A saturated genetic linkage map of autotetraploid alfalfa (Medicago sativa L.) developed using genotyping-by-sequencing is highly syntenous with the Medicago truncatula genome.

A genetic linkage map is a valuable tool for quantitative trait locus mapping, map-based gene cloning, comparative mapping, and whole-genome assembly. Alfalfa, one of the most important forage crops in the world, is autotetraploid, allogamous, and highly heterozygous, characteristics that have impeded the construction of a high-density linkage map using traditional genetic marker systems. Using genotyping-by-sequencing (GBS), we constructed low-cost, reasonably high-density linkage maps for both maternal and paternal parental genomes of an autotetraploid alfalfa F1 population. The resulting maps contain 3591 single-nucleotide polymorphism markers on 64 linkage groups across both parents, with an average density of one marker per 1.5 and 1.0 cM for the maternal and paternal haplotype maps, respectively. Chromosome assignments were made based on homology of markers to the M. truncatula genome. Four linkage groups representing the four haplotypes of each alfalfa chromosome were assigned to each of the eight Medicago chromosomes in both the maternal and paternal parents. The alfalfa linkage groups were highly syntenous with M. truncatula, and clearly identified the known translocation between Chromosomes 4 and 8. In addition, a small inversion on Chromosome 1 was identified between M. truncatula and M. sativa. GBS enabled us to develop a saturated linkage map for alfalfa that greatly improved genome coverage relative to previous maps and that will facilitate investigation of genome structure. GBS could be used in breeding populations to accelerate molecular breeding in alfalfa

Neutron powder diffraction study on the iron-based nitride superconductor ThFeAsN

We report neutron diffraction and transport results on the newly discovered superconducting nitride ThFeAsN with $T_c=$ 30 K. No magnetic transition, but a weak structural distortion around 160 K, is observed cooling from 300 K to 6 K. Analysis on the resistivity, Hall transport and crystal structure suggests this material behaves as an electron optimally doped pnictide superconductors due to extra electrons from nitrogen deficiency or oxygen occupancy at the nitrogen site, which together with the low arsenic height may enhance the electron itinerancy and reduce the electron correlations, thus suppress the static magnetic order.Comment: 4 pages, 4 figures, Accepted by EP

A Mott insulator continuously connected to iron pnictide superconductors

Iron-based superconductivity develops near an antiferromagnetic order and out of a bad metal normal state, which has been interpreted as originating from a proximate Mott transition. Whether an actual Mott insulator can be realized in the phase diagram of the iron pnictides remains an open question. Here we use transport, transmission electron microscopy, X-ray absorption spectroscopy, and neutron scattering to demonstrate that NaFe$_{1-x}$Cu$_x$As near $x\approx 0.5$ exhibits real space Fe and Cu ordering, and are antiferromagnetic insulators with the insulating behavior persisting above the N\'eel temperature, indicative of a Mott insulator. Upon decreasing $x$ from $0.5$, the antiferromagnetic ordered moment continuously decreases, yielding to superconductivity around $x=0.05$. Our discovery of a Mott insulating state in NaFe$_{1-x}$Cu$_x$As thus makes it the only known Fe-based material in which superconductivity can be smoothly connected to the Mott insulating state, highlighting the important role of electron correlations in the high-$T_{\rm c}$ superconductivity.Comment: in press, Nat. Commun., 4 figures, supplementary information available upon reques

Моделирование и оптимизация технологического процесса и средств механизации производства зерна для среднего Китая на базе белорусской техники

One of the main problems in grain production in China is the high level of unit costs (high cost price). The main reason is the low level of mechanization. Development of efficient technologies and means of mechanization is a promising area allowing to decrease the level of unit costs at a given labor efficiency and maintaining the achieved yield. Grain production is a complex system associated with a large amount of information: agro-technological (crop variety, crop yield, physical-and-mechanical parameters of land plots, terms of operations, permissible speed range for specific operations, etc.), technical-and-economic (power and traction parameters, throughput, working width, operating weight, hopper volume , cost). At present, efficient methods for studying complex systems have appeared as a result of development and widespread implementation of computer mathematics systems, which allow us to study mechanization technologies and tools using multi-factor modeling and multi-criteria optimization. The paper presents a multi-factor mathematical model, peculiar for the fact that the three groups of simultaneously varying factors are taken for the first time engine power, MTA speed, timing of the main energy-intensive operations – plowing, harvesting, and as conflicting optimization parameters unit cost level, coefficient of crop losses, labor efficiency, which allowed a comprehensive study of the grain production process in any natural-production conditions. A technological process has been developed (units speed and timing of the main operations (plowing, harvesting) and the corresponding range of machines and equipment, ensuring minimum level of unit costs at a given labor efficiency and maintaining the achieved crop yield, taking into account the specifics of the Middle China (2 crops per year).Одной из главных проблем при производстве зерна в Китае является высокий уровень удельных затрат (высокая себестоимость). Основная причина – низкий уровень механизации. Разработка эффективных технологий и средств механизации является перспективным направлением, позволяющим снизить уровень удельных затрат при заданной производительности труда и сохранении достигнутой урожайности. Производство зерна является сложной системой, связанной с большим объемом информации: агротехнологической (сорт культуры, урожайность, физико-механические параметры участков, сроки выполнения операций, допустимый интервал скоростей для конкретной операции и т.д.), технико-экономической (мощностные и тяговые характеристики, пропускная способность, ширина захвата, эксплуатационная масса, объем бункера, стоимость). В настоящее время появились эффективные методы изучения сложных систем в результате разработки и широкого внедрения систем компьютерной математики, которые позволяют исследовать технологии и средства механизации методом многофакторного моделирования и многокритериальной оптимизации. В статье представлена многофакторная математическая модель, отличающаяся тем, что впервые взяты три группы одновременно варьируемых факторов – мощность двигателей, скорость движения МТА, сроки выполнения основных энергоемких операций – вспашка, уборка, а в качестве конфликтующих между собой параметров оптимизации – уровень удельных затрат, коэффициент потерь урожая, производительность труда, что позволяет всесторонне исследовать процесс производства зерна в любых природно-производственных условиях. Разработан технологический процесс (скорость движения агрегатов и сроки проведения основных операций (вспашка, уборка)) и соответствующий комплекс машин и оборудования, обеспечивающий минимальный уровень удельных затрат при заданной производительности труда и сохранении достигнутой урожайности с учетом специфики среднего Китая (2 урожая в год)

Identification of AaAtg8 as a marker of autophagy and a functional autophagy-related protein in Aedes albopictus

Aedes albopictus is a primary vector of hundreds of pathogens. Strong environmental adaptability and extensive global distribution of Aedes albopictus make it a severe threat to human health. Autophagy is a cellular process involved in maintenance of cellular homeostasis and recirculation of cytoplasm to generate macromolecule constituents and energy under different stress conditions. Many autophagy-related (Atg) proteins have been identified in yeast and were found in various organisms subsequently, indicating that the basic mechanism of autophagy is well conserved in eukaryotes. Among all Atg proteins, Atg8 plays important roles in autophagy and is widely used as a marker to monitor autophagic activity in yeast, Drosophila, nematodes, zebrafish and mammals. By now, Atg proteins in Aedes albopictus have not been reported yet and the autophagy pathway in Aedes albopictus remains unclear. This study identified a homolog of Atg8 from Aedes albopictus and named it AaAtg8. Sequence analysis revealed that AaAtg8 was highly conserved in the Atg8 family. This work proved that AaAtg8 was a functional Atg protein of Aedes albopictus and expressed during developmental and adult stages of Aedes albopictus. Moreover, the study also established the basic methods for autophagy study in C6/36 cells. First, it was proved that both rapamycin and starvation were applicable ways to induce autophagy in C6/36 cells, and that 3-methyladenine and chloroquine could be used to inhibit early and late stages of autophagy in C6/36 cells, respectively. Second, the results in this study showed that monodansylcadaverine staining could be used to detect autophagy in C6/36 cells. Additionally, the study revealed that the level of autophagy in C6/36 cells could be monitored by the turnover assay of AaAtg8 or fluorescent AaAtg8. Taken together, this study identified AaAtg8, the first reported Atg protein in Aedes albopictus. It also provided useful methods for studying autophagy in Aedes albopictus. To our knowledge, this is the first work about autophagy in Aedes albopictus

Shotgun metagenomic sequencing reveals skin microbial variability from different facial sites

Biogeography (body site) is known to be one of the main factors influencing the composition of the skin microbial community. However, site-associated microbial variability at a fine-scale level was not well-characterized since there was a lack of high-resolution recognition of facial microbiota across kingdoms by shotgun metagenomic sequencing. To investigate the explicit microbial variance in the human face, 822 shotgun metagenomic sequencing data from Han Chinese recently published by our group, in combination with 97 North American samples from NIH Human Microbiome Project (HMP), were reassessed. Metagenomic profiling of bacteria, fungi, and bacteriophages, as well as enriched function modules from three facial sites (forehead, cheek, and the back of the nose), was analyzed. The results revealed that skin microbial features were more alike in the forehead and cheek while varied from the back of the nose in terms of taxonomy and functionality. Analysis based on biogeographic theories suggested that neutral drift with niche selection from the host could possibly give rise to the variations. Of note, the abundance of porphyrin-producing species, i.e., Cutibacterium acnes, Cutibacterium avidum, Cutibacterium granulosum, and Cutibacterium namnetense, was all the highest in the back of the nose compared with the forehead/cheek, which was consistent with the highest porphyrin level on the nose in our population. Sequentially, the site-associated microbiome variance was confirmed in American populations; however, it was not entirely consistent. Furthermore, our data revealed correlation patterns between Propionibacterium acnes bacteriophages with genus Cutibacterium at different facial sites in both populations; however, C. acnes exhibited a distinct correlation with P. acnes bacteriophages in Americans/Chinese. Taken together, in this study, we explored the fine-scale facial site-associated changes in the skin microbiome and provided insight into the ecological processes underlying facial microbial variations

Low-bandgap nonfullerene acceptor based on thieno[3,2-b]indole core for highly efficient binary and ternary organic solar cells

A low-bandgap nonfullerene acceptor (NFA) TIT-2FIC based on thieno[3,2-b]indole-thiophenes core has been developed. Compared with the analogue NFAs DTC(4Ph)-4FIC and IT-4F, TIT-2FIC exhibited remarkably red-shifted absorption, and up-shifted HOMO energy level. In addition, TIT-2FIC showed interesting universal miscibility with the donors nonfluorinated PBDB-T and fluorinated PM6, therefore the corresponding organic solar cells achieved promising power conversion efficiencies (PCEs) of 11.80% and 13.00%, respectively, which are higher compared to the counterpart IT-4F based cells. Furthermore, the ternary PM6:TIT-2FIC:Y6 cell pronounced a high PCE of 17.22%, being significantly improved from that of 16.04% for the binary PM6:Y6 cell. Similar improvement in PCEs from 13.41% to 14.46% was also observed in the ternary PM6:TIT-2FIC:IT-4F cell with TIT-2FIC as the third component. These results indicated that TIT-2FIC is universally applicable as an acceptor with nonfluorinated or fluorinated polymer donor materials in both binary and ternary cells