Complete genome sequence of a Megalocytivirus (family Iridoviridae) associated with turbot mortality in China

<p>Abstract</p> <p>Background</p> <p>Turbot reddish body iridovirus (TRBIV) causes serious systemic diseases with high mortality in the cultured turbot, <it>Scophthalmus maximus</it>. We here sequenced and analyzed the complete genome of TRBIV, which was identified in Shandong province, China.</p> <p>Results</p> <p>The genome of TRBIV is a linear double-stranded DNA of 110,104 base pairs, comprising 55% G + C. Total 115 open reading frames were identified, encoding polypeptides ranging from 40 to 1168 amino acids. Amino acid sequences analysis revealed that 39 of the 115 potential gene products of TRBIV show significant homology to other iridovirus proteins. Phylogenetic analysis of conserved genes indicated that TRBIV is closely related to infectious spleen and kidney necrosis virus (ISKNV), rock bream iridovirus (RBIV), orange-spotted grouper iridovirus (OSGIV), and large yellow croaker iridovirus (LYCIV). The results indicated that TRBIV belongs to the genus <it>Megalocytivirus </it>(family Iridoviridae).</p> <p>Conclusions</p> <p>The determination of the genome of TRBIV will provide useful information for comparative study of Megalocytivirus and developing strategies to control outbreaks of TRBIV-induced disease.</p

1DFormer: a Transformer Architecture Learning 1D Landmark Representations for Facial Landmark Tracking

Recently, heatmap regression methods based on 1D landmark representations have shown prominent performance on locating facial landmarks. However, previous methods ignored to make deep explorations on the good potentials of 1D landmark representations for sequential and structural modeling of multiple landmarks to track facial landmarks. To address this limitation, we propose a Transformer architecture, namely 1DFormer, which learns informative 1D landmark representations by capturing the dynamic and the geometric patterns of landmarks via token communications in both temporal and spatial dimensions for facial landmark tracking. For temporal modeling, we propose a recurrent token mixing mechanism, an axis-landmark-positional embedding mechanism, as well as a confidence-enhanced multi-head attention mechanism to adaptively and robustly embed long-term landmark dynamics into their 1D representations; for structure modeling, we design intra-group and inter-group structure modeling mechanisms to encode the component-level as well as global-level facial structure patterns as a refinement for the 1D representations of landmarks through token communications in the spatial dimension via 1D convolutional layers. Experimental results on the 300VW and the TF databases show that 1DFormer successfully models the long-range sequential patterns as well as the inherent facial structures to learn informative 1D representations of landmark sequences, and achieves state-of-the-art performance on facial landmark tracking

Modeling And Experimental Study On A Direct Expansion Based Enhanced Dehumidification Air Conditioning System

Direct expansion (DX) air conditioning (A/C) systems are widely used for controlling indoor air temperature and humidity in various buildings in hot and humid climates since they are simpler and more energy efficient, and generally cost less to own and maintain. However, it is often problematic for a DX A/C system to provide desired humidity control due to the current system design trends, variable weather conditions and the commonly used control strategies for DX A/C systems. Therefore, a standalone DX based enhanced dehumidification air conditioning (EDAC) system is proposed to provide suitable indoor humidity control at different seasons. There are two evaporators in the EDAC system, thus it could act as a dehumidifier (ADO mode) on the days when less or no additional cooling is required by employing one evaporator as a reheating coil, or act as an enhanced dehumidification A/C system (EDAC mode) by functioning two evaporators to separately deal with sensible and latent cooling. A prototype experimental EDAC system was established in a laboratory. The operational characteristics of the EDAC system at ADO mode in terms of the moisture removal capacity (MRC), the specific moisture extraction rate (SMER) and the resulted supply air temperature were investigated and reported in this paper. Firstly, the experimental results on operational characteristics are reported. Secondly, the development of a steady-state mathematical model for the ADO mode of the EDAC system is presented. The developed model was thereafter used to study the influence of different sizes of the evaporator and the reheating coil on the operational characteristic of the EDAC system at ADO mode. The study results could lead to a better understanding of the operational characteristics of the EDAC system, facilitating its design, operation and control

Real-time study of rapid spread of antibiotic resistance plasmid in biofilm using microfluidics

Gene transfer in biofilms is known to play an important role in antibiotic resistance dissemination. However, the process remains poorly understood. In this study, microfluidics with time-lapse imaging was used for real-time monitoring of plasmid-mediated horizontal gene transfer (HGT) in biofilms. Pseudomonas putida KT2440 harboring an antibiotic resistance plasmid RP4 was chosen as the donor while Escherichia coli and activated sludge bacteria were used as the recipient cells. Dynamic features of the transfer process, including the transfer rate, cell growth rate and kinetic changes of the transfer frequency, were determined. It was found that the routes for gene transfer strongly depend on the structure and composition of a biofilm. While intraspecies HGT is essential to initiate a transfer event, the secondary retransfer from transconjugants to the same species is more efficient and can cause cascading gene spread in single-strain biofilms. For the activated sludge biofilm, only small and scattered colonies formed and vertical gene transfer appears to be the dominant route after initial intraspecies transfer. Furthermore, more than 46% of genera in the activated sludge were permissive to plasmid RP4, many of which are associated with human pathogens. These phenomena imply early prevention and interruptions to biofilm structure could provide an effect way to inhibit rapid antibiotic resistance gene spread and reduce the likelihood of catastrophic events associated with antibiotic resistance

Stereoselective alkoxycarbonylation of unactivated C(sp^3)–H bonds with alkyl chloroformates via Pd(II)/Pd(IV) catalysis

Several examples on Pd-catalysed carbonylation of methyl C(sp^3)–H bonds with gaseous CO via Pd(II)/Pd(0) catalysis have been reported. However, methylene C(sp^3)–H carbonylation remains a great challenge, largely due to the lack of reactivity of C–H bonds and the difficulty in CO migratory insertion. Herein, we report the stereoselective alkoxycarbonylation of both methyl and methylene C(sp^3)–H bonds with alkyl chloroformates through a Pd(II)/Pd(IV) catalytic cycle. A broad range of aliphatic carboxamides and alkyl chloroformates are compatible with this protocol. In addition, this process is scalable and the directing group could be easily removed under mild conditions with complete retention of configuration

Biochemical mechanism of phosphorus limitation impairing nitrogen fixation in diazotrophic bacterium <i>Klebsiella variicola</i> W12

Introduction: Biological nitrogen (N) fixation (BNF) plays a key role in nitrogen supply in agricultural and natural ecosystems. Harnessing BNF can substantially reduce dependence on chemical fertilizer in agroecosystems and hence can contribute to sustainable agriculture. However, a number of field studies have demonstrated that BNF can be largely suppressed in phosphorus (P)-deficient environments, while the underlying mechanism is not well understood.Materials &amp; Methods: In this study, comparative proteomics and lipidomics analyses were conducted on a diazotrophic bacterium Klebsiella variicola W12 under P-deficient and P-replete conditions to gain insight into how P availability affects N fixation.Results: Under P deficiency, N fixation activity of K. variicola W12 was severely repressed. In response to P limitation, the bacterium synthesized P-free ornithine lipids to replace glycerophospholipids in its membrane to reduce cellular demand for P. Comparative proteomics showed that P limitation resulted in upregulation of the PhoBR two-component system, a range of organic and inorganic P uptake and transport systems, while nitrogenase and N-fixation-related transcriptional regulators NifL and NifA were downregulated.Conclusion: These results revealed lipid renovation as an adaptation strategy for N2-fixing microbes to survive under P stress and provided biochemical evidence on how P availability regulates BNF. A conceptual model of N–P coupling at the microbial metabolism level is therefore proposed. Our study provides a simple yet plausible explanation of how P deficiency suppresses BNF observed in the field and highlights the importance of regulating P availability to maximize the potential of BNF in agroecosystems for agriculture sustainable production

Biochemical mechanism of phosphorus limitation impairing nitrogen fixation in diazotrophic bacterium <i>Klebsiella variicola</i> W12

Introduction: Biological nitrogen (N) fixation (BNF) plays a key role in nitrogen supply in agricultural and natural ecosystems. Harnessing BNF can substantially reduce dependence on chemical fertilizer in agroecosystems and hence can contribute to sustainable agriculture. However, a number of field studies have demonstrated that BNF can be largely suppressed in phosphorus (P)-deficient environments, while the underlying mechanism is not well understood.Materials &amp; Methods: In this study, comparative proteomics and lipidomics analyses were conducted on a diazotrophic bacterium Klebsiella variicola W12 under P-deficient and P-replete conditions to gain insight into how P availability affects N fixation.Results: Under P deficiency, N fixation activity of K. variicola W12 was severely repressed. In response to P limitation, the bacterium synthesized P-free ornithine lipids to replace glycerophospholipids in its membrane to reduce cellular demand for P. Comparative proteomics showed that P limitation resulted in upregulation of the PhoBR two-component system, a range of organic and inorganic P uptake and transport systems, while nitrogenase and N-fixation-related transcriptional regulators NifL and NifA were downregulated.Conclusion: These results revealed lipid renovation as an adaptation strategy for N2-fixing microbes to survive under P stress and provided biochemical evidence on how P availability regulates BNF. A conceptual model of N–P coupling at the microbial metabolism level is therefore proposed. Our study provides a simple yet plausible explanation of how P deficiency suppresses BNF observed in the field and highlights the importance of regulating P availability to maximize the potential of BNF in agroecosystems for agriculture sustainable production

ChatGPT for Shaping the Future of Dentistry: The Potential of Multi-Modal Large Language Model

The ChatGPT, a lite and conversational variant of Generative Pretrained Transformer 4 (GPT-4) developed by OpenAI, is one of the milestone Large Language Models (LLMs) with billions of parameters. LLMs have stirred up much interest among researchers and practitioners in their impressive skills in natural language processing tasks, which profoundly impact various fields. This paper mainly discusses the future applications of LLMs in dentistry. We introduce two primary LLM deployment methods in dentistry, including automated dental diagnosis and cross-modal dental diagnosis, and examine their potential applications. Especially, equipped with a cross-modal encoder, a single LLM can manage multi-source data and conduct advanced natural language reasoning to perform complex clinical operations. We also present cases to demonstrate the potential of a fully automatic Multi-Modal LLM AI system for dentistry clinical application. While LLMs offer significant potential benefits, the challenges, such as data privacy, data quality, and model bias, need further study. Overall, LLMs have the potential to revolutionize dental diagnosis and treatment, which indicates a promising avenue for clinical application and research in dentistry

Current insights in the preclinical study of palatal wound healing and oronasal fistula after cleft palate repair

Poor palatal wound healing after cleft palate repair could lead to unfavorable prognosis such as oronasal fistula (ONF), which might affect the patient’s velopharyngeal function as well as their quality of life. Thus, restoring poor palatal wound healing for avoiding the occurrence of ONF should be considered the key to postoperative care after cleft palate repair. This review provided current insights in the preclinical study of poor palatal wound healing after cleft palate repair. This review comprehensively introduced the animal model establishment for palatal wound healing and related ONF, including the models by mice, rats, piglets, and dogs, and then demonstrated the aspects for investigating poor palatal wound healing and related treatments, including possible signaling pathways that could be involved in the formation of poor palatal wound healing, the related microbiota changes because of the deformity of palatal structure, and the studies for potential therapeutic strategies for palatal wound healing and ONF. The purpose of this review was to show the state of the art in preclinical studies about palatal wound healing after cleft palate repair and to show the promising aspects for better management of palatal wound healing