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Simple Summary: Fish meal is commonly used as the main protein source in aquafeeds. However, the increasing global demand and the overfishing of wild fish stocks commonly used as fish meal sources have restricted supply and increased the price of fish meal in recent decades. To achieve the goal of sustainable fish culture, fish meal replacement with an alternative source that is inexpensive and year-round available in aquafeeds is highly needed. Meanwhile, more than half of the total tuna is trashed as waste in tuna-canning processing plants. In the current study, we investigated the dietary substitution effect of fish meal with tuna by-product meal on growth, feed availability, and biochemical composition of the early stage of juvenile rockfish, one of the most widely farmed marine fish species in Eastern Asia. The results indicated that up to 40% of fish meal could be substituted with tuna by-product meal in the diets of rockfish without negatively influencing the growth, feed availability, and hematological parameters of rockfish. With the dietary replacement of 40% fish meal with tuna by-product meal in practical feeding, rockfish farmers are able to produce the highest economic return. This experiment was performed to assess the substitution impact of fish meal (FM) with tuna by-product meal (TBM) in feeds on growth and feed availability of the early stage of juvenile rockfish (S. schlegeli). Six experimental feeds were prepared to be isonitrogenous and isolipidic. Fifty-five percent of FM was contained in the control (Con) diet. In the Con diet, 20, 40, 60, 80, and 100% FM were replaced by TBM, named the TBM20, TBM40, TBM60, TBM80, and TBM100 diets, respectively. A total of 540 early-stage juvenile rockfish averaging 2.4 g was divided into 18 tanks and hand-fed to satiation for 56 days. Weight gain and feed consumption of rockfish fed the TBM20 and TBM40 diets were comparable to rockfish fed the Con diet. The specific growth rate (SGR) of rockfish fed the Con diet was comparable to rockfish fed the TBM20, TBM40, and TBM60 diets. Feed efficiency, biometric indices, hematological parameters, proximate composition, and amino acid profiles of rockfish were not impacted by dietary treatments. The economic profit index (EPI) of the Con, TBM20, and TBM40 diets were higher than that of all other diets. FM up to 40% could be substitutable with TBM in the diets of rockfish without deteriorating weight gain and feed consumption, but producing the highest EPI. [ABSTRACT FROM AUTHOR]

Anaerobic ciliates are key organisms for studying adaptations to an anaerobic lifestyle, the evolution of eukaryotic cell organelles, mechanisms of energy metabolism, and symbiosis with prokaryotes; however, the biodiversity of their marine representatives remains poorly known. In this study, three species of ciliates belonging to the class Plagiopylea, i.e. Trimyema foissneri sp. nov. Plagiopyla rariseta sp. nov. and Plagiopyla frontata , collected from various marine anoxic habitats from two geographically distant continents, Asia and North America, were investigated using morphological and molecular methods. Trimyema foissneri can be recognized by three complete somatic ciliary girdles, special arrangement of kinetosomes near the anterior end of the oral kineties, and the presence of a ventrolateral fragment. Plagiopyla rariseta is distinguished by sparse cilia on the frontal region and particular orientation of the buccal cavity. Plagiopyla frontata is newly recorded and is redescribed in detail and redefined based on new populations. Phylogenetic analyses based on the small subunit ribosomal ribonucleic acid (SSU rRNA) gene supported the generic assignment of the three species and corroborated the monophyly of the families Trimyemidae and Plagiopylidae. An improved key to the identification of the valid species of genus Trimyema is also supplied. [ABSTRACT FROM AUTHOR]

While much research has been undertaken on firms' internationalisation, much less has been written on internationalisation's other side, localisation. Yet with the rise of emerging economies, especially Chinese transnational corporations, localisation has become an increasingly significant. This article examines the localisation experience of two Chinese telecommunications enterprises - Huawei and ZTE - in Malaysia. By holding these factors constant (the ceteris paribus assumption), several dimensions of localisation are revealed. They are product, workforce, technology, organisation and management. Firm-specific factors matter both in accounting for inter-firm similarities and differences in the manner they localised. Enterprise ownership is also important in explaining firm performance and host countries' perception of these firms. Leadership styles of these enterprises' founders also matter. Together, these factors affect the differential pace of firms' internationalisation and localisation. [ABSTRACT FROM AUTHOR]

• Assess the performances of GNSS positioning and integer ambiguity resolution based on the satellite-related corrections from different regional networks. • Prove the feasibility of the interchangeable network corrections in high precision positioning and successful fixing ambiguity. • Provide a strategy that could improve the robustness and integrity of the commercial positioning services for small- or medium-sized enterprises. • Discuss the potential factors that influence the ambiguity fixed positioning solutions by using different network corrections. BeiDou Navigation Satellite System (BDS) has contributed to, extended, and densified the concept of satellite navigation since its first generation. Although the traditional precise point positioning (PPP) technique has been gradually replaced by its successor, that is, PPP-IAR by means of integer ambiguity resolution, most of the current studies regarding BDS-only positioning are only in the scientific sense and thus lack the feasibility of implementing PPP-IAR in societal applications. This is because building up a global or a large regional network with hundreds of reference stations is less realistic for small- and medium-sized enterprises. This manuscript aims to bridge the gap between scientific research and societal applications and thereby expand the BDS commercial services to various fields of navigation, positioning and timing. Three regional networks with the approximate distances of 470 k m , 1100 k m , and 1700 k m in Eastern Asia are selected, and each network contains no more than 15 reference stations and 5 user stations. First, the satellite-related corrections generated from individual networks are compared to each other, and the results show that the differences of satellite clock corrections vary from 0.1 to 0.15 m , whereas those of satellite phase delay corrections vary from 0.39 to 0.53 m. Then, users apply the satellite corrections not only from their own network but from the other two networks to verify if these corrections are interchangeable between different networks because it would be meaningful for improving the robustness and integrity of the positioning services once these corrections can be backups for each other. The results show that the ambiguity fixed kinematic positioning can always achieve centimeter accuracy level; however, ambiguity wrong fixing problems may appear when a user applies another network's corrections. Besides, users may expect an 8.5 m i n time span to achieve a centimeter-accuracy level if they apply the satellite corrections from their own network. Though it is well known that not so much the number of epochs but the change of geometry that contributes to the determination of the positions, a high sampling rate does speed up ambiguity fixing by means of a large number of observations within a short period. The experiments of 1 s interval indicate that the convergence time of centimeter level positioning accuracy can be reduced to 2 m i n under some conditions. [ABSTRACT FROM AUTHOR]

As one of the most obvious phenotypic traits, the coat color of sheep is an ideal model to study the genetic mechanisms underlying coat color varieties of mammals. One distinguishable coat color is the black-headed type, such as the famous black-headed Dorper sheep from Africa and Bayinbuluke sheep from Asia. In this study, we compared the genome sequences of black-headed and all-white sheep to identify causative genes for the black-headed sheep, including black-headed Dorper vs. white-headed Dorper, as well as Bayinbuluke (black-headed) vs. Small-tailed Han (all-white). The most differentiating region between black-headed sheep and all-white sheep was found to harbor a haplotype covering melanocortin receptor 1 (MC1R) gene. The share of this haplotype by the black-headed sheep from Africa and Asia suggested that the convergent change in the MC1R region is likely to determine this unique coat color. Two missense mutations (g. 14251947T > A and g. 14252090G > A) within this haplotype of MC1R gene were found. We further analyzed whole genome sequence data of 460 worldwide sheep with diverse coat colors and confirmed the association between the MC1R haplotype with pigmentation variations. Our study provides novel insights into coat color genetics in sheep and expands our knowledge of the link between MC1R gene and varying pigmentation patterns in sheep., (© The Author(s) 2023. Published by Oxford University Press on behalf of the American Society of Animal Science.)