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Copyright of Indonesian Fisheries Processing Journal / Jurnal Pengolahan Hasil Perikanan Indonesia is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examines the use of edible coatings from liquid smoke and chitosan as natural preservatives to extend the shelf life of sausages. Liquid smoke was obtained from the pyrolysis of young coconut shells at 300°C (A1), 340°C (A2), 380°C (A3), and 420°C (A4), which were then purified by distillation to remove tar and other harmful compounds. The resulting liquid smoke was then used to dissolve the chitosan (1-2% w/w) to form an edible coating to be applied to the sausages. The ability of the edible coating to preserve sausage was analyzed using the total plate count (TPC), total volatile base nitrogen (TVB-N), and organoleptic tests. The results of the organoleptic and antibacterial tests were statistically analyzed using the least significant difference (LSD) on SPSS v22. The results showed that different pyrolysis temperatures in liquid smoke preparation affected the properties of edible coatings, which, in turn, affected the endurance of sausage samples. The resulting edible coating maintained the freshness of sausages for up to 100 hours in the TVB-N test and 96 hours in the TPC test. The results of the organoleptic test revealed that the edible coating prolonged the sausage aroma and texture for up to 88 hours, which was achieved by the sample with A4 liquid smoke and a 2% chitosan concentration. [ABSTRACT FROM AUTHOR]

Liquid smoke is produced by the pyrolysis of biomass. The use of liquid smoke has numerous advantages over traditional smoking methods. The liquid smoke market is well-established and growing, providing an opportunity to commercialize biomass pyrolysis. This study aimed to investigate the utility of durian rind, biomass waste rich in lignin, cellulose, and hemicellulose, as a natural preservative to extend the shelf life of chicken meatballs and to mitigate environmental problems caused by the disposal of untreated durian rind waste. Dried durian rinds with approximately 10% water content were pyrolyzed at temperatures of 300°C (T1 liquid smoke), 340°C (T2 liquid smoke), and 380°C (T3 liquid smoke) using a slow pyrolysis reactor in batch conditions to produce crude liquid smoke, which was then purified by distillation at 190°C. Chicken meatballs were then soaked in liquid smoke solutions with concentrations of 1%, 2%, and 3% for 15 minutes, and the meatballs checked for signs of spoilage every 4 hours. Tests for total volatile base nitrogen (TVB-N), in addition to the total plate count (TPC) and most probable number (MPN) of Escherichia coli bacteria, were performed to evaluate the preservation ability of the liquid smoke. The results indicated that both the pyrolysis temperature and liquid smoke concentration affected the preservation time, with a pyrolysis temperature of T3 and liquid smoke concentration of 3% optimum for chicken meatball preservation. Under these conditions, the meatballs could be stored for 56 hours with TVB-N, TPC, and E. coli MPN values of 21.01 mg N/100 g, 5.37 × 104 CFU/g, and 75 MPN/g, respectively. The findings suggest that liquid smoke derived from durian rinds could be used to preserve chicken meatballs.

Joruk is a fermented fish product typical from East Ogan Komering Ulu, South Sumatra. This study aims to determine the chemical, microbiological, and sensory properties of the joruk during fermentation, as well as to get the right fermentation time for joruk production. Research was performed by preparing joruk using wader fish. Observations included pH, total lactic acid, water content, and total volatile base (TVB), total molds and yeasts, total microbes, and total lactic acid bacteria (LAB). Furthermore, the best treatment was observed for sensory properties and protein content. Results showed that during fermentation there was a decrease in the pH value, total mold, total microbes, and water content, while the total amount of lactic acid, LAB, and TVB increased. The best treatment was obtained on joruk stored on the 10th day of fermentation with a pH value of 6.33, total lactic acid 9.48%, water content 67.74%, TVB 93.88%, and total LAB, total mold/yeast, and total microbes was respectively 10.46, 7.21, and 12,13 log CFU/g. Sensory properties for raw joruk was brown with 6.2 scale, fishy (6.4), and intact appearance (5.1). Sensory properties for cooked joruk was brown (4.2), fishy (6.7), salty taste (3.1), sour taste (8.4), and incomplete appearance (2.8).

Smoke powder is a natural alternative to artificial preservatives for extending the shelf life of food products. This study assessed the use of smoke powder derived from durian rinds as a preservative for chicken meatballs. Durian rinds were pyrolyzed at 300 °C (T1), 340 °C (T2), and 380 °C (T3) to produce liquid smoke. After filtration to separate the remaining carbon, the resulting liquid smoke was purified by distillation at 190 °C and then converted into a smoke powder through the addition of maltodextrin and spray drying. The feasibility of smoke powder as a preservative for chicken meatballs was tested using total volatile base (TVB), total plate count (TPC), pH, and most probable number (MPN) tests for Escherichia coli. The findings demonstrated an upward trend in TVB, TPC, and MPN values over the storage duration. The TVB and TPC tests revealed that meatballs preserved with T3 smoke powder retained acceptable quality upon 64 h of storage. The MPN value of the T3 sample showed that E. coli bacterial contamination could still be tolerated up to 68 h of storage.

Ikan baronang hidup di perairan mangrove hingga terumbu karang dengan kedalaman mencapai 6 meter. Biasanya ikan baronang dijual dalam kondisi yang segar. Teknik penanganan ikan yang paling umum dilakukan untuk menjaga kesegaran ikan adalah penggunaan suhu rendah. Penelitian ini bertujuan untuk menentukan kemunduran mutu ikan baronang dari Kepulauan Seribu yang disimpan dengan menggunakan es. Perbandingan ikan dan es yang dipergunakan adalah 1:1 (b/b). Penentuan kesegaran ikan baronang pada penelitian ini dilakukan berdasarkan pengujian pH, TVB, dan TPC. Pengamatan dilakukan setiap 24 jam sekali selama 3 hari. Nilai pH mengalami penurunan yang tidak signifikan pada penyimpanan hari ke-2 dan hari ke-3. Nilai TVB ikan baronang pada hari pertama yaitu 10,57 mg N/100 g. Nilai tersebut menunjukkan ikan pada awal penyimpanan masih dalam keadaan segar. Jumlah total mikroba setelah penyimpanan 3 hari mengalami peningkatan menjadi 7,48 log CFU/g. Ikan baronang setelah penyimpanan 3 hari masih layak untuk dikonsumsi berdasarkan nilai pH dan TVB.

This article critically evaluates legal developments in relation to the regulation of abuse of dominance in the Hong Kong television sector, focusing on the milestone case of Television Broadcasts Ltd (TVB). The TVB case was decided under the previous sectoral competition regime under the Broadcasting Ordinance (BO) and has since 2015 been replaced by the crosssector Competition Ordinance (CO). Nevertheless, the decisions of the Communications Authority (CA) and the Court of First Instance (CFI) in 2013 and 2016 respectively provided important insights on the application of the small but significant and non-transitory decrease in quality (SSNDQ) test in two-sided markets and the 'purpose/object' and 'effect' tests to exclusivity practices, and more generally, the analysis of abuse of buyer power in a labour market setting. Hong Kong competition authorities are likely to be confronted with similar issues as they gradually expand their enforcement activities into digital markets and abuse of market power scenarios beyond the broadcasting sector. The purpose of this article is to subject the TVB decisions, in respect of their analysis of market definition, market power, the abusive conduct, and the remedial aspect, to in-depth critique. It situates the issues in the broader context of the crosssector CO under which future cases of abuse of dominance in Hong Kong will be scrutinized. [ABSTRACT FROM AUTHOR]

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base nitrogen (TVB-N) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB-N values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base nitrogen (TVB-N) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB-N values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base nitrogen (TVB-N) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB-N values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base nitrogen (TVB-N) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB-N values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base nitrogen (TVB-N) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB-N values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base (TVB) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2–3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours.

Oil palm kernel shell is a waste product of palm oil manufacturing and contains significant amounts of several chemical compounds including cellulose, hemicelluloses, and lignin. Pyrolysis of these compounds results in good quality liquid smoke. The aim of this research was to utilize this liquid smoke to preserve mackerel. The liquid smoke in this research was obtained by pyrolyzing oil palm kernel shell at temperatures ranging from 300-380°C. The resulting liquid smoke was then distilled at 200°C, and its chemical composition was analyzed using gas chromatography-mass spectrometry. The liquid smoke was then used to preserve mackerel at a variety of concentrations, including 0.5%, 1%, 2%, and 3%. The efficacy of preserving the mackerel using liquid smoke was assessed through TVB (total volatile base) analysis and organoleptic testing. TVB testing showed that mackerel remained fresh for up to 64 hours after being treated with 2% and 3% liquid smoke at a pyrolysis temperature of 380°C, with TVB values of 26.733 mgN and 24.974 mgN, respectively. The organoleptic testing showed that at a liquid smoke concentration of 3% and a pyrolysis temperature of 380°C, mackerel can remain fresh for up to 48 hours, with acceptable color and texture, and is suitable for consumption. Meanwhile, the non-preserved (control) mackerel had already deteriorated within 24 hours in terms of color, texture, and smell. [ABSTRACT FROM AUTHOR]

Smoke powder is a natural alternative to artificial preservatives for extending the shelf life of food products. This study assessed the use of smoke powder derived from durian rinds as a preservative for chicken meatballs. Durian rinds were pyrolyzed at 300 °C (T1), 340 °C (T2), and 380 °C (T3) to produce liquid smoke. After filtration to separate the remaining carbon, the resulting liquid smoke was purified by distillation at 190 °C and then converted into a smoke powder through the addition of maltodextrin and spray drying. The feasibility of smoke powder as a preservative for chicken meatballs was tested using total volatile base (TVB), total plate count (TPC), pH, and most probable number (MPN) tests for Escherichia coli . The findings demonstrated an upward trend in TVB, TPC, and MPN values over the storage duration. The TVB and TPC tests revealed that meatballs preserved with T3 smoke powder retained acceptable quality upon 64 h of storage. The MPN value of the T3 sample showed that E. coli bacterial contamination could still be tolerated up to 68 h of storage., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The increase in production of warm water fishes in Iran, such as carp, produces a need for development of new methods of food production for human consumption. In this research four formula for production of fish cake from carp were investigated. Using the chosen formula which consisted of 52% debonded carp meat, 28% potato, 10% whole egg, 8% flour and 2% of a mixture of garlic, ginger, nutmeg, pepper powder and salt, the fish cake was made. Then during 120 days at 18°C, according to a time schedule, the samples were tested for changes in their total volatile base, peroxide value and total count of bacteria. The results indicate that changes in TVB was from 14.0 to 18.9 mg/100g, peroxide value changed from 4.0 to 4.9 meq/kg. The total count of bacteria for all of the samples was negative. The shelf life of carp cake as the result of peroxide value increase was estimated to be 90 days at 18°C in cold store. This carp cake contains 20% protein, 8% oil, 10% carbohydrate, 6% ash and 56% moisture.

This article discusses why and how, in October 2013, the struggle for a free-to-air TV license by HKTV could turn into a social movement. It traces the historical makeup of neo-liberalization and monopolization in TV production: TV licensing as a (colonial) governmental measure on the media under the guise of a “laissez-faire” media policy, which has been reinvented as a grip on cultural rights to TV in post-handover Hong Kong. HKTV's “David vs Goliath” struggle against the decision demonstrated how political fear (of Beijing control over the Hong Kong government) among the people has fed into an anxiety over media monopoly. What might have caught the powers-to-be by surprise was the vociferous protest from the general public. My analysis situates the incident in the context of an array of travesties against media freedoms in recent years, which have enabled the audience (as citizens) to rise up and demand their cultural rights to creative and quality TV. I conclude by examining the agency of creativity, which, in this case, has been articulated to an agency of (decolonized) identity in the struggle for democracy in the present political cultural conjuncture of Hong Kong. [ABSTRACT FROM AUTHOR]

• Developed a large scale brain network model that includes three novel networks. • Proposed models can generate patterns with high-frequency oscillations (94–144 Hz). • The results indicate that changing the model parameters can modify its behaviours. • The generated EEG abnormal patterns are compared with known epileptic EEG patterns. Unlike normal EEG patterns, the epileptiform abnormal pattern is characterized by different morphologies such as the high-frequency oscillations (HFOs) of ripples on spikes, spikes and waves, continuous and sporadic spikes, and ploy2 spikes. Several studies have reported that HFOs can be novel biomarkers in human epilepsy study. To regenerate and investigate these patterns, we have proposed three large scale brain network models (BNM S) by linking the neural mass model (NMM) of Stefanescu-Jirsa 2D (S-J 2D) with our own structural connectivity derived from the realistic biological data, so called, large-scale connectivity connectome. These models include multiple network connectivity of brain regions at different lobes from both hemispheres (left and right). The network nodes of these models were simulated based on the local dynamics of the S-J 2D model, which were generated by adjusting the global coupling between the excitatory and inhibitory populations. The connection strength between the inhibitory and excitatory neurons of the local model was also adjusted to investigate different morphology patterns. The proposed network models were developed and evaluated by simulations. Different abnormal patterns of EEG brain activities such as HFO S ripples on spikes, spikes, continuous spikes, sporadic spikes and ploy2 spikes ranging from 94 to 144 Hz were regenerated. Different morphology patterns of abnormality were generated from novel BNMs and the epileptiform abnormal pattern obtained in actual EEG and other computational models were also compared. This study is able to assist researchers and clinical doctors in the field of epilepsy to better understand the complex neural mechanisms behind the abnormal oscillatory activities, which may lead to the discovery of new clinical interventions in epilepsy. [ABSTRACT FROM AUTHOR]

Trimethylamine (TMA) is formed in ice-stored fish from the reduction of trimethylamine oxide (TMAO) by bacteria predominately of the genus Shewanella. In fish harvested from warm waters spoilage is predominately due to bacteria of the genus Pseudomonas and ammonia rather than TMA is produced. TMA concentrations in the flesh of ice-stored fish increases exponentially during storage, perhaps following a dwell period of a few days. The kinetics of the formation of TMA was determined by fitting published data for a large number of species to an exponential mathematical model. The results show a marked difference in kinetics between fish harvested from the wild and fish harvested from aquaculture. The increase in ammonia during spoilage of fish from cold waters is small compared with that from TMA, and the increase in Total Volatile bases (TVB) during storage is mostly due to the production of TMA. Many sets of data on TVB formation during spoilage show the effects of leaching. The variances of TMA and TVB measurements are large, and additionally there are variances between batches due to biological factors. Neither TMA nor TVB are effective indices of spoilage in either commercial quality control, or in official regulatory control. [ABSTRACT FROM AUTHOR]

The large literature on the formation of volatile amines, and of their aggregation as Total Volatile Base (TVB), during spoilage of vertebrate, teleostean fish in ice, and their used as indices of freshness is critically reviewed. This part reviews analytical procedures. The thermodynamics of the distillation process in determining TVB is reviewed and optimum conditions for the distillation are considered. Distillation other than at temperatures below about 50°C is accompanied by decomposition of nitrogen-containing compounds with the formation of ammonia additional to the intrinsic ammonia in the sample. The amount of decomposition differs among the various procedures used for determining TVB. Rapid distillation in automated distillation units produces the smallest amount of decomposition. Trimethylamine (TMA) is often determined by the picrate method, but this is not completely specific for TMA and some dimethylamine is included in the result depending of the alkali and the amount of formaldehyde used. Other analytical techniques such as GLC and Flow Injection Analysis are specific and are to be preferred for critical work. There are differences among procedures for determining TVB and TMA in the way concentrations in the sample are calculated when using protein-free extracts which leads to biases between methods. [ABSTRACT FROM AUTHOR]

Abstract: For solving hyperbolic systems with stiff sources or relaxation terms, time stepping methods should combine favorable monotonicity properties for shocks and steep solution gradients with good stability properties for stiff terms. In this paper we consider implicit–explicit (IMEX) multistep methods. Suitable methods will be constructed, based on explicit methods with general monotonicity and boundedness properties for hyperbolic equations. Numerical comparisons are made with several implicit–explicit Runge–Kutta methods. [Copyright &y& Elsevier]

Abstract: We consider linear multistep methods that possess general monotonicity and boundedness properties. Strict monotonicity, in terms of arbitrary starting values for the multistep schemes, is only valid for a small class of methods, under very stringent step size restrictions. This makes them uncompetitive with the strong-stability-preserving (SSP) Runge–Kutta methods. By relaxing these strict monotonicity requirements a larger class of methods can be considered, including many methods of practical interest. In this paper we construct linear multistep methods of high-order (up to six) that possess relaxed monotonicity or boundedness properties with optimal step size conditions. Numerical experiments show that the new schemes perform much better than the classical monotonicity-preserving multistep schemes. Moreover there is a substantial gain in efficiency compared to recently constructed SSP Runge–Kutta (SSPRK) methods. [Copyright &y& Elsevier]

The chicken TVBS1 protein serves as the cellular receptor for the cytopathic subgroups B and D avian sarcoma and leukosis viruses (ASLVs) as well as for the non-cytopathic subgroup E ASLV. Previous studies had mapped the subgroup B viral interaction determinants to a region that was located between residues 32 and 46 of TVBS1 [J. Virol. 76 (2002) 5404]. To gain a greater insight into ASLV Env–receptor interactions and the possible role of these interactions in viral cytopathic effects, we employed a homolog-scanning mutagenesis approach to identify amino acid residues important for subgroup E viral receptor function by exchanging amino acid residues between TVBS1 and its human homolog, DR5. These studies identified residues Tyr-67, Asn-72, and Asp-73 of TVBS1 as important subgroup E viral interaction determinants. Intriguingly, these three residues are conserved between TVBS1 and DR5, demonstrating that the human protein contains critical subgroup E viral interaction determinants, but in this context, they cannot support viral entry. These data confirm that the molecular determinants of the TVB receptor required for subgroup E viral entry are completely distinct from those used by subgroup B viruses. [Copyright &y& Elsevier]

The influence of emersion and storage temperature (5, 10, and 20°C) on survival and metabolism of non-protein nitrogenous compounds of wild harvest clams, Tapes decussatus, were assessed under laboratory conditions. The clams showed a temperature dependence of emersion tolerance with the highest survival at 10°C (LT50 = 16 d) and the least survival at 20°C (LT50 = 5 d). Ammonia and trimethylamine (TMA) levels in the mantle cavity fluids of emersed clams, at all temperatures, increased exponentially (r2 > 0.8 in all cases) which implies a steep rise in the production of these nitrogenous compounds following an extended period of emersion (> 5 d in all cases). Tissue levels of TMA and total volatile bases (TVB) in the live clams showed a similar pattern of increase as a function of emersion duration and attained final values comparable to those which, on the basis of sensory analysis, would indicate that fish fillets were spoiled (> 12 mg TMA per 100 g tissue). Concomitantly, tissue trimethylamine oxide (TMAO) levels declined to undetectable values. At 10°C and 20°C, the mantle cavity fluid ammonia and TMA levels showed a strong correlation with tissue TVB and TMA concentrations (r = 0.91 and 0.92, respectively). It is suggested that, in such cases, mantle cavity fluid TVB/TMA analyses form practical, non-destructive quality criterion for live-marketed clam. [ABSTRACT FROM AUTHOR]

A capillary electrophoretic method with indirect UV detection is described for simultaneous determination of ammonia, dimethylamine (DMA), trimethylamine (TMA) and trimethylamine-n-oxide (TMAO) in aqueous extracts of fish. A buffer consisting of 4 mM formic acid, 5 mM copper(II)sulfate and 3 mM crown ether 18-crown-6 enabled separation of the analytes in 5–10 min. The use of an extended light path capillary technique resulted in a good sensitivity and repeatability. The linear dynamic range, based on a hydrostatic injection at 50 mbar for 2 s, was from the detection limit to at least 2.5 mM. The detection limit for ammonia, DMA, TMA, and TMAO was less than 0.04 mM, corresponding to 2 mg nitrogen per 100 g fish. As an extra benefit, the method also provided a quantitative determination of potassium, sodium, calcium and magnesium ions. [Copyright &y& Elsevier]

TVB is an avian death domain-containing receptor belonging to the TNF receptor family and is proposed to be the ortholog to mammalian DR5. Although TVB receptor activation has been demonstrated to mediate apoptosis in chick embryo fibroblasts, there is essentially no information regarding TVB expression or regulation in the mature hen ovary, and in particular within the follicle granulosa layer where apoptosis is known to promote atresia. Significantly, the TVB receptor represents the fourth death domain-containing receptor (also including Fas, TNF-R1, and DR6) found to be expressed within hen granulosa cells. Levels of TVB expression are higher in prehierarchal follicles actively undergoing atresia compared to healthy follicles. However, increased TVB expression does not precede follicle death induced in vitro. Furthermore, TVB expression within granulosa cells is highest during the final stages of follicle development when follicles are not normally susceptible to undergoing atresia. These results provide evidence that TVB receptor signaling in the ovary may function in a capacity other than solely to mediate granulosa cell death and follicle atresia. [Copyright &y& Elsevier]

This paper describes numerical experiments of high resolution schemes applied to open-channel flow equations with discontinuities in the solution. The high resolution schemes tested are the second-order symmetric TVD scheme, the upwind TVD scheme, the upwind TVB scheme, the predictor-corrector TVD scheme, the second- and third-order ENO schemes, and the space time conservation method. The six schemes except the space time conservation method are the approximate Riemann solvers, so that they need entropy correction for the numerical solution of physical meaning. These methods are applied to 1D dam-break wave propagation over the horizontal and frictionless open-channel. The computed solutions are compared with the Stoker's solution and the solution from the first-order Roe's scheme. All schemes including the Roe's scheme are found to yield results which agree well with the analytical solution when the ratio of upstream to downstream depths is moderate such as 0.05. When the ratio is reduced to 0.0001, most schemes appear to be diffusive and to retard the shock front. It was found that the second-order upwind TVB scheme and the space time conservation scheme are very accurate but expensive regarding the computing time. The second-order ENO scheme and the second-order predictor-corrector TVD scheme appear to be moderately accurate and economical. [ABSTRACT FROM AUTHOR]

Background: Durian peel is a type of biomass waste that contains cellulose, hemicelluloses, and lignin. The pyrolysis of these compounds results in production of liquid smoke which can be used as a natural preservative to replace current synthetic preservatives. This research assessed the ability of liquid smoke produced during pyrolysis of durian peel to preserve fish. Methods: Dry durian peel waste underwent batch reactor pyrolysis at 340°C and 380°C, resulting in production of liquid smoke (grade 3), charcoal, and tar. This liquid smoke was then distilled at 190°C to produce grade 1 liquid smoke, which was used to preserve mackerel. The preservation process was conducted by soaking the mackerel samples in liquid smoke at 0.5, 1, 2, and 3% concentration levels followed by observations every 6 hours. Tests to determine the total volatile base (TVB) content, antibacterial quality of the liquid smoke and organoleptic quality of the fish were conducted in order to assess the preservation properties of the liquid smoke. Results: Tests on the antibacterial effects showed that the liquid smoke inhibited the growth of Escherichia coli and Staphylococcus aureus on fish even at low concentrations. At 54 hours, the TVB values remained below 30 mg nitrogen/g, indicating that the fish was still safe for human consumption. Results from the organoleptic tests showed that the concentration of liquid smoke influenced the preservation effects. Conclusions: At a concentration of 2-3%, the fish samples possessed acceptable flavor, taste, color and texture for up to 48 hours of soaking. However, the best conditions were obtained with a 3% concentration of liquid smoke (produced with 340°C pyrolysis), as the fish was still considered acceptable for up to 42 hours., Competing Interests: No competing interests were disclosed., (Copyright: © 2019 Faisal M et al.)