1,354,588 research outputs found
PLoS One 2024 Cazzolla A et al
No full textDatasets for PLoS One Manuscript: "Synthesis of cationic liposome nanoparticles using a thin film dispersed hydration and extrusion method" by Alessandro Cazzolla et al (2024
Estimating and comparing biodiversity with a single universal metric
No full textThe development of a unique index to represent the real diversity of a community is still a challenge. The difficulties to find a single, reliable, diversity metric is mostly due to the fact that the indices allowing an estimation of the number of species actually present in a sample do not provide information on how species abundances are distributed within a community. Although some diversity measures attempted to weigh richness in relation to the total abundance, the homogeneity (evenness) of individuals within species is not integrated into them. The most common diversity indices have been "summarized" by Hill in 1973 in a single equation and, subsequently, different indicators have been proposed to estimate the "absolute" and the “effective” number of species present in a study area in an attempt to find a unified treatment of all standard diversity indices and to compare the true diversity among community. However, the choice of one of the effective number of species indices depends on what aspects of diversity of the study sites the research aims to investigate and could bias the study and mislead the interpretation of the comparative results. Moreover, effective Hill numbers account for only the observed, and not the expected (i.e. the absolute) diversity of the studied community. To compare and interpret the effective number of species with one single metric and analyze the diversity data with techniques that do not depend on a traditional non-parametric index, we developed an absolute measure of diversity based on the effective number of species and derived from the Hill numbers of order 0, 1, and 2. We tested the new index against previously-proposed absolute diversity estimators and the first three Hill numbers taken alone. We simulated the new index's behavior with different gradients of richness, abundance and evenness and we, finally, empirically tested it on tree communities of three biomes (boreal, temperate and tropical forests) of the United States and on a coral reef community of Cuba. This new index proved to be the first reliable and comparable measure, which combines both the absolute richness and the evenness of a community related to the most used traditional indices in a unique, simple and comprehensive numerical value that would represent the absolute effective diversity (AED) of any biological community
Taranto’s Long Shadow? Cancer Mortality Is Higher for People Living Closer to One of the Most Polluted City of Italy
No full textA national-scale study in Italy showed an incidence of cancer higher in the territories indicated as highly polluted compared to the regional average. One of them, the city of Taranto in Apulia (Italy), which is considered one of the most polluted cities in Europe, has numerous industrial activities that impact population health. We studied the epidemiological effects of a high level of pollution produced by the industrial area of Taranto in increasing the mortality rate for some specific cancer types in the city and towns of the two provinces located downwind. We analysed 10-year mortality rates for 15 major types of tumours reported among the residents of Taranto, of eight surrounding towns, randomly placed within an imaginary cone in the main wind direction from the vertex of the industrial zone of Taranto, and of the two related provinces (Bari and Taranto’s metropolitan areas). Our results confirm our hypothesis that the mortality rate for some specific types of cancer is higher than the norm in the municipality of Taranto. We also found strong evidence that, for 12 out of 15 tumour types, mortality decreases with the distance of the other towns from Taranto’s industrial site. However, we have reasons to believe that other local causes may be implicated in the excess of mortality in some specific municipalities besides the potential dispersal of pollutants from the industrial area of Taranto. The proximity to Taranto cannot, in fact, explain all the anomalies detected in some populations. It is likely that other site-specific sources of heavy pollution are playing a role in worsening the death toll of these towns and this must be taken into serious consideration by environmental policymakers and local authorities
Certified “sustainable” palm oil took the place of endangered Bornean and Sumatran large mammals habitat and tropical forests in the last 30 years
No full textTropical forests inhabited by endangered orangutans, rhinos, tigers, and elephants in South-east Asia are threatened by deforestation, including oil palm expansion. Certification has been proposed to label sustainable palm oil production. However, from a remotely sensed time-series and imagery analysis (1984–2020), we discovered that most of the currently certified grower supply bases and concessions in Sumatra and Borneo are located in the 1990s large mammals habitat and in areas that were biodiverse tropical forests less than 30 years ago. In light of this dramatic evidence, we suggest that certification schemes claim for the “sustainable” production of palm oil just because they neglect a very recent past of deforestation and habitat degradation
A century of biodiversity: some open questions and some answers
No full textThe study the biodiversity is not just an attempt to understand the differences or similarities between species, habitats or genomes. It also includes an understanding of how nature regulates the processes that characterise ecosystems and ensure their functionality. It means as well to increase the ability to predict the impact of current and future anthropogenic actions on nature (Midgley et al. 2002). Biodiversity is what makes the Earth a unique planet. In the Universe, for all we know, or at least in our galaxy, life is the exception rather than the rule (Dick 1999). And even if a day when we are able to document the presence of living beings on other planets will come, this will also be an exception. The appearance of life is a phenomenon that has always fascinated mankind since without it, our human species would have never existed and no hairless biped would have studied life, with great admiration, and destroyed it with equal force (Cardinale et al. 2012)
The pangolin's revenge: SARS-CoV-2 did not emerge from a lab but from wildlife exploitation
No full textIn recent weeks, news has spread that the current coronavirus is the result of something created in a laboratory that then escaped control. This concern also stems from news reporting that back in 2015 experiments were already being carried out in China to create a recombinant SARS-derived coronavirus. Unfortunately, such news finds fertile ground on social media and, especially in pandemic periods, fosters conspiracies and paranoia. This time, however, the news was spread by some authoritative sources. Here I explain how I found out convincing evidence that SARS-CoV-2 did not emerge from a lab but from wildlife exploitation
Climate change-induced salinity variation impacts on a stenoecious mangrove species in the Indian Sundarbans
No full textThe alterations in the salinity profile are an indirect, but potentially sensitive, indicator for detecting changes in precipitation, evaporation, river run-off, glacier retreat, and ice melt. These changes have a high impact on the growth of coastal plant species, such as mangroves. Here, we present estimates of the variability of salinity and the biomass of a stenoecious mangrove species (Heritiera fomes, commonly referred to as Sundari) in the aquatic subsystem of the lower Gangetic delta based on a dataset from 2004 to 2015. We highlight the impact of salinity alteration on the change in aboveground biomass of this endangered species that, due to different salinity profile in the western and central sectors of the lower Gangetic plain, shows an increase only in the former sector, where the salinity is dropping and low growth in the latter, where the salinity is increasing
A multi-armed bandit algorithm speeds up the evolution of cooperation
No full textMost evolutionary biologists consider selfishness an intrinsic feature of our genes and as the best choice in social situations. During the last years, prolific research has been conducted on the mechanisms that can allow cooperation to emerge “in a world of defectors” to become an evolutionarily stable strategy. A big debate started with the proposal by W.D. Hamilton of “kin selection” in terms of cost sustained by the cooperators and benefits received by related conspecifics. After this, four other main rules for the evolution of cooperation have been suggested. However, one of the main problems of these five rules is the assumption that the payoffs obtained by either cooperating or defeating are quite well known by the parties before they interact and do not change during the time or after repeated encounters. This is not always the case in real life. Following each rule blindly, there is a risk for individuals to get stuck in an unfavorable situation. Axelrod (1984) highlighted that the main problem is how to obtain benefits from cooperation without passing through several trials and errors, which are slow and painful. With a better understanding of this process, individuals can use their foresight to speed up the evolution of cooperation. Here I show that a multi-armed bandit (MAB) model, a classic problem in decision sciences, is naturally employed by individuals to opt for the best choice most of the time, accelerating the evolution of the altruistic behavior and solving the abovementioned problems. A common MAB model that applies extremely well to the evolution of cooperation is the epsilon-greedy (ε-greedy) algorithm. This algorithm, after an initial period of exploration (which can be considered as biological history), greedily exploits the best option ε% of the time and explores other options the remaining percentage of times (1-ε%). Through the epsilon-greedy decision-making algorithm, cooperation evolves as a multilevel process nested in the hierarchical levels that exist among the five rules for the evolution of cooperation. This reinforcement learning, a subtype of artificial intelligence, with trials and errors, provides a powerful tool to better understand and even probabilistically quantify the chances cooperation has to evolve in a specific situation
Omalizumab for the Treatment of Chronic Spontaneous Urticaria: Association Between Body Mass Index and Outcome
No full textINTRODUCTION: Omalizumab has been recently registered as a third-line therapy for chronic spontaneous urticaria. OBJECTIVES: In this study, we aimed to provide real life data by reporting our experience with omalizumab in the treatment of chronic spontaneous urticaria. METHODS: A retrospective data analysis was conducted on 40 patients affected by chronic spontaneous urticaria and treated with omalizumab at the Dermatology Unit of Padua. Demographic, anthropometric, and clinical data have been collected. RESULTS: Overall, the majority of patients (23 patients, 57.5%) achieved complete recovery by taking omalizumab and 17.5% (7 patients) had a partial response. The majority of patients who did not have a response to omalizumab had a body mass index (BMI) > 25 kg/m(2). CONCLUSIONS: Our study suggests that omalizumab is a safe and effective treatment for chronic spontaneous urticaria. We identified BMI as a critical biological factor that significantly impacts the outcomes of omalizumab treatment. Our findings also suggest a potential use of BMI as a predictive biomarker for omalizumab treatment. An up-dosing of omalizumab may be proposed in patients with high BMI to achieve a better control of the disease
Clarifying the smokescreen of Russian protected areas
No full textAlthough in strictly protected areas no forest management and logging activities should be evident, a preliminary study detected that, even in the 200 areas with the highest protection of Russia, more than 2 Mha of trees have been lost between 2001 and 2018. Nonetheless, a relevant percentage of the actual drivers of tree loss in Russian strictly protected areas was surrounded by uncertainties due to several factors. Here, in an attempt to “clarify the smokescreen of Russian protected areas”, by validating previous remotely sensed data with new high-resolution satellite imagery and aerial images of land-use change, we shed more light on what has happened during the last 20 years. We used the same layer of tree loss from 2001 to 2020 but, instead of intersecting it with the MODIS data that could have been a source of underestimation of burned surfaces, we overlapped it to the layer of tree cover loss by dominant driver. We analysed the main drivers of tree loss in almost 200 strictly protected areas of Russia. We found that although fire is responsible for 75% of the loss in all strictly protected areas, forestry activities still account for 16%, and 9% is due to undefined causes. Therefore, uncontrolled wildfires (including those started before or after logging) and forestry activities are the main causes of 91% of the total tree loss. The combination of wildfires (often started intentionally) and forestry activities (illegally or barely legally put in place) caused a loss of an astonishing 3 million hectares. The fact that ≈10% of Russian tree cover was lost in two decades since 2001 only in strictly protected areas requires high attention by policymakers and important conservation actions to avoid losing other fundamental habitats and species during the next years when climate change and population growth can represent an additional trigger of an already dramatic situation. We call for an urgent response by national and local authorities that should start actively fighting wildfires, arsonists, and loggers even in inhabited remote areas and particularly in those included in strictly protected areas
- …
