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Objective: This study aimed to optimize the performance of heat pump system and discuss the optimal exhaust pressure of carbon dioxide system under the control of different working conditions. Methods: By establishing a CO2 trans-critical heat pump model, the relationship between exhaust pressure and heat production, inspiratory superheat, refrigerant mass flow rate and system energy efficiency was analyzed, and the influence of inlet and outlet water temperature and ambient temperature on the optimal exhaust pressure was deeply studied. Moreover, the reliability of the model was verified by the CO2 heat pump test bench. Results: At the three effluent temperatures, the heat production increased with the increase of exhaust pressure, and the mass flow rate decreased with the increase of exhaust pressure. The cycle performance coefficient and superheat showed a trend of first increasing and then decreasing with the increase of exhaust pressure, the optimal exhaust pressure increased with the increase of inlet and outlet water temperature and ambient temperature, but the increase of inlet and outlet water temperature reduced the system cycle performance coefficient. Based on this, the optimal exhaust pressure correlation formula at the outlet temperature of 60 ℃ was fitted, and five groups of tests were designed to prove its reliability. Conclusion: The optimal exhaust pressure of the system is determined by a large number of simulation data, and compared with the test values, it is found that the error values are less than 5%, which meets the test and design requirements.

Supramolecular polymers are typical self-assemblies, in which repeating monomer units are bonded together with dynamic and reversible noncovalent interactions. Supramolecular polymers can combine the advantages of polymer science and supramolecular chemistry. Aggregation-induced emission (AIE) means that a molecule remains faintly emissive in the dispersed state but intensively luminescent in a highly aggregated state. AIE has brought new opportunities and further development potential to the field of polymeric chemistry. The integration of AIE luminogens with supramolecular interactions can provide new vitality for supramolecular polymers. Therefore, it is essential for scientists to understand the preparation and applications of AIE-active supramolecular polymers. This review focuses on the recent advanced progress in the preparation of AIE-active supramolecular polymers. In addition, we summarize the newly developed supramolecular polymers with an AIE nature and their applications in chemical sensing, and in vitro and in vivo imaging, as well as the visualization of their structure and properties. Finally, the development trends and challenges of AIE-active supramolecular polymers are prospected. [ABSTRACT FROM AUTHOR]

Despite progress in cancer immunotherapy, ovarian cancer (OC) prognosis continues to be disappointing. Recent studies have shed light on how not just tumour cells, but also the complex tumour microenvironment, contribute to this unfavourable outcome of OC immunotherapy. The complexities of the immune microenvironment categorize OC as a 'cold tumour'. Nonetheless, understanding the precise mechanisms through which the microenvironment influences the effectiveness of OC immunotherapy remains an ongoing scientific endeavour. This review primarily aims to dissect the inherent characteristics and behaviours of diverse cells within the immune microenvironment, along with an exploration into its reprogramming and metabolic changes. It is expected that these insights will elucidate the operational dynamics of the immune microenvironment in OC and lay a theoretical groundwork for improving the efficacy of immunotherapy in OC management. [ABSTRACT FROM AUTHOR]

Four pillar-layered AIEgen-based MOFs exhibit higher thermal stability, tunable emission colors and improved QYs compared with that of non-pillar-layered AIEgen-based MOFs by confining the AIE ligands into layers. These results reveal that rationally manipulating AIE ligands into layers of pillar-layered MOFs is an effective strategy for the design and construction of tunable luminescent MOF systems. [ABSTRACT FROM AUTHOR]

Tribological properties of oleic acid modified natural serpentine ultrafine mineral powders as lubricating oil additive were investigated by a reciprocating sliding wear tester. The effects of the four factors including load, reciprocating frequency, sliding time and concentration of serpentine on the properties of serpentine additive were analyzed. Results indicate that the anti-wear and friction-reducing properties of the base oil are significantly improved by the addition of the modified serpentine powders. The order that affects the friction-reducing performance of the serpentine additive is:concentration, reciprocating frequency, load, sliding time, and the optimal tribological conditions are 100 N, 5 Hz, 180 min, 0.5%(mass fraction). While that affects the anti-wear property is:load, concentration, reciprocating frequency, sliding time, and the optimal conditions are 100 N, 50 Hz, 180 min, 0.3%. Serpentine minerals forms a tribofilm consisting of various oxides, graphite and organic compounds on the friction surface, which is the key to improving anti-wear and friction-reducing properties.

BACKGROUND: Despite the advancement of new screening strategies and the advances in pharmacological therapies, the cancerization rates of familial adenomatous polyposis (FAP) are stable and even increased in the last years. Therefore, it necessitates additional research to characterize and understand the underlying mechanisms of FAP. OBJECTIVE: To determine the genes that drive the pathogenesis of familial adenomatous polyposis (FAP). METHODS: We performed on a cohort (GSE111156) gene profile, which consist of four group of gene expressions (the gene expressions of cancer, adenoma and normal tissue of duodenal cancer from patients with FAP were defined as Case N, Case A and Case C respectively, while that of adenoma tissue from patients with FAP who did not have duodenal cancer was Ctrl A). Tracking Tumor Immunophenotype (TIP) website was applied to reveal immune infiltration profile and signature genes of FAP. We merged the genes of key module (pink and midnight module) with signature genes to obtained the biomarkers related with FAP pathogenesis. The expression of these five biomarkers in FAP intratumoral region (IT) and tumor rim (TR) was detected with Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). RESULTS: In total, 220, 23 and 63 DEGs were determined in Cases C, A and N, in comparison to Ctrl A. In total, 196 and 10 DEGs were determined in Cases C and A, separately, as compared to Case N. A total of four biomarkers including CCL5, CD3G, CD2 and TLR3 were finally identified associated with pink module, while only one biomarker (KLF2) associated with midnight module was identified. All biomarkers were evidently raised in FAP IT tissues utilizing qRT-PCR. CONCLUSION: We identified five potential biomarkers for pathogenesis of FAP to understand the fundamental mechanisms of FAP progression and revealed some probable targets for the diagnosis or treatment of FAP. [ABSTRACT FROM AUTHOR]

A new electrochemical transformation is presented that enables chemists to couple simple alkyl carboxylic acid derivatives with an electrophilic amine reagent to construct C(sp3)−N bond. The success of this reaction hinges on the merging of cooperative electrochemical reduction with nickel catalysis. The chemistry exhibits a high degree of practicality, showcasing its wide applicability with 1°, 2°, 3° carboxylic acids and remarkable compatibility with diverse functional groups, even in the realm of late‐stage functionalization. Furthermore, extensive mechanistic studies have unveiled the engagement of alkyl radicals and iminyl radicals; and elucidated the multifaceted roles played by iPr2O, Ni catalyst, and electricity. [ABSTRACT FROM AUTHOR]

Basic helix-loop-helix (bHLH) proteins are highly conserved DNA-binding transcription factors of a large superfamily. Animal bHLH proteins play important regulatory roles in various developmental processes such as neurogenesis, myogenesis, heart development, and hematopoiesis. The jewel wasp (Nasonia vitripennis) is a good model organism of hymenoptera insects for studies of developmental and evolutionary genetics. In this study, we identified 48 bHLH genes in the genome of N. vitripennis. According to phylogenetic analysis, based on N. vitripennis bHLH (NvbHLH) motif sequences and structural domain distribution in their full-length protein sequences, the identified NvbHLH genes were classified into 36 bHLH families with 19,12, 9,1, 6, and 1 member(s) in groups A, B, C, D, E, and F, respectively. Our classification to the identified NvbHLH family members confirms GenBank annotations for 21 of the 48 NvbHLH proteins and provides useful information for further characterization and annotation of the remaining 27 NvbHLH proteins. Compared to other insect species, N. vitripennis has the lowest number of bHLH family members. No NvbHLH members have been found in the families Net, MyoRa, and PTFa, while all other insect species have at least one member in each of the families. These data constitute a solid basis for further investigations into the functions of bHLH proteins in developmental regulation of N. vitripennis. Key words: basic helix-loop-helix, phylogenetic analysis, ortholog, BLAST search, Nasonia vitripennis. Les proteines a motif basique helice-boucle-helice (bHLH) sont des facteurs de transcription tres hautement conserves qui forment une grande superfamille. Les proteines bHLH animales jouent d'importants roles dans la regulation de divers processus du developpement comme la neurogenese, la myogenese, le developpement cardiaque et l'hematopoiese. La guepe parasite Nasonia vitripennis est un bon organisme modele chez les hymenopteres pour des etudes en genetique du developpement et de revolution. Dans ce travail, les auteurs ont identifie 48 genes codant pour des bHLH au sein du genome du N. vitripennis. Des analyses phylogenetiques basees sur les motifs de sequence et la distribution des domaines structuraux au sein des regions codantes des bHLH du N. vitripennis (NvbHLH), les genes NvbHLH ainsi identifies ont ete classes au sein de 36 familles NvbHLH avec 19,12, 9,1, 6 et 1 membre(s) au sein des groupes A, B, C, D, E et F respectivement. Ces classifications des proteines NvbHLHs au sein de ces familles confirment les annotations GenBank pour 21 de ces 48 proteines et fournissent de l'information utile en vue d'une caracterisation plus avancee et de l'annotation des 27 autres proteines NvbHLH. Compare a d'autres especes d'insectes, le N. vitripennis compte le plus faible nombre de membres de la famille des bHLH. Aucune proteine NvbHLH n'a ete trouvee au sein des familles Net, MyoRa et PTFa, tandis que toutes les autres especes d'insectes comptent au moins un membre au sein de chacune de ces familles. Ces donnees constituent une assise solide pour de futures etudes des fonctions des proteines bHLH dans la regulation du developpement chez le N. vitripennis. [Traduit par la Redaction] Mots-cles: motif basique helice-boucle-helice, analyse phylogenetique, orthologue, interrogation BLAST, Nasonia vitripennis., Introduction Basic helix-loop-helix (bHLH) transcription factors are important regulatory proteins in various eukaryotic developmental processes such as neurogenesis, myogenesis, sex determination, and environmental response. Along with the identification and classification [...]

Thermally activated delayed fluorescence (TADF) was achieved when electron-rich triphenylene (Tpl) donors were confined to a cage-based porous metal-organic framework (MOF) host (NKU-111) composed of electron-deficient 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine (Tpt) acceptor as the ligand. The spatially separated donor and acceptor molecules in a face-to-face stacking pattern generated strong through-space charge transfer (CT) interactions with a small energy splitting between the singlet and triplet excited states (∼0.1 eV), which enabled TADF. The resulting Tpl@NKU-111 exhibited an uncommon enhanced emission intensity as the temperature increased. Extensive steady-state and time-resolved spectroscopic measurements and first-principles simulations revealed the chemical and electronic structure of this compound in both the ground and low-lying excited states. A double-channel (T1, T2) intersystem crossing mechanism with S1 was found and explained as single-directional CT from the degenerate HOMO−1/HOMO of the guest donor to the LUMO+1 of one of the nearest acceptors. The rigid skeleton of the compound and effective through-space CT enhanced the photoluminescence quantum yield (PLQY). A maximum PLQY of 57.36% was achieved by optimizing the Tpl loading ratio in the host framework. These results indicate the potential of the MOFs for the targeted construction and optimization of TADF materials. [ABSTRACT FROM AUTHOR]