scholarly journals PROFIL OSMOTIK GELONDONGAN IKAN BANDENG (Chanos chanos Forsskal) SELAMA PROSES KULTIVASI DI TAMBAK BANDENG DESA WONOREJO KABUPATEN KENDAL

2020 ◽  
Vol 7 (2) ◽  
pp. 145
Author(s):  
Anita Karolina ◽  
Sutrisno Anggoro ◽  
Supriharyono Supriharyono

Milkfish is  euryhaline fish that can live in wide range salinity, so it will affect with osmoregulation processes. This research aimed to examine the osmotic response of milkfish fingerling during cultivation processes in brackishwater ponds at Wonorejo Village district of Kendal. The  research was conducted on July-October  2016. The cultivation process of milkfish fingerling has been cultured for 60 days in 2000 m2 brackishwater pond. The initial density of milkfish larvae was 100 individuals /m2 with a lenght size of 10 mm on average and 15 days old. Samples of milkfish fingerling were taken on the 20th, 40th and 60th days, the number of samples was 3 individuals every size. The measurement result of blood osmolarity was 460, 05 to 490.10 mOsm / l H2O higher than media osmolarity 38,98 – 194,5 mOsm/l H2O. The osmotic response of  milkfish fingerling were hyperosmotic to the hypotonic environment and osmoregulator fish.

2001 ◽  
Vol 19 (4) ◽  
pp. 579-595 ◽  
Author(s):  
D. MOSHER ◽  
B.V. WEBER ◽  
B. MOOSMAN ◽  
R.J. COMMISSO ◽  
P. COLEMAN ◽  
...  

High-sensitivity interferometry measurements of initial density distributions are reviewed for a wide range of gas-puff nozzles used in plasma radiation source (PRS) z-pinch experiments. Accurate gas distributions are required for determining experimental load parameters, modeling implosion dynamics, understanding the radiation properties of the stagnated pinch, and for predicting PRS performance in future experiments. For a number of these nozzles, a simple ballistic-gas-flow model (BFM) has been used to provide good physics-based analytic fits to the measured r, z density distributions. These BFM fits provide a convenient means to smoothly interpolate radial density distributions between discrete axial measurement locations for finer-zoned two-dimensional MHD calculations, and can be used to determine how changes in nozzle parameters and load geometry might alter implosion dynamics and radiation performance. These measurement and analysis techniques are demonstrated for a nested-shell nozzle used in Double Eagle and Saturn experiments. For this nozzle, the analysis suggests load modifications that may increase the K-shell yield.


1998 ◽  
Vol 201 (24) ◽  
pp. 3355-3366
Author(s):  
C Swanson

The euryhaline milkfish (Chanos chanos) is an excellent subject for studies of the physiological and behavioral processes involved in salinity adaptation. In this study, energy partitioning for metabolism, activity and growth, maximal activity performance and blood osmotic concentrations were assessed at two activity levels in juvenile milkfish fed equal rations and maintained at a relatively constant temperature (262 C) and at salinities(15, 35 and 55 ?) that represented a wide range of osmoregulatory challenges. Changes in the measured parameters were not consistently related to the magnitude of the trans-integumentary osmotic gradients. Routine oxygen consumption rates were high in 35 ? salinity (mean 1 s.e.m. 1678 mg O2 kg-1 h-1) and comparably low in 15 and 55 ? salinity (1336 and 1273 mg O2 kg-1 h-1, respectively). Routine activity levels (relative swimming velocity) were highest in 35 ? salinity (0. 960.04 L s-1), where L is standard length, intermediate in 15 ? salinity (0.770.03 L s-1) and lowest in 55 ? salinity (0.670.03 L s-1). Growth was significantly higher in 55 ? salinity (3.40.2 % increase in wet body mass per day) than in 35 ?salinity (2.40.2 % increase per day) and intermediate in 15 ? salinity(2.90.5 % increase per day). Maximum swimming velocities decreased with increases in salinity, from 9.90.7 L s-1 in 15 ? salinity to 6.60. 5 L s-1 in 55 ? salinity. Sustained swimming activity above routine levels for 2 h resulted in an increase in blood osmotic concentrations in milkfish in 55 ?salinity, but osmoregulation was re-established during the second 2 h of activity. Thus, patterns of variation in metabolic rate and growth were largely parallel to variations in routine activity although, comparing 15 and 55 ? salinity, elevated maintenance costs for osmoregulation at the high salinity were detectable. Reduced osmoregulatory abilities and reductions in maximal swimming performance suggest that high salinity may constrain activity. The results demonstrate that investigations of salinity adaptation in euryhaline fishes should take into account the interactive effects of salinity on physiology and behavior.


2019 ◽  
Vol 86 (sp1) ◽  
pp. 43
Author(s):  
Christina Lalramchhani ◽  
Changaramkumarath Paran Balasubramanian ◽  
Akshay Panigrahi ◽  
Tapas Kumar Ghoshal ◽  
Sanjoy Das ◽  
...  

2020 ◽  
Vol 6 (2) ◽  
pp. 127-136
Author(s):  
Ihor Vasylkivskyi ◽  
◽  
Vasyl Fedynets ◽  
Yaroslav Yusyk

The article presents the designs of a number of devices for measuring the thermal conductivity of solids developed using the new methodological approaches proposed by the authors, which enable measurements in a wide range of thermal conductivity values with better accuracy. The proposed approaches rely on the principle of invariance, which consists in ensuring the compensation of the effect of various non-informative parameters on the measurement result. For calculating the developed thermometric bridge circuits (balanced, unbalanced and partially balanced), there was applied the theory of thermal circuits based on the similarity between heat transfer and electricity transfer. The design of thermometric devices based on thermometric bridge circuits makes it possible to raise significantly the accuracy of measuring thermophysical properties of materials due to the reduced errors stemming from the effect of non-informative parameters on the measurement result. This, in turn, allowed the extended measurement range for the thermal conductivity, increased reliability and reduced cost of the devices owing to the simplified measuring circuit.


2019 ◽  
Vol 6 (2) ◽  
pp. 125
Author(s):  
Lailatul Lutfiyah, Rr Juni Triastuti Endang Dewi Masithah, Win Darmanto

Abstract Tilapia fish belonged to the euryhaline fish, which has wide range tolerance in salinity (freshwater euryhaline fish has salinity tolerance >8 ppt). Incidence of fish skeletal abnormalities could be the response of the environment influence such as salinity, temperature and hypoxia. This research uses five treatments : 0,5 10, 15, 20 ppt. The results showed that the highest abnormalities found on the treatment of 15 ppt and 20 ppt, while the lowest for the treatment of abnormalities of 10 ppt. The best result to be used in the brackish nila aquaculture is 10-15 ppt in salinity.


2021 ◽  
Author(s):  
Xiaoyun Lin ◽  
Hanghai Zhou ◽  
Feng Zeng ◽  
Lijia Jiang ◽  
Edidiong Okokon Atakpa ◽  
...  

Abstract In this study, a biosurfactant producing strain, Rhodotorula sp. CC01 was isolated using landfill leachate as nitrogen source, while olive oil was determined as the best sole carbon source for producing biosurfactants. The biosurfactant produced by Rhodotorula sp. CC01 was characterized as glycolipids with a critical micelle concentration of 70 mg/L, which showed stability over a wide range of pH (2–12), salinity (0–100%), and temperature (20–100°C). During the cultivation process, the surface tension decreased from 51.87 to 28.20 mN/m in 15 h, and the removal efficiency of NH4+-N reached 84.2% after 75 h cultivation with a maximum NH4+-N removal rate of 3.92 mg·L-1·h−1. In addition, Rhodotorula sp. CC01 has proven to be of great potential in remediating petroleum hydrocarbons, as revealed by chromogenic assays. The findings of this study prove a cost-effective strategy for the production of BS by yeast through the utilization of landfill leachate.


2020 ◽  
Vol 42 (4) ◽  
pp. 5-18
Author(s):  
V.P. Babak ◽  
A.A. Zaporozhets ◽  
Y.V. Kuts ◽  
L.M. Scherbak

It is known that deterministic and probabilistic models of measured quantities, processes and fields, as well as physical and probabilistic measures, make it possible to form a measurement result, to provide it with the properties of objectivity and reliability. On their basis, the measuring instruments necessary for obtaining new knowledge and maintaining the process of technological development of production are being developed and improved. Therefore, the issues of improving and developing models and measures in measurement methodology play an increasingly important role in achieving high measurement accuracy and expanding the areas of their application. The article is devoted to the features and results of the study of the application of models and measures in measurements. It is shown that the physical correctness and the need for setting up measuring experiments, performing tasks and conditions for their implementation, substantiating adequate models and measures significantly affect the obtained measurement result. The features of the modern methodology of using models of signals and fields and measures for evaluating the results of measuring physical quantities, including thermophysical ones, which are represented by random quantities and angles are presented. In the general case, a measure is a countably additive set function that acquires only negative values ​​in any way, including infinity. The use of charge as a mathematical model significantly expands the boundaries of the practical application of the methods of measure theory in metrology. Examples of probabilistic measures on a straight line, on a circle and a charge, as well as physical measures are considered. The concept of coordination of physical and probabilistic measures has been substantiated with the aim of a unified approach to assessing the measurement result. The joint use of physical and probabilistic measures for the formation of a measurement result allows to a certain extent overcome the problem of measurement homomorphism. An example of using a set of physical and probabilistic measures in the hardware and software modules of information and measuring systems is given. The probabilistic normalized measure is a non-physical degree, but a measure of the totality of the action of various random factors on the value and characteristics of data and the result of measurements when they are carried out. The use of a probabilistic measure in the statistical processing of measurement data makes it possible to increase the accuracy of the measurement result compared to the accuracy of the measurement data. The degree of information protection during measurements is complex. The measure is formed by many factors, the action of most of which is of a random nature. This makes it possible to determine such a measure as probabilistic, which can be applied both for individual operations, for example, transmission of measurement data via communication channels, registration of the measurement result, and for the entire measurement process as a whole. The stochastic approach in the theory of measurements is of particular importance in the case of measurements of physical quantities that have a pronounced probabilistic nature, for example, in the case of nano-measurements, the study of quantum effects, and the like. Currently, the use of the SI international system of units at the quantum level and the concept of uncertainty for evaluating measurement results, which are the foundation of measurement practice, requires a wide range of theoretical and simulation studies of measurement processes in various subject areas to form a unified measurement methodology.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Muhammad A. Kurnianto ◽  
Harsi D. Kusumaningrum ◽  
Hanifah N. Lioe ◽  
Ekowati Chasanah

Bacteriocin-like inhibitory substances (BLIS) have sparked great interest because of their promising use in food as natural antimicrobial agents. In this work, six Streptomyces isolates obtained from the gut of Chanos chanos demonstrated their ability to produce extracellular metabolites with inhibitory activity against Salmonella enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus. Exposure of the extracellular metabolites to proteolytic enzymes (i.e., proteinase-K, trypsin, and pepsin) revealed high sensitivity and confirmed their proteinaceous nature. The metabolites were stable at high temperatures (up to 100°C for 30 min) and a wide range of pH (pH 2.0–7.0). Fractionation of the crude BLIS by filtration yielded three fractions based on molecular weight: <3 kDa, 3–10 kDa, and >10 kDa. Analysis of the antibacterial activity of these fractions showed increased specific activity, especially in the fraction with a molecular weight (MW) of <3 kDa, relative to the crude sample. The fraction with MW < 3   kDa had minimum inhibitory and bactericidal concentrations in ranges 0.04–0.62 mg·mL−1 and 0.08–1.25 mg·mL−1, respectively. This fraction also showed better temperature and pH stability compared with crude BLIS. Brine shrimp toxicity assay revealed that this fraction has moderate toxicity with a 50% lethal concentration of 226.975 μg·mL−1 (i.e., moderate toxicity) to Artemia salina. Identification of the peptide sequences of this fraction by liquid chromatography–tandem mass spectrometry yielded 130 proteins with retention times of 15.21–19.57 min. Eleven proteins with MWs of 1345.66–2908.35 Da and composed of less than 30 amino acid residues with high hydrophobicity (15.34–26.22 kcal·mol−1) appeared to be responsible for the antibacterial activity of the fraction. This study revealed the potential application of BLIS from Streptomyces, especially BLIS SCA-8, as antibacterial agents.


2021 ◽  
Vol 2 (9 (110)) ◽  
pp. 27-36
Author(s):  
Volodymyr Shcherban’ ◽  
Ganna Korogod ◽  
Oksana Kolysko ◽  
Mariana Kolysko ◽  
Yury Shcherban’ ◽  
...  

Studies of the effect of normalized radiation fluxes on the measurement result revealed the most influential one. The value of the normalized flow F0 was shown to have a greater effect on the relative measurement error than ΔF0. This allows investigating the relationship between the controlled Fx and the normalized flow F0. Experimental studies have confirmed that by a threefold increase in the normalized flow F0 relative to the controlled flow Fx, it becomes possible to increase the measurement accuracy in a wide range. In particular, it was found that at the flux value F0=0.16×10-3 W, it becomes possible to measure the controlled flow in a wider range Fх=(0.16×10-3÷0.97×10-3) W with a relative error of thousandths of a percent. The effect of the reproduction error on the measurement result under the condition of a threefold increase in the normalized flow F0 relative to the controlled flow Fх is shown. It was found that an increase in the reproduction error of the normalized radiation fluxes by 1 order leads to a narrowing of the range in which the value of the relative error tends to zero. It is shown that in the absence of a threefold increase in the normalized flow F0, an increase in the reproduction error of the normalized flows by 1 order leads to individual cases of reduction in the relative error to small-order values. The latter, by the way, applies to cases where the ratio between the normalized F0 and controlled flow Fx, as 3 to 1, is ensured. It is shown that the reproduction error of the dark flow does not affect the measurement result.Thus, there is reason to believe that it is possible to expand the measurement range, in which the value of the relative error is thousandths of a percent, even for 1 measurement cycle


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