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Twin-field (TF) quantum key distribution (QKD) has rapidly risen as the most viable solution to long-distance secure fibre communication thanks to its fundamentally repeater-like rate-loss scaling. However, its implementation complexity, if not successfully addressed, could impede or even prevent its advance into real-world. To satisfy its requirement for twin-field coherence, all present setups adopted essentially a gigantic, resource-inefficient interferometer structure that lacks scalability that mature QKD systems provide with simplex quantum links. Here we introduce a technique that can stabilise an open channel without using a closed interferometer and has general applicability to phase-sensitive quantum communications. Using locally generated frequency combs to establish mutual coherence, we develop a simple and versatile TF-QKD setup that does not need service fibre and can operate over links of 100 km asymmetry. We confirm the setup’s repeater-like behaviour and obtain a finite-size rate of 0.32 bit/s at a distance of 615.6 km. Twin-field QKD should allow secure quantum communication with favourable rate-loss scaling, but requires interferometric implementations which are often impractical for long distances. Here, the authors show how to realise it without the need for closed interferometers.

Objective This review explores recent advancements in anesthesia care, focusing on the integration of innovative practices to enhance patient outcomes across the perioperative period. Methods Following the framework of Whitmore and Knafl, we systematically searched six databases (PubMed, Google Scholar, EMBASE, CINAHL, OVID, and Cochrane Library) for studies published from January 2020 to January 2024, relating to advancements in anesthesia care, best practice implementation, and patient outcomes. After independent screening and data extraction by two reviewers, the review focuses on innovations in anesthetic drugs, monitoring technologies, anesthesia techniques, and evidence-based practices in anesthesia and clinical guidelines. Results Of the 25,984 studies retrieved, 26 met inclusion criteria. Recent developments in anesthetic drugs have improved safety and efficacy, reducing complications. Advanced monitoring devices, such as multiparameter and brain function monitors, have enhanced patient safety through real-time assessments. Innovations in regional anesthesia and ultrasound-guided nerve blocks have led to better pain management, reduced recovery time, and minimized morbidity. Additionally, evidence-based practices like comprehensive preoperative assessment, patient education, and multidisciplinary teamwork significantly improved patient outcomes. Conclusion Integrating the latest innovations and best practices in anesthesia care is essential for optimizing patient outcomes. Ongoing research and adoption of advanced technologies are crucial to addressing current challenges and enhancing anesthesia quality. This review emphasizes the importance of a holistic approach from preoperative preparation to postoperative recovery to achieve optimal patient outcomes.

The use of halogen bond is widespread in drug discovery, design, and clinical trials, but is overlooked in drug biosynthesis. Here, the role of halogen bond in the nitrilase-catalyzed synthesis of ortho-, meta-, and para-chlorophenylacetic acid was investigated. Different distributions of halogen bond induced changes of substrate binding conformation and affected substrate selectivity. By engineering the halogen interaction, the substrate selectivity of the enzyme changed, with the implication that halogen bond plays an important role in biosynthesis and should be used as an efficient and reliable tool in enzymatic drug synthesis.

Cerebrovascular abnormalities are critical indicators of stroke and neurodegenerative diseases like Alzheimer’s disease (AD). Understanding the normal evolution of brain vessels is essential for detecting early deviations and enabling timely interventions. Here, for the first time, we proposed a pipeline exploring the joint evolution of cortical volumes (CVs) and arterial volumes (AVs) in a large cohort of 2841 individuals. Using advanced deep learning for vessel segmentation, we built normative models of CVs and AVs across spatially hierarchical brain regions. We found that while AVs generally decline with age, distinct trends appear in regions like the circle of Willis. Comparing healthy individuals with those affected by AD or stroke, we identified significant reductions in both CVs and AVs, wherein patients with AD showing the most severe impact. Our findings reveal gender-specific effects and provide critical insights into how these conditions alter brain structure, potentially guiding future clinical assessments and interventions. Cerebrovascular abnormalities are key indicators of stroke and neurodegenerative diseases. Here, the authors show evolutionary trends of cortical and vascular volumes across spatial hierarchies with a deep learning-based pipeline and varying volume reductions in different brain pathologies.

Background d -Xylonic acid is a versatile platform chemical with broad potential applications as a water reducer and disperser for cement and as a precursor for 1,4-butanediol and 1,2,4-tributantriol. Microbial production of d -xylonic acid with bacteria such as Gluconobacter oxydans from inexpensive lignocellulosic feedstock is generally regarded as one of the most promising and cost-effective methods for industrial production. However, high substrate concentrations and hydrolysate inhibitors reduce xylonic acid productivity. Results The d -xylonic acid productivity of G. oxydans DSM2003 was improved by overexpressing the mGDH gene, which encodes membrane-bound glucose dehydrogenase. Using the mutated plasmids based on pBBR1MCS-5 in our previous work, the recombinant strain G. oxydans /pBBR-R3510-mGDH was obtained with a significant improvement in d -xylonic acid production and a strengthened tolerance to hydrolysate inhibitors. The fed-batch biotransformation of d -xylose by this recombinant strain reached a high titer (588.7 g/L), yield (99.4%), and volumetric productivity (8.66 g/L/h). Moreover, up to 246.4 g/L d -xylonic acid was produced directly from corn stover hydrolysate without detoxification at a yield of 98.9% and volumetric productivity of 11.2 g/L/h. In addition, G. oxydans /pBBR-R3510-mGDH exhibited a strong tolerance to typical inhibitors, i.e., formic acid, furfural, and 5-hydroxymethylfurfural. Conclusion Through overexpressing mgdh in G. oxydans , we obtained the recombinant strain G. oxydans /pBBR-R3510-mGDH, and it was capable of efficiently producing xylonic acid from corn stover hydrolysate under high inhibitor concentrations. The high d -xylonic acid productivity of G. oxydans /pBBR-R3510-mGDH made it an attractive choice for biotechnological production.

Understanding intercity linkage patterns is of great importance to understanding urbanization. With advancements in transportation, communication technology, and the availability of big data, the “death of distance” concept has gained significant attention. This paper analyzes the asymmetric spatial intercity linkage network in China’s economically developed YRDR based on big data derived from Spring Festival (SF) migration. The aim is to explore the determinants of these linkages considering multivariate distance factors. The findings indicate a notable pattern of asymmetry in the intercity linkage network of the YRDR between core and non-core cities. The spatial decay effect of geographic distance on intercity asymmetry linkage is observed. Despite technological advancements, geographic distance remains the most influential and decisive factor in determining intercity asymmetric linkages. While other attribute distances also play a positive role, their effects become complex when controlling for geographic distance. Understanding these attribute distances is essential in comprehending the decay effect. This study contributes to the empirical investigation of the “death of distance” debate and provides a practical analytical framework for analyzing the drivers of intercity linkage patterns. It enhances our understanding of intercity spatial linkages within the context of urbanization in China and offers valuable insights for formulating development policies in the YRDR.

Summary Bioproduction of optical pure (R)‐citronellal from (E/Z)‐citral at high substrate loading remains challenging. Low catalytic efficiency of (R)‐stereoselective ene reductases towards crude citral mixture is one of the major bottlenecks. Herein, a structure‐based engineering strategy was adopted to enhance the catalytic efficiency and stereoselectivity of an ene reductase (OYE2p) from Saccharomyces cerevisiae YJM1341 towards (E/Z)‐citral. On basis of homologous modelling, molecular docking analysis and alanine scanning at the binding pocket of OYE2p, a mutant Y84A was obtained with simultaneous increase in catalytic efficiency and stereoselectivity. Furthermore, site‐saturation mutagenesis of Y84 yielded seven mutants with improved activity and stereoselectivity in the (E/Z)‐citral reduction. Among them, the variant Y84V exhibited an 18.3% and 71.3% rise in catalytic efficiency (kcat/Km) for (Z)‐citral and (E)‐citral respectively. Meanwhile, the stereoselectivity of Y84V was improved from 89.2% to 98.0% in the reduction in (E/Z)‐citral. The docking analysis and molecular dynamics simulation of OYE2p and its variants revealed that the substitution Y84V enabled (E)‐citral and (Z)‐citral to bind with a smaller distance to the key hydrogen donors at a modified (R)‐selective binding mode. The variant Y84V was then co‐expressed with glucose dehydrogenase from Bacillus megaterium in E. coli D4, in which competing prim‐alcohol dehydrogenase genes were deleted to prevent the undesired reduction in the aldehyde moiety of citral and citronellal. Employing this biocatalyst, 106 g l−1 (E/Z)‐citral was completely converted into (R)‐citronellal with 95.4% ee value and a high space‐time yield of 121.6 g l−1 day−1. The work highlights the synthetic potential of Y84V, which enabled the highest productivity of (R)‐citronellal from (E/Z)‐citral in high enantiopurity so far. This study aims to design and engineering of whole‐cell biocatalyst for efficient production of (R)‐citronellal on a gram scale. We report an attractive engineered ene reductase through structure‐based engineering with increased catalytic efficiency and high stereoselectivity (R, 98.0% ee) toward (E/Z)‐citral. By co‐expressing the variant Y84V and BmGDH in the engineered E. coli BL21(DE3) with reduced aldehyde reduction, a whole‐cell biocatalyst was tailored for the preparative synthesis of (R)‐citronellal with 95.4% ee and 121.6 g l−1 day−1 space‐time yield, and opening the possibility of employing microbial catalyst in the C=C bond reduction of α,β‐unsaturated aldehydes.

Abdominal aortic aneurysms (AAAs) are characterized by localized dilation of the abdominal aorta. They are associated with several serious consequences, including compression of adjacent abdominal organs, pain, treatment-related financial expenditure. The main complication of AAA is aortic rupture, which is responsible for about 200,000 deaths per year worldwide. An increasing number of researchers are dedicating their efforts to study AAA, resulting in significant progress in this field. Despite the commendable progress made thus far, there remains a lack of established methods to effectively decelerate the dilation of aneurysms. Therefore, further studies are imperative to expand our understanding and enhance our knowledge concerning AAAs. Although numerous factors are known to be associated with the occurrence and progression of AAA, the exact pathway of development remains unclear. While asymptomatic at most times, AAA features a highly unpredictable disease course, which could culminate in the highly deadly rupture of the aneurysmal aorta. Current guidelines recommend watchful waiting and lifestyle adjustment for smaller, slow-growing aneurysms, while elective/prophylactic surgical repairs including open repair and endovascular aneurysm repair are recommended for larger aneurysms that have grown beyond certain thresholds (55 mm for males and 50 mm for females). The latter is a minimally invasive procedure and is widely believed to be suited for patients with a poor general condition. However, several concerns have recently been raised regarding the postoperative complications and possible loss of associated survival benefits on it. In this review, we aimed to highlight the current status of diagnosis and treatment of AAA by an in-depth analysis of the findings from literatures.

Population mobility patterns are an important reflection of the future distribution of migrant populations and the evolution trends of urbanization patterns. However, although research based on statistical data can reveal the pattern of population flow, it also shows a time lag. Most of the population flow network research based on location services data has failed to fully discuss the symmetry of directional outflows and inflows in the same place and the two-way symmetrical connections between places. This paper creatively proposes and constructs the concept and analysis framework of population flow asymmetry. We used the Yangtze River Delta (YRD) as a typical case and the results of our analysis reveal the temporal and spatial asymmetry of the population flow using complex network analysis methods based on the Spring Festival (SF) population migration big data. We found that the timing asymmetry manifested in such a way that the closer it was to the festival, the greater the scale and intensity of the population movement. This is a feature of the lack of scale and regional differences within China. The spatial asymmetry was manifested in three aspects, network, node, and link, and the core cities with administrative and economic hierarchical advantages dominated the asymmetric pattern of regional population mobility. In addition, distance and administrative boundaries are factors that cannot be ignored in population movements, and they were implicated in the degree of asymmetry by distance enhancement and administrative boundary blocking. The conclusions of this study can not only provide policy decision-making guidelines for population management and resource allocation in the YRD, but they can also provide a reference value for achieving the goal of regional, high-quality, integrated development. Future research will further the discussion and management of socio-economic attributes in order to develop a more detailed and microscopic understanding of the mechanisms of population mobility patterns.