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Decoupled parallel x y z positioning stages with a large stroke are desired in high-speed and precise positioning applications. However, currently, such stages either have a short stroke or are unqualified in terms of the parasitic motion and coupling rate. In this paper, a novel flexure-based decoupled parallel x y z positioning stage (FlexDelta) is proposed and its conceptual design, modeling, and experimental investigation are conducted. First, the working principle of FlexDelta is introduced, followed by the design of its mechanism with flexure. Second, the stiffness model of flexure is established using matrix-based Castigliano's second theorem, and the influence of its lateral stiffness on the stiffness model of FlexDelta is comprehensively investigated and then optimally designed. Finally, experiments were conducted using the fabricated prototype. The results reveal that the positioning stage features a centimeter stroke in three axes, with a coupling rate of less than 0.53% and parasitic motion of less than 1.72 mrad over the full range. Its natural frequencies are 20.8 Hz, 20.8 Hz, and 22.4 Hz for the x , y , and z axis, respectively. Multi-axis path-tracking tests were also performed, which validated its dynamic performance with a micrometer error. • Featuring the highest compactness ratio (4. 65 × 1 0 − 4 ) among relevant works. • Small coupling rate (0.53%) and parasitic motion (1.72 mrad) over full range. • Analysis on influence of lateral stiffness on FlexDelta and optimal design. • Comprehensive experimental study on FlexDelta validates its high performance. [ABSTRACT FROM AUTHOR]

Quench detection is vital for the safe operation of insulated high-temperature superconducting (HTS) magnets. However, due to slow quench propagation and susceptibility of terminal voltage to current interference, it is difficult to detect quench for an insulated HTS magnet. Co-wound tape (CWT) compensation method and the balance bridge (BB) compensation method show improvements to the voltage method. Both methods can eliminate the noise generated by induced voltage with fast response and high convenience. In this work, the CWT compensation method and BB compensation method are used to study the quench detection of an insulated HTS magnet under various operating conditions. CWT compensation and BB compensation methods, having a signal-to-noise ratio of 45 and 39 dB, respectively, outperform the conventional voltage detection method (− 13 dB). [ABSTRACT FROM AUTHOR]

This paper presents the design, modeling, analysis, and test of a 2-degree-of-freedom (2-DOF) high-precision parallel pointing mechanism capable of carrying a heavy load up to 30 N ⋅ m driven by high voltage piezo-stack actuators (HVPSAs). The proposed pointing mechanism, which employs flexure hinges as joints, provides two tilting degrees of freedom and can be utilized for intersatellite optical communication, remote sensing satellite lens pointing, and other engineering fields requiring large load capability. In this paper different kinds of flexure hinges are utilized to achieve the desired motion and working performance. With consideration of most compliant elements, Castigliano's second theorem was adopted to establish the analytical static model of the mechanism, which was then validated by FEA simulation and experimental testing. Finally, a high-precision pointing prototype is fabricated and a series of motion performance tests have been implemented, which validated the feasibility of the proposed system. The superiority of the proposed design is that it possesses large load capacity as well as excellent pointing performance simultaneously, while the former characteristic was infrequently reported in previous works. • Design process of the 2-DOF parallel pointing mechanism is presented. • Castigliano's second theorem was adopted to establish the analytical static model. • Large load capacity up to 30 Nm is achieved by the proposed pointing mechanism. • High precision with resolution of 0.7 μ rad and pointing accuracy of 1.09 μ rad (3 σ). [ABSTRACT FROM AUTHOR]

A series of SmFeAsO1-xFx (Sm1111) tapes were fabricated by the ex situ powder-in-tube (PIT) method. A powder-impregnated post-rolling sintering (PRS) process was applied to the Sm1111 tapes to suppress the loss of F element in the tapes during PRS. By this method, the Sm1111 tapes can endure long-time sintering at 850 ℃ without Tc degradation. A series of Sm1111 tapes with high transition temperature (> 50 K) were obtained. EPMA analysis reveals that the superconducting cores in tapes after this PRS process have the similar F concentration with the Sm1111 precursor bulk. [ABSTRACT FROM AUTHOR]

In the semi-hydrogenation of acetylene, nickel-based catalysts offer a promising alternative to precious metal palladium catalysts. Despite the positive hydrogenation activity of nickel-based catalysts, there is still room for improvement in terms of their selectivity and stability. In this study, a simple incipient wetness impregnation method was employed to prepare Ni(OAC) 2 -IL/Al 2 O 3 catalyst and its performance in the selective hydrogenation of acetylene was investigated. It was found that under the conditions of 170 °C and a space velocity of 600 h−1, the 3 % Ni(OAC) 2 -IL/Al 2 O 3 catalyst achieved a 95.3 % acetylene conversion with an 85.6 % ethylene selectivity. Furthermore, the catalyst exhibited outstanding stability over a 100 hour test. TEM, XPS and C 2 H 4 -TPD experiments showed that the Ni species were encapsulated in the ionic liquids (ILs), and the interaction between the metal ions, nickel, and the ILs ensured a high dispersion and stability of the actives on the carriers, and the electronic effect between the ionic nickel and the ionic liquids increased the electron cloud density of the Ni, which improved the catalyst selectivity, which is the main reason for its excellent catalytic performance. [Display omitted] • The Ni(OAC) 2 -IL /Al 2 O 3 catalyst was synthesized via a incipient wetness impregnation method. • Ni(OAC) 2 -IL /Al 2 O 3 catalysts showed higher ethylene selectivity (>85 %) and stability. • The interaction of the metal ion nickel with IL ensured high dispersion and stability of the active substance on the carrier. [ABSTRACT FROM AUTHOR]

• Complex formation between cucurbit[ n ]uril(n = 7,8) hosts and chlorzoxazone guest. • The host-guest interaction was studied by single-crystal X-ray diffraction spectroscopy, isothermal titration calorimetry (ITC), UV–vis spectroscopy and 1H NMR spectroscopy. • CHZ and Q[7] form a 1:1 host-guest inclusion complex, and CHZ and Q[8] form a 2:1 host-guest inclusion complex. • After the addition of Q[7], the water solubility of CHZ is improved, and the addition of Q[8] basically does not affect the water solubility of CHZ. • The formation of complex host-guest inclusion complexes will not affect the stability of CHZ itself. The interaction between cucurbit[ n ]uril (n = 7,8, Q[ n ]s) and chlorzoxazone (CHZ) was investigated using single-crystal X-ray diffraction spectroscopy, isothermal titration calorimetry (ITC), UV–vis spectroscopy and 1H NMR spectroscopy. The effects of cucurbit[ n ]uril (n = 7,8) on the stability, water solubility and CHZ in vitro release performance were also studied. The results showed that CHZ and Q[8] formed a 2:1 inclusion complex (CHZ 2 @Q[8]) with a binding constant of 6.971 × 104 L·mol−2 and CHZ and Q[7] formed a 1:1 inclusion complex (CHZ@Q[7]) with a binding constant of 9.546 × 104 L·mol−1. The intervention of cucurbit[ n ]uril (n = 7,8) prolonged the CHZ release time in artificial gastric and intestinal juices and increased the solubility of CHZ in aqueous solution while hardly affecting the stability. [ABSTRACT FROM AUTHOR]

Polycrystalline Sn-added SmFeAsO1-xFx tapes were prepared by an ex-situ powder-in-tube method. It is found that the transport critical current density (Jc) of the SmFeAsO1-xFx tapes can be significantly improved with 10-30 wt. % Sn addition. A transport Jc of 2.11 × 104 A cm-2 at 4.2 K in self-field was obtained in SmFeAsO1-xFx + 30 wt. % Sn sample. Most interestingly, Sn-added SmFeAsO1-xFx tapes without any sintering also showed substantial transport Jc of 9.81 × 103 A cm-2, which is reported for the first time. X-ray diffraction and scanning electron microscopy characterization revealed that the elemental Sn dispersed in the sample transformed into FeSn2 during the post-rolling sintering (PRS). The reaction between Sn and FeAs helps to eliminate the detrimental FeAs wetting phase, which blocks the supercurrent path between SmFeAsO1-xFx grains. The combined impact of fluorine loss and Sn reaction was discussed in this work by varying the Sn addition quantity and PRS condition. [ABSTRACT FROM AUTHOR]

Honeycomb ceramic absorbers are considered to be one of the most practical options for the air receiver of a solar central receiver plant. To explore the influence of the average input solar heat flux, air flow rate, and absorber geometric parameters on the honeycomb ceramic air receiver performance, six samples were tested under different conditions and the outlet air temperature, thermal efficiency, and anti-interference characteristics of the receivers were determined. The investigation showed that as the input solar flux or air flow rate increased, the change in the outlet air temperature and thermal efficiency had opposite trends. The sample with the shortest length, thinnest wall, and highest porosity had the best performance. Among the three absorber geometry parameters, the porosity was the dominant factor affecting the receiver outlet temperature and thermal efficiency. [ABSTRACT FROM AUTHOR]

Acetylene semi-hydrogenation reaction is a critical transformation process for removing trace levels of acetylene from industrial ethylene streams. Noble metal catalysts are commonly used for this process; however, their high cost and limited availability hinder large-scale and long-term applications. Non-metallic catalysts, on the contrary, exhibit multiple benefits in acetylene hydrogenation, including higher activity, greater selectivity, and environmental friendliness. This review primarily discusses the use of non-metallic catalysts in acetylene hydrogenation, such as metal oxides, nitrides, and carbon compounds. The emphasis is on the catalytic mechanism and critical steps of non-metallic catalysts based on frustrated Lewis pairs (FLP), including the adsorption and activation of hydrogen and acetylene, as well as ethylene production. In addition, research work on catalyst design and reaction condition modification to improve conversion rate and product selectivity is discussed. Finally, the future development directions of non-metallic catalyzed acetylene hydrogenation are reviewed, including further mechanistic investigations, the study of novel catalytic systems, and the implementation of environmentally friendly chemical processes. It is envisaged that non-metallic catalyzed acetylene hydrogenation would play a key role in energy conversion and the chemical sector, contributing to long-term sustainability. [Display omitted] • Acetylene semi-hydrogenation is key in fine chemical and polymer production. • Affordable and effective metal-free catalysts exist. • Frustrated Lewis pairs enable metal-free catalysis. • A wide range of metal-free catalysts sparks innovation. [ABSTRACT FROM AUTHOR]

• The porosity of rock samples increases with the number of freeze–thaw cycles, while static and dynamic fracture toughness decreases, indicating that freeze–thaw cycles degrade the microstructure and adversely affect the mechanical properties. • The fractal dimensions increased with the freeze–thaw cycles increased. The freeze–thaw effect increases the roughness of fracture surface, which corresponds to the decrease of fracture toughness. • The dynamic fracture toughness increases with the increase of loading rate. This indicates that the freeze–thaw rock under high dynamic load has greater fracture resistance than that under slow dynamic load. In this study, the dynamic fracture toughness of freeze-thawed granite was studied. Different freeze–thaw (F-T) cycles were used to treat notched semicircular bending (NSCB) granite samples. The microstructure changes of samples treated with different numbers of F-T cycles were measured by a nuclear magnetic resonance (NMR) testing system. The dynamic fracture toughness was obtained by dynamic testing with split Hopkinson pressure bar (SHPB) equipment. In addition, the roughness of the rock fracture surface was studied using fractal geometry, and the F-T damage was defined using fractal dimensions. On this basis, a dynamic fracture toughness prediction model is proposed. The influence of the F-T cycle and loading rate on fracture toughness are discussed. [ABSTRACT FROM AUTHOR]

• A design method increasing the amplification ratio of the amplifier was proposed. • Dual-drive system was introduced to balance the large stroke and fine resolution. • A displacement amplifier with stroke of 6 mm and resolution of 20 nm is proposed. • The "kick-back" phenomenon is first analyzed and eliminated. This paper presents the design, modelling, analysis, and test of a piezo-actuated dual-drive linear motion system, capable of millimeter stroke with nanometer resolution. The primary actuator is a two-stage bridge-type amplifier with hybrid flexure hinges, which is driven by a piezo-stack actuator and generates output stroke greater than 6 mm. The micro actuation is directly driven by an extra piezo-stack to achieve resolution of 20 nm. A very large amplification ratio of 91 is achieved, which implies not only large stroke but also compactness. An inherent characteristic for the multi-stage compliant displacement amplifier, 'kick-back' phenomenon, is first analyzed and eliminated by using the stiffness distribution method. The architectural parameters are optimized by genetic algorithm to find the trade-off among natural frequency, stroke and stiffness ratio. The optimized design was then fabricated and tested. The superiority of the proposed system is remarkable compared with other similar works. The concept and approach outlined are generic and can be extended to this class of actuators. [ABSTRACT FROM AUTHOR]

• The porosity of rock samples increases with the number of freeze–thaw cycles, while static and dynamic fracture toughness decreases, indicating that freeze–thaw cycles degrade the microstructure and adversely affect the mechanical properties. • The fractal dimensions increased with the freeze–thaw cycles increased. The freeze–thaw effect increases the roughness of fracture surface, which corresponds to the decrease of fracture toughness. • The dynamic fracture toughness increases with the increase of loading rate. This indicates that the freeze–thaw rock under high dynamic load has greater fracture resistance than that under slow dynamic load. In this study, the dynamic fracture toughness of freeze-thawed granite was studied. Different freeze–thaw (F-T) cycles were used to treat notched semicircular bending (NSCB) granite samples. The microstructure changes of samples treated with different numbers of F-T cycles were measured by a nuclear magnetic resonance (NMR) testing system. The dynamic fracture toughness was obtained by dynamic testing with split Hopkinson pressure bar (SHPB) equipment. In addition, the roughness of the rock fracture surface was studied using fractal geometry, and the F-T damage was defined using fractal dimensions. On this basis, a dynamic fracture toughness prediction model is proposed. The influence of the F-T cycle and loading rate on fracture toughness are discussed. [ABSTRACT FROM AUTHOR]

Abstract: By generating the monodisperse droplets of disperse phase in the continuous phase and keeping them stable during condensing process, it is possible to fabricate monodisperse spherical condensates using emulsification–diffusion technique. In this work we fabricated the monodispersive polylysine micro- and nano-spheres by using “flow-focusing” and droplets diffusion techniques. By keeping the flow rates of dispersed phase and continuous phase constant, the size of condensed and glutaraldehyde cross-linked polylysine spherical particles was tuned from tens micrometers to tens nanometers by varying the concentration of the polylysine solution. Near monodisperse spheres can form from tens micrometers to hundreds nanometers with similar size distribution. The luminescence experiment shows that the stability of small molecules trapped by cross-linked polymer can be stable over tens hours when sufficient aldehydization keeps the condensates stable. [Copyright &y& Elsevier]

Purpose: This study aimed to identify the genetic causes of male infertility and primary ciliary dyskinesia (PCD)/PCD-like phenotypes in three unrelated Han Chinese families. Methods: We conducted whole-exome sequencing of three patients with male infertility and PCD/PCD-like phenotypes from three unrelated Chinese families. Ultrastructural and immunostaining analyses of patient spermatozoa and respiratory cilia and in vitro analyses were performed to analyze the effects of SPEF2 variants. Intracytoplasmic sperm injection (ICSI) was administered to three affected patients. Results: We identified four novel SPEF2 variants, including one novel homozygous splicing site variant [NC_000005.10(NM_024867.4): c.4447 + 1G > A] of the SPEF2 gene in family 1, novel compound heterozygous nonsense variants [NC_000005.10(NM_024867.4): c.1339C > T (p.R447*) and NC_000005.10(NM_024867.4): c.1645G > T (p.E549*)] in family 2, and one novel homozygous missense variant [NC_000005.10(NM_024867.4): c.2524G > A (p.D842N)] in family 3. All the patients presented with male infertility and PCD/likely PCD. All variants were present at very low levels in public databases, predicted to be deleterious in silico prediction tools, and were further confirmed deleterious by in vitro analyses. Ultrastructural analyses of the spermatozoa of the patients revealed the absence of the central pair complex in the sperm flagella. Immunostaining of the spermatozoa and respiratory cilia of the patients validated the pathogenicity of the SPEF2 variants. All patients carrying SPEF2 variants underwent one ICSI cycle and delivered healthy infants. Conclusion: Our study reported four novel pathogenic variants of SPEF2 in three male patients with infertility and PCD/PCD-like phenotypes, which not only extend the spectrum of SPEF2 mutations but also provide information for genetic counseling and treatment of such conditions. [ABSTRACT FROM AUTHOR]

Purpose: To identify the genetic causes of multiple morphological abnormalities in sperm flagella (MMAF) and male infertility in patients from two unrelated Han Chinese families. Methods: Whole-exome sequencing was conducted using blood samples from the two individuals with MMAF and male infertility. Hematoxylin and eosin staining and scanning electron microscopy were performed to evaluate sperm morphology. Ultrastructural and immunostaining analyses of the spermatozoa were performed. The HEK293T cells were used to confirm the pathogenicity of the variants. Results: We identified two novel homozygous missense ARMC2 variants: c.314C > T: p.P105L and c.2227A > G: p.N743D. Both variants are absent or rare in the human population genome data and are predicted to be deleterious. In vitro experiments indicated that both ARMC2 variants caused a slightly increased protein expression. ARMC2-mutant spermatozoa showed multiple morphological abnormalities (bent, short, coiled, absent, and irregular) in the flagella. In addition, the spermatozoa of the patients revealed a frequent absence of the central pair complex and disrupted axonemal ultrastructure. Conclusion: We identified two novel ARMC2 variants that caused male infertility and MMAF in Han Chinese patients. These findings expand the mutational spectrum of ARMC2 and provide insights into the complex causes and pathogenesis of MMAF. [ABSTRACT FROM AUTHOR]

Purpose: The preimplantation genetic testing for aneuploidy (PGT-A) platform is not currently available for small copy-number variants (CNVs), especially those < 1 Mb. Through strategies used in PGT for monogenic disease (PGT-M), this study intended to perform PGT for families with small pathogenic CNVs. Methods: Couples who carried small pathogenic CNVs and underwent PGT at the Reproductive and Genetic Hospital of CITIC-Xiangya (Hunan, China) between November 2019 and April 2023 were included in this study. Haplotype analysis was performed through two platforms (targeted sequencing and whole-genome arrays) to identify the unaffected embryos, which were subjected to transplantation. Prenatal diagnosis using amniotic fluid was performed during 18–20 weeks of pregnancy. Results: PGT was successfully performed for 20 small CNVs (15 microdeletions and 5 microduplications) in 20 families. These CNVs distributed on chromosomes 1, 2, 6, 7, 13, 15, 16, and X with sizes ranging from 57 to 2120 kb. Three haplotyping-based PGT-M strategies were applied. A total of 89 embryos were identified in 25 PGT cycles for the 20 families. The diagnostic yield was 98.9% (88/89). Nineteen transfers were performed for 17 women, resulting in a 78.9% (15/19) clinical pregnancy rate after each transplantation. Of the nine women who had healthy babies, eight accepted prenatal diagnosis and the results showed no related pathogenic CNVs. Conclusion: Our results show that the extended haplotyping-based PGT-M strategy application for small pathogenic CNVs compensated for the insufficient resolution of PGT-A. These three PGT-M strategies could be applied to couples with small pathogenic CNVs. [ABSTRACT FROM AUTHOR]

Multiple morphological abnormalities of the sperm flagella (MMAF)-induced asthenoteratozoospermia is a common cause of male infertility. Previous studies have identified several MMAF-associated genes, highlighting the condition's genetic heterogeneity. To further define the genetic causes underlying MMAF, we performed whole-exome sequencing in a cohort of 643 Chinese MMAF-affected men. Bi-allelic DNAH10 variants were identified in five individuals with MMAF from four unrelated families. These variants were either rare or absent in public population genome databases and were predicted to be deleterious by multiple bioinformatics tools. Morphological and ultrastructural analyses of the spermatozoa obtained from men harboring bi-allelic DNAH10 variants revealed striking flagellar defects with the absence of inner dynein arms (IDAs). DNAH10 encodes an axonemal IDA heavy chain component that is predominantly expressed in the testes. Immunostaining analysis indicated that DNAH10 localized to the entire sperm flagellum of control spermatozoa. In contrast, spermatozoa from the men harboring bi-allelic DNAH10 variants exhibited an absence or markedly reduced staining intensity of DNAH10 and other IDA components, including DNAH2 and DNAH6. Furthermore, the phenotypes were recapitulated in mouse models lacking Dnah10 or expressing a disease-associated variant, confirming the involvement of DNAH10 in human MMAF. Altogether, our findings in humans and mice demonstrate that DNAH10 is essential for sperm flagellar assembly and that deleterious bi-allelic DNAH10 variants can cause male infertility with MMAF. These findings will provide guidance for genetic counseling and insights into the diagnosis of MMAF-associated asthenoteratozoospermia. [ABSTRACT FROM AUTHOR]

In this work, an 'on-off' fluorescent probe was developed for detection of acid protease (ACP) based on bovine serum albumin (BSA) as the substrate. 3,3′-Dipentylthiacarbocyanine iodide, DiSC 5 (3), exhibits very weak fluorescence emission in aqueous solution, but following the addition of BSA, due to hydrophobic interactions between them, DiSC 5 (3) forms an aggregate with BSA and emits strong red fluorescence. When ACP is added, the fluorescence emission of the DiSC 5 (3)-BSA system is quenched because BSA is hydrolysed into peptide fragments and amino acids by ACP, destroying the DiSC 5 (3)-BSA system. The degree of fluorescence quenching of the DiSC 5 (3)-BSA system is proportional to the concentration of ACP over a range of 10–40 μg/mL, with a linear equation y = −4.8270 x + 509.7066, a correlation coefficient R 2 = 0.9986, and a detection limit of 1.44 μg/mL. The method has advantages including simple operation, high sensitivity and good selectivity, and can be used for detection of ACP in real samples. [Display omitted] • 3,3′-Dipentylthiacarbocyanine iodide, DiSC 5 (3), can react with bovine serum albumin (BSA) to emit strong red fluorescence. • Acid protease can significantly quench the fluorescence of DiSC 5 (3)- BSA. • DiSC 5 (3)- BSA can be used as fluorescent probe to detect acid protease. [ABSTRACT FROM AUTHOR]

Stibnite mineral (mainly Sb2S3) has been employed for the synthesis of tetrahedrite Cu12Sb4S13 bulk material by spark plasma sintering. High purity Cu12Sb4S13 can be quickly obtained by two sintering procedures at temperatures from the range of 420 °C to 440 °C for 1 h. Appropriate reduction of Cu content (Cu12+xSb4S13, x ⩽ –0.05) or CuS content (Cu12−ySb4S13−y, y = 0.1 or 0.3) was beneficial to fabricate Cu12Sb4S13. The secondary resintering improved the purity of Cu12Sb4S13 material. The first-order magnetic phase transformation with magnetic hysteresis effect was confirmed by the behavior of susceptibility, heat capacity and resistivity. The magnetization showed a linear increase with increasing field (up to 7 T) and non-saturation behavior was observed. The impurities in stibnite mineral Sb2S3 had a weak influence on the transformation temperature but affected the low-temperature magnetization value (~0.15, close to natural tetrahedrite). Similar transformation was observed by the analysis of heat capacity. The properties such as electrical resistivity, Seebeck coefficient and thermal conductivity were also measured for Cu11:9Sb4S13 and Cu11:9Sb4S12:9. The maximum figure of merit ZT of Cu11:9Sb4S12:9 was 0.22 at 367 K. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Can whole-exome sequencing (WES) reveal new genetic factors responsible for male infertility characterized by oligozoospermia? SUMMARY ANSWER We identified biallelic missense variants in the Potassium Channel Tetramerization Domain Containing 19 gene (KCTD19) and confirmed it to be a novel pathogenic gene for male infertility. WHAT IS KNOWN ALREADY KCTD19 is a key transcriptional regulator that plays an indispensable role in male fertility by regulating meiotic progression. Kctd19 gene-disrupted male mice exhibit infertility due to meiotic arrest. STUDY DESIGN, SIZE, DURATION We recruited a cohort of 536 individuals with idiopathic oligozoospermia from 2014 to 2022 and focused on five infertile males from three unrelated families. Semen analysis data and ICSI outcomes were collected. WES and homozygosity mapping were performed to identify potential pathogenic variants. The pathogenicity of the identified variants was investigated in silico and in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS Male patients diagnosed with primary infertility were recruited from the Reproductive and Genetic Hospital of CITIC-Xiangya. Genomic DNA extracted from affected individuals was used for WES and Sanger sequencing. Sperm phenotype, sperm nuclear maturity, chromosome aneuploidy, and sperm ultrastructure were assessed using hematoxylin and eosin staining and toluidine blue staining, FISH and transmission electron microscopy. The functional effects of the identified variants in HEK293T cells were investigated via western blotting and immunofluorescence. MAIN RESULTS AND THE ROLE OF CHANCE We identified three homozygous missense variants (NM_001100915, c.G628A:p.E210K, c.C893T:p.P298L, and c.G2309A:p.G770D) in KCTD19 in five infertile males from three unrelated families. Abnormal morphology of the sperm heads with immature nuclei and/or nuclear aneuploidy were frequently observed in individuals with biallelic KCTD19 variants, and ICSI was unable to rescue these deficiencies. These variants reduced the abundance of KCTD19 due to increased ubiquitination and impaired its nuclear colocalization with its functional partner, zinc finger protein 541 (ZFP541), in HEK293T cells. LIMITATIONS, REASONS FOR CAUTION The exact pathogenic mechanism remains unclear, and warrants further studies using knock-in mice that mimic the missense mutations found in individuals with biallelic KCTD19 variants. WIDER IMPLICATIONS OF THE FINDINGS Our study is the first to report a likely causal relationship between KCTD19 deficiency and male infertility, confirming the critical role of KCTD19 in human reproduction. Additionally, this study provided evidence for the poor ICSI clinical outcomes in individuals with biallelic KCTD19 variants, which may guide clinical treatment strategies. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the National Key Research and Developmental Program of China (2022YFC2702604 to Y.-Q.T.), the National Natural Science Foundation of China (81971447 and 82171608 to Y.-Q.T. 82101961 to C.T.), a key grant from the Prevention and Treatment of Birth Defects from Hunan Province (2019SK1012 to Y.-Q.T.), a Hunan Provincial Grant for Innovative Province Construction (2019SK4012), and the China Postdoctoral Science Foundation (2022M721124 to W.W.). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Male infertility affects approximately 7% of childbearing couples and is a major health issue. Although nearly 50% idiopathic infertile men are assumed to have a genetic basis, the underlying causes remain largely unknown in most infertility cases. Here, we report two rare homozygous variants in two previously uncharacterized genes, C9orf131 and C10orf120 , identified in two unrelated men with asthenozoospermia. Both genes were predominantly expressed in the testes. Furthermore, C9orf131 and C10orf120 knockout mice were successfully generated using the CRISPR-Cas9 technology. However, both C9orf131 −/− and C10orf120 −/− adult male mice were fertile, with testis-to-body weight ratios comparable to those of wild-type mice. No overt differences were found between wild-type, C9orf131 −/−, and C10orf120 −/− mice regarding testicular/epididymal tissue morphology, sperm count, sperm motility, or sperm morphology. Moreover, TUNEL assays indicated that the number of apoptotic germ cells in testes was not significantly different between the three groups. In summary, these findings suggest that C9orf131 and C10orf120 are redundant genes in male infertility. [Display omitted] • C9orf131 and C10orf120 are highly expressed in the testes. • C9orf131 knockout male mice were viable, with normal fertility and spermatogenesis. • C10orf120 knockout male mice were viable, with normal fertility and spermatogenesis. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to identify the genetic cause of primary ciliary dyskinesia (PCD) and male infertility in two unrelated Han Chinese families. Methods: We performed whole-exome sequencing in two unrelated male Han Chinese patients suffering from infertility and PCD to identify the pathogenic variants. Ultrastructural and immunostaining analyses of patient's spermatozoa were performed to characterize the effect of the variants. The pathogenicity of the variants was validated using patient's spermatozoa by western blotting and immunostaining analysis. Intracytoplasmic sperm injection (ICSI) was conducted in the affected families. Results: Three variants in leucine-rich repeat containing 6 (LRRC6) [patient 1(compound heterozygote): NM_012472: c.538C > T, (p.R180*) and c.64dupT, (p.S22Ffs*19); patient 2 (homozygote): c.863C > A, (p.P288H)] were identified in two unrelated patients with PCD and male infertility. These variants were predicated deleterious and were absent or rare in human population genome data. LRRC6-mutant spermatozoa showed a highly aberrant morphology and ultrastructure with lacked inner and outer dynein arms. The LRRC6 protein was present along the normal sperm flagella, and was significantly decreased in the mutated spermatozoa. Interestingly, both patients were able to conceive through ICSI and birthed a healthy baby. Conclusion: Our results extend the LRRC6 variant spectrum and provide reproductive guidance to families suffering from PCD-linked infertility caused by LRRC6 variants. [ABSTRACT FROM AUTHOR]

Since a conceptor, achieving direction‐selective damping of high‐dimensional network signals, usually takes the form of a projection matrix and is deduced analytically, a conceptor‐based neural network is thought to be untrainable with backpropagation and gradient‐descent algorithms from end to end. It limits the application of conceptors. To address this issue, an algorithm is proposed to train conceptor‐based neural networks from end to end with gradient‐descent algorithms. To the best of the authors' knowledge, it is the first work of such an end‐to‐end training algorithm. To develop this algorithm, a softmax‐like loss function involved with conceptors is constructed empirically. Based on this loss function, corresponding gradients are deduced by using backpropagation method so that it is possible to train conceptor neural networks from end to end with a gradient‐descent algorithm. Several experiments are conducted to show the feasibility and effectiveness of the proposed training algorithm. [ABSTRACT FROM AUTHOR]

Keywords: asthenoteratozoospermia; CCIN; ICSI; male infertility; WES EN asthenoteratozoospermia CCIN ICSI male infertility WES 495 497 3 03/03/23 20230401 NES 230401 (A) Characteristics of spermatozoa in asthenoteratozoospermia affected man. (B) Pedigree and Sanger sequencing analysis of the family. To evaluate the functional effects of the I CCIN i missense variant, immunostaining of spermatozoa showed that CCIN was localized in the equatorial region and calyx of the sperm head in the control subjects, whereas it was almost absent and only diffusely clustered in the I CCIN i mutant sperm head (Figure 1G). [Extracted from the article]

Background: Emerging evidence suggest the critical role of circular RNAs (circRNAs) in disease development especially in various cancers. However, the oncogenic role of circRNAs in hepatocellular carcinoma (HCC) is still largely unknown. Methods: RNA sequencing was performed to identify significantly upregulated circRNAs in paired HCC tissues and non-tumor tissues. CCK-8 assay, colony formation, transwell, and xenograft mouse models were used to investigate the role of circRNAs in HCC proliferation and metastasis. Small interfering RNA (siRNA) was used to silence gene expression. RNA immunoprecipitation, biotin pull-down, RNA pull-down, luciferase reporter assay and western blot were used to explore the underlying molecular mechanisms. Results: Hsa_circ_0095868, derived from exon 5 of the MDK gene (named circMDK), was identified as a new oncogenic circRNA that was significantly upregulated in HCC. The upregulation of circMDK was associated with the modification of N6-methyladenosine (m6A) and poor survival in HCC patients. Mechanistically, circMDK sponged miR-346 and miR-874-3p to upregulate ATG16L1 (Autophagy Related 16 Like 1), resulting to the activation of PI3K/AKT/mTOR signaling pathway to promote cell proliferation, migration and invasion. Poly (β-amino esters) (PAEs) were synthesized to assist the delivery of circMDK siRNA (PAE-siRNA), which effectively inhibited tumor progression without obvious adverse effects in four liver tumor models including subcutaneous, metastatic, orthotopic and patient-derived xenograft (PDX) models. Conclusions: CircMDK could serve as a potential tumor biomarker that promotes the progression of HCC via the miR-346/874-3p-ATG16L1 axis. The PAE-based delivery of siRNA improved the stability and efficiency of siRNA targeting circMDK. The PAE-siRNA nanoparticles effectively inhibited HCC proliferation and metastasis in vivo. Our current findings offer a promising nanotherapeutic strategy for the treatment of HCC. [ABSTRACT FROM AUTHOR]

In this study, cucurbit[8]uril (Q[8]) was used as a carrier for Sulfanilamide (G1) and sulfamethoxazole (G2), and the crystals of their inclusion complexes were cultured in a 3M HCl aqueous solution upon the addition of ZnCl2 as an inducer. The crystal structure was characterized using single-crystal X-ray diffraction. The results showed that two new supramolecular self-assemblies were constructed and the main driving forces in the system were hydrogen bond and ion–dipole interactions. In addition, the effects of Q[8] on the solubility and cumulative release rate in vitro of G1 and G2 were investigated by UV Vis spectroscopy. The results showed that the intervention of Q[8] had no effect on the solubility of G1 and G2; the cumulative release rates of G1 and G2 in artificial gastrointestinal juice were reduced and had a certain sustained-release effect. In this study, we reported that Cucurbit[8]uril (Q[8]) was used as the carrier of P-aminobenzenesulfonamide and sulfamethoxazole. The experimental results show that the main driving forces of the system are hydrogen bond and ion-dipole interaction and two new supramolecular self-assemblers were constructed. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS), as a label-free, highly sensitive analytical method, has become an important tool for providing substance fingerprints. In this study, silver nanoparticles containing thiosulfate ions and calcium ions (Ag@SCNPs) have been used as an enhanced substrate to eliminate the interference of impurities on DNA signals. Intrinsic structural information on single-strand DNA (ssDNA) was directly obtained through SERS. The improved enhancement system was used to explore the base-stacking rules of ssDNA in a solution environment. For the first time, single-base insertion mutations and deletion mutations, as well as their exact mutation sites, were identified, and Raman spectra with high stability, repeatability, and high signal-to-noise ratio were obtained. The method is simple, fast, and accurate, and the detection process is nondestructive. It has potential to be applied in the fields of medical diagnosis and genetics research. [ABSTRACT FROM AUTHOR]

Designing multifunctional cathode materials is essential to address the critical issues of poor cycle stability and sluggish reaction kinetics in the aqueous zinc-ion batteries (AZIBs). Here, the spinel-type bimetallic MnCo 2 O 4 with a porous, layered, irregular cubic structure was synthesized using hydrothermal method, which was employed as a cathode material for high performance AZIBs. The design strategy involving bimetallic oxides offers more electrochemically active sites than monometallic oxides. Simultaneously, the unique porous structure of MnCo 2 O 4 facilitates faster ions and electrons transport, which alleviates the problems of volume expansion and structural collapse that occurring in the cathode material during cycling. As a result, the MnCo 2 O 4 electrode exhibits superior zinc storage performance with a high reversible specific capacity of 332.1 mAh g−1 and excellent cycle stability after 65 cycles at a current density of 0.3 A g−1. [Display omitted] • Irregular bimetallic MnCo 2 O 4 cubic structure with porous layered stacking were obtained by hydrothermal method. • MnCo 2 O 4 electrodes have both exceptional specific capacity and excellent cycling stability. • The Zn storage mechanism of MnCo 2 O 4 materials belongs to the H+/Zn2+ co-embedding/de-embedding process. [ABSTRACT FROM AUTHOR]

In this paper, we prepared a new probe, a supramolecular compound composed of esculetin (ESC) and a cucurbit[8]uril (Q[8]). Ultraviolet, fluorescence and other methods have shown that ESC and Q[8] formed a 2 : 1 (ESC2@Q[8]) inclusion compound with weak fluorescence, which could efficiently identify metal aluminum ions in a pH = 5.0 water system, and emit strong indigo blue fluorescence to achieve naked eye recognition. In the competition experiment, this probe exhibited the specific recognition of aluminum ions. Furthermore, its recognition mechanism was explored through crystal diffraction and it was found that the carbonyl oxygens on the port of Q[8] and the hydroxyl oxygen atoms of ESC together formed a ternary complex with Al3+ ((ESC2@Q[8])@Al3+), which made the host–guest fluorescent probe form a hyper-conjugated system to achieve the effect of fluorescence enhancement. The fluorescence intensity had a good linear correlation with Al3+ concentration (R2 = 0.9838) in the range of 0.3–2.4 × 10−5 mol L−1. The detection limit was 9.39 × 10−9 mol L−1, which may have potential and application prospects for detecting metal ions in water systems. [ABSTRACT FROM AUTHOR]

Abstract: Methods to measure the sequence diversity of polymerase chain reaction (PCR)-amplified DNA lack standards for use as assay calibrators and controls. Here we present a general and economical method for developing customizable DNA standards of known sequence diversity. Standards ranging from 1 to 25,000 sequences were generated by directional ligation of oligonucleotide “words” of standard length and GC content and then amplified by PCR. The sequence accuracy and diversity of the library were validated using AmpliCot analysis (DNA hybridization kinetics) and Illumina sequencing. The library has the following features: (i) pools containing tens of thousands of sequences can be generated from the ligation of relatively few commercially synthesized short oligonucleotides; (ii) each sequence differs from all others in the library at a minimum of three nucleotide positions, permitting discrimination between different sequences by either sequencing or hybridization; (iii) all sequences have identical length, GC content, and melting temperature; (iv) the identity of each standard can be verified by restriction digestion; and (v) once made, the ends of the library may be cleaved and replaced with sequences to match any PCR primer pair. These standards should greatly improve the accuracy and reproducibility of sequence diversity measurements. [Copyright &y& Elsevier]

• We analyzed clinical characteristics of four individuals with propionic acidemia. • Through whole-exome sequencing and SNP-array, five PCCB variants were identified. • Preimplantation genetic testing guided the successful embryo transfer and implantation. Propionic acidemia (PA) is an autosomal recessive metabolic disorder caused by a deficiency of propionyl-CoA carboxylase and mutations in the PCCA and PCCB genes. In this study, we investigated the clinical characteristics of individuals with PA and conducted genetic analyses to provide new genetic evidence for the diagnosis of PA. We conducted whole-exome sequencing and Sanger sequencing in four individuals with PA from three unrelated Chinese families. We also performed a structural analysis of the PCCB protein variants. Couples from the three families included in our study underwent in vitro fertilization with preimplantation genetic testing. We found five variants of PCCB. These biallelic variants were inherited from heterozygous parental carriers and were located in the functional domain, absent in human population genome datasets, and predicted to be deleterious. These findings indicate that the variants might be responsible for the clinical features observed in these particular patients with PA. Through successful embryo transfer and implantation, one of the couples fortunately gave birth to a healthy child. Overall, our study can expand the mutation spectrum of PCCB and provide useful information for the prenatal diagnosis of PA and genetic counseling for affected individuals. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is the etiological agent responsible for the ongoing pandemic of coronavirus disease 2019 (COVID-19). The main protease of SARS-CoV-2, 3CLpro, is an attractive target for antiviral inhibitors due to its indispensable role in viral replication and gene expression of viral proteins. The search of compounds that can effectively inhibit the crucial activity of 3CLpro, which results to interference of the virus life cycle, is now widely pursued. Here, we report that epigallocatechin-3-gallate (EGCG), an active ingredient of Chinese herbal medicine (CHM), is a potent inhibitor of 3CLpro with half-maximum inhibitory concentration (IC50) of 0.874 ± 0.005 μM. In the study, we retrospectively analyzed the clinical data of 123 cases of COVID-19 patients, and found three effective Traditional Chinese Medicines (TCM) prescriptions. Multiple strategies were performed to screen potent inhibitors of SARS-CoV-2 3CLpro from the active ingredients of TCMs, including network pharmacology, molecular docking, surface plasmon resonance (SPR) binding assay and fluorescence resonance energy transfer (FRET)-based inhibition assay. The SPR assay showed good interaction between EGCG and 3CLpro with KD ~6.17 μM, suggesting a relatively high affinity of EGCG with SARS-CoV-2 3CLpro. Our results provide critical insights into the mechanism of action of EGCG as a potential therapeutic agent against COVID-19. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochemistry and surface-enhanced Raman spectroscopy to specifically recognize Chlorpyrifos by the aptamer. • Partial least squares model is introduced to solve the interference problem, and fully selective quantitative analysis is realized. • The aptamer-based sensor exhibited favorable selectivity and stability in spiked samples. Food safety is the focus and hot topic of the global population. Addressing pesticide residues is of great importance for environmental protection and sustainable development. Surface enhanced Raman spectroscopy (SERS), as a semi-quantitative technique, limits the accuracy of quantitative analysis. Therefore, a single analysis method can't satisfy the study of complex systems. The main goal of this study was to develop a biochemical sensor, SERS and electrochemical methods were used to prove the specific recognition of chlorpyrifos by an aptamer. The detection mechanism is discussed. The partial least squares (PLS) model is introduced in the spectral data analysis to solve the interference problems, so that the developed aptamer can achieve fully selective quantitative analysis. The developed sensor, combined with the PLS model, has high accuracy and precision in the detection of chlorpyrifos residues in real samples. The application of the PLS model to the spiked standard samples of apple and rice improves the recoveries in the range of 92.69% − 112.55% after the addition of the three interfering pesticides. The overall results show that the aptamer-based SERS combined with electrochemistry and the PLS model can be used to solve the problem of accurate quantification of anti-interference and achieve quality and safety. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the α-glucosidase inhibitory compounds of the herb lycopus (L.) lucidus turcz variant hirtus Regel. The study uses column chromatography in the isolation of compounds and mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy in their identification. The study shows a linear relationship of α-glucosidase inhibitory rates with the concentration.

Background: Prezygotic de novo mutations may be inherited from parents with germline mosaicism and are often overlooked when the resulting phenotype affects only one child. We aimed to identify paternal germline mosaicism in an index family and provide a strategy to determine germline mosaicism.' Methods: Whole‐exome sequencing was performed on an Alport syndrome‐affected child. Variants were validated using Sanger sequencing in the pedigree analysis. An apparent de novo mutation was tested by next‐generation sequencing (NGS) following chromosome microdissection of the mutant region (MicroSeq) to clarify its homologous chromosome source. Mosaic mutation in sperm samples was detected using targeted next‐generation sequencing (TNGS). Self‐prepared mosaic DNA samples of the 3% and 0.1% mutant fractions were used to evaluate the TNGS detection sensitivity. Results: Two novel heterozygous variants, maternally inherited c.1322delT (p.Ile441Thrfs*17) and the de novo mutation c.2939T>A (p.Leu980Ter), in the COL4A3 gene were discovered in the propositus. MicroSeq identified c.2939T>A in the paternal chromosome, which was in trans with c.1322delT. The frequency of c.2937A was 2.65% in the father's sperm sample. We also showed that a 500X depth coverage may detect a mosaic mutation with an allele frequency as low as 2%–3% using TNGS. Conclusion: MicroSeq is a valuable tool to identify the allele source of de novo mutations in a single patient. TNGS can be used to assess the mosaic ratios of known sites. We provided a systematic algorithm to detect germinal mosaicism in a single patient. This algorithm may have implications for genetic and reproductive counseling on germline mosaicism. [ABSTRACT FROM AUTHOR]

• One propionic acidemia case experienced next-generation sequencing three times. • Report two novel mutations of the PCCA gene, c.1746 G>C and exon3-4 deletion. • These compound heterozygous PCCA gene mutations cause propionic acidemia. • Present some limitations of whole-exome sequencing. • Emphasize the importance of clinical experience for genetic diagnosis. Propionic acidemia (PA) is an inborn metabolic error characterized by the accumulation of propionic acid due to deficiency of propionyl-CoA carboxylase (PCC). In this study, we present an intractable case with PCC activity defects. Although next-generation sequencing was applied twice to test genetic defects of the patients, no pathogenic mutations of a metabolic disease gene were identified. Mutations related to the disease were screened in prenatal diagnosis, but the mother still gave birth to an unhealthy neonate. We analyzed the second sequencing data and found that a novel synonymous PCCA mutation c.1746 G>C (p.S582S), which leads to an exon 19 skip, was screened out. Furthermore, a deletion mutation covering exon 3 and exon 4 of the PCCA gene was identified using q-PCR and DNA breakpoint test. Both of these can result in the loss of PCCA protein function. The finding expands the mutation spectrum of the PCCA gene and indicates that another technology such as cDNA analysis, multiplex ligation-dependent probe amplification (MLPA), or long-read whole-genome sequencing should be considered to improve the detection rates of special cases. [ABSTRACT FROM AUTHOR]

Severe asthenozoospermia is a common cause of male infertility. Recent studies have revealed that SPEF2 mutations lead to multiple morphological abnormalities of the sperm flagella (MMAF) without primary ciliary dyskinesia (PCD) symptoms in males, but PCD phenotype was also found in one female individual. Therefore, whether there is a phenotypic continuum ranging from infertile patients with PCD to MMAF patients with no or low noise PCD manifestations remains elusive. Here, we performed whole-exome sequencing in 47 patients with severe asthenozoospermia from 45 unrelated Chinese families. We identified four novel biallelic mutations in SPEF2 (8.9%, 4/45) in six affected individuals (12.8%, 6/47), while no deleterious biallelic variants in SPEF2 were detected in 637 controls, including 219 with oligoasthenospermia, 195 with non-obstructive azoospermia, and 223 fertile controls. Notably, all six patients exhibited PCD-like symptoms, including recurrent airway infections, bronchitis, and rhinosinusitis. Ultrastructural analysis revealed normal 9 + 2 axonemes of respiratory cilia but consistently abnormal 9 + 0 axoneme or disordered accessory structures of sperm flagella, indicating different roles of SPEF2 in sperm flagella and respiratory cilia. Subsequently, a Spef2 knockout mouse model was used to validate the PCD-like phenotype and male infertility, where the subfertility of female Spef2−/− mice was found unexpectedly. Overall, our data bridge the link between MMAF and PCD based on the association of SPEF2 mutations with both infertility and PCD in males and provide basis for further exploring the molecular mechanism of SPEF2 during spermiogenesis and ciliogenesis. [ABSTRACT FROM AUTHOR]

• Cucurbit[7]uril was the host, trimethoprim is the object. • The interaction was investigated by 1H NMR, MS, ITC and other methods. • The inclusion compound with the molar interaction ratio of 1:1 was formed. • After interaction, the water solubility of the trimethoprim was improved. Trimethoprim (TMP) is a broad-spectrum antibacterial agent that exhibits an obvious synergistic effect when used in combination with sulfa antibiotics, but its poor solubility and other drawbacks limit its applications. Herein, the interaction between TMP and cucurbit[7]uril (Q[7]), and the effect of Q[7] on the properties of TMP were investigated using UV-vis and fluorescence spectroscopy, isothermal titration calorimetry (ITC), 1H NMR spectroscopy and mass spectrometry. The results showed that TMP and Q[7] interacted to form a 1:1 inclusion complex (TMP@Q[7]). After interacting with TMP, Q[7] increased the solubility of TMP in an aqueous solution by 7.75-fold, effectively prolonging the release time of TMP in artificial gastroenteric juice, and plays a role in its sustained release. However, the stability and antibacterial activity of TMP in artificial gastroenteric juice were not affected. [ABSTRACT FROM AUTHOR]

In this study, a method for the determination of pepsin using a 3-hydroxyflavone (3-HF)-bovine serum albumin (BSA) complex as a fluorescent probe was established. Under acidic conditions, 3-HF can react with BSA to emit strong green fluorescence, which involves an excited state intramolecular proton transfer and fluorescence resonance energy transfer. After pepsin is added, the fluorescence of the 3-HF-BSA system is quenched due to the hydrolysis of BSA. The degree of 3-HF-BSA fluorescence quenching has a good linear relationship with the concentration of pepsin in the range of 10–80 μg/mL. The correlation coefficient was R 2 = 0.9932 and the detection limit was 2.41 μg/mL. This method has high selectivity and good stability and has been used to determine pepsin in real samples with satisfactory results. [Display omitted] • 3-Hydroxyflavone (3-HF) can react with bovine serum albumin (BSA) to emit strong green fluorescence. • Pepsin can significantly quench the fluorescence of 3-HF-BSA. • 3-HF-BSA can be used as fluorescent probe to detect pepsin. • The linear equation was y = − 4.8962 x + 746.1861 , the correlation coefficient was R 2 = 0.9932, and the LOD was 2.41 μg/mL. [ABSTRACT FROM AUTHOR]

ABSTRACT: Aptamers are single-stranded DNA or RNA that can specifically bind to a target substance with high affinity. Pesticides have obvious biological effects and are very harmful to the human body and the environment. Surface-enhanced Raman spectroscopy (SERS) can be combined with aptamer for the rapid detection of pesticide residues because of its simple operation and high sensitivity. However, a single analysis method has certain limitations and can't satisfy the research of complex system. In this study, SERS and electrochemical were used to prove the specific recognition of malathion by aptamer. The biochemical sensor directly detected the SERS spectra of the aptamer, malathion, and aptamer-malathion through the SERS method. Malathion could also be verified the specific recognition of aptamer by differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Based on the peak difference before and after the combination of malathion and aptamer, a detection method for the specific recognition of malathion in a complex system was established. The identification mechanism was discussed. Then, the practical detection of malathion demonstrated the practicability of the method. The method was applied for the detection of malathion in spiked apple and bell pepper samples. The recoveries were in the range of 89.80%–106.50%, and the relative standard deviations were from 2.51%–6.92%. The use of aptamers for the specific detection of pesticides will have the potential for broad applications in the future. • Electrochemistry and surface-enhanced Raman spectroscopy were combined to specifically recognize malathion by the aptamer. • induce silver nanoparticles to form Calcium ions were used as aggregating agents to induce silver nanoparticles to form "hot spots". • A method for the detection of practical complex samples was established. • The aptamer-based sensor exhibited favorable selectivity, reliability, and stability in spiked samples. [ABSTRACT FROM AUTHOR]

The powder-in-tube method is widely used in fabricating iron-based superconducting wires and tapes. To make tapes, a multi-pass rolling process is usually adopted. However, the multi-pass rolling process limits the efficiency of tapes. In this work, rolling deformation technique was studied systematically by fabricating Sr 1 − x K x Fe 2 As 2 superconducting tapes. The total rolling reduction ratio is about 80% and the difference of superconducting performance of tapes rolled by 2, 3, 5 and 7 passes has been investigated. The critical current density J c , Vickers micro-hardness and microstructure of the superconducting core indicate that tapes after 2, 3, 5 and 7 rolling passes exhibit a similar trend. The width of the tapes and the area of superconducting cores increase with decreasing the number of rolling passes, but the transport J c of tapes after different rolling passes seems to be the same, except for the tape rolled by 2 passes, whose transport J c is lower than the other tapes. Concerning the geometry uniformity for the superconducting cores, the sausaging phenomenon was not observed from the photograph of longitudinal cross-section of all the samples. “Lobes” phenomenon on transverse cross-section can be suppressed through decreasing the rolling passes. Therefore, we can obtain uniform and high-performance Ag-sheathed iron-based superconducting tapes by cutting the number of rolling passes down to 3, which is more advantageous to the large-scale producing in the future. [ABSTRACT FROM AUTHOR]

Zn-, In- and Pb-added Ag-sheathed Sr 1 − x K x Fe 2 As 2 tapes were fabricated through the powder-in-tube method. All added tapes are found to have increased transport J c at 4.2 K in fields up to 14 T than the pure samples. The best J c result has been achieved in Zn-added tapes. Microstructure investigations reveal that Zn addition can improve both phase uniformity and grain connectivity of Sr 1 − x K x Fe 2 As 2 , thus resulting in higher J c . Furthermore, the critical temperature for the added tapes decreased very slightly (only about 0.4 K). The role of Zn addition may be beneficial in promoting a large range of applications for iron-pnictide conductors. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method for synthesis of hybrid thiohemicucurbiturils has been efficiently developed. • Some carbonyl groups at the portal position of hemicucurbituril are replaced by thiono group. • Contrary to the acid condition for synthesis of traditional hemicucurbiturls, this method provides a moderate condition without acid and base. • This method provides a potential platform for modular synthesis of novel hybrid hemicucurbiturl derivatives with various motifs. A method for synthesis of hybrid thiohemicucurbiturils has been developed. With this method, three novel thiohemicucurbiturils have been constructed. Contrary to the acid condition for synthesis of traditional hemicucurbiturls, this method provides a moderate condition which is compatible for more complicated structure in synthesis of novel hybrid hemicucurbiturils. [ABSTRACT FROM AUTHOR]

Pnictide superconductors will be very promising for applications if wires with high critical current density Jc can allow reel-to-reel large-scale fabrication at low costs. To understand the mechanism(s) that limited Jc in flat-rolled \Sr0.6\K0.4\Fe2\As2 (Sr122) tapes, microstructure analysis has been considered the most direct and efficient way. Here, we report on high-resolution microstructure imaging and analysis on Fe-sheathed flat-rolled Sr122 tapes, which have a Jc as high as 2.3\times 10^4\ \A/cm^2 at 10 T and 4.2 K. The overlapping nature of the Sr122 plates was clearly observed. Transmission electron microscopy/scanning transmission electron microscopy analysis showed that, besides the cracks formed during the fabrication process, the \SrO2 phase and cavities caused by the inhomogeneously dispersed Sr and K are the other important factors suppressing Jc. The wetting phase FeAs at the grain boundaries can be partially substituted by Sn in Sn-added samples. Our findings provide insights that pave the way to further enhance the critical current of the rolled 122 tapes up to the practical level. [ABSTRACT FROM PUBLISHER]

Ag-sheathed Ba 0.6 K 0.4 Fe 2 As 2 superconducting tapes were fabricated by a scalable rolling process with high quality precursor. At 4.2 K and 10 T, the critical current density J c is 5.4 × 10 4 A cm −2 . We ascribe the excellent performance to the high purity and homogeneity of the superconducting phase, and the high density and high c -axis texture of the superconducting core. Our method provides a simple way to scale up the production of long-length iron-based superconducting tapes with high J c . [ABSTRACT FROM AUTHOR]

Graphene is a special form of carbon which can effectively enhance the critical current density J of MgB. In this work, a systematic investigation on the impact of sintering conditions and doping level was carried out for graphene-doped MgB tapes. It is found that an appropriate addition level, i.e., 8 at% in this work, is very critical to obtain a high J in graphene-doped samples. The critical field and pinning force are improved obviously due to the graphene doping. The magnetic J of samples sintered at 800 °C with 8 at% graphene doping reached 1.78 × 10 A/cm, at 5 T, 20 K. At the same time, the transport J was up to 2.38 × 10 A/cm at 10 T, 4.2 K. The lattice distortion caused by C substitution and residual C at the grain boundaries were thought to be the major factors affecting the J of graphene-doped MgB samples. [ABSTRACT FROM AUTHOR]

Using the magneto-optical imaging (MOI) technique, the intergranular critical current density Jc at various temperatures and the homogeneity of the local structure of the superconducting cores for the powder-in-tube (PIT) Sr1−xKxFe2As2 and SmFeAsO1−xFx tapes are systemically investigated. These two tapes have large transport Jc over 104 A cm−2 in self-field at 20 K and 4.2 K, respectively, but the Jc of the SmFeAsO1−xFx tape decreases rapidly with increasing magnetic field. The MOI characterization indicates large bulk currents circulating through the whole sample for both Sr1−xKxFe2As2 and SmFeAsO1−xFx tapes, but also reveals the inhomogeneity inside the SmFeAsO1−xFx sample. The results obtained from the MO measurements can be confirmed by the magnetic hysteresis measurements M(H) and the SEM examination. The weak high-field performance of the SmFeAsO1−xFx tape may be ascribed to its short-time heat treatment. [ABSTRACT FROM AUTHOR]

Highlights: [•] A systematic study on the effects of sintering temperature and Sn addition. [•] Field independence of Jc for the samples sintered at 850°C is optimal. [•] High transport Jc values have been achieved in all Sn-added tapes. [•] Sn addition involves in the Sr-122 phase formation and affects its composition. [•] Jc improvement is related to well connected grains, growth steps and dislocations. [ABSTRACT FROM AUTHOR]

• Uniform composition Cu 2 Se films on Si (111) prepared using pulsed laser deposition. • The exposed plane of Cu 2 Se is (111) c and parallel to Si surface. • Small effect of deposition time on the films' composition and microstructure. In this study, the low-temperature phase α-Cu 2 Se target with nearly ideal chemical stoichiometric ratio was synthesized through solid reaction process. After that, a series of pure and oriented α-Cu 2 Se films on single crystal Si (111) was prepared using pulsed laser deposition method, by carefully choosing the appropriate experimental parameters. Despite the increase of deposition time, the chemical composition, the crystal microstructure and the orientation of α-Cu 2 Se films keep the same. X-ray diffraction (XRD) and energy dispersive X-ray spectrometer show that all the α-Cu 2 Se films have the uniformity of chemical composition, without any other impurities. Scanning electron spectroscopy and high resolution transmission electron microscopy reveal that α-Cu 2 Se are stacked nanosheets with exposed crystal planes (111) c. Particularly, the (111) c planes are parallel to Si substrate surface proved by the results of XRD φ-scan and pole figure. This report is a further step to realize the adjustment of anisotropy of Cu 2 Se properties. [ABSTRACT FROM AUTHOR]

Highlights: [•] We fabricated Sr122+Ag tapes by intermediate sintering process of precursors. [•] Well textured tapes are achieved by a simple rolling process. [•] The resulting samples possess dense and homogeneous microstructure. [•] Transport Jc are the highest values for the iron- pnitides with Ag addition. [Copyright &y& Elsevier]