The radiation of electromagnetic and mechanical waves depends not only on the intrinsic properties of the emitter but also on the surrounding environment. This principle has laid the foundation for ...the development of lasers, quantum optics, sonar, musical instruments and other fields related to wave–matter interaction. In the conventional wisdom, the environment is defined exclusively by its eigenstates, and an emitter radiates into and interacts with these eigenstates. Here we show experimentally that this scenario breaks down at a non-Hermitian degeneracy known as an exceptional point. We find a chirality-reversal phenomenon in a ring cavity where the radiation field reveals the missing dimension of the Hilbert space, known as the Jordan vector. This phenomenon demonstrates that the radiation field of an emitter can become fully decoupled from the eigenstates of its environment. The generality of this striking phenomenon in wave–matter interaction is experimentally confirmed in both electromagnetic and acoustic systems. Our finding transforms the fundamental understanding of light–matter interaction and wave–matter interaction in general, and enriches the intriguing physics of exceptional points.The modes of the radiation field generated from an emitter are usually determined by the eigenstates of the surrounding environment. However, this scenario breaks down in a non-Hermitian system, at the spectral degeneracy known as an exceptional point.
The introduction of metasurfaces has renewed the Snell's law and opened up new degrees of freedom to tailor the optical wavefront at will. Here, we theoretically demonstrate that the generalized ...Snell's law can be achieved for reflected acoustic waves based on ultrathin planar acoustic metasurfaces. The metasurfaces are constructed with eight units of a solid structure to provide discrete phase shifts covering the full 2π span with steps of π/4 by coiling up the space. By careful selection of the phase profiles in the transverse direction of the metasurfaces, some fascinating wavefront engineering phenomena are demonstrated, such as anomalous reflections, conversion of propagating waves into surface waves, planar aberration-free lens and nondiffracting Bessel beam generated by planar acoustic axicon. Our results could open up a new avenue for acoustic wavefront engineering and manipulations.
Two multifunctional, ether-bridged tricarboxylic acids, 2-(4-carboxylphenoxy)terephthalic acid (H3cpta) and 2-(3,5-dicarboxylatobenzyloxy)benzoic acid (H3dbba), were used as unexplored and highly ...versatile building blocks for the hydrothermal generation of a novel series of cadmium(ii) metal-organic architectures. These were formulated as Cd(μ-Hcpta)(phen)(py)n (1), {Cd3(μ5-cpta)2(phen)3·8H2O}n (2), {Cd3(μ5-cpta)2(2,2'-bipy)3·6H2O}n (3), {Cd(μ3-cpta)(Hbpa)·2H2O}n (4), {Cd6(μ4-cpta)2(μ6-cpta)2(H2biim)2(H2O)6·5H2O}n (5), Cd3(μ4-cpta)2(μ-prz)(H2O)4n (6), {Cd3(μ4-dbba)2(phen)3·H2O}n (7), and {Cd3(μ3-dbba)2(2,2'-bipy)3(H2O)3·2H2O}n (8) on the basis of single-crystal X-ray diffraction, elemental analysis, FTIR, PXRD, and TGA data. Products 1-8 were assembled in the presence of N-donor crystallization mediators selected from pyridine (py), 1,10-phenanthroline (phen), 2,2'-bipyridine (2,2'-bipy), bis(4-pyridyl)amine (bpa), 2,2'-biimidazole (H2biim), or piperazine (prz). The nature of the crystallization mediator and/or the type of principal tricarboxylate building block have a significant effect on the structural diversity, dimensionality, and topology of the resulting cadmium-organic architectures. These span from 1D (1, 8) and 2D (7) coordination polymers to 3D metal-organic frameworks (2-6) with intricate topologies (3,4,5T64 in 2 and 3, utp (103)-d in 4, 3,4,4T9 in 6) that also include unprecedented types in 5 and 7. Besides, MOF 6 features a 3D + 3D two-fold interpenetrated framework. Luminescent and photocatalytic properties of selected materials were investigated, showing that coordination polymer 7 is a promising photocatalyst for the UV-light-driven degradation of methylene blue as a model organic dye pollutant. Moreover, products 7 and 8 are the first examples of structurally characterized coordination compounds derived from H3dbba.
An optical nose chip is developed using surface functionalized mesoporous colloidal photonic crystal beads as elements. The prepared optical nose chip displays excellent discrimination among a very ...wide range of compounds, not only the simplex organic vapors from the different or same chemical family, but also the complex expiratory air from different people.
Ovarian cancer (OC) is the highest frequent malignant gynecologic tumor with very complicated pathogenesis. The purpose of the present academic work was to identify significant genes with poor ...outcome and their underlying mechanisms. Gene expression profiles of GSE36668, GSE14407 and GSE18520 were available from GEO database. There are 69 OC tissues and 26 normal tissues in the three profile datasets. Differentially expressed genes (DEGs) between OC tissues and normal ovarian (OV) tissues were picked out by GEO2R tool and Venn diagram software. Next, we made use of the Database for Annotation, Visualization and Integrated Discovery (DAVID) to analyze Kyoto Encyclopedia of Gene and Genome (KEGG) pathway and gene ontology (GO). Then protein-protein interaction (PPI) of these DEGs was visualized by Cytoscape with Search Tool for the Retrieval of Interacting Genes (STRING). There were total of 216 consistently expressed genes in the three datasets, including 110 up-regulated genes enriched in cell division, sister chromatid cohesion, mitotic nuclear division, regulation of cell cycle, protein localization to kinetochore, cell proliferation and Cell cycle, progesterone-mediated oocyte maturation and p53 signaling pathway, while 106 down-regulated genes enriched in palate development, blood coagulation, positive regulation of transcription from RNA polymerase II promoter, axonogenesis, receptor internalization, negative regulation of transcription from RNA polymerase II promoter and no significant signaling pathways. Of PPI network analyzed by Molecular Complex Detection (MCODE) plug-in, all 33 up-regulated genes were selected. Furthermore, for the analysis of overall survival among those genes, Kaplan-Meier analysis was implemented and 20 of 33 genes had a significantly worse prognosis. For validation in Gene Expression Profiling Interactive Analysis (GEPIA), 15 of 20 genes were discovered highly expressed in OC tissues compared to normal OV tissues. Furthermore, four genes (BUB1B, BUB1, TTK and CCNB1) were found to significantly enrich in the cell cycle pathway via re-analysis of DAVID. In conclusion, we have identified four significant up-regulated DEGs with poor prognosis in OC on the basis of integrated bioinformatical methods, which could be potential therapeutic targets for OC patients.
The undrained shear strength of surficial marine clays is a significant parameter for engineering construction and geological disaster assessment. The full-flow penetration test is an effective ...method to evaluate marine clay strength. Currently, this method is mainly used for deep penetration, in which the stable full-flow failure state with plasticity solutions is reached; however, surficial penetration lacks a theoretical basis, and related empirical methods are still being explored, especially considering the effect of ambient water. Based on this, first, a model in the framework of computational fluid dynamics is proposed to simulate the whole penetration process of a ball penetrometer in two-phase materials (i.e., marine clay and ambient water). Furthermore, centrifugal penetration tests of two typical clay samples (i.e., South China Sea soil and kaolin clay) are used to verify the accuracy of the proposed relative motion model. Second, the characteristics of the penetration resistance factor during the whole penetration in homogenized marine clays are obtained, and the relevant mechanism is analyzed by the variation in the velocity field, volume fraction and streamline of two-phase materials. Finally, the critical depth to distinguish between surficial and stable penetration is given as 6.5 times the ball diameter; the penetration resistance factor is divided into surficial and stable penetration resistance factors, and dimensionless evaluation methods are established, which provides the basis for obtaining the strength of surficial marine clays.
Cytoplasmic lncRNAs have been found to directly interact with target mRNAs and regulate their stability. In this study, we aimed to study the molecular mechanism underlying the function of m6A as a ...central regulator in chemoresistance and CML proliferation. In this study, we established three mice groups (control group, ADR‐R group and ADR‐R + shLINC00470 group). We detected PTEN mRNA expression in the presence of LINC00470 in the mice models, as well as in the KCL22 and K562 cells. LINC00470 was significantly enriched for PTEN mRNA to exhibit a negative regulatory relationship between LINC00470 and PTEN mRNA. However, the alteration of LINC00470 had no effect on the luciferase activity of PTEN promoter, while the half‐life of PTEN mRNA was affected. It was further validated that LINC00470 down‐regulated PTEN expression by positively regulating the m6A modification of PTEN mRNA via RNA methyltransferase METTL3. Moreover, the relative expression of LC3II, Beclin‐1, ATG7 and ATG5 was all decreased in cells treated with LINC00470, and down‐regulated PTEN expression was observed in chemo‐resistant cells, while the expression of PTEN was rescued by the transfection of shMETTL3 into chemo‐resistant cells. Moreover, the knockdown of METTL3 also restored the normal level of PTEN m6A modification and LINC00470 expression in chemo‐resistant cells. In conclusion, our results demonstrated the molecular mechanism underlying the effect of LINC00470 on CML by reducing the PTEN stability via RNA methyltransferase METTL3, thus leading to the inhibition of cell autophagy while promoting chemoresistance in CML.
5-(3,4-Dicarboxylphenyl)picolinic acid (H
3
dppa) was applied as a novel tricarboxylic acid block with phthalate and picolinate functionalities for the aqueous-medium assembly of seven new ...coordination compounds, namely, Mn
2
(μ-Hdppa)
2
(phen)
2
(H
2
O)
2
(
1
), {Mn(μ-Hdppa)(2,2′-H
2
biim)(H
2
O)·H
2
O}
n
(
2
), Ni(Hdppa)(phen)
2
·4H
2
O (
3
), {Ni(μ-Hdppa)(μ-4,4′-bipy)(H
2
O)·H
2
O}
n
(
4
), {Cu
3
(μ
3
-dppa)(μ-Hdppa)(phen)
4
2
Cu(μ-Hdppa)
2
·10H
2
O}
n
(
5
), {Ni
3
(μ-dppa)
2
(μ-1,4-bpb)
2
(H
2
O)
6
·4H
2
O}
n
(
6
), and {Zn
3
(μ
4
-dppa)
2
(phen)
2
(H
2
O)
2
·4H
2
O}
n
(
7
). These products
1–7
represent the first structurally characterized examples of the coordination compounds derived from H
3
dppa. Compounds
1–7
were assembled in the presence of various N-donor supporting ligands acting as crystallization mediators, which were selected from 1,10-phenanthroline (phen), 2,2′-biimidazole (H
2
biim), 4,4′-bipyridine (4,4′-bipy), or 1,4-bis(pyrid-4-yl)benzene (1,4-bpb). Full characterization of
1–7
by IR spectroscopy, thermogravimetric (TGA), elemental, and topological analyses, as well as powder (PXRD) and single-crystal X-ray diffraction, was performed. The structural types range from the discrete 0D complexes (
1
and
3
) and 1D coordination polymers with a
2C1
topology (
2
,
5
, and
6
) to the 2D metal–organic layers with an
sql
topology (
4
and
7
). The structural diversity of
1–7
is driven by various factors, including the metal(
ii
) node nature, deprotonation degree of H
3
dppa, or type of crystallization mediator. The magnetic properties of
1
,
2
,
4
, and
6
were studied and modeled, revealing antiferromagnetic (in
1
,
2
, and
6
) or ferromagnetic (in
4
) interactions between adjacent metal(
ii
) centers. The luminescence of
7
was also investigated. Moreover, the photocatalytic activity of
1–7
was studied for the degradation of methylene blue as a model dye pollutant, disclosing that the nickel(
ii
) coordination polymer
4
is the most active catalyst. The observed catalytic activity of
1–7
correlates well with their band gap energies determined by the UV-diffuse reflectance method.
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•Performance analysis of controllable-blade vertical axis turbine is conducted.•Numerical and experimental studies of the proposed turbine are made.•A cam plate is used to control the ...six blades of the vertical axis turbine.•The performance of CBVAT is 143% and 103% higher than that of the FBVAT and ST.
Phasing out high-carbon-emission fossil fuels and using renewable energy have become a global consensus for mitigating climate change. For the application of renewable energy, this study proposes a high-efficiency controllable-blade vertical axis turbine, which has six blades and a cam plate, for ocean current power generation. A novel design for the turbine using cam to control the opening and closing of blades to enhance the performance of vertical axis turbines. The design feature of the drag-type blade is to be active or open quickly in downstream. The effective area of the blade under thrust is increased to enhance the performance. On the other hand, the blade is designed to be inactive or close quickly in upstream and the drag of blade in upstream can be reduced. A commercial software, ANSYS FLUENT is used to simulate the performance of the vertical turbine. The streamline, velocity, and pressure around the turbines are then obtained. The power coefficients and torques are evaluated at various angular velocities and tip speed ratios and are validated by experimental results. The maximum power coefficient of the proposed turbine occurs at an angular velocity ratio of 4 with quick opening of blades and is higher than that of 3, 5, or 6 by 3.4 %, 2.7 %, or 7.4 %, respectively. In addition, performance comparisons among controllable-blade vertical axis turbine, fixed-blade vertical axis turbine, and Savonius turbine are made. The results show that the maximum power coefficient of the presented controllable-blade vertical axis turbine is 143 % and 103 % higher than that of the fixed-blade vertical axis turbine and Savonius turbine at V = 1 m/s, respectively.
Antiphospholipid antibody syndrome (APS) is a systemic, autoimmune, prothrombotic disease characterized by persistent antiphospholipid antibodies, thrombosis, recurrent abortion, complications during ...pregnancy, and occasionally thrombocytopenia. At present, there is no consensus on the treatment of this disease. Long-term anticoagulation is recommended in most cases in patients with thrombotic APS. This study aimed to evaluate whether aspirin combined with low-molecular-weight heparin (LMWH) can improve the live birth rate in antiphospholipid syndrome and its correlation with D-dimer.
The data were retrieved from the WanFang Data, CBM, VIP, CNKI, the Cochrane Library, PubMed, EMBASE, OVID, and Web of Science databases. We collected data on randomized controlled trials of aspirin combined with LMWH in the treatment of pregnant women with APS. The "Risk of Bias Assessment" tool and the "Jadad Scale" provided by the Cochrane Collaboration were used to evaluate the risk of bias and quality of the collected literature. The risk ratio (RR) and its 95% confidence interval (CI) were determined using Statase-64 software.
In this study, a total of 11 studies were included, comprising a total of 2101 patients. The live birth rate in pregnant women with APS was higher on administration of aspirin combined with LMWH than with aspirin alone (RR = 1.29, 95% CI = 1.22-1.35, P < .001). d-dimer concentration in plasma predicted the live birth rate, which was higher below the baseline than above it (RR = 1.16, 95% CI = 1.09-1.23, P < .001). The subgroup analysis of the live birth rate was carried out based on the course of treatment, and the results were consistent with the overall results. Begg funnel plot test revealed no publication bias. Sensitivity analysis showed that deleting any study did not affect the results.
Aspirin combined with LMWH for APS may improve live birth rate, and detection of d-dimer levels in APS pregnant women may predict pregnancy complications and guide the use of anticoagulants.
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