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

Spin excitations and the Fermi surface of superconducting FeS

High-temperature superconductivity occurs near antiferromagnetic instabilities and nematic state. Debate remains on the origin of nematic order in FeSe and its relation with superconductivity. Here, we use transport, neutron scatter- ing and Fermi surface measurements to demonstrate that hydro-thermo grown superconducting FeS, an isostructure of FeSe, is a tetragonal paramagnet without nematic order and with a quasiparticle mass significantly reduced from that of FeSe. Only stripe-type spin excitation is observed up to 100 meV. No direct coupling between spin excitation and superconductivity in FeS is found, suggesting that FeS is less correlated and the nematic order in FeSe is due to competing checkerboard and stripe spin fluctuations.Comment: 11 pages, 4 page

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

Copy Number Variation of Immune-Related Genes and Their Association with Iodine in Adults with Autoimmune Thyroid Diseases

Background. Autoimmune thyroid diseases (AITD) are complex conditions that are caused by an interaction between genetic susceptibility and environmental triggers. Iodine is already known to be an environmental trigger for AITD, but genes associated with susceptibility need to be further assessed. Therefore, the aims of this study were to assess the association between copy number variations (CNVs) and AITD, to identify genes related with susceptibility to AITD, and to investigate the interaction between iodine status and CNVs in the occurrence of AITD. Methods. Blood samples from 15 patients with AITD and 15 controls were assessed by chromosome microarray to identify candidate genes. The copy number of candidate genes and urinary iodine level was determined in adults from areas of different iodine statuses including 158 patients and 181 controls. Results. The immune-related genes, SIRPB1 and TMEM91, were selected as candidate genes. The distribution of SIRPB1 CNV in AITD patients and controls was significantly different and was considered a risk factor for AITD. There was no significant association between urinary iodine level and candidate gene CNVs. Conclusion. SIRPB1 CNV and an excess of iodine were risk factors for AITD, but an association with the occurrence of AITD was not found

Glacial-interglacial evolution of seasonal cooling events documented by land-snail eggs from Chinese loess

The alternations of glacial and interglacial cycles are a classical feature of Quaternary climatic evolution and have been demonstrated to be closely related to seasonal insolation changes at high northern latitudes. Therefore, seasonal features may provide insights into glacial-interglacial cycles. However, mainly due to the lack of long time series of seasonally sensitive proxies, little is known about seasonal changes on the glacial-interglacial scale. The unhatched eggs preserved in sediments can serve as a proxy of seasonal cooling events (e.g., cold spells) since biological principles indicate that egg hatching is sensitive to temperature changes, and cooling-event-induced low temperatures during the reproductive season are unfavorable for eggs to hatch. Vertebrate eggs are well documented in the geological records, but they rarely provide continuous records through time. Here we present a high-resolution time series of land-snail eggs from the Chinese Loess Plateau, spanning the last three glacial-interglacial cycles. The results show that seasonal cooling events, indicated by peaks in egg abundance, are strong during glacial inceptions and climate cooling shifts of the marine isotope stages (MIS) 7e/7d, MIS 5e/5d, MIS 5c/5b and MIS 3/2. They tend not to occur during deglacials. They may result in low temperatures unfavorable for egg hatching during the reproductive season. Although several factors may be involved, seasonal cooling events in the Chinese Loess Plateau seem to be positively and more closely related to high-northernlatitude ice sheet growth. This finding may provide a new perspective for understanding glacialinterglacial evolution

Multiferroicity in doped hexagonal LuFeO3

The hexagonal phase of LuFeO3 is a rare example of a multiferroic material possessing a weak ferromagnetic moment, which is predicted to be switchable by an electric field. We stabilize this structure in bulk form though Mn and Sc doping, and determine the complete magnetic and crystallographic structures using neutron-scattering and magnetometry techniques. The ferroelectric P6(3)cm space group is found to be stable over a wide concentration range, ordering antiferromagnetically with Neel temperatures that smoothly increase following the ratio of c to a (c/a) lattice parameters up to 172 K, the highest found in this class of materials to date. The magnetic structure for a range of temperatures and dopings is consistent with recent studies of high quality epitaxial films of pure hexagonal LuFeO3 including a ferromagnetic moment parallel to the ferroelectric axis. We propose a mechanism by which room-temperature multiferroicity could be achieved in this class of materialsopen

Flat band magnetism and helical magnetic order in Ni-doped SrCo2_2As2_2

A series of Sr(Co$_{1-x}$Ni$_x$)$_2$As$_2$ single crystals was synthesized allowing a comprehensive phase diagram with respect to field, temperature, and chemical substitution to be established. Our neutron diffraction experiments revealed a helimagnetic order with magnetic moments ferromagnetically (FM) aligned in the $ab$ plane and a helimagnetic wavevector of $q=(0,0,0.56)$ for $x$ = 0.1. The combination of neutron diffraction and angle-resolved photoemission spectroscopy (ARPES) measurements show that the tuning of a flat band with $d_{x^2-y^2}$ orbital character drives the helimagnetism and indicates the possibility of a quantum order-by-disorder mechanism.Comment: 9 pages, 12 figures, Supplementary Material available upon request, accepted by Phys. Rev.

The impact of giant jellyfish Nemopilema nomurai blooms on plankton communities in a temperate marginal sea

Abstract(#br)This study focused on the bloom-developing process of the giant jellyfish, Nemopilema nomurai , on phytoplankton and microzooplankton communities. Two repeated field observations on the jellyfish bloom were conducted in June 2012 and 2014 in the southern Yellow Sea where blooms of N . nomurai were frequently observed. We demonstrated that the bloom was made up of two stages, namely the developing stage and the mature stage. Total chlorophyll a increased and the concentrations of inorganic nutrients decreased during the developing stage, while both concentrations maintained stable and at low levels during the mature stage. Our analysis revealed that phosphate excreted by growing N . nomurai promoted the growth of phytoplankton at the developing stage. At the mature stage, size compositions of microzooplankton were altered and tended to be smaller via a top-down process, while phytoplankton compositions, affected mainly through a bottom-up process, shifted to be less diatoms and cryptophytes but more dinoflagellates