Investigations on the effects of internal liquid sloshing of semi-submersible floating offshore wind turbines

Originally developed for civil engineering applications, the tuned liquid column damper (TLCD) has been applied not only on tall buildings but also on floating offshore wind turbines (FOWTs) to minimize structural vibrations. This concept has also been adopted widely in navel architecture to reduce the roll motion. However, whether the damper will bring positive effects on mitigating the dynamic motions of FOWTs remains unknown. To this end, the paper studies the star-like three columns tuned liquid multi-column damper (TLMCD) impacts on the dynamic motions of a semi-submersible FOWT. The modelling is achieved by using a high-fidelity computational fluid dynamic (CFD) solver based on OpenFOAM. After the verification of the numerical model for the TLMCD system, it is extended to the modelling of the internal sloshing of TLMCD under prescribed pitch motions. A fully coupled floating-sloshing modelling is then conducted to simulate a semi-submersible FOWT with an integrated TLMCD under regular wave conditions. The study indicates that the passive-control TLMCD system has nearly no influence on the translational motions such as surge and heave. However, the pitch motions can be reduced significantly when the incident wave frequency is close to the natural pitch frequency of the platform. Apart from the natural pitch frequency, the TLMCD has a minor effect at other incident wave frequencies

Performance and fatigue analysis of an integrated floating wind-current energy system considering the aero-hydro-servo-elastic coupling effects

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Effects of dietary supplementation of trans-anethole on the intestinal antioxidant status, immune function, and liver lipid metabolism in broilers

This study was aimed to investigate the effects of trans-anethole (TA) on intestinal antioxidant status, immune function and liver lipid metabolism in broilers. A total of 256 1-day-old Arbour Acres broilers were allocated to 4 treatment groups with 8 birds per replicate. TA was added to diets at a concentration of 0 (control), 400, 600, and 800 mg/kg for 42 days. Dietary supplementation of TA increased the average daily feed intake (ADFI) of birds throughout the entire period. TA supplemented at 400 mg/kg of diet contributed to the lowest jejunal and ileal malondialdehyde (MDA) concentration on d 42, and the highest ileal total superoxide dismutase (T-SOD) activity on d 21 and d 42. TA supplementation at the concentration of 400 and 600 mg/kg of diet increased mRNA expression of ileal interleukin (IL)-4 on d 21, and intestinal secretory immunoglobulin A (sIgA) concentration on d 42. Supplementation of TA at the concentration up to 800 mg/kg of diet had adverse effects on intestinal antioxidant status, immune function and liver lipid metabolism compared with control group. Differently, TA supplemented at 400 mg/kg led to lower mRNA expression of liver ACC1, FASN, sterol regulatory element-binding protein 1c (SREBP-1), and higher CPT1 on d 42. In conclusion, TA inclusion improved intestinal antioxidant status and immune function, and enhanced liver lipid metabolism of broilers.HIGHLIGHTS Supplementation of 400 mg/kg of TA increased intestinal antioxidant status and immune function, and promoted liver lipid metabolism of broilers compared with non-supplemented group

Pharmacological Effects of Polyphenol Phytochemicals on the Intestinal Inflammation via Targeting TLR4/NF-κB Signaling Pathway

TLR4/NF-κB is a key inflammatory signaling transduction pathway, closely involved in cell differentiation, proliferation, apoptosis, and pro-inflammatory response. Toll like receptor 4 (TLR4), the first mammalian TLR to be characterized, is the innate immune receptor that plays a key role in inflammatory signal transductions. Nuclear factor kappa B (NF-κB), the TLR4 downstream, is the key to accounting for the expression of multiple genes involved in inflammatory responses, such as pro-inflammatory cytokines. Inflammatory bowel disease (IBD) in humans is a chronic inflammatory disease with high incidence and prevalence worldwide. Targeting the TLR4/NF-κB signaling pathway might be an effective strategy to alleviate intestinal inflammation. Polyphenol phytochemicals have shown noticeable alleviative effects by acting on the TLR4/NF-κB signaling pathway in intestinal inflammation. This review summarizes the pharmacological effects of more than 20 kinds of polyphenols on intestinal inflammation via targeting the TLR4/NF-κB signaling pathway. We expected that polyphenol phytochemicals targeting the TLR4/NF-κB signaling pathway might be an effective approach to treat IBD in future clinical research applications

Effect of different sources and levels of iron in the diet of sows on iron status in neonatal pigs

This study was conducted to determine the effects of maternal dietary supplementation of ferrous glycine chelate (Fe-Gly) and ferrous sulfate monohydrate (FeSO4·H2O) on the relative organ weight, tissue iron contents, red blood cells (RBC), hemoglobin concentration (HGB) and hematocrit (HCT) in blood, as well as ferritin (Fn), serum iron (SI), and total iron binding capacity (TIBC) in serum of newborn piglets. Forty-five sows (Landrace × Large white, mean parity 3 to 4, no significant differences in BW) were randomly allotted to 9 treatments (n = 5 sows/treatment): control (basal diet with no Fe supplementation), the basal diet supplemented with 50, 80, 110 or 140 mg Fe/kg as Fe-Gly, and the basal diet supplemented with 50, 80, 110 or 140 mg Fe/kg as FeSO4·H2O. The neonatal piglets (n = 45) were used to determine the relative organ weight, tissue iron contents and blood biochemical indices. Compared with the control, the relative weight of spleen and kidney were significantly increased (P < 0.05) in the Fe-Gly groups. The iron contents in liver, spleen, kidney and femur were also found increased (P < 0.05) in the Fe-Gly groups. The RBC (d 1 and 21), HGB (d 1 and 21) and HCT (d 1 and 21) in blood and Fn (d 1) and SI (d 1 and 21) significantly increased (P < 0.05), but the TIBC (d 1 and 21) in serum decreased (P < 0.05) in the Fe-Gly groups. Moreover, the kidney relative weight, iron content in liver, spleen, kidney and femur, RBC (d 1) and HGB (d 21) in blood, and SI (d 1) in the Fe-Gly groups increased (P < 0.05) compared with the FeSO4·H2O treatment. Linear and quadratic responses of the kidney relative weight, the iron content in liver, spleen, kidney and femur, RBC (d 1 and 21), HGB (d 1 and 21) and HCT (d 1 and 21) in whole blood, SI (d 1) and TIBC (d 1 and 21) in the Fe-Gly groups were observed (P < 0.05). Linear responses of Fn (d 1 and 21) and SI (d 21) in the Fe-Gly groups, and spleen relative weight, HCT (d 1), Fn (d 1) and TIBC (d 1 and 21) in the FeSO4·H2O groups were observed (P < 0.05). These finding suggest that Fe-Gly supplemented at the level of 110 mg/kg in the diet of sows in this experiment is superior to other forms of supplementation, based on HGB concentration, the relative organ weight, tissue iron contents and blood biochemical indices of piglets. Keywords: Piglets, Ferrous glycine chelate, Ferrous sulfate monohydrate, Relative organ weight, Tissue iron contents, Blood biochemical indice

Conventional solid fermentation alters mycotoxin contents and microbial diversity analyzed by high-throughput sequencing of a Fusarium mycotoxin-contaminated diet

Fusarium mycotoxins, commonly present in corn and its derived products for animals, has caused significant economic impact on swine reproduction in China. The objective of the present study therefore was to evaluate changes in mycotoxin contents and microbial diversity by conventional solid fermentation of a contaminated diet. Three diets were evaluated, as follows: control group, basal diet; test group 1 (25Toxin), basal diet in which corn and corn gluten meal were replaced with 25% mycotoxin-contaminated corn and corn gluten meal, respectively; test group 2 (50Toxin), basal diet in which corn and corn gluten meal were replaced with 50% mycotoxin-contaminated corn and corn gluten meal, respectively. Compound strains were used for solid-state fermentation of the compound feed. Under the present experimental conditions, conventional solid fermentation altered microbial diversity, as demonstrated by high-throughput sequencing of a Fusarium mycotoxin-contaminated diet, and the content of ZEA was reduced significantly. However, deleterious effects were also observed with regard to the contents of DON and FUMB1. These results may have implications for animals consuming Fusarium mycotoxin-contaminated food or feed by conventional solid fermentation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Effects of purified zearalenone on selected immunological measurements of blood in post-weaning gilts

Zearalenone (ZEA), an estrogenic mycotoxin, is produced mainly by Fusarium fungi. Previous studies have indicated that acute ZEA exposure induced various damages in different species; however, its transparent hematotoxicity in female piglets at dietary levels of 1.1 to 3.2 mg/kg has not been shown. The present study was conducted to investigate the effects of dietary ZEA (1.1–3.2 mg/kg) on hematology, T lymphocyte subset, immunoglobulin, antibody titer, lymphocyte proliferation rate (LPR), and interleukin-2 (IL-2) in peripheral blood of post-weaning gilts. A total of 20 female piglets (Landrace × Yorkshire × Duroc), weaned at 42 d with an average body weight of 10.36 ± 1.21 kg were used in the study. Female piglets were kept in a temperature controlled room, divided into four treatments, and fed a diet based on corn-soybean meal-fishmeal-whey, with an addition of 0, 1.1, 2.0, or 3.2 mg/kg purified ZEA for 18 d ad libitum. Feed intake and refusal were measured daily and individual pigs were weighed weekly. Blood and serum samples were collected for selected immunological measurements. Female piglets fed different levels of dietary ZEA grew similarly with no difference in feed intake. Hematological values including leukocytes, platelets, lymphocytes, hematocrit, and mean corpuscular hemoglobin (MCH) decreased linearly (P < 0.05) as dietary ZEA increased. Female piglets fed diets containing 2.0 mg/kg ZEA or greater showed significantly decreased CD4+CD8+, CD4+, and CD4+/CD8+ in comparison to the control (P < 0.05), whereas CD8+ was significantly increased (P = 0.026) in the gilts which were fed the diet containing 3.2 mg/kg ZEA. Serum immunoglobulin G (IgG) and the antibody titer on d 18 were reduced linearly as dietary ZEA levels increased (P < 0.001). Linear decrease in LPR was observed (P < 0.05). Female piglets fed diets containing 2.0 mg/kg ZEA or more showed significantly decreased IL-2 in comparison to the control (P < 0.05). The results suggested that dietary ZEA at the levels of 1.1 to 3.2 mg/kg can induce different degrees of hematotoxicity and negatively affect immune function in female piglets

The Effects of Partially or Completely Substituted Dietary Zinc Sulfate by Lower Levels of Zinc Methionine on Growth Performance, Apparent Total Tract Digestibility, Immune Function, and Visceral Indices in Weaned Piglets

The study aimed to evaluate the effects of replacing zinc sulfate (ZnSO4) with a lower level of zinc methionine (ZnMet) on the growth performance, apparent total tract digestibility (ATTD) of nutrients, serum metabolites and immune functions of weaned piglets. Thirty-five weaned Duroc &#215; Landrace &#215; Large White male piglets (10.69 &#177; 0.26 kg) were randomly allotted to five diets. The control diet was supplemented with 100 mg/kg of Zn from ZnSO4, and experimental diets included 75 + 12.5, 50 + 25, 25 + 37.5, and 0 + 50 mg/kg of Zn from ZnSO4 and ZnMet, respectively. The results showed that no differences were observed in growth performance, ATTD of nutrients and serum metabolites among treatments, while serum white blood cell count, lymphocyte count, IgM contents and spleen index were higher (p &lt; 0.01) in piglets fed with 50 + 25 mg/kg of Zn. Zinc digestibility (p &lt; 0.05), IgA content (p &lt; 0.001) and thymus index (p &lt; 0.05) were increased when at least 50% of ZnSO4 was replaced by ZnMet. All the results indicated that using a lower level of ZnMet in weaned piglet&#8217;s diet instead of ZnSO4 had no adverse impacts on ATTD of nutrients and serum metabolites; and a 50 + 25 mg/kg of Zn (from ZnSO4 and ZnMet, respectively) diet showed the best advantages for parameters relating to immune functions

Effects of purified zearalenone on selected immunological and histopathologic measurements of spleen in post-weanling gilts

The present study was aimed at investigating the adverse effects of dietary zearalenone (ZEA) on the lymphocyte proliferation rate (LPR), interleukin-2 (IL-2), mRNA expressions of pro-inflammatory cytokines, and histopathologic changes of spleen in post-weanling gilts. A total of 20 crossbred piglets (Yorkshire × Landrace × Duroc) with an initial BW of 10.36 ± 1.21 kg (21 d of age) were used in the study. Piglets were fed a basal diet with an addition of 0, 1.1, 2.0, or 3.2 mg/kg purified ZEA for 18 d ad libitum. The results showed that LPR and IL-2 production of spleen decreased linearly (P < 0.05) as dietary ZEA increased. Splenic mRNA expressions of interleukin-1β (IL-1β) and interleukin-6 (IL-6) were linearly up-regulated (P < 0.05) as dietary ZEA increased. On the contrary, linear down-regulation (P < 0.05) of mRNA expression of interferon-γ (IFN-γ) was observed as dietary ZEA increased. Swelling splenocyte in 1.1 mg/kg ZEA treatments, atrophy of white pulp and swelling of red pulp in 2.0 and 3.2 mg/kg ZEA treatments were observed. The cytoplasmic edema in 1.1 mg/kg ZEA treatments, significant chromatin deformation in 2.0 mg/kg ZEA treatment and phagocytosis in 3.2 mg/kg ZEA treatment were observed. Results suggested that dietary ZEA at 1.1 to 3.2 mg/kg can induce splenic damages and negatively affect immune function of spleen in post-weanling gilts