Search results for: Oscar fish (Astronotus ocellatus)

Authors: Jaime Muñoz, José Arcos, Oscar Bautista Federico Méndez

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The influence of a pulsatile electroosmotic flow (PEOF) at the rate of spread, or dispersivity, for a non-reactive solute released in a microcapillary with slippage at the boundary wall (modeled by the Navier-slip condition) is theoretically analyzed. Based on the flow velocity field developed under such conditions, the present study implements an analytical scheme of scaling known as the Theory of Homogenization, in order to obtain a mathematical expression for the dispersivity, valid at a large time scale where the initial transients have vanished and the solute spreads under the Taylor dispersion influence. Our results show the dispersivity is a function of a slip coefficient, the amplitude of the imposed electric field, the Debye length and the angular Reynolds number, highlighting the importance of the latter as an enhancement/detrimental factor on the dispersivity, which allows to promote the PEOF as a strong candidate for chemical species separation at lab-on-a-chip devices.

Keywords: dispersivity, microcapillary, Navier-slip condition, pulsatile electroosmotic flow, Taylor dispersion, Theory of Homogenization

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Authors: Hongbo Zhang, Xinlu Tang, Jiangwei Li, Chi Yan

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Home zone parking pilot (HPP) is a fast-growing segment in low-speed autonomous driving applications. It requires the car automatically cruise around a parking lot and park itself in a range of up to 100 meters inside a recurrent home/office parking lot, which requires precise parking lot mapping and localization solution. Although Lidar is ideal for SLAM, the car OEMs favor a low-cost fish-eye camera based visual SLAM approach. Recent approaches have employed segmentation models to extract semantic features and improve mapping accuracy, but these AI models are memory unfriendly and computationally expensive, making deploying on embedded ADAS systems difficult. To address this issue, we proposed a new method that utilizes object detection models to extract robust and accurate parking lot features. The proposed method could reduce computational costs while maintaining high accuracy. Once combined with vehicles’ wheel-pulse information, the system could construct maps and locate the vehicle in real-time. This article will discuss in detail (1) the fish-eye based Around View Monitoring (AVM) with transparent chassis images as the inputs, (2) an Object Detection (OD) based feature point extraction algorithm to generate point cloud, (3) a low computational parking lot mapping algorithm and (4) the real-time localization algorithm. At last, we will demonstrate the experiment results with an embedded ADAS system installed on a real car in the underground parking lot.

Keywords: ADAS, home zone parking pilot, object detection, visual SLAM

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Authors: Sabuj Kanti Mazumder, Mazlan Abd Ghaffar, Simon Kumar Das

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In this study, we analyzed the effects of water temperature and diet on the growth properties and gastric emptying period of juvenile Malabar blood snapper (Lutjanus malabaricus) over a 30day experimental period. Fish were collected from a local hatchery of Pulau Ketam, Selangor, Malaysia and immediately transferred to flow-through sea water system and subjected to four different temperatures (22, 26, 30, and 34 °C) and two diets (formulated pellet and shrimp). Body weight gain, food consumption, food conversion ratio, food consumption efficiency, specific growth rate, relative growth rate, daily growth rate, and gastric emptying period were significantly influenced by temperature and diet (P<0.05). The best food conversion ratio was with the shrimp group recorded at 30°C (1.33±0.08). The highest growth rate was observed in the shrimp group at 30°C (3.97±0.57% day-1), and the lowest was observed in the formulated pellet group at 22°C (1.63±0.29% day-1). No significant difference was observed between the groups subjected to temperatures of 26 and 30°C. Similarly, the lowest gastric emptying period was detected in the shrimp group at 30°C (16h), where the proportion of meal residues in the stomach decreased from 100% to less than 8% after 12h of starvation. A significantly longer gastric emptying period was observed in the formulated pellet group at 22°C (28h). Overall, the best results were observed on shrimp group subjected to a 30°C temperature. The data obtained from this study suggest that a shrimp diet fed on L. malabaricus at 30°C will optimize the commercial production of this commercially important fish species.

Keywords: aquaculture, diet, digestion rate, growth, Malabar blood snapper

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Authors: Oscar Corredor, Alexander Guzman, Adan Leon

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Density is a bulk physical property that indicates the quality of a petroleum fraction. It is also a useful property to estimate various physicochemical properties of fraction and petroleum fluids; however, the determination of density of extra heavy residual (EHR) fractions by standard methodologies, (ASTM D70) shows limitations for samples with higher densities than 1.0879 g/cm3. For this reason, a dilution methodology was developed in order to determinate density for those particular fractions, 87 (EHR) fractions were obtained as products of the fractionation of Colombian typical Vacuum Distillation Residual Fractions using molecular distillation (MD) and extraction with Solvent N-hexane in Supercritical Conditions (SFEF) pilot plants. The proposed methodology showed reliable results that can be demonstrated with the standard deviation of repeatability and reproducibility values of 0.0031 and 0.0061 g/ml respectively. In the same way, it was possible to determine densities in fractions EHR up to 1.1647g/cm3 and °API values obtained were ten times less than the water reference value.

Keywords: API, density, vacuum residual, molecular distillation, supercritical fluid extraction

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Authors: Mahsa Jalili, Essa Ehsan Khan, Signe Dille Lovmo, Augustine Akruwe, Egil Lien, Rolf Erik Olsen, Trygve Sigholt, Atle Magnus Bones

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Data from the Norwegian Directorate of Fisheries reported that >1.2 million tons of Atlantic salmon were produced in Norway aquaculture industry in 2016. Peroxisome proliferator-activated receptors (PPARs) are one of the key transcription factor families that respond to nutritional ligands. Recent studies have shown the connection between PPARs with lipid and carbohydrate metabolism in aquaculture. To our knowledge, there is no published data about the effects of krill meal, soybean meal, Bactocell ® and butyrate feedings compared to control group on PPARs gene and protein expressions in Atlantic salmon. Fish, 1year +postsmolt, average weight 250 gram were cultured for 12 weeks after acclimatization by control commercial feeding in 2 weeks after hatchery. Water oxygen rate, salinity, and temperature were monitored every second day. At the end of the trial, fish were taken from tanks randomly, and four replicates per group were collected and stored in -80 freezers until analysis. Total RNA extracted from posterior part of dorsal fin muscle tissues and Nanodrop and Bioanalyzer was used to check the quality of RNA. Gene expression of PPAR α, β and γ were determined by RT-PCR. The expression of genes of interest was measured relative to control group after normalization to three reference genes. Total protein concentration was calculated by Bradford method, and protein expression was determined with primary PPARγ antibody by western blot. All data were analyzed by ANOVA followed by Benjamini-Hochberg and Bonferroni tests. Probability values <0.05 considered significant. Bactocell® and butyrate groups showed significantly lower PPARα expression. PPARβ and γ were not significantly different among groups. PPARγ mRNA expression was approximately consistent with protein expression pattern, except than butyrate group showed lower mRNA level. The order of PPARγ expression was Bactocell® > soy meal > butyrate > krill meal > control respectively. PPARβ gene expression decreased more in soy meal > butyrate > krill meal > Bactocell® > control groups respectively. In conclusion, the increased expression of PPARγ and α is proposed to represent a reduction tendency of lipid storage in fish fed by Bactocell®, butyrate, soy and krill meal.

Keywords: aquaculture, blotting western, gene expression, krill protein extract, prebiotics, probiotics, Salmo salar

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Authors: Sopana Wongtawee

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Purpose: Adequate bowel cleansing is essential for a high quality, effective and safe colonoscopy. The aims of this study were to compare the efficacy of bowel preparation based on a low-residue diet before 8:00 followed by a clear-liquid diet, and a low-residue diet until 16:00 one day before colonoscopy using sodium phosphate solution (Xubil ®), the side effects of the two protocols and the patient satisfaction with them. Method: This was an endoscopist-blinded, prospective, randomized, controlled trial. A total of 224 patients (112 in each group) scheduled for outpatient colonoscopy met the criteria.They were randomized to either a low-residue diet consisting of white rice porridge with either fish, chicken or eggs before 8:00 followed by a clear-liquid diet (Group 1) or a low-residue diet consisting of the same food and drink, until 16:00 the day before colonoscopy(Group 2). All of them received 45 ml of sodium phosphate solution (Xubil ®) and three glasses of water (300 ml/glass) the evening before and the morning of the procedure. The cleansing efficacy of bowel preparation was rated according to the modified Rajawithi hospital bowel preparation score scale, patient satisfaction with bowel preparation was rated using Likert scale, and side effects of the 2 protocols was assessed using a patient questionnaire. Results: The cleansing efficacy between the two groups was significantly different (p=0.02). Satisfaction with bowel preparation and side effects were not different, except for the feeling of hunger in the first group (p=0.001). Conclusion: The low-residue diet consisting of white rice porridge with fish, chicken or eggs until 16:00 one day before colonoscopy achieved a better bowel-cleansing efficacy than the protocol consisting of clear liquid all day and rice porridge only before 8:00 one day before colonoscopy.

Keywords: bowel preparation, colonoscopy, sodium phosphate solution, nursing management

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Authors: Rajrupa Ghosh, Abhijit Mitra

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Future use of animal protein sources in prawn feeds is expected to be considerably reduced as a consequence of increasing economical, environmental and safety issues. Of main concern has been the use of expensive marine protein sources, such as fish meal which often results in fouling of water quality and disease outbreak in cultured species. To determine prawn capacity to use practical feeds with plant proteins as replacement ingredients to animal protein sources, 8-months growth trial was conducted in two sets of ponds using juvenile (0.02 gm) Macrobrachium rosenbergii. Among the two sets, one set (comprising of three ponds) is experimental pond included formulated feed prepared with 30% Porteresia coarctata dust along with other general ingredients and another set (comprising of another three ponds) is control pond with commercial feed. Mean final weight, percent weight gain, final net yield, feed conversion ratio and survival were evaluated. Higher condition index values, survival rate and gain in prawn weight were observed in experimental pond compared to control pond. Low FCR values were observed in the experimental pond than the control pond. Evaluation of production parameters at the end of the study demonstrated significant differences (P ≥ 0.05) among two ponds. The variation may be attributed to specially formulated plant based feed that not only boosted up the growth of prawns, but also upgraded the ambient aquatic health. These results indicate that fish meal can be replaced with algal protein sources in diets without affecting prawn growth and production.

Keywords: macrobrachium rosenbergii, porteresia coarctata, Indian sundarbans, feed

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Authors: Chamilani Nikapitiya, Mahanama De Zoysa, Jehee Lee

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Most of the bacterial diseases are associated with high mortalities in aquaculture species and causing huge economic losses. Different approaches have been taken to prevent or control of bacterial diseases including use of vaccines, probiotics, chemotherapy, water quality management, etc. Antibiotics are widely applying as chemotherapy to control bacterial diseases, however, it has been shown that frequent use of antibiotics is favored to develop multi-drug resistance bacteria. Therefore, phages and phage encoded lytic proteins are known to be one of the most promising alternatives for antibiotics to avoid the emergence of antibiotic-resistant bacteria. We isolated and characterized the two lytic phages, namely pAh-1 and pAs-1 against pathogenic Aeromonas hydrophila and Aeromonas salmonicida, respectively. Morphological characteristics were analyzed by Transmission electron microscopy (TEM) and host strain specificities were tested with Aeromonas and other closely related bacterial strains. TEM analysis revealed that both pAh-1 and pAsm-1 are composed of an icosahedral head and a segmented tail, and we suggest that, they are new members of Myoviridae family. Genome sizes of isolated phages were estimated by restriction enzyme digestion of genomic DNA using selected endonucleases followed by agarose gel electrophoresis. Estimated genome size of pAh-1 and pAs-1 were approximately 64 Kbp and 120 Kbp, respectively. Both pAh-1 and pAs-1 have shown narrow host specificity. Moreover, protective effects of phage therapy against fish pathogenic A. hydrophila were investigated in zebrafish model. The survival rate was 40% higher when zebrafish received intra-peritoneal injection (i.p.) of pAh-1 were simultaneously challenge A. hydrophila (2 x 106 CFU/fish) compared to that without phage treatment. Overall results suggest that both pAh-1 and pAs-1 can be used as a potential phage therapy to control Aeromonas infections in aquaculture.

Keywords: Aeromonas infections, antibiotic resistance, bacteriophage, bio-control, lytic phage

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Authors: Aditi Chitharanjan Parmar, Marco Gottardo, Giulia Adele Tuci, Francesco Valentino

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The generation of urban organic waste is a significant environmental problem due to the potential release of leachate and/or methane into the environment. This contributes to climate change, discharging a valuable resource that could be used in various ways. This research addresses this issue by proposing a two-step approach by linking biowaste management to aquaculture industry via single cell proteins (SCP) production. A mixture of food waste and municipal sewage sludge (FW-MSS) was firstly subjected to a mesophilic (37°C) anaerobic fermentation to produce a liquid stream rich in short-chain fatty acids (SCFAs), which are important building blocks for the following microbial biomass growth. In the frame of stable fermentation activity (after 1 week of operation), the average value of SCFAs was 21.3  0.4 g COD/L, with a CODSCFA/CODSOL ratio of 0.77 COD/COD. This indicated the successful strategy to accumulate SCFAs from the biowaste mixture by applying short hydraulic retention time (HRT; 4 days) and medium organic loading rate (OLR; 7 – 12 g VS/L d) in the lab-scale (V = 4 L) continuous stirred tank reactor (CSTR). The SCFA-rich effluent was then utilized as feedstock for the growth of a mixed microbial consortium able to store polyhydroxyalkanoates (PHA), a class of biopolymers completely biodegradable in nature and produced as intracellular carbon/energy source. Given the demonstrated properties of the intracellular PHA as antimicrobial and immunomodulatory effect on various fish species, the PHA-producing culture was intended to be utilized as SCP in aquaculture. The growth of PHA-storing biomass was obtained in a 2-L sequencing batch reactor (SBR), fully aerobic and set at 25°C; to stimulate a certain storage response (PHA production) in the cells, the feast-famine conditions were adopted, consisting in an alternation of cycles during which the biomass was exposed to an initial abundance of substrate (feast phase) followed by a starvation period (famine phase). To avoid the proliferation of other bacteria not able to store PHA, the SBR was maintained at low HRT (2 days). Along the stable growth of the mixed microbial consortium (the growth yield was estimated to be 0.47 COD/COD), the feast-famine strategy enhanced the PHA production capacity, leading to a final PHA content in the biomass equal to 16.5 wt%, which is suitable for the use as SCP. In fact, by incorporating the waste-derived PHA-rich biomass into fish feed at 20 wt%, the final feed could contain a PHA content around 3.0 wt%, within the recommended range (0.2–5.0 wt%) for promoting fish health. Proximate analysis of the PHA-rich biomass revealed a good crude proteins level (around 51 wt%) and the presence of all the essential amino acids (EAA), together accounting for 31% of the SCP total amino acid composition. This suggested that the waste-derived SCP was a source of good quality proteins with a good nutritional value. This approach offers a sustainable solution for urban waste management, potentially establishing a sustainable waste-to-value conversion route by connecting waste management to the growing aquaculture and fish feed production sectors.

Keywords: feed supplement, nutritional value, polyhydroxyalkanoates (PHA), single cell protein (SCP), urban organic waste.

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Authors: Oscar Javier Herrera, Manuel Angel Camacho

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This paper addresses a cutting edge method of business demand forecasting, based on an empirical probability function when the historical behavior of the data is random. Additionally, it presents error determination based on the numerical method technique ‘propagation of errors’. The methodology was conducted characterization and process diagnostics demand planning as part of the production management, then new ways to predict its value through techniques of probability and to calculate their mistake investigated, it was tools used numerical methods. All this based on the behavior of the data. This analysis was determined considering the specific business circumstances of a company in the sector of communications, located in the city of Bogota, Colombia. In conclusion, using this application it was possible to obtain the adequate stock of the products required by the company to provide its services, helping the company reduce its service time, increase the client satisfaction rate, reduce stock which has not been in rotation for a long time, code its inventory, and plan reorder points for the replenishment of stock.

Keywords: demand forecasting, empirical distribution, propagation of error, Bogota

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Authors: Obasi Igwe Oscar, Udokure Ubong James, Echebiri Raphael Ndubuisi

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The study examined the determinants of the welfare of itinerant palm oil marketers in Akwa Ibom State, Nigeria. Multistage sampling techniques were adopted to select 120 itinerant palm oil marketers for the study. Primary data were obtained using a structured questionnaire. Data were analyzed using the cost and returns formula and multiple regression model. Results showed that itinerant palm oil marketing was profitable and 57.39% efficient. The respondents' monthly expenditure of N111,787.90 on food and non-food items indicated that they live above the extreme poverty threshold of $2.15 per person per day, with a daily spending of over $2. Net income (P<0.05), age (P<0.01), educational level (P<0.01), household size (P<0.01), credit amount (P<0.01), market information (P<0.05), amount of tax paid (P<0.01) and the level of market participation (P<0.05) were the significant determinants of the welfare of itinerant traders in the study area. The study recommended that government and non-governmental organizations should make available marketing facilities and enhance transportation networks to reduce inefficiencies and lower transaction costs for itinerant palm oil traders in Akwa Ibom state.

Keywords: determinants, welfare, itinerant, palm oil, marketers

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Authors: Yaya Gao, Jifeng Liu, Yafeng Liu

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Objectives: This study aimed to improve clinicians' understanding and diagnosis of the Mammary analogue secretory carcinoma of the salivary gland（MASC）. Methods: The clinical features of a MASC patient who was admitted to WestChina Hospital of Sichuan University in July 2020 were reviewed and analyzed. A 49-year-old woman with left upper neck pain for three months was admitted to the hospital. She underwent adenoma resection of the left submandibular gland 14 years ago and mucoepidermoid carcinoma resection surgery five years ago. Three months before admission, the patient developed pain in the left mandibular angle after "fatigue" and gradually developed radiation pain in the left ear, which could be relieved after rest. A mass of 1cm could be touched at the mandibular, with tenderness, poor mobility, and hard texture. No swelling, heat, pain, rupture, or pus was found on the surrounding skin. Color doppler ultrasonography of the salivary gland indicated a weak echo mass of 23*14*17mm in the left parotid gland. Results: Surgical excision was completed. Immunohistochemistry of the tumor samples after operation showed that P63（a few，+）, CK7（+）, S100（+）, DOG1（-）, Ki67（MIB-1）（+，5%），pan-TRK（+）, PAS(+) . ETV-6 gene translocation was detected in FISH in postoperative pathology, which indicated MASC. After this diagnosis, the patient sent the postoperative specimen of the second submandibular tumor to our hospital for consultation. The morphology of the two was similar. FISH detected ETV-6 gene translocation, so the second pathological diagnosis was revised to MASC. Conclusion: MASC of the salivary gland is a rare salivary gland tumor whose diagnosis depends on the result of the ETV6-NTRK3 fusion gene.

Keywords: mammary analogue secretory carcinoma, ETV6-NTRK3, salivary gland, misdiagnosed

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Authors: Remy Mpulumba Badiambile, Paul Musa Obadia, Malick Useni Mutayo, Jeef Numbi Mukanya, Patient Nkulu Banza, Tony Kayembe Kitenge, Erik Smolders, Jean-François Picron, Vincent Haufroid, Célestin Banza Lubaba Nkulu, Benoit Nemery

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Background: In July 2021, the Tshikapa river became heavily polluted by mining wastes from a diamond mine in neighboring Angola, leading to massive killing of fish, as well as disease and even deaths among residents living along the Tshikapa and Kasai rivers, a major contributory of the Congo river. The exact nature of the pollutants was unknown. Methods: In a cross-sectional study conducted in the city of Tshikapa in August 2021, we enrolled by opportunistic sampling 65 residents (11 children < 16y) living alongside the polluted rivers and 65 control residents (5 children) living alongside a non-affected portion of the Kasai river (upstream from the Tshikapa-Kasai confluence). We administered a questionnaire and obtained spot urine samples for measurements of thiocyanate (a metabolite of cyanide) and 26 trace metals (by ICP-MS). Metals (and pH) were also measured in samples of river water. Results: Participants from both groups consumed river water. In the area affected by the pollution, most participants had eaten dead fish. Prevalences of reported health symptoms were higher in the exposed group than among controls: skin rashes (52% vs 0%), diarrhea (40% vs 8%), abdominal pain (8% vs 3%), nausea (3% vs 0%). In polluted water, concentrations [median (range)] were only higher for nickel [(2.2(1.4–3.5)µg/L] and uranium [78(71–91)ng/L] than in non-polluted water [0.8(0.6–1.9)µg/L; 9(7–19)ng/L]. In urine, concentrations [µg/g creatinine, median(IQR)] were significantly higher in the exposed group than in controls for lithium [19.5(12.4–27.3) vs 6.9(5.9–12.1)], thallium [0.41(0.31–0.57) vs 0.19(0.16–0.39)], and uranium [0.026(0.013–0.037)] vs 0.012(0.006–0.024)]. Other elements did not differ between the groups, but levels were higher than reference values for several metals (including manganese, cobalt, nickel, and lead). Urinary thiocyanate concentrations did not differ. Conclusion: This study, after an ecological disaster in the DRC, has documented contamination of river water by nickel and uranium and high urinary levels of some trace metals among affected riverine populations. However, the exact cause of the massive fish kill and disease among residents remains elusive. The capacity to rapidly investigate toxic pollution events must be increased in the area.

Keywords: metal contaminants, river water and human urine, pollution by mining wastes, DR Congo

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Authors: Joyce Cruz Ferraz Dutra, Marcele Fonseca Passos, Rubens Maciel Filho, Douglas Fernandes Barbin, Gustavo Mockaitis

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The search for alternatives to control hunger in the world, generated a major environmental problem. Intensive systems of fish production can cause an imbalance in the aquatic environment, triggering the phenomenon of eutrophication. Currently, there are many forms of growth control aquatic plants, such as mechanical withdrawal, however some difficulties arise for their final destination. The Egeria densa is a species of submerged aquatic macrophyte-rich in cellulose and low concentrations of lignin. By applying the concept of second generation energy, which uses lignocellulose for energy production, the reuse of these aquatic macrophytes (Egeria densa) in the biofuels production can turn an interesting alternative. In order to make lignocellulose sugars available for effective fermentation, it is important to use pre-treatments in order to separate the components and modify the structure of the cellulose and thus facilitate the attack of the microorganisms responsible for the fermentation. Therefore, the objective of this research work was to evaluate the structural and morphological transformations occurring in the biomass of aquatic macrophytes (E.densa) submitted to a thermal pretreatment. The samples were collected in an intensive fish growing farm, in the low São Francisco dam, in the northeastern region of Brazil. After collection, the samples were dried in a 65 0C ventilation oven and milled in a 5mm micron knife mill. A duplicate assay was carried, comparing the in natural biomass with the pretreated biomass with heat (MT). The sample (MT) was submitted to an autoclave with a temperature of 1210C and a pressure of 1.1 atm, for 30 minutes. After this procedure, the biomass was characterized in terms of degree of crystallinity and morphology, using X-ray diffraction (XRD) techniques and scanning electron microscopy (SEM), respectively. The results showed that there was a decrease of 11% in the crystallinity index (% CI) of the pretreated biomass, leading to the structural modification in the cellulose and greater presence of amorphous structures. Increases in porosity and surface roughness of the samples were also observed. These results suggest that biomass may become more accessible to the hydrolytic enzymes of fermenting microorganisms. Therefore, the morphological transformations caused by the thermal pretreatment may be favorable for a subsequent fermentation and, consequently, a higher yield of biofuels. Thus, the use of thermally pretreated aquatic macrophytes (E.densa) can be an environmentally, financially and socially sustainable alternative. In addition, it represents a measure of control for the aquatic environment, which can generate income (biogas production) and maintenance of fish farming activities in local communities.

Keywords: aquatics macrophyte, biofuels, crystallinity, morphology, pretreatment thermal

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Authors: Ivan Zupan, Tomislav Saric, Suzana Tkalcic

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IMUNO-2865® is a commercially available, β–glucan based, natural hemicellulose compound with proven immunostimulative properties in people, domestic and some aquatic animals. During the experimental feeding trial with IMUNO-2865® in juvenile wild-caught chub under laboratory conditions, supplementation resulted in overall higher growth performance for all experimental groups regardless of the concentration of the added compound. The maximum, 5% concentration of the supplement, resulted in highest weight gain and calculated specific growth rate. In sea bream, as economically most important species in the Mediterranean aquaculture, significant increases in numbers of monocytes and heterophils were observed in the group supplemented with 2.5 % of IMUNO-2865® in the feed. An overall increase of erythrocytes was noted by the end of the experiment, although with variable distribution among groups. Blood Ca++ levels, total proteins, and total NH₃ were significantly higher after 60 days of feeding in all treatment groups compared to the control and remained elevated in the treated group following the secession of supplementation. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and serum paraoxonase PON1 (U/L) showed similar trends. All these parameters are playing a significant role in either oxygen supplementation of tissues, or anabolic and catabolic processes that on molecular levels contribute to the overall health and immune-building capacity of cells and tissues. The complete lack of mortality in sea bream and presented increases in cellular, biochemical and oxidative stress parameters in the blood suggest that the IMUNO-2865® represents a safe dietary supplement for in aquaculture, with an overall positive and potentially immunostimulative effect on farmed fish.

Keywords: IMUNO-2865®, β–glucans, Mediterranean aquaculture, fish imunnostimulans

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Authors: Lung-Lung Hu

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Ronald Dworkin offered a legal theory of ‘chain enterprise’ that all the judges in legal history altogether create a ‘law’ aiming a specific purpose. Those judges are like co-writers of a chain-story who not only create freely but also are constrained by the story made by the judges before them. The law created by Chinese traditional judges is another case, they, compared with the judges mentioned by Ronald Dworkin, have relatively narrower space of making a legal sentence according to their own discretions because the statutes in Chinese traditional law at the very beginning have been designed as panel code that leaves small room to judge’s discretion. Furthermore, because law is a representative of the authority of the government, i.e. the emperor, any misjudges and misuses deviated from the law will be considered as a challenge to the supreme power. However, different from judges as the defenders of law, Chinese litigation masters who want to win legal cases have to be offenders challenging the verdict that does not favor his or his client’s interest. Besides, litigation master as an illegal or non-authorized profession does not belong to any legal system, therefore, they are relatively freer to ‘create’ the law. According to Stanley Fish’s articles that question Ronald Dworkin and Owen Fiss’ ideas about law, he construes that, since law is made of language, law is open to interpretations that cannot be constrained by any rules or any particular legal purposes. Stanley Fish’s idea can also be applied on the analysis about the stories of Chinese litigation masters in traditional Chinese literature. These Chinese litigation masters’ legal opinions in the so-called chain enterprise are like an unexpected episode that tries to revise the fixed story told by law. Although they are not welcome to the officials and also to the society, their existence is still a phenomenon representing another version of justice different from the official’s and can be seen as a de-structural power to the government. Hence, in this present paper the language and strategy applied by Chinese litigation masters in Chinese legal stories will be analysed to see how they refute made legal judgments and challenge the official standard of justice.

Keywords: Chinese legal stories, interdisciplinary, litigation master, post-structuralism

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Authors: L. Piñeiro, N. Cobas, L. Gómez-Limia, S. Martínez, I. Franco

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The swordfish (Xiphias gladius) is a large oceanic fish of high commercial value, which is widely distributed in waters of the world’s oceans. They are considered to be an important source of high quality proteins, vitamins and essential fatty acids, although only half of the population follows the recommendation of nutritionists to consume fish at least twice a week. Swordfish is consumed worldwide because of its low fat content and high protein content. It is generally sold as fresh, frozen, and as pieces or slices. The aim of this study was to evaluate the effect of salting and frying on the composition of the water-soluble vitamins (B₂, B₃, B₉ and B₁₂) and fat-soluble vitamins (A, D, and E) of swordfish. Three loins of swordfish from Pacific Ocean were analyzed. All the fishes had a weight between 50 and 70 kg and were transported to the laboratory frozen (-18 ºC). Before the processing, they were defrosted at 4 ºC. Each loin was sliced and salted in brine. After cleaning the slices, they were divided into portions (10×2 cm) and fried in olive oil. The identification and quantification of vitamins were carried out by high-performance liquid chromatography (HPLC), using methanol and 0.010% trifluoroacetic acid as mobile phases at a flow-rate of 0.7 mL min^-1. The UV-Vis detector was used for the detection of the water- and fat-soluble vitamins (A and D), as well as the fluorescence detector for the detection of the vitamin E. During salting, water and fat-soluble vitamin contents remained constant, observing an evident decrease in the values of vitamin B₂. The diffusion of salt into the interior of the pieces and the loss of constitution water that occur during this stage would be related to this significant decrease. In general, after frying water-soluble and fat-soluble vitamins showed a great thermolability with high percentages of retention with values among 50–100%. Vitamin B₃ is the one that exhibited higher percentages of retention with values close to 100%. However, vitamin B₉ presented the highest losses with a percentage of retention of less than 20%.

Keywords: frying, HPLC, salting, swordfish, vitamins

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Authors: W. S. Thulasitha, N. Umasuthan, G. I. Godahewa, Jehee Lee

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In fish, innate immune defense is the first immune response against microbial pathogens which consists of several antimicrobial components. Galectins are one of the carbohydrate binding lectins that have the ability to identify pathogen by recognition of pathogen associated molecular patterns. Galectins play a vital role in the regulation of innate and adaptive immune responses. Rock bream Oplegnathus fasciatus is one of the most important cultured species in Korea and Japan. Considering the losses due to microbial pathogens, present study was carried out to understand the molecular and functional characteristics of a galectin in normal and pathogenic conditions, which could help to establish an understanding about immunological components of rock bream. Complete cDNA of rock bream galectin like protein B (rbGal like B) was identified from the cDNA library, and the in silico analysis was carried out using bioinformatic tools. Genomic structure was derived from the BAC library by sequencing a specific clone and using Spidey. Full length of rbGal like B (contig14775) cDNA containing 517 nucleotides was identified from the cDNA library which comprised of 435 bp in the open reading frame encoding a deduced protein composed of 145 amino acids. The molecular mass of putative protein was predicted as 16.14 kDa with an isoelectric point of 8.55. A characteristic conserved galactose binding domain was located from 12 to 145 amino acids. Genomic structure of rbGal like B consisted of 4 exons and 3 introns. Moreover, pairwise alignment showed that rock bream rbGal like B shares highest similarity (95.9 %) and identity (91 %) with Takifugu rubripes galectin related protein B like and lowest similarity (55.5 %) and identity (32.4 %) with Homo sapiens. Multiple sequence alignment demonstrated that the galectin related protein B was conserved among vertebrates. A phylogenetic analysis revealed that rbGal like B protein clustered together with other fish homologs in fish clade. It showed closer evolutionary link with Takifugu rubripes. Tissue distribution and expression patterns of rbGal like B upon immune challenges were performed using qRT-PCR assays. Among all tested tissues, level of rbGal like B expression was significantly high in gill tissue followed by kidney, intestine, heart and spleen. Upon immune challenges, it showed an up-regulated pattern of expression with Edwardsiella tarda, rock bream irido virus and poly I:C up to 6 h post injection and up to 24 h with LPS. However, In the presence of Streptococcus iniae rbGal like B showed an up and down pattern of expression with the peak at 6 - 12 h. Results from the present study revealed the phylogenetic position and role of rbGal like B in response to microbial infection in rock bream.

Keywords: galectin like protein B, immune response, Oplegnathus fasciatus, molecular characterization

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Authors: Oscar Maina Irungu

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Background: Men who have sex with men (MSM) in Mtwapa Town, Kilifi County are at high risk of HIV infection. Probability sample surveys to determine HIV prevalence among MSM in Mtwapa are needed to inform prevention and care services. Methods: In 2013, a cross-sectional survey was conducted among MSM aged 18-24 years old, using respondent-driven sampling (RDS) in Mtwapa. Consenting MSM were tested for HIV (fingerstick rapid test). Population-based prevalence and 95 % confidence intervals (CI) were estimated using RDS Analysis Tool (RDSAT). Results: Among 274 MSM, the median age was 20 years (IQR: 19-23 years). Fifty percent of MSM reported not selling sex, while 13.2 % reported sex work as their “main occupation”, and another 28.4 % reported selling sex in the past two months (but not as their main occupation).Overall HIV prevalence was 19.2 % (CI: 12.2-23.6%). HIV prevalence was higher among MSM who reported sex work as their main occupation (28.3%,CI: 12.1-42.3%) or selling sex in the past two months (26.6 %, CI: 17.2-35.7 %),than among MSM who did not sell sex (11.6%,CI: 7.0-18.1%). Conclusion: HIV prevalence among MSM were high than among Kilifi’s general population aged 15-64 years (8.8%; 2010 KAIS) and highest in male sex workers. Health programs need to address concerns and modify services to meet needs of diverse subgroups of MSM. We recommend continued, periodic surveillance to monitor HIV prevalence among MSM in Mtwapa, and expansion to other areas in Kenya.

Keywords: power point, Kenya, homosexuality, sex

Procedia PDF Downloads 382

Authors: Michael Ricardo Lang, AdriéLle Costa, Ivana Iesbik, Karine Haag, Leonardo Trindade Buffara, Oscar Reimann Junior, Chelin Auswaldt Steclan

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Stroke affects not only the individual, but has significant impacts on the social and family context. Therefore, it is necessary to know the peculiarities of each region, in order to contribute to regional public health policies effectively. Thus, the present study discusses biomarkers in a post-stroke population, admitted to a stroke unit (U-stroke) of reference in the southern region of Brazil. Biomarkers were analyzed, such as age, length of stay, mortality rate, survival time, risk factors and family history of stroke in patients after ischemic stroke. In this studied population, comparing men and women, it was identified that men were more affected than women, and the average age of women affected was higher, as they also had the highest mortality rate and the shortest hospital stay. The risk factors identified here were according to the global scenario; with SAH being the most frequent and those associated with sedentary lifestyle in women the most frequent (dyspilipidemia, heart disease and obesity). In view of this, the importance of studies that characterize populations regionally is evident, strengthening the strategic planning of policies in favor of health care.

Keywords: biomarkers, sex, stroke, stroke unit, population

Procedia PDF Downloads 266

Authors: Elif Tugce Aksun Tumerkan

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Although seafood is an important part of human diet and categorized highly traded food industry internationally, it is remain overlooked generally in the global food security aspect. Food product authentication is the main interest in the aim of both avoids commercial fraud and to consider the risks that might be harmful to human health safety. In recent years, with increasing consumer demand for regarding food content and it's transparency, there are some instrumental analyses emerging for determining food fraud depend on some analytical methodologies such as proteomic and metabolomics. While, fish and seafood consumed as fresh previously, within advanced technology, processed or packaged seafood consumption have increased. After processing or packaging seafood, morphological identification is impossible when some of the external features have been removed. The main fish and seafood quality-related issues are the authentications of seafood contents such as mislabelling products which may be contaminated and replacement partly or completely, by lower quality or cheaper ones. For all mentioned reasons, truthful consistent and easily applicable analytical methods are needed for assurance the correct labelling and verifying of seafood products. DNA-barcoding methods become popular robust that used in taxonomic research for endangered or cryptic species in recent years; they are used for determining food traceability also. In this review, when comparing the other proteomic and metabolic analysis, DNA-based methods are allowing a chance to identification all type of food even as raw, spiced and processed products. This privilege caused by DNA is a comparatively stable molecule than protein and other molecules. Furthermore showing variations in sequence based on different species and founding in all organisms, make DNA-based analysis more preferable. This review was performed to clarify the main advantages of using DNA-barcoding for determining seafood fraud among other techniques.

Keywords: DNA-barcoding, genetic analysis, food fraud, mislabelling, packaged seafood

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Authors: Edwin O. Clarke, Akintade O. Adeboyejo

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Intensive use of pesticides resulted in dispersal of pollutants throughout the globe. This study was carried out to investigate persistent Organochlorine pesticides (POPs) in water, sediment and fin fishes, Schilbes mystus and Hemichromis fasciatus from two different sampling stations along River Ogun between the month of June 2012 and January 2013. The Organochlorine pesticides analyzed include DDT (pp’1,1,1-trichloro-2,2-bis-(4-chlorophenyl) ethane), DDD, DDE (pp1,1-dichloro-2, 2-bis-(4-chlorophenyl) ethylene, HCH (gamma 1,2,3,4,5,6-hexachlorocylohexane, HCB hexachlorobenzene),Dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a octahydro- 1,4,5,8 dimethanonaphthalene). The analysis was done using Gas Chromatograph with Electron Capture Detector. In water sample, the result showed that PPDDT, Endrin aldehyde, Endrin ketone concentrations were high in both stations. The mean value of Organochlorine analyzed in water range from Beta BHC (0.50±0.10µg/l) to PP DDT (162.86±0.21µg/l) in Kara sample station and Beta BHC (0.20±0.07µg/l) to Endrin Aldehyde (76.47±0.02µg/l) in Odo-Ogun sample station. The levels of POPs obtained in sediments ranged from 0.40±0.23µg/g (Beta BHC) to 259.90 ± 1.00µg/kg (Endosulfan sulfate) in Kara sample station and 0.64±0.00µg/g (Beta BHC) to 379.77 ±0.15 µg/g (Endosulfan sulfate) in Odo-Ogun sample station. The levels of POPs obtained in fin fish samples ranged from 0.29±0.00µg/g (Delta BHC) to 197.87 ± 0.31µg/g (PP DDT) in Kara sample station and in Odo-Ogun sample station the mean value for fish samples range from 0.29 ± 0.00 µg/g (Delta BHC) to 197.87 ± 0.32 µg/g (PP DDT). The study showed that the accumulation of POPs affect the environment and reduce water quality. The results showed that the concentrations were found to exceed the maximum acceptable concentration of 0.10µg/l value set by the European Union for the protection of freshwater aquatic life and this can be hazardous if the trend is not checked.

Keywords: hazardous, persistent, pesticides, biomes

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Authors: Alexander Dao, Oscar Wambuguh

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Irritable Bowel Syndrome (IBS) is a heterogeneous functional bowel disease that is characterized by chronic visceral abdominal pain and abnormal bowel function and habits. Its multifactorial pathophysiology and mechanisms are still largely a mystery to the contemporary biomedical community, although there are many hypotheses to try to explain IBS’s presumed physiological, psychosocial, genetic, and environmental etiologies. IBS’s symptomatic presentation is varied and divided into four major subtypes: IBS-C, IBS-D, IBS-M, and IBS-U. Given its diverse presentation and unclear mechanisms, diagnosis is done through a combination of positive identification utilizing the “Rome IV Irritable Bowel Syndrome Criteria'' (Rome IV) diagnostic criteria while also excluding other potential conditions with similar symptoms. Treatment of IBS is focused on the management of symptoms using an assortment of pharmaceuticals, lifestyle changes, and dietary changes, with future potential in microbial treatment and psychotherapy as other therapy methods. Its chronic, heterogeneous nature and disruptive gastrointestinal (GI) symptoms are negatively impactful on patients’ daily lives, health systems, and society. However, with a better understanding of the gaps in knowledge and technological advances in IBS’s pathophysiology, management, and treatment options, there is optimism for the millions of people worldwide who are suffering from the debilitating effects of IBS.

Keywords: irritable bowel syndrome, lifestyle, diet, functional gastrointestinal disorder

Procedia PDF Downloads 89

Authors: Lauren A. Bailey, Amber R. Childs, Nicola C. James, Murray I. Duncan, Alexander Winkler, Warren M. Potts

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For the persistence of fished populations in the Anthropocene, it is critical to predict how fished populations will respond to the coupled threats of exploitation and climate change for adaptive management. The resilience of fished populations will depend on their capacity for physiological plasticity and acclimatization in response to environmental shifts. However, there is evidence for the selection of physiological traits by capture fisheries. Hence, fish populations may have a limited scope for the rapid expansion of their tolerance ranges or physiological adaptation under fishing pressures. To determine the physiological vulnerability of fished populations in the Anthropocene, the metabolic performance was compared between a fished and spatially protected Chrysoblephus laticeps population in response to thermal variability. Individual aerobic scope phenotypes were quantified using intermittent flow respirometry by comparing changes in energy expenditure of each individual at ecologically relevant temperatures, mimicking variability experienced as a result of upwelling and downwelling events. The proportion of high and low-performance individuals were compared between the fished and spatially protected population. The fished population had limited aerobic scope phenotype diversity and fewer high-performance phenotypes, resulting in a significantly lower aerobic scope curve across low (10 °C) and high (24 °C) thermal treatments. The performance of fished populations may be compromised with predicted future increases in cold upwelling events. This requires the conservation of the physiologically fittest individuals in spatially protected areas, which can recruit into nearby fished areas, as a climate resilience tool.

Keywords: climate change, fish physiology, metabolic shifts, over-fishing, respirometry

Procedia PDF Downloads 128

Authors: Roger G. Pagente Jr.

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This study seeks to investigate the language learning experiences of the thirty-nine AB-English majors who were selected through fish-bowl technique from the 157 students enrolled in the AB-English program. Findings taken from the diary, questionnaire and unstructured interview revealed that motivation, learners’ belief, self-monitoring, language anxiety, activities and strategies were the prevailing factors that influenced the learning of English of the participants.

Keywords: diary, English language learning experiences, self-monitoring, language anxiety

Procedia PDF Downloads 606

Authors: M. B. Mshelia, J. K Balogun, J. Auta, N. O. Bankole

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The current status and abundance of the genus Citharinus was carried out in Jebba Lake, Niger State, Nigeria from January to December, 2011. The aim was to determine the extent of exploitation of the genus Citharinus in Jebba Lake so as to advice the government of Nigeria on how to overcome difficulties in terms of the sustainability of the said fish in the Lake. Descriptive statistics were used to analyze the data obtained. A total of 2,389 of the genus Citharinus were caught during the sampling period. Only two species of the genus Citharinus were caught with 1,220 in number and 430.68kg total weight of Citharinus citharus and 1,169 in number and 418.56kg total weight of Citharinus latus). The current total yield estimated for the genus Citharinus in Jebba Lake in the six (6) sampling sites was calculated and pooled together to be 849.24kg. A day’s catch was calculated to be 35.38kg. The monthly and annual yields of the genus Citharinus were calculated to 1061.55 equivalents to 1 ton and 12 metric tonnes respectively. For the fecundity, June, July and August were discovered as the spawning period for the genus Citharinus and out of total experimental gillnet catch of 2, 389, only 244 (10.21%)of Citharinus citharus and 231 (9.67%) of Citharinus latus were in sexually mature stage. Out of these numbers, 113 (46.31%) were males and 121 (53.69%) were females of Citharinus citharus and 112 (48.48) were males and 119 (51.52) were females of Citharinus latus. The youngest mature males in either of the two had a standard length of 31.5 with a weight of 800.5gWhilethe youngest spawning females were having the standard length of 29.5 cm with a weight of 1,3oo.5g.It was also discovered that females started maturing earlier than the males at the standard length for females and males to be 18.0cm and 19.5cm respectively. Their fecundity ranged from 15,000 to 16, 500 eggs. The sex ratio of 1172 that were males and 1217 that were females was 1 male to 1.0383 females which was equivalent to 1:1 sex ratio of male to female. It was concluded that Jebba Lake had suffered seriously over exploitation of the genus Citharinus and proper management have to be enforced on the lake otherwise the threat of fish being extent may arise.

Keywords: Jebba Lake, Niger State, Nigeria, Citharinus citharus, Citharinus latus, fecundity, sex ratio

Procedia PDF Downloads 261

Authors: Hossein Khara, Mahmoud Sayyadborani, Mohammad Sayyadborani

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In the present study, we examined the effects of different dietary levels of ascorbic acid (vitamin C) and α-tocopherol (vitamin E) and their combinations on growth, survival and some haematological and immunological parameters of Caspian brown trout, Salmo trutta caspius juveniles. 15 experimental treatments and one control group with three replicates were considered for experiment. The experimental treatments were fish fed by experimental diets containing different levels of Vit C and E as follow: T1: Vit E (20 mg.kg diet -1) + Vit C (100 mg.kg diet -1), T2: Vit E (30 mg.kg diet -1) + Vit C (100 mg.kg diet -1), T3: Vit E (40 mg.kg diet -1) + Vit C (100 mg.kg diet -1), T4: Vit E (20 mg.kg diet -1) + Vit C (200 mg.kg diet -1), T5: Vit E (30 mg.kg diet -1) + Vit C (200 mg.kg diet -1), T6: Vit E (40 mg.kg diet -1) + Vit C (200 mg.kg diet -1), T7: Vit E (20 mg.kg diet -1) + Vit C (300 mg.kg diet -1), T8: Vit E (30 mg.kg diet -1) + Vit C (300 mg.kg diet -1), T9: Vit E (40 mg.kg diet -1) + Vit C (300 mg.kg diet -1), T10: Vit C (100 mg.kg diet -1), T11: Vit C (200 mg.kg diet -1), T12: Vit C (300 mg.kg diet -1), T13: Vit E (20 mg.kg diet -1), T14: Vit E (30 mg.kg diet -1) T15: Vit E (40 mg.kg diet -1). Also a non-vitamin supplemented was considered as control group. Growth parameters were measured monthly and serum parameters assayed at the end of the experiment. According to our results, Vit C and E improved survival and growth parameters including specific growth rate (SGR), weight gain percent (WG%) and biomass. The highest values of these parameters obtained in T8, T9 and T8 respectively. The lowest FCR obtained in T8. The haematological parameters including red blood cells (RBCs), white blood cells (WBCs), haematocrit (Hct) and haemoglobin (Hb) were higher in vitamin treated groups than control group with highest values in T8. In T13, WBC values were higher compared to other experimental groups. The immunological parameters including lysozyme activity, Immunoglobulin (IgM) and total immunoglobulin (TIg) were significantly higher in vitamin supplemented groups than in control group. In this regard the highest values of these parameters were found in T12. The lowest values of TIg and lysozyme activity were observed in control group and fish fed by only vitamin E i.e. T13, T14 and T15. In conclusion, our results show that Vit C and E in combination or only can improve growth, survival, haematological and immunological indices of Caspian brown trout.

Keywords: vitamins E, vitamins C, growth, survival, haematological parameters, immunological parameters

Procedia PDF Downloads 343

Authors: Sali Chinsathit, Haruthai Kaenla

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Organic agriculture has become a major policy theme for agricultural development in Thailand since October 2005. Organic farming is enlisted as an important national agenda, to promote safe food and national export, and many government authorities have initiated projects and activities centered on organic farming promotion. Currently, Thailand has the market share of about 32 million US$ a year by exporting organic products of rice, vegetables, tea, fruits and a few medicinal herbs. There is high potential in organic crop production as there is the tropical environment promoting crop growth and leader farmer in organic farming. However, organic sector is relatively small (0.2%) comparing with conventional agricultural area, since there are many factors affecting farmers’ adoption and success in organic farming. The objective of this project was to get the organic production technology for at least 3 organic crops. The treatment and method were complied with Thai Organic Standard, and were mainly concerned on increase plant biodiversity and soil improvement by using organic fertilizer and bio-extract from fish, egg, plant and fruits. The bio-logical control, plant-extracts, and cultural practices were used to control insect pests and diseases of 3 crops including mangosteen (Garcinia mangostana L.), longkong (Aglaia dookoo Griff.) and banana (Musa (AA group)). The experiments were carried out at research centers of Department of Agriculture and farmers’ farms in Rayong and Chanthaburi provinces from 2009 to 2013. We found that both locations, plant biodiversity by intercropping mangosteen or longkong with banana and soil improvement with composts and bio-extract from fish could increased yield and farmers’ income by 6,835 US$/ha/year. Farmers got knowledge from these technologies to produce organic crops. The organic products were sold both in domestic and international countries. The organic production technologies were also environmental friendly and could be used as an alternative way for farmers in Thailand.

Keywords: banana, longkong, mangosteen, organic farming

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Authors: Héctor Rivera-Gómez, Eva Selene Hernández-Gress, Oscar Montaño-Arango, Jose Ramon Corona-Armenta

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This research studies the joint production, maintenance and subcontracting control policy for an unreliable deteriorating manufacturing system. Production activities are controlled by a derivation of the Hedging Point Policy, and given that the system is subject to deterioration, it reduces progressively its capacity to satisfy product demand. Multiple deterioration effects are considered, reflected mainly in the quality of the parts produced and the reliability of the machine. Subcontracting is available as support to satisfy product demand; also overhaul maintenance can be conducted to reduce the effects of deterioration. The main objective of the research is to determine simultaneously the production, maintenance and subcontracting rate which minimize the total incurred cost. A stochastic dynamic programming model is developed and solved through a simulation-based approach composed of statistical analysis and optimization with the response surface methodology. The obtained results highlight the strong interactions between production, deterioration and quality which justify the development of an integrated model. A numerical example and a sensitivity analysis are presented to validate our results.

Keywords: subcontracting, optimal control, deterioration, simulation, production planning

Procedia PDF Downloads 579

Authors: Pinna Beatrice., Laini Alex, Negro Giovanni, Burgazzi Gemma, Viaroli Pierluigi, Vezza Paolo

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Habitat models rarely consider macroinvertebrates as ecological targets in rivers. Available approaches mainly focus on single macroinvertebrate species, not addressing the ecological needs and functionality of the entire community. This research aimed to provide an approach to model the habitat of the macroinvertebrate community. The approach is based on the recently developed Flow-T index, together with a Random Forest (RF) regression, which is employed to apply the Flow-T index at the meso-habitat scale. Using different datasets gathered from both field data collection and 2D hydrodynamic simulations, the model has been calibrated in the Trebbia river (2019 campaign), and then validated in the Trebbia, Taro, and Enza rivers (2020 campaign). The three rivers are characterized by a braiding morphology, gravel riverbeds, and summer low flows. The RF model selected 12 mesohabitat descriptors as important for the macroinvertebrate community. These descriptors belong to different frequency classes of water depth, flow velocity, substrate grain size, and connectivity to the main river channel. The cross-validation R² coefficient (R²𝒸ᵥ) of the training dataset is 0.71 for the Trebbia River (2019), whereas the R² coefficient for the validation datasets (Trebbia, Taro, and Enza Rivers 2020) is 0.63. The agreement between the simulated results and the experimental data shows sufficient accuracy and reliability. The outcomes of the study reveal that the model can identify the ecological response of the macroinvertebrate community to possible flow regime alterations and to possible river morphological modifications. Lastly, the proposed approach allows extending the MesoHABSIM methodology, widely used for the fish habitat assessment, to a different ecological target community. Further applications of the approach can be related to flow design in both perennial and non-perennial rivers, including river reaches in which fish fauna is absent.

Keywords: ecological flows, macroinvertebrate community, mesohabitat, river habitat modeling

Procedia PDF Downloads 94