1,720,966 research outputs found
Perubahan Jaringan Hati ikan Pari Kembang Dasyatis kuhlii akibat Logam Berat Merkuri (Hg)
No full textIkan Pari Kembang Dasyatis kuhlii sebagai organisme dasar perairan mengalami banyak akumulasi bahan pencemar di perairan yang mengendap ke bawah. Penelitian ini dilakukan untuk melihat perubahan jaringan hati yang disebabkan oleh cemaran Merkuri (Hg). Dilakukan pada 5 bak, yaitu bak A sebagai kontrol, bak B dengan konsentrasi 0.025 ppm, bak C dengan konsentrasi 0.05 ppm, bak C dengan konsentrasi 0.1 ppm dan bak D dengan konsentrasi 0.2 ppm. Hasilnya adalah beberapa perubahan berupa kerusakan jaringan hati atrophy, cloudy swelling, vacuola degeneration bahkan necrosis atau jaringan hati sudah mengalami kematian. Kerusakan-kerusakan tersebut dapat menurunkan bahkan menghilangkan fungsi hati sebagai penyerap racun dan dapat mengakibatkan kematian. Ikan yang mengkonsumsi merkuri tidak mampu menguraikannya, sehingga apabila ikan tersebut dikonsumsi oleh manusia, maka masih membahayakan bagi manusia karena dapat mengalami keracunan merkuri (hydrargyria atau mercurialism) yang akan mempengaruhi penglihatan, pendengaran, pengucapan bahkan dapat menimbulkan kematia
Perubahan Jaringan Hati Ikan Pari Kembang ( DASYATISKUHLI) Akibat Merkuri (HG)
Full text linkBlue Spotted Ray (Dasyatis kuhlii) as the demersal organisms has a lot of accumulation of pollutants in the water that settles to the bottom. This study was conducted to look at the liver tissue alteration of Blue Spotted Ray caused by contamination of mercury (Hg). Performed on 5 tanks. Tank A as a control, tank B with concentration 0.025 ppm, tank C with concentration of 0.05 ppm, tank D with concentration 0.1 ppm and tanks E with concentration 0.2 ppm. The result is alteration on the liver tissue in the form of atrophy, cloudy swelling, vacuolization degeneration and even necrosis or death of liver tissue already. The alteration can reduce and eveneliminate the function of the liver as a toxin absorbent and can lead to death
PEUBAH KUALITAS AIR YANG MEMPENGARUHI PERTUMBUHAN RUMPUT LAUT (Gracilaria verrucosa) DI TAMBAK TANAH SULFAT MASAM KECAMATAN ANGKONA KABUPATEN LUWU TIMUR PROVINSI SULAWESI SELATAN
Full text linkRumput laut (Gracilaria verrucosa) telah dibudidayakan di tambak tanah sulfat masam dengan kualitas dan kuantitas produksi yang relatif tinggi. Oleh karena itu, dilakukan penelitian yang bertujuan untuk mengetahui peubah kualitas air yang mempengaruhi laju pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur Provinsi Sulawesi Selatan. Pemeliharaan rumput laut dilakukan di 30 petak tambak terpilih selama 6 minggu. Bibit rumput laut dengan bobot 100 g basah ditebar dalam hapa berukuran 1,0 m x 1,0 m x 1,2 m. Peubah tidak bebas yang diamati adalah laju pertumbuhan relatif, sedangkan peubah bebas adalah peubah kualitas air yang meliputi: intensitas cahaya, salinitas, suhu, pH, karbondioksida, nitrat, amonium, fosfat, dan besi. Analisis regresi berganda digunakan untuk menentukan peubah bebas yang dapat digunakan untuk memprediksi peubah tidak bebas. Hasil penelitian menunjukkan bahwa laju pertumbuhan relatif rumput laut di tambak tanah sulfat masam berkisar antara 1,52% dan 3,63%/hari dengan rata-rata 2,88% ± 0,56%/hari. Di antara 9 peubah kualitas air yang diamati ternyata hanya 5 peubah kualitas air yaitu: nitrat, salinitas, amonium, besi, dan fosfat yang mempengaruhi pertumbuhan rumput laut secara nyata. Untuk meningkatkan pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur dapat dilakukan dengan pemberian pupuk yang mengandung nitrogen untuk meningkatkan kandungan amonium dan nitrat serta pemberian pupuk yang mengandung fosfor untuk meningkatkan kandungan fosfat sampai pada nilai tertentu, melakukan remediasi untuk menurunkan kandungan besi serta memelihara rumput laut pada salinitas air yang lebih tinggi, tetapi tidak melebihi 30 ppt.Seaweed (Gracilaria verrucosa) has been cultivated in acid sulfate soil-affected ponds with relatively high quality and quantity of seaweed production. A research has been conducted to study water quality variables that influence the growth of seaweed in acid sulfate soil-affected ponds of Angkona Sub-district East Luwu Regency South Sulawesi Province. Cultivation of seaweed was done for six weeks in 30 selected brackishwater ponds. Seeds of seaweed with weight of 100 g were stocked in hapa sized 1.0 m x 1.0 m x 1.2 m. Dependent variable that was observed was specific growth rate, whereas independent variables were water quality variables including light intensity, salinity, temperature, pH, carbondioxide, nitrate, ammonium, phosphate, and iron. Analyses of multiple regressions were used to determine the independent variables which could be used to predict the dependent variable. Research result indicated that relative growth rate of seaweed in acid sulfate soils-affected brackishwater ponds ranged from 1.52% to 3.63%/day with 2.88% ± 0.56%/day in average. Among nine observed water quality variables, only five variables namely: nitrate, salinity, ammonium, phosphate and iron influence significantly on the growth of seaweed in acid sulfate soils-affected brackishwater ponds. The growth of seaweed in acid sulfate soils-affected brackishwater ponds of Angkona District East Luwu Regency, can be improved by using nitrogen-based fertilizers to increase ammonium and nitrate contents and also fertilizers which contain phosphorus to improve phosphate content to a certain level. Pond remediation to decrease iron content and also rearing seaweed at higher salinity (but less than 30 ppt) can also be alternatives to increase the growth of seaweed
IDENTIFICATION OF SUITABLE BLUE SWIMMER CRAB SPECIES COMPLEX FOR REARED IN BRACKISH WATER POND
No full textBlue swimmer crab is a species complex with various characteristics. This study aims to access the potential of blue swimmer crab to be used as aquaculture animals by selecting the species were most suitable reared in brackish water pond. In this study, twenty wild berried female regardless of species were naturally hatched in the hatchery and their larva reared until crab instar. Then, the crab seeds were reared in brackish water pond for three months. Observation was conducted at harvest on number and size in carapace width for each identified species. Species identification based on the color, pattern of white spots on the carapace, and the number of spines on cheliped merus. Suitability as aquaculture animals is characterized by a high number and large size of crab. The results showed that there were at least three species of blue swimmer crab survival in brackish water pond after three months rearing period. The species were Portunus pelagicus, P. armatus, and P. reticulatus. There were variations in number and sizes of harvest among these species. Number of harvested crab were 66% of P. Pelagicus, medium size group (average carapace width of 97 mm), 31% of P. armatus, largest size group (average carapace width 108 mm) and 3% of P. reticulatus, smallest size group (average carapace width of 90 mm). It is concluded that P. pelagicus and P. armatus were the two species are suitable for aquaculture in brackish water pond. Domestication to reviews these two species is important for its culture development
Effect of Dietary Taurine Enrichment Levels on Growth Performance, Survival and Metamorphosis of Humpback Grouper Cromileptes altivelis
Full text linkThe effect of feeding rotifers and Artemia enriched with taurine on the growth performance, survival and metamorphosis of humpback grouper Cromileptes altivelis larvae was investigated. Rotifers and Artemia nauplii were enriched with a commercial taurine supplement at four levels: 0 gL-1 (T-0), 1 gL-1 (T-1), 2 gL-1 (T-2), and 3 gL-1 (T-3). The larvae were fed the enriched rotifers from 2 days after hatching (DAH) to 20 DAH and enriched Artemia nauplii from 14 DAH to 60 DAH in triplicate. The growth of larvae was significantly higher in T-1 and T-2 than that of T-0. The survival rate of larvae was significantly higher in T-1, T-2 and T-3 than that of T-0. The percentage of flexion stage larvae of T-1 group was significantly higher than that of T-0 group at 15 and 20 DAH. Stage-1 larvae of metamorphosis firstly appeared in all of the groups at 30 DAH, however, at 45 DAH stage-2 larvae were significantly more abundant in T-1 than other groups. Further, at 55 DAH percentage of stage-3 larvae was significantly higher in T-1 group than that of T-3 and T-0 and thereafter (60 DAH) remained significantly higher than T-0. Therefore, the larvae fed taurine-enriched rotifers and Artemia nauplii of 1 gL-1 (T-1) showed the best growth performance, survival and metamorphosis which were significantly higher than those of other treatments (P<0.05). These results suggest that taurine is an essential nutrient for humpback grouper larvae and taurine enrichment of rotifers and Artemia is an effective method of enhancing the growth performance, survival and metamorphosis success o
GROWTH PERFORMANCE AND MEAT QUALITY OF DOMESTICATED BLUE SWIMMING CRAB (Portunus pelagicus)
No full textBlue Swimming Crab (Portunus pelagicus) is one of the commercial crabs traded widely around the world. But, crab aquaculture has not made a significant contribution in meeting the increasing overseas market demand. Some constraints in crab cultivation were high mortality, low and variable growth rate, and low of meat quality. The aims of this research were to produce a superior broodstock through domestication and selective breeding. Superior broodstock was expected to produce a high quality offspring with a high growth rate, high survival rate, and high quality of meat.\ud
The study was conducted over two years (2013-2014) at educational farms of Hasanuddin University, located in Barru Regency, South Sulawesi Province of Indonesia. The research consist of: 1) collection of wild crab for broodstock, 2) spawning, hatching, and larval rearing in backyard hatchery until zoea-5, 3) grow out in brackish water pond for 90 days, 4) selection of broodstock candidate based on size and resistance to evironmental farming. 5) domesticated broodstock rearing. Selective breeding for fast growing traits was carried out up to three generations. Parameters measured were carapace width, weight, growth, and meat quality include the chemical composition, texture, and crab meat yield.\ud
The result showed that the third generation (G3) of domesticated blue swimming crab has a faster growth rate than the first generation (G1). After 90 days rearing in brackish water pond, 78 % of G3 reached 100 mm average of carapace width while the G1 was only 16%. Result of proximate (Table 1), texture, yield, and organoleptic analysis showed that the meat quality of domesticated and wild blue swimming crab were relatively similar.\ud
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Table 1. Chemical composition of domesticated and wild blue swimming crab meat\ud
Sample Fraction Crab Sample Composition (%)\ud
Crude Protein Fat Crude Fiber Moisture Ash Nitrogen Free Extracts\ud
Fresh Domesticated 15.89 0.08 0.04 79.85 1.31 2.84\ud
Wild 14.18 0.08 0.03 81.85 2.55 1.32\ud
Dry weight Domesticated 78.85 0.41 0.18 - 2.04 18.53\ud
Wild 78.25 0.43 0.17 - 1.74 19.41\ud
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The conclusion of this study was blue swimming crab domestication with selective breeding resulted excel in growth and quality of meat. The use of domesticated G3 broodstock has a good prospects for aquaculture
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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