12 research outputs found
Application of multiple regression analysis to morphometric characters obtained from Serranus cabrilla (Linnaeus, 1758) by using stepwise method
In fisheries science, high number of morphometric measures (independent variables) taken from different parts of the fish complicates the estimation of the body weight (dependent variable). Therefore, the researchers are seeking for a solution facilitating the interpretation of the equations of correlation between the characteristics. One way to deal with this challenge is the dimension reduction by means of stepwise multiple regression analysis. The aim of this study is to explain total variation with the same accuracy by using fewer independent variables. To accomplish this, 12 morphometric measures from 210 individuals of Serranus cabrilla were measured to estimate the body weight. Firstly, the 95% of the variation was explained by means of multiple regression analysis by using all variables. Then, by step-wise method, the same results were achieved with fewer independent variables. Finally, the variables with inter-multicollinearity eliminated and with two remaining independent variables determination coefficients resulted as 95%. The result showed that using more variables does not create significant distinction for accuracy to estimate the body weight although; the total length and body dept was the most effective features for weight. © 2018, Agricultural Research Communication Centre. All rights reserved
Olive oil consumption attitudes as a healthy food: A survey study on young consumers
This aim of the study is to examine consumption patterns and purchase behaviour of young consumers (15-27 years old) for olive oil which is a healthy, natural and traditional food. A face to face consumer survey was used to gather information. The results show that, age differences affect consumption behaviour. The primary factor affecting the consumption of olive oil among the young consumers is health and this factor is followed by taste. Young consumers are extremely sensitive on price in terms of their purchase decisions and they highly prefer extra virgin olive oil and shows low interest on gourmet olive oils. In terms of quality perception, it has been determined that young consumers pay attention to consistency and they do not care on the region and variety of the olive. In addition, it has been determined that young consumers are willing to pay more for organic and traditionally processed olive oils
Economic efficiency performance of small-scale fisheries in the east mediterranean coast of Turkey
In this study, it is aimed to analysis of the economic efficiency of the small-scale coastal fishing activities operating on the Eastern Mediterranean coast of Turkey. In this context, face-to-face surveys were conducted with small-scale fishermen during the 2016-2017 fishing season and so these fisherman’s input usage, total revenue structures and socio-economic and demographic characteristics were determined. Data Envelopment Analysis method was applied to determine the economic efficiency levels of small-scale fisheries and extreme levels of input use was demonstrated. In addition, a Tobit Regression Model was applied to detect the factors causing the inefficiency of these small-scale fishers. The results of the analysis reveal that the average economic efficiency levels of the small-scale fishermen operating in the research area under the variable return to scale are 0.64. According to the results, it is possible to realize the same output performance when the fishers’ use of inputs is reduced by 36.1%. The main inputs leading to inefficiency in the output performance of small-scale fishers are determined as vessel maintenance expenditures (15.4%), fishing gear repair or purchase expenditures (12.3%) and labour costs (12%). In addition, Tobit Analysis was applied to investigate the relationship between the economic efficiency results and the socio-economic and demographic situation of small-scale fishermen. According to this, household size, working hours and vessel ownership factors causes economic inefficiency on the focused fishermen. © 2018, Bononia University Press. All rights reserved
Comparison of the proximate compositions and fatty acid profiles of gilthead sea bream (Sparus aurata) and sole (Solea solea)
Seasonal changes in the proximate composition and fatty acids of gilthead sea bream (S. aurata) and sole (S. solea) were investigated. The fish species (S. aurata and S. solea) analyzed were fairly high in protein (20.41-22.63 %). The highest lipid levels of gilthead sea bream were found in September and December. However the lipid levels of sole displayed fluctuations according to months with the highest values in September. The percentages of EPA and DHA of gilthead sea bream were between 3.86-4.59 and 5.96-19.64 %, respectively, according to the months. However, The EPA and DHA of the sole were also found 2.17-2.94 and 6.33-10.99 %, respectively. The ratios of n-3/n-6 PUFA content indicating the availability of n-3 PUFA that are beneficial for human health were 8.06, 18.97, 6.45 for gilthead sea bream and 5.53, 6.46, 6.65 for sole in December, April, September, respectively. The results of this study show that the consumption of gilthead sea bream and sole could meet this demand in terms of n-3 PUFA contents and the effects on health
Growth and mortality of the brushtooth lizardfish (Saurida undosquamis) in Iskenderun Bay (eastern Mediterranean Sea) using length frequency analysis
The growth and mortality of brushtooth lizardfish Saurida undosquamis (Richardson, 1848) in Iskenderun Bay (eastern Mediterranean Sea) were investigated based on length frequency data using the fisat software. Total length of the sampled 4711 fish ranged from 6.0 to 39.0 cm. The von Bertalanffy growth function estimates were L? = 42.00 cm, k = 0.51 year-1, t0 = -0.29 years. Total mortality rate (Z) was computed as 1.76 year-1 and the exploitation ratio was 0.51, indicating that the brushtooth lizardfish stock is on the verge being overfished. © 2007 The Authors
Determination of the relationship among air velocity, cooling efficiency and temperature decrease at a cellulose based evaporative cooling pad
The aim of this study is to determine the relationship between air velocity, cooling efficiency and decrease of the temperature of the air passing the pad, at a cellulose based evaporative cooling pad and to gain handy information for the persons working on this subject. In the study, cellulose based evaporative cooling pad (CELdek R 7060-15) was handled as material. As for the velocity of air passing through the pad 0.5, 1.0 and 2.0 ms-1 values were selected. Based on the measurement results, cooling efficiency and provided decrease of the temperature of the air passing the pad, were calculated. As a result of the research, cooling activities calculated between 3 different air velocities were found significant in the statistical sense (p < 0.01) for the measurement periods except II. measurement periods. As for the temperature decrease, the difference between other measurement periods except II. and III. measurement periods, were also found significant. The highest cooling activity and temperature decreases were reached at 0.5 and 1.0 ms-1 air velocities. It can be said that according to statistical data, optimal air velocity for the Mediterranean climatic conditions should be between 0.5 and 1.0 ms-1, among the selected air velocities. ©2010 Academic Journals
Seasonal variations in proximate and fatty acid compositions of two commercially important fish, hake (Merluccius merluccius) and lizardfish (Saurida undosquamis), from the northeastern Mediterranean Sea
Hake (Merluccius merluccius) and lizardfish (Saurida undosquamis) were caught seasonally at the northeastern Mediterranean Sea to determine their proximate compositions and fatty acid contents. Statistical (P < 0.05) differences among seasons were observed in the values of moisture, protein, lipid and ash. Saturated fatty acids and polyunsaturated fatty acids were the most abundant fatty acids in both species, with palmitic acid (C16:0), eicosapentaenoic acid (C20:5 n-3) and docosahexaenoic acid (C22:6 n-3). This research demonstrated that these species were characterized by low lipid content and were also a good source of unsaturated fatty acids. Therefore, hake and lizardfish, in terms of nutritional quality, could be recommended for human consumption. © 2008, Wiley Periodicals, Inc
Width/length-weight and relationships of the blue crab (Callinectes sapidus Rathbun, 1986) population living in Camlik Lagoon Lake (Yumurtalik)
In this study, the width/length-weight relationships of the blue crab population (Callinectes sapidus Rathbun, 1986) living in Camlik Lagoon Lake (Adana) were investigated considering sex and maturity. A total of 743 samples were collected and analyzed. The Carapace Width (CW) distribution ranged from 2.30 to 17.80 cm and the weight distribution ranged from 0.70 to 301 g. Carapace width/carapace length-weight relationships was found to be as W = 0.4782CL 3.106 (R = 0.987) and W = 0.0902CW2.932 (R = 0.982). © 2006 Asian Network for Scientific Information