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Multiplexed intracellular detection is desirable in biomedical sciences for its higher efficiency and accuracy compared to the single-analyte detection. However, it is very challenging to construct nanoprobes that possess multiple fluorescent signals to recognize the different intracellular species synchronously. Herein, we proposed a novel dual-excitation/dual-emission upconversion strategy for multiplexed detection through the design of upconversion nanoparticles (UCNP) loaded with two dyes for sensitization and quenching of the upconversion luminescence (UCL), respectively. Based on the two independent energy transfer processes of near-infrared (NIR) dye IR845 to UCNP and UCNP to visible dye PAPS-Zn, ClO− and Zn2+ were simultaneously detected with a limit of detection (LOD) of 41.4 and 10.5 nM, respectively. By utilizing a purpose-built 830/980 nm dual-laser confocal microscope, both intrinsic and exogenous ClO− and Zn2+ in live MCF-7 cells have been accurately quantified. Such dual-excitation/dual-emission ratiometric UCL detection mode enables not only monitoring multiple intracellular analytes but also eliminating the detection deviation caused by inhomogeneous probe distribution in cells. Through modulation of NIR dye and visible dye with other reactive groups, the nanoprobes can be extended to analyze various intracellular species, which provides a promising tool to study the biological activities in live cells and diagnose diseases.

Lanthanide (Ln3+ )-doped luminescent nanoparticles (NPs) with emission in the second near-infrared (NIR-II) biological window have shown great promise but their applications are currently limited by the low absorption efficiency of Ln3+ owing to the parity-forbidden 4f→4f electronic transition. Herein, we developed a strategy for the controlled synthesis of a new class of NIR-II luminescent nanoprobes based on Ce3+ /Er3+ and Ce3+ /Nd3+ co-doped CaS NPs, which can be effectively excited by using a low-cost blue light-emitting diode chip. Through sensitization by the allowed 4f→5d transition of Ce3+ , intense NIR-II luminescence from Er3+ and Nd3+ with quantum yields of 9.3 % and 7.7 % was achieved, respectively. By coating them with a layer of amphiphilic phospholipids, these NPs exhibit excellent stability in water and can be exploited as sensitive NIR-II luminescent nanoprobes for the accurate detection of an important disease biomarker, xanthine, with a detection limit of 32.0 nm.

Approximately 20% of multiple myeloma (MM) are caused by a chromosomal translocation t (4; 14) that leads to the overexpression of the nuclear receptor binding SET domain-protein 2 (NSD2) histone methyltransferase. NSD2 catalyzes the methylation of lysine 36 on histone H3 (H3K36me2) and is associated with transcriptionally active regions. Using high-throughput screening (HTS) with biological analyses, a series of 5-aminonaphthalene derivatives were designed and synthesized as novel NSD2 inhibitors. Among all the prepared compounds, 9c displayed a good NSD2 inhibitory activity (IC50 = 2.7 μM) and selectivity against both SET-domain-containing and non-SET-domain-containing methyltransferases. Preliminary research indicates the inhibition mechanism of compound 9c by significantly suppressed the methylation of H3K36me2. Compound 9c specifically inhibits the proliferation of the human B cell precursor leukemia cell line RS4:11 and the human myeloma cell line KMS11 by inducing cell cycle arrest and apoptosis with little cytotoxicity. It has been reported that the anti-cancer effect of compound 9c is partly achieved by completely suppressing the transcriptional activation of NSD2-targeted genes. When administered intraperitoneally at 25 mg/kg, compound 9c suppressed the tumor growth of RS4:11 xenografts in vivo and no body weight loss was detected in the tested SCID mice.

We have designed and synthesized a series of two-dimensional materials featuring with a (3,6)-connected kgd layer, in which an unprecedented anionic Cu6I7– cluster was first trapped through a cation-induced synthetic strategy. The emission colors of these cluster-based luminophores gradually shift from blue to yellow as the monovalent cations (Li+, Na+, NH4+, K+, TEA+) located between the neighboring layers changed. SCXRD analyses discover that the variation of the emission may be attributed to the transformation of the hourglass-shaped Cu6I7– cluster. The bright, tunable, and broad luminescent emissions make them promising candidates as phosphors for light-emitting diodes (LEDs). Particularly, compound 1-TEA emitting intensive yellow light with high luminescence quantum efficiency (QY = 79.9%) shows extremely high thermal, pH, organic solvent, and mechanical photostabilities. By employing it as a yellow phosphor, we fabricate a series of white lighting materials with high color rendering index (CRI).

Acute myocardial infarction (AMI) is one of the leading causes of death around the world. An early and accurate diagnosis of AMI is critical to reduce the mortality rate. As an important cardiac biomarker, creatine kinase (CK) has been used in the clinical diagnosis of AMI. However, it still remains a great challenge to realize highly sensitive and selective CK detection in blood specimens. Herein, we have developed an ultrasensitive platform for the detection of CK activity based on time-resolved (TR) luminescent lanthanide metal-organic framework nanoprobes (

Intracellular detection is highly desirable for biological research and clinical diagnosis, yet its quantitative analysis with noninvasivity, sensitivity, and accuracy remains challenging. Herein, a near‐infrared (NIR) dual‐excitation strategy is reported for ratiometric intracellular detection through the design of dye‐sensitized upconversion probes and employment of a purpose‐built NIR dual‐laser confocal microscope. NIR dye IR808, a recognizer of intracellular analyte hypochlorite, is introduced as energy donor and Yb,Er‐doped NaGdF4 upconversion nanoparticles are adopted as energy acceptor in the as‐designed nanoprobes. The efficient analyte‐dependent energy transfer and low background luminescence endow the nanoprobes with ultrahigh sensitivity. In addition, with the nonanalyte‐dependent upconversion luminescence (UCL) excited by 980 nm as a self‐calibrated signal, the interference from environmental fluctuation can be alleviated. Furthermore, the dual 808/980 nm excited ratiometric UCL is demonstrated for the quantification of the level of intracellular hypochlorite. Particularly, the intrinsic hypochlorite with only nanomolar concentration in live MCF‐7 cells in the absence of exogenous stimuli is determined. Such an NIR dual‐excitation ratiometric strategy based on dye‐sensitized UCL probes can be easily extended to detect various intracellular analytes through tailoring the reactive NIR dyes, which provides a promising tool for probing biochemical processes in live cells and diagnosing diseases., Near‐infrared (NIR) dye‐sensitized upconversion nanoprobes are designed for intracellular detection with high sensitivity and accuracy via a purpose‐built NIR dual‐laser confocal microscope system, providing a useful tool to study biological activities in live cells.

The effects of veneer orientation and loading direction on the mechanical properties of bamboo-bundle/poplar veneer laminated veneer lumber (BWLVL) were investigated by a statistical analysis method. Eight types of laminated structure were designed for the BWLVL aiming to explore the feasibility of manufacturing high-performance bamboo-based composites. A specific type of bamboo species named Cizhu bamboo (Neosinocalamus affinis) with a thickness of 6 mm and diameter of 65 mm was used. The wood veneers were from fast-growing poplar tree (Populus ussuriensis Kom.) in China. The bamboo bundles were obtained by a mechanical process. They were then formed into uniform veneers using a one-piece veneer technology. Bamboo bundle and poplar veneer were immersed in water-soluble phenol formaldehyde (PF) resin with low molecular weight for 7 min and dried to MC of 8–12 % under the ambient environment. All specimens were prepared through hand lay-up using compressing molding method. The density and mechanical properties including modulus of elasticity (MOE), modulus of rupture (MOR), and shearing strength (SS) of samples were characterized under loading parallel and perpendicular to the glue line. The results indicated that as the contribution of bamboo bundle increased in laminated structure, especially laminated on the surface layers, the MOE, MOR and SS increased. A lay-up BBPBPBB (B-bamboo, P-poplar) had the highest properties due to the cooperation of bamboo bundle and poplar veneer. A higher value of MOE and MOR was found for the perpendicular loading test than that for the parallel test, while a slightly higher SS was observed parallel to the glue line compared with perpendicular loading. Any lay-up within the homogeneous group can be used to replace others for obtaining the same mechanical properties in applications. These findings suggested that the laminated structure with high stiffness laid-up on the surface layers could improve the performance of natural fiber reinforced composites.

A modified moisture diffusion equation fits the plots between moisture ratio and time.The moisture sorption rate of grain is showed by differential form of d ( M t ) / dt .Moisture diffusivity in wheat tends to increase with temperature raise at certain RH. Wheat samples with low (4.97-6.08%), normal (10.11-11.04%), and high (20.7-22.72%) initial moisture content (IMC, wet basis) were used to determine the rate of moisture adsorption by the gravimetric method at 10, 20, 25, 30, and 35?C under 65%, 86%, and 100% relative humidity (RH), respectively. A moisture diffusion equation was modified to fit the relationship between the moisture ratio of samples and exposure time. From 65% to 100% RH, the IMC of wheat samples was inversely related to the moisture adsorption rate at temperatures from 10 to 35?C. Moisture adsorption rates of samples increased with increasing temperatures. The moisture adsorption rate of samples with the same IMC increased with increasing RH at a given temperature. A single wheat kernel was considered geometrically to be a finite homogeneous slab shape, and the analytical solution of the partial differential equation for moisture diffusion was given. The effective moisture diffusivity was calculated using the slope method by plotting the experimental data in terms of ln (MR) versus rewetting time. In the range of 10-35?C, the effective moisture adsorption diffusivity of wheat kernels with normal moisture was 1.681×10-8-1.516×10-7m2h-1, and their activation energy was 23.651-28.434kJmol-1. For the same IMC, the effective moisture diffusivity of wheat kernels tended to increase with increasing temperature at a given RH, but decreased with an increase in RH at a given temperature. Activation energy and the pre-exponential factor of Arrhenius equation (D0) tended to decrease with increasing RH. With similar initial moisture content, winter wheat and spring wheat exhibited similar effective moisture diffusivity.

In this paper, we investigate the non-constant stationary solutions of a general Gause-type predator-prey system with self- and cross-diffusions subject to the homogeneous Neumann boundary condition. In the system, the cross-diffusions are introduced in such a way that the prey runs away from the predator, while the predator moves away from a large group of preys. Firstly, we establish a priori estimate for the positive solutions. Secondly, we study the non-existence results of non-constant positive solutions. Finally, we consider the existence of non-constant positive solutions and discuss the Turing instability of the positive constant solution.

A smart cooling-aeration (SCA) system was developed and tested for cooling bulk paddy stored in concrete silos in a south-subtropical depot of Guangzhou, China. Besides lowering the grain temperature with natural cold air during winter months, the cooling-aeration operation was also required to minimize grain moisture content loss, as well as the fan noise nuisance to nearby residents. Based on the grain and ambient air condition, the SCA system used the collected information in Aeration Window Model (AWM) for optimal control of aeration fans. The AWM was based on the CAE adsorptive equation and equilibrium absolute humidity curve. The SCA system was tested in two concrete silos of 650 tonnes in Guangzhou (22°44′N, 113°30′E) from 7 December 2018 to 5 March 2019. The system was set to turn on the fans when the temperature of grain bulk was 3 °C higher than the ambient air temperature and the equilibrium absolute humidity of grain for adsorption was above the absolute humidity of the ambient air. The grain temperature in one silo decreased by 10.3 °C after 97.8 h of aeration. The unit energy consumption by one 5.5-kW centrifugal fan was 0.063 k W h t ∙ ° C - 1 . The grain temperature was lowered by 9.2 °C in 106.5 h in the second silo with the unit energy consumption of 0.031 k W h t ∙ ° C - 1 by a 2.2-kW centrifugal fan. The unit energy consumption for both silos were 52−77% lower than the lowest “typical” value (0.132 k W h t ∙ ° C - 1 ) in similar type of silos in the region when cooling aeration is manually controlled. Compared to the 650 tonne paddy rice in the control silo with a 15 kW aeration fan, the grain moisture content, the total milled rice yield and grain processing quality was unchanged by the smart cooling aeration with smaller kW aeration fans.

Two novel microporous metal–organic frameworks were obtained by combination of a tetratopic linker and linear trinuclear cobalt(II) and cadmium(II) cluster subunits. The complexes exhibit unprecedented topological features and unique magnetic and photoluminescence properties.

Rattle structure is a topic of great interest in design and application of nanomaterials due to the unique core@void@shell architecture and the integration of functions. Herein, we developed a novel “ship-in-a-bottle” method to fabricate upconverting (UC) luminescent nanorattles by incorporating lanthanide-doped fluorides into hollow mesoporous silica. The size of nanorattles and the filling amount of fluorides can be well controlled. In addition, the modification of silica shell (with phenylene and amine groups) and the variation of efficient UC fluorides (NaYF4:Yb,Er, NaLuF4:Yb,Er, NaGdF4:Yb,Er and LiYF4:Yb,Er) were readily achieved. The resulting nanorattles exhibited a high capacity and pH-dependent release of the anti-cancer drug doxorubicin (DOX). Furthermore, we employed these nanorattles in proof-of-concept UC-monitoring drug release by utilizing the energy transfer process from UC fluorides to DOX, thus revealing the great potential of the nanorattles as efficient cancer theranostic agent.

A doubly interpenetrated microporous indium based metal–organic framework was solvothermally synthesized, in which cage-like pores and one-dimensional channels coexist. Due to its flexible nature, the complex exhibits a novel dynamic response to N2, Ar and CO2 sorption. Furthermore, the material shows a high H2 uptake capacity.