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Two L-phenylalanine derivatives with 5,8-bis(2-(carbazol-3-yl)vinyl)quinoxaline ( PCQ) and 5,8-bis[2-(carbazol-3-yl)]-2,3-dimethylquinoxaline ( DCQ) as fluorophores were synthesized, and their photophysical properties were measured and compared. The two compounds were found to gelate some organic solvents and self-assemble into 1D nanofibers in gels. The wet gel of PCQ emitted a weak orange fluorescence, but the DCQ gel had a strong green one. This result can be due to the presence of two methyl groups and the nonplanar conformation of fluorophore in DCQ. The gel film of DCQ also showed significantly stronger fluorescence than that of PCQ. Thus, the wet gel and xerogel film of DCQ were selected to study their sensing properties to acids. The yellow wet gel of DCQ transformed into a brown sol upon the addition of 0.2 equiv trifluoroacetic acid (TFA), accompanied by emission quenching. The xerogel film of DCQ rapidly responded to volatile acids, such as TFA, HCl, and HOAc. The fluorescence of the xerogel film was gradually quenched with increased concentration of volatile acid vapors. The fibrous film exhibited low detection limits for volatile acid. The detection limits of the thin films for TFA, HCl, and HOAc reached 43, 122, and 950 ppb, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Proposing an approach for high-performance solid DATNBI via rapid phase transition. • Obtaining a series of α-DATNBI with various morphologies by in-situ rapid preparation. • Proving a three-phase transition mechanism between solution, solvate, and target form. Using energetic materials (EMs) products with impure solid forms in practical application scenarios will lead to a series of serious consequences in terms of safety, mechanics, storage, detonation, and reliability properties. A novel approach to obtain the scarce and superior performance solid form of EMs was developed by the strategy of rapid in-situ solvate-mediated phase transformation, which is a promising and convenient method because of avoiding additional desolvating under specific external conditions and greatly reducing the risks in the production of EMs. In this strategy, the low sensitivity and highly energetic material 4,4′,5,5′-tetranitro-1 H ,1′ H -[2,2′-biimidazole]-1,1′-diamine (DATNBI) was used as a model substance and its α-DATNBI that is hard to gain but with better performance was successfully prepared. Furthermore, a mechanism of this solvate-mediated method was studied by exploring the types of solute clusters and intermolecular interaction of DATNBI in the microscopic view. These molecular assembly modes were determined in solid and solvents employing X-ray diffraction and in-situ micro-Raman technique, as well as attenuated total reflectance-Fourier transform infrared spectra combined with density functional theory calculation, respectively. It is found that solute molecules tend to exist as solvated monomers resulting in the prior precipitation of solvate in saturated solution of tetrahydrofuran (THF). From the perspective of crystal structure and transformation energy, the solvates consisting of DATNBI and THF can easily transform to the scarce α form of DATNBI. This study proposes a new practical strategy for a specific solid form mediated by solvates-mediated phase transformation, which is particularly beneficial for the preparation of high-purity solid forms of EMs with better energy and safety properties but also helps us to understand the key role of solvates in the polymorph formation.. [ABSTRACT FROM AUTHOR]

Purpose: The genomic characteristics of uterine sarcomas have not been fully elucidated. This study aimed to explore the genomic landscape of the USs., Materials and Methods: Comprehensive genomic analysis through RNA-sequencing was conducted. Gene fusion, differentially expressed genes (DEGs), signaling pathway enrichment, immune cell infiltration, and prognosis were analyzed. A deep learning model was constructed to predict the survival of US patients., Results: A total of 71 US samples were examined, including 47 endometrial stromal sarcomas (ESS), 18 uterine leiomyosarcomas (uLMS), 3 adenosarcomas, 2 carcinosarcomas, and 1 uterine tumor resembling an ovarian sex-cord tumor (UTROSCT). ESS (including high-grade ESS and low-grade ESS) and uLMS showed distinct gene fusion signatures; a novel gene fusion site, MRPS18A - PDC-AS1 could be a potential diagnostic marker for the pathology differential diagnosis of uLMS and ESS; 797 and 477 uDEGs were identified in the ESS vs. uLMS and HGESS vs. LGESS groups, respectively. The uDEGs were enriched in multiple pathways. Fifteen genes including LAMB4 were confirmed with prognostic value in USs; immune infiltration analysis revealed the prognositic value of myeloid dendritic cells, plasmacytoid dendritic cells, natural killer cells, macrophage M1, monocytes and hematopoietic stem cells in USs; the deep learning model named MMN-MIL showed satisfactory performance in predicting the survival of US patients, with the area under the receiver operating curve curve reached 0.909 and accuracy achieved 0.804., Conclusion: USs harbored distinct gene fusion characteristics and gene expression features between HGESS, LGESS, and uLMS. The MMN-MIL model could effectively predict the survival of US patients.

Background: Capsule-preserving hydrodilatation is a common treatment for adhesive capsulitis (AC), and ultrasound (US) has recently become the most popular adjuvant tool for image-guided glenohumeral joint injection. However, traditional US is hardly adequate to assess extracapsular fluid leakage, which may decide the treatment outcomes. In this study, we explored the value of contrast-enhanced ultrasound (CEUS) guided capsule-preserving hydrodilatation with steroids and ultrasonic contrast agents for treatment of AC., Methods: A total of 40 consecutive patients with AC were prospectively enrolled and received CEUS-guided capsule-preserving hydrodilatation. The number of injection attempts, injection volume, and fluid leakage were recorded, and the correlations with clinical features were analyzed by Pearson or Spearman correlation coefficients. Outcome measures including visual analog scale (VAS) score, passive range of motion (ROM), and shoulder pain and disability index (SPADI) score were evaluated at baseline and 4 weeks after treatment. Comparisons between patients with good and poor clinical outcomes were performed with independent t -test, Mann-Whitney U test, and chi-square test. Logistic regression was used to identify predictors of good clinical outcomes. A P value <0.05 defined significance., Results: Access to the glenohumeral joint was successful in 87.5% patients on the first attempt. The infused fluid volume was 21.0±3.40 mL. Longer symptom duration (r=-0.676, P<0.001), greater SPADI (r=-0.148, P=0.007), and decreased ROM in abduction (r=0.38, P=0.016) were associated with a decreased volume of infused fluid. CEUS detected massive fluid leakage in 5 (12.5%) patients, with 4 capsule ruptures confirmed by magnetic resonance imaging (MRI). Longer symptom duration (r=0.485, P=0.001), decreased ROM in the direction of abduction (r=-0.33, P=0.037), and external rotation (r=-0.34, P=0.032) were correlated with an increased incidence of massive fluid leakage. Moreover, patients with good outcomes had significantly shorter symptom duration (5.7±2.09 vs . 11.2±3.89 months, P=0.002) and greater initial VAS score (6.9±1.04 vs . 6.3±0.50, P=0.022) than those with poor outcomes. Absence of massive fluid leakage was an independent predictor of clinical good outcomes at 4 weeks after treatment [odd ratio (OR) =0.05, 95% confidential interval (CI): 0.003-0.882, P=0.041]., Conclusions: CEUS-guided capsule-preserving hydrodilatation allows real-time visualization of capsule dilatation, accurate detection of extracapsular fluid leakage, and identification of risks for capsule rupture. It provides an effective treatment for AC, and is useful to predict patients' clinical outcomes., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-39/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

In this work, we experimentally perform time delay interferometry by using a transfer oscillator, which is capable of reducing the laser frequency noise and the clock noise simultaneously in the post processing. The iodine frequency reference is coherently downconverted to the microwave frequency using a laser frequency comb. The residual noise of the downconversion network is 5 × 10 -6 Hz/Hz 1/2 at 0.7 mHz, and 4 × 10 -6 Hz/Hz 1/2 at 0.1 Hz, indicating high homology between the optical frequency and the microwave frequency. We carry out time delay interferometry with the aid of the electrical delay module, which can introduce large time delays. The results show that the laser frequency noise and the clock noise can be reduced simultaneously by ten and three orders of magnitude, respectively, in the frequency band from 0.1 mHz to 0.1 Hz. The performance of the noise reduction can reach 6 × 10 -8 Hz/Hz 1/2 at 0.1 mHz, and 7 × 10 -7 Hz/Hz 1/2 at 1 mHz, meeting the requirements of the space-borne gravitational wave detection. Our work will be able to offer an alternative method for the frequency comb-based time delay interferometry in the future space-borne gravitational wave detectors.

Thermal comfort and environmental health in scenic open spaces, a communication bridge between tourists and their environment, are prerequisites for tourism activities. In this study, scenic open spaces in an urban area of Xi'an, China were selected. Thermal perception (thermal sensation, comfort and acceptability) of residents and tourists were investigated through meteorological measurement and questionnaire survey. Physiological equivalent temperature (PET) was used to determine thermal benchmarks of all visitors to the site. Variables that influence individual thermal perception assessment (physical, individual, society and psychology) were measured and compared. Finally, a series of strategies and suggestions were proposed based on meteorological characteristics and influencing factors of thermal perception from perspectives of designers and scenic spot managers. Results show that: 1) Neutral PET (NPET) of respondents were 17.3 °C (residents) and 15.5 °C (tourists). Neutral PET ranges (NPETR) were 8.9-25.8 °C (residents) and 7.2-23.8 °C (tourists). Preferred PET values were 20.1 °C (residents) and 19.7 °C (tourists). Thermal acceptability ranges (TAR) were 6.3-37.8 °C (residents) and 0.5-39.9 °C (tourists). 2) In winter, physical factors were primary influencers of residents' thermal perception, followed by social factors, while tourists' thermal perception was mainly influenced by physical factors. In spring, physical factors were still the primary influencers for residents, followed by individual factors. Physical factors were also dominant for tourists, followed by psychological. In summer, physical factors were the major influencing factors for residents and tourists' thermal perceptions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objective: To investigate the characteristics of gut microbiota dysbosis in patients with severe pneumonia using 16SrDNA sequencing., Methods: A prospective observational research was conducted. The stool samples retained by natural defecation or enema within 2 days after hospital were collected from 16 patients with severe pneumonia admitted to department of intensive care unit (ICU) of General Hospital of Ningxia Medical University from June to December in 2018 and 10 persons for physical exam were enrolled as the healthy control group. The 16SrDNA sequencing technology was used to detect fecal flora and analyze biological information., Results: (1) 1 015 475 effective sequences were obtained from the stool samples from the severe pneumonia group and the healthy control group. Using 16SrDNA method, it was found that the average effective length of the sample sequence was 458.35 bp and the average sequence number of the total samples was 39 056.73. (2) Analysis of α diversity of gut microbiota showed that, compared with the healthy control group, the Ace index, Chao index and the Shannon index of gut microbiota diversity in the severe pneumonia group were significantly decreased [Ace index: 167.23 (143.14, 211.26) vs. 227.71 (214.53, 247.05), Chao index: 152.38 (138.09, 182.54) vs. 228.25 (215.49, 248.95), Shannon index: 2.37 (1.68, 2.89) vs. 3.39 (3.03, 3.63), all P < 0.01], and the Simpson index was significantly increased [0.21 (0.11, 0.33) vs. 0.07 (0.06, 0.12), P < 0.01], which indicated the gut microbiota diversity of the severe pneumonia group was decreased. (3) Analysis of β diversity of gut microbiota, principal coordinate analysis (PCoA) showed that gut microbiota structural with the healthy control group was similar, while that in the severe pneumonia group was different. Adonis analysis showed that the structural of the gut microflora revealing significant differences between the severe pneumonia group and the healthy control group (R 2 = 0.061, P = 0.05). (4) Analysis of phylum difference gut microflora showed that, compared with the healthy control group, the proportion of Firmicutes in severe pneumonia group was decreased [27.36 (18.12, 39.28)% vs. 52.25 (38.36, 63.82)%, P = 0.02], the proportions of Actinobacterias, Synergistetes and Fusobacterias were increased [2.30 (0.30, 4.80)% vs. 0.02 (0.00, 0.06)%, 0.36 (< 0.01, 0.57)% vs. < 0.01 (< 0.01, < 0.01)%, 0.01 (< 0.01, 0.08)% vs. < 0.01 (< 0.01, < 0.01)%, all P < 0.05]. (5) Analysis of genus difference gut microflora showed that, the proportions of Bifidobacterium, Ruminococcus, Pseudobutyrivibrio, Coprococcus, Lachnospira and Prevotella in the severe pneumonia group were significantly lower than those in healthy control group [0.18 (0.01, 0.25)% vs. 3.40 (0.46, 5.78)%, 0.01 (< 0.01, 0.29)% vs. 2.26 (0.84, 4.86)%, 0.01 (< 0.01, 0.02)% vs. 2.73 (1.87, 5.74)%, 0.02 (< 0.01, 0.07)% vs. 0.80 (0.50, 2.32)%, < 0.01 (< 0.01, < 0.01)% vs. 0.88 (0.33, 2.08)%, 0.02 (< 0.01, 0.31)% vs. 7.74 (0.07, 36.27)%, all P < 0.05]; the proportions of Escherichia and Enterococcus in the severe pneumonia group were higher than those in healthy control group, but there was no difference between the two groups [2.00 (0.57, 10.23)% vs. 1.16 (0.23, 2.68)%, 0.02 (< 0.01, 0.42)% vs. < 0.01 (< 0.01, 0.04)%, both P > 0.05]; the proportions of Fusobacterium and Staphylococcus in severe pneumonia group were significantly higher than those in healthy control group [0.01 (< 0.01, 0.08)% vs. < 0.01 (< 0.01, < 0.01)%, 0.01 (< 0.01, 0.02)% vs. < 0.01 (< 0.01, < 0.01)%, both P < 0.05]., Conclusions: Gut microbiota dysbiosis in patients with severe pneumonia shows that the abundance and diversity decrease, structure of intestinal flora changes, and beneficial symbiotic bacteria decrease and pathogenic bacteria increase, which may be associated with the occurrence and development of severe pneumonia.

We have synthesized a series of new β-iminoenolates and their corresponding difluoroboron complexes without any traditional gelation moieties, and some of them were able to gelatinize organic solvents. It was found that the presence of halogen atoms as substituents had a significant effect on gelation ability. In particular, bromo-containing compounds 4 A and 4 B exhibited excellent gelation abilities compared with other halogen-substituted gelators. By analyses of the single-crystal structure, the PXRD pattern of the xerogel, and electronic spectral changes during gelation, we deemed that π-π, C-H⋅⋅⋅F, and C-H⋅⋅⋅Br interactions were the driving forces for the gelation of 4 B. Interestingly, (Z)-1-(4-bromophenyl)-2-(3-methylpyrazin-2-yl)ethen-1-ol (8 A), prepared in this work, is the lowest-molecular-weight organogelator to have been reported. It should be noted that although β-iminoenolates 3 A-5 A are nonemissive in solution, they emit strong yellow light in organogels, which suggests aggregation-induced emissive activity, whereas the difluoroboron complexes 3 B-5 B show strong fluorescence in solutions, organogels, and xerogel-based films. Moreover, we found that the emission of 4 B in a nanofiber-based film could be quenched significantly upon exposure to gaseous trifluoroacetic acid and that the decay time and detection limit were 0.5 s and 0.17 ppm, respectively. Thus, through this work we have provided a new strategy for the design of nontraditional π gelators by introducing halogen atoms into π-conjugated systems with moderate polarities., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

New indolocarbazole derivatives emitting strong blue light have been synthesized. It is found that the strong π–π interactions between indolocarbazoles 4–6 without long carbon chains lead to the formation of crystal or crystal-like aggregates. We have previously found that tert-butyl could tune the strength of π–π interactions between carbazole units and the organogels were obtained from tert-butyl substituted carbazoles directed by balanced π–π interactions. Herein, hexadecyl groups were introduced into N-positions of indolocarbazoles in order to reduce the strength of π–π interactions between indolocarbazoles, and compounds 7–9 were prepared. It is interesting that compounds 8 and 9 could form stable organogels in alcohols, acetone, DMSO, and so on, upon ultrasound stimulation. Combined with the results of electronic spectra, XRD patterns and the optimized molecular length based on the semiempirical (AM1) calculations, we suggested the molecular packing modes in gel states, in which the lamellar structures were involved. Although the fluorescence emission of indolocarbazoles 8 and 9 decreased during the gel formation to some extent, the obtained gel nanofibers still emitted strong blue light and the fluorescence emission of the film based on xerogel 9 decreased significantly upon exposure to gaseous TNT. It meant that the xerogels based on indolocarbazoles could be used as fluorescent sensors for detecting vapors of explosives.