune problems of the patient prompted us to identify the exact composition and breakpoints of the rearranged X as well as methylation status of the X chromosomes. The high resolution array-CGH (assembly GRCh37/hg19) detected single copy for the whole chromosome X short arm. Two different sized segments of Xq arm were present in three copies: one large size of 80,3 Mb from Xq11.1 to Xq27.3 region and another smaller (11,1 Mb) from Xq27.3 to Xq28 region. An 1,6 Mb Xq27.3 region of the long arm was present in two copies. Southern blot analysis identified a skewed X inactivation with approximately 70:30 % ratios of methylated/unmethylated fragments. The G-band and FISH patterns of the rearranged X suggested the aspect of a restructured i(Xq) chromosome which was shattered and fortuitously repaired. The X-STR genotype analysis of the family detected that the patient inherited intact maternal X chromosome and a rearranged paternal X chromosome. The multiple Xq breakages and fusions as well as inverted duplication would have been expected to cause a severe Turner phenotype. However, the patient lacks many of the classic somatic features of Turner syndrome, instead she presented multiorgan autoimmune diseases. CONCLUSIONS: The clinical data of the presented patient suggest that fragmentation of the i(Xq) chromosome elevates the risk of autoimmune diseases

    Paradoxical alteration of acute-phase protein levels in patients with chronic hepatitis C treated with IFN-alpha 2b

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    Previously we observed elevation of the serum concentration of two acute-phase protein (AFP) complement components (C9 and C1-inhibitor) in patients with chronic hepatitis C who responded (R) to IFN-alpha therapy, but not in non-responders (NR). In the present study we investigated the effect of high-dose IFN-alpha therapy on serum concentrations of two positive [orosomucoid (OROSO) and C-reactive protein (CRP)] and two negative [transferrin (TF) and fetuin/alpha2HS-glycoprotein (AHSG)] AFP in an outpatient setting. We investigated blood samples of 40 patients with chronic hepatitis C at the onset and at the end of a 3-month treatment with high-dose IFN-alpha2b (5 MIU/day for 6 weeks, followed by 5 MIU t.i.w.) and of 52 healthy individuals. Serum concentrations of OROSO, TF and AHSG were measured by radial immunodiffusion; CRP levels were determined by immunotubridimetry. Compared to controls, patients with chronic hepatitis C had significantly lower OROSO and CRP, and higher AHSG levels. By the end of treatment, OROSO concentration increased in R (P = 0.0054), but not in NR patients. In contrast, TF levels decreased in R (P = 0.0040), but did not change in NR patients. Similarly, in R patients, AHSG levels tended to decrease (P = 0.0942) following IFN-alpha treatment. We conclude that the acute-phase reaction is suppressed in patients with chronic hepatitis C that may be potentially related to the responsiveness to IFN-alpha therapy

    Chronic Activation of γ2 AMPK Induces Obesity and Reduces β Cell Function.

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    Despite significant advances in our understanding of the biology determining systemic energy homeostasis, the treatment of obesity remains a medical challenge. Activation of AMP-activated protein kinase (AMPK) has been proposed as an attractive strategy for the treatment of obesity and its complications. AMPK is a conserved, ubiquitously expressed, heterotrimeric serine/threonine kinase whose short-term activation has multiple beneficial metabolic effects. Whether these translate into long-term benefits for obesity and its complications is unknown. Here, we observe that mice with chronic AMPK activation, resulting from mutation of the AMPK γ2 subunit, exhibit ghrelin signaling-dependent hyperphagia, obesity, and impaired pancreatic islet insulin secretion. Humans bearing the homologous mutation manifest a congruent phenotype. Our studies highlight that long-term AMPK activation throughout all tissues can have adverse metabolic consequences, with implications for pharmacological strategies seeking to chronically activate AMPK systemically to treat metabolic disease

    OPTIMADE, an API for exchanging materials data

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    : The Open Databases Integration for Materials Design (OPTIMADE) consortium has designed a universal application programming interface (API) to make materials databases accessible and interoperable. We outline the first stable release of the specification, v1.0, which is already supported by many leading databases and several software packages. We illustrate the advantages of the OPTIMADE API through worked examples on each of the public materials databases that support the full API specification

    OPTIMADE, an API for exchanging materials data.

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    The Open Databases Integration for Materials Design (OPTIMADE) consortium has designed a universal application programming interface (API) to make materials databases accessible and interoperable. We outline the first stable release of the specification, v1.0, which is already supported by many leading databases and several software packages. We illustrate the advantages of the OPTIMADE API through worked examples on each of the public materials databases that support the full API specification

    Long -term feeding with high plant protein based diets in gilthead seabream (Sparus aurata, L.) leads to changes in the inflammatory and immune related gene expression at intestinal level

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    [EN] Background: In order to ensure sustainability of aquaculture production of carnivourous fish species such as the gilthead seabream (Sparus aurata, L.), the impact of the inclusion of alternative protein sources to fishmeal, including plants, has been assessed. With the aim of evaluating long-term effects of vegetable diets on growth and intestinal status of the on-growing gilthead seabream (initial weight = 129 g), three experimental diets were tested: a strict plant protein-based diet (VM), a fishmeal based diet (FM) and a plant protein-based diet with 15% of marine ingredients (squid and krill meal) alternative to fishmeal (VM+). Intestines were sampled after 154 days. Besides studying growth parameters and survival, the gene expression related to inflammatory response, immune system, epithelia integrity and digestive process was analysed in the foregut and hindgut sections, as well as different histological parameters in the foregut. Results: There were no differences in growth performance (p = 0.2703) and feed utilization (p = 0.1536), although a greater fish mortality was recorded in the VM group (p = 0.0141). In addition, this group reported a lower expression in genes related to pro-inflammatory response, as Interleukine-1 beta (il1 beta, p = 0.0415), Interleukine-6 (il6, p = 0.0347) and cyclooxigenase-2 (cox2, p = 0.0014), immune-related genes as immunoglobulin M (igm, p = 0.0002) or bacterial defence genes as alkaline phosphatase (alp, p = 0.0069). In contrast, the VM+ group yielded similar survival rate to FM (p = 0.0141) and the gene expression patterns indicated a greater induction of the inflammatory and immune markers (il1 beta, cox2 and igm). However, major histological changes in gut were not detected. Conclusions: Using plants as the unique source of protein on a long term basis, replacing fishmeal in aqua feeds for gilthead seabream, may have been the reason of a decrease in the level of different pro-inflammatory mediators (il1 beta, il6 and cox2) and immune-related molecules (igm and alp), which reflects a possible lack of local immune response at the intestinal mucosa, explaining the higher mortality observed. Krill and squid meal inclusion in vegetable diets, even at low concentrations, provided an improvement in nutrition and survival parameters compared to strictly plant protein based diets as VM, maybe explained by the maintenance of an effective immune response throughout the assay.The research has been partially funded by Vicerrectorat d'Investigacio, Innovacio i Transferencia of the Universitat Politecnica de Valencia, which belongs to the project Aquaculture feed without fishmeal (SP20120603). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.Estruch-Cucarella, G.; Collado, MC.; Monge-Ortiz, R.; Tomas-Vidal, A.; Jover Cerdá, M.; Peñaranda, D.; Perez Martinez, G.... (2018). Long -term feeding with high plant protein based diets in gilthead seabream (Sparus aurata, L.) leads to changes in the inflammatory and immune related gene expression at intestinal level. BMC Veterinary Research. 14. https://doi.org/10.1186/s12917-018-1626-6S14Hardy RW. Utilization of plant proteins in fish diets: effects of global demand and supplies of fishmeal. Aquac Res. 2010;41:770–6.Martínez-Llorens S, Moñino AV, Vidal AT, Salvador VJM, Pla Torres M, Jover Cerdá M, et al. Soybean meal as a protein source in gilthead sea bream (Sparus aurata L.) diets: effects on growth and nutrient utilization. Aquac Res. 2007;38(1):82–90.Tacon AGJ, Metian M. Global overview on the use of fish meal and fish oil in industrially compounded aquafeeds: trends and future prospects. Aquaculture. 2008;285:146–58.Bonaldo A, Roem AJ, Fagioli P, Pecchini A, Cipollini I, Gatta PP. Influence of dietary levels of soybean meal on the performance and gut histology of gilthead sea bream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.). Aquac Res. 2008;39(9):970–8.Kissil G, Lupatsch I. Successful replacement of fishmeal by plant proteins in diets for the gilthead seabream, Sparus Aurata L. Isr J Aquac – Bamidgeh. 2004;56(3):188–99.Monge-Ortíz R, Martínez-Llorens S, Márquez L, Moyano FJ, Jover-Cerdá M, Tomás-Vidal A. Potential use of high levels of vegetal proteins in diets for market-sized gilthead sea bream (Sparus aurata). Arch Anim Nutr. 2016;70(2):155–72.Santigosa E, Sánchez J, Médale F, Kaushik S, Pérez-Sánchez J, Gallardo MA. Modifications of digestive enzymes in trout (Oncorhynchus mykiss) and sea bream (Sparus aurata) in response to dietary fish meal replacement by plant protein sources. Aquaculture. 2008;282:68–74.Santigosa E, García-Meilán I, Valentin JM, Pérez-Sánchez J, Médale F, Kaushik S, et al. Modifications of intestinal nutrient absorption in response to dietary fish meal replacement by plant protein sources in sea bream (Sparus aurata) and rainbow trout (Onchorynchus mykiss). Aquaculture. 2011;317:146–54.Sitjá-Bobadilla A, Peña-Llopis S, Gómez-Requeni P, Médale F, Kaushik S, Pérez-Sánchez J. Effect of fish meal replacement by plant protein sources on non-specific defence mechanisms and oxidative stress in gilthead sea bream (Sparus aurata). Aquaculture. 2005;249:387–400.Martínez-Llorens S, Baeza-Ariño R, Nogales-Mérida S, Jover-Cerdá M, Tomás-Vidal A. Carob seed germ meal as a partial substitute in gilthead sea bream (Sparus aurata) diets: amino acid retention, digestibility, gut and liver histology. Aquaculture. 2012;338-341:124–33.Baeza-Ariño R, Martínez-Llorens S, Nogales-Mérida S, Jover-Cerda M, Tomás-Vidal A. Study of liver and gut alterations in sea bream, Sparus aurata L., fed a mixture of vegetable protein concentrates. Aquac Res. 2014;47(2):460–71.Estruch G, Collado MC, Peñaranda DS, Tomás Vidal A, Jover Cerdá M, Pérez Martínez G, et al. Impact of fishmeal replacement in diets for gilthead sea bream (Sparus aurata) on the gastrointestinal microbiota determined by pyrosequencing the 16S rRNA gene. PLoS One. 2015;10(8):e0136389. https://doi.org/10.1371/journal.pone.0136389 .Fekete SG, Kellems RO. Interrelationship of feeding with immunity and parasitic infection: a review. Vet Med. 2007;52(4):131–43.Kiron V. Fish immune system and its nutritional modulation for preventive health care. Anim Feed Sci Technol. 2012;173(1–2):111–33.Minghetti M, Drieschner C, Bramaz N, Schug H, Schirmer K. A fish intestinal epithelial barrier model established from the rainbow trout (Oncorhynchus mykiss) cell line, RTgutGC. Cell Biol Toxicol. 2017;33:539–55.Cerezuela R, Meseguer J, Esteban MÁ. Effects of dietary inulin, Bacillus subtilis and microalgae on intestinal gene expression in gilthead seabream (Sparus aurata L.). Fish Shellfish Immunol. 2013;34(3):843–8.Couto A, Kortner TM, Penn M, Bakke AM, Krogdahl O-TA, et al. Effects of dietary soy saponins and phytosterols on gilthead sea bream (Sparus aurata) during the on-growing period. Anim Feed Sci Technol. 2014;198:203–14.Estensoro I, Calduch-Giner JA, Kaushik S, Pérez-Sánchez J, Sitjá-Bobadilla A. Modulation of the IgM gene expression and IgM immunoreactive cell distribution by the nutritional background in gilthead sea bream (Sparus aurata) challenged with Enteromyxum leei (Myxozoa). Fish Shellfish Immunol. 2012;33(2):401–10.Pérez-Sánchez J, Estensoro I, Redondo MJ, Calduch-Giner JA, Kaushik S, Sitjà-Bobadilla A. Mucins as diagnostic and prognostic biomarkers in a fish-parasite model: transcriptional and functional analysis. PLoS One. 2013;8(6):e65457.Reyes-Becerril M, Guardiola F, Rojas M, Ascencio-Valle F, Esteban MÁ. Dietary administration of microalgae Navicula sp. affects immune status and gene expression of gilthead seabream (Sparus aurata). Fish Shellfish Immunol. 2013;35(3):883–9.Pérez-Sánchez J, Benedito-Palos L, Estensoro I, Petropoulos Y, Calduch-Giner JA, Browdy CL, et al. Effects of dietary NEXT ENHANCE ® 150 on growth performance and expression of immune and intestinal integrity related genes in gilthead sea bream (Sparus aurata L.). Fish Shellfish Immunol. 2015;44:117–28.Estensoro I, Ballester-Lozano G, Benedito-Palos L, Grammes F, Martos-Sitcha JA, Mydland L-T, et al. Dietary butyrate helps to restore the intestinal status of a marine teleost (Sparus aurata) fed extreme diets low in fish meal and fish oil. PLoS One. 2016;11(11):1–21.Torrecillas S, Caballero MJ, Mompel D, Montero D, Zamorano MJ, Robaina L, et al. Disease resistance and response against Vibrio anguillarum intestinal infection in European seabass (Dicentrarchus labrax) fed low fish meal and fish oil diets. Fish Shellfish Immunol. 2017;67:302–11.Schmittgen TD, Livak KJ. Analyzing real-time PCR data by the comparative C T method. Nat Protoc. 2008;3(6):1101–8.Omnes MH, Silva FCP, Moriceau J, Aguirre P, Kaushik S, Gatesoupe F-J. Influence of lupin and rapeseed meals on the integrity of digestive tract and organs in gilthead seabream (Sparus aurata L.) and goldfish (Carassius auratus L.) juveniles. Aquac Nutr. 2015;21:223–33.Francis G, Makkar HPS, Becker K. Antinutritional factors present in plant-derived alternate fish feed ingredients and their effects in fish. Aquaculture. 2001;199:197–227.Gatlin DM III, Barrows FT, Brown P, Dabrowski K, Gaylord TG, Hardy RW, et al. Expanding the utilization of sustainable plant products in aquafeeds: a review. Aquac Res. 2007;38:551–79.Kader MA, Bulbul M, Koshio S, Ishikawa M, Yokoyama S, Nguyen BT, et al. Effect of complete replacement of fishmeal by dehulled soybean meal with crude attractants supplementation in diets for red sea bream, Pagrus major. Aquaculture. 2012;350-353:109–16.Gómez-Requeni P, Mingarro M, Calduch-Giner JA, Médale F, Martin SAM, Houlihan DF, et al. Protein growth performance, amino acid utilisation and somatotropic axis responsiveness to fish meal replacement by plant protein sources in gilthead sea bream (Sparus aurata). Aquaculture. 2004;232(1–4):493–510.Kader MA, Koshio S, Ishikawa M, Yokoyama S, Bulbul M. Supplemental effects of some crude ingredients in improving nutritive values of low fishmeal diets for red sea bream, Pagrus major. Aquaculture. 2010;308(3–4):136–44.Mai K, Li H, Ai Q, Duan Q, Xu W, Zhang C, et al. Effects of dietary squid viscera meal on growth and cadmium accumulation in tissues of Japanese seabass, Lateolabrax japonicus (Cuvier 1828). Aquac Res. 2006;37(11):1063–9.Peres H, Oliva-Teles A. The optimum dietary essential amino acid profile for gilthead seabream (Sparus aurata) juveniles. Aquaculture. 2009;296(1–2):81–6.Cho CY, Slinger SJ, Bayley HS. Bioenergetics of salmonid fishes: energy intake, expenditure and productivity. Comp Biochem Physiol Part B. 1982;73(1):25–41.Venou B, Alexis MN, Fountoulaki E, Haralabous J. Effects of extrusion and inclusion level of soybean meal on diet digestibility , performance and nutrient utilization of gilthead sea bream ( Sparus aurata ). Aquaculture. 2006;261:343–56.Pfaffl MW, Tichopad A, Prgomet C, Neuvians TP. Determination of stable housekeeping genes, differentially regulated target genes and sample integrity: BestKeeper-excel-based tool using pair-wise correlations. Biotechnol Lett. 2004;26:509–15.Terova G, Robaina L, Izquierdo M, Cattaneo A, Molinari S, Bernardini G, et al. PepT1 mRNA expression levels in sea bream (Sparus aurata) fed different plant protein sources. Springerplus. 2013;2:17.Bates JM, Akerlund J, Mittge E, Guillemin K. Intestinal alkaline phosphatase detoxifies lipopolysaccharide and prevents inflammation in zebrafish in response to the gut microbiota. Cell Host Microbe. 2007;2(6):371–82.Adamidou S, Nengas I, Henry M, Grigorakis K, Rigos G, Nikolopoulou D, et al. Growth, feed utilization, health and organoleptic characteristics of European seabass (Dicentrarchus labrax) fed extruded diets including low and high levels of three different legumes. Aquaculture. 2009;293(3–4):263–71.Daprà F, Gai F, Costanzo MT, Maricchiolo G, Micale V, Sicuro B, et al. Rice protein-concentrate meal as a potential dietary ingredient in practical diets for blackspot seabream Pagellus bogaraveo: a histological and enzymatic investigation. J Fish Biol. 2009;74(4):773–89.Overland M, Sorensen M, Storebakken T, Penn M, Krogdahl A, Skrede A. Pea protein concentrate substituting fish meal or soybean meal in diets for Atlantic salmon (Salmo salar)-effect on growth performance, nutrient digestibility, carcass composition, gut health, and physical feed quality. Aquaculture. 2009;288(3–4):305–11.Penn MH, Bendiksen EA, Campbell P, Krogdahl AS. High level of dietary pea protein concentrate induces enteropathy in Atlantic salmon (Salmo salar L.). Aquaculture. 2011;310(3–4):267–73.Hedrera MI, Galdames JA, Jimenez-Reyes MF, Reyes AE, Avendaño-Herrera R, Romero J, et al. Soybean meal induces intestinal inflammation in zebrafish larvae. PLoS One. 2013;8(7):1–10.Kokou F, Sarropoulou E, Cotou E, Rigos G, Henry M, Alexis M. Effects of fish meal replacement by a soybean protein on growth, histology, selected immune and oxidative status markers of Gilthead Sea bream, Sparus aurata. J World Aquac Soc. 2015;46(2):115–28.Kokou F, Sarropoulou E, Cotou E, Kentouri M, Alexis M, Rigos G. Effects of graded dietary levels of soy protein concentrate supplemented with methionine and phosphate on the immune and antioxidant responses of gilthead sea bream (Sparus aurata L.). Fish Shellfish Immunol. 2017;64:111–21.Calduch-Giner JA, Sitjà-Bobadilla A, Davey GC, Cairns MT, Kaushik S, Pérez-Sánchez J. Dietary vegetable oils do not alter the intestine transcriptome of gilthead sea bream (Sparus aurata), but modulate the transcriptomic response to infection with Enteromyxum leei. BMC Genomics. 2012;13(1):470.Piazzon MC, Galindo-Villegas J, Pereiro P, Estensoro I, Calduch-Giner JA, Gómez-Casado E, et al. Differential modulation of IgT and IgM upon parasitic, bacterial, viral, and dietary challenges in a perciform fish. Front Immunol. 2016;7. Article 637. https://doi.org/10.3389/fimmu.2016.00637 .Salinas I, Zhang Y, Sunyer JO. Mucosal immunoglobulins and B cells of teleost fish. Dev Comp Immunol. 2011;35(12):1346–65.Krogdahl A, Bakke-McKellep AM, Roed KH, Baeverfjord G. Feeding Atlantic salmon Salmo salar L. soybean products: effects on disease resistance (furunculosis), and lysozyme and IgM levels in the intestinal mucosa. Aquac Nutr. 2000;6:77–84.Chasiotis H, Effendi JC, Kelly SP. Occludin expression in goldfish held in ion-poor water. J Comp Physiol B Biochem Syst Environ Physiol. 2009;179(2):145–54.Chen KT, Malo MS, Beasley-Topliffe LK, Poelstra K, Millan JL, Mostafa G, et al. A role for intestinal alkaline phosphatase in the maintenance of local gut immunity. Dig Dis Sci. 2011;56(4):1020–7.Vaishnava S, Hooper LV. Alkaline phosphatase: keeping the peace at the gut epithelial surface. Cell Host Microbe. 2007;2(6):365–7.Tort L. Stress and immune modulation in fish. Dev Comp Immunol [internet]. Elsevier Ltd. 2011;35(12):1366–75.Martin SAM, Król E. Nutrigenomics and immune function in fish: new insights from omics technologies. Dev Comp Immunol. 2017;75:86–98.Burrells C, Williams PD, Southgate PJ, Crampton VO. Immunological , physiological and pathological responses of rainbow trout (Oncorhynchus mykiss) to increasing dietary concentrations of soybean proteins. Vet Immunol Immunopathol. 1999;72:277–88.Sahlmann C, Sutherland BJG, Kortner TM, Koop BF, Krogdahl Å, Bakke AM. Early response of gene expression in the distal intestine of Atlantic salmon (Salmo salar L.) during the development of soybean meal induced enteritis. Fish Shellfish Immunol. 2013;34(2):599–609.Esteban MÁ, Cuesta A, Ortuño J, Meseguer J. Immunomodulatory effects of dietary intake of chitin on gilthead seabream ( Sparus aurata L .) innate immune system. Fish Shellfish Immunol. 2001;11:303–15.Storebakken T, Kvien IS, Shearer KD, Grisdale-Helland B, Helland SJ. Estimation of gastrointestinal evacuation rate in Atlantic salmon (Salmo salar) using inert markers and collection of faeces by sieving: evacuation of diets with fish meal, soybean meal or bacterial meal. Aquaculture. 1999;172(3–4):291–9.Olsen RE, Myklebust R, Ringø E, Mayhew TM. The influences of dietary linseed oil and saturated fatty acids on caecal enterocytes in Arctic char (Salvelinus alpinus L.): a quantitative ultrastructural study. Fish Physiol Biochem. 2000;22(3):207–16.Heikkinen J, Vielma J, Kemiläinen O, Tiirola M, Eskelinen P, Kiuru T, et al. Effects of soybean meal based diet on growth performance, gut histopathology and intestinal microbiota of juvenile rainbow trout (Oncorhynchus mykiss). Aquaculture. 2006;261(1):259–68.Krogdahl A, Bakke-McKellep AM, Baeverfjord G. Effects of graded levels of standard soybean meal on intestinal structure, mucosal enzyme activities, and pancreatic response in Atlantic salmon (Salmo salar L.). Aquac Nutr. 2003;9:361–71.Cerezuela R, Fumanal M, Tapia-Paniagua ST, Meseguer J, Moriñigo MA, Esteban MA. Changes in intestinal morphology and microbiota caused by dietary administration of inulin and Bacillus subtilis in gilthead sea bream (Sparus aurata L.) specimens. Fish Shellfish Immunol. 2013;34(5):1063–70.Cerezuela R, Fumanal M, Tapia-Paniagua ST, Meseguer J, Moriñigo MÁ, Esteban MÁ. Histological alterations and microbial ecology of the intestine in gilthead seabream (Sparus aurata L.) fed dietary probiotics and microalgae. Cell Tissue Res. 2012;350(3):477–89.Deplancke B, Gaskins HR. Microbial modulation of innate defense: goblet cells and the intestinal mucus layer. Am J Clin Nutr. 2001;73(suppl):1131S–41S.Kokou F, Rigos G, Henry M, Kentouri M, Alexis M. Growth performance, feed utilization and non-specific immune response of gilthead sea bream (Sparus aurata L.) fed graded levels of a bioprocessed soybean meal. Aquaculture. 2012;364-365:74–81

    Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

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    The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
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