Nutrient digestibility in black soldier fly larva was greater than in adults for pigs and could be estimated using fiber.

The objectives of the present study were to determine the nutrient digestibility of fish meal, defatted black soldier fly larvae (BSFL), and adult flies and to develop equations for estimating in vitro nutrient digestibility of BSFL for pigs. in vitro digestion procedures were employed to mimic the digestion and absorption of nutrients in the pig intestine. Correlation coefficients between chemical composition and in vitro nutrient digestibility of BSFL were calculated. In Exp. 1, in vitro ileal digestibility (IVID) of dry matter (DM) and crude protein (CP) and in vitro total tract digestibility (IVTTD) of DM and organic matter in defatted BSFL meal were less (p < 0.05) than those in fish meal but were greater (p < 0.05) than those in adult flies. In Exp. 2, CP concentrations in BSFL were negatively correlated with ether extract (r = -0.91) concentration but positively correlated with acid detergent fiber (ADF; r = 0.98) and chitin (r = 0.95) concentrations. ADF and chitin concentrations in BSFL were negatively correlated with IVID of DM (r = -0.98 and -0.88) and IVTTD of DM (r = -1.00 and -0.94) and organic matter (r = -0.99 and -0.98). Prediction equations for in vitro nutrient digestibility of BSFL were developed: IVID of CP (%) = -0.95 × ADF (% DM) + 95 (r2 = 0.75 and p = 0.058) and IVTTD of DM (%) = -2.09 × ADF + 113 (r2 = 0.99 and p < 0.001). The present in vitro experiments suggest that defatted BSFL meal was less digestible than fish meal but was more digestible than adult flies, and nutrient digestibility of BSFL can be predicted using ADF as an independent variable.

Complete genome sequence of an oryctes rhinoceros nudivirus isolated from Korean rhinoceros beetles (Trypoxylus dichotomus) in Korea.

Nudivirus-infected Korean rhinoceros beetles (Trypoxylus dichotomus) were first identified in 2015, and while a complete genome sequence of the virus has long been uploaded to the NCBI database, it has not been examined in detail. Here, we describe the genomic characteristics of Trypoxylus dichotomus nudivirus (TdNV), which represents a new Oryctes rhinoceros nudivirus (OrNV) strain, isolated from infected T. dichotomus in the Republic of Korea. We examined factors derived by the cross-species infection of OrNV from nucleotide levels to the whole genome level. Our genomic analysis study suggests that TdNV-Korea is highly conserved with other OrNVs in terms of genomic structures and genome size. Our investigation of the genomic structure revealed that TdNV-Korea has the least number of open reading frames (ORFs) of all available OrNV genomes; three hypothetical genes were notably absent only in TdNV-Korea. In addition, the genomic alteration of the nudivirus core genes discloses that various amino acid mutations caused by single-nucleotide polymorphism and short indels (insertion/deletion) were found in most of the nudivirus core genes of TdNV-Korea. Our findings provide a valuable resource for those seeking a greater understanding of cross-species nudivirus transmission and will certainly provide valuable insight for reconstruction and reinterpretation of future and previously identified OrNV strains.

Evaluation of subchronic oral dose toxicity and allergen of freeze-dried powder of Locusta migratoria (Orthoptera: Acrididae) as a novel food source.

The migratory locust, Locusta migratoria (Orthoptera: Acrididae), is a well-known edible insect which may serve as new source of human food and animal feed. However, potential toxicity and food safety of L. migratoria had not been investigated extensively until now. Therefore, in this study, we aimed to investigate toxicity of freeze-dried powder of L. migratoria (fdLM) and identify allergic components in ELISA and PCR techniques. In this subchronic study, fdLM was administered once daily by oral gavage at the doses of 750, 1500, and 3000 mg/kg/day. No toxicological changes were observed in both sexes of rats for 13 weeks in accordance with the OECD guidelines and GLP conditions. In addition, fdLM did not induced increases of serum immunoglobulin E and 21 homologous proteins were not detected under our present conditions. In conclusion, the NOAEL (no-observed-adverse-effect level) was 3000 mg/kg/day and no target organ was identified in both sexes. In conclusion, we found that fdLM is safe with no adverse effects and offers the potential of its use as an edible ingredient or other biological uses.

Evaluation of Fermented Oat and Black Soldier Fly Larva as Food Ingredients in Senior Dog Diets.

The aim of this study was to evaluate the suitability of fermented oat (FO) and black soldier fly larva (BSFL) as food ingredients for dogs. A total of 20 spayed female dogs were divided into four treatment groups, with 5 dogs per group. The four treatment groups consisted of a control group, a diet with 10% FO, one with 5% BSFL, and one with 10% FO and 5% BSFL, and each experimental food was fed for 12 weeks. The feeding of FO and/or BSFL did not affect the daily food intake, body weight, body condition score, fecal score, or skin condition of the dogs. In all the experimental groups, no significant differences in serum IgG, IL-10, or TNF-α levels were observed upon the feeding of FO and/or BSFL. Some hematological (white blood cell and basophils) and serum biochemical parameters (phosphorous, globulin, and alkaline phosphatase) showed significant differences with FO and/or BSFL feeding compared to the control group, but they were within the normal reference range. No adverse clinical signs related to these parameters being affected by FO and BSFL were observed. The feeding of BSFL for 12 weeks reduced the serum cholesterol level (p < 0.05) at the end of the experiment. Our findings suggest the suitability of FO and BSFL as food materials for dogs.

Luminance-Degradation Compensation Based on Multistream Self-Attention to Address Thin-Film Transistor-Organic Light Emitting Diode Burn-In.

We propose a deep-learning algorithm that directly compensates for luminance degradation because of the deterioration of organic light-emitting diode (OLED) devices to address the burn-in phenomenon of OLED displays. Conventional compensation circuits are encumbered by high cost of the development and manufacturing processes because of their complexity. However, given that deep-learning algorithms are typically mounted onto systems on chip (SoC), the complexity of the circuit design is reduced, and the circuit can be reused by only relearning the changed characteristics of the new pixel device. The proposed approach comprises deep-feature generation and multistream self-attention, which decipher the importance of the variables, and the correlation between burn-in-related variables. It also utilizes a deep neural network that identifies the nonlinear relationship between extracted features and luminance degradation. Thereafter, luminance degradation is estimated from burn-in-related variables, and the burn-in phenomenon can be addressed by compensating for luminance degradation. Experiment results revealed that compensation was successfully achieved within an error range of 4.56%, and demonstrated the potential of a new approach that could mitigate the burn-in phenomenon by directly compensating for pixel-level luminance deviation.

Subacute Oral Toxicity Evaluation of Freeze-Dried Powder of Locusta migratoria.

Novel food sources have enormous potential as nutritional supplements. For instance, edible insects are considered as an alternative food source due to their higher protein content; moreover, they are economically efficient reproducers and have high in nutritional value. In this study, we investigated the toxicity of the freeze-dried powder of Locusta migratoria (fdLM), known to contain rich proteins as well as fatty acids. The objective of the present study was to evaluate the subacute toxicity of fdLM in male and female Sprague-Dawley (SD) rats. The SD rats were divided into four groups based on the dosage of fdLM administered: dosage of 0 (vehicle control), 750, 1,500, and 3,000 mg/kg/day were administered for 28 days. Toxicological assessments including observations on food consumption, body and organ weights, clinical signs, mortality, ophthalmologic tests, urinalyses, hematologic tests, clinical chemistry tests, gross findings, and histopathology tests were performed. Clinical signs, urinalyses, hematology, serum biochemistry tests, and organ weight examinations revealed no fdLM-related toxicity. The no-observed-adverse-effect level for fdLM was higher than 3,000 mg/kg/day in rats of both sexes; therefore, fdLM, in conclusion, can be considered safe as an edible alternative human and animal food source material.

Evaluation of Subchronic Oral Dose Toxicity of Freeze-Dried Skimmed Powder of Zophobas atratus Larvae (frpfdZAL) in Rats.

Zophobas atratus (Coleoptera: Tenebrionidae), the giant mealworm beetle, is known as an edible insect containing a high protein content which may serve as new sources of human food and animal feed. However, potential toxicity and food safety analyses of Z. atratus have not been previously investigated. Therefore, in this study, we aimed to evaluate toxicity of freeze-dried skimmed powder of Z. atratus larvae (frpfdZAL), known as the super mealworm. Toxicological assessments were performed at the doses of 1250, 2500, and 5000 mg/kg/day in a 2- and a 13-week oral repeated-dose toxicity study of frpfdZAL in male and female Sprague-Dawley (SD) rats in accordance with the Organisation for Economic Co-operation and Development (OECD) guidelines and the principles of Good Laboratory Practice (GLP). No toxicological changes in clinical signs, body weights, water and food consumption, urinalysis, hematology, clinical biochemistry, gross findings, and histopathological examinations were observed. In conclusion, the no-observed-adverse-effect level (NOAEL) of frpfdZAL was 5000 mg/kg/day and target organ was not identified in both sexes of rats. In addition, frpfdZAL did not induce increases of serum ImmunoglobulinE (IgE), an identifier of allergic reactions in rats. Collectively, these results suggest that frpfdZAL is safe with no adverse effects, and able to be applied as an edible ingredient or other biological uses.

Lactococcus allomyrinae sp. nov., isolated from gut of larvae of Allomyrina dichotoma.

Strain 1JSPR-7T, a facultatively anaerobic bacterium isolated from the gut of larvae of Allomyrina dichotoma raised in Wanju-gun, Republic of Korea, was characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene and rpoB gene sequences showed that strain 1JSPR-7T fell within the genus Lactococcus, forming a compact cluster with the type strain of four subspecies of Lactococcus lactis and Lactococcus taiwanensis. The 16S rRNA gene sequence of strain 1JSPR-7T revealed the highest homology with L. lactissubsp. lactis JCM 5805T (97.3 %) and L. lactissubsp. hordniae NBRC 100931T (97.1 %), and the rpoB gene sequence showed the highest similarity to L. lactissubsp. cremoris DSM 20069T (91.4 %) and L. lactissubsp. tructae L105T (91.4 %). The average nucleotide identity and digital DNA-DNA hybridization values indicated that strain 1JSPR-7T was a novel species of the genus Lacococcus. The major fatty acids (>10 % of the total fatty acids) were summed feature 7 (unknown 18.846, C19 : 1ω6c and/or C19 : 0cyclo ω10c), C16 : 0 and C14 : 0, and the predominant menaquinone was MK-8 with MK-7 as a minor one. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and three unidentified glycolipids with diphosphatidylglycerol as the major one. The cell-wall peptidoglycan was of the A4α type with an interpeptide bridge comprising l-Lys-d-Asp. The DNA G+C content based on the whole genome sequences was 37.4 mol%. Based on the data obtained, strain 1JSPR-7T represents a novel species of the genus Lactococcus, for which the name Lactococcusallomyrinae sp. nov. is proposed. The type strain is 1JSPR-7T (=KACC 19319T=NBRC 113068T).

Fabrication of a Bi2Te3-Based Thermoelectric Module Using Tin Electroplating and Thermocompression Bonding.

A method for directly bonding thermoelectric elements onto copper electrodes without applying a solder paste was developed in this study. A tin coating of thickness approximately 50 µm was deposited via electroplating onto the surface of a Bi2Te3-based thermoelectric element, which had a nickel diffusion barrier layer. The resulting structure was subsequently subjected to direct thermocompression bonding at 250 °C on a hotplate for 3 min at a pressure of 1.1 kPa. Scanning electron microscopy imaging confirmed that a strong and uniform bond was formed at the copper electrode-thermoelectric element interface, and the melted or solidified tin layer remained defect-free. The thermoelectric module fabricated using tin plating had an average bonding strength similar to that fabricated using soldering.

First report of Oryctes rhinoceros nudivirus (Coleoptera: Scarabaeidae) causing severe disease in Allomyrina dichotoma in Korea.

Oryctes rhinoceros nudivirus (OrNV) has been known to cause severe disease in coconut palm rhinoceros beetle, Oryctes rhinoceros, in Southeastern Asia and is used as a biological control to reduce the pest population. Here, we report for the first time that the OrNV may have landed on Korea and may be the major pathogen for diseased larvae of Korean horn beetle, Allomyrina dichotoma. After peroral inoculation, over 60% of infected larvae perished in 6 wk. This viral disease spreads very fast in several locations throughout Korea. This threat not only makes economic loss of local farms rearing A. dichotoma larvae but also may disturb the ecosystem by transmitting to wild A. dichotoma.

Characterization of the molecular features and expression patterns of two serine proteases in Hermetia illucens (Diptera: Stratiomyidae) larvae.

To investigate the molecular scavenging capabilities of the larvae of Hermetia illucens, two serine proteases (SPs) were cloned and characterized. Multiple sequence alignments and phylogenetic tree analysis of the deduced amino acid sequences of Hi-SP1 and Hi-SP2 were suggested that Hi-SP1 may be a chymotrypsin- and Hi-SP2 may be a trypsin-like protease. Hi-SP1 and Hi-SP2 3-D homology models revealed that a catalytic triad, three disulfide bonds, and a substrate-binding pocket were highly conserved, as would be expected of a SP. E. coli expressed Hi-SP1 and Hi-SP2 showed chymotrypsin or trypsin activities, respectively. Hi-SP2 mRNAs were consistently expressed during larval development. In contrast, the expression of Hi-SP1 mRNA fluctuated between feeding and molting stages and disappeared at the pupal stages. These expression pattern differences suggest that Hi-SP1 may be a larval specific chymotrypsin-like protease involved with food digestion, while Hi-SP2 may be a trypsin-like protease with diverse functions at different stages.

Pharmacogenetic regulation of acetylcholinesterase activity in Drosophila reveals the regulatory mechanisms of AChE inhibitors in synaptic plasticity.

We conducted experiments in Drosophila to investigate the consequences of altered acetylcholinesterase (AChE) activity in the nervous system. In ace hypomorphic mutant larvae, the amount of ace mRNA and the activity of AChE both in vivo and in vitro were significantly reduced compared with those of controls. Reduced Ace in Drosophila larvae resulted in significant down-regulation of branch length and the number of boutons in Type 1 glutamatergic neuromuscular junctions (NMJs). These defects in ace hypomorphic mutant larvae were suppressed when Musca domestica AChE was transgenically expressed. Because AChE inhibitors are utilized for medications for Alzheimer's disease, we investigated whether pharmacological inhibition of AChE activity induced any synaptic defects. We found that controls exposed to a sublethal dose of DDVP phenocopied the synaptic structural defects of the ace hypomorphic mutant. These results suggest that down-regulation of AChE activity, regardless of whether it is due to genetic or pharmacological manipulations, results in altered synaptic architecture. Our study suggests that exposure to AChE inhibitors for 6-12 months may induce altered synaptic architectures in human brains with Alzheimer's diseases, similar to those reported here. These changes may underlie or contribute to the loss of efficacy of AChE inhibitors after prolonged treatment.