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Natural killer (NK) cells are thought to play a key role in the successful establishment of a pregnancy by facilitating immunological adaptation of the semi-allogeneic developing embryo. The aim of this study was to explore the cell number, immunophenotypic characteristics, and activities of peripheral blood NK cells in women with repeated implantation failure (RIF). Peripheral blood was obtained from 27 women with RIF and 11 healthy, fertile controls during the middle luteal phase of the menstrual cycle. CD3- CD56+ NK cells were quantified and analyzed by flow cytometry for the expression of cytolytic molecules (granzyme B, granulysin, and perforin) as well as cell surface receptors responsible for NK cell activation or inhibition (NKG2D, NKp30, NKp46, CD158a, CD158b). NK cytotoxicity was measured at three effector-to-target cell ratios. Women with RIF and fertile controls did not differ significantly in the percentage of circulating CD3−CD56+ NK cells, or in the proportions of these cells that expressed granzyme B, granulysin, or perforin. The two groups also did not differ significantly in the proportions of NK cells expressing the receptors NKG2D, NKp30, NKp46, CD158a or CD158b. General linear model analysis showed that NK cytotoxicity increased with effector-to-target cell ratio. However, NK cytotoxicity did not differ significantly between patients with RIF and fertile controls. These results suggest that RIF is not associated with significant alterations in the number or function of peripheral blood NK cells. Keywords: Activating receptor, Inhibitory receptor, NK cytotoxicity, Peripheral blood NK cells, Repeated implantation failure

Arisaematis Rhizoma included in the Chinese Pharmacopoeia is the dried tuber of Arisaema erubescens, A. heterophyllum or A. amurense in the family Araceae. This paper mainly focuses on the classification and summary of the chemical components and structures reported in recent years in the above three varieties of this medicinal material included in the pharmacopoeia, including alkaloids, flavonoids, phenylpropanoids, lignans and benzene ring derivatives, steroids and terpenes, glycosides and esters, etc. Then we reviewed the reported biological activities of these chemical components, including cytotoxicity, antitumor activity, antibacterial activity, nematicidal activity, etc. Although there have been reports on the review of the chemical composition of the medicinal material, the structure and classification of the chemical composition in these reviews are not clear enough. This review provides a basis for the later study of the chemical composition of this medicinal material, especially the identification of the chemical structures. And most of the current reviews on the biological activity of this medicinal material are mainly for the crude extract. This paper mainly summarized the biological activity of related monomer compounds and expected to lay a foundation for the development of novel high-efficiency and low-toxicity active leading compounds from Arisaematis Rhizoma.

Cell behaviors are regulated by a dynamic and complex environment characterized by biophysical, mechanical and biochemical properties. However, most works regulate cell behaviors under static conditions or by external factors. To control cell adhesion and proliferation with a dynamic and mechanical environment, we pattern the surface on self-healing copolymer P(MMA/nBA). The copolymer P(MMA/nBA) with the composition of 48/52 (MMA/nBA) recovers nearly 100% of its original tensile strains after 86 h of recovery from deformation. The physical patterns on P(MMA/nBA) film are obtained over large areas and the size of the hole and the width of connecting bar are in line with the copper grid specifications. The patterned surface tends to be flat after 12 h with almost 75%-80% recovery. Compared with cell incubation on polystyrene flat and patterned surface of P(MMA/nBA) film without self-healing capability, the number and morphology of cells are well manipulated on the patterned surface of self-healing P(MMA/nBA) film. This approach provides a convenient method for dynamically regulating the cell behaviors on the surface of self-healing materials without chemical or biological modifications.

Equilibrium swelling test was employed to determine the swelling responses of Fluororubber (FKM) and Fluorosilicone Rubber (FVMQ) in different types of solvents, and the one-dimensional solubility parameters of FKM and FVMQ were obtained with a range of 17–25 MPa1/2 and 16–20 MPa1/2 respectively. It was attempted to calculate the three-dimensional solubility parameters (HSP) of FKM and FVMQ by using a professional computer software, and a new type of bio-fuel, represented by biodiesel, was further selected as an object in this work to investigate its swellability. Flory-Huggins interaction parameter (χHSP) between FKM, FVMQ and each solvents used in this work was calculated by HSP values, and the results turned out that the swelling ratio (q) decreased with increasing χHSP value. By mathematical fitting, two functional relationships between q and χHSP for FKM and FVMQ were achieved to predict the swelling properties of rubber in fluids. The increasing use of biodiesel with their effect on rubber materials has become an important topic of industrial research. The second components, including ethanol and ethylene glycol, were added into biodiesel with the purpose of cost reduction, which however might cause a critical increase of rubber swelling. One of the possible applications of χHSP values is the prediction or explanation of swelling behavior. Therein, χHSP values between FKM, FVMQ and biodiesel/additive blends were calculated and found that χHSP firstly decreased and then increased with increase of the additive (ethanol and ethylene glycol) content. Taking advantage of this tendency one can predict the swelling properties of rubber products in the biodiesel blends and provide an important reference for such applications in liquid medium.

In search of simple approaches to rationally modulate the single-molecule magnet behaviors in polynuclear lanthanide clusters, a new system containing two structurally closely related rhombus-shaped Dy4 clusters, Dy4(tmhd)4L6(μ3-OH)2·5CH3CN (1) and Dy4(acac)4L6(μ3-OH)2 (2) (HL = 5-(4-ethyoxylbenzylidene)-8-hydroxylquinoline, Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione and Hacac = acetylacetonate), have been obtained by employing two dysprosium β-diketonate salts to react with a bidentate Schiff base ligand (HL). The two Dy4 clusters have similar structures and possess a structure in which four Dy3+ ions remain in a perfect plane with a rhombus-shaped geometric construction. Dynamic magnetic analysis revealed different single-molecule magnet (SMM) behaviors occurs in 1 and 2. Under zero direct-current (dc) field, 1 displays typical SMMs behavior with ΔE/kB = 39.6 K and τ0 = 2.1 × 10−6 s. However, for 2, a peculiar feature of the χ″ versus temperature curves is that more than two peaks that are frequency-dependent are revealed, indicating the occurrence of multifold relaxation processes that lead to two ΔE/kB (31.3 K and 81.6 K) and pre-exponential factors (τ0 = 3.1 × 10−6 s, τ0 = 2.2 × 10−7 s).

Two new Dy2 compounds, namely, [Dy2(dbm)4(H2L)(CH3O)(CH3OH)] (1) and [Dy2(dbm)5(H2L)] (2) (dbm = dibenzoylmethane, H3L = (2E,N′E)-2-(hydroxyimino)-N′-(pyridin-2-ylmethylene)propanehydrazide, based a polydentate Schiff base ligand have been synthesized, structurally and magnetically characterized. The single-crystal X-ray diffraction research show that both compounds 1 and 2 are binuclear structures. The only difference is that two methanol molecules coordinated to Dy(III) ion in 1 instead of a dbm− coordinated to Dy(III) ion in 2. Magnetic property measurements indicate that they exhibit distinct slow magnetic relaxation behaviors (ΔE/kB = 0.87 K for 1 and ΔE/kB = 18.68 K for 2). This work revealed that the different solvent induced slight disparate structural and magnetic behaviors of two Dy2 compounds, which may provide an effective approach for tuning slow magnetization relaxation behaviors in polynuclear Ln-clusters.

Summary Since December 2019, a novel coronavirus SARS-CoV-2 has emerged and rapidly spread throughout the world, resulting in a global public health emergency. The lack of vaccine and antivirals has brought an urgent need for animal model. Human Angiotensin converting enzyme II (ACE2) has been identified as a functional receptor for SARS-CoV-2. In this study, we generated a mouse model expressing human ACE2 (hACE2) using CRISPR/Cas9 knock-in technology. Compared with wild-type C57BL/6 mice, both young and aged hACE2 mice sustained high viral loads in lung, trachea and brain upon intranasal infection. Although fatalities were not observed, interstitial pneumonia and elevated cytokines were seen in SARS-CoV-2 infected- aged hACE2 mice. Interestingly, intragastric inoculation of SARS-CoV-2 was evidenced to cause productive infection and lead to pulmonary pathological changes in hACE2 mice. Overall, this animal model described here provides a useful tool for studying SARS-CoV-2 transmission and pathogenesis, and evaluating COVID-19 vaccines and therapeutics., Graphical Abstract, Highlights ● Human ACE2 knock-in mice were generated using CRISPR/Cas9 technology ● SARS-CoV-2 leads to robust replication in lung, trachea and brain ● SARS-CoV-2 causes interstitial pneumonia and elevated cytokine in aged hACE2 mice ● High dose of SARS-CoV-2 can establish infection via intragastric route in hACE2 mice, The COVID-19 pandemic has brought an urgent need for small animal models. Here, Sun et al. established an ACE2 humanized mouse by CRISPR/Cas9 knock-in technology. This hACE2 mice are susceptible to SARS-CoV-2 infection upon intranasal inoculation, and the resulting pulmonary infection and pathological changes resemble those observed in COVID-19 patients.

Equilibrium swelling measurement was employed to correlate the Hildebrand (one-dimensional) solubility parameter (δ) of styrene butadiene rubber (SBR) with using different kinds of solvents. The δ was estimated to be a range from 17 MPa1/2 to 19 MPa1/2. It was attempted to calculate the three-dimensional solubility parameter (HSP) of SBR by inputting the swelling data into a professional software program, and the output results were δd = 18.0 MPa1/2, δp = 2.9 MPa1/2 and δH = 2.3 MPa1/2. A new Flory-Huggins interaction parameter (χHSP) between SBR and solvents was calculated by HSP values for the purpose of better predicting rubber swelling responses. The results turned out that the swelling ratio (q) increased with a decrease of χHSP value, showing a roughly linear relationship. Furthermore, a correlation index relating to χHSP value was introduced and mathematical fitted as a functional equation in this work. By using this equation, it is easy to characterize the relative interactions between SBR and each ingredient involved in the formulation and make a pre-screening of the candidate additives for the formula design. Taking advantage of this method one can response better to the challenges in selecting the most suitable additives and replacing the outdated ones by the new emerging ones, bio-sourcing with environmentally friendly ones in particular.

The physical and chemical characteristics of suspended sediment in Waizhou reach are studied.The particle size is between 0.005-0.75mm.The pH value of sediment sample is 7.1.The desorption experiment after adsorbing total nitrogen(TN) and total phosphorus(TP) saturated was carried out.The experimental results show the desorption of sediment on TN and TP reaches basic equilibrium about 8h.Desorption capacity decreases with the increase of sediment concentration.Desorption process is completed by two steps.The first step is physical desorption process quickly.The second step is chemical desorption and belongs to the process of slow response.Using the Langmuir model can better simulate the process of desorbing.The correlation coefficients of fitting with TN and TP are above 0.8 and 0.75 respectively.The higher the sediment concentration, the better fitting effect.

The modeling method of fiber-reinforced composites by state-based peridynamics was studied. The one-parameter nonlinear constitutive model was used to get the nonlinear relationship between force vector state and deformation vector state. Then the governing equation for laminate with nonlinear inplane behavior was built. A compensation modification method was also proposed to reduce the surface effects. A scalar function was introduced in the equation of force vector state in order to describe the damage. After the proposed compensation modification method was verified to reduce strain energy error of particles in the boundary region effectively, both unidirectional and orthotropic composite panels under uniaxial tension load were modeled. The resulting stress-strain curves fit well with the test data. Also, progressive damage analysis of composite panels with a center-hole was carried out, and the corresponding damage results agreed well with the experimental and simulating results of a relevant published research.

Sediment has the function of adsorption and desorption of the nitrogen in water body. This study provides the theoretical basis of calculating the nitrogen content discharged into the Poyang Lake. The results show the nitrogen adsorption of sediment reaches balance basically in about 4~ 6h, the adsorption capacity is increased with the increment of the initial concentration of nitrogen, and decreased with the increment of sediment conentration.The isothermal adsorption of nitrogen by sediment can be fitted preferably by Henry and Langmuir equation.The adsorption and desorption process can be fitted by Langmuir equation.The nitrogen desorption of sediment reaches balance basically in about 8~14h.The nitrogen desorption capacity of sediment is decreased with the increment of sediment concentration.