Influence of agronomic conditions on the efficacy of different fungicides applied to wheat at heading: effect on flag leaf senescence, Fusarium head blight attack, grain yield and deoxynivalenol contamination

A series of field experiments has been conducted in North West Italy over a period of 3 years to evaluate the effect of fungicide applications on common wheat yield and safety, combined with different agronomic conditions (high: a susceptible variety to FHB planted in an untilled field; low: a medium tolerant variety to FHB planted in a ploughed field) for Fusarium head blight (FHB) infection risk. A azole mixture (prochloraz + epoxiconazole), applied at heading, was compared in each year and for each agronomic condition with a triazole with high activity against F. graminearum and F. culmorum (metconazole), a strobilurin-azole mixture with elevated action to control leaf diseases and delay leaf senescence (azoxystrobin + prochloraz) and an untreated control. The following parameters were analyzed: flag leaf greenness, grain yield, test weight, thousand kernel weight (TKW), FHB incidence and severity and deoxynivalenol (DON) contamination. The results of this research, conducted over three years with different meteorological conditions, underline the important link between fungicide efficacy and environmental and agronomic conditions that can influence fungal disease pressure. The fungicide effect on the control of FHB and the increase in flag leaf longevity and grain yield were greater with an increase in the disease pressure. On the other hand, the DON contamination was reduced by the fungicide to a greater extent in the low risk agronomic and environmental conditions compared to the high risk ones. Prochloraz + epoxiconazole showed a lower efficacy in reducing DON contamination compared to metconazole, particularly in the higher FHB pressure conditions. No significant differences were observed between the azole mixture and the strobilurin-azole mixture for flag leaf greenness, grain yield, test weight or TKW. This study provides useful information that can be used to evaluate, in naturally-infected field conditions, the effect of a fungicide application at heading on wheat yield and safety in distinct scenarios for FHB and foliar disease pressure

The Lyman-continuum-leaking super star cluster in the Sunburst Arc and its surrounding nebula

Strong lensing offers a precious opportunity for studying the formation and early evolution of super star clusters that are rare in our cosmic backyard. The Sunburst Arc, a lensed Cosmic Noon galaxy, hosts a young super star cluster with escaping Lyman continuum radiation. Analyzing archival HST images and emission line data from VLT/MUSE and X-shooter, we construct a physical model for the cluster and its surrounding photoionized nebula. We confirm that the cluster is \sim 3\mbox{--}4\,Myr old, is extremely massive $M_\star \sim 10^7\,M_\odot$ and yet has a central component as compact as several parsecs, and we find a metallicity $Z=(0.26\pm0.03)\,Z_\odot$. The cluster is surrounded by $\gtrsim 10^5\,M_\odot$ of dense clouds that have been pressurized to $P\sim 10^9\,{\rm K}\,{\rm cm}^{-3}$ by perhaps stellar radiation at within ten parsecs. These should have large neutral columns $N_{\rm HI} > 10^{22.5}\,{\rm cm}^{-2}$ to survive rapid ejection by radiation pressure. The clouds are likely dusty as they show gas-phase depletion of silicon, and may be conducive to secondary star formation if $N_{\rm HI} > 10^{24}\,{\rm cm}^{-2}$ or if they sink further toward the cluster center. Detecting strong ${\rm N III]}\lambda\lambda$1750,1752, we infer heavy nitrogen enrichment $\log({\rm N/O})=-0.23^{+0.08}_{-0.11}$. This requires efficiently retaining $\gtrsim 500\,M_\odot$ of nitrogen in the high-pressure clouds from massive stars heavier than $60\,M_\odot$ up to 4 Myr. We suggest a physical origin of the high-pressure clouds from partial or complete condensation of slow massive star ejecta, which may have important implication for the puzzle of multiple stellar populations in globular clusters.Comment: 25 pages, 10 figure

Advanced Waste-to-energy Steam Cycles

AbstractThis paper focuses on possibilities to maximize waste conversion through integration of a Waste-To-Energy (WTE) plant with a gas turbine (GT). In particular, this study investigates the feasibility of utilizing the hot gases leaving the GT mainly to superheat the steam leaving the WTE steam generator. A parametric investigation on the steam production is carried out and the optimum plant match condition in terms of plants capacity ratio is identified and discussed. Detailed modifications to a typical WTE cycle arrangement are presented, in order to evaluate the resulting performance enhancement. Numerical results of a conventional reference WTE plant repowering with different GT commercial units are shown and discussed. Performance indexes, specifically introduced in order to assess the proposed integrated configuration and to allocate power output to each input fuel are illustrated and applied on the considered plant. Results of the study suggest possibilities to create new advanced WTE-GT integrated power plants or to repower existing WTE plants, in order to increase waste to energy conversion

Technologies for harvesting microalgae for biodiesel production: a comparative LCA study

In recent years, Life Cycle Assessment (LCA) has been used in multiple studies to evaluate the environmental benefits resulting from the production of biofuel from microalgae. Literature in this field shows that one of the main issues associated with biofuel production is energy consumption during the harvest of microalgae algae, largely due to the high yield of dry matter required for the subsequent production of biodiesel. To date, no existing LCAs have specifically focused on assessing alternative approaches to harvest microalgae. The aim of this paper is to analyze the utilization of emerging and innovative technologies for microalgae harvest, in terms of changing environmental impacts associated with biodiesel production, utilizing a case study in Ontario, Canada. An LCA model will be developed applied to four different scenarios, based on the use of four alternative harvest technologies. These technologies include (1) APIm-modified CNC, (2) modified magnetic nanoparticles (MNP), and (3) bacteria for algal separation. An additional scenario (4) will examine a system that avoids dry matter concentration and moves directly from microalgae production straight to lipid extraction. In each scenario, increasing algae harvesting efficiency is examined based on both microalgae species and the harvesting technology adopted, and potential environmental and economic benefits associated with biodiesel production are quantified. The case study in Ontario, Canada, is informed by partnership with industrial partners (a cement company and a water treatment utility) who have provided primary data to the study. The LCAs will be carried out in a fashion designed to allow comparison across all harvest scenarios, using a common model developed in Simapro. Different impact assessment methodologies will also be considered in the analysis, in order to characterize the sensitivity of the obtained results

A Latent Dirichlet Allocation Approach using Mixed Graph of Terms for Sentiment Analysis

The spread of generic (as Twitter, Facebook orGoogle+) or specialized (as LinkedIn or Viadeo) social networks allows to millions of users to share opinions on different aspects of life every day. Therefore this information is a rich source of data for opinion mining and sentiment analysis. This paper presents a novel approach to the sentiment analysis based on the Latent Dirichlet Allocation (LDA) approach. The proposed methodology aims to identify a word-based graphical model (we call it a mixed graph of terms) for depicting a positive or negative attitude towards a topic. By the use of this model it will be possible to automatically mine from documents positive and negative sentiments.Experimental evaluation, on standard and real datasets, shows that the proposed approach is effective and furnishes good and reliable results

comparative lca of flocculation for the harvesting of microalgae for biofuels production

Abstract In recent years, the use of Life Cycle Analysis (LCA) to evaluate environmental benefits resulting from the production of biofuel from microalgae has continued to evolve. Literature in this field shows that one of the main challenges associated with the effect of biofuel production on the environment is the high energy consumption necessary in the microalgae harvesting phase to achieve the level of dewatering required to the next steps. Moreover, detailed LCAs specifically focused on the assessment of alternative technologies for the harvesting of microalgae have yet to be presented. As such, the aim of this paper is to analyze the potential environmental benefits and shortcomings arising from the use of flocculation for the harvesting of microalgae in the biofuel production process, with particular attention to the Canadian context. The method employed is a comparative LCA, where two alternative scenarios based on the application of two harvesting technologies are taken into account: (1) flocculation and centrifugation and (2) direct centrifugation (without flocculation). The calculations of environmental impact and the sensitivity analysis are performed with the SimaPro software

Comparative assessment of autochthonous bacterial and fungal communities and microbial biomarkers of polluted agricultural soils of the Terra dei Fuochi

Organic and inorganic xenobiotic compounds can affect the potential ecological function of the soil, altering its biodiversity. Therefore, the response of microbial communities to environmental pollution is a critical issue in soil ecology. Here, a high-throughput sequencing approach was used to investigate the indigenous bacterial and fungal community structure as well as the impact of pollutants on their diversity and richness in contaminated and noncontaminated soils of a National Interest Priority Site of Campania Region (Italy) called “Terra dei Fuochi”. The microbial populations shifted in the polluted soils via their mechanism of adaptation to contamination, establishing a new balance among prokaryotic and eukaryotic populations. Statistical analyses showed that the indigenous microbial communities were most strongly affected by contamination rather than by site of origin. Overabundant taxa and Actinobacteria were identified as sensitive biomarkers for assessing soil pollution and could provide general information on the health of the environment. This study has important implications for microbial ecology in contaminated environments, increasing our knowledge of the capacity of natural ecosystems to develop microbiota adapted to polluted soil in sites with high agricultural potential and providing a possible approach for modeling pollution indicators for bioremediation purposes

Candida-associated denture stomatitis

Candida albicans is a dimorphic yeast strongly gram positive able to live as normal commensal organism in the oral cavity of healthy people. It is the yeast more frequently isolated in the oral cavity. Under local and systemic factors related to the host conditions, it becomes virulent and responsible of oral diseases known as oral candidiasis. It has been shown that the presence of denture is a predisposing factor to the onset of pathologies related to C. albicans. Clinical studies have shown that C. albicans is not only able to adhere to the mucous surfaces, but also to stick to the acrylic resins of the dental prostheses. Both the plaque accumulated on the denture and the poor oral hygiene contribute to the virulence of Candida, offering the clinical picture of Candida-associated denture stomatitis. The therapeutic strategies currently adopted in the clinical practice to overcome these fungal infections provide for the use of topical and/or systemic antifungal and topical antiseptics and disinfectants, the irradiation with microwaves and the accurate mechanical removal of the bacterial plaque from the denture surfaces and from the underlying mucosa. A correct oral hygiene is important for the control of the bacterial biofilm present on the denture and on the oral mucosa and it is the fundamental base for the prophylaxis and the therapy of the Candidaassociated denture stomatitis

Toxigenic fungi and mycotoxins in a climate change scenario: Ecology, genomics, distribution, prediction and prevention of the risk

Toxigenic fungi and mycotoxins are very common in food crops, with noticeable differences in their host specificity in terms of pathogenicity and toxin contamination. In addition, such crops may be infected with mixtures of mycotoxigenic fungi, resulting in multi-mycotoxin contamination. Climate represents the key factor in driving the fungal community structure and mycotoxin contamination levels pre- and post-harvest. Thus, there is significant interest in understanding the impact of interacting climate change-related abiotic factors (especially increased temperature, elevated CO2 and extremes in water availability) on the relative risks of mycotoxin contamination and impacts on food safety and security. We have thus examined the available information from the last decade on relative risks of mycotoxin contamination under future climate change scenarios and identified the gaps in knowledge. This has included the available scientific information on the ecology, genomics, distribution of toxigenic fungi and intervention strategies for mycotoxin control worldwide. In addition, some suggestions for prediction and prevention of mycotoxin risks are summarized together with future perspectives and research needs for a better understanding of the impacts of climate change scenarios