Maize Leaf Appearance Rates: A Synthesis From the United States Corn Belt

The relationship between collared leaf number and growing degree days (GDD) is crucial for predicting maize phenology. Biophysical crop models convert GDD accumulation to leaf numbers by using a constant parameter termed phyllochron (°C-day leaf−1) or leaf appearance rate (LAR; leaf oC-day−1). However, such important parameter values are rarely estimated for modern maize hybrids. To fill this gap, we sourced and analyzed experimental datasets from the United States Corn Belt with the objective to (i) determine phyllochron values for two types of models: linear (1-parameter) and bilinear (3-parameters; phase I and II phyllochron, and transition point) and (ii) explore whether environmental factors such as photoperiod and radiation, and physiological variables such as plant growth rate can explain variability in phyllochron and improve predictability of maize phenology. The datasets included different locations (latitudes between 48° N and 41° N), years (2009–2019), hybrids, and management settings. Results indicated that the bilinear model represented the leaf number vs. GDD relationship more accurately than the linear model (R2 = 0.99 vs. 0.95, n = 4,694). Across datasets, first phase phyllochron, transition leaf number, and second phase phyllochron averaged 57.9 ± 7.5°C-day, 9.8 ± 1.2 leaves, and 30.9 ± 5.7°C-day, respectively. Correlation analysis revealed that radiation from the V3 to the V9 developmental stages had a positive relationship with phyllochron (r = 0.69), while photoperiod was positively related to days to flowering or total leaf number (r = 0.89). Additionally, a positive nonlinear relationship between maize LAR and plant growth rate was found. Present findings provide important parameter values for calibration and optimization of maize crop models in the United States Corn Belt, as well as new insights to enhance mechanisms in crop models

Characterization of the mechanisms underlying the crosstalk between galectins and notch in gastric cancer

Gastric cancer is the fourth most common cancer and the second leading cause of cancer-related deaths worldwide. Galectins form a family of β-galactosides binding proteins that recognize a variety of glycan-containing proteins at the cell surface and are overexpressed in various tumors, including gastric cancer. Galectins overexpression as well as changes in their subcellular distribution has been associated with gastric cancer progression and poor prognosis. It is not well understood, however, how the interaction between galectins and glycosylated receptors modulates tumor development and growth. Since Notch receptors and ligands contain glycan structures known to bind galectins, we aim to demonstrate that galectins expression in the tumor microenvironment may interfere with Notch signaling activation during tumor development and progression.\ud \ud Materials and methods\ud Immunoprecipitation procedures with gastric cancer cell line AGS (ATCC CRL-1739) and MKN45 (ACC 409) were used to test for association between galectin-1/-3 and Notch-1 receptor. Furthermore, we transfected AGS cell line with siRNA against galectin-1/-3 or scramble using standard protocols (IDT DNA technologies), stimulate them with immobilized human recombinant delta-4 or Jagged-1 and assessed Notch-1 receptor activation.\ud \ud Results\ud Galectin-1 and -3 interact with Notch-1 receptor and differentially modulate Notch signaling pathway upon activation by Delta/Jagged ligands. Galectin-1 knockdown alters Notch-1 activation induced by Delta-4 whereas galectin-3 knockdown alters jagged-1-mediated Notch-1 activation. Furthermore, we found that exogenously added galectin-3 can enhance Notch-1 activation by Jagged-1.\ud \ud Conclusion\ud Our results suggest that galectin-1 and -3 interact with Notch-1 receptor and differentially modulate Notch signaling activation induced by Jagged-1 and Delta-4

Anti-inflammatory response to acute exercise is related with intensity and physical fitness

Purpose: The relationship between inflammatory markers and energetic metabolism has been explored. However, the relation between exercise intensity and fitness-status is unclear and it is necessary to understand this relationship to apply specific exercise guidance. The purpose of the study was to analyze metabolic and inflammatory responses imposed by acute exercise sessions performed at moderate, heavy and severe intensities and their relationship with physical fitnessstatus. Methods: Nineteen healthy male volunteers performed three acute exercise sessions until exhaustion or up to 60 minutes on a cycle ergometer at moderate (90% of VT1), heavy (midpoint between VT1/VT2), and severe (midpoint between VT2/Wmax) intensities. Blood lactate, glucose, NEFA, endotoxin and cytokines were determined for each exercise session. Peripheral and LPS-stimulated release of TNF-α, IL-6 and IL-10 were analyzed pre, post and 60-min after sessions. Results: In peripheral blood, severe intensity increased lactate, endotoxin and TNF-α immediately post-exercise and glucose at 60-min post-exercise. There was a trend for IL-10 increase at 60-min post-exercise in peripheral blood. Immediately post-exercise, LPS-stimulated TNF-α, IL-6, IL-6/IL-10 ratio and lactate levels were higher in the severe intensity while NEFA levels decreased at this time. At 60-min post-exercise higher concentrations of glucose and a trend for increased IL-10 were observed in severe intensity. Positive correlation was observed between maximal aerobic power and IL-10 (r=0.513, p=0.042) and negative correlations between maximal aerobic power and endotoxin (r=-0.531, p=0.034) and lactate (r=-0.538, p=0.031) in heavy intensity. Conclusion: Our data show a novel finding that higher cytokine responses occur at higher intensities, mainly in severe intensity. However, the anti-inflammatory (IL-10) response was physical fitness-dependent

Levantamento preliminar de térmitas em bosques de mangues na Reserva Ecológica da Michelin, Igrapiúna, Bahia, Brasil

Aiming at providing a background for the establishment of a Management and Conservation Plan for the Michelin Ecological Reserve, located in Camamu Bay, Bahia State, we analyzed the diversity and structure of termite communities occurring in mangrove vegetation in this area. Five 3 x 100 m unconnected transects were setup, each one subdivided in 10 sections measuring 3 x 10 m. Three morphospecies, belonging to two genera of termites, were found: Nasutitermes sp1 (64,71%), Nasutitermes sp2 (23,53%) e Termes sp (11,76%), present in 17 samples. Nasutitermes was the most abundant genus, as a result of the wide ecological valence demonstrated by this taxonomic group, which is able to build epigeic or tree nests, increasing the likelihood of mangrove colonization, an environment constantly flooded and soaked.Com o propósito de fornecer subsídios para a criação do plano de Manejo e Conservação da Reserva Ecológica da Michelin, localizada na Bahia de Camamú-Ba, analisamos a diversidade e a estrutura da comunidade de cupins que ocorrem em bosques de manguezais daquela localidade. Foram demarcados 5 transectos não conectados, com 3m x 100m, subdivididos em 10 seções de 3m x 10m. Foram encontradas 3 morfoespécies de 2 gêneros de cupins: Nasutitermes sp1 (64,71%), Nasutitermes sp2 (23,53%) e Termes sp. (11,76%) num total de 17 amostras coletadas. Nasutitermes foi o gênero mais abundante, resultado da ampla valência ecológica demonstrada por este grupo, capaz de construir ninhos epígeos ou arborícolas, ampliando a possibilidade de colonização em manguezal, cujo solo se mantém periodicamente inundado e encharcado

Engaging Undergraduates in Science Research: Not Just About Faculty Willingness.

Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members' decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members' likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute's 2007-2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed

Religiosity and corporate financial reporting: evidence from a European country

Using a sample of Portuguese privately-held firms, I examine the association between religiosity and financial reporting quality. The results suggest that firms headquartered in Portuguese areas with strong religious adherence and in the core area of the Portuguese religious cult (the district where the Fátima Sanctuary is located) generally experience lower incidence of earnings management. I provide further evidence that the results are robust to alternative measures of religiosity, and that are not driven by firms headquartered in rural areas. I also conclude that religious social norms, together with other forms of external financial monitoring, represent a mechanism for reducing costly agency conflicts. While the religious practice declined in the last decades in Portugal, I provide evidence that, even in a such context, religiosity is associated with reduced acceptance of unethical business practices, in particular, with reduced acceptance of aggressive accounting practices.I thank participants of the Second Paris Financial Management Conference (PFMC, 2014) and the 3RD Workshop on Business Ethics (EIASM, 2015) for their helpful insights.info:eu-repo/semantics/publishedVersio

Structural power and the evolution of collective fairness in social networks

From work contracts and group buying platforms to political coalitions and international climate and economical summits, often individuals assemble in groups that must collectively reach decisions that may favor each part unequally. Here we quantify to which extent our network ties promote the evolution of collective fairness in group interactions, modeled by means of Multiplayer Ultimatum Games (MUG). We show that a single topological feature of social networks-which we call structural power-has a profound impact on the tendency of individuals to take decisions that favor each part equally. Increased fair outcomes are attained whenever structural power is high, such that the networks that tie individuals allow them to meet the same partners in different groups, thus providing the opportunity to strongly influence each other. On the other hand, the absence of such close peer-influence relationships dismisses any positive effect created by the network. Interestingly, we show that increasing the structural power of a network leads to the appearance of well-defined modules-as found in human social networks that often exhibit community structure-providing an interaction environment that maximizes collective fairness.This research was supported by Fundacao para a Ciencia e Tecnologia (FCT) through grants SFRH/BD/94736/2013, PTDC/EEI-SII/5081/2014, PTDC/MAT/STA/3358/2014 and by multi-annual funding of CBMA and INESC-ID (under the projects UID/BIA/04050/2013 and UID/CEC/50021/2013) provided by FCT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio