92 research outputs found
Thermal Induced Polymerization of l-Lysine forms Branched Particles with Blue Fluorescence
AbstractThe polycondensation of amino acids can originate complex polymers that display fascinating structural and optical properties. Thermally induced amidation of lâlysine allows forming a branched polymer without the support of any catalyst. The polycondensation is completed at 240â250 °C; at higher temperatures, the amino acid degrades. The obtained polylysine particles have been studied by transmission electron microscopy (TEM), nuclear magnetic resonance, and infrared spectroscopy that allow for investigating the different steps of the synthesis. The resulting structure is characterized by peculiar optical properties, e.g., excitationâdependent blue fluorescence and good quantum efficiency. Hydrogen bonds and the interactions of the amino acids are considered responsible for the optical properties of both lâlysine monomer solutions at high concentrations and the branched nanopolymers
Broad distribution and high proportion of protein synthesis active marine bacteria revealed by click chemistry at the single cell level
Microbe-assisted seedling crop improvement by a seaweed extract to address fucalean forest restoration
In the Mediterranean, Cystoseira sensu lato (s.l.) (Phaeophyceae) forests have
sharply declined and restoration measures are needed to compensate for the
loss. Assisted regeneration through the outplanting of seedlings grown ex-situ
has proven to be a sustainable option. Optimizing mesocosm culture can
maximize survival of the most critical embryonic stages and reduce long-term
maintenance costs. Host-microbiome interactions could also play a crucial role
in seedling development and welfare. In this context, we aimed to advance a
cultivation protocol that stimulates the growth and fitness of Ericaria amentacea
(Phaeophyceae) seedlings and identify the associated microbial biofilm
communities. Seedlings were cultured in 6 treatments [i.e., filtered seawater
(SW, C, Control), von Stoch-enriched SW (VS), VS + algal extract (VSA), algal
extract-enriched SW: A1< A2< A3]. After the field, A2 seedlings had the highest
cover (1372 ± 53.66 mm2), which was 1.8 and 1.9 times greater than in VS and
VSA, respectively. The addition of the algal extract and nutrients significantly
affected the structure and composition of the microbial community that shifted
over time in each culture medium. We identified a treatment-specific microbial
fingerprint. After the mesocosm phase, A2 was characterized by 4 unique taxa:
Postechiella, Winogradskyella, Roseovarius and Arenibacter (Bacteria). Given the
success of A2 seedlings, we propose the probiotic consortia candidates
characterized by the unique treatment-taxa in conjunction with the shared
taxon Psychroserpens (Bacteria, present in A1, A2, VSA, VS) and the reminder
community. Within the holobiont concept, the effect of algal extract or nutrients
on the algae and/or biofilm could have important consequences for tuning the
overall interaction networks. Our study has shown that macroalgal restoration
could benefit from both the use of commercial algal extract and tailored nutrient
enrichment in ex-situ cultures and the identification of probiotic consortia
candidates that promote seedling growth
Patient-Reported Outcomes After Swallowing (SWOARs)-Sparing IMRT in Head and Neck Cancers: Primary Results from a Prospective Study Endorsed by the Head and Neck Study Group (HNSG) of the Italian Association of Radiotherapy and Clinical Oncology (AIRO)
Objectives To prospectively investigate changes in M.D. Anderson Dysphagia Inventory (MDADI) scores in patients affected by naso- and oropharynx cancer after definitive radiochemotherapy (ChemoRT) using swallowing organs at risk (SWOARs)-sparing IMRT. Methods MDADI questionnaires were collected at baseline and at 6 and 12 months after treatment. MDADI scores were categorized as follows: >= 80 "optimal," 80-60 "adequate," < 60 "poor" deglutition-related quality of life (QoL) group, and dichotomized as "optimal" vs "adequate/poor" for the analysis. A mean MDADI composite (MDADI-C) change of 10 points was considered as minimal clinically important difference (MCID). Results Sixty-three patients were enrolled of which 47 were considered for the analysis. At baseline, 26 (55%) were "optimal" and 21 (45%) were "adequate/poor." The mean baseline MDADI-C score was 93.6 dropping to 81 at 6 months (p = 0.013) and slightly rising to 85.5 at 12 months (p = 0.321) for the "optimal" group. Indeed, the mean baseline MDADI-C score was 64.3 rising to 77.5 at 6 months (p = 0.006) and stabilizing at 76 at 12 months (p = 0.999) for the "adequate/poor" group. A statistically significant but not clinically relevant worsening of the MDADI-C score was reported for the "optimal" group, whereas both a statistically significant and clinically meaningful improvement of the MDADI-C score were reported for the "adequate/poor" group from before to post-treatment. Conclusion Our results suggest a doubly clinical benefit of dose optimization to SWOARs to minimize the RT sequalae in patients with a baseline "optimal" deglutition-related QoL and to recover from cancer dysphagia in those with a baseline "adequate/poor" deglutition-related QoL
Abasic and oxidized ribonucleotides embedded in DNA are processed by human APE1 and not by RNase H2
Ribonucleoside 5'-monophosphates (rNMPs) are the most common non-standard nucleotides found in DNA of eukaryotic cells, with over 100 million rNMPs transiently incorporated in the mammalian genome per cell cycle. Human ribonuclease (RNase) H2 is the principal enzyme able to cleave rNMPs in DNA. Whether RNase H2 may process abasic or oxidized rNMPs incorporated in DNA is unknown. The base excision repair (BER) pathway is mainly responsible for repairing oxidized and abasic sites into DNA. Here we show that human RNase H2 is unable to process an abasic rNMP (rAP site) or a ribose 8oxoG (r8oxoG) site embedded in DNA. On the contrary, we found that recombinant purified human apurinic/apyrimidinic endonuclease-1 (APE1) and APE1 from human cell extracts efficiently process an rAP site in DNA and have weak endoribonuclease and 3'-exonuclease activities on r8oxoG substrate. Using biochemical assays, our results provide evidence of a human enzyme able to recognize and process abasic and oxidized ribonucleotides embedded in DNA
Defect-assisted photoluminescence in hexagonal boron nitride nanosheets
The development of functional optoelectronic applications based on hexagonal boron nitride nanosheets (h-BNNs) relies on controlling the structural defects. The fluorescent emission, in particular, has been observed to depend on vacancies and substitutional defects. In the present work, few-layerh-BNNs have been obtained by sonication-assisted liquid-phase exfoliation of their bulk counterpart. The as-prepared samples exhibit a weak fluorescent emission in the visible range, centred around 400 nm. Tailored defects have been introduced by oxidation in air at different temperatures. A significant increase in the fluorescent emission of the oxidatedh-BNNs has been observed with maximum emissive intensity for the samples treated at 300 degrees C. A further increase in temperatures (>300 degrees C) determines a quenching of the fluorescence. We investigated, by means of detailed microscopic and spectroscopic analysis, the relationship between the optical properties and defects ofh-BNNs. The investigation of the optical properties as a function of treatment temperature highlights the critical role of hydroxyl groups created by the oxidation process. Onlyh-BN exfoliated in water allows introducing OH groups with consequent enhancement of fluorescence emission. Quantum chemical calculations support the experimental findings
A Conceptual Framework for Developing the Next Generation of Marine OBservatories (MOBs) for Science and Society
In the field of ocean observing, the term of âobservatoryâ is often used without a unique meaning. A clear and unified definition of observatory is needed in order to facilitate the communication in a multidisciplinary community, to capitalize on future technological innovations and to support the observatory design based on societal needs. In this paper, we present a general framework to define the next generation Marine OBservatory (MOB), its capabilities and functionalities in an operational context. The MOB consists of four interconnected components or âgearsâ (observation infrastructure, cyberinfrastructure, support capacity, and knowledge generation engine) that are constantly and adaptively interacting with each other. Therefore, a MOB is a complex infrastructure focused on a specific geographic area with the primary scope to generate knowledge via data synthesis and thereby addressing scientific, societal, or economic challenges. Long-term sustainability is a key MOB feature that should be guaranteed through an appropriate governance. MOBs should be open to innovations and good practices to reduce operational costs and to allow their development in quality and quantity. A deeper biological understanding of the marine ecosystem should be reached with the proliferation of MOBs, thus contributing to effective conservation of ecosystems and management of human activities in the oceans. We provide an actionable model for the upgrade and development of sustained marine observatories producing knowledge to support science-based economic and societal decisions
Marine Citizen Science: Current State in Europe and New Technological Developments
Marine citizen science is emerging with promising opportunities for science, policy and
public but there is still no comprehensive overview of the current state in Europe.
Based on 127 projects identified for the North Sea area we estimate there might be
as much as 500 marine and coastal citizen science projects running in Europe, i.e.,
one marine citizen science project per 85 km of coastline, with an exponential growth
since 1990. Beach-based projects are more accessible and hence most popular (60%
of the projects), and the mean duration of the projects is 18â20 years. Current trends,
topics, organizers, aims, and types of programme in terms of participation are presented
in this overview. Progress in marine citizen science is specially enabled and promoted
through technological developments. Recent technological advances and best practise
examples are provided here, untapping the potential of smart mobile apps, do-it-yourself
(DIY) technologies, drones, and artificial intelligence (AI) web servicesVersiĂłn del edito
Taxon-Specific Aerosolization of Bacteria and Viruses In an Experimental Ocean-Atmosphere Mesocosm
Ocean-derived, airborne microbes play important roles in Earthâs climate system and human health, yet little is known about factors controlling their transfer from the ocean to the atmosphere. Here, we study microbiomes of isolated sea spray aerosol (SSA) collected in a unique oceanâatmosphere facility and demonstrate taxon-specific aerosolization of bacteria and viruses. These trends are conserved within taxonomic orders and classes, and temporal variation in aerosolization is similarly shared by related taxa. We observe enhanced transfer into SSA of Actinobacteria, certain Gammaproteobacteria, and lipid-enveloped viruses; conversely, Flavobacteriia, some Alphaproteobacteria, and Caudovirales are generally under-represented in SSA. Viruses do not transfer to SSA as efficiently as bacteria. The enrichment of mycolic acid-coated Corynebacteriales and lipid-enveloped viruses (inferred from genomic comparisons) suggests that hydrophobic properties increase transport to the sea surface and SSA. Our results identify taxa relevant to atmospheric processes and a framework to further elucidate aerosolization mechanisms influencing microbial and viral transport pathways
Navigating the Future V: Marine Science for a Sustainable Future
Navigating the Future is a publication series produced by the European Marine Board providing future
perspectives on marine science and technology in Europe. Navigating the Future V (NFV) highlights new
knowledge obtained since Navigating the Future IV1 (2013). It is set within the framework of the 2015
Paris Agreement2 and builds on the scientific basis and recommendations of the IPCC reports3. NFV gives
recommendations on the science required during the next decade to deliver the ocean we need to support
a sustainable future. This will be important for the United Nations Decade of Ocean Science for Sustainable
Development4 (2021 â 2030), the implementation of the UN Sustainable Development Goals5 and the
European Commissionâs next framework programme, Horizon Europe6 (2021 - 2027). There is a growing need
to strengthen the links between marine science, society and policy since we cannot properly manage what
we do not know.
In recent years, the ocean and seas have received new prominence in international agendas. To secure a
safe planet a priority is the management of the ocean as a âcommon good for humanityâ, which requires
smarter observations to assess of the state of the ocean and predictions about how it may change in the
future. The ocean is a three-dimensional space that needs to be managed over time (thus four-dimensional),
and there is a need for management and conservation practices that integrate the structure and function
of marine ecosystems into these four dimensions (Chapter 2). This includes understanding the dynamic
spatial and temporal interplay between ocean physics, chemistry and biology. Multiple stressors including
climate change, pollution and over-fishing affect the ocean and we need to better understand and predict
their interactions and identify tipping points to decide on management priorities (Chapter 3). This should
integrate our understanding of land-ocean-atmosphere processes and approaches to reducing impacts. An
improved science base is also needed to help predict and minimize the impact of extreme events such as
storm surges, heat waves, dynamic sea-floor processes and tsunamis (Chapter 4). New technologies, data
handling and modelling approaches will help us to observe, understand and manage our use of the fourdimensional
ocean and the effect of multiple stressors (Chapter 5).
Addressing these issues requires a strategic, collective and holistic approach and we need to build a
community of sustainability scientists that are able to provide evidence-based support to policy makers
within the context of major societal challenges (Chapter 6). We outline new frontiers, knowledge gaps and
recommendations needed to manage the ocean as a common good and to develop solutions for a sustainable
future (Chapter 7). The governance of sustainability should be at the core of the marine research agenda
through co-production and collaboration with stakeholders to identify priorities. There is need for a fully
integrated scientific assessment of resilience strategies, associated trade-offs and underlying ethical concepts
for the ocean, which should be incorporated into decision support frameworks that involve stakeholders from
the outset. To allow the collection, processing and access to all data, a key priority is the development of a
business model that ensures the long-term economic sustainability of ocean observations
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