Variation in the diatom community under fast ice near Syowa Station, Antarctica, during the austral summer of 1997/98

Variations in abundance and community structure of diatoms under the fast ice near Syowa Station were investigated almost daily during the austral summer of 1997/98. Two periods of high chlorophyll a concentration were observed throughout the study : from the end of December to early January and from the middle to the end of January. Size fractionation of chlorophyll a revealed that phytoplankton during the former period consisted mostly of organisms larger than 20μm and during the latter period, 10-20μm. The large diatoms, Porosira pseudodenticulata and Pseudonitzschia turgiduloides, and small diatoms, Fragilariopsis spp., were the dominant organisms in the former and latter periods, respectively. Melting of the fast ice occurred in January, indicating a possibility that small sized diatoms were released from the ice to the water column. Accumulation of small diatoms in a sediment trap followed a decrease of their abundance in the water column. These results indicate that most of the ice algae detached from the ice sank directly to the bottom during the latter half of the austral summer

Reaction dynamics analysis of an E. coli protein translation system by computational modeling

A single enzymatic reaction can often be described by Michaelis-Menten kinetics, but once reactions are connected to one other, it becomes difficult to understand and capture a complete description of the reaction dynamics due to its high dimensionality. To elucidate the dynamic features of a biologically relevant large-scale reaction network, we constructed a computational model of minimal protein synthesis consisting of 241 components and 968 reactions that synthesize the Met-Gly-Gly (MGG) peptide based on an Escherichia coli-based reconstituted in vitro translation (IVT) system [1]. We performed a simulation using parameters collected primarily from the literature and found that the rate of MGG peptide synthesis becomes nearly constant in minutes, thus achieving a steady-state similar to experimental observations. In addition, concentration changes to 70% of the components, including intermediates, reached a plateau in a few minutes. However, the concentration change of each component exhibits several temporal plateaus, or a quasi-stationary state (QSS), before reaching the final plateau. To understand the complex dynamics, we focused on whether the components reached a QSS, mapped the arrangement of components in a QSS in the entire reaction network structure and investigated time-dependent changes. We found that components in a QSS form clusters that grow over time but not in a linear fashion and that this process involves the collapse and regrowth of clusters before the formation of a final large single cluster. These observations might commonly occur in other large-scale biological reaction networks. This developed analysis might be useful for understanding large-scale enzymatic reactions, thereby extracting the characteristics of the reaction network, including phase transitions. As the reconstituted IVT has been used for various applications inducing directed evolution of membrane proteins [2,3], the developed computational model might be useful in further enhancement of the yield of synthesized proteins using the reconstituted IVT. Please click Additional Files below to see the full abstract

Vibration Suppression of a Journal Bearing Using Temperature Control:A Preliminary Experiment

A prototype of a circular hydrodynamic journal bearing to control temperature distributions of the bearing bush and the oil film was manufactured, with a preliminary experiment subsequently conducted to evaluate the extent of vibration suppression within the bearing. The specifications of the bearing were as follows: a bearing diameter of 50 mm, a bearing length of 50 mm, and a radial clearance of 0.025 mm. The bearing bush was divided into six parts, and five Peltier devices were installed for cooling and heating each part. The parameters of the experiment were as follows: a load up to 100 N, a rotational speed up to 35 rps, and a lubricating oil of ISO VG22. When the lower half of the bearing bush was cooled and the upper half was heated, the vibration was suppressed under a specific operating condition.特集 : The Papers Presented at the Symposium on Mechanical Engineering, Industrial Engineering, and Robotics 2015 (MIER2015) held at Muroran, Hokkaido, Japan on 29 - 30 May 201

Effect of Dynamical SU(2) Gluons to the Gap Equation of Nambu--Jona-Lasinio Model in Constant Background Magnetic Field

In order to estimate the effect of dynamical gluons to chiral condensate, the gap equation of SU(2) gauged Nambu--Jona-Lasinio model, under a constant background magnetic field, is investigated up to the two-loop order in 2+1 and 3+1 dimensions. We set up a general formulation allowing both cases of electric as well as magnetic background field. We rely on the proper time method to maintain gauge invariance. In 3+1 dimensions chiral symmetry breaking ($\chi$SB) is enhanced by gluons even in zero background magnetic field and becomes much striking as the background field grows larger. In 2+1 dimensions gluons also enhance $\chi$SB but whose dependence on the background field is not simple: dynamical mass is not a monotone function of background field for a fixed four-fermi coupling.Comment: 20 pages, 5 figure

Evaluation of anti-stress nutrients in the endothelial cells with fluorescence indicator

Oxidative stress has emerged as an important pathogenic factor in the development of long-term complications, such as hypertension, atherosclerosis, nephropathy, and cancer. Taking many antioxidants from natural food may be effective to prevent us from those diseases. We have attempted to evaluate the effect of improvement by dietary antioxidants on the endothelial dysfunction induced by hyperglycemia. Fluorescence indicators for reactive oxygen species and nitric oxide were employed to the evaluation. The combination of those fluorescence indicators could be powerful tool to evaluate the effect of anti-stress nutrients on both oxidative stress and endothelial dysfunction

Population health and regional variations of disease burden in Japan, 1990–2015:a systematic subnational analysis for the Global Burden of Disease Study 2015

BackgroundJapan has entered the era of super-ageing and advanced health transition, which is increasingly putting pressure on the sustainability of its health system. The level and pace of this health transition might vary across regions within Japan and concern is growing about increasing regional variations in disease burden. The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015) provides a comprehensive, comparable framework. We used data from GBD 2015 with the aim to quantify the burden of disease and injuries, and to attribute risk factors in Japan at a subnational, prefecture-level.MethodsWe used data from GBD 2015 for 315 causes and 79 risk factors of death, disease, and injury incidence and prevalence to measure the burden of diseases and injuries in Japan and in the 47 Japanese prefectures from 1990 to 2015. We extracted data from GBD 2015 to assess mortality, causes of death, years of life lost (YLLs), years lived with disability (YLDs), disability-adjusted life-years (DALYs), life expectancy, and healthy life expectancy (HALE) in Japan and its 47 prefectures. We split extracted data by prefecture and applied GBD methods to generate estimates of burden, and attributable burden due to known risk factors. We examined the prefecture-level relationships of common health system inputs (eg, health expenditure and workforces) to the GBD outputs in 2015 to address underlying determinants of regional health variations.FindingsLife expectancy at birth in Japan increased by 4·2 years from 79·0 years (95% uncertainty interval [UI] 79·0 to 79·0) to 83·2 years (83·1 to 83·2) between 1990 and 2015. However, the gaps between prefectures with the lowest and highest life expectancies and HALE have widened, from 2·5 to 3·1 years and from 2·3 to 2·7 years, respectively, from 1990 to 2015. Although overall age-standardised death rates decreased by 29·0% (28·7 to 29·3) from 1990 to 2015, the rates of mortality decline in this period substantially varied across the prefectures, ranging from -32·4% (-34·8 to -30·0) to -22·0% (-20·4 to -20·1). During the same time period, the rate of age-standardised DALYs was reduced overall by 19·8% (17·9 to 22·0). The reduction in rates of age-standardised YLDs was very small by 3·5% (2·6 to 4·3). The pace of reduction in mortality and DALYs in many leading causes has largely levelled off since 2005. Known risk factors accounted for 34·5% (32·4 to 36·9) of DALYs; the two leading behavioural risk factors were unhealthy diets and tobacco smoking in 2015. The common health system inputs were not associated with age-standardised death and DALY rates in 2015.InterpretationJapan has been successful overall in reducing mortality and disability from most major diseases. However, progress has slowed down and health variations between prefectures is growing. In view of the limited association between the prefecture-level health system inputs and health outcomes, the potential sources of regional variations, including subnational health system performance, urgently need assessment.FundingBill & Melinda Gates Foundation, Japan Ministry of Education, Science, Sports and Culture, Japan Ministry of Health, Labour and Welfare, AXA CR Fixed Income Fund and AXA Research Fund

SBML Level 3: an extensible format for the exchange and reuse of biological models

Abstract Systems biology has experienced dramatic growth in the number, size, and complexity of computational models. To reproduce simulation results and reuse models, researchers must exchange unambiguous model descriptions. We review the latest edition of the Systems Biology Markup Language (SBML), a format designed for this purpose. A community of modelers and software authors developed SBML Level 3 over the past decade. Its modular form consists of a core suited to representing reaction‐based models and packages that extend the core with features suited to other model types including constraint‐based models, reaction‐diffusion models, logical network models, and rule‐based models. The format leverages two decades of SBML and a rich software ecosystem that transformed how systems biologists build and interact with models. More recently, the rise of multiscale models of whole cells and organs, and new data sources such as single‐cell measurements and live imaging, has precipitated new ways of integrating data with models. We provide our perspectives on the challenges presented by these developments and how SBML Level 3 provides the foundation needed to support this evolution

SBML Level 3: an extensible format for the exchange and reuse of biological models

Systems biology has experienced dramatic growth in the number, size, and complexity of computational models. To reproduce simulation results and reuse models, researchers must exchange unambiguous model descriptions. We review the latest edition of the Systems Biology Markup Language (SBML), a format designed for this purpose. A community of modelers and software authors developed SBML Level 3 over the past decade. Its modular form consists of a core suited to representing reaction-based models and packages that extend the core with features suited to other model types including constraint-based models, reaction-diffusion models, logical network models, and rule-based models. The format leverages two decades of SBML and a rich software ecosystem that transformed how systems biologists build and interact with models. More recently, the rise of multiscale models of whole cells and organs, and new data sources such as single-cell measurements and live imaging, has precipitated new ways of integrating data with models. We provide our perspectives on the challenges presented by these developments and how SBML Level 3 provides the foundation needed to support this evolution