Rational design of Near-Infrared fluorescent probe for monitoring HNO in plants.

Nitroxyl (HNO), a reactive nitrogen species (RNS), is essential for plant growth. However, the action of HNO in plants has been difficult to understand due to the lack of highly sensitive and real-time in-situ monitoring tools. Herein, we presented a near-infrared fluorescent probe, DCI-HNO, based on dicyanoisophorone fluorophore, for real-time mapping HNO in plants. The introduction of a phosphine moiety as a specific HNO recognition unit can inhibit the intramolecular charge transfer (ICT) of probe DCI-HNO. However, in the presence of HNO, the ICT process occurred, leading to the emission at 665 nm. Probe DCI-HNO exhibited high sensitivity (97 nM), rapid response time (8 min), large Stokes shift (135 nm) for detection of HNO in plants. The novel developed probe has successfully imaged endogenous HNO produced during NO/H2S cross-talk in plant tissues. Additionally, the up-regulated in HNO levels during tobacco aging and in response to stress has been confirmed. Therefore, probe DCI-HNO has provided a reliable method for monitoring the NO/H2S cross-talk and revealing the role of HNO in plants.

Analysis of carbon emission equity degrees based on regional heterogeneity in China.

Carbon emission reduction is an environmental and development issue that needs to consider various factors, such as the economy and people's livelihood. Supporting the achievement of emission reduction targets has become an important planning goal for provincial governments; however, there are differences in provincial industrial structure and economic development, which cannot be ignored in goal setting. This study measures the equity degrees of carbon emissions based on economic output by using provincial panel data from 2000 to 2019 and evaluates the spatial distribution characteristics of the carbon emission inequity index (CII). Then, analysis of the influencing factors to CII is employed by spatial econometric methods. Furthermore, multi-index panel data factor analysis and cluster analysis are used to divide regions. The empirical results show that nearly half of the provinces have the problem of carbon emissions inequity with significant spatial correlation. For local development, economic growth and population expansion will significantly improve the equity degrees of carbon emissions. In contrast, the growth of urbanization level, the percentage of secondary industry, and increased energy intensity will significantly improve the equity degrees of carbon emissions in neighboring regions. Policymakers should consider the factors influencing CII and formulate emission reduction plans according to regional characteristics.

CENPF promotes the proliferation of renal cell carcinoma in vitro.

Background: Metastasis and drug resistance are the main causes of renal cell carcinoma (RCC) mortality. Currently, there are still a limited number of targeted therapies against advanced RCC. It is critical to develop new effective clinical biomarkers and drug targets in RCC. Several studies have shown that centromere protein F (CENPF), a microtubule binding protein, promotes cancer progression in various types of cancer. The purpose of this study was to explore the role of CENPF in RCC. Methods: Peripheral blood and corresponding tissue samples of 23 RCC patients and 23 normal physical examination patients who were treated in our hospital from 2018 to 2020 were collected, and CENPF expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunohistochemical (IHC) methods. The expression of CENPF was downregulated by small interfering RNA (siRNA) transfection, and the proliferation of the corresponding RCC cells and the corresponding cell cycle were detected. Results: According to The Cancer Genome Atlas (TCGA) data analysis, CENPF is highly expressed in RCC, and its expression level is significantly related to the overall survival (OS) and recurrence-free survival (RFS) of RCC. In addition, high expression of CENPF was found in the tissues of RCC patients in our hospital. Knockdown of CENPF significantly reduced the proliferation of RCC cells in vitro, and knockdown of CENPF regulated the cell cycle by inhibiting the expression of cyclins such as CDK4, CDK6, and CyclinD1. Conclusions: CENPF can be used as an independent prognostic factor of RCC and regulate the proliferation ability and cell cycle of RCC cells. CENPF is a potential oncogene and prognostic marker in RCC.

Modular-assembled laser system for a long-baseline atom interferometer.

The Zhaoshan long-baseline Atom Interferometer Gravitation Antenna (ZAIGA) is a new, to the best of our knowledge, type of large-scale atom interferometer facility under construction for the study of gravitation and related problems. To meet the different requirements of the laser system for the atom interferometer using various atoms (including 85Rb, 87Rb, 87Sr, and 88Sr), we design and implement a modular assembled laser system. By dividing the laser system into different basic units according to their functions and modularizing each unit, the laser system is made highly scalable while being compact and stable. Its intensity stability is better than 0.1% in 102s and 0.5% in 104s. We test the performance of the laser system with two experimental systems, i.e., an 85Rb-87Rb dual-species ultracold atom source and an 85Rb atom interferometer. The 85Rb-87Rb dual-species magneto-optical trap and the 85Rb atom interference fringes are realized by using this laser system, indicating that its technical performance can meet the major experimental requirements.

An actively compensated 8 nT-level magnetic shielding system for 10-m atom interferometer.

We design and develop a high-performance magnetic shielding system for a long baseline fountain-type atom interferometer. The shielding system is achieved by a combination of passive shielding using permalloy and active compensation with coils. An 11.4 m-long three-layer cylindrical shield is completed by the process of welding, local annealing, and entire annealing. The active compensations compress the residual magnetic field to 8.0 nT max-to-min and the corresponding gradient below 30 nT/m over 10 m along the axial direction in which external compensation, internal compensation, and constant magnetic field (C-field) compensation reduce the inhomogeneities to 25.0, 12.6, and 1.7 nT (standard deviation) sequentially. We estimate that this system could reduce the systematic error of the quadratic Zeeman shift to the 10-13 level for the weak equivalence principle test with a simultaneous 85Rb-87Rb dual-species atom interferometer.

GaOx@GaN Nanowire Arrays on Flexible Graphite Paper with Tunable Persistent Photoconductivity.

Flexible optoelectronic synaptic devices that functionally imitate the neural behavior with tunable optoelectronic characteristics are crucial to the development of advanced bioinspired neural networks. In this work, amorphous oxide-decorated GaN nanowire arrays (GaOx@GaN NWAs) are prepared on flexible graphite paper. A GaOx@GaN NWA-based flexible device has tunable persistent photoconductivity (PPC) and shows a conversible fast/slow decay process (SDP). Photoconductivity can be modulated by single or double light pulses with different illumination powers and biases. PPC gives rise to the high-performance SDP such as a long decay time of 2.3 × 105 s. The modulation mechanism is proposed and discussed. Our results reveal an innovative and efficient strategy to produce decorated NWAs on a flexible substrate with tunable optoelectronic properties and exhibit potential for flexible neuromorphic system applications.

All acousto-optic modulator laser system for a 12 m fountain-type dual-species atom interferometer.

We design and implement a laser system for 85Rb and 87Rb dual-species atom interferometers based on acousto-optic frequency shift and tapered amplifier laser technologies. We use eight-pass acousto-optic modulators to generate repumping lasers for 85Rb and 87Rb atoms. The maximum frequency shift of the laser is 2.8 GHz, and the diffraction efficiency is higher than 20%. We use high-frequency acousto-optic modulators to generate the Raman lasers. This laser system uses only two seed lasers to provide the various frequencies required by 85Rb and 87Rb dual-species atom interferometers, which greatly improves laser usage. The laser system is applied in the equivalence principle test experiment using an 85Rb and 87Rb dual-species atom interferometer. The signal of atoms launched to 12 meters is successfully observed, and the resolution of gravity differential measurement is improved from 8×10-9 g to 1×10-10g.

Case Report: A Unique Case of Pediatric Central Nervous System Embryonal Tumor Harboring the CIC-LEUTX Fusion, Germline NBN Variant and Somatic TSC2 Mutation: Expanding the Spectrum of CIC-Rearranged Neoplasia.

Central nervous system (CNS) embryonal tumors (WHO grade IV) are a heterogeneous group of rare, poorly differentiated neuroepithelial malignant neoplasms that commonly occur in children, and they have a poor prognosis. The 2016 WHO (World Health Organization) classification of CNS tumors created a major shift in paradigm of the classification of embryonal tumors. However, some cases were still difficult to classify. Further integrative genomic analysis is needed to improve the precise classification, diagnosis and treatment of CNS embryonal tumors. Herein, we firstly report a case of CNS embryonal tumor harboring the pathogenic CIC-LEUTX gene fusion. A 2-year-old male infant presented with a solid cystic mass in the left temporal lobe-basal ganglia and left parietal lobe (maximum diameter, 75 mm) and underwent gross tumor resection. The tumor was classified as a poorly differentiated embryonal neoplasm of neuroectodermal origin that lacked specific features and rosettes. By immunohistochemistry, the tumor cells were strongly positive for synaptophysin, and the Ki67 proliferation index was high (>50%). FISH (Fluorescence in situ hybridization) results indicated no change in the copy number at the 19q13.42 C19MC locus. Next generation sequencing showed a CIC-LEUTX gene fusion, a somatic TSC2 c.G2714A mutation, and a heterozygous germline NBN c.C127T mutation. One month after surgery, there was recurrence of the intracranial tumor (maximum diameter, 55 mm) as well as spinal cord implantation metastasis. The patient received chemotherapy (CTX+CBP+VCR/DDP+VP-16), radiotherapy, and a drug targeting the TSC2 gene (everolimus). At the time of this writing, the patient is alive without evidence of disease for 11 months. This is the first report of the CIC-LEUTX gene fusion in a case of CNS embryonal tumor.

Strain-enhanced power conversion efficiency of a BP/SnSe van der Waals heterostructure.

A promising BP/SnSe van der Waals (vdW) photovoltaic heterostructure was designed and investigated by first-principles calculations. The BP/SnSe vdW heterostructure showed inhibition of photogenerated carrier recombination as well as broad and high optical absorption intensity spanning the visible to deep ultraviolet regions reaching the order of 105 cm-1. The carrier mobility of the BP/SnSe vdW heterostructure exhibited anisotropic characteristics reaching approximately 103 cm2 V-1 s-1, with an intrinsic power conversion efficiency (PCE) of 11.96%. Our results show that the PCE can be increased to 17.24% when the conduction band offset between BP and SnSe is reduced by strain engineering. The distinctive and favorable properties suggest that the BP/SnSe vdW heterostructure has great potential for use in photovoltaic devices.

Laser frequency shift up to 5 GHz with a high-efficiency 12-pass 350-MHz acousto-optic modulator.

We demonstrate a novel laser frequency shift scheme using a 12-pass 350-MHz acousto-optic modulator (AOM). This AOM system shows better performance compared to ordinary acousto-optic modulation schemes. The frequency of the incident laser beam is shifted by 4.2 GHz with the total diffraction efficiency as high as 11%, and the maximum frequency shift is 5 GHz. Combining the ±1st order diffraction, laser signals with up to 10 GHz frequency difference can be obtained, which fulfill most frequency shift requirements of laser cooling and coherent manipulation experiments with alkali metal atoms.

Effects of sulfated, phosphorylated and carboxymethylated modifications on the antioxidant activities in-vitro of polysaccharides sequentially extracted from Amana edulis.

In this study, four sequentially extracted polysaccharides (AEPs) from Amana edulis were modified by sulphation, phosphorylation, and carboxylation modifications (S-AEPs, P-AEPs, C-AEPs), and compared for their anti-oxidant activities. After modification, sugar and protein contents were decreased and uronic acid content was increased in comparison to native AEPs. UV absorption showed similar maximum absorption peaks of modified derivatives which indicated their homogeneous nature. FTIR spectra confirmed the conversion of hydroxyl groups to OS, COO, and POH bonds, respectively. The phosphorylated derivatives (P-AEPs) displayed the highest DPPH, hydroxyl radical, and ferrous ions radical scavenging abilities. Sulfated polysaccharides (S-AEPs) were observed with high reducing ability. The C-AEPs maintained the stable antioxidant properties after carboxylation modification. Our results indicated that the chemical modification of different polysaccharide components has significantly affected their antioxidant potential for their use in food industry and human health.

The rheological properties and emulsifying behavior of polysaccharides sequentially extracted from Amana edulis.

The rheological properties and emulsifying behavior of four polysaccharides (HBSS, CHSS, DASS, and CASS) sequentially extracted from Amana edulis (AEPs) were investigated under various concentrations, temperatures, pH levels, and ionic strengths. The apparent viscosity of the four AEPs solutions at 1% (w/w) concentration were found to be CHSS > DASS > HBSS > CASS. When the AEPs were heated to 100 οC, they showed lower colloidal viscosity, whereas after refrigeration and chilling, higher apparent viscosities were observed. The apparent viscosity of four AEPs at pH 10 or pH 4 was lower than that at pH 7. The apparent viscosity increased at a lower sodium ion concentration and then declined with an increase in ion concentration. The storage modulus (G') and loss modulus (G″) increased with an increase in oscillation frequency. The emulsifying activity and stability were enhanced as the concentration of the four AEPs increased. The emulsifying activity and stability of the AEPs were steady within the pH range of 2-10 and NaCl concentration range of 0-0.4 mol/L. Our results implied that these polysaccharides can be utilized as a novel hydrocolloid source for natural thickeners in the food industry.

Stability and Repeatability of a Karst-like Hierarchical Porous Silicon Oxide-Based Memristor.

A memristor architecture based on porous oxide materials has the potential to be used in artificial synaptic devices. Herein, we present a memristor system employing a karst-like hierarchically porous (KLHP) silicon oxide structure with good stability and repeatability. The KLHP structure prepared by an electrochemical process and thermal oxidation exhibits high ON-OFF ratios up to 105 during the endurance test, and the data can be maintained for 105 s at a small read voltage 0.1 V. The mechanism of lithium ion migration in the porous silicon oxide structure has been discussed by a simulated model. The porous silicon oxide-based memristor is very promising because of the enhanced performance as well as easily accessed neuromorphic computing.

Physicochemical and antioxidant potential of polysaccharides sequentially extracted from Amana edulis.

Amana edulis polysaccharides (AEPs) specifically HBSS, CHSS, DASS, and CASS were sequentially extracted with four different solvents. The present study characterized the AEPs with particular focus on their physicochemical and anti-oxidant based functional properties. Initially, monosaccharide analysis revealed arabinose (31.7%, 32.5%, 36.5%) as the main sugar in HBSS, CHSS, and DASS whereas, galactose (31.4%) in CASS besides their respective molecular weights of 6.29 × 102, 1.5 × 102, 8.1 × 102, and 2.6 × 103 kD. HBSS showed the maximum solubility, while, CASS was observed for higher foam capacity and foam stability. Among all the fractions, DASS was observed with higher thermal stability. HBSS showed the highest ABTS+ scavenging activity. HBSS and CASS had higher DPPH and OH- scavenging activities. DASS depicted the highest chelation and reducing ability. To summarize, these polysaccharides fractions may be further utilized for their enormous prospective in functional foods preparation.

A rolling circle amplification-assisted DNA walker triggered by multiple DNAzyme cores for highly sensitive electrochemical biosensing.

DNA walkers from monopodial to multipedal types have usually one cleavage site to power the walking system along with the track. Herein, a multipedal DNA walker (m-DNA walker) with multiple DNAzyme cores was constructed with the assistance of rolling circle amplification (RCA) for highly sensitive electrochemical biosensing. Firstly, a three-component DNA complex as a swing strand was prepared by integrating a padlock, an RCA primer and a block DNA as a recognition element in the DNA walker system. After ferrocene-labeled track DNA (trDNA) and capture DNA were fixed on a gold electrode, the three-component DNA complex was imported onto the electrode as a swing arm to form a m-DNA walker. In the presence of target DNA and a RCA kit, the block was displaced from the complex and RCA was initiated to form multiple DNAzyme strands. Upon hybridization with trDNA, the m-DNA walker was motivated by the cleavage of multiple DNAzyme cores in the presence of manganese ions to free signal molecules. Under the optimal circumstances, the electrochemical m-DNA walker showed a linear range from 1.0 fM to 1.0 nM with a detection limit of 0.28 fM. Moreover, the m-DNA walker demonstrated a rapid cleavage rate and a low ratio of the swing strand to the track, which is more excellent than a single foot walker and a bipedal DNA walker. The practicality of the proposed strategy was also confirmed by detecting target DNA in 10% human serum, showing promising applications in clinical diagnosis.

Binding-induced DNA walker for signal amplification in highly selective electrochemical detection of protein.

A binding-induced DNA walker-assisted signal amplification was developed for highly selective electrochemical detection of protein. Firstly, the track of DNA walker was constructed by self-assembly of the high density ferrocene (Fc)-labeled anchor DNA and aptamer 1 on the gold electrode surface. Sequentially, a long swing-arm chain containing aptamer 2 and walking strand DNA was introduced onto gold electrode through aptamers-target specific recognition, and thus initiated walker strand sequences to hybridize with anchor DNA. Then, the DNA walker was activated by the stepwise cleavage of the hybridized anchor DNA by nicking endonuclease to release multiple Fc molecules for signal amplification. Taking thrombin as the model target, the Fc-generated electrochemical signal decreased linearly with logarithm value of thrombin concentration ranging from 10pM to 100nM with a detection limit of 2.5pM under the optimal conditions. By integrating the specific recognition of aptamers to target with the enzymatic cleavage of nicking endonuclease, the aptasensor showed the high selectivity. The binding-induced DNA walker provides a promising strategy for signal amplification in electrochemical biosensor, and has the extensive applications in sensitive and selective detection of the various targets.