Cultivar differences in the grain protein accumulation ability in rice (Oryza sativa L.)

AbstractThe demand for rice grain protein content (GPC) differs in different regions of the world. Despite large differences in GPC among cultivars, evaluation of the effects of genotype on GPC is difficult because GPC is influenced not only by cultivar traits (such as nitrogen uptake ability, sink size and heading date) but also by the environment. We hypothesized that grain protein accumulation ability (GPA) also affects GPC. The objective of this study was to clarify the differences in GPA among six lodging-tolerant, high-yielding Japanese cultivars: Bekoaoba, Habataki, Takanari, Hokuriku193, Momiroman, and Akenohoshi. To produce a wide variation in nitrogen availability per unit sink capacity (Nav), we used nitrogen topdressing at heading and spikelet-thinning treatment. In each cultivar, we found a logarithmic relation between GPC and Nav: GPC=A×Ln(Nav)+B, where A is the regression coefficient and B is a constant. A highly significant difference in regression coefficients among cultivars was found (P<0.01). The regression coefficient was considered to be a measure of GPA; it varied from 0.969 in Bekoaoba to 1.820 in Takanari. This relation suggests that GPC is determined by Nav and GPA and that the environment affects GPC through Nav. GPA is a good criterion for evaluation of the effects of genotype on GPC. Nitrogen harvest index was highly significantly explained by multiple regression with GPA and the ratio of sink capacity to total dry matter production as independent variables, suggesting the influence of GPA on plant nitrogen dynamics during the grain-filling period. Therefore, it would be useful to determine the cultivars’ GPA values for optimizing nitrogen management

Impact of sea-ice dynamics on the spatial distribution of diatom resting stages in sediments of the Pacific Arctic region

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 126(7), (2021): e2021JC017223, https://doi.org/10.1029/2021JC017223.The Pacific Arctic region is characterized by seasonal sea-ice, the spatial extent and duration of which varies considerably. In this region, diatoms are the dominant phytoplankton group during spring and summer. To facilitate survival during periods that are less favorable for growth, many diatom species produce resting stages that settle to the seafloor and can serve as a potential inoculum for subsequent blooms. Since diatom assemblage composition is closely related to sea-ice dynamics, detailed studies of biophysical interactions are fundamental to understanding the lower trophic levels of ecosystems in the Pacific Arctic. One way to explore this relationship is by comparing the distribution and abundance of diatom resting stages with patterns of sea-ice coverage. In this study, we quantified viable diatom resting stages in sediments collected during summer and autumn 2018 and explored their relationship to sea-ice extent during the previous winter and spring. Diatom assemblages were clearly dependent on the variable timing of the sea-ice retreat and accompanying light conditions. In areas where sea-ice retreated earlier, open-water species such as Chaetoceros spp. and Thalassiosira spp. were abundant. In contrast, proportional abundances of Attheya spp. and pennate diatom species that are commonly observed in sea-ice were higher in areas where diatoms experienced higher light levels and longer day length in/under the sea-ice. This study demonstrates that sea-ice dynamics are an important determinant of diatom species composition and distribution in the Pacific Arctic region.This work was conducted by the Arctic Challenge for Sustainability (ArCS) project, Arctic Challenge for Sustainability II (ArCSII) project and ArCS program for overseas visits by young researchers. In addition, this work was partly supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Number JP20J20410 and JP21H02263. We thank Anderson laboratory members for their support of our study at WHOI, and also thank Robert Pickart, Leah McRaven, and Jacqueline Grebmeier for their support and assistance on the Healy cruises. Funding for DA, EF, and MR was provided by the NOAA Arctic Research Program through the Cooperative Institute for the North Atlantic Region (CINAR Award NA14OAR4320158), by the NOAA ECOHAB Program (NA20NOS4780195) and by the National Science Foundation Office of Polar Programs (OPP-1823002). This is ECOHAB contribution number ECO986.2021-12-1

A dehydrated space-weathered skin cloaking the hydrated interior of Ryugu

Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (–OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss

Spatial changes in the summer diatom community of the northern Bering Sea in 2017 and 2018

In recent years, the northern Bering Sea has experienced changes in the timing of sea-ice retreat and in hydrographic conditions during the summer. The influence of these environmental changes on the diatom community has not been examined. In this study, we investigated the spatial changes in the diatom community of the northern Bering Sea during the summers of 2017 and 2018, and evaluated the effects of environmental variability on these communities. We found that the diatom cell density and diversity varied with water masses. A cluster analysis based on cell density revealed that the diatom communities were separated into four groups, and that the distributions of three of these groups were different spatially between 2017 and 2018. In the Bering Strait and the Chirikov Basin regions, the diatom communities differed between 2017 and 2018. In 2017, these diatom communities were dominated by cold-water species such as Chaetoceros gelidus and Chaetoceros spp. (subgenus Hyalochaetae), while in 2018, the community was dominated by cosmopolitan species such as Thalassionema nitzschioides and Chaetoceros spp. (subgenus Phaeoceros). NMDS and multiple regression analysis indicated that the timing of the sea-ice retreat was the most important contributor to the differences in the diatom community. In contrast, there was no year-to-year difference south of St. Lawrence Island, possibly because nutrients were depleted and phytoplankton types other than diatoms were dominant

The community composition of diatom resting stages in sediments of the northern Bering Sea in 2017 and 2018: the relationship to the interannual changes in the extent of the sea ice

In the Bering Sea shelf, annual changes in the sea ice extent are large. In this study, we compare the viable diatom resting stages in sediments during the summer of 2017 when the sea ice retreat was late and 2018 when the sea ice retreat was early. South of St. Lawrence Island, the germinating cell number was 10-100 times greater in 2018 than it was in 2017. The taxonomic composition also showed large annual differences: Fragilariopsis/Fossula spp., which are ice algae species, were abundant in 2017, but Thalassiosira spp. dominated in 2018. Satellite observations confirmed that sea ice diminished before the ice-edge bloom in 2018, but sea ice remained until the ice-edge bloom in 2017. This study shows that the community composition of viable diatom resting stages is largely affected by the timing of the sea ice retreat

Popular Health Information Centers : construction of a inicial theory

This study aims to build a theoretical framework that embase the proposal, creation and implementation of a People's Health Information Center in public libraries and third sector organizations in the communities with socioeconomic vulnerability in São Carlos (SP) and the region as a public communication channel of science among the population through the dissemination and popularization of scientific library collections and information services. This information unit is designed based on the existing literature theory about People's Documentation Centers. The focus of this work is the health information, specifically information on popular health and alternative medicine. Moreover, the epistemological stance advocated to guide the professional practice and librarian policy stance should act on in Popular Health Information Centres follows the ideological line of the Popular Education movement of Paulo Freire, as well as the concept of "organic intellectual" of Antonio Gramsci. Finally are listed some spaces and contexts considered favorable and suitable for the application and development of the proposal. It also points up some theories and methodologies that would be advisable to start a research work of information needs in community health to be met by the Centre.Não recebi financiamentoO presente trabalho se propõe a construir um referencial teórico que embase a proposta de criação e implantação de um Centro de Informação em Saúde Popular nas bibliotecas públicas e organizações do terceiro setor das comunidades em situação de vulnerabilidade socioeconômica na cidade de São Carlos (SP) e região, como um canal de comunicação pública da ciência junto à população, por meio da divulgação e popularização científica de seu acervo e serviços informacionais. Essa unidade de informação foi concebida tendo como base teórica o conceito já existente na literatura sobre os Centros de Documentação Popular. O foco desse trabalho é a informação em saúde, mais especificamente a informação em Saúde Popular e medicina alternativa. Além disso, a postura epistemológica defendida para balizar a prática profissional e orientação política do bibliotecário que deve atuar nos Centros de Informação em Saúde Popular segue a linha ideológica do movimento de Educação Popular de Paulo Freire, bem como o conceito de “Intelectual Orgânico” de Antonio Gramsci. Por fim, são indicados alguns espaços e contextos considerados ideais para a aplicação e desenvolvimento da proposta. Além disso, apontam-se também algumas teorias e metodologias que seriam recomendáveis para se iniciar um trabalho de investigação das necessidades informacionais em saúde da comunidade a ser atendida pelo Centro

Potency of an inactivated influenza vaccine prepared from A/duck/Mongolia/245/2015 (H10N3) against H10 influenza virus infection in a mouse model

The H10N8 influenza virus became a threat to public health when cases of fatal infections were identified in China in 2013 and 2014. Thus, genetic and antigenic characterization of H10 influenza viruses and development of an appropriate vaccine are essential to prepare for a future pandemic by H10 influenza viruses. However, current information regarding these properties of H10 influenza viruses circulating in birds is limited. In this study, genetic analysis of H10 influenza viruses revealed that the viruses recently circulating in wild birds in East Asia are genetically close to human H10N8 influenza viruses. Furthermore, the antigenicity of H10 influenza viruses was stable among the viruses circulating in birds. An inactivated vaccine was prepared from A/duck/Mongolia/245/2015 (H10N3), which is genetically and antigenically close to the human H10 influenza viruses. The vaccine induced sufficient neutralizing antibodies against homologous and heterologous viruses in mice. The inactivated vaccine induced protective immunity sufficient to reduce the impact of challenges with A/duck/Hokkaido/W87/2007 (H10N2), which is pathogenic strain in mice. This study demonstrates that the inactivated whole virus particle vaccine prepared from viruses isolated from wild birds would be useful against a future pandemic influenza by H10 influenza viruses

Photophysiological response of diatoms in surface sediments to light exposure : A laboratory experiment on a diatom community in sediments from the Chukchi Sea

Diatoms form dense blooms in the Pacific Arctic region from spring to summer, supporting the unique benthic-pelagic coupling ecosystems. Although the Arctic has a severe light-limited season from autumn to winter, diatoms can proliferate in spring when sufficient light becomes available for photosynthesis. One of the crucial strategies for diatoms to survive in unfavorable growing conditions is to form resting stages. Because of enhanced primary and export production in the Pacific Arctic shelves, many viable diatom resting stages can be detected in the surface sediments. However, little is known about the photophysiological response of viable diatom cells, including resting stages, in sediments to light availability. We conducted a laboratory experiment investigating the photophysiological capabilities of the diatom cells containing resting stages using surface sediments from the Chukchi Sea shelf. As a result, diatoms grew dramatically after light exposure, and Chaetoceros socialis complex highly contributed to the enhanced diatom abundance. Their photophysiological changes were also evident from the maximum quantum efficiency (F-v/F-m) of photochemistry in photosystem II, C-13-based photosynthetic-energy (PE) parameters, diadinoxanthin (DD)-diatoxanthin (DT) pool size, and the de-epoxidation state (DES) of DD. Even after the excess light exposure suppressed the photosynthetic activity in the microalgal cells, the diatoms recovered quickly, indicating the high photophysiological plasticity to dynamic light changes. Therefore, our results suggest that diatoms in surface sediments have a high seeding potential for blooms in the Pacific Arctic shelf region