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Minghua Formation in Gangdong Oilfield belongs to high permeability reservoir. The dispersion degree of residual oil is a very important production target. The dominant reserves in reservoirs are extracted by the abundance parameters of residual dominant reserves. The residual oil dispersion degree is characterized by the index of unit area, distribution density and shape index, and the weight of each index is determined by the entropy weight method. Finally, the residual oil fraction is formed. The results show that for a stable reservoir, the residual oil dispersion in different development stages include the following stages: rising, rapid rising, fluctuating downward and secondary rising. The characterization index is used to evaluate the Nm3-4-1 formation of Gangdong oilfield. The residual oil dispersion of the formation increases steadily with the development. At present, the residual oil dispersion begins to decrease. The new characterization method of residual oil dispersion effectively reflects the stage effect of reservoirs and provides a basis for improving oil recovery.

ObjectiveDietary fibre has beneficial effects on energy metabolism, and the majority of studies have focused on short-chain fatty acids produced by gut microbiota. Ginseng has been reported to aid in body weight management, however, its mechanism of action is not yet clear. In this study, we focused on the potential modulating effect of ginseng on gut microbiota, aiming to identify specific strains and their metabolites, especially long-chain fatty acids (LCFA), which mediate the anti-obesity effects of ginseng.DesignDb/db mice were gavaged with ginseng extract (GE) and the effects of GE on gut microbiota were evaluated using 16S rDNA-based high throughput sequencing. To confirm the candidate fatty acids, untargeted metabolomics analyses of the serum and medium samples were performed.ResultsWe demonstrated that GE can induce Enterococcus faecalis, which can produce an unsaturated LCFA, myristoleic acid (MA). Our results indicate that E. faecalis and its metabolite MA can reduce adiposity by brown adipose tissue (BAT) activation and beige fat formation. In addition, the gene of E. faecalis encoding Acyl-CoA thioesterases (ACOTs) exhibited the biosynthetic potential to synthesise MA, as knockdown (KD) of the ACOT gene by CRISPR-dCas9 significantly reduced MA production. Furthermore, exogenous treatment with KD E. faecalis could not reproduce the beneficial effects of wild type E. faecalis, which work by augmenting the circulating MA levels.ConclusionsOur results demonstrated that the gut microbiota-LCFA-BAT axis plays an important role in host metabolism, which may provide a strategic advantage for the next generation of anti-obesity drug development.

Bubbles locating in microfluidic chamber can produce acoustic streaming vortices by applying travelling surface acoustic wave oscillation in an ultrasonic range, which can be used to drive bio-samples to move within the flow field. In this paper, a strategy of bubble array configured in a large number of regularly arranged horseshoe structures is proposed to capture and rotate cells simultaneously. By modifying the geometric parameters of the horseshoe structure and microfluidic setting, high bubble homogeneity and cell trapping percentage was achieved. The simulation and experimental results of the bubble-induced streaming vortices were confirmed to be consistent. Through experiments, we achieved both in-plane and out-of-plane rotation of arrayed HeLa cells trapped by the bubbles. Out-of-plane rotation was used to reconstruct the 3D (three-dimensional) cell morphology, which was demonstrated to be useful in calculating cell geometry related parameters. We believe that this bubble array based cell rotation method is expected to be a promising tool for the investigation of bioengineering, biophysics, medicine, and cell biology.

Combining high-throughput screening and machine learning models is a rapidly developed direction for the exploration of novel optoelectronic functional materials. Here, we employ random forests regression (RFR) model to investigate the second harmonic generation (SHG) coefficients of nonlinear optical crystals with distinct diamond-like (DL) structures. 61 DL structures in Inorganic Crystallographic Structure Database (ICSD) are selected, and four distinctive descriptors, including band gap, electronegativity, group volume and bond flexibility, are used to model and predict second-order nonlinearity. It is demonstrated that the RFR model has reached the first-principles calculation accuracy, and gives validated predictions for a variety of representative DL crystals. Additionally, this model shows promising applications to explore new crystal materials of quaternary DL system with superior mid-IR NLO performances. Two new potential NLO crystals, Li 2 CuPS 4 with ultrawide bandgap and Cu 2 CdSnTe 4 with giant SHG response, are identified by this model.

Traumatic brain injury (TBI) triggers a series of neuroinflammatory processes that contribute to evolution of neuronal injury. The present study investigated the neuroprotective effects and anti-inflammatory actions of berberine, an isoquinoline alkaloid, in both in vitro and in vivo TBI models. Mice subjected to controlled cortical impact injury were injected with berberine (10 mg·kg(-1)) or vehicle 10 min after injury. In addition to behavioral studies and histology analysis, blood-brain barrier (BBB) permeability and brain water content were determined. Expression of PI3K/Akt and Erk signaling and inflammatory mediators were also analyzed. The protective effect of berberine was also investigated in cultured neurons either subjected to stretch injury or exposed to conditioned media with activated microglia. Berberine significantly attenuated functional deficits and brain damage associated with TBI up to day 28 post-injury. Berberine also reduced neuronal death, apoptosis, BBB permeability, and brain edema at day 1 post-injury. These changes coincided with a marked reduction in leukocyte infiltration, microglial activation, matrix metalloproteinase-9 activity, and expression of inflammatory mediators. Berberine had no effect on Akt or Erk 1/2 phosphorylation. In mixed glial cultures, berberine reduced TLR4/MyD88/NF-κB signaling. Berberine also attenuated neuronal death induced by microglial conditioned media; however, it did not directly protect cultured neurons subjected to stretch injury. Moreover, administration of berberine at 3 h post-injury also reduced TBI-induced neuronal damage, apoptosis and inflammation in vivo. Berberine reduces TBI-induced brain damage by limiting the production of inflammatory mediators by glial cells, rather than by a direct neuroprotective effect.

Increasing evidence confirmed that the Warburg effect plays an important role involved in the progression of malignant tumors. Resibufogenin (RES) has been proved to have a therapeutic effect in multiple malignant tumors. However, the mechanism of whether RES exerted an antitumor effect on breast cancer through regulating the Warburg effect is largely unknown. The effect of RES on glycolysis was determined by glucose consumption, lactate production, ATP generation, extracellular acidification rate and oxygen consumption rate in breast cancer cells. The total RNA and protein levels were respectively measured by RT-qPCR and western blot. Cell proliferation and apoptosis were examined using the CCK-8 assay, colony formation assay, and flow cytometry, respectively. The interaction between miR-143-3p and HK2 was verified by dual-luciferase reporter gene assay. We also evaluated the influence of RES on the tumor growth and Warburg effect in vivo. RES treatment significantly decreased glycolysis, cell proliferation and induced apoptosis of both MDA-MB-453 and MCF-7 cells. Simultaneously, the expression of HK2 was decreased in breast cancer cells treated with RES, which was positively associated with tumor size and glycolysis. Moreover, HK2 was a direct target gene of miR-143-3p. Mechanistically, upregulation of miR-143-3p by RES treatment inhibited tumor growth by downregulating HK2-mediated Warburg effect in breast cancer. Our findings suggested that RES exerted anti-tumorigenesis and anti-glycolysis activities in breast cancer through upregulating the inhibitory effect of miR-143-3p on HK2 expression, which provided a new potential strategy for breast cancer clinical treatment.

Cells have different intrinsic markers such as mechanical and electrical properties, which may be used as specific characteristics. Here, we present a microfluidic chip configured with two opposing optical fibers and four 3D electrodes for multiphysical parameter measurement. The chip leverages optical fibers to capture and stretch a single cell and uses 3D electrodes to achieve rotation of the single cell. According to the stretching deformation and rotation spectrum, the mechanical and dielectric properties can be extracted. We provided proof of concept by testing five types of cells (HeLa, A549, HepaRG, MCF7 and MCF10A) and determined five biophysical parameters, namely, shear modulus, steady-state viscosity, and relaxation time from the stretching deformation and area-specific membrane capacitance and cytoplasm conductivity from the rotation spectra. We showed the potential of the chip in cancer research by observing subtle changes in the cellular properties of transforming growth factor beta 1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) A549 cells. The new chip provides a microfluidic platform capable of multiparameter characterization of single cells, which can play an important role in the field of single-cell research.Microfluidics: multiparameter cell characterizationA microfluidic chip utilizing optical fibers and electrodes can determine the mechanical and electrical parameters of different cell types. The biophysical behavior of cells are key markers for cellular identification, as well as for the study of diseased cells. Here, a team led by Wenhui Wang from Tsinghua University report a microfluidic chip that enables simultaneous probing of the mechanical and electrical behavior of single cells. Their device features two optical fibers to induce optical trapping and stretching of the cell, and four electrodes to measure electrical properties and for electrical rotation. They demonstrate the device for five different cell types, and study changes in the properties of cancerous cells.

Manipulation of the light phase lies at the heart of the investigation of light-matter interactions, especially for efficient nonlinear optical processes. Here, we originally propose the angular engineering strategy of the additional periodic phase (APP) for realization of tunable phase matching and experimentally demonstrate the widely tunable phase-matched second harmonic generation (SHG) which is expected for dozens of years. With an APP quartz crystal, the phase difference between the fundamental and frequency-doubled light is continuously angularly compensated under this strategy, which results the unprecedented and efficient frequency doubling at wavelengths almost covering the deep-UV spectral range from 221 to 332 nm. What’s more, all the possible phase-matching types are originally realized simultaneously under the angular engineering phase-matching conditions. This work should not only provide a novel and practical nonlinear photonic device for tunable deep-UV radiation but also be helpful for further study of the light-matter interaction process.A widely tunable phase-matched second harmonic generation (221–332 nm) covering almost the entire deep-UV spectral range is experimentally realized by angular engineering strategy of an additional periodic phase.

Nonlinear frequency conversion is a ubiquitous technique that is used to obtain broad-range lasers and supercontinuum coherent sources. The phase-matching condition (momentum conservation relation) is the key criterion but a challenging bottleneck in highly efficient conversion. Birefringent phase matching (BPM) and quasi-phase matching (QPM) are two feasible routes but are strongly limited in natural anisotropic crystals or ferroelectric crystals. Therefore, it is in urgent demand for a general technique that can compensate for the phase mismatching in universal nonlinear materials and in broad wavelength ranges. Here, an additional periodic phase (APP) from order/disorder alignment is proposed to meet the phase-matching condition in arbitrary nonlinear crystals and demonstrated from the visible region to the deep-ultraviolet region (e.g., LiNbO3 and quartz). Remarkably, pioneering 177.3-nm coherent output is first obtained in commercial quartz crystal with an unprecedented conversion efficiency above 1‰. This study not only opens a new roadmap to resuscitate those long-neglected nonlinear optical crystals for wavelength extension, but also may revolutionize next-generation nonlinear photonics and their further applications.

Imaging flow cytometry allows image-activated cell sorting (IACS) with enhanced feature dimensions in cellular morphology, structure, and composition. However, existing IACS frameworks suffer from the challenges of 3D information loss and processing latency dilemma in real-time sorting operation. Herein, we establish a neuromorphic-enabled video-activated cell sorter (NEVACS) framework, designed to achieve high-dimensional spatiotemporal characterization content alongside high-throughput sorting of particles in wide field of view. NEVACS adopts event camera, CPU, spiking neural networks deployed on a neuromorphic chip, and achieves sorting throughput of 1000 cells/s with relatively economic hybrid hardware solution (~$10 K for control) and simple-to-make-and-use microfluidic infrastructures. Particularly, the application of NEVACS in classifying regular red blood cells and blood-disease-relevant spherocytes highlights the accuracy of using video over a single frame (i.e., average error of 0.99% vs 19.93%), indicating NEVACS’ potential in cell morphology screening and disease diagnosis. Existing image-activated cell sorting tools suffer from the challenges of 3D information loss and processing latency in real-time sorting operations. Here, the authors propose a neuromorphic-enabled video-activated cell sorter (NEVACS) framework, which achieves high-dimensional spatiotemporal characterization content and high-throughput sorting of particles.