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Abstract Background De-novo-designed synthetic transcriptional regulators have great potential as the genetic parts for constructing complex multilayered gene circuits. The design flexibility afforded by advanced nucleic acid sequence design tools vastly expands the repertoire of regulatory elements for circuit design. In principle, the design space of synthetic regulators should allow for the construction of regulatory circuits of arbitrary complexity; still, the orthogonality and robustness of such components have not been fully elucidated, thereby limiting the depth and width of synthetic circuits. Results In this work, we systematically explored the design strategy of synthetic transcriptional regulators, termed switchable transcription terminators. Specifically, by redesigning key sequence domains, we created a high-performance switchable transcription terminator with a maximum fold change of 283.11 upon activation by its cognate input RNA. Further, an automated design algorithm was developed for these elements to improve orthogonality for a complex multi-layered circuit construction. The resulting orthogonal switchable transcription terminators could be used to construct a three-layer cascade circuit and a two-input three-layer OR gate. Conclusions We demonstrated a practical strategy for designing standardized regulatory elements and assembling modular gene circuits, ultimately laying the foundation for the streamlined construction of complex synthetic gene circuits.

Abstract Recognition of signaling molecules for coordinated regulation of target genes is a fundamental process for biological systems. Cells often rely on transcription factors to accomplish these intricate tasks, yet the subtle conformational changes of protein structures, coupled with the complexity of intertwined protein interaction networks, pose challenges for repurposing these for bioengineering applications. This study introduces a novel platform for ligand‐responsive gene regulation, termed START (Synthetic Trans‐Acting Riboswitch with Triggering RNA). Inspired by the bacterial ligand sensing system, riboswitch, and the synthetic gene regulator, toehold switch, the START platform enables the implementation of synthetic biosensors for various ligands. Rational sequence design with targeted domain optimization yields high‐performance STARTs with a dynamic range up to 67.29‐fold and a tunable ligand sensitivity, providing a simple and intuitive strategy for sensor engineering. The START platform also exhibits modularity and composability to allow flexible genetic circuit construction, enabling seamless implementation of OR, AND, and NOT Boolean logic gates for multiple ligand inputs. The START design principle is capable of broadening the suite of synthetic biosensors for diverse chemical and protein ligands, providing a novel riboregulator chassis for synthetic biology and bioengineering applications.

Organic light-emitting diodes (OLEDs) have demonstrated remarkable advancements in both device lifetime and luminous efficiency. However, insufficient operation lifetime due to device degradation remains a major hurdle, especially for brighter devices. Understanding the degradation mechanisms of OLEDs due to the degradation of functional materials and the formation of defects in device architectures continues to be a significant challenge. Herein, we evaluate the degradation characteristics by scrutinizing the electrical and optical properties, as well as analyzing the charge carrier dynamics in pristine and aged states of phosphorescent OLEDs (PhOLEDs). We show that degradation mechanisms in PhOLEDs can be elucidated in terms of the ideality factors of current and luminance in pristine and aged device states. The consistent shifts in distinct ideality factors across various states points out that the device degradation is attributed to the deterioration of the guest material, i.e. green-light-emitting phosphorescent material. Conversely, the incongruity in ideality factor changes between the two states indicates that the degradation results from the deterioration of non-light-emitting material. Subsequent characterization experiments provide further evidence that this degradation is primarily attributed to the deterioration of CBP-host material. The thorough understanding of degradation mechanisms established in this study can contribute to realizing the highly reliable PhOLEDs with a long lifetime.

Abstract Background Surgical resection remains the mainstay of treatment for cardiac sarcoma, a rare but lethal disease. Achieving complete removal of a large-sized left ventricular sarcoma remains a challenge even with various surgical approaches that have been employed. Case presentation We present a case of a 74-year-old woman with shortness of breath who underwent surgical removal of a primary cardiac sarcoma, measuring 6 × 3.5 × 3 cm, attached to the septum of the left ventricle and caused sub-aortic valve obstruction. Transaortic approach was chosen and the access to this entire huge mass was enabled by using interim partial resection which created a space for further dissection and subsequent deeper endoscopic views. The further dissection was finally able to be advanced on the apex, and the residual mass was completely resected with gross tumor-free margins. Conclusion Interim partial resection and endoscopic guidance can highly facilitate the transaortic removal of even large left ventricular sarcomas.

Background: This study evaluated the early, 1-year, and 3-year graft patency rates and mid-term clinical outcomes after no-touch saphenous veins (NT-SVs) were used as aortocoronary grafts in coronary artery bypass grafting (CABG). Methods: In total, 101 patients who underwent CABG using NT-SVs as aortocoronary grafts were included. The 2 most common indications for performing aortocoronary grafting with NT-SVs were unavailability of the left internal thoracic artery (n=36) and moderate lesions where flow competition was expected (n=27). Early (median, 1 day; interquartile range [IQR], 1–2 days), 1-year (median, 13 months; IQR, 11–16 months), and 3-year (median, 34 months; IQR, 27–41 months) graft angiography was performed in 98 (97.0%), 84 (83.2%), and 40 patients (39.6%), respectively. The median follow-up duration was 43 months (IQR, 13–76 months). Overall survival rates and the cumulative incidence of major adverse cardiac events were evaluated. Results: The operative mortality rate was 2% (2 of 101 patients). Early postoperative patency rates for overall and aortocoronary NT-SV grafts were 98.2% (223 of 227 distal anastomoses) and 98.2% (164 of 167), respectively. The 1- and 3-year patency rates for aortocoronary SV grafts were 94.9% (131 of 138) and 90.6% (58 of 64), respectively. The overall survival rates at 5 and 10 years were 81.7% and 59%, respectively. The cumulative incidence of major adverse cardiac events at 5 and 10 postoperative years was 20.7% and 39%, respectively. Conclusion: The feasibility of using NT-SVs as aortocoronary grafts in CABG was shown in this study, based on the graft patency rates up to 3 years and the mid-term clinical outcomes.

This paper is a comparative study of pole–slot combinations with fractional slot concentrated windings in an outer rotor permanent magnet synchronous generator (ORPMSG) for a hybrid drone system. Fractional slot machines have been studied for automotive applications because of their high performance and simple winding manufacturing, compared with those of integer slot machines. In this study, four pole–slot combinations of ORPMSG with fractional slot concentrated windings were selected for comparison with the performance of the hybrid drone system. Based on the results of a finite element analysis (FEA), the machines were analyzed for cogging torque, back electromagnetic force (BEMF), torque, and electromagnetic loss under the same conditions as the machine specifications. Among the four pole–slot combinations of the ORPMSM, a one pole–slot model of the ORPMSG was selected, considering the performances of the machines. The selected pole–slot model of the ORPMSG was manufactured, and experiments were conducted on the manufactured model to verify the FEA results. Finally, the effectiveness of the comparative study of pole–slot combination with fractional slot concentrated winding in ORPMSM was verified by comparing the FEA and experimental results.

Abstract Background Toll-like receptor 7 (TLR7) is an endosomal TLR activated by single-stranded RNA, including endogenous microRNAs. Although TLR7 is known to promote inflammatory responses in pathophysiological conditions, its role in renal fibrosis has not been investigated. Here, we aim to investigate the inflammatory roles of TLR7 in kidney inflammation and fibrosis. Methods TLR7 knockout mice (Tlr7 −/−) subjected to AD-induced kidney injury were utilized to examine the role of TLR7 in kidney fibrosis. To elucidate the role of TLR7 in renal epithelial cells, NRK52E rat renal tubule epithelial cells were employed. Results Under fibrotic conditions induced by an adenine diet (AD), TLR7 was significantly increased in damaged tubule epithelial cells, where macrophages were highly infiltrated. TLR7 deficiency protected against AD-induced tubular damage, inflammation, and renal fibrosis. Under in vitro conditions, TLR7 activation increased NF-κB activity and induced chemokine expression, whereas TLR7 inhibition effectively blocked NF-κB activation. Furthermore, among the known TLR7 endogenous ligands, miR-21 was significantly upregulated in the tubular epithelial regions. In NRK52E cells, miR-21 treatment induced pro-inflammatory responses, which could be blocked by a TLR7 inhibitor. When the TLR7 inhibitor, M5049, was administered to the AD-induced renal fibrosis model, TLR7 inhibition significantly attenuated AD-induced renal inflammation and fibrosis. Conclusions Overall, activation of TLR7 by endogenous miR-21 in renal epithelial cells contributes to inflammatory responses in a renal fibrosis model, suggesting a possible therapeutic target for the treatment of renal fibrosis. Video Abstract

Most SERS-active nanostructures suffer from low robustness against misalignment to field polarization. Here, the authors demonstrate three-dimensional nanoframes of octahedral geometry, with two rims engraved on each facet, as polarization-independent SERS nanoprobes.

Chronic kidney disease (CKD) is a kidney structure and function abnormality. CKD development and progression are strongly influenced by oxidative stress and inflammatory responses, which can lead to tubulointerstitial fibrosis. Unfortunately, there are no effective or specific treatments for CKD. We investigated the potential of the thiobarbiturate-derived compound MHY1025 to alleviate CKD by reducing oxidative stress and inflammatory responses. In vitro experiments using NRK52E renal tubular epithelial cells revealed that MHY1025 significantly reduced LPS-induced oxidative stress and inhibited the activation of the NF-κB pathway, which is involved in inflammatory responses. Furthermore, treatment with MHY1025 significantly suppressed the expression of fibrosis-related genes and proteins induced by TGFβ in NRK49F fibroblasts. Furthermore, we analyzed the MHY1025 effects in vivo. To induce kidney fibrosis, mice were administered 250 mg/kg folic acid (FA) and orally treated with MHY1025 (0.5 mg/kg/day) for one week. MHY1025 effectively decreased the FA-induced inflammatory response in the kidneys. The group treated with MHY1025 exhibited a significant reduction in cytokine and chemokine expression and decreased immune cell marker expression. Decreased inflammatory response was associated with decreased tubulointerstitial fibrosis. Overall, MHY1025 alleviated renal fibrosis by directly modulating renal epithelial inflammation and fibroblast activation, suggesting that MHY1025 has the potential to be a therapeutic agent for CKD.

After COVID-19, face-to-face learning was changed to online learning. However, very few effective online learning methods were available regarding physical education. Therefore, this study aimed to examine the modeling effects on learning ballet movement in the online system. We aimed to find effective modeling presentations based on objective information, expert assessments, and a kinematic approach. The study included 36 individuals who were divided into an expert modeling group, a self-modeling group, and controls. Participants performed 60 trials of Pas de basque in the acquisition phase and 10 trials without a demonstration video after 24 h. 10 min later, the reversed Pas de basque was conducted for the retention test. All groups showed improved performance after the acquisition phase, which indicated that the modeling presentation was effective despite adopting an online learning system. However, higher expert scores and more accurate joint movements were shown in the expert modeling group compared to the other groups. Therefore, expert modeling seems to be the most effective method for learning high-difficulty tasks with jumps and turns.

Gene therapy is an innovative approach in the field of regenerative medicine. This therapy entails the transfer of genetic material into a patient’s cells to treat diseases. In particular, gene therapy for neurological diseases has recently achieved significant progress, with numerous studies investigating the use of adeno-associated viruses for the targeted delivery of therapeutic genetic fragments. This approach has potential applications for treating incurable diseases, including paralysis and motor impairment caused by spinal cord injury and Parkinson’s disease, and it is characterized by dopaminergic neuron degeneration. Recently, several studies have explored the potential of direct lineage reprogramming (DLR) for treating incurable diseases, and highlighted the advantages of DLR over conventional stem cell therapy. However, application of DLR technology in clinical practice is hindered by its low efficiency compared with cell therapy using stem cell differentiation. To overcome this limitation, researchers have explored various strategies such as the efficiency of DLR. In this study, we focused on innovative strategies, including the use of a nanoporous particle-based gene delivery system to improve the reprogramming efficiency of DLR-induced neurons. We believe that discussing these approaches can facilitate the development of more effective gene therapies for neurological disorders.

In this paper, the design of novel slotless permanent magnet synchronous motor (PMSM) for a collaborative robot was studied considering the manufacture process of winding. The winding manufacture process of novel slotless PMSM was proposed in three steps. First, the two types of coil units were manufactured based on the winding jig to assemble the coil units. Second, the coil unit was manufactured using the injection molding based on the plastic material such as polyphenylene sulfide (PPS). Third, the units of the coil were assembled to form a stator winding. Considering this manufacture process of winding, the slotless motor design was studied for the collaborative robot. For the design and analysis of slotless motor, finite element analysis (FEA) was performed through ANSYS Maxwell. The electromagnetic performance was analyzed according to the pole-slot combination. Considering the space of the collaborative robot, the basic model was designed. Based on the basic model, the electromagnetic performance was analyzed according to the design parameters such as the thickness of magnet and yoke and turns per slot. Considering the torque and current density, the final model was designed. To verify the FEA results, the slotless motor was manufactured and the experiment and FEA results were compared.

The peroxisome proliferator-activated receptor (PPAR) nuclear receptor has been an interesting target for the treatment of chronic diseases. Although the efficacy of PPAR pan agonists in several metabolic diseases has been well studied, the effect of PPAR pan agonists on kidney fibrosis development has not been demonstrated. To evaluate the effect of the PPAR pan agonist MHY2013, a folic acid (FA)-induced in vivo kidney fibrosis model was used. MHY2013 treatment significantly controlled decline in kidney function, tubule dilation, and FA-induced kidney damage. The extent of fibrosis determined using biochemical and histological methods showed that MHY2013 effectively blocked the development of fibrosis. Pro-inflammatory responses, including cytokine and chemokine expression, inflammatory cell infiltration, and NF-κB activation, were all reduced with MHY2013 treatment. To demonstrate the anti-fibrotic and anti-inflammatory mechanisms of MHY2013, in vitro studies were conducted using NRK49F kidney fibroblasts and NRK52E kidney epithelial cells. In the NRK49F kidney fibroblasts, MHY2013 treatment significantly reduced TGF-β-induced fibroblast activation. The gene and protein expressions of collagen I and α-smooth muscle actin were significantly reduced with MHY2013 treatment. Using PPAR transfection, we found that PPARγ played a major role in blocking fibroblast activation. In addition, MHY2013 significantly reduced LPS-induced NF-κB activation and chemokine expression mainly through PPARβ activation. Taken together, our results suggest that administration of the PPAR pan agonist effectively prevented renal fibrosis in both in vitro and in vivo models of kidney fibrosis, implicating the therapeutic potential of PPAR agonists against chronic kidney diseases.

Hydrogen production via water splitting has been extensively explored over the past few decades, and considerable effort has been directed toward finding more reactive and cost-effective electrocatalysts by engineering their compositions, shapes, and crystal structures. In this study, we developed hierarchical cobalt phosphide (Co-P) nanosphere assemblies as non-noble metal electrocatalysts via one-step electrodeposition. The morphologies of the Co-P nanostructures and their electrocatalytic activities towards the hydrogen evolution reactions (HER) were controlled by the applied potentials during electrodeposition. The physicochemical properties of the as-prepared Co-P nanostructures in this study were characterized by field-emission scanning electron microscopy, X-ray photoemission spectroscopy and X-ray diffraction. Linear sweep voltammetry revealed that the Co-P grown at −0.9 V showed the best HER performance exhibiting the highest electrochemical active surface area and lowest interfacial charge transfer resistance. The Co-P electrocatalysts showed superior long-term stability to electrodeposited Pt, indicating their potential benefits.

Indoor microbes are a key component of air contamination that causes human health risks. However, compared with the aquatic and soil environment, microbial diversity and taxonomic structure and composition in subway facility are not well characterized. This study tries to explore surface bacterial communities by using swabs collected from four global subway facilities, such as Busan, Boston, Mexico City, and Moscow using 16S rRNA gene amplicon sequencing. The alpha-diversities on bacterial communities were significantly different between Moscow and other samples, despite the different sample characteristics among Busan, Boston, Mexico City samples. For bacterial taxonomic composition, three phyla such as Actinobacteria (41.1%), Proteobacteria (27.7%), and Firmicutes (18.9%), were most dominant among all samples, indicating that there was no significance (p > 0.05). The subway station surface samples were mostly dominated by Gram-positive bacteria, including genera Corynebacterium, Staphylococcus, and Streptococcus. PCoA analysis also revealed that the Moscow bacterial communities were clearly separated from others. In addition, core genera were only shared 75 genera among all samples, but 486 genera were shared with three global stations, such as Busan, Boston and Mexico City. These results suggested that the human activity and geographical environment potentially affect the establishment of the bacterial community. Although this study provided basic information on surface bacterial communities in the subway system, there is a remaining unknown microbiome in the indoor air environment. Therefore, we consistently try to understand the indoor environment’s microbial ecology in the subway system.

The synthesis of anisotropic nanoparticles with structural diversity and complexity in a rational and systematic fashion is rare. Here, the authors demonstrate a rational and stepwise synthetic strategy for nanoplates with a high degree of intricacy, leading to a gallery of shapes such as rings, triangles, hexagons, and tripods, with tailorable single or double frames.

Indoor microbes are readily transmitted among humans in indoor environments. Therefore, this study employed 16S rRNA gene and ITS amplicon profiling to investigate the dust-associated bacterial and fungal communities in six indoor facilities in Busan, South Korea. The collected samples were categorized into two groups: indoor multiple-use facilities (MUFs), including a public bathing facility, business office, and food court; and public transportation facilities (PTFs), including two subway stations and an airport. The bacterial diversity in the MUF samples was significantly higher than the fungal diversity (p < 0.05). However, no significant differences between bacterial and fungal diversity were observed in PTF samples (p > 0.05). Moreover, the abundances of certain microbial taxa varied, suggesting that the microbial community structure was primarily determined by the source environment. Gram-positive bacterial genera, such as Corynebacterium, Kocuria, and Staphylococcus—all of which originated in the natural environment—were relatively predominant in the MUF samples; the Aspergillus, Penicillium, and Malassezia genera, which are human commensal taxa, were relatively more predominant in the PTF samples. These results suggest that different microbial communities can be formed depending on the purpose of the indoor facility type, level of passenger traffic, and surrounding environment. The findings of this study may help researchers understand indoor microbial communities in multi-use and transportation facilities.

Eddy covariance (EC) method has been used to measure CO2 fluxes over various ecosystems. Recently, the EC method has been also deployed in urban areas to measure CO2 fluxes. Urban carbon cycle is complex because of the additional anthropogenic processes unlike natural ecosystems but the EC method only measures the net sum of all CO2 sources and sink. This limitation of the EC method hinders us from the underlying processes of the carbon cycle, and it is necessary to partition the net CO2 fluxes into individual contributions for a better understanding of the urban carbon cycle. Here we propose a statistical method to partition CO2 fluxes into individual components by extending the method of Menzer and McFadden (2017). • Statistical method is proposed to partition CO2 fluxes into gross primary production, ecosystem respiration, anthropogenic emissions from a vehicle and building. • This method uses eddy fluxes and footprint-weighted high-resolution land cover data with temporal subsets that a few components can be negligible. • New partitioning method produces reliable individual components of the urban carbon cycle when compared to inventory data and typical biotic responses to environmental conditions.

Summary: Carbon capture, utilization, and sequestration technologies have been extensively studied to utilize carbon dioxide (CO2), a greenhouse gas, as a resource. So far, however, effective technologies have not been proposed owing to the low efficiency conversion rate and high energy requirements. Here, we present a hybrid Na-CO2 cell that can continuously produce electrical energy and hydrogen through efficient CO2 conversion with stable operation for over 1,000 hr from spontaneous CO2 dissolution in aqueous solution. In addition, this system has the advantage of not regenerating CO2 during charging process, unlike aprotic metal-CO2 cells. This system could serve as a novel CO2 utilization technology and high-value-added electrical energy and hydrogen production device. : Environmental Chemical Engineering; Environmental Science; Energy Materials Subject Areas: Environmental Chemical Engineering, Environmental Science, Energy Materials

In this study, the carburization characteristics of cast and cold-rolled CoCrFeMnNi high-entropy alloys (HEAs) with various grain sizes were investigated. All specimens were prepared by vacuum carburization at 940 °C for 8 h. The carburized/diffused layer was mainly composed of face-centered cubic structures and Cr7C3 carbide precipitates. The carburized/diffused layer of the cold-rolled specimen with a fine grain size (~1 μm) was thicker (~400 μm) than that of the carburized cast specimen (~200 μm) with a coarse grain size (~1.1 mm). In all specimens, the carbides were formed primarily through grain boundaries, and their distribution varied with the grain sizes of the specimens. However, the carbide precipitates of the cast specimen were formed primarily at the grain boundaries and were unequally distributed in the specific grains. Owing to the non-uniform formation of carbides in the carburized cast specimen, the areas in the diffused layer exhibited various carbide densities and hardness distributions. Therefore, to improve the carburization efficiency of equiatomic CoCrFeMnNi HEAs, it is necessary to refine the grain sizes.

Abstract Mutational changes that mostly occur at the head region of hemagglutinin (HA) lead to the emergence of new epidemic influenza viruses, whereas HA antigens have been modified to generate broadly neutralizing antibodies toward highly conserved epitopes in the HA stem. Interestingly, a recent analysis of serum antibody repertoires showed that broadly neutralizing antibodies bind to HA monomer at a conserved region occluded at the intermonomer interface of HA trimer and confer protection in animal models. We showed previously that the recombinant HA ectodomain from a pandemic strain A/Korea/01/2009 was monomeric in solution and crystal structure. In order to examine the potential antigenicity of a monomeric form, we designed HA monomer that incorporates mutations to destabilize trimer conformations. Starting with the HA trimer from a seasonal strain A/Thailand/CU44/2006, mutations were introduced at the intermonomer interface, Ser199 of HA1 and Gly47, Arg75, Phe88, Val91, and Arg106 of HA2. Two mutants, F88E and V91W, were characterized to form a monomer and their double mutant F88E/V91W monomer was selected as an antigen. Animal studies showed that the HA monomer induced protective immunity in vivo, comparable to the trimer, albeit low antibody titers in sera.

Nucleic acid-based regulatory components provide a promising toolbox for constructing synthetic biological circuits due to their design flexibility and seamless integration towards complex systems. In particular, small-transcriptional activating RNA (STAR) and toehold switch as regulators of transcription and translation steps have shown a large library size and a wide dynamic range, meeting the criteria to scale up genetic circuit construction. Still, there are limited attempts to integrate the heterogeneous regulatory components for multilevel regulatory circuits in living cells. In this work, inspired by the design principle of STAR, we designed several switchable transcription terminators starting from natural and synthetic terminators. These switchable terminators could be designed to respond to specific RNA triggers with minimal sequence constraints. When combined with toehold switches, the switchable terminators allow simultaneous control of transcription and translation processes to minimize leakage in Escherichia coli. Further, we demonstrated a set of logic gates implementing 2-input AND circuits and multiplexing capabilities to control two different output proteins. This study shows the potential of novel switchable terminator designs that can be computationally designed and seamlessly integrated with other regulatory components, promising to help scale up the complexity of synthetic gene circuits in living cells.

Synthetic biology brings engineering disciplines to create novel biological systems for biomedical and technological applications. The substantial growth of the synthetic biology field in the past decade is poised to transform biotechnology and medicine. To streamline design processes and facilitate debugging of complex synthetic circuits, cell-free synthetic biology approaches has reached broad research communities both in academia and industry. By recapitulating gene expression systems in vitro, cell-free expression systems offer flexibility to explore beyond the confines of living cells and allow networking of synthetic and natural systems. Here, we review the capabilities of the current cell-free platforms, focusing on nucleic acid-based molecular programs and circuit construction. We survey the recent developments including cell-free transcription–translation platforms, DNA nanostructures and circuits, and novel classes of riboregulators. The links to mathematical models and the prospects of cell-free synthetic biology platforms will also be discussed.

Number lines are acknowledged as an effective model for understanding fractions, yet students often face challenges in interpreting fractions on number lines. This study contributes to the field by investigating students’ performance on fraction number line tasks that require the coordination of their fraction and number line knowledge. To explore this, test items were developed, and 122 fourth-grade students participated in the assessment. Students’ written responses underwent analysis in three phases: a descriptive overview of overall student performance, latent profile analysis to identify subgroups with different competencies, and a qualitative analysis of each latent profile. The findings indicated lower performance among students across the tasks, revealing three distinct latent profiles with different competency characteristics: intuitive, emergent, and advanced understanding of fractions on the number line. From these findings, instructional implications were extrapolated for using number lines as a model for fractions. [ABSTRACT FROM AUTHOR]