A microporous three-dimensional (3D) hydrogen-bonded organic framework (HOF-20) has been constructed from an aromatic-rich tetratopic carboxylic acid, ...5-(2,6-bis(4-carboxyphenyl)pyridin-4-yl)isophthalic acid (H
BCPIA). The activated HOF-20a has a moderately high Brunauer-Emmett-Teller (BET) surface area of 1323 m
g
and excellent stability in water and HCl aqueous solution. HOF-20 exhibits highly efficient turn-up fluorescent sensing of aniline in water with a detection limit of 2.24 μM and is selective toward aniline in the presence of aromatic interferents, owing to the hydrogen bonding and edge-to-face π-π stacking interactions between the HOF-20 host and the guest aniline molecules, as demonstrated in the single-crystal X-ray structure of HOF-20⊃aniline. Density functional theory (DFT) calculations further demonstrate that the recognition of aniline molecules by HOF-20 could restrict the rotation of the aromatic rings in H
BCPIA linkers, reducing the nonradiative decay pathways upon photoexcitation and subsequently enhancing the fluorescence intensity.
When operating within the environments rich with sodium chloride, steel bars of reinforced concrete structures are often subject to corrosion caused by surrounding erosive materials, and the ...associated rust expansion force due to corrosion takes a critical role in determining the durability of relevant reinforced concrete structures. By investigating the corrosion course of steel reinforcement with theory of elasticity, a numerical rust expansion model is established for the moment of concrete surface rupture based on non-uniform sin function. Cuboid reinforced concrete specimen with squared cross sections is tested to analyze the rust expansion when concrete cracks due to corrosive forces. The utility of the established expansion model is validated by numerical simulation with Abaqus through the comparison between the associated outcomes. The impacts of steel bar diameter and concrete cover thickness on the magnitude of rust expansion force are discussed.
Neoadjuvant chemotherapy with dual-targeted therapy is the standard treatment for human epidermal growth factor 2 (HER2)-positive breast cancer. Although the dual-targeted therapy has significantly ...improved the pathological complete response (pCR) rate, further investigation is needed to identify biomarkers that predict the response to neoadjuvant therapy.
This retrospective study analyzed 353 patients with HER2-positive breast invasive ductal carcinoma. The correlation between clinicopathological factors and pCR rate was evaluated. A nomogram was constructed based on the results of the multivariate logistic regression analysis to predict the probability of pCR.
The breast pCR (b-pCR) rate was 56.1% (198/353) and the total pCR (t-pCR) rate was 52.7% (186/353). Multivariate analysis identified ER status, PR status, HER2 status, Ki-67 index, and neoadjuvant chemotherapy regimens as independent indicators for both b-pCR and t-pCR. The nomogram had an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI: 0.68-0.78). According to the nomogram, the t- pCR rate was highest in the ER-PR- HER2-positive patients (131/208) and lowest in the ER + PR + HER2-positive patients (19/73). The subgroup analyses showed that there was no significant difference in pCR rate among the neoadjuvant chemotherapy regimens in ER positive, PR positive, HER2 IHC 2 + , Ki67 index < 30% population. However, for ER-PR-HER2-positive patients, the neoadjuvant chemotherapy regimen has a great influence on the pCR rates.
Patients with ER-negative, PR-negative, HER2 3 + and high KI-67 index were more likely to achieve pCR. THP may be used as an alternative to AC-THP or TCbHP in selected HER2-positive patients.
Coffee-ring effect is an omnipresent phenomenon, it features the circular deposition on the surface after the evaporation of a droplet containing particles. Ever since the seminal report of ...coffee-ring effect in 1997 from Deegan (Nature 1997, 389 (6653), 827–829), coffee-ring effect related studies have been thriving in various fields. Coffee-ring effect is a spontaneous phenomenon, the capillary flow from the center to the edge of droplet pushes all solute towards the droplet's edge. Therefore, any process involving small droplets especially in the analytical chemistry has to deal with coffee-ring effect.
This review aims to offer an in-depth understanding of coffee-ring effect in analytical chemistry, includes the formation mechanism, controlling factors, as well as categorized applications based on the essence of factors. Lastly, the limitation and the future trends of this technique in analytical chemistry are discussed, offering our insights on the development of this technique and aiming to promote the application of this technique.
•An in-depth decipher of coffee-ring effect mechanism.•Categorized applications based on the essence of coffee-ring effect.•Regular coffee-ring effect as an unique sample enrichment approach.•Various approaches for the coffee-ring effect suppression.
Malayan pangolin SARS-CoV-2-related coronavirus (SARSr-CoV-2) is closely related to SARS-CoV-2. However, little is known about its pathogenicity in pangolins. Using CT scans we show that SARSr-CoV-2 ...positive Malayan pangolins are characterized by bilateral ground-glass opacities in lungs in a similar manner to COVID-19 patients. Histological examination and blood gas tests are indicative of dyspnea. SARSr-CoV-2 infected multiple organs in pangolins, with the lungs the major target, and histological expression data revealed that ACE2 and TMPRSS2 were co-expressed with viral RNA. Transcriptome analysis indicated that virus-positive pangolins were likely to have inadequate interferon responses, with relative greater cytokine and chemokine activity in the lung and spleen. Notably, both viral RNA and viral proteins were detected in three pangolin fetuses, providing initial evidence for vertical virus transmission. In sum, our study outlines the biological framework of SARSr-CoV-2 in pangolins, revealing striking similarities to COVID-19 in humans.
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•Seven Zr-based metal-organic frameworks were screened for OAAs capture from water.•The qm values over MOF-808F reached to 621.1 mg g−1 for ASA and 709.2 mg g−1 for ROX.•MOF-808F ...showed excellent selectivity and reusability, which were superior to MOF-808.•Electrostatic, H-bonding and π-π interactions were observed in ASA@MOF-808F.•While coordination interaction was the dominant force between ASA and MOF-808.
It is imperative to remove organicarsenic acids (OAAs) from water because they can convert into highly toxic inorganic arsenic compounds in natural environment via biotic and abiotic degradation routes. Herein, seven Zr-based metal-organic frameworks (Zr-MOFs) including DUT-67, UiO-66, UiO-67, MOF-808, MOF-808F, NU-1000, NU-1000B with various structures were screened for the adsorptive removal of representative OAAs including p-arsanilic acid (ASA) and roxarsone (ROX) in water media. Initial screening found that MOF-808 and MOF-808F have the largest adsorption capacities. Therefore, their adsorption behaviors including adsorption kinetics, isotherms, specificity and effects of pH were fully investigated. Remarkably, MOF-808F had the second largest maximum adsorption capacities of ASA (621.1 mg g−1) and ROX (709.2 mg g−1) among the reported MOF-based adsorbents. In addition, MOF-808F showed excellent selectivity and reusability and no observable drop of adsorption efficiency was found in the presence of equimolar competing ions (Cl−, OAc− or SO42−) or after three successive adsorptive runs. By contrast, MOF-808 had inferior adsorption specificity and reusability in spite of the very similar structure with MOF-808F. The structure-dependent adsorption performances can be explained by the distinct adsorptive mechanisms, which were revealed by zeta potential measurements, X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculation etc. The dominant interaction between MOF-808 and ASA was coordination interactions, while ASA adsorption over MOF-808F was governed by the synergistic effect of π-π stacking, hydrogen bonding, and electrostatic interactions. This work no only presented an excellent adsorbent (MOF-808F) toward OAAs, but also revealed the structure dependent adsorption performances/mechanisms.
Background
Breast cancer (BC) remains the leading cause of cancer‐related deaths worldwide. High recurrence risk Luminal BC receives adjuvant chemotherapy in addition to standard hormone therapy. ...Considering the heterogeneity of Luminal B BC, a more accurate classification model is urgently needed.
Methods
In this study, we retrospectively reviewed the data of 1603 patients who were diagnosed with HER2‐negative breast invasive ductal carcinoma. According to the expression level of PR and Ki‐67 index, the Luminal B (HER2‐negative) BCs were divided into three groups: ER+PR−Ki67low (ER‐positive, PR‐negative, and Ki‐67 index <20%), ER+PR+Ki67high (ER‐positive, PR‐positive, and Ki‐67 index ≥20%), and ER+PR−Ki67high (ER‐positive, PR‐negative, and Ki‐67 index ≥20%). The cox proportional hazards regression model was used to evaluate the correlation between each variable and outcomes. Besides, discriminatory accuracy of the models was compared using the area under the receiver operating characteristic curve and log‐rank χ2 value.
Results
The analysis results showed that there was a significant correlation between subtypes using this newly defined classification and overall survival (p < 0.001) and disease‐free survival (DFS) (p < 0.001). Interestingly, patients in the ER+PR−Ki67high subgroup have the worst survival outcome in Luminal B (HER2‐negative) subtype, similar to Triple‐negative patients. Besides, the ER+PR+Ki67high has worse 5‐year DFS compared with Luminal A group. There was a significant relationship between the regrouping subtype and the recurrence score index (RI) (p < 0.001). Moreover, the results showed that patients in ER+PR–Ki67high subtype were more likely to have high RI for distance recurrence (RI‐DR) and local recurrence (RI‐LRR). Our newly defined classification has a better discrimination ability to predict survival outcome and recurrence score of Luminal B (HER2‐negative) BC patients, which may help in clinical decision‐making for individual treatment.
Our newly defined classification has a better discrimination ability to predict survival outcome and recurrence score of Luminal B (HER2 negative) breast cancer, which may help in clinical decision‐making for individual treatment.
As a noninvasive perfusion-weighted MRI technique, arterial spin-labeling (ASL) was becoming increasingly used to evaluate cerebral hemodynamics in many studies. The relation between ASL-MRI and ...crossed cerebellar diaschisis (CCD) was rarely discussed. In this study, the aim of our study was to assess the performance of ASL-MRI in the detection of crossed cerebellar diaschisis after stroke in compared with single-photon emission CT (SPECT).
17 of 51(33.3%) patients revealed CCD phenomenon by the SPECT method. In CCD-positive group, CBF
of ipsilateral cerebellar were significantly increased compared with contralateral cerebellar (p < 0.0001) while no significant differences (p = 0.063, > 0.001) in the CCD-negative group. Positive correlation was detected between admission National institute of health stroke scale (NIHSS) and asymmetry index of SPECT (AI
) (r = 0.351, p = 0.011), AI
(r = 0.372, p = 0.007); infract volume and AI
(r = 0.443, p = 0.001), AI
(r = 0.426, p = 0.002). Significant correlation was also found between cerebral blood flow of SPECT (CBF
) and CBF
, AI
and AI
(r = 0.204, p = 0.04; r = 0.467, p = 0.001, respectively). Furthermore, the area under the receiver operating characteristic (ROC) curve value of AI
was 0.829.
CBF derived from ASL-MRI could be valuable for assessment of CCD in supratentorial stroke patients. Additionally, CCD was significantly associated with larger ischemic volume and higher initial NIHSS score.
The identification of SARS-CoV-2-like viruses in Malayan pangolins (
) has focused attention on these endangered animals and the viruses they carry. We successfully isolated a novel respirovirus from ...the lungs of a dead Malayan pangolin. Similar to murine respirovirus, the full-length genome of this novel virus was 15 384 nucleotides comprising six genes in the order 3'-(leader)-NP-P-M-F-HN-l-(trailer)-5'. Phylogenetic analysis revealed that this virus belongs to the genus
and is most closely related to murine respirovirus. Notably, animal infection experiments indicated that the pangolin virus is highly pathogenic and transmissible in mice, with inoculated mice having variable clinical symptoms and a fatality rate of 70.37 %. The virus was found to replicate in most tissues with the exception of muscle and heart. Contact transmission of the virus was 100 % efficient, although the mice in the contact group displayed milder symptoms, with the virus mainly being detected in the trachea and lungs. The isolation of a novel respirovirus from the Malayan pangolin provides new insight into the evolution and distribution of this important group of viruses and again demonstrates the potential infectious disease threats faced by endangered pangolins.
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•Hydrophobic perfluoroalkane-decorated MOFs immobilize ultrafine Pd NPs.•High activity and regioselectivity in the direct C–H arylation of indoles were obtained in water.•The highly ...dispersed Pd NPs catalysts can be recovered and reused.
The use of water as reaction medium in the heterogeneous activation of C–H bonds has numerous advantages in terms of environmental benign, safety and cost efficiency impact. However, it is severely hampered because the reactants are difficult to dissolve in water and contact with the active sites of heterogeneous catalysts. Herein, we choose perfluoroalkane-functionalized mesoporous metal-organic framework (MOF) NU-1000 as a hydrophobic platform to encapsulate ultrafine palladium nanoparticles (Pd NPs) for C–H activation in water. The resultant Pd NPs stabilized by the perfluoroalkane exhibited high activity and regioselectivity in the direct C–H arylation of indoles in water. The introduction of perfluoroalkane chains into the mesoporous pores of NU-1000 provides hydrophobic surfaces to facilitate access of the reactants to the active sites to guarantee the high activity.
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