Impact of limited solvent capacity on metabolic rate, enzyme activities, and metabolite concentrations of S. cerevisiae glycolysis

The cell's cytoplasm is crowded by its various molecular components, resulting in a limited solvent capacity for the allocation of new proteins, thus constraining various cellular processes such as metabolism. Here we study the impact of the limited solvent capacity constraint on the metabolic rate, enzyme activities, and metabolite concentrations using a computational model of Saccharomyces cerevisiae glycolysis as a case study. We show that given the limited solvent capacity constraint, the optimal enzyme activities and the metabolite concentrations necessary to achieve a maximum rate of glycolysis are in agreement with their experimentally measured values. Furthermore, the predicted maximum glycolytic rate determined by the solvent capacity constraint is close to that measured in vivo. These results indicate that the limited solvent capacity is a relevant constraint acting on S. cerevisiae at physiological growth conditions, and that a full kinetic model together with the limited solvent capacity constraint can be used to predict both metabolite concentrations and enzyme activities in vivo. © 2008 Vazquez et al

Surface heat fluxes over the northern Arabian Gulf and the northern Red Sea: Evaluation of ECMWF-ERA5 and NASA-MERRA2 reanalyses

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Al Senafi, F., Anis, A., & Menezes, V. Surface heat fluxes over the northern Arabian Gulf and the northern Red Sea: Evaluation of ECMWF-ERA5 and NASA-MERRA2 reanalyses. Atmosphere, 10(9), (2019): 504, doi:10.3390/atmos10090504.The air–sea heat fluxes in marginal seas and under extreme weather conditions constitute an essential source for energy transport and mixing dynamics. To reproduce these effects in numerical models, we need a better understanding of these fluxes. In response to this demand, we undertook a study to examine the surface heat fluxes in the Arabian Gulf (2013 to 2014) and Red Sea (2008 to 2010)—the two salty Indian Ocean marginal seas. We use high-quality buoy observations from offshore meteorological stations and data from two reanalysis products, the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA2) from the National Aeronautics and Space Administration (NASA) and ERA5, the fifth generation of the European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalyses of global climate. Comparison of the reanalyses with the in situ-derived fluxes shows that both products underestimate the net heat fluxes in the Gulf and the Red Sea, with biases up to −45 W/m 2 in MERRA2. The reanalyses reproduce relatively well the seasonal variability in the two regions and the effects of wind events on air–sea fluxes. The results suggest that when forcing numerical models, ERA5 might provide a preferable dataset of surface heat fluxes for the Arabian Gulf while for the Red Sea the MERRA2 seems preferable.This study was funded by the Research Sector at Kuwait University (project #ZS03/16) and by NSF (grant #OCE-1435665) supporting V.M

Conhecimento de Geometria de estudantes da Licenciatura em Educação Básica

This quantitative study aims to assess the development of geometry knowledge of over two hundred students attending Basic Education course in three Schools of Education. Through a test with 21 questions, handed over before and after training in Geometry, students are assessed in a set of categories. The results reveal that although students demonstrate knowledge of elementary concepts at the outset, with percentages of success above 70%, and evolution at the three schools, with an average increase of 5%, also reveal critical aspects related to basic concepts covered in the test

Characterization of written languages using structural features from common corpora

This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordFor more than 5,000 years, we have been communicating using some form of written language. For many scholars, the advent of written language contributed to the development of societies because it enabled knowledge to be passed to future generations without considerable loss of information or ambiguity. Today, it is estimated that we use about 7,000 languages to communicate, but the majority of these do not have a written form; in fact, there are no reliable estimates of how many written languages exist today. There are three main families of written languages: Afro-Asiatic, Indo-European, and Turkic. These families of languages are based on historical family-trees. However, with the amount of data available today, one can start looking at language classification using regularities extracted from corpora of text. This paper focus on regularities of 10 languages from the mentioned families. In order to find features for these languages we use (1) Heaps’ law, which models the number of distinct words in a corpus as a function of the total number of words in the same corpora, and (2) structural properties of networks created from word co-occurrence in large corpora for different languages. Using clustering approaches we show that despite differences from years of being used in separate countries, the clustering still seem to respect some historical organization of families

In Liquid Plasma for Surface Engineering of Cu Electrodes with Incorporated SiO2 Nanoparticles From Micro to Nano

A robust and efficient route to modify the chemical and physical properties of polycrystalline copper Cu wires via versatile plasma electrolysis is presented. Silica SiO2 nanoparticles 11 nm are introduced during the electrolysis to tailor the surface structure of the Cu electrode. The influence of these SiO2 nanoparticles on the structure of the Cu electrodes during plasma electrolysis over a wide array of applied voltages and processing time is investigated systematically. Homogeneously distributed 3D coral like microstructures are observed by scanning electron microscopy on the Cu surface after the in liquid plasma treatment. These 3D microstructures grow with increasing plasma processing time. Interestingly, the microstructured copper electrode is composed of CuO as a thin outer layer and a significant amount of inner Cu2O. Furthermore, the oxide film thickness between 1 and 70 m , the surface morphology, and the chemical composition can be tuned by controlling the plasma parameters. Remarkably, the fabricated microstructures can be transformed to nanospheres assembled in coral like microstructures by a simple electrochemical treatmen

On the performance of network science metrics as long-term investment strategies in stock markets

This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this recordInternational Conference on Complex Networks and their Applications - COMPLEX NETWORKS 2017: Complex Networks & Their Applications VIFirms and individuals have always searched for investment strategies that perform well and are robust to market variations. Over the years, many strategies have claimed to be effective but few resist the effect of time, that is, most of them become outdated. It turns out that markets have a “self-correcting ability”; the secretive/novel nature of strategies firms employ cannot win forever; other firms eventually implement competing strategies causing the market to adjust. Nowadays, most investment firms “sell” to their clients two approaches: high reward and low reward. Unfortunately the possibility of high reward is generally coupled with low robustness (volatility) and if one wants high robustness the yields are low (low reward). In this paper, we use an approach based on network characteristics extracted from historical market data. Network Science has argued that all complex systems have an underlying network structure that explains the behavior of the system. With this in mind, we propose a long-term investment strategy that builds a network from historical investment data, and considers the current state of this network to decide how to create portfolios. We argue that our approach performs better than standard long-term approaches

Host Plant Record for the Fruit Flies, Anastrepha fumipennis and A. nascimentoi (Diptera, Tephritidae)

The first host plant record for Anastrepha fumipennis Lima (Diptera: Tephritidae) in Geissospermum laeve (Vell.) Baill (Apocynaceae) and for A. nascimentoi Zucchi found in Cathedra bahiensis Sleumer (Olacaceae) was determined in a host plant survey of fruit flies undertaken at the “Reserva Natural da Companhia Vale do Rio Doce”. This reserve is located in an Atlantic Rain Forest remnant area, in Linhares county, state of Espírito Santo, Brazil. The phylogenetic relationships of Anastrepha species and their hosts are discussed. The occurrence of these fruit fly species in relation to the distribution range of their host plants is also discussed

A Comparison of Total Food Intake at a Personalised Buffet in People with Obesity, before and 24 Months after Roux-en-Y-Gastric Bypass Surgery

Long-term reductions in the quantity of food consumed, and a shift in intake away from energy dense foods have both been implicated in the potent bariatric effects of Roux-en-Y gastric bypass (RYGB) surgery. We hypothesised that relative to pre-operative assessment, a stereotypical shift to lower intake would be observed at a personalised ad libitum buffet meal 24 months after RYGB, driven in part by decreased selection of high energy density items. At pre-operative baseline, participants (n = 14) rated their preference for 72 individual food items, each of these mapping to one of six categories encompassing high and low-fat choices in combination with sugar, complex carbohydrate or and protein. An 18-item buffet meal was created for each participant based on expressed preferences. Overall energy intake was reduced on average by 60% at the 24-month buffet meal. Reductions in intake were seen across all six food categories. Decreases in the overall intake of all individual macronutrient groups were marked and were generally proportional to reductions in total caloric intake. Patterns of preference and intake, both at baseline and at follow-up appear more idiosyncratic than has been previously suggested by verbal reporting. The data emphasise the consistency with which reductions in ad libitum food intake occur as a sequel of RYGB, this being maintained in the setting of a self-selected ad libitum buffet meal. Exploratory analysis of the data also supports prior reports of a possible relative increase in the proportional intake of protein after RYGB