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Murdannia nudiflora (L.) Brenan is a day flower that is dependent on entomophilous pollination. Despite the lack of pollinator attractants and its short flower longevity, M. nudiflora shows high rates of fecundity, which lead to their rapid dispersal. In addition to monitoring the vegetative reproductive methods and the effect of select environmental parameters (atmospheric temperature, relative humidity, and precipitation rates) in M. nudiflora, we evaluated mating systems in this species via artificial crosses. This species has evolved to undergo autogamy to ensure reproductive success when pollinators are insufficient; cleistogamous flowers are produced for optimal pollinator activity when environmental conditions are unfavorable. The number of cleistogamous flowers produced was found to be positively correlated with humidity and precipitation rates, and negatively correlated with temperature. In addition, it was found that high humidity and precipitation always hinder insect pollinators. Therefore, the combination of vegetative reproduction, entomophily, and cleistogamous self-pollination helps this weedy species to propagate with maximum efficiency. Murdannia nudiflora employs pre-anthesis cleistogamy as a mating strategy for reproductive assurance while retaining mechanisms that promote out-crossing. Key words: anthesis, breeding systems, chasmogamous, entomophilous, pollen viability, spontaneous autogamy. Murdannia nudiflora (L.) Brenan est une espece dont les fleurs fletrissent rapidement qui depend de la pollinisation entomophile. Malgre l'absence de substances attractives pour les pollinisateurs et la faible longevite de ses fleurs, M. nudiflora presente de hauts taux de fecondite qui donnent lieu a sa dispersion rapide. En plus de suivre les methodes de reproduction vegetative et l'effet de parametres environnementaux selectionnes (temperature atmospherique, humidite relative et taux de precipitation), les auteurs ont evalue les systemes de reproduction chez cette espece au moyen de croisements artificiels. Cette espece a evolue vers l'autogamie afin d'assurer son succes reproducteur lorsque les pollinisateurs sont en nombre insuffisant; les fleurs cleistogames sont produites pour optimiser l'activite des pollinisateurs lorsque les conditions environnementales sont defavorables. Le nombre de fleurs cleistogames produites s'avere correle positivement avec les taux d'humidite et de precipitations, et correle negativement avec la temperature. Par ailleurs, il appert qu'une humidite et des precipitations elevees genent toujours les insectes pollinisateurs. Ainsi, la combinaison de la reproduction vegetative, de l'entomophilie et de l'autofecondation cleistogame aide cette espece de mauvaise herbe a se propager avec une efficacite maximale. Murdannia nudiflora utilise la cleistogamie preanthese comme strategie pour assurer sa reproduction tout en conservant des mecanismes qui favorisent le croisement eloigne. [Traduit par la Redaction] Mots-cles : anthese, systeme de reproduction, chasmogame, entomophile, viabilite du pollen, autogamie spontanee., Introduction Murdannia Royle is a genus within the dayflower family Commelinaceae, which includes 61 species worldwide. The genus is primarily Asiatic, with species inhabiting diverse habitats. Murdannia nudiflora (L.) Brenan, [...]

The ocean-atmosphere interface (OAI) is a dynamic boundary of complex energy and chemical exchange and is important to understand mechanisms that influence it. Research is on-going to improve how the OAI is represented within tropical cyclone (TC) prediction models and ensembles. Motivation for improvement stems from a rapidly changing thermodynamic environment caused by climate change. Such changes are not widely understood, as no scientist has observed or measured these changes on long time scales. We assert the possibility of climate change, its underlying uncertainties and modified atmospheric variability can potentially lead to rapid intensification. We argue simplification of OAI to capture model ensemble data uncertainty through probabilistic modeling via Bayesian Neural Network (BNN). We retrieved area--averaged satellite data from NOAA and NASA, created a data set of several parameters--atmospheric air temperature (AirTemp), atmospheric temperature anomaly (ATA), atmospheric carbon dioxide (C[O.sub.2]), sea surface temperature (SST), tropical cyclone heat potential (TCHP), mid- layer wind shear (WindShear), convective available heat potential (CAPE), vertical motions (VerticalMotion), precipitable water content (PWC) and our derived OAI parameter as inputs into a BNN via R programming language. We used the BNN to model the OAI and inferenced potential favorability of an OAI given conditional probabilities. The BNN network rejected ATA and WindShear. Results showed probabilities acceptable within expert interpretations of parameter interactions to predict favorable OAI conditions. Keywords: Tropical Storm, Bayesian Neural Network, Ocean-Atmosphere Interface, INTRODUCTION Uncertainties in tropical cyclone (TC) intensification forecasting continue in modern-day forecasting modelsl. Recent storms such as TC Matthew (2016) and TC Irma (2017) demonstrated our limitations in predicting intensification, [...]

Researchers plan to spray sunlight-reflecting particles into the stratosphere, an approach that could ultimately be used to quickly lower the planet's temperature.Researchers plan to spray sunlight-reflecting particles into the stratosphere, an approach that could ultimately be used to quickly lower the planet's temperature., Author(s): Jeff TollefsonAuthor Affiliations:First sun-dimming experiment will test a way to cool Earth Frank Keutsch, Zhen Dai and David Keith (left to right) in Keutsch's laboratory at Harvard University. [see [...]