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Accurate targeting and low side effects are crucial for tumor theranostics. Herein, an in situ targeted therapy strategy which relies on a photothermally triggered theranostics nanoplatform is proposed. Taking advantage of spherical nucleic acids, black phosphorus nanosheets and zinc porphyrin metal‐organic framework (PPF‐1) nanosheets are programmed by DNA hybridization to result in a "sandwich" like structure. Its phase‐transition temperature is finely tuned by altering the strand length and the proportion of (A + T) and (C + G) of the oligonucleotides. The superstructure can disassemble during photothermal therapy (PTT) process once the temperature reaches the melting point (Tm) of oligonucleotides duplex. Since the relief of fluorescence resonance energy transfer, the photothermally triggered photodynamic therapy can be realized under the irradiation of near‐infrared laser. In turn, the enhanced singlet oxygen generation downregulates the heat shock proteins and thus improves the effect of PTT. Furthermore, the behaviors of superstructures in living cells and animals are elaborated by fluorescence and magnetic resonance imaging, and the in vivo therapy efficiency is also evaluated. This superstructure may establish a multiple synergistic platform for advanced cancer theranostics. [ABSTRACT FROM AUTHOR]

To investigate the interaction between low-carbon low-silicon Al-killed molten steel and the refractory materials employed in refining ladles, the study focused on the interface reaction between molten steel with a composition of Fe-0.03C-0.01Si-0.2Mn-0.03Al (wt%) and the four types of refractory materials used in different positions of refining ladles at 1873 K. The results show that different interface layers form after 60 min of contact between the refractory materials and the molten steel. The MgO-C refractory generates a dense MgO layer, the MgO-Al2O3 refractory produces a (Fe, Mg)Al2O4 layer, the Al2O3-SiC refractory forms a Mg Al2O4 layer rich in Si, and the MgO-Al2O3-C refractory generates a MgAl2O4 spinel layer. The average content of Mg at the interface decreases in the following order: MgO-C, MgO-Al2O3-C, Al2O3-SiC and MgO-Al2O3 refractory, and SiC available in Al2O3-SiC refractory supplies more Si to the interface. The thermodynamic simulation is consistent with the actual results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photothermal convertible materials temperature controlled PTT were prepared. • The equilibrium temperature can be tuned with a step size of 0.5 °C during 30–80 °C. • The photothermal irradiation wavelength can be turned during 808–1064 nm. Mild photothermal therapy (PTT) at temperature window of 42–47 °C has received tremendous attention for its minor heat damage to the normal tissues. As the critical step in mild PTT process, accurate temperature control still suffers from the complex environment of tumor tissue. Here we proposed a wavelength-equilibrium temperature dual-tunable temperature-controlled PTT strategy based on oligonucleotides (OGN) assembled Au nanomaterials. The NIR absorption of the Au nanomaterials enhances with the plasmon coupling caused by the OGN assembly, and rapidly reverts upon the melting temperature (Tm) of the OGN in the PTT process. The temperature-dependent NIR absorption enables the Au assembly geometry to be exempt from the external disturbance and maintain the equilibrium temperature at the Tm of the OGN. In vivo experiments have confirmed that the OGN assembled Au nanomaterials can effectively ablate the tumor with minimal side effects. [ABSTRACT FROM AUTHOR]

Different reaction conditions or reaction sequences are critical problems to be solved in synthetic chemistry research. Calculating possible reaction paths with quantum chemistry methods could effectively drive the development of chemical synthesis. Here, we take the synthesis of thiopental (or pentothal sodium), an ultra‐short‐acting general anesthetic that induces hypnosis and anesthesia, as an example. Different synthetic routes for this compound have been reported in the literature, but detailed information such as the alkylation sequence is illusive. In this work, we revisited the thiopental synthesis path with combined computational prediction and experimental validation. We explored the reaction mechanism of each putative elementary step with density functional theory (DFT) calculations. Our computations show that two different alkylation paths (with either 2‐bromopentane or bromoethane) are both possible. However, the reaction order has a significant impact on the amount of by‐products in the synthesis product. The subsequent experiments validated the predicted alkylation sequence from DFT calculations. We further showed that EtONa/EtOH is much better than NaH/EtOH to produce thiopental through thiourea's reaction with 2‐ethyl‐2‐(1‐methylbutyl) diethyl malonate with a higher yield of the target product. The proposed synthetic path gives a total yield of 66%, higher than the literature reported. Therefore, the computation‐driven synthesis of drug molecules provides new insight into the synthetic route's appropriate design and optimization of reaction conditions. [ABSTRACT FROM AUTHOR]

Tumor microenvironment responsive photothermal ablation is a noninvasive and accurately targeted approach for cancer therapy. Herein, an intracellular directional assembly strategy for enhanced photothermal therapy (PTT) was realized by using ZIF-8 encapsulated Au nanorod (AuNR) heterostructure as the precursor of photothermal convertible material. The ZIF-8 shell selectively degraded in tumor cells upon the chelation between GSH and Zn2+, while the as-formed Zn(SG) connected the released AuNR in end-to-end fashion. The coating of ZIF-8 shell significantly improves the stability and targeting of AuNR, and the released Zn2+ shielded the GSH binding site on the lateral side of AuNR, increased the plasmonic coupling efficiency of AuNR assembly geometer. This design enabled atomic-economical, efficient and low-side effect targeted photothermal therapy through the effective integration of heterostructures. • ZIF prefers to degrade by chelation with GSH than protonation with weak acids. • The as-formed Zn(SG) n complexes assembled AuNRs in end-to-end fashion. • Axial assembly of AuNR significantly enhanced the NIR absorbance. [ABSTRACT FROM AUTHOR]

The lower Yellow River is characterized by frequent channel avulsion and flooding during the late Holocene, which not only shaped the geomorphic landscape of the North China Plain, but also modified the preexisting drainage network and affected human settlement pattern. The channel evolution of the lower Yellow River during historical periods of China has been well known from documentary records. However, it is still unclear about the drainage pathway of the river during the archaic period of Chinese history. Here we show sedimentary evidence for a dramatic channel displacement of the lower Yellow River about 3000–2600 years ago. Our multi-proxy analyses indicate that the first prehistoric diversion of the Yellow River occurred around 3000 yr B.P. and the river flowed northward into the Bohai Sea through the foreland depression along the eastern foothill of the Taihang Mountains. Frequent floods thereafter not only led to the widespread infilling of depressions in the lower reaches of the Yellow River and thus accelerated the formation of the North China Plain, but also drove humans to migrate from the piedmont area of the Taihang Mountains to the hinterland of the central North China Plain. • Sedimentary evidence of Yellow River flow into Bohai Sea via Taihang Mountains. • Between 3 and 2.6 kyr BP, Yellow River Flowed through Taihang Mountains' Front Basin. • After 3 kyr BP, Yellow River course changes accelerated North China Plain Formation. [ABSTRACT FROM AUTHOR]

Soil microbial functional potential is important for productivity and sustainable agricultural development; however, the potential response of soil nutrient cycling to different fertilisation regimes remains unclear, especially in perennial tree soils. Here, metagenomic sequencing was applied to investigate the soil microbial functional profiles of carbon (C), nitrogen (N), and phosphorus (P) cycling after seven years of chemical, organic, and biofertiliser fertilisation in walnut (Juglans regia L.) orchard. Microbial communities balanced their elemental requirements through selective degradation. The highest relative abundance of genes for labile C-degradation (amyA , malZ , and xylH) was found under chemical fertilisation (F), whereas the metabolic potential for soil N and P cycling was less affected by F. Compared with CK and F, the addition of organic and/or biofertiliser significantly reduced the relative abundances of labile and recalcitrant C-degradation genes (e.g., chi , and xylH) but promoted the processes of N degradation (GDH1 , GDH2 , ureA , glnA , and arcC), DNRA (nrfA , napB , and napC), organic P mineralisation (phy), P solubilisation (gcd), and P uptake and transport (phnD) in walnut soils. At the phylum level, most C, N, and P cycle-related microbes were similar, and applying biofertiliser remarkably improved the relative abundances of Proteobacteria and Firmicutes involved in C, N, and P cycling processes. Furthermore, soil TN and AP were key limiting macronutrients for regulating the pathways of soil C, N, and P cycles and microbial taxa. C, N, and P cycle-related genes were tightly coupled through synergetic or antagonistic interactions, especially metabolic pathways encoded by glnA , mmsA , phy, and appA. Overall, our results provide a biological perspective on the microbial genetic potential of soil C, N, and P cycles in perennial crops and explore their interactions under different long-term fertilisation regimes in a walnut orchard. [Display omitted] • The effect of fertilisation was stronger for the C cycle in soil than for the N and P cycles in walnut orchards. • Organic fertiliser or biofertiliser boosted the conversion and cycling of C, N, and P. • TN and AP were the most important environmental factors in regulating C, N, and P cycles. • C, N, and P cycles were tightly coupled, and N and P reactions were essential for C cycling. [ABSTRACT FROM AUTHOR]

As an excellent NH 3 -SCR catalyst, Fe-ZSM-5 suffered from its inferior performance at lower temperature region. Efforts have been made to improve the low/medial-temperature reaction rate of it. In this work, a sequential reaction strategy relied on a core-shell structure zeolite with Fe-ZSM-5 core and ceria loaded mesoporous-silica shell was proposed. It was confirmed that a considerable portion of NO was pre-oxidized to NO 2 when the mixture gas passed through the ceria loaded mesoporous silica shell which leads to the occurrence of fast-SCR process on Fe-ZSM-5 core. As expected, the ceria loaded mesoporous-silica shell acted as an oxidation reactor for NO and the Fe-ZSM-5 core was the real location where fast-SCR took place. To emphasize such a sequential reaction, the process of diffusion and the necessity of ceria loaded mesoporous silica shell were further discussed and confirmed by TPD and in situ DRIFTS. [ABSTRACT FROM AUTHOR]

A self-assembly composite of graphene-pyrroloquinoline quinone (PQQ) was fabricated and modified on glassy carbon electrode (GCE) for sensitive detection of nicotinamide adenine dinucleotide (NADH). Chitosan (CTS) was applied to disperse graphene to form a stable robust film on GCE. A synergistic effect between PQQ and graphene was observed during the electrocatalytic oxidation of NADH, with about 260 mV reduction in the oxidation potential and 2.5-fold increase in the oxidation current compared with those on the bare GCE. The electrochemical sensors based on the modified electrodes allowed the detection of NADH with a good linear dependence from 0.32 to 220 µM with a high sensitivity of 0.421 µA µM −1 cm −2 and a low detection limit of 0.16 µM (S/N=3). It could also eliminate the interference of electroactive substances like ascorbic acid (AA), uric acid, and dopamine and its derivatives. The outstanding performances of graphene-PQQ/CTS composite capable of improving the electrical conductivity and accelerating the electron transport suggested its promising applications for design of different graphene based composites used in electrochemical sensing and energy fields. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks possess tremendous potential in biomedical areas for their particular structure. In this study, the authors explored Fe2+-adsorbed nanoscaled zeolitic imidazolate framework-8 (ZIF-8) for in vivo multimodal imaging of cancerous cells for early diagnosis of target cancers. The observations demonstrate that adding Fe2+ into the suspension of ZIF-8 can neutralize the alkalinity and lower toxicity, while the Fe2+-adsorbed ZIF-8 can readily transform to fluorescence ZnO and super paramagnetic Fe3O4 under the synergistic reaction of ROS, GSH, and acids. It is evident that the formation of the nanoclusters ZnO and Fe3O4 only occurred in cancerous cells and does not take place in normal cells, which can be attributed to the different ROS levels and specific micro-environment in tumor and normal cells. This raises the possibility for the Fe2+-adsorbed zeolitic imidazolate frameworks to act as promising agents for the in vivo multimodal imaging of cancers in their early stage. [ABSTRACT FROM AUTHOR]

Although various combinations of organic-inorganic fertilizers can enhance plant yields, the effects of different fertilization regimes on the associations between rhizosphere soil microorganisms and plant productivity are poorly understood. In this study, we investigated the rhizosphere soil microbial composition and structure and the relationships among rhizospheric microorganisms, soil properties, and yield in a walnut (Juglans regia L.) orchard after 7 years of applying different fertilization regimes. The combinations of organic and inorganic fertilizers were found to enhance walnut yield, soil quality index (SQI), and soil biodiversity (bacterial and fungal) (P < 0.05). The soil microbial community composition and co-occurrence networks of rhizosphere soil (RS) and bulk soil (BS) showed different responses to fertilization. Bacillus and Pseudomonas were mainly enriched in RS, whereas Fusarium was significantly more abundant in BS (P < 0.05) under a combined chemical fertilizer, organic fertilizer, and biofertilizer treatment (F + O + BO). Network analysis revealed that organic fertilizer and biofertilizer reduced the competition and network complexity among rhizosphere microbial communities (edges: RS = 388, BS = 967; modularity: RS = 0.790, BS = 0.834). Furthermore, SQI, microbial diversity, and network complexity were significantly correlated with walnut yield (P < 0.01), among which SQI explained the highest proportion of the variation in yield (SOI: RS = 78.02%; BS = 81.18%). In addition, both yields and soil microbial community composition were significantly affected by pH, SOM, TN, and SMBN. Collectively, these findings have important implications for our understanding of the relationship between woody plants and rhizospheric microorganisms. [Display omitted] [ABSTRACT FROM AUTHOR]

Fe-ZSM-5 with particle size of 200 nm was coated with a tiny silicalite-1 shell via secondary hydrothermal crystallization in order to improve the hydrophobicity of Fe-ZSM-5 on NH 3 -SCR. The formation mechanism, adsorption performance and SCR activity of the core–shell zeolites were investigated in this paper. During the secondary hydrothermal crystallization procedure, the different content of silicon source (TEOS) led to the different morphologies of the shell. Comparing to Fe-ZSM-5, the core–shell zeolites have higher activities on NH 3 -SCR and hardly impacted with H 2 O. For a further study, UV–Vis DRS, TPD, in situ FTIR and TG were combined and suggested that the differences between Fe-ZSM-5 and core–shell zeolites on NH 3 -SCR performance can be attributed to the adsorption of NO x on silicalite-1, Fe species transformation during secondary hydrothermal crystallization and the hydrophobicity of silicalite-1. [ABSTRACT FROM AUTHOR]

Developing fluorescent probes to detect reactive oxygen species (ROS) is imperative to understanding the vital roles of ROS in various signaling and pathological processes. In this work, UiO-66-NH 2 could be readily utilized as self-calibrating nanoprobe for selective detection and bioimaging of hypochlorite. Under the excitation of 400 nm, UiO-66-NH 2 featured an emission at 432 nm and a new emission at 533 nm appeared after the addition of ClO-. Besides, the emission intensity of 533 nm increased with the incremental amount of ClO-. By using the ratio I 533 nm /I 432 nm as detection signal, UiO-66-NH 2 could discriminate ClO- with high performance. The linear working range towards ClO- is 0.1–150 μM and the detection limit is 63.8 nM. In contrast to most other ratiometric sensors fabricated by physical entrapment methods, UiO-66-NH 2 has the obvious advantage of effectively avoiding the worry of leakage of fluorophores from the nanomaterial matrix of sensors leading to erroneous measurements. Other amino-group functionalized MOF-based sensors such as MIL-53-NH 2 (Al) and MIL-101-NH 2 (Fe) exhibited similar fluorescence response toward ClO- as UiO-66-NH 2. This work raises the possibility to develop highly specific and efficient probe for ClO- detection in vivo or in living cells and presents a new insight into ratiometric sensors. [Display omitted] • UiO-66-NH 2 shows a new emission at 533 nm after reacting with ClO-. • By using I 533nm /I 432nm as signal, UiO-66-NH 2 could be used as a self-calibrating nanoprobe for the detection of ClO-. • UiO-66-NH 2 exhibits a wide linear range 0.1-150 μM and a low detection limit 63.8 nM. • Other amino-group functionalized MOF-based sensors such as MIL-53-NH 2 (Al) and MIL-101-NH 2 (Fe) display similar performance. [ABSTRACT FROM AUTHOR]

Developing fluorescent probes to detect reactive oxygen species (ROS) is imperative to understanding the vital roles of ROS in various signaling and pathological processes. In this work, UiO-66-NH 2 could be readily utilized as self-calibrating nanoprobe for selective detection and bioimaging of hypochlorite. Under the excitation of 400 nm, UiO-66-NH 2 featured an emission at 432 nm and a new emission at 533 nm appeared after the addition of ClO-. Besides, the emission intensity of 533 nm increased with the incremental amount of ClO-. By using the ratio I 533 nm /I 432 nm as detection signal, UiO-66-NH 2 could discriminate ClO- with high performance. The linear working range towards ClO- is 0.1–150 μM and the detection limit is 63.8 nM. In contrast to most other ratiometric sensors fabricated by physical entrapment methods, UiO-66-NH 2 has the obvious advantage of effectively avoiding the worry of leakage of fluorophores from the nanomaterial matrix of sensors leading to erroneous measurements. Other amino-group functionalized MOF-based sensors such as MIL-53-NH 2 (Al) and MIL-101-NH 2 (Fe) exhibited similar fluorescence response toward ClO- as UiO-66-NH 2. This work raises the possibility to develop highly specific and efficient probe for ClO- detection in vivo or in living cells and presents a new insight into ratiometric sensors. [Display omitted] • UiO-66-NH 2 shows a new emission at 533 nm after reacting with ClO-. • By using I 533nm /I 432nm as signal, UiO-66-NH 2 could be used as a self-calibrating nanoprobe for the detection of ClO-. • UiO-66-NH 2 exhibits a wide linear range 0.1-150 μM and a low detection limit 63.8 nM. • Other amino-group functionalized MOF-based sensors such as MIL-53-NH 2 (Al) and MIL-101-NH 2 (Fe) display similar performance. [ABSTRACT FROM AUTHOR]

Ethereum realizes the application of programs on the blockchain through smart contracts and the peer-to-peer transmission of nodes through consensus mechanisms. In this paper, through smart contracts, cache nodes and three-level cache mechanism are proposed, so that users can efficiently obtain contents through three-level cache in a large-scale network environment to speed up response and reduce network burden; what's more, to ensure data integrity and accuracy in the untrusted public Ethereum blockchain, RSA&VT integrity verification methods are also introduced, and a large number of tree shapes are saved through IPFS under the chain structure to verify the content integrity, and only a small portion of the verification credentials and verification results are required to be transmitted in the network. Through experiments, it is proved that the request response time of the three-level caching mechanism is better than the ordinary FIFO cache; the performance of RSA&VT method is also better than the Signature scheme from bilinear maps. [ABSTRACT FROM AUTHOR]

The cylinder-airfoil interaction noise can be reduced by changing the shape of the leading edge of the downstream airfoil. Generally, this way not only can reduce the interaction noise at middle and high frequency, but also can change the peak noise at the low frequency. This study attempts to affect the cylinder-airfoil interaction noise from the perspective of reducing the intensity of the upstream wake shedding vortex. In order to achieve this target, the equally spaced grooves were cut into the upstream cylinder, and the acoustic wind tunnel tests at various incoming velocities (20–60m·s−1) were conducted to compare the interaction noise of cylinder-airfoil (NACA0012) models. It is found that the grooved structure can effectively reduce the peak noise at characteristic frequencies bellow 1000 Hz and the broadband noise in the mid-frequency ranging from 1000 Hz to 3000 Hz, especially for the higher incoming velocity. Thereinto, the peak noise and overall sound pressure level (OASPL) with the grooved cylinder are reduced by 13 dB and 7.2 dB, respectively at the incoming velocity of 60 m·s−1. The numerical simulations based on the large eddy simulation (LES) and Ffowcs Williams–Hawkings (FW-H) acoustic analogy were performed to further reveal the mechanisms of noise reduction when the velocity is 60 m·s−1. The results show that the vortex shedding from cylinder wake is suppressed by the grooved cylinder and the vortex structure at the leading edge of the airfoil is also cut into the small-scale vortex structures by the grooved structure. The pressure fluctuation amplitude and the peak value turbulent kinetic energy in the wake of the grooved cylinder are significantly reduced. In addition, the further spectrum analysis reveals that the weak correlation of the vortex shedding on the grooved cylinder could lead to the suppression of the pressure fluctuation in the cylinder wake, and thereby the interaction noise is significantly reduced. [ABSTRACT FROM AUTHOR]

Although highly porous structure endows MOFs distinctive properties in luminescent sensing, consider each single MOF particle is consisted with a large number of luminescent unit cells, the AIE and ACQ effect would play significant role which is worth studying. In this work we employed some conventional luminescent MOFs (MIL-53(Al), MIL-101(Fe), UiO-66(Zr) and ZIF-8), aimed to indicate how does the structure property impact the detective result. The AIE or ACQ effect was triggered by fine adjusting the particle size or chromophore of MOFs, afterwards, their detective performances were evaluated to reveal the real effect of AIE and ACQ. • AIE and ACQ effect in MOFs' sensing was studied. • AIE or ACQ effect was triggered by adjusting the particle size or chromophore of MOFs. • The effect of internal diffusion was investigated in FITC conjugated MOFs. [ABSTRACT FROM AUTHOR]

Chromium slag is a solid waste of chromium salt production, which contains highly toxic Cr(VI) and significant amounts of valuable metals, such as Fe and Cr. Recycling chromium slag as a raw sintering material in sintering–ironmaking processes can simultaneously reduce toxic Cr(VI) and recover valuable metals. A micro-sintering experiment, compressive strength test, microhardness test, and first-principles calculation are performed to investigate the influence of Cr2O3 on the sintering microstructure and mechanical properties of the silico-ferrite of calcium and aluminum (SFCA) in order to understand the basis of the sintering process with chromium slag addition. The results show that the microstructure of SFCA changes from blocky to interwoven, with further increasing Cr2O3 content from 0 wt% to 3 wt%, and transforms to blocky with Cr2O3 content increasing to 5 wt%. Cr2O3 reacts with Fe2O3 to form (Fe1−xCrx)2O3 (0 ≤ x ≤ 1), which participates in forming SFCA. With the increase in Cr doping concentrations, the hardness of SFCA first decreases and then increases, and the toughness increases. When Cr2O3 content increases from 0 wt% to 3 wt%, the SFCA microhardness decreases and the compressive strength of the sintered sample increases. Further increasing Cr2O3 contents to 5 wt%, the SFCA microhardness increases, and the compressive strength of sintered sample decreases. [ABSTRACT FROM AUTHOR]

• An enhanced serration structure was found to reduce the airfoil aeroacoustic noise with maintains the mechanical properties of the original structure. • The experimental data shows a significant peak noise reduction of nearly 26 dB and a magnitude decrease of more than 10 dB in the overall sound pressure level (OASPL) at a freestream velocity of 20 m/s with the attack angle 0˚. • The turbulent kinetic energy (TKE) value close to the biomimetic airfoil surface is reduced, and the spanwise coherence of the surface pressure fluctuation source weakens. • The phase spectra analysis indicates that the phases of the fluctuation pressure signals beside the center of the two adjacent ridge-like structures are opposite. In general, the serrated blade edge can reduce the aeroacoustic noise of the thin airfoil, but the blade's integrity and pneumatic efficiency cannot be guaranteed. This research proposes a bioinspired ridge-like structure that won't affect the strength of the blade, and it has more potential to be employed as an innovative noise reduction configuration for engineering applications. The experimental data shows a significant peak noise reduction of nearly 26 dB and a magnitude decrease of more than 10 dB in the overall sound pressure level (OASPL) at a freestream velocity of 20 m/s with the attack angle 0˚. Based on the computational fluid dynamic simulation, the mechanism for the noise reduction employing the ridge-like structure is qualitatively and quantitatively examined. In summary, the ridge-like structures on the leading edge may enhance the transition to move an upstream position. Under the synergy of the ridge-like structures on the leading and trailing edges, the turbulent kinetic energy (TKE) value close to the airfoil surface is reduced, and the spanwise coherence of the surface pressure fluctuation source weakens. The phase spectra analysis indicates that the phases of the fluctuation pressure signals beside the center of the two adjacent ridge-like structures are opposite, and therefore the phase interference in the biomimetic airfoil between two adjacent ridge-like structures is significantly enhanced in the frequency range from 100 Hz to 800 Hz. For the biomimetic airfoil described in this paper, the phase interference between adjacent ridge-like structures immediately results in noise. [ABSTRACT FROM AUTHOR]

Registration between remote sensing images has been a research focus in the field of remote sensing image processing. Most of the existing image registration algorithms applied to feature point matching are derived from image feature extraction methods, such as scale-invariant feature transform (SIFT), speed-up robust features (SURF) and Siamese neural network. Such methods encounter difficulties in achieving accurate image registration where there is a large bias in the image features or no significant feature points. Aiming to solve this problem, this paper proposes an algorithm for multi-source image registration based on geographical location information (GLI). By calculating the geographic location information that corresponds to the pixel in the image, the ideal projected pixel position of the corresponding image is obtained using spatial coordinate transformation. Additionally, the corresponding relationship between the two images is calculated by combining multiple sets of registration points. The simulation experiment illustrates that, under selected common simulation parameters, the average value of the relative registration-point error between the two images is 12.64 pixels, and the registration accuracy of the corresponding ground registration point is higher than 6.5 m. In the registration experiment involving remote sensing images from different sources, the average registration pixel error of this algorithm is 20.92 pixels, and the registration error of the image center is 21.24 pixels. In comparison, the image center registration error given by the convolutional neural network (CNN) is 142.35 pixels after the registration error is manually eliminated. For the registration of homologous and featureless remote sensing images, the SIFT algorithm can only offer one set of registration points for the correct region, and the neural network cannot achieve accurate registration results. The registration accuracy of the presented algorithm is 7.2 pixels, corresponding to a ground registration accuracy of 4.32 m and achieving more accurate registration between featureless images. [ABSTRACT FROM AUTHOR]

Ceria-based catalysts exhibit excellent performance at mediate-high temperature in selective catalytic reduction (SCR) of NO with NH 3 . However, their activities are severely restrained in the presence of H 2 O and SO 2 . In this work, Ni–Ce–La composite oxide nanocrystals were synthesized. After sulfation, it showed excellent H 2 O and SO 2 tolerance. The catalysts were studied by inductively coupled plasma (ICP), energy dispersive spectroscopy (EDS), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), temperature-programmed desorption (TPD), in situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS), Brunauer–Emmett–Teller (BET) surface area and thermogravimetry (TG). The H 2 O and SO 2 tolerance of Ce-based catalysts and sulfation mechanism and its effect on the SCR activity were investigated. After sulfation, the increase in proportion of Ce 3+ /(Ce 3+ + Ce 4+ ), the formation of SO 4 2− and the increase of NH 3 adsorptivity all illustrate that sulfation increases the Brönsted acid sites of samples. The mainly reserved Lewis acid sites and the newly formed Brönsted acid sites contribute to the excellent SCR activity. A shrinking core model was proposed to explain the process of sulfation. The reaction process mostly follows L–H mechanism. After sulfation, Ni–Ce–La composite oxide increases NH 3 adsorptivity and remains good NO adsorptivity, which greatly enhances resistance to H 2 O and SO 2 . [ABSTRACT FROM AUTHOR]

Cu-alloyed martensitic heat-resistant steels are considered promising structural materials in advanced ultra-supercritical (USC) plants. In this work, the evolution of Cu-rich particles (CRPs) and Laves phases (LPs) in the G115 steel and the corresponding effects on microstructure recovery were systematically studied via interrupted creep. Most CRPs precipitated within the lath interior during tempering process and started to precipitate along the lath boundaries during creep. The interior-precipitated CRPs were gradually decomposed due to dislocation cutting effect, resulting in the decrease of their number density. The precipitation of CRPs along the lath boundaries could induce the heterogeneous precipitation of LPs owing to the decrease of nucleation barrier. The number density of LPs rapidly increased during the transient stage but started to decrease during the steady-stage stage due to the coarsening behaviors of Ostwald ripening and swallowing adjacent M 23 C 6 particles. The larger size and decreased number density of LPs and CRPs considerably weakened their pinning force for dislocations and boundaries, leading to an intense microstructure recovery during the accelerated stage. Eventually, the large area of recrystallized grains and subgrains with low hardness and the accumulation of cavities resulted in the creep fracture. • Intergranular Cu-rich particles facilitate nucleation of Laves phases due to chemical driving force and interfacial energy. • Both the dislocation-cutting driving dissolution and Ostwald ripening contribute to the coarsening of Cu-rich particles. • The interaction in precipitation behavior of Cu-rich particles and Laves phases can affect microstructural recovery. [ABSTRACT FROM AUTHOR]

• A facile etching of silver from GSNBs could be modulated by carboxylates. • The –COOH number and distribution inner molecule matters for modulation efficiency. • The paradoxical effect of pH has been well explained. Nanoalloys have been well attracted due to their unique physiochemical and optical properties. Although some nanoalloys are known to remain stable in complex biological environment because of the electron compensation effect (ECE), the effective modulation of ECE has yet to be explored. Here, we have demonstrated that the ECE can be modulated after adsorption of carboxylate on gold silver nanoboxes (GSNBs), accompanied with the release of alloy nanoclusters, as supported by X-ray photoelectron spectroscopy and the electron density difference calculation. Moreover, the modulation efficiency is dependent on the pH of solution and the number of carboxylate groups. Using citrate as a representative, about 80 % silver components of GSNBs can be oxidized and released within 30 min in the presence of H 2 O 2 , producing highly-efficient antibacterial alloy clusters for both in vitro and in vivo applications. These results may offer a deep insight into modulation of intermetallic electron transfer of nanoalloys to develop new and effective antibacterial strategies. [ABSTRACT FROM AUTHOR]

Rye (Secale cereale) is an important crop with multiple uses and a valuable genetic resource for wheat breeding. However, due to its complex genome and outcrossing nature, the origin of cultivated rye remains elusive. The geneticist N.I. Vavilov proposed that cultivated rye had been domesticated from weedy rye, rather than directly from wild species like other crops. Unraveling the domestication history of rye will extend our understanding of crop evolution and upend our inherent understanding of agricultural weeds. To this end, in this study we generated the 8.5 Tb of whole-genome resequencing data from 116 worldwide accessions of wild, weedy, and cultivated rye, and demonstrated that cultivated rye was domesticated directly from weedy relatives with a similar but enhanced genomic selection by humans. We found that a repertoire of genes that experienced artificial selection is associated with important agronomic traits, including shattering, grain yield, and disease resistance. Furthermore, we identified a composite introgression in cultivated rye from the wild perennial Secale strictum and detected a 2-Mb introgressed fragment containing a candidate ammonium transporter gene with potential effect on the grain yield and plant growth of rye. Taken together, our findings unravel the domestication history of cultivated rye, suggest that interspecific introgression serves as one of the likely causes of obscure species taxonomy of the genus Secale , and provide an important resource for future rye and wheat breeding. This study provides insight into genetic underpinning of the domestication of rye, a secondary domesticate (Vavilovian hypothesis) directly from weedy rye, based on genome resequencing data of 116 Secale accessions. A repertoire of domestication genes and a 2-Mb introgressed fragment from Secale strictum associated with important traits were identified, providing an important resource for future rye and wheat breeding. [ABSTRACT FROM AUTHOR]

Our focus is on the online linear packing-covering problem (OLPCP). Within this domain, we present an algorithm that attains near-optimal performance based on generalized Chernoff bounds for general random variables, assuming inputs are received in a uniformly random order and under almost stringent conditions. Through VCG protocols, we are able to unveil the inaugural truthful near-optimal mechanism for OLPCP, all within the confines of nearly tight conditions. [ABSTRACT FROM AUTHOR]

• Aggregation-induced photothermal effect has been achieved by GNSCs-thiolates. • Cysteamine can trigger the efficient release of silver alloy species from GNSCs. • The silver release and photothermal effect can synergistically kill MDR bacteria. Gold silver nanocages (GSNCs) have been applied as an excellent nano-cargo for drug delivery and near infrared (NIR) photothermal therapy due to their tunable optical properties and biocompatibility. However, a dilemma is that GSNCs with NIR adsorption normally have a highly-hollow silver core and thick gold coating, which largely mitigates the antibacterial activity because of the limited use of contained silver species. Here we have proposed an alternative strategy on basis of the aggregation induced photothermal (AIP) effect by the combination of high silver-loading GSNCs and thiolates. Interestingly, a typical thiolate, cysteamine, was found to rapidly induce the release of ultrasmall silver alloy species from GSNCs, with at least 4 fold amount compared with that by other thiolates. The booming silver release from GSNCs and NIR photothermal effect synergistically allow the removal of the biofilm secreted by multidrug resistant (MDR) bacteria in vitro and the eradication of MDR S. aureus in infection wound of mice. This strategy may provide a promising method for effective treatment of intractable MDR bacterial infection. [ABSTRACT FROM AUTHOR]

Self-healing coatings have shown promise in controlling the degradation of scaffolds and addressing coating detachment issues. However, developing a self-healing coating for magnesium (Mg) possessing multiple biological functions in infectious environments remains a significant challenge. In this study, a self-healing coating was developed for magnesium scaffolds using oxidized dextran (OD), 3-aminopropyltriethoxysilane (APTES), and nano-hydroxyapatite (nHA) doped micro-arc oxidation (MHA), named OD-MHA/Mg. The results demonstrated that the OD-MHA coating effectively addresses coating detachment issues and controls the degradation of Mg in an infectious environment through self-healing mechanisms. Furthermore, the OD-MHA/Mg scaffold exhibits antibacterial, antioxidant, and anti-apoptotic properties, it also promotes bone repair by upregulating the expression of osteogenesis genes and proteins. The findings of this study indicate that the OD-MHA coated Mg scaffold possessing multiple biological functions presents a promising approach for addressing infectious bone defects. Additionally, the study showcases the potential of polysaccharides with multiple biological functions in facilitating tissue healing even in challenging environments. [Display omitted] [ABSTRACT FROM AUTHOR]

A high sensitive and selective hydrogen peroxide (H2O2) biosensor was fabricated on the basis of reduced hemoglobin (Hb) and single-walled carbon nanotubes (SWCNTs) for detecting the release of H2O2 from living HepG2 cancer cells in the process of the in situ biosynthesis of ZnO quantum. The modification of carbon fiber microelectrode (CFME) was carried out by physical adsorption. By the scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), the dense cover of surface and successful immobilization were characterized. Electrochemical investigation demonstrates that the as-prepared modified microelectrode showed a quasi-reversible process toward the reduction of H2O2, which exhibited a linear range from 0.51 to 10.6 μM, with a limit of detection of 0.23 μM. This microelectrode biosensor was applied for the quantification of the change of H2O2 concentration released from HepG2 cells through the in situ biosynthesis of ZnO quantum dots, which was further confirmed by the fluorescence staining. [ABSTRACT FROM AUTHOR]

A high-sensitive nonenzymatic hydrogen peroxide (H 2 O 2 ) biosensor based on cuprous iodide and graphene (CuI/Gr) composites has been explored for the detection of H 2 O 2 released by living cells and monitoring the oxidative stress of cells under excellular stimulation. The biosensor properties were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), amperometric i-t curve, and the redox-competition mode of scanning electrochemical microscopy (SECM). Our observations demonstrate that the CuI/Gr nanocomposites modified glassy carbon electrode (GCE) exhibits excellent catalytic activity for H 2 O 2 with relatively low detection limit and a wide linear range from 0.5 μM to 3 mM. Moreover, the redox-competition mode of SECM imaging study further illustrates the improved electrochemical catalytic capability for H 2 O 2 reduction with CuI/Gr nanocomposites deposited on graphite electrode. Hence, the as-prepared nonenzymatic H 2 O 2 biosensor could be used to detect H 2 O 2 release from different kinds of living cells under stimulation while eliminating the interference of ascorbic acid. [ABSTRACT FROM AUTHOR]

Inspired by humpback whale belly grooves which may impart stability, we hypothesized that adding grooves to the head of submarine-launched vehicle (SLV) would weaken the effect of wave force. An experimental instrument was built to test a prototype submarine-launched vehicle (SLVP; no grooves) and 9 bionic submarine-launched vehicles (SLVBs) with different grooves on the head. The deflection angles of the SLVP and SLVBs were measured as they crossed the water-air interface in wavy conditions. The experimental results showed that the SLVBs had smaller deflection angles than the SLVP, which supported the initial hypothesis. The angular deflection of the SLVP and SLVBs in wavy conditions was then analyzed using a simulation. The simulated and experimental results agreed, confirming the validity of the simulated models. By measuring the torque experienced at the center of gravity of the SLVs and the flow field distributions near the heads of the SLVs in the simulation, the mechanism behind the differences in angular deflection of the SLVs with and without grooves was revealed. • Inspired by humpback whale, we hypothesized that adding grooves to the head of SLV would weaken the impact of waves. • An experimental instrument was built to test a SLVP (no grooves) and 9 SLVBs with different grooves on the head. • The experimental and simulated data supported the correctness of the hypothesis proposed in this paper. • The reason behind the differences in angular deflection of the SLVs with and without grooves was revealed. [ABSTRACT FROM AUTHOR]

Scheme. Antibacterial strategies of Ag-based alloys. (A). Different Ag+ releasing behaviors for silver-noble metals alloys. (B). Multiple antibacterial approaches silver-noble metals alloys. [Display omitted] • Controllable Ag+ release from Ag nanoalloys may enhance antibacterial efficiency. • Different etching agents are compared for Ag+ release from Au-Ag nanoalloys. • Synergistic antibacterial effect by photothermal therapy and Ag+ release. • Ag-Pt(Pd) nanoalloys may kill bacteria by production of reactive oxygen species. Currently, indiscriminate use of traditional antibiotics drives the rapid evolution of multidrug-resistant pathogenic bacteria. Silver has been regarded as antimicrobial agent since ancient times, while silver nanostructures can treat bacteria through multiple interaction mechanisms, such as enhanced targetability, augmented drug loading efficiency and tunable physiochemical property. Generally, nano-silver with small sizes can eliminate pathogenic bacteria more efficiently, while it tends to aggregate, causing instability. After the formation of alloys with other noble metal elements such as gold, platinum, palladium, the stability of these nanomaterials can be significantly enhanced, with antibacterial activity maintained. Therefore, in this review, we focus on the roles of silver in Ag-based alloy nanostructure for antibacterial activity, according to the following mechanisms: the release of Ag+ ions to directly disturb the bacterial metabolism, the assistance to modulate surface plasmonic resonance adsorption of Ag-alloys to realize near infrared phototherapy, and the combination with Pt or Pd to the production of catalyze reactive oxygen species under bacterial microenvironment. Based on these understandings, we will summarize some common antibacterial disciplines for Ag-based nanoalloys, which may guide the further investigation for efficient antibacterial applications. [ABSTRACT FROM AUTHOR]

Oxidative stress plays an important role in the pathogenesis of myocardial infarction (MI). Schisandra chinensis bee pollen extract (SCBPE) possesses powerful antioxidant capacity. This study aimed to further explore the antioxidative and cardioprotective effects of SCBPE on acute MI induced by isoprenaline (ISO) in rats. The rats were intragastrically administrated with SCBPE (600, 1200, or 1800 mg/kg/day) and Compound Danshen dropping pills (270 mg/kg/day) for 30 days, then subcutaneously injected with ISO (65 mg/kg/day) on the 29th and 30th day. Compared with the model group, pretreatment with middle and high doses of SCBPE significantly reduced serum aspartate transaminase, lactate dehydrogenase, and creatine kinase activities and increased myocardial superoxide dismutase, glutathione peroxidase, and catalase activities. The histopathologic aspects showed that pathological heart change was found in the model group and reduced to varying degrees in the SCBPE groups. Moreover, the protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), and Bcl2 in the heart increased in the SCBPE groups, while that of Bax decreased compared to the model group. Besides this, uridine was isolated from S. chinensis bee pollen for the first time. This study could provide a scientific basis for using Schisandra chinensis bee pollen as a functional food for the prevention of MI. [ABSTRACT FROM AUTHOR]

The authors would like to call the reader’s attention to the fact that unfortunately Alberto Pasquarelli’s and Kay-Eberhard Gottschalk’s affiliations were wrong in the original publication. [ABSTRACT FROM AUTHOR]