bluuebunny/crossref_metadata_2025 huggingface dataset:
Shifted relationship between the Pacific decadal oscillation and western North Pacific tropical cyclogenesis since the 1990s
Authors: Zhou Cong , Wu Liguang , Wang Chao , Cao Jian
Published: December 2023

The Pacific Decadal Oscillation (PDO) and Pacific Meridional Mode (PMM) are prominent climate modes in the North Pacific with well-established impacts on tropical cyclone (TC) genesis in the western North Pacific (WNP) basin. While previous research has primarily focused on the roles of the PDO and PMM in regulating TC genesis through the modification of large-scale environmental factors, this study investigates the evolving influence of the PDO on WNP TC genesis since the 1950s. Remarkably, our analysis reveals a shift in the PDO-TC genesis relationship, transitioning from a significant negative correlation to a significant positive correlation since the 1990s. This shift is attributed to variations in the specific large-scale factors through which the PDO affects TC genesis. Furthermore, this study suggests that these changes appear to be linked to the PMM strengthening on the interdecadal timescale in recent decades. The linkage of the PMM strengthening to the PDO-related atmospheric circulation is further confirmed by the results of a 500 year pre-industrial numerical experiment, suggesting that the PMM strengthening may result from natural internal variability. The results underscore the non-stationary relationship between PDO and WNP TC genesis, with the PMM intensity probably influencing their relationship.
Convergence of the logarithm of the characteristic polynomial of unitary Brownian motion in Sobolev space
Authors: Forkel Johannes , Sauzedde Isao
Published: December 2023

We prove that the convergence of the real and imaginary parts of the logarithm of the characteristic polynomial of unitary Brownian motion toward Gaussian free fields on the cylinder, as the matrix dimension goes to infinity, holds in certain suitable Sobolev spaces, whose regularity we prove to be optimal. Our result can be seen as the natural dynamical analogue to the stationary result for a fixed time by Hughes et al (2001 Commun. Math. Phys.
220 429–51). Further our result is related to the work of Spohn (1998 Markov Processes and Related Fields vol 4), from which the identification of the above limit as the Gaussian free field first followed, albeit in a different function space.
A novel coupling technique based on thermal desorption gas chromatography with mass spectrometry and ion mobility spectrometry for breath analysis
Authors: Schanzmann Hannah , Ruzsanyi Veronika , Ahmad-Nejad Parviz , Telgheder Ursula , Sielemann Stefanie
Published: December 2023

Exhaled breath analysis is evolving into an increasingly important non-invasive diagnostic tool. Volatile organic compounds (VOCs) in breath contain information about health status and are promising biomarkers for several diseases, including respiratory infections caused by bacteria. To monitor the composition of VOCs in breath or the emission of VOCs from bacteria, sensitive analytical techniques are required. Next to mass spectrometry, ion mobility spectrometry (IMS) is considered a promising analytical tool for detecting gaseous analytes in the parts per billion by volume to parts per trillion by volume range. This work presents a new, dual coupling of thermal desorption gas chromatography to a quadrupole mass spectrometer (MS) and an IMS by operating a simple splitter. Nearly identical retention times can be reached in the range of up to 30 min with slight deviations of 0.06 min–0.24 min. This enables the identification of unknown compounds in the IMS chromatogram using unambiguous mass spectral identification, as there are still no commercially available databases for IMS. It is also possible to discriminate one of the detectors using the splitter to improve detection limits. Using a test liquid mixture of seven ketones, namely 2-butanone, 2-pentanone, 2-hexanone, 2-heptanone, 2-octanone, 2-nonanone, and 2-decanone with a concentration of 0.01 g l−1 reproducibilities ranging from 3.0% to 7.6% for MS and 2.2%–5.3%, for IMS were obtained, respectively. In order to test the system optimized here for the field of breath analysis, characteristic VOCs such as ethanol, isoprene, acetone, 2-propanol, and 1-propanol were successfully identified in exhaled air using the dual detector system due to the match of the corresponding IMS, and MS spectra. The presented results may be considered to be a starting point for the greater use of IMS in combination with MS within the medical field.
The effects of Chaetoceros sp. meal as a feed supplement on color expression, growth performance and survival rate of discus (Symphysodon discus)
Authors: Fauziah A , Arifin M Z , Widodo A , Cahyanurani A B , Halim A M , Aonullah A A
Published: December 2023

Discus fish is one of the ornamental fish that has high economic value based on its color characteristic. To increase fish body color, its need carotenoids obtained from feed. Chaetoceros sp. is a natural food rich in carotenoids, especially fucoxanthin. This study aims to evaluate the effect of diets consisting of 0% (control), 5%, 10% and 15% Chaetoceros sp. powder on color expression (brightness value and color density), growth performance and survival rates of Symphysodon discus. Chaetoceros sp. powder was added into the basal diet. One hundred of discus fish with an average length of 0.5 cm were cultured for 56 days. The result showed that the supplementation of 5-15% Chaetoceros sp. powder had no significant effects on the survival rate and the brightness value of discus fish. The increasing of Chaetoceros sp. powder supplementation showed a lower rate of growth performance compared to control (p<0.05), however the color density was observed to increase significantly at 15% Chaetoceros sp. treatment (p<0.05). As the conclusion, this study showed that dietary Chaetoceros sp. could improve the color expression especially the color density of discus fish and the supplementation level was suggested to be 10% Chaetoceros sp powder.
Stress response and oxygen consumption level of vaname shrimp (Litopenaeus vannamei) infested by Ciliata pathogens on culture system with high stocking densities
Authors: Marista M , Mahasri G , Kusnoto
Published: December 2023

One of the technology used to increase the production of vaname shrimp is by culture system with high stocking densities. Disease cases that are often reported to attack vaname shrimp in rearing with high stocking densities are derived from ectoparasites Ciliata pathogens such as Vorticella sp., Zoothamnium sp. and Epistylis sp. This study aimed to determine the effect of high stocking density, rearing time and the interaction between high stocking density and rearing time on the stress response (blood glucose level) and oxygen consumption level of vaname shrimp (Litopenaeus vannamei) infested by Ciliata pathogens. This study used an experimental method using a Completely Randomized Design (CRD) with a 3×5 factorial pattern consisting of 3 treatments and 6 replications. Factor A is high stocking density (10 prawns/10L, 15 prawns/10L and 20 prawns/10L) and factor B is rearing time (day-0, 2, 4, 6 and 8). The results of this study showed that high stocking density and rearing time had a significant effect (p<0.05) and there was a significant interaction (p<0,01) with a high stocking density of 20 prawns/10L and rearing time on day-8 of increasing blood glucose level and oxygen consumption level of vaname shrimp infested by Ciliata pathogens.
Study of the population Vibrio Sp. on the health of vanname shrimp (Litopenaeus vannamei) in Cv. Reksa Bumi Situbondo
Authors: Setyastuti TA , Suseno DN , Rumayasa IGP , Hakimah N , Hilmy FM
Published: December 2023

Vannamei shrimp is one of the commodities of excellence in aquaculture. The production system is carried out mass with high stocking density causes vannamei shrimp culture susceptible to disease. One type of disease that can cause mass mortality in cultured shrimp is vibriosis. This activity aims to study the abundance of bacterial populations Vibrio sp. and its effect on the health of Vanname Shrimp (Litopenaeus vannamei) at CV. Reksa Bumi Situbondo East Java. Identification of Vibrio sp. performed on TCBS agar media. Clinical symptoms of shrimp that are attacked by vibriosis. Besides the attack vibrio sp. produce clinical symptoms such as body flushing, red swimming legs and red tail. The abundance of Vibrio sp. that exceeds the threshold causes WFD disease attacks and IMNV. The high abundance of Vibrio sp. caused by conditions unfavorable aquatic environment due to entering the transition season resulting in sudden changes in water quality and increase the abundance of bacteria.
Effect of Probiotics in Recirculating Aquaculture System (RAS) on the Concentration of Ammonia, Nitrite, and Nitrate in the Aquaculture of Catfish (Clarias sp.)
Authors: Nurhasanah A , Rahardja B S , Prayogo
Published: December 2023

The purpose of this research is to determine the effect of probiotic administration on ammonia, nitrite, and nitrate levels in catfish cultivation (Clarias sp.) with the RAS system. The research was conducted in February – March at the Anatomy Laboratory and chemical laboratory of the Faculty of Fisheries and Marine Airlangga University. This study was conducted experimentally using the RAL method consisting of 5 treatments four replays, namely control treatment (P0), probiotic dose 0.5 mL/L (P1), probiotic dose 1 mL/L (P2), probiotic dose 1.5 mL/L (P3), and probiotic dose 2 mL/L (P4). Data analysis is processed using ANOVA and DMRT. The result of this study was the administration of probiotics with the bacterium Nitrosomonas sp. And Nitrobacter sp. with different doses has an effect (p<0.05) on the concentration of ammonia, nitrite, and nitrates.
Iodium fortification on traditional salt with spray different potassium iodate
Authors: Salsabila H F , Alamsjah M A , Pujiastuti D Y
Published: December 2023

The purpose of this study was to increase the iodine content of traditional salt after fortification of iodine with potassium iodate spray. In addition, this study also aims to determine the NaCl content and water content of traditional salt after potassium iodate fortification is carried out. This research is also expected to provide an alternative solution to increase the iodine content of salt by fortification of potassium iodate. And hopefully this research can help the government in handling cases of Iodine Deficiency Disorder in Indonesia. The treatments used were the addition of KIO3 solution with different weight of traditional salt P1 (50 gram traditional salt : 3 ml KIO3 solution), P2 (33,33 gram traditional salt : 3 ml KIO3 solution) dan P3 (25 gram traditional salt : 3 ml KIO3 solution). Potassium iodate fortification in traditional salt affects iodine and NaCl levels. Fortification of 3 ml potassium iodate with a salt weight of 25 grams (P3) produced the highest iodine content with an average of 64.74 ppm, an average NaCl content of 86.14 %, and an average water content of 3.7%.
Testing the antibacterial effectiveness of mangosteen peel extract (Garcinia mangostana L) against Aeromonas hydrophila Bacterial infection in dumbo catfish (Clarias gariepinus)
Authors: Cahya B , Nirmala D , Triantoro B
Published: December 2023

Plants belonging to the Clusiaceae species are Garcinia mangostana Linn (mangosteen fruit). The skin layer of this fruit has been used as a traditional medicine for wound healing, topical infections. Mangosteen rind contains compounds including mangostin, mangostenol, mangostinon A, mangostenon B, trapezifolixanthone, tovofillin B, alpha mangostin, beta mangostin, garsinon B, mangostanol, flavonoids, epicatechin. Gartanin, gamma mangostin, garsinon E, epicatechin. Farming African catfish (Clarias Gariepinus) when facing serious problems such as fish are susceptible to disease, mainly due to bacteria. One type of bacteria that causes the disease is Aeromonas hydrophila. This type of bacteria can cause high fish mortality in African catfish (Clarias Gariepinus) of various sizes. The purpose of this study was to determine the effect of mangosteen rind extraction on the growth of Aeromonas hydrophila bacteria in vitro, as well as the 96-hour Lethal Dose (LD50) value of mangosteen rind extract after exposure to African catfish (Clarias Gariepinus). In this study, the antibacterial activity of the material was tested in vitro with concentrations of 0%, 1.56%, 3.125%, 6.25%, 12.5%, 25% and 50%.
Characterization of Bacillus subtilis (BR 610) isolated from the intestines of Rabbitfish, Siganus guttatus, maintained in Floating Net at Awerange Bay, Barru
Authors: Tampangallo B R , Anshary H , Wulan S , Syah R
Published: December 2023

The use of some species of Bacillus as a probiotic has been widely reported. In general, using probiotics in the exact isolation location will improve the performance of these probiotics. This study aims to characterize the Bacillus subtilis (BR610) isolate, successfully isolated from the intestines of Rabbitfish previously cultivated in the floating net of Awerange bay, Barru, South Sulawesi. The research includes morphological characterization of BR610 isolates, activity tests of amylase, cellulose, and proteinase enzyme. BR610 isolate inhibition test against several types of pathogenic bacterial isolates (Vibrio harveyi, V. parahaemolyticus, V. alginolitycus, and Streptococcus) as well as BR610 isolate resistance test against various kinds of antibiotics. The results showed that the Bacillus subtilis (BR610) has a spherical morphology, wavy edges, flat elevation, and is cream-white in color. BR610 can produce the enzyme amylase 20.36±17.8mm, proteinase 14.2±6.7mm, and Cellulose 20.9±2.7mm. These isolates can also inhibit the growth of V. harveyi (13.0±0.3mm), V. alginolyticus (15.1±2.8mm), V. parahaemolyticus (14.7±2.7mm), and Streptococcus (17.6±1.6mm). Bacillus subtilis BR610 is still worthy of being used as an environmentally friendly probiotic because it is still sensitive to several types of antibiotics tested.
Identification, prevalence and intensity of ectoparasite in sand lobster (Panulirus homarus) cultivated in floating cages (floating net cage) and bottom cage (bottom cage)
Authors: Septian G , Ulkhaq M F , Kismiyati
Published: December 2023

Lobster (Panulirus homarus) is one of the marine fishery commodities that is gaining popularity and has been widely cultivated in Indonesia. This is because lobster has great business prospects and is one of the important commodities and has high economic value. Lobster cultivation can now be done in various systems including floating net cages, bottom cages and ponds. The problem that is often faced by cultivators is the emergence of diseases in the lobster cultivation cycle caused by an unbalanced interaction between lobster conditions, the environment, and pathogens. This is one of the main problems in lobster cultivation that can interfere with the survival of lobsters and can also cause death. Research on ectoparasite infection in Sand Lobster (Panulirus homarus) cultured in floating net cages and bottom cages aims to identify the types of ectoparasites and calculate the prevalence and intensity of ectoparasites infecting sand lobster (Panulirus homarus). The method used in this study is a survey method. The sampling method was carried out by random sampling method and the method of analysis and presentation of data using descriptive methods. The main parameters observed in this study were the type of ectoparasites, prevalence and intensity values of sand lobster (Panulirus homarus) infected with ectoparasites, while the supporting parameter was lobster size. The ectoparasite found to infest the sand lobster (Panulirus homarus) was Octolamis angulata. The highest prevalence value was obtained in cultivation using floating net cages of 53,3% which belonged to the Frequently category (commonly) and the highest intensity value was obtained in cultivation using floating net cages of 30,1 which belonged to the Medium category (currently). It is necessary to conduct further studies on Octolasmis species based on the DNA chain arrangement and description of tissue damage due to Octolasmis infestation
Study on the quality of fesh swanggi (Priacanthus macracanthus) at fish auction places (TPI) Brondong, PPN Brondong, Lamongan. East Java.
Authors: Harahap A H , Sahidu A M , Isroni W
Published: December 2023

This study aims to analyze and describe the quality of swanggi fish and determine the external factors that affect the quality of swanggi fish (Priacanthus macracanthus) at the Fish Auction Place (TPI) Brondong, Lamongan, East Java. The type of research used is descriptive survey research. The test parameters in this study were organoleptic test, pH test and formalin test to analyze and describe the quality of swanggi fish. In addition, a causal analysis was also carried out to determine the externalfactors that affect the quality of swanggi fish. This research was carried out at the Fish Auction Place (TPI) Brondong, PPN Brondong, Lamongan, East Java on February 01 to February 24, 2022. The results of organoleptic and pH testing of swanggi fish were declared still fit for consumption but found 68 samples. formalin positive swanggi fishor 24.29% of the total test samples. Meanwhile, the external factor of the decline in the quality of swanggi fish is strongly influenced by the lack of monitoring and evaluationof good fish handling practice (CPIB).
Dynamics of water quality in grouper nurseries with flow through, recirculation and bioremediation systems
Authors: Ismi S , Astari B , Mastuti I
Published: December 2023

The flowthrough system, a daily water exchange, has high risk in fluctuation of water quality. Moreover, the risk could impact the seed productions, especially in grouper nurseries. Recirculation and bioremediation systems are satisfying technique to maintenance the water quality. The aim of this research was to analyse the effectiveness of flowthrough, recirculation and bioremediation systems in grouper nursery for water quality and grouper seed production. The research was conducted with three treatments and four replications as follows: A. flowthrough, B. recirculation and C. recirculation with bioremediation. The research was conducted in a completely randomized design for 40 days. The best water quality in treatment C: Salinity ranged from 30-35 g/L, ammonia reached 0.0726-1.8978 mg/L, and inhibited the growth of Vibrio spp. up to 2.580 CFU/mL. The results showed that the best average value was obtained by treatment C with a survival rate of 94.8±0.4%, length growth rate of 0.110±0.003 cm/day, weight growth rate of 0.175±0.013 g/day, specific length growth rate of 2.02±0.04%, specific weight growth rate 5.56±0.28%, total length 8.0 cm, total weight 7.91 g, and feed conversion ratio 0.73±0.07.
First photograph record of the segura’s throatspine gudgeon Belobranchus segura Keith, Hadiaty & Lord 2012 in the south of Java, Indonesia (Teleostei: Gobiiformes: Eleotridae)
Authors: Hasan V , Ottoni F P , Widodo M S , Faqih A R , Nafisyah A L
Published: December 2023

Segura’s Throatspine Gudgeon Belobranchus segura Keith, Hadiaty & Lord 2012 is an amphidromous fish from the Indo-Pacific region. In Indonesia, B. segura was distributed in Papua, Halmahera, Sulawesi (previously known as Celebes) and Java Island. The finding of this species in the lower stream river of Malang district, south of Java, Indonesia, was firstly recorded here. This study provides the photographs of a single male specimen of B. segura, the description of morphological features of a specimen and their habitat conditions.
Improvement of Red Color Quality in Koi Fish (Cyprinus carpio) Through the Addition of Rosella Extract In Feed (Hibiscus sabdariffa)
Authors: Amin A A A , Dewi N N , Rahardja B S
Published: December 2023

Koi fish (Cyprinus carpio) is one of the ornamental fish that has a beautiful body shape and color, so it has high economic value. To get koi fish production with good color quality, several supporting factors are needed, one of which is feed. In this study, rosella (Hibiscus sabdariffa) extract was used as an additive in koi fish feed. The purpose of this study was to determine the effect of rosella extract on increasing the red color of koi fish through the addition of ingredients in the feed. The study was conducted using a completely randomized design with doses of rosella extract in the feed formulation as a source of anthocyanins, namely: 0% (control), 1%, 3%, 5%. Feeding was done three times a day with a feeding rate of 5%. Maintenance was carried out for 30 days and observations of color brightness of koi fish were carried out once a week using a modified TCF (Toca color finder). The results showed that the addition of rosella extract by 5% resulted in the highest value of red brightness every week. For water quality parameters, both temperature, pH, and dissolved oxygen are still within optimal limits for koi fish.
Monitoring the distribution of phytoplankton in vannamei shrimp cultivation in intensive system, Banyuwangi, East Java, Indonesia
Authors: Zulkarnain D A , Sari L A , Sari P D W , Nindarwi D D , Arsad S
Published: December 2023

The increase in Vannamei shrimp farming is closely related to an increase in the demand for shrimp feed. At present there are many technological developments in cultivating natural feed. The natural feed here refers to plankton which can be used as natural food for every organism of larvae in waters. Conditions in water will affect the distribution pattern of phytoplankton either horizontally or vertically. As a result, it affects the abundance of phytoplankton and subsequently also affects the value of the main productivity. The purpose of study is to find out the cultivation process and to find out the types of plankton that exist in Vannamei shrimp farming ponds. Plankton observations were carried out directly with the help of a microscope and haemocytometer, while the measurement of water quality using each instrument had been prepared for each parameter. The results of plankton observations found species of Chaetoceros sp., Oocystis sp., Oscillatoria sp. and Cyclotella sp. while the water quality measurements obtained temperature (29-31°C); DO during the day (7.6-9.5 ppm) and at night (4.0-4.6 ppm); pH in the morning (7.8-8, 5) and daylight (8.1-9.0); and salinity 26-27 ppt. The application of probiotics used carbon sources derived from molasses and katul.
Study of Bawal Bintang fish (Trachinotus blochii) hatchery at the Lombok marine aquaculture, West Nusa Tenggara, Indonesia
Authors: Ramadhani A A , Sari L A , Sari P D W , Nindarwi D D , Arsad S
Published: December 2023

Bawal Bintang fish (Tracinotus blochii) has high economic value, to meet both domestic and foreign consumption needs. Bawal Bintang fish cultivation has become a commercial business to be developed because of its relatively fast growth, relatively easy maintainance, and public interest in it. The objective of this study is to find out the hatchery techniques of Bawal Bintang Fish and the obstacles that arise in their hatchery at the Lombok Marine Cultivation Fisheries, West Nusa Tenggara. The method used was descriptive with data collection including primary data and secondary data. Data collection was done by means of active participation, observation, interviews, and literature study. Bawal Bintang fish hatchery technique began with tank preparation, spawning, egg distribution, and maintenance for 20-25 days. Bawal Bintang fish hatchery included feed management, water quality monitoring, and pest and disease control. After rearing the larvae for 20-25 days or reaching seedling size, then harvesting was carried out to transfer them to the nursery tank using the RAS system. The problem that arose in the hatchery of Bawal Bintang fish was the frequent occurrence of Bawal Bintang larvae that fell from a pond.
Effect of Different Natural Feeding (Blood Worm, Silk Worm, and Water Fleas) on The Growth of Betta Fish (Betta sp.)
Authors: Iqbal M S M , Prayogo  , Han Samara S
Published: December 2023

One type of freshwater ornamental fish that is in great demand by the public is Betta fish (Betta sp.). The problem faced by Betta fish cultivation activity is inappropriate feed, for example feed with low protein content. Low protein causes slow growth in fish. This study aims to determine the effect of different natural feeds (silk worms, blood worms, water fleas, and controls) on the growth of Betta fish. The results showed that there was a significant effect (p<0.05) on the growth and specific growth rate of betta fish. However, there was no significant effect (p>0.05) of different natural feeding on the survival rate parameter. The highest result showed in treatment B (silk worm) with a weight value of 1.09 g, a length of 4.48 cm, and specific growth rate value of 1.77 ± 1.768. It can be concluded that silk worm is the best natural feeding for betta fish.
Evaluation of body performance of tilapia (Oreochromis niloticus)
Authors: Wahidah  , Rusli A , Hartinah  , Amrullah  , Dwinhoven I
Published: December 2023

Efforts to improve the quality of fish seeds can be done by using quality broodstock which includes having the right body shape. This study aimed to evaluate the body performance of male and female Sultana strain tilapia (Oreochromis niloticus) which were to be used in hatchery activities. A total of 35 male and 35 female broodstock were evaluated for body size using a ruler. Measurements of 12 morphological characters: total length (TL), standard length (SL), head length (HL), pre-dorsal length (PrDL), pre-pectoral length (PrPL), pre-pelvic length (PrPeL), pre-pelvic length (PrPeL), anal length (PrAL), anal fin length (AFL), dorsal fin base length (DFL), body height (BH), caudal peduncle height (CPH), and dorsal anal length distance (DAL). The ratio between the character values of SL, HL, PrDL, PrPL, PrPeL, PrAL, AFL, DFL, BH, CPH, DAL, and TL were analyzed descriptively. The results of the analysis showed that the average value of the ratio of length characters (SL/TL, HL/TL, DF, and AFL/TL), height character (BH/TL), and diagonal character (DAL/TL) were higher in the male broodstock than in the female broodstock. On the other hand, other length characters (PrDL/TL, PrPL/TL, PrPeL/TL, PrAL/TL) and height characters (CPH/TL) had the same values in the male and female broodstock. In general, the size of the male broodstock used tended to be larger than the female broodstock.
Microplastic abundance in Surabaya mangrove areas during the wet season
Authors: Nafisyah A L , Iswandi H S , Karisma A D , Nindarwi D D , Praveena S M , Schneider F
Published: December 2023

Plastic waste pollution is the most dominant problem in various parts of the world, and it has increased since 2020. Degraded plastic waste can accumulate in the environment, especially the mangrove ecosystem, which is a sediment trapper, allowing for the accumulation of various materials. This study was done during the wet season in December 2021 at Wonorejo mangrove areas, Surabaya, Indonesia. The aims of study were to observe the abundance of microplastic that accumulates not only in waters during high tide but also in sediments during low tide. The results will provide information about environmental pollution of the Surabaya mangrove ecosystem. Four types of microplastics were observed in water and sediment samples under the stereo microscope, i.e. fragments, fibers, films, and granules. The average abundance of microplastics in waters from five stations was 8×106 particles km-2, while in sediments (three stations) was counted as 1.5×109 particles km-2 on average. The Fourier Transform Infra-Red (FTIR) analysis was done resulting in the characteristic of microplastics. From both waters and sediments, contamination of microplastics consisted of Polyvinyl alcohol (PVA), Polyvinyl chloride (PVC), Polypropylene (PP), Polystyrene (PS), and Polyethylene (PE).
Physicochemical characteristics and organoleptic catfish sausage (Clarias sp.) with the addition of gelatin as binding agent
Authors: Yuzi R F , Saputra E , Sulmartiwi L
Published: December 2023

This study aims to determine the effect of adding gelatin as a binding agent on the physicochemical and organoleptic characteristics of catfish sausage (Clarias sp.). This study used a completely randomized design (CRD) consisting of 5 treatments with commercial fish sausage and a gelatin concentration of 0.25%, 0.5%, 1%, and 1.5% with 4 replications. The method used in this research includes proximate analysis, texture analysis, and organoleptic testing. The results of this study indicated that the addition of gelatin had a significant effect (P <0.05) on the value of gel strength, product texture and consumer acceptance of catfish sausage (Clarias sp.), As well as the resulting moisture and protein content. The best gelatin concentration was produced by the addition of gelatin of 1.5%. Gelatin with a concentration of 1.5% produces the best gel strength with the characteristics of a compact and not too hard gel, has a water content of 68.82% and has a protein content of 16.95%.
Microbial Diversity of Biological Filters in Recirculating Aquaculture Systems for Sand Lobster (Panulirus homarus) Rearing
Authors: Prastowo B W , Penataseputro T
Published: December 2023

The recirculating aquaculture system (RAS) is a technology that reuses water (often less than 5%) in land-based production for farming aquatic organisms’ water treatment. This technology uses filters, either mechanical or biological, for any aquaculture species rearing. In lobster rearing using RAS, one of the most important factors is the quality of rearing water, which depends primarily on the biochemical activities of the microbial communities in the biofilter. There is a significant correlation between the abundance of nitrifying microbial communities and high total ammonia nitrogen (TAN) removal rate. These organisms can convert ammonia accumulates in the system into nitrate. The application of molecular tools (Metagenome 16S Full-Length Barcoding using Oxford Nanopore Platform) to characterize microbial community diversity has been conducted for this study. The diversity of microbes in RAS biofilter for sand lobster rearing is summarized as follows: Nitrification Bacteria group (β-Proteobacteria, g-Proteobacteria, Nitrospirae); Denitrification/Nitrate Reducing Bacteria (α-Proteobacteria, δ-Proteobacteria, Bacteroidetes/Chlorobi, Firmicutes), Sulfide Oxidation Bacteria (ε-Proteobacteria), Probiotic Bacteria (Bacillus subtilis, Pseudomonas sp., Roseobacter sp.). This study’s results indicate a potential for RAS in sand lobster-intensive aquaculture applications and also discuss future studies’ directions.
Analysis on intensive program of vaname shrimp (Litopenaeus vannamei) enlargement in the technical implementation unit of brackish and sea water cultivation (UPT BAPL) Bangil, Pasuruan Regency, East Java
Authors: Marista M , Khatami R M , Santoso J C , Fauzi M H , Samara S H
Published: December 2023

Vannamei shrimp (L. vannamei) is one of the popular aquaculture commodities in Indonesia. This is because vaname shrimp has various advantages compared to other species, such as fast growth rate, can be cultivated with high stocking density, tolerant of high salinity ranges, relatively uniform harvest size, and easy to cultivate. Vannamei shrimp also has many benefits. For example, its meat can be processed as nuggets or food and the shell can be used for medical, cosmetic and even biotechnology. This study aims to determine the production of vaname shrimp at UPT Bangil, one of the largest shrimp productions in East Java. The results of this study showed that the average daily gain of vaname shrimp at UPT Bangil had a yield of 0.33 g/day, and the weight of each shrimp increased to 15.7 g/head. Vannamei shrimp could be harvested at DOC 83 and yields 193.5 kg, with a size of 58. This shows good performance of vaname shrimp enlargement in UPT Bangil.
Simple additive weighting – a recommended seeds selections system for nile tilapia fish farmer
Authors: Hatta H R , Wijayanti A , Septiarini A , Puspitasari N , Wati M
Published: December 2023

Nile tilapias are known to be an economically important farmed fish in Indonesia. Due to its adaptability, this tilapia fish can thrive in various aquatic conditions, making them an important commercial fish to produce locally or export internationally. Because of this potential, this study aims to provide recommendations using the decision support system to facilitate fish farmer decision-making with the Simple Additive Weighting model. This approach is expected to provide recommendations to fish farmers, or the general public interested in having their own Nile tilapia brood stock. The fish in this research was selected randomly following six criteria, namely fish weight, length, movement, fin or body deformation, fish colour and fish stomach condition. The result-based decision making model in this study provides an accuracy of 86.6%.
Nutrients retention function indications in the water quality of the floodplain area on the lower Batanghari River
Authors: Ajie G S , Toruan R L , Yustiawati
Published: December 2023

The Lower Batanghari River often experiences mass deaths of fish. This could be a symptom of eutrophication caused by nutrient enrichment in the water bodies. Floodplain areas are important in reducing parts of these nutrient loadings. This study aimed to examine water qualities related to the nutrient retention function within the Batanghari River floodplain ecosystem. A sampling expedition was conducted in April-May 2021, during a dry season transition period. Sampling was conducted at 20 sampling points stretching over +200 km long within the river and its tributaries. These sampling points were categorized as main river channels, tributaries, and floodplain swamps and lakes. The water quality parameters measured were temperature, pH, conductivity, dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), and total organic matter (TOM). The main river TP concentrations ranged from 0.21-0.33 mg/L, suitable for fishery activities. The overall sampling point groups have distinct characteristics regarding their DO, TP, and TOM values. The average TP in floodplain lakes was found significantly lower (t(13)=8.636, p<0.05) than in the river. Meanwhile, a decrease in TN up to 90% was also found in its lower main river channel. These lower nutrient concentrations along the river floodplain gradients indicate a nutrient retention function. Thus, to reduce eutrophication impacts, floodplain conservation is becoming important.
Morphology and cytochrome b gene identification of Cempedik fish for ascertainment of domestication broodstock source in Belitung Island
Authors: Kurniawan A , Syarif A F , Kurniawan A
Published: December 2023

Cempedik, a native fish of Belitung Island, has economic potential due to its dependence on natural supplies in local rivers. Domestication efforts are needed for this species to continue its availability and protect the sustainibility of its natural population. However, there is little information regarding this freshwater fish belonging to Osteochilus spilurus and the emergence of phenotypic variations in fish with the same local name from different rivers. This study identified morphology and cytochrome b genes from Cempedik fish obtained from Gantung, East Belitung and Membalong, West Belitung. The fin membranes of fish from West Belitung are reddish in color, while the color is brownish gray in fish from East Belitung. Meristic variation is found in scales on lateral line. Fish from both locations were in different clusters in the phylogenetic tree construction with large genetic distances. It is possible that there are cryptic conditions or species differences in the two fish samples.
Antibacterial activity of gel hand sanitizer from seaweed extract (Kappaphycus alvarezii)
Authors: Putri W K , Pujiastuti D Y , Saputra E
Published: December 2023

Seaweed extract (Kappaphycus alvarezii) contains flavonoids, triterpenoids, steroids, and alkaloids which have antibacterial activity. The purpose of this study was to determine the potential of seaweed extract (K. alvarezii) as a hand sanitizer product and to determine the antibacterial activity of hand sanitizer gel from seaweed extract (K. alvarezii) against S. aureus and E. coli bacteria. This research was conducted by experimental methods Inhibitory Zone Test, Homogeneity Test, Viscosity Test, pH Test, Spreadability Diameter Test, Organoleptic Test and Skin Irritation Test. This study used a completely randomized design (CRD). The data obtained were then analyzed using the ANOVA method and if there was a difference, then the significant difference test was continued using the Duncan Multiple Range Test (DMRT) at a significance level of 5% (α=0.05). The results of this study showed that the seaweed extract of K. alvarezii gave good results. The appearance of the hand sanitizer gel in each treatment is homogeneous. The value of gel viscosity is close to standard. The hand sanitizer gel has a pH of 5. The diameter of the spread has a result of 5-6. Does not cause irritation to the skin. Has a zone of inhibition that is classified as strong-very strong.
Effect of laser shock peening as a pretreatment on ion nitriding of precipitation hardened stainless steel
Authors: S Avinash , Yadav Vineet Kumar , Duraiselvam Muthukannan
Published: December 2023

Laser shock peening (LSP) is emerging as an advanced technology to improve the fatigue life of engineering products. Also, this can improve wear and corrosion resistance as add-on benefits to the properties of the materials. In the present investigation, a systematic understanding of the hybrid surface treatment that combines LSP with ion nitriding, also known as plasma nitriding (PN) of precipitated hardened (PH) stainless steel was conducted to improve the effective case hardening layer. The effect of input parameters such as laser spot diameter, the number of superimposed layers, and overlap rate was investigated on the performance characteristics, which include surface morphology, microhardness, and the change in microstructure after the proposed treatment. The surface characterization results reveal that an 80% laser overlap rate modified the surface roughness of PN samples owing to higher surface roughness values induced by ablation during the LSP treatment. The microhardness and optical microscopy (OM) results revealed an increase in the effective hardening layer thickness of about 115% for a 40% overlap rate owing to the absence of blind spots. In addition, XRD analysis revealed the presence of Fe4N and CrN compounds on the surface of the PN samples. Scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) elemental mapping reveals the presence of a nitrogen-rich phase in the effective hardened layer and increased effective hardened layer thickness owing to grain refinement of LSP pre-processing.
Phonons from density-functional perturbation theory using the all-electron full-potential linearized augmented plane-wave method FLEUR
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Authors: Gerhorst Christian-Roman , Neukirchen Alexander , Klüppelberg Daniel A , Bihlmayer Gustav , Betzinger Markus , Michalicek Gregor , Wortmann Daniel , Blügel Stefan
Published: December 2023

Phonons are quantized vibrations of a crystal lattice that play a crucial role in understanding many properties of solids. Density functional theory provides a state-of-the-art computational approach to lattice vibrations from first-principles. We present a successful software implementation for calculating phonons in the harmonic approximation, employing density-functional perturbation theory within the framework of the full-potential linearized augmented plane-wave method as implemented in the electronic structure package FLEUR. The implementation, which involves the Sternheimer equation for the linear response of the wave function, charge density, and potential with respect to infinitesimal atomic displacements, as well as the setup of the dynamical matrix, is presented and the specifics due to the muffin-tin sphere centered linearized augmented plane-wave basis-set and the all-electron nature are discussed. As a test, we calculate the phonon dispersion of several solids including an insulator, a semiconductor as well as several metals. The latter are comprised of magnetic, simple, and transition metals. The results are validated on the basis of phonon dispersions calculated using the finite displacement approach in conjunction with the FLEUR code and the phonopy package, as well as by some experimental results. An excellent agreement is obtained.
Better soon than never: climate change induces strong phenological reassembly in the flowering of a Mediterranean shrub community
Authors: Pareja-Bonilla Daniel , Arista Montserrat , Morellato Leonor Patrícia Cerdeira , Ortiz Pedro Luis
Published: December 2023

Background and Aims

Flowering is a key process in the life cycle of a plant. Climate change is shifting flowering phenologies in the Northern Hemisphere, but studies with long data series at the community level are scarce, especially those considering the consequences of phenological changes for emerging ecological interactions. In the Mediterranean region, the effects of climate change are stronger than the global average and there is an urgent need to understand how biodiversity will be affected in this area.

Methods

In this study, we investigated how the entire flowering phenology of a community comprising 51 perennial species from the south of the Iberian Peninsula changed from the decade of the 1980s to the 2020s. Furthermore, we have analysed the consequences of these changes for flowering order and co-flowering patterns.

Key Results

We have found that the flowering phenology of the community has advanced by ~20 days, which is coherent with the increasing temperatures related to climate change. Individual species have generally advanced their entire flowering phenology (start and end) and increased their flowering duration. The early flowering has resulted in a re-organization of the flowering order of the community and generated new co-flowering assemblages of species, with a slight trend towards an increase of shared flowering time among species.

Conclusions

The advanced flowering phenology and changes in flowering duration reported here were of unprecedented magnitude, showcasing the extreme effects of climate change on Mediterranean ecosystems. Furthermore, the effects were not similar among species, which could be attributed to differences in sensitivities of environmental cues for flowering. One consequence of these changes in flowering times is ecological mismatches, indicated by changes in the flowering order and co-flowering between decades. This new scenario might lead to new competitive or facilitative interactions and to the loss or gain of pollinators.
Pleistocene climatic oscillations influenced the emergence of geographically widespread and restricted genetic lineages in an Andean grasshopper species group
Authors: Guzmán Noelia V , Gandini Luciano M , Castillo Elio R , Fernandez Campón Florencia , Cigliano Maria Marta , Confalonieri Viviana A
Published: December 2023

The grasshopper Trimerotropis pallidipennis species complex is distributed across arid and semi-arid environments from North to South America, reaching high altitudes along the Andes Mountain range. Currently, there are four valid species of Trimerotropis in South America. However, some species were found to comprise several genetic lineages. Here, we describe the genetic structure, lineage diversification, and environmental requirements within the Trimerotropis species complex in South America based on sequences from the mitochondrial COI gene, 4048 single nucleotide polymorphisms, and ecological niche modelling. The analyses revealed the existence of at least five lineages: two with a restricted geographical distribution and three with a very wide one. The results provide evidence that glacial cycles promoted not only the presence of refuge areas but also the isolation of widely distributed lineages on the eastern and western sides of the southern Andes, potentially driving the emergence of the Trimerotropis sp. lineage, which can tolerate more temperate habitats. Our results provide evidence for the effects of Pleistocene climatic changes on the diversification history of a South American grasshopper species complex.
How Do Child Welfare Social Workers Assess the Leadership of Their First-line Managers? A 15-Year Perspective
Authors: Norrgård Amanda , Tham Pia , Strömberg Annika , Kåreholt Ingemar
Published: December 2023

The study aimed to investigate how child welfare social workers assessed the leadership of their first-line managers over a period of fifteen years and to examine whether the assessments have changed over time. More specifically, the analysis focused on the extent to which social workers perceive the leadership of their first-line managers to be empowering, supportive and fair. Data were collected in the years 2003 (n = 293), 2014 (n = 300) and 2018 (n = 309) using the same questionnaire, mainly based on QPS Nordic, which was distributed to social workers working with investigations of children and youth. The results show that the social workers assessed all measured aspects of their first-line managers’ leadership as better in 2014 compared to 2003 and significantly better in 2018 compared to 2003. In light of previous studies showing that child welfare managers experience less optimal conditions for their leadership, the results are surprising. How is it possible that the first-line managers, despite their own descriptions of a more difficult leadership situation, are seen as more supportive, empowering and fair in their leadership from the social workers’ perspective? Possible explanations for the social workers’ better assessments over the years, such as specialisation, are discussed.
Alpha/beta oscillations reveal cognitive and affective brain states associated with role taking in a dyadic cooperative game
Authors: Flösch Karl-Philipp , Flaisch Tobias , Imhof Martin A , Schupp Harald T
Published: December 2023

Social cooperation often requires taking different roles in order to reach a shared goal. By defining individual tasks, these roles dictate processing demands of the collaborators. The main aim of the present study was to examine the hypothesis that induced alpha and lower beta oscillations provide insights into affective and cognitive brain states during social cooperation. Toward this end, an experimental game was used in which participants had to navigate a Pacman figure through a maze by sending and receiving information about the correct moving direction. Supporting our hypotheses, individual roles taken by the collaborators during gameplay were associated with significant changes in alpha and lower beta power. Furthermore, effects were similar when participants played the Pacman Game with human or computer partners. Findings are discussed from the perspective of the information-via-desynchronization hypothesis proposing that alpha and lower beta power decreases reflect states of enhanced cortical information representation. Overall, experimental games are a useful tool for extending basic research on brain oscillations to the domain of naturalistic social interaction as emphasized by the second-person neuroscience perspective.