93 research outputs found

    Growth and reproduction of (Capoeta damascina Valenciennes 1842) from the Hanna wetland, Semirum

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    As part of ecological study of Hanna Wetland, Semirum, in Isfahan province, the age, growth, and reproductive characteristics of Capoeta damascina, a major species of the wetland were investigated. A total of 270 specimens were collected by cast net and gillnets of different mesh sizes (5-70mm) during fall and winter 2007, and spring and summer 2008. The ratio of males to females was 1.0: 2.2 (MT). Seven (1+ to n and six (1+ to 6+) year classes were recorded for females and males, respectively. In all class, females were always larger than males. Maximum fork length and weight of 44.2 cm and 1545g for females and 40.0cm and 1300g for males were recorded. The minimum, maximum, and average absolute fecundity were 2203, 36763, and 19121±9503, respectively. According to Gonadostomatic Index (GSI) values, spawning of C. damascina occurs from May to June. The Von Bertalanffy growth parameters fit to size-at-age data were: K=0.136, L∞=66.96cm, to .0.161 years for females and K=0.174, 1,0,=54.70cm, t, 0.37 for males. The weigh-length relationships were described as W=0.0143L3a^0.471 (r^2 = 0.9597) for females and W=0.009401695 (r^2 =7- 0.9768) for males. According to b values obtained, both sexes show a positive allometric growth. The growth performance index 9' was estimated at 7.071 and 6.092 for females and males respectively that indicated a faster growth rate for females

    Age and growth of the Mesopotamian barb, Capoeta damascina, in central Iran

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    Age and growth of Mesopotamian barb, Capoeta damascina, were studied in the Zayandehrud River, in central Iran, from March 2007 to April 2008. Among the 689 specimens studied, age groups in males ranged from 1+ to 9+ and that in females ranged from 1+ to 10+. The sex ratio (1 M: 1.6 F) was not significantly different from 1:1 ratio. Maximum fork length and weight was 39 cm and 1.115 g for males and 54.2 cm and 2.340 g for females. In all age classes, females were larger than males. The most frequent age groups were 3+ in males and 4+ in females. The highest value for condition factor was observed in June. The growth of C. damascina was described by von Bertalanffy growth curve as k=0.01, L_∞=56.2 cm, t_0=-0.63 for males and k = 0.05, L_∞=117.1 cm and t_0= -0.43 years for females. The length-weigh relationship was described as W=0.0169L^2.95 (r^2 =0.98) for males and as W=0.0155L2.99 (r^2 =0.99) for females, indicating an isometric growth pattern in both sexes. Growth performance index φ` was estimated as 5.73 for males and 6.53 for females, indicating a faster growth rate in females

    An investigation on fish parasites in Hanna Wetland, Semirom, Isfahan Province

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    As a part of a major ecological study of Hanna Wetland, Semirum Region, Isfahan Province, parasitic infestation of 3 native and one introduced fish species were investigated. A total of 120 fish specimens were collected by both cast net and a series of gillnets between fall and winter 2007, and spring and summer 2008. Some of the observed parasites are reported for the first time as new host records of: Trichodina perforata on gill and skin of Carassius auratus auratus and three species of leeches namely: Glossiphonia heteroclite, Thromyzon tessulatum and Hemiclepsis marginata on the skin and fin bases of Capoeta damascina. Moreover, 14 internal and external parasites including: one protozoan; Ichthyophthirius multifiliis and two myxosporeans; Myxobolus varicorhini, Myxobolus sp., three monogeneans; Dactylogyrus lenkoran, Dactylogyrus intermedius and Gyrodactylus sp., two immature digeneans; Diplostomum spathaceum, Tylodephys sp., two mature digeneans; Allocreadium isoporum and A. layman, one unknown cyst, one Acanthocephalan; Acanthocephalorhynchoides sp., one cestoda; Khawia armeniaca. The highest prevalence of Diplostomum spathaceum (100%) was observed in Aphanius isfahanensis and Alburnus sp. However, the lowest prevalence was related to A. layman in Capoeta damascina in winter (0%), and autumn and spring (11%). Leeches infections were only observed in Capoeta damascina and Alburnus sp. in winter and summer, respectively. The maximum average (±SD) infection intensity belonged to K. armeniaca in intestine of C. damascina in spring (12.50±3.40, range: 8-16). Among the parasites identified in the region, D. spathaceum showed the highest mean (±SD) abundance (41.67±11.79) in C. auratus auratus in spring. In general, a relatively high diversity of fish parasitic fauna exists in this water body which could jeopardize fish populations and the whole ecosystem if the ecological status of the Hanna Wetland is neglected

    Myxobolus spp. (Myxosporea: Myxobolidea) from fishes of the Zayandeh-rud River (Esfahan, Iran); new hosts and locality record

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    In a parasitic survey of the native and introduced fishes in the Zayandeh-rud River, 5 Myxobolus spp. were found in the gills, fins and skin of examined fish specimens. They include M. varicorhini from fin and M. samgoricus from skin of Capoeta damascina, M. musajevi from gills of Capoeta capoeta gracilis, Myxobolus cristatus from Capoeta aculeata, and M. saidovi from Alburnus sp. Data on the location in the hosts comparing with previous records are provided. The epidemiological importance of Myxobolus spp. in Zayandeh-rud River is also presented. In the present paper the occurrence of five Myxobolus spp. all from endemic fishes from Zayandeh-rud River (a new locality) are recorded from two new hosts; Capoeta damascina, Capoeta aculeata. M. varicorhini and M. saidovi are recorded for the first time from Iranian freshwater fishes

    Age, growth and reproduction of Chondrostoma regium (Heckel, 1843) from the Zayandeh Roud River, Iran

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    Age, growth and reproduction were investigated for Chondrostoma regium, collected monthly (November 2007- August 2008) from the Dimeh Spring region, Zayandeh Roud River, Iran. The maximum age of collected female and male fish were estimated based on scale increments as five and four years respectively. Von Bertalanffy growth equations were calculated as Lt=246[1-e^-0.206(t-0.034)], Wt=163.29[1-e^-0.206(t-0.034)]^2.77 for females and Lt=253.1[1-e^-0.206(t-0.175)], Wt=188.25[1-e^-0.206(t-0.175)]^2.99 for males. Size ranges of the male and female specimens were almost similar. The fork length range for females was 10.5-18.0 cm and 10.7-19.7 cm for males; and the weight range was 15.7-85.4 g in females, and 14.5-88.5 g in males. The female-male ratio was 1.8:1 (p<0.05), and for both sexes gonadal development and sexual maturity occurred in the second year of their life. Length-weight relationships revealed isometric growth pattern for males and a negative allometric growth for females. Monthly data of Gonadosomatic Index, and ovary condition suggested that spawning occurred during May and June. The mean absolute and relative fecundity was calculated as 2429±1512 (eggs/female) and 78.1±18.7 (egg/g), respectively, and fecundity was significantly correlated with both body weight (r^2=0.90) and fork length (r^2=0.84)

    Optimizing machine learning for agricultural productivity: A novel approach with RScv and remote sensing data over Europe

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    CONTEXT: Accurate estimating of crop yield is crucial for developing effective global food security strategies which can lead to reduce of hunger and more sustainable development. However, predicting crop yields is a complex task as it requires frequent monitoring of many weather and socio-economic factors over an extended period. Satellite remote sensing products have become a reliable source for climate-based variables. They are easier to obtain and provide detailed spatial and temporal coverage. OBJECTIVE: The aim of this study is to assess the effectiveness of implement a novel optimization algorithm, called Randomized Search cross validation (RScv), on various machine learning algorithms and measure the prediction accuracy enhancement. METHODS: Annual yields of four crops (Barley, Oats, Rye, and Wheat) were predicted across 20 European countries for 20 years (2000–2019). Two NASA missions, namely GPCP and GLDAS satellites, provided us with climate- and soil-based input variables. Those variables were employed as the input of four ensemble Machine Learning (ML) algorithms (Ada-Boost (AB), Gradient Boost (GB), Random Forest (RF) and Extra Tree (ET)) which are faster and more adoptable compare to classic AI algorithms. RESULTS AND CONCLUSIONS: Main results show that applying RScv improves the prediction ability of all ML models over the four crops. In particular, the RScv-AB reaches the overall highest accuracy for predicting yields (R2max = 0.9). Spatial evaluation of predicting errors depicts that the proposed models were more shifted toward underestimation. An uncertainty analysis was also carried out which shows that applying ML algorithms creates higher and lowers uncertainty in Barley and Wheat respectively. SIGNIFICANCE: Considering the robustness of the optimised ML models and the global coverage of remote sensing data, our current methodology demonstrates great transferability and can be applied in other regions across the globe with higher temporal extents. In addition, this tool could be beneficial to decision makers in various sectors to improve the water allocations, deal with climate change effects and keep sustainable agricultural development.Antonio Jodar-Abellan acknowledges financial support received form the Margarita Salas Postdoc Spanish Program

    Genome-wide association study for lignocellulosic compounds and fermentable sugar in rice straw

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    Cellulose and lignin are the two main components of secondary plant cell walls with substantial impact on stalk in the field and on straw during industrial processing. The amount of fermentable sugar that can be accessed is another important parameter affecting various industrial applications. In the present study, genetic variability of rice (Oryza sativa L.) genotypes for cellulose, lignin, and fermentable sugars contents was analyzed in rice straw. A genome-wide association study of 33,484 single nucleotide polymorphisms (SNPs) with a minor allele frequency (MAF) >0.05 was performed. The genome-wide association study identified seven, three, and three genomic regions to be significantly associated with cellulose, lignin, and fermentable sugar contents, respectively. Candidate genes in the associated genomic regions were enzymes mainly involved in cell wall metabolism. Novel SNP markers associated with cellulose were tagged to GH16, peroxidase, GT6, GT8, and CSLD2. For lignin content, Villin protein, OsWAK1/50/52/53, and GH16 were identified. For fermentable sugar content, UTP-glucose-1-phosphate uridylyltransferase, BRASSINOSTEROID INSENSITIVE 1, and receptor-like protein kinase 5 were found. The results of this study should improve our understanding of the genetic basis of the factors that might be involved in biosynthesis, turnover, and modification of major cell wall components and saccharides in rice straw

    Genome-Wide Association Mapping of Mixed Linkage (1,3;1,4)-beta-Glucan and Starch Contents in Rice Whole Grain

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    The glucan content of rice is a key factor defining its nutritional and economic value. Starch and its derivatives have many industrial applications such as in fuel and material production. Non-starch glucans such as (1,3;1,4)-beta-D-glucan (mixed-linkage beta-glucan, MLG) have many benefits in human health, including lowering cholesterol, boosting the immune system, and modulating the gut microbiome. In this study, the genetic variability of MLG and starch contents were analyzed in rice (Oryza sativa L.) whole grain, by performing a new quantitative analysis of the polysaccharide content of rice grains. The 197 rice accessions investigated had an average MLG content of 252 mu g/mg, which was negatively correlated with the grain starch content. A new genome-wide association study revealed seven significant quantitative trait loci (QTLs) associated with the MLG content and two QTLs associated with the starch content in rice whole grain. Novel genes associated with the MLG content were a hexose transporter and anthocyanidin 5,3-O-glucosyltransferase. Also, the novel gene associated with the starch content was a nodulin-like domain. The data pave the way for a better understanding of the genes involved in determining both MLG and starch contents in rice grains and should facilitate future plant breeding programs

    Growth and reproductive characteristics of Squalius Lepidus Heckel 1843 in the Dimeh spring of Zayandeh-Rud River

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    Population structure, growth, and reproductive characteristics of Kavar, Squalius lepidus, a native species of Cyprinidae family in Zayandeh-Rud River were investigated by monthly sampling from October 2006 to August 2007. A total of 415 individuals were collected. Age groups of males and females ranged between 1+ and 4+ . The male:female sex ratio was 1:3. The largest female was 163.0mm in fork length and 63.71g in weight; whereas the largest male was 156.0mm in fork length and 50.45g in weight. The minimum, maximum, and mean absolute fecundity was 1161, 12953, and 4279±2169, respectively, and relative fecundity was 148.4±49.3 eggs/g of body weight. Gonadostomatic Index (GSI) values suggested that spawning of Squalius lepidus occurs from May to June. Thus, Squalius lepidus is considered an intermittent spawner species. Growth parameters for both sexes were stated by the vonBertalanffy growth function as k = 0.162, L = 232mm, to = -0.427 years for females and k = 0.136, L =217mm, to =- 0.847 years for males. The weight-length relationship was described as W = 0.00005L 2.827 (r2= 0.860) for males and W = 0.00005 L2.855 (r2 = 0.859) for females. The slope of the regression line (b) fitted through the weight-length data suggested a negative allometric growth for both females and male (P<0.05)

    A Study of Concurrency Bugs and Advanced Development Support for Actor-based Programs

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    The actor model is an attractive foundation for developing concurrent applications because actors are isolated concurrent entities that communicate through asynchronous messages and do not share state. Thereby, they avoid concurrency bugs such as data races, but are not immune to concurrency bugs in general. This study taxonomizes concurrency bugs in actor-based programs reported in literature. Furthermore, it analyzes the bugs to identify the patterns causing them as well as their observable behavior. Based on this taxonomy, we further analyze the literature and find that current approaches to static analysis and testing focus on communication deadlocks and message protocol violations. However, they do not provide solutions to identify livelocks and behavioral deadlocks. The insights obtained in this study can be used to improve debugging support for actor-based programs with new debugging techniques to identify the root cause of complex concurrency bugs.Comment: - Submitted for review - Removed section 6 "Research Roadmap for Debuggers", its content was summarized in the Future Work section - Added references for section 1, section 3, section 4.3 and section 5.1 - Updated citation
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