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Abstract The post-processing of quantum key distribution mainly includes error correction and privacy amplification. The error correction algorithms and privacy amplification methods used in the existing quantum key distribution are completely unrelated. Based on the principle of correspondence between error-correcting codes and hash function families, we proposed the idea of time-division multiplexing for error correction and privacy amplification for the first time. That is to say, through the common error correction algorithms and their corresponding hash function families or the common hash function families and their corresponding error-correcting codes, error correction and privacy amplification can be realized by time-division multiplexing with the same set of devices. In addition, we tested the idea from the perspective of error correction and privacy amplification, respectively. The analysis results show that the existing error correction algorithms and their corresponding hash function families or the common privacy amplification methods and their corresponding error-correcting codes cannot realize time-division multiplexing for error correction and privacy amplification temporarily. However, according to the principle of correspondence between error-correcting codes and hash function families, the idea of time-division multiplexing is possible. Moreover, the research on time-division multiplexing for error correction and privacy amplification has some practical significance. Once the idea of time-division multiplexing is realized, it will further reduce the calculation and storage cost of the post-processing process, reduce the deployment cost of quantum key distribution, and help to remote the practical engineering of quantum key distribution.

Martentoxin (MarTX), a 37-residue peptide purified from the venom of East-Asian scorpion (Buthus martensi Karsch), was capable of blocking large-conductance Ca2+-activated K+ (BK) channels. Here, we report an effective expression and purification approach for this toxin. The cDNA encoding martentoxin was expressed by the prokaryotic expression system pGEX-4T-3 which was added an enterokinase cleavage site by PCR. The fusion protein (GST-rMarTX) was digested by enterokinase to release hetero-expressed toxin and further purified via reverse-phase HPLC. The molecular weight of the hetero-expressed rMarTX was 4059.06 Da, which is identical to that of the natural peptide isolated from scorpion venom. Functional characterization through whole-cell patch clamp showed that rMarTX selectively and potently inhibited the currents of neuronal BK channels (α + β4) (IC50 = 186 nM), partly inhibited mKv1.3, but hardly having any significant effect on hKv4.2 and hKv3.1a even at 10 μM. Successful expression of martentoxin lays basis for further studies of structure-function relationship underlying martentoxin or other potassium-channel specific blockers.

Abstract Background Whether endobiliary radiofrequency ablation (EB-RFA) changes the standard role of stent placement in treating unresectable malignant biliary obstruction (MBO) remains unclear. The aim of this study is to compare percutaneous EB-RFA and metal stent placement (RFA-Stent) with metal stent placement alone (Stent) in treating unresectable MBO using a propensity score matching (PSM) analysis. Methods From June 2013 to June 2018, clinical data from 163 patients with malignant biliary obstruction who underwent percutaneous RFA-Stent or stenting alone were retrospectively analyzed using a nearest-neighbor algorithm to one-to-one PSM analysis to compare primary and secondary stent patency (PSP, SSP), overall survival (OS) and complications between the two groups. Results Before matching, for whole patients, RFA-Stent resulted in longer median PSP (8.0 vs. 5.1 months, P = 0.003), SSP (9.8 vs. 5.1 months, P

Based on sequence variation in the N-terminus of the UL55 gene, which encodes glycoprotein B (gB), human cytomegalovirus (CMV) can be classified into four gBn genotypes. We assessed the distribution of CMV gBn genotypes and the correlation between CMV gBn DNA (detected by real-time PCR) and CMV-positive pp65 cells (identified by immunohistochemical staining) in a cohort of hematopoietic stem cell transplant patients. The distribution of gB genotypes was as follows: gBn1, 60% of patients; gBn2, 13.3%; mixed gBn1 and gBn3 infection, 26.7%; and gBn4 and other mixed infections, 0%. CMV gBn1 was the most common genotype. The detected level of CMV gB DNA correlated well with the number of CMV-positive pp65 cells detected by immunostaining (r = 0.585).

The detection of volatile amines is necessary due to the serious toxicity hazards they pose to human skin, respiratory systems, and nervous systems. However, traditional amines detection methods require bulky equipment, high costs, and complex measurements. Herein, we report a new simple, rapid, convenient, and visual method for the detection of volatile amines based on the gas–solid reactions of tetrachloro-p-benzoquinone (TCBQ) and volatile amines. The gas–solid reactions of TCBQ with a variety of volatile amines showed a visually distinct color in a time-dependent manner. Moreover, TCBQ can be easily fabricated into simple and flexible rapid test strips for detecting and distinguishing n-propylamine from other volatile amines, including ethylamine, n-butyamine, n-pentamine, n-butyamine and dimethylamine, in less than 3 s without any equipment assistance.

The lead-free ceramics ([Formula: see text])(0.94[Formula: see text][Formula: see text][Formula: see text]TiO3-0.06BiAlO3)-[Formula: see text]AgNbO3 (denoted as BNBTA-[Formula: see text]AN) were synthesized via a solid-state sintering method. The effect of AgNbO3 doping amount on dielectric properties of the ceramics was studied systematically. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectroscope were used to detect the structure of the ceramics. Temperature-dependent dielectric spectra, frequency-dependent dielectric constant and alternating current (ac) electric conductance at various temperatures were measured. The doping of AgNbO3 greatly reduces dielectric constant around Curie temperature and thus enhances the temperature stability of the dielectric constant. The ceramic BNBTA-0.03AN exhibits excellent temperature-stable dielectric properties with temperature coefficient of capacitance (TCC) [Formula: see text]15% between 55∘C and 418∘C with temperature window 363∘C and small changes of dielectric constant and dielectric loss from 100 Hz to 1 MHz at different temperatures. The obtained ceramics are expected to be used in high-temperature capacitors due to its excellent temperature stability.

In recent years, energetic molecular perovskites, which serve as an energetic material design platform, have shown potential for designing primary and secondary explosives. To explore their potential in gunpowder and pyrotechnics, this study constructed a new nitrate-bridged molecular perovskite, (H2dabco)[K(NO3)3] (DAN-2, H2dabco2+ ​= ​1,4-diazabicyclo-[2.2.2.]octane-1,4-diium), based on potassium nitrate—a major component of black powder. The single-crystal structure analysis indicated that DAN-2 possesses a cubic perovskite structure in the space group Pm 3¯ m. Theoretical calculations revealed that DAN-2 has an energy level slightly higher than TNT and much higher than black powder. Adding DAN-2 into a typical propellant formulation can increase the impetus while significantly lowering the flame temperature. Moreover, DAN-2 has a lower sensitivity (IS ​= ​29 ​J, FS > 360 ​N) than TNT (IS ​= ​15 ​J, FS ​= ​360 ​N). It is worth mentioning that DAN-2 can avoid the environmental concern of sulfide-induced acid rain since it does not bear any sulfur. Therefore, DAN-2 can be considered a new single explosive and a modern edition of black powder obtained via mixing oxidative KNO3 and a reductive organic fuel at the molecular scale. Furthermore, it displays promising potential in the field of gunpowder and pyrotechnics.

Research on the structural responses to thermal stimuli for crystalline energetic materials is crucial to their practical applications. DAP-4 is a metal-free molecular perovskite high-energetic material attracting increasing attentions on its application potential as heat-resistant explosive. In order to reveal its structural responses to thermal stimuli, herein we investigated the structural phase transitions and thermal expansion of DAP-4 by DSC, single-crystal X-ray diffraction, and variable-temperature capillary powder X-ray diffraction. The results show that DAP-4 undergoes two-step reversible phase transitions at 300.4/298.9 K and 548.4/547.7 K, respectively, which are caused by two-step order-disorder transition of the molecular components during a heating/cooling cycle. The axial and the volumetric expansion coefficients of DAP-4 are estimated based on the temperature-dependent cell parameters obtained by Pawley refinement in a large temperature range of 173–353 K, and they are close to those estimated for β-HMX. Notably, although a volume change of 0.77% occur in the near-room-temperature phase transition, all the crystalline phases of DAP-4 possess cubic structures with isotropic expansibility, rather than the commonly-observed anisotropic one in the most of known energetic crystals, which may be propitious to reduce the adverse effect of its volume change on the formulation design.

Background: Infantile hemangiomas (IH) and venous malformations (VM) are the most common types of vascular abnormalities that seriously affect the health of children. Although there is evidence that these two diseases share some common genetic changes, the underlying mechanisms need to be further studied.Methods: The microarray datasets of IH (GSE127487) and VM (GSE7190) were downloaded from GEO database. Extensive bioinformatics methods were used to investigate the common differentially expressed genes (DEGs) of IH and VM, and to estimate their Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Trough the constructing of protein-protein interaction (PPI) network, gene models and hub genes were obtained by using Cytoscape and STRING. Finally, we analyzed the co-expression and the TF-mRNA-microRNA regulatory network of hub genes.Results: A total of 144 common DEGs were identified between IH and VM. Functional analysis indicated their important role in cell growth, regulation of vasculature development and regulation of angiogenesis. Five hub genes (CTNNB1, IL6, CD34, IGF2, MAPK11) and two microRNA (has-miR-141-3p, has-miR-150-5p) were significantly differentially expressed between IH and normal control (p < 0.05).Conclusion: In conclusion, our study investigated the common DEGs and molecular mechanism in IH and VM. Identified hub genes and signaling pathways can regulate both diseases simultaneously. This study provides insight into the crosstalk of IH and VM and obtains several biomarkers relevant to the diagnosis and pathophysiology of vascular abnormalities.

Benzene, cyclohexane, and cyclohexene are essential raw materials in the petrochemical industry. Their separation and purification rely on traditional distillation processes that consume a large amount of energy due to their close boiling points. Here, we describe a new microporous metal azolate framework for mild adsorptive and kinetic separation of the three hexacyclic hydrocarbons. This metal azolate framework exhibits ultrafast benzene adsorption in a short saturation time within seconds and ultrafast kinetic adsorptive separation of benzene/cyclohexane and benzene/cyclohexene. Investigation into the adsorption kinetics of benzene, cyclohexane and cyclohexene reveals a two-step adsorption process, including steps of intraparticle diffusion and surface adsorption, respectively. Also, by adjusting the sample particle size, the adsorption behaviour can be significantly controlled. The large-particle sample achieves a high selectivity for benzene/cyclohexene (94.3) and an inverse selectivity for cyclohexane/cyclohexene, being opposite to the small-particle sample. This highlights the feasibility of controlling adsorption selectivity by manipulating the kinetic steps in porous materials. [ABSTRACT FROM AUTHOR]

Molecular perovskite energetic crystals, as an emerging family of promising practicable energetic materials, have attracted increasing attentions in the past few years. Different from the mainstream strategies focusing on the intra-molecular designs and modifications on fused-ring energetic molecules/ions, molecular perovskites rely on the self-assembly of diverse molecular components into specified ternary crystal structures, hence generally could be prepared via an easy scale-up process at a low cost. As a kind of ternary salts, they have some unique advantages on the energetic-material designs in terms of optimizing oxygen balance, increasing pack efficiency (and crystal density), and decreasing hygroscopicity, hence could achieve improved detonation performances meanwhile overcome some technical weaknesses of traditional energetic binary salts. In this review, we summarize the current findings and understandings on molecular perovskite energetic crystals, and provide an outlook for the new opportunities brought by this new and promising material family towards advanced multi-component energetic crystals.

Complicated vomiting and hypercalcemia are clinically rare in patients with hyperthyroidism. We describe a case of a woman whose main symptoms were palpitations, sweating, and vomiting. She was diagnosed with Graves’ disease by an analysis of thyroid function, thyroid-related antibodies, and color Doppler ultrasound. Biochemical tests showed that her serum calcium levels were greatly elevated. Her symptoms were relieved following the administration of antithyroid drugs, propranolol for heart rate control, fluid replacement, diuresis and calcium reduction, antiemesis, and liver protection. This case suggests that the thyroid function should be screened when hypercalcemia is seen in the clinic.

Abstract The aphid Schlechtendalia chinensis is an economically important insect that can induce horned galls, which are valuable for the medicinal and chemical industries. Up to now, more than twenty aphid genomes have been reported. Most of the sequenced genomes are derived from free‐living aphids. Here, we generated a high‐quality genome assembly from a galling aphid. The final genome assembly is 271.52 Mb, representing one of the smallest sequenced genomes of aphids. The genome assembly is based on contig and scaffold N50 values of the genome sequence are 3.77 Mb and 20.41 Mb, respectively. Nine‐seven percent of the assembled sequences was anchored onto 13 chromosomes. Based on BUSCO analysis, the assembly involved 96.9% of conserved arthropod and 98.5% of the conserved Hemiptera single‐copy orthologous genes. A total of 14,089 protein‐coding genes were predicted. Phylogenetic analysis revealed that S. chinensis diverged from the common ancestor of Eriosoma lanigerum approximately 57 million years ago (MYA). In addition, 35 genes encoding salivary gland proteins showed differentially when S. chinensis forms a gall, suggesting they have potential roles in gall formation and plant defense suppression. Taken together, this high‐quality S. chinensis genome assembly and annotation provide a solid genetic foundation for future research to reveal the mechanism of gall formation and to explore the interaction between aphids and their host plants.

Inorganic solids are a kind of important catalysts, and their activities usually come from sparse active sites, which are structurally different from inactive bulk. Therefore, the rational optimization of activity depends on studying these active sites. Copper is a widely used catalyst and is expected to be a promising catalyst for the electroreduction of CO2 to C2H4. Here, we report a conductive dinuclear cuprous complex with a short Cu···Cu contact for the electroreduction of CO2 to C2H4. By using 1H-[1,10]phenanthrolin-2-one and Cu(I) ions, a dinuclear cuprous complex [Cu2(ophen)2] (Cuophen) with a remarkable conductivity (3.9 × 10−4 S m−1) and a short intramolecular Cu···Cu contact (2.62 Å) was obtained. Such a short Cu···Cu contact is close to the distance of 2.54 Å between 2 adjacent Cu atoms in the edge of the copper(100)/(111) plane. Detailed examination of Cuophen revealed a high activity for the electroreduction of CO2 to C2H4 with a Faradaic efficiency of 55(1)% and a current density of 580 mA cm−2, and no obvious degradation was observed over 50 h of continuous operation. Comparing the properties and mechanisms of Cuophen and 2 other copper complexes with different Cu···Cu distances, we found that the shorter Cu···Cu distance is conducive not only for a *CO species to bridge 2 copper ions into a more stable intermediate transition state but also for C–C coupling.

Dense (Na0.5K0.5)NbO3 lead-free ceramics with the simple composition were prepared via sintering in low oxygen partial pressure (pO2, ∼10−12 atm) atmosphere and adding LiF. All the ceramics have pure orthorhombic structure. Compared to the LiF-added (Na0.5K0.5)NbO3 ceramics sintered in air and the low pO2-sintered pure (Na0.5K0.5)NbO3 ceramics without LiF addition, the present ceramics exhibit improved piezoelectric and ferroelectric properties. The piezoelectric constant d33 is 125 pC/N, and the converse piezoelectric constant d33* is 186 pm/V. The dielectric constant and dielectric loss of the ceramics at room temperature and 1 kHz are 451 and 0.03, respectively. Under the measured electric field of 70 kV/cm, the remanent polarization is 25.9 μC/cm2 and the coercive field is 13.9 kV/cm. Furthermore, if the base metals such as Cu and Ni powders were mixed into the green pellets and sintered in the low pO2 atmosphere, the base metals cannot be oxidized, suggesting possibility of using base metals as electrodes.

Previously, we have demonstrated that policosanol from Chinese wax suppressed testosterone(T)-induced alopecia in mice. However, the underlying mechanism remained to be determined. Herein, we investigated the mechanism of policosanol against androgenetic alopecia (AGA). AGA was induced in Kunming mice by subcutaneous administration of testosterone propionate for 60 d. Policosanol (0.5 %, 1% or 2%) was applied topically on the back of mice. Finasteride (2%) was applied topically as a positive control. The serum T and estradiol (E2) concentrations were determined by ELISA after 28 and 60 days of treatment. The cutaneous expression or activity of key mediators of hair growth, such as alkaline phosphatase (ALP), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF), was measured. MTS assay was performed to evaluate cell proliferation in cultured human dermal papilla cells (DPCs) treated with dihydrotestosterone (DHT). Western blotting was performed to evaluate the protein expression of Bax, Bcl2, TGF-β2, caspase-9, and caspase-3. We found lower T and T/E2 ratio in mice treated with policosanol than in the model group. Policosanol suppressed premature hair follicle entry into the regression phase, as shown by improving VEGF and EGF expression and ALP activity. The MTS assay showed that policosanol markedly inhibited the apoptosis of DHT-treated DPCs. Western blotting showed that policosanol significantly reduced the protein expression of TGF-β2, cleaved caspese-9, cleaved caspase-3, and Bax, and increased that of Bcl2. The optimal effect was obtained with 12.50 g/mL policosanol. In conclusion, policosanol prevents androgenetic alopecia by regulating hormone levels and suppressing premature hair follicle entry into the regression phase.

Molecular ferroelectrics have promising potential as next-generation flexible electronic materials by the advantage of flexibility, structural tunability, and easy processability. However, an obstacle in expanding their promising applications is effectively raising the ferroelectric transition temperature (Tc) necessary for practical applications, especially under high-temperature operating conditions. Herein, taking the advantage of a hydroxyl group that could form stronger hydrogen bonds to insert/tune host–guest and guest–guest interactions, we employed the 3-hydroxypyrrolidine cation to construct two new enantiomeric hexagonal perovskite ferroelectrics, (R)-3-OH-(C4H9N)[CdCl3] and (S)-3-OH-(C4H9N)[CdCl3]. Both of them undergo a ferroelectric phase transition from C2221 to P21 with a high Tc of 350 K, which is 110 K and 47 K higher than that of their parent compound (C4H10N)[CdCl3] (240 K) and F-substituted analogues (R/S)-3-F-(C4H9N)[CdCl3] (303 K), respectively. These findings well demonstrate that, besides the F-substitution strategy, an OH-substitution strategy provides an important and practical way in designing high-Tc ferroelectrics.

Lead (Pb) can cause a significant neurotoxicity in both adults and children, leading to the impairment to brain function. Pb exposure plays a key role in the impairment of learning and memory through synaptic neurotoxicity, resulting in the cognitive function. Researches have demonstrated that Pb exposure plays an important role in the etiology and pathogenesis of neurodegenerative diseases, such as Alzheimer’s disease. However, the underlying mechanisms remain unclear. In the current study, a gestational Pb exposure (GLE) rat model was established to investigate the underlying mechanisms of Pb-induced cognitive impairment. We demonstrated that low-level gestational Pb exposure impaired spatial learning and memory as well as hippocampal synaptic plasticity at postnatal day 30 (PND 30) when the blood concentration of Pb had already recovered to normal levels. Pb exposure induced a decrease in hippocampal glucose metabolism by reducing glucose transporter 4 (GLUT4) levels in the cell membrane through the phosphatidylinositol 3 kinase-protein kinase B (PI3K-Akt) pathway. In vivo and in vitro GLUT4 over-expression increased the membrane translocation of GLUT4 and glucose uptake, and reversed the Pb-induced impairment to synaptic plasticity and cognition. These findings indicate that Pb exposure impairs synaptic plasticity by reducing the level of GLUT4 in the cell membrane as well as glucose uptake via the PI3K-Akt signaling pathway, demonstrating a novel mechanism for Pb exposure-induced neurotoxicity.

Understanding the hydrate adhesion is important to tackling hydrate accretion in petro-pipelines. Herein, the relationship between the Tetrahydrofuran (THF) hydrate adhesion strength (AS) and surface stiffness on elastic coatings is systemically examined by experimental shear force measurements and theoretical methods. The mechanical factor-elastic modulus of the coatings greatly dictates the hydrate AS, which is explained by the adhesion mechanics theory, beyond the usual factors such as wettability and structural roughness. Moreover, the hydrate AS increases with reducing the thickness of the elastic coatings, resulted from the decrease of the apparent surface elastic modulus. The effect of critical thickness for the elastic materials with variable elastic modulus on the hydrate AS is also revealed. This study provides deep perspectives on the regulation of the hydrate AS by the elastic modulus of elastic materials, which is of significance to design anti-hydrate surfaces for mitigation of hydrate accretion in petro-pipelines. [ABSTRACT FROM AUTHOR]

Understanding, controlling, and utilizing the flexibility of adsorbents are of great importance and difficulty. Analogous with conventional solid materials, downsizing to the nanoscale is emerging as a possible strategy for controlling the flexibility of porous coordination polymers (or metal-organic frameworks). We report a unique flexibility controllable by crystal size at the micrometer to submillimeter scale. Template removal transforms [Cu2(pypz)2]·0.5p-xylene (MAF-36, Hpypz = 4-(1H-pyrazol-4-yl)pyridine) with one-dimensional channels to α-[Cu2(pypz)2] with discrete small cavities, and further heating gives a nonporous isomer β-[Cu2(pypz)2]. Both isomers can adsorb p-xylene to give [Cu2(pypz)2]·0.5p-xylene, meaning the coexistence of guest-driven flexibility and shape-memory behavior. The phase transition temperature from α-[Cu2(pypz)2] to β-[Cu2(pypz)2] decreased from ~270°C to ~150°C by increasing the crystal size from the micrometer to the submillimeter scale, ca. 2-3 orders larger than those of other size-dependent behaviors. Single-crystal X-ray diffraction showed coordination bond reconstitution and chirality inversion mechanisms for the phase transition, which provides a sufficiently high energy barrier to stabilize the metastable phase without the need of downsizing to the nanoscale. By virtue of the crystalline molecular imprinting and gate-opening effects, α-[Cu2(pypz)2] and β-[Cu2(pypz)2] show unprecedentedly high p-xylene selectivities of 16 and 51, respectively, as well as ultrafast adsorption kinetics (