657 research outputs found
Tsunami scenarios in the Mediterranean
We calculated the impact on Southern Italy of a large set of tsunamis resulting from earthquakes generated by major fault zones of the Mediterranean Sea. Our approach merges updated knowledge on the regional tectonic setting and scenario-like calculations of expected tsunami impact.
We selected three potential source zones located at short, intermediate and large distance from our target coastlines: the Southern Tyrrhenian thrust belt; the Tell-Atlas thrust belt; and the western Hellenic Arc. For each zone we determined a Maximum Credible Earthquake and described the geometry, kinematics and size of its associated Typical Fault. We then let the Typical Fault float along strike of its parent source zone and simulated all tsunamis it could trigger. Simulations are based on the solution of the nonlinear shallow water equations through a finite-difference technique. For each run we calculated the wave fields at desired simulation times and the maximum water elevation field, then produced travel-time maps and maximum wave-height profiles along the target coastlines.
The results show a highly variable impact for tsunamis generated by the different source zones. For example, a large Hellenic Arc earthquake will produce a much higher tsunami wave (up to 5 m) than those of the other two source zones (up to 1.5 m). This implies that tsunami scenarios for Mediterranean Sea countries must necessarily be computed at the scale of the entire basin. Our work represents a pilot study for constructing a basin-wide tsunami scenario database to be used for tsunami hazard assessment and early warning
Nuovi orientamenti di ricerca e sviluppo con funghi antagonisti alla luce del “Piano Strategico Nazionale per lo Sviluppo del Sistema Biologico”.
Autotrophic and Heterotrophic Growth Conditions Modify Biomolecole Production in the Microalga Galdieria sulphuraria (Cyanidiophyceae, Rhodophyta)
Algae have multiple similarities with fungi, with both belonging to the Thallophyte, a polyphyletic group of non-mobile organisms grouped together on the basis of similar characteristics, but not sharing a common ancestor. The main difference between algae and fungi is noted in their metabolism. In fact, although algae have chlorophyll-bearing thalloids and are autotrophic organisms, fungi lack chlorophyll and are heterotrophic, not able to synthesize their own nutrients. However, our studies have shown that the extremophilic microalga Galderia sulphuraria (GS) can also grow very well in heterotrophic conditions like fungi. This study was carried out using several approaches such as scanning electron microscope (SEM), gas chromatography/mass spectrometry (GC/MS), and infrared spectrophotometry (ATR-FTIR). Results showed that the GS, strain ACUF 064, cultured in autotrophic (AGS) and heterotrophic (HGS) conditions, produced different biomolecules. In particular, when grown in HGS, the algae (i) was 30% larger, with an increase in carbon mass that was 20% greater than AGS; (ii) produced higher quantities of stearic acid, oleic acid, monounsaturated fatty acids (MUFAs), and ergosterol; (iii) produced lower quantities of fatty acid methyl esters (FAMEs) such as methyl palmytate, and methyl linoleate, saturated fatty acids (SFAs), and poyliunsaturated fatty acids (PUFAs). ATR-FTIR and principal component analysis (PCA) statistical analysis confirmed that the macromolecular content of HGS was significantly different from AGS. The ability to produce different macromolecules by changing the trophic conditions may represent an interesting strategy to induce microalgae to produce different biomolecules that can find applications in several fields such as food, feed, nutraceutical, or energy production
Cross-talk between signaling pathways leading to defense against pathogens and insects
In nature, plants interact with a wide range of organisms, some of which
are harmful (e.g. pathogens, herbivorous insects), while others are beneficial
(e.g. growth-promoting rhizobacteria, mycorrhizal fungi, and predatory
enemies of herbivores). During the evolutionary arms race between plants
and their attackers, primary and secondary immune responses evolved to
recognize common or highly specialized features of microbial pathogens
(Chisholm et al., 2006), resulting in sophisticated mechanisms of defense
Total synthesis and biological evaluation of the tetramic acid based natural product harzianic acid and its stereoisomers
Financial support for this project was provided by Cancer Research UK (Grant No. C21383/A6950)The bioactive natural product harzianic acid was prepared for the first time in just six steps (longest linear sequence) with an overall yield of 22%. The identification of conditions to telescope amide bond formation and a Lacey-Dieckmann reaction into one pot proved important. The three stereoisomers of harzianic acid were also prepared, providing material for comparison of their biological activity. While all of the isomers promoted root growth, improved antifungal activity was unexpectedly associated with isomers in the enantiomeric series opposite that of harzianic acid.Publisher PDFPeer reviewe
Tsunamis scenarios in the Adriatic Sea
We calculated the expected impact on the Italian coast of the Adriatic Sea of a large set of tsunamis resulting from potential earthquakes generated by major fault zones. Our approach merges updated knowledge on the regional tectonics and scenario-like calculations of expected tsunami impact.
We selected six elongated potential source zones. For each of them we determined a Maximum Credible Earthquake and the associated Typical Fault, described by its size, geometry and kinematics. We then let the Typical Fault float along strike of its parent source zone and simulated all tsunamis it could generate. Simulations are based on the solution of the nonlinear shallow water equations through a finite-difference technique. For each run we calculated the wave fields at specified simulation times and the maximum water height field (above mean sea level), then generated travel-time maps and maximum wave height profiles along the target coastline. Maxima were also classified in a three-level code of expected tsunami threat.
We found that the southern portion of Apulia facing Albania and the Gargano promontory are especially prone to the tsunami threat. We also found that some bathymetric features are crucial in determining the focalization-defocalization of tsunami energy. We suggest that our results be taken into account in the design of early-warning strategies
Integrating geologic fault data into tsunami hazard studies
We present the realization of a fault-source data set designed to become the starting point in regional-scale tsunami hazard studies. Our approach focuses on the parametric fault characterization in terms of geometry, kinematics, and assessment of activity rates, and includes a systematic classification in six justification levels of epistemic uncertainty related with the existence and behaviour of fault sources. We set up a case study in the central Mediterranean Sea, an area at the intersection of the European, African, and Aegean plates, characterized by a complex and debated tectonic structure and where several tsunamis occurred in the past. Using tsunami scenarios of maximum wave height due to crustal earthquakes (Mw=7) and subduction earthquakes (Mw=7 and Mw=8), we illustrate first-order consequences of critical choices in addressing the seismogenic and tsunamigenic potentials of fault sources. Although tsunamis generated by Mw=8 earthquakes predictably affect the entire basin, the impact of tsunamis generated by Mw=7 earthquakes on either crustal or subduction fault sources can still be strong at many locales. Such scenarios show how the relative location/orientation of faults with respect to target coastlines coupled with bathymetric features suggest avoiding the preselection of fault sources without addressing their possible impact onto hazard analysis results
Patient and public involvement and engagement with underserved communities in dementia research: Reporting on a partnership to co-design a website for postdiagnostic dementia support
\ua9 2024 The Authors. Health Expectations published by John Wiley & Sons Ltd. Introduction: Despite the advancements in Patient and Public Involvement and Engagement (PPIE), the voices of traditionally underserved groups are still poorly reflected in dementia research. This study aimed to report on a PPIE partnership between academics and members of the public from underserved communities to co-design Forward with Dementia—Social Care, a resource and information website supporting people receiving a dementia diagnosis. Methods: The PPIE partnership was set up in four stages: 1–identifying communities that have been under-represented from PPIE in dementia research; 2—recruiting PPIE partners from these communities; 3—supporting PPIE partners to become confident to undertake their research roles and 4—undertaking research co-design activities in an equitable fashion. Results: To address under-representation from PPIE in dementia research we recruited seven PPIE partners from Black, Asian and other minority ethnic groups; lesbian, gay, bisexual, transgender, queer+ communities; remote/rural area; religious minorities and partners living with rare forms of dementia. The partners met regularly throughout the project to oversee new sections for the study website, refine existing content and promote the website within their communities. Conclusion: Strategies can be used to successfully recruit and involve PPIE partners from underserved communities in co-design activities. These include networking with community leaders, developing terms of reference, setting out ‘rules of engagement’, and investing adequate resources and time for accessible and equitable involvement. These efforts facilitate the co-design of research outputs that reflect the diversity and complexity of UK contemporary society. Patient or Public Contribution: This study received support from seven members of the public with lived experience of dementia from communities that have been traditionally underserved in dementia research. These seven members of the public undertook the role of partners in the study. They all equally contributed to the study design, recruitment of participants, development and revision of topic guides for the interviews and development of the website. Three of these partners were also co-authors of this paper. On top of the activities shared with the other partners, they contributed to write independently of the academic team the section in this paper titled ‘Partners\u27 experiences, benefits and challenges of the partnership’. Further, they provided input in other sections of the paper on a par with the other (academic) co-authors
Trichoderma atroviride P1 Colonization of Tomato Plants Enhances Both Direct and Indirect Defense Barriers Against Insects
Numerous microbial root symbionts are known to induce different levels of enhanced plant protection against a variety of pathogens. However, more recent studies have demonstrated that beneficial microbes are able to induce plant systemic resistance that confers some degree of protection against insects. Here, we report how treatments with the fungal biocontrol agent Trichoderma atroviride strain P1 in tomato plants induce responses that affect pest insects with different feeding habits: the noctuid moth Spodoptera littoralis (Boisduval) and the aphid Macrosiphum euphorbiae (Thomas). We observed that the tomato plant–Trichoderma P1 interaction had a negative impact on the development of moth larvae and on aphid longevity. These effects were attributed to a plant response induced by Trichoderma that was associated with transcriptional changes of a wide array of defense-related genes. While the impact on aphids could be related to the up-regulation of genes involved in the oxidative burst reaction, which occur early in the defense reaction, the negative performance of moth larvae was associated with the enhanced expression of genes encoding for protective enzymes (i.e., Proteinase inhibitor I (PI), Threonine deaminase, Leucine aminopeptidase A1, Arginase 2, and Polyphenol oxidase) that are activated downstream in the defense cascade. In addition, Trichoderma P1 produced alterations in plant metabolic pathways leading to the production and release of volatile organic compounds (VOCs) that are involved in the attraction of the aphid parasitoid Aphidius ervi, thus reinforcing the indirect plant defense barriers. Our findings, along with the evidence available in the literature, indicate that the outcome of the tripartite interaction among plant, Trichoderma, and pests is highly specific and only a comprehensive approach, integrating both insect phenotypic changes and plant transcriptomic alterations, can allow a reliable prediction of its potential for plant protectio
Wavelet analysis on paleomagnetic (and computer simulated) VGP time series
We present Continuous Wavelet Transform (CWT) data analysis of Virtual Geomagnetic Pole (VGP) latitude
time series. The analyzed time series are sedimentary paleomagnetic and geodynamo simulated data. Two mother
wavelets (the Morlet function and the first derivative of a Gaussian function) are used in order to detect features
related to the spectral content as well as polarity excursions and reversals. By means of the Morlet wavelet,
we estimate both the global spectrum and the time evolution of the spectral content of the paleomagnetic data
series. Some peaks corresponding to the orbital components are revealed by the spectra and the local analysis
helped disclose their statistical significance. Even if this feature could be an indication of orbital influence on
geodynamo, other interpretations are possible. In particular, we note a correspondence of local spectral peaks
with the appearance of the excursions in the series. The comparison among the paleomagnetic and simulated
spectra shows a similarity in the high frequency region indicating that their degree of regularity is analogous. By
means of Gaussian first derivative wavelet, reversals and excursions of polarity were sought. The analysis was
performed first on the simulated data, to have a guide in understanding the features present in the more complex
paleomagnetic data. Various excursions and reversals have been identified, despite of the prevalent normality of
the series and its inherent noise. The found relative chronology of the paleomagnetic data reversals was compared
with a coeval global polarity time scale (Channel et al., 1995). The relative lengths of polarity stability intervals
are found similar, but a general shift appears between the two scales, that could be due to the datation uncertainties
of the Hauterivian/Barremian boundary
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