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The primary objective in synthetic organic chemistry is to develop highly efficient, selective, and versatile synthetic methodologies, which are essential for discovering new drug candidates and agrochemicals. In this study, we present a unified strategy for a one-pot, catalytic enantioselective synthesis of α-alkyl and α,α′-dialkyl pyrrolidine, piperidine, and indolizidine alkaloids using readily available amides and alkynes. This synthesis is enabled by the identification and development of an Ir/Cu/ N -PINAP catalyzed highly enantioselective and chemoselective reductive alkynylation of α-unbranched aliphatic amides, which serves as the key reaction. This reaction is combined with Pd-catalyzed tandem reactions in a one-pot approach, enabling the collective, catalytic enantioselective total syntheses of eight alkaloids and an anticancer antipode with 90–98% ee . The methodology’s enantio-divergence is exemplified by the one-step access to either enantiomer of alkaloid bgugaine. Saturated α-alkyl aza-heterocycles are found in a wide array of bioactive molecules. Here, the authors disclosed a one-pot, catalytic enantioselective synthesis of pyrrolidine, piperidine and indolizidine alkaloids from amides and alkynes.

Continuous and autonomous system identification is an alternative to regular inspection during operations, which is essential for structural integrity management (SIM) as well as structural health monitoring (SHM). In this regard, online (or real-time) system identification techniques that have recently received considerable attention can be used to assess the current condition and performance during operations and, in the meantime, can be utilized to detect any damage or deterioration. For example, stochastic subspace identification (SSI), based on recursive formulation, has proven its capability in tracking modal parameters as well as time-variant dynamic behaviors. This study proposes the implementation of recursive SSI (RSSI) using the matrix inversion lemma to track slow time-varying parameter changes under ambient excitations. Subsequently, some investigations for practical implementation are examined and discussed. For verifying the reliability of SHM applications based on the proposed methods, two datasets measured from different experiments are exploited to identify the modal parameters reclusively. The results from both numerical simulations and experimental investigations demonstrated the effectiveness of tracking the modal parameters exhibiting time-varying dynamic characteristics under white noise excitations (or ambient excitations).

As a pivotal component in advancing the sustainable development goals (SDGs), structural health monitoring (SHM) has garnered increasing attention in the field of civil engineering. Considering the various approaches, model‐based SHM is the most prevalent and remains highly effective due to its theoretical framework and nondestructive nature, creating a robust framework for effective SHM, enabling early detection of issues, and supporting informed maintenance strategies. Through decades, stochastic subspace identification (SSI) has been proven, and recursive SSI (RSSI) has been consequently applied for model‐based SHM due to its ability to track modal parameters and generate accurate models. However, online validation through structural experiments has yet to be conducted with large‐scale specimens. In this study, a shaking table experiment is conducted to validate the online implementation of RSSI for tracking time‐varying modal parameters in real time. The full‐scale specimen, experimental setup, and test framework are first described with great detail, and a numerical model is developed through a pretest using the shaking table system located in Taiwan. Subsequently, the simulation study provides numerous suggestions for experimental implementation. The experimental study then demonstrates that the proposed approach not only enables an online identification but also produces an accurate dynamic model. Besides, practical measures are recommended to fulfill online processing through the comprehensive simulation and experiential studies, especially those related to the user‐defined parameters and ambient excitations. The results evidence that the SHM systems based on RSSI can effectively track the changes of dynamic characteristics under ambient excitations, ultimately facilitating the assessment and maintenance of structures.

This study uses microbial methods to research the influence of oxygen (O₂) content on the removal efficiency of sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) in a tandem twin-towers desulfurization and denitrification process system. Oxygen can play a significant role in biotrickling towers. Other important factors had already been optimized prior to the study, including inlet concentration, gas flow rate, and temperature. SO₂ and NOₓ were prepared by a chemical method. A gas flow meter was used to regulate nitrogen (N₂) that had been stored in steel cylinders. In this way, the O₂ content was adjusted in the biotrickling towers by controlling the N₂ flow rate. Five gradients of O₂ content were selected for investigation, namely 4, 8, 12, 16, and 20%. Results indicated that the SO₂ removal efficiency from mixed gas (SO₂ and NOₓ) can reach 100%, from all of the five O₂ gradients, in biotrickling towers. In a tandem twin-towers desulfurization and denitrification process system, the NOₓ removal efficiency and the inlet concentration of nitrogen dioxide (NO₂) gradually increased as the O₂ content increased. Specifically, the average removal efficiency of NOₓ increased from 49.28 to 80.85% as the O₂ content changed from 4 to 20%. The oxygen levels influenced the removal of NOₓ but the SO₂ removal efficiency in mixed gas was always stable.

It has been suggested that archaea carrying the accA gene, encoding the alpha subunit of the acetyl CoA carboxylase, autotrophically fix CO 2 using the 3-hydroxypropionate/4-hydroxybutyrate pathway in low-temperature environments (e.g., soils, oceans). However, little new information has come to light regarding the occurrence of archaeal accA genes in high-temperature ecosystems. In this study, we investigated the abundance and diversity of archaeal accA gene in hot springs in Yunnan Province, China, using DNA- and RNA-based phylogenetic analyses and quantitative polymerase chain reaction. The results showed that archaeal accA genes were present and expressed in the investigated Yunnan hot springs with a wide range of temperatures (66–96 °C) and pH (4.3–9.0). The majority of the amplified archaeal accA gene sequences were affiliated with the ThAOA/HWCG III [thermophilic ammonia-oxidizing archaea (AOA)/hot water crenarchaeotic group III]. The archaeal accA gene abundance was very close to that of AOA amoA gene, encoding the alpha subunit of ammonia monooxygenase. These data suggest that AOA in terrestrial hot springs might acquire energy from ammonia oxidation coupled with CO 2 fixation using the 3-hydroxypropionate/4-hydroxybutyrate pathway.

The paper summarizes the technology development status of ore crushing and grinding from many angles, and analyzes the future development trend. The development of mineral processing automation at home and abroad are introduced, and points out the new progress of particle size analyzer and grade analyzer and other important mineral analysis instruments.

Sepsis-associated encephalopathy is a common neurological complication of sepsis and is responsible for higher mortality and poorer long-term outcomes in septic patients. Sepsis-associated encephalopathy symptoms can range from mild delirium to deep coma, which occurs in up to 70% of patients in intensive care units. The pathological changes in the brain associated with sepsis include cerebral ischaemia, cerebral haemorrhage, abscess and progressive multifocal necrotic leukoencephalopathy. Several mechanisms are involved in the pathogenesis of sepsis-associated encephalopathy, such as blood–brain barrier dysfunction, cerebral blood flow impairment, glial cell activation, leukocyte transmigration, and neurotransmitter disturbances. These events are interrelated and influence each other, therefore they do not act as independent factors. This review is focused on new evidence showing the pathological process of sepsis-associated encephalopathy.

Crocodilians are diving reptiles that can hold their breath under water for long periods of time and are crepuscular animals with excellent sensory abilities. They comprise a sister lineage of birds and have no sex chromosome. Here we report the genome sequence of the endangered Chinese alligator （Alligator sinensis） and describe its unique features. The next-generation sequencing generated 314 Gb of raw sequence, yielding a genome size of 2.3 Gb. A total of 22 200 genes were predicted in Alligator sinensis using a de novo, homology- and RNA-based combined model. The genetic basis of long-diving behavior includes duplication of the bicarbonate-binding hemoglobin gene, co-function- ing of routine phosphate-binding and special bicarbonate-binding oxygen transport, and positively selected energy metabolism, ammonium bicarbonate excretion and cardiac muscle contraction. Further, we elucidated the robust Alligator sinensis sensory system, including a significantly expanded olfactory receptor repertoire, rapidly evolving nerve-related cellular components and visual perception, and positive selection of the night vision-related opsin and sound detection-associated otopetrin. We also discovered a well-developed immune system with a considerable num- ber of lineage-specific antigen-presentation genes for adaptive immunity as well as expansion of the tripartite motif- containing C-type lectin and butyrophilin genes for innate immunity and expression of antibacterial peptides. Mul- tifluorescence in situ hybridization showed that alligator chromosome 3, which encodes DMRT1, exhibits significant synteny with chicken chromosome Z. Finally, population history analysis indicated population admixture 0.60-1.05 million years ago, when the Qinghai-Tibetan Plateau was uplifted.