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Transferring desired genes from wild species to cultivars through alien addition lines (AALs) has been shown to be an effective method for genetic improvement. Cucumis hystrix Chakr. (HH, 2n = 24) is a wild species of Cucumis that possesses many resistant genes. A synthetic allotetraploid species, C. hytivus (HHCC, 2n = 38), was obtained from the cross between cultivated cucumber, C. sativus (CC, 2n = 14), and C. hystrix followed by chromosome doubling. Cucumis sativus - C. hystrix AALs were developed by continuous backcrossing to the cultivated cucumbers. In this study, 10 different types of AALs (CC-H01, CC-H06, CC-H08, CC-H10, CC-H12, CC-H06+H09, CC-H06+H10, CC-H06+H12, CC-H08+H10, CC-H01+H06+H10) were identified based on the analysis of fluorescence in situ hybridization (FISH) and molecular markers specific to C. hystrix chromosomes. And the behavior of the alien chromosomes in three AALs (CC-H01, CC-H06+H10, CC-H01+H06+H10) at meiosis was investigated. The results showed that alien chromosomes paired with C. sativus chromosome in few pollen mother cells (PMCs). Further, disomic alien addition lines (DAALs) carrying a pair of C. hystrix chromosome H10 were screened from the selfed progenies of CC-H10. Chromosome pairing between genomes provides cytological evidence for the possible introgression of alien chromosome segments. The development of AALs could serve as a key step for exploiting and utilizing valuable genes from C. hystrix. Keywords: Cucumis hystrix Chakr., alien addition lines, FISH, molecular markers, chromosome pairing. Le transfert de genes d'interet d'une espece sauvage a des cultivars via des lignees d'addition (AAL) s'est averee une voie efficace en amelioration genetique. Le Cucumis hystrix Chakr. (HH, 2n = 24) est une espece sauvage de Cucumis et possede plusieurs genes de resistance. Un allotetraploide synthetique, C. hytivus (HHCC, 2n = 38), a ete obtenu en croisant le concombre cultive C. sativus (CC, 2n = 14) avec le C. hystrix et en doublant les chromosomes. Les lignees AAL C. sativus - C. hystrix ont ete developpees au terme de retrocroisements repetes avec le concombre cultive. Dans ce travail, 10 types d'AAL (CC-H01, CC-H06, CC-H08, CC-H10, CC-H12, CC-H06+H09, CC-H06+H10, CC-H06+H12, CC-H08+H10, CC-H01+H06-H10) ont ete identifiees au moyen de l'hybridation in situ en fluorescence (FISH) et de marqueurs moleculaires specifiques des chromosomes du C. hystrix. Le comportement a la meiose des chromosomes etrangers dans trois lignees AAL (CC-H01, CC-H06+H10, CC-H01+H06+H10) a ete examine. Les resultats ont montre que les chromosomes etrangers s'appariaient avec des chromosomes du C. sativus dans certains androsporocytes. De plus, des lignees d'addition disomiques (DAAL) portant une paire de chromosomes H10 du C. hystrix ont ete identifiees au sein des progenitures issues de l'auto-fecondation des lignees CC-H10. L'appariement chromosomique entre genomes fournit des evidences cytologiques de la possible introgression de segments chromosomiques etrangers. Le developpement de lignees AAL pourrait servir d'etape cle pour exploiter et utiliser des genes utiles en provenance du C. hystrix. [Traduit par la Redaction] Mots-cles : Cucumis hystrix Chakr., lignees d'addition, FISH, marqueurs moleculaires, appariement des chromosomes., Introduction The genus Cucumis contains more than 50 species distributed mainly in Asia, Africa, and Australia, including two cultivated species: cucumber (Cucumis sativus L., CC, 2n = 2x = 14) [...]

Manganese (Mn) oxides are promising cathode materials for rechargeable aqueous Zn‐ion batteries. However, the Mn dissolution in weakly acidic electrolytes always hinders the development of better aqueous Zn–Mn batteries. Herein, a hydroxylated manganese oxide cathode material (H‐MnO2) is fabricated using an electrochemical method for stable aqueous Zn–Mn batteries without relying on the Mn2+ electrolyte additives. The partial hydroxylation of the oxides leads to charge redistribution of the material, changing the reaction thermodynamics and kinetics. Theoretical simulation suggests that the hydroxylation of manganese oxide promotes both Zn2+ adsorption thermodynamics and diffusion kinetics on the surface of H‐MnO2 but weakens the interaction between H+ and the electrode. Therefore, Zn2+ ions can be more reactive with the hydroxylated manganese oxide than H+ ions. Experimental results show that the Zn2+ insertion mechanism dominates the charge storage process of H‐MnO2, and the H+‐induced Mn dissolution reaction is effectively alleviated. Importantly, H‐MnO2 exhibits good cycling stability with 95% capacity retention over 5000 cycles at the current density of 3.8 A g−1 in the ZnSO4 electrolyte, outperforming the state‐of‐the‐art aqueous Zn–Mn batteries, even those with Mn2+ electrolyte additives. The findings provide new insights for designing stable manganese oxide cathodes in aqueous Zn–Mn batteries. [ABSTRACT FROM AUTHOR]

In order to develop food or tobacco usable flavour precursors, compounds 2‐hydroxypropyl benzoate (3a), propane‐1,2‐diyl dibenzoate (4a), 2‐hydroxypropyl cinnamate (3b) and propane‐1,2‐diyl (2E,2′ E)‐bis(3‐hydroxypropyl cinnamate) (4b) were synthesized by transesterification propanediol with vinyl benzoate and vinyl cinnamate under the biological enzyme Novozym435. The structures of the propanediol esters were characterized using nuclear magnetic resonance (1H NMR, 13C NMR), infrared spectroscopy (IR) and high‐resolution mass spectrometry (HRMS). The hygroscopicity and moisture retention capacity of reconstituted tobacco shreds with the synthesized propanediol were explored by 100 h hygroscopic desorption assay, model validation and low‐field nuclear magnetic resonance imaging (LF‐NMR). The results showed that the bound water content of 3a and 3b was lower than that of propanediol and higher than that of the control under both low (RH = 32%) and high (RH = 84%) humidity conditions. In addition, pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS) technique was applied to investigate the thermal behaviour of 3a and 3b. Four and five pyrolysis products were formed by pyrolysis of 3a and 3b, respectively. The main pyrolysis products benzoic acid and cinnamic acid could be used as flavouring agents in food and tobacco. 3a and 3b had good moisture and humidity retention effects as well as uniform and sustained flavour release. The results of the study not only effectively improve the water absorbency of reconstituted tobacco and enhance the flavour, which is suitable for the storage and smoking process, but also provide a reference for the further development of new flavour moisturizers in the tobacco industry. [ABSTRACT FROM AUTHOR]

Aqueous batteries with high safety and cost efficiency usually employ metallic cations as charge carriers. Recently, ammonium (NH4+) ion batteries using the nonmetal NH4+ as a charge carrier exhibit distinct electrochemical features from conventional aqueous batteries. Herein, the electrochemical performances of a bimetallic hydroxide material are systematically studied with different charge carriers in the electrolytes, including NH4+, as well as the conventional monovalent metallic cations K+ and Na+, respectively. Electrochemical results indicate that the charge storage process using NH4+ as the working ions exhibits a higher discharge plateau, smaller electrochemical polarization, and larger discharge capacity than that using conventional metallic charge carriers. Experimental characterizations and theoretical calculations suggest that the strong interaction between NH4+ and the electrode material, as well as the low NH4+‐ion diffusion barrier lead to these superior electrochemical features. The assembled NH4+‐ion battery exhibits a good energy density of 123 Wh kg(cathode+anode)−1 at the power density of 480 W kg(cathode+anode)−1. These fundamental findings are important for developing good safety, low‐cost, and high‐energy aqueous batteries with sustainable NH4+ charge carriers. [ABSTRACT FROM AUTHOR]

An angle sensitive transmission metasurface unit structure is designed in this paper. The metasurface unit presents a good transmission performance for the TE wave incidence, and has a linear phase response with the maximum phase difference up to 180° when the incidence angle changes in the range of −45° and +45°. Moreover, a reconfigurable design of the metasurface unit is realized by loading a varator, and the phase difference is extended to 270° to satisfy the demand of multibit metasurface. Based on the characteristics of angle sensitivity and reconfigurability of the metasurface unit, combined with the control of the varactor and the unit tilt angle, a new 1‐bit digital coding angle sensitive metasurface is proposed. The metasurface has a specification of 20 × 20 and a center frequency of 10 GHz. Both the simulation and measurement show that different transmission is realized for incident waves at different incident angles. It can form different beams, which can be used for multibeam modulation with the same frequency and same polarization. [ABSTRACT FROM AUTHOR]

The 10m chord versine is commonly used as the standard to evaluate track irregularity in medium and low speed maglev (MLSM). However, the amplitude frequency of the mid-chord offset method suffers distortion, which is more serious in the short waveform range, and the 10m chord versine will lose a lot of short waveform signals. Therefore, 10m chord versine cannot be used in engineering practice as the true track irregularity. To solve this problem, the method of numerical simulation is used to simulate the process mid-chord offset method. By comparing the errors of 10m chord versine in time domain and frequency domain, the exactness of the "deduced from small to large" algorithm is verified, and two inverse algorithms of "deduced from small to large" are established to obtain the chord versine of small chord length, expand the effective detection range of short waveform irregularity, and the method of "inverse filtering" is used to inverse the short waveform irregularity. The results show that the two inverse algorithms of "deduced from small to large" can well deduce the chord versine of small chord length, and the minimum chord length that can be deduced is twice the step length. Therefore, in order to expand the measurement range of short waveform, the sampling step length should be reduced as much as possible. Compared with model B, model A has a larger error due to the addition of boundary conditions, some outliers appear, step signals appear in the power spectral density, and the absolute error is within 0.025 mm. Model B has high accuracy and good transfer characteristics, and the absolute error can be controlled within 0.001 5 mm. The field measurement of 10m chord versine of F-shaped track of Changsha Maglev Express Line shows that the track irregularities in the wavelength range of 0.5~100 m can be effectively inverted with both models. [ABSTRACT FROM AUTHOR]