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Question: In the fall 2018 we observed an atypical pattern with concentric belts of green, yellow, and brown vegetation. What are the causes of the pattern? Localized water depletion, soil spatial heterogeneity and the activity of pathogenic organisms were tested as alternative hypotheses. Location: Banks of a water reservoir, Alento basin in south Italy (40°19′04.50″ N; 15°06′45.35″ E). Methods: Belts were monitored for floristic composition and plant health status. In each zone, 17 soil parameters were analysed (soil texture, pH, electrical conductivity, limestone content, organic C, Olsen P, total N, C/N ratio, cations exchange capacity, Ca2+, Mg2+, Na+, K+, Fe, Cu, Zn, Mn). Soil moisture was monitored by soil probes, positioned at 10cm depth. The incidence of pathogens and parasitic plants was visually estimated. Finally, model simulations were carried out to explore the interactions between biotic and abiotic factors in the formation of the belts. Results: The vegetation survey revealed that the green belt was characterized by a monospecific stand of Xanthium italicum with a plant density >190 individuals per m2. All plants were healthy. In the yellow belt, instead, Xanthium italicum was attacked by the parasitic plant Cuscuta campestris with an incidence >70%. In the brown belt all Xanthium italicum was still standing but dead, with an incidence of Cuscuta campestris attack >94%. No differences in soil chemistry were recorded in the three belts, while soil moisture was slightly lower in the green belt, likely as a result of a higher evapotranspiration rate. The modelling simulation well reproduced the banded vegetation, supporting the role of the parasitic plant in the formation of the pattern. Conclusions: By combining extensive field measurements with detailed modelling work, we revealed, for the first time, the primary role of a parasitic plant in the formation of a regular and ephemeral vegetation pattern.

The shallow part of the subsoil, either natural as well as urban or industrial, is impacted by a large number of interactions and interferences on a daily basis, worldwide, because of anthropogenic activities. Excavations, trenching and digging for building constructions, road maintenance, archaeological, urban development, forensic, cavity search, ore bodies search, geological, geotechnical and engineering purposes are conducted every day all over the world. The a-priori knowledge of the subsoil is often poor or non-existing, hence the need for (non-destructive) techniques for the enhancement of the model of the soil, prior to excavation. There are several geophysical techniques whose deployment aims at defining such models, and many of them, for their implementation on site, makes use of sensors to be coupled with the soil (embedded, like geophones for seismic refraction and reflection, or electrodes for Electrical resistivity methods). One of the main advantages of the whole family of the Electromagnetic (EM) methods is because they do not make use of any embedded sensor, fixed on top of the soil surface. This makes the technique fast, non-destructive, and highly productive from the data acquisition point of view. The applicability of the "EM family" methods is rather wide, and ranges from utility mapping, to cavity detection, pollutants search, UXO search, Volcanogenic Massive Sulphides (VMS) search, geotechnical engineering applications and so on. The dimension of the areas that can be covered varies from a few squared meters, for detailed studies with high resolution, to thousands of squared meters for exploration that can reach down to hundreds of meters in depth (for Airborne EM Techniques) for the search of targets of a larger size. Electromagnetic Methods in Geophysics: Theory and Applications provides a general introduction to the electromagnetic methods in several application fields. Physical and mathematical principles and fields of applications are well-explained, and the field acquisition procedures, data processing and interpretation, are illustrated to guarantee the best understanding of the results, on a layman perspective.

In this paper a semi-physical model for the vegetation burning in wildland fire is proposed. The model is developed with the final aim to simulate large scale wildland fires which spread on heterogeneous landscape. In a modular modelling approach, it can be seen as the cell model for a forest fire propagation tool to perform fast simulations for operational scope and fight fires interventions. It is constituted by a simple system of ordinary differential equations taking into account the main physico-chemical processes involved in the fire spreading while keeping the computation cost for simulations very low. Finally, the model is implemented in the modelling, at the intermediate scale (1 hectare), of the fire spreading in a homogeneous environment.

For some time a debate has been promoted both in scientific journals andin the press about the quality of the Italian University system. On the one hand,some authors claim that in Italy we do too little research, leading to a waste ofpublic money. On the other hand, others claim that Italy is basically similar toother comparable countries.This paper aims at presenting some indicators which will help the readers tobetter understand the effectiveness - for each euro spent - of the Italian universitysystem in the international scenario, using the OECD (Organization for EconomicCooperation and Development) and WOS (Web of Science) data sets.

We propose an Adaptable Learning System named SIRMM (Searchable Information Repository of Mathematical Models), whose goal is to be an user friendly and easy to use educational environment, in which mathematics can be learned moving from real world applications; on the other way around, SIRMM can allow to deal with technical disciplines such as chemistry, engineering or economics from the mathematical modeling point of view. Finally, SIRMM can be viewed as an user friendly problem solving environment.

Vegetation is continuously changing in time and space. The changes may be autogenic, driven by the properties of the component plant species, or allogenic, driven by external factors. Allogenic change may be a result of gradual changes in environment, but more often results from disturbance events, and the way vegetation responds will be very dependent upon the disturbance history (Miles, 1979). The term disturbance is used in ecology to refer to the partial or complete reduction of biomass due to some external factors and does not include natural mortality or decay processes. Typical causes of disturbance are grazing, cutting, fire, and frost. Disturbance can also be defined as an event that causes a significant change from the normal pattern in an ecological system (Forman and Godron, 1986), but the problem with this relative definition of disturbance stems from the difficulty of defining the “normal” range of conditions for an ecosystem (White and Harrod, 1997). This is why an absolute definition requiring measures of real change is more appropriate for a mechanistic modelling approach. This was the option made by Waring and Running (1998), for example, who defined disturbance in a forest as any factor that brings about a significant reduction in the overstory leaf area index for a period of more than one year. Grubb (1985) reviewed the concept of disturbance and distinguished vegetation resilience 'in situ' and 'by migration' (Grubb and Hopkins, 1986), referring to the regeneration capacity of surviving individuals in the disturbed area and recolonisation from neighbouring areas respectively. In the simplest case of one type of disturbance on a homogeneous site the disturbance regime can be generally described by its frequency and its intensity. However, if intensity is associated with biomass accumulated, as in the case of fire, there is an inverse relationship between intensity and frequency. These considerations were very well established for fire regimes in North America (see for instance Heinselman 1978) and in Europe (e.g. Angelstam 1997). Therefore the simplest way to describe a fire regime is to determine the average time between disturbances (years) or conversely, the mean frequency of the disturbance (expressed in year –1). This paper focuses only on fire and grazing. Henderson and Keit (2002) performed a canonical correspondence analysis on the sources of variation in shrub composition of eucalypt forests which showed that fire and grazing accounted for more variation than the combination of all other environmental and spatial variables. Although they are perhaps the two most important sources of disturbance, they differ very much in character; the former causes an abrupt discontinuity in the system while the latter is characterised by a gradual and continuous process of selective biomass removal.

Aim: Fungal ‘fairy rings’ (FRs) are regular bands of vegetation caused by a centrifugal expansion of fungal mycelia. It is well established that FR fungi affect both soil chemistry and microbiome, but nothing is known about the distribution of these patterns at the regional scale. Here, we assess the abundance and occurrences of different FR shapes i.e. rings, arcs and rotors, and explore their association with geomorphology and climate. Location: The Apennine Mountains, 300-km latitudinal gradient along the Italian Peninsula. Taxon: Basidiomycetous fungi. Methods: High-resolution freely available images were gathered to study FR shapes and distribution in the Apennine region of Italy. First, 12 mountains with different elevations and geomorphology were studied to assess the colonial density and relative distribution of FR type. FR distribution and shape and size of additional 616 FRs were studied in 61 study sites and relationship with selected climatic and topographic variables were assessed using different modelling approaches. Results: Overall, 1163 FR structures were found across the study area. Arcs were the most common shape followed by rings. Rotors were rare, accounting for less than 2% of all observations. Fungal colony density varied largely both among and within sites, averaging 6.7 arcs, 2.2 rings and only 0.1 rotors per ha. On average, arcs (18.8 m) were similar in size compared to rotors (18.4 m) whilst rings were smaller (11.7 m). Arcs presented a higher frequency of occurrence on steeper slopes whilst rings were mostly found on flat and moderate slopes. FRs occurred within the altitudinal range between 546 m and 2148 m a.s.l., corresponding to temperatures between 3.4 and 12.7°C and rainfall between 1100 and 1300 mm per year. Main Conclusions: FRs are common elements of the Apennine grassland landscape where they may contribute to the maintenance of plant and microbial diversity. Better systematic identification of the fungal species involved in the formation of FRs is required. Further research that combines long-term field manipulative experiments and modelling work would help to explain the formation of rings, arcs and rotors during the ontogenetic development of fungal fronts.

In this paper, a compartmental mathematical model has been utilized to gain a better insight about the future dynamics of COVID-19. The total human population is divided into eight various compartments including susceptible, exposed, pre-asymptomatic, asymptomatic, symptomatic, quarantined, hospitalized and recovered or removed individuals. The problem was modeled in terms of highly nonlinear coupled system of classical order ordinary differential equations (ODEs) which was further generalized with the Atangana-Balaeanu (ABC) fractional derivative in Caputo sense with nonlocal kernel. Furthermore, some theoretical analyses have been done such as boundedness, positivity, existence and uniqueness of the considered. Disease-free and endemic equilibrium points were also assessed. The basic reproduction was calculated through next generation technique. Due to high risk of infection, in the present study, we have considered the reported cases from three continents namely Americas, Europe, and south-east Asia. The reported cases were considered between 1st May 2021 and 31st July 2021 and on the basis of this data, the spread of infection is predicted for the next 200 days. The graphical solution of the considered nonlinear fractional model was obtained via numerical scheme by implementing the MATLAB software. Based on the fitted values of parameters, the basic reproduction number ℜ0 for the case of America, Asia and Europe were calculated as ℜ0≈2.92819, ℜ0≈2.87970 and ℜ0≈2.23507 respectively. It is also observed that the spread of infection in America is comparatively high followed by Asia and Europe. Moreover, the effect of fractional parameter is shown on the dynamics of spread of infection among different classes. Additionally, the effect of quarantined and treatment of infected individuals is also shown graphically. From the present analysis it is observed that awareness of being quarantine and proper treatment can reduce the infection rate dramatically and a minimal variation in quarantine and treatment rates of infected individuals can lead us to decrease the rate of infection.

Single-cell technology is a relatively new and promising way to obtain high-resolution transcriptomic data mostly used for animals during the last decade. However, several scientific groups developed and applied the protocols for some plant tissues. Together with deeply-developed cell-resolution imaging techniques, this achievement opens up new horizons for studying the complex mechanisms of plant tissue architecture formation. While the opportunities for integrating data from transcriptomic to morphogenetic levels in a unified system still present several difficulties, plant tissues have some additional peculiarities. One of the plants’ features is that cell-to-cell communication topology through plasmodesmata forms during tissue growth and morphogenesis and results in mutual regulation of expression between neighboring cells affecting internal processes and cell domain development. Undoubtedly, we must take this fact into account when analyzing single-cell transcriptomic data. Cell-based computational modeling approaches successfully used in plant morphogenesis studies promise to be an efficient way to summarize such novel multiscale data. The inverse problem’s solutions for these models computed on the real tissue templates can shed light on the restoration of individual cells’ spatial localization in the initial plant organ—one of the most ambiguous and challenging stages in single-cell transcriptomic data analysis. This review summarizes new opportunities for advanced plant morphogenesis models, which become possible thanks to single-cell transcriptome data. Besides, we show the prospects of microscopy and cell-resolution imaging techniques to solve several spatial problems in single-cell transcriptomic data analysis and enhance the hybrid modeling framework opportunities.

We address a mathematical model to approximate in a coarse qualitative the interaction between inbreeding-lobbying and interdisciplinarity in academia and perform a one and two-parameter numerical bifurcation analysis to analyse its dynamics. Disciplinary diversity is a necessary condition for the development of interdisciplinarity, which is being recognized today as the key to establish a vibrant academic environment with bigger potential for breakthroughs/innovation in research and technology. However, the interaction of several factors including institutional policies, and behavioural attitudes put significant barriers on advancing interdisciplinarity. A “cognitive rigidity” may rise due to reactive academic lobby behaviours favouring inbreeding. The proposed model consists of four coupled non-linear Ordinary Differential Equations simulating the interaction between certain types of academic behaviour and the rate of knowledge advancement which is related to the level of disciplinary diversity. The effect of a control policy that inhibits inbreeding-lobbying is also investigated. The numerical bifurcation analysis reveals a rich nonlinear behaviour including multistability, sustained oscillations, limit points of limit cycles, homoclinic bifurcations as well as codimension-two bifurcations and in particular Bogdanov–Takens and Bautin bifurcations.

The regular configuration of fungal basidiomycetous fronts in fairy rings allows a thorough scrutiny of associated soil changes. Here, we studied the soil chemistry and the microbiota modifications induced by the passage of Calocybe gambosa fairy rings in a botanical garden. Significant changes in soil physicochemical properties and microbiota were observed in correspondence of active fungal mycelium, where an accumulation of nutrients, an increase in hydrophobicity, and a decrease in pH were recorded. In addition, on one hand, a sharp decline of fungal diversity in soil occurred in association with C. gambosa colonization. On the other hand, the bacterial community showed a variable taxon-specific response, with taxa within Bacteroidetes and Proteobacteria being able to thrive in association with C. gambosa.

The metabolic shift between respiration and fermentation at high glucose concentration is a widespread phenomenon in microbial world, and it is relevant for the biotechnological exploitation of microbial cell factories, affecting the achievement of high-cell-densities in bioreactors. Starting from a model already developed for the yeast Saccharomyces cerevisiae, based on the System Dynamics approach, a general process-based model for two prokaryotic species of biotechnological interest, such as Escherichia coli and Bacillus subtilis, is proposed. The model is based on the main assumption that glycolytic intermediates act as central catabolic hub regulating the shift between respiratory and fermentative pathways. Furthermore, the description of a mixed fermentation with secondary by-products, characteristic of bacterial metabolism, is explicitly considered. The model also represents the inhibitory effect on growth and metabolism of self-produced toxic compounds relevant in assessing the late phases of high-cell density culture. Model simulations reproduced data from experiments reported in the literature with different strains of non-recombinant and recombinant E. coli and B. subtilis cultured in both batch and fed-batch reactors. The proposed model, based on simple biological assumptions, is able to describe the main dynamics of two microbial species of relevant biotechnological interest. It demonstrates that a reductionist System Dynamics approach to formulate simplified macro-kinetic models can provide a robust representation of cell growth and accumulation in the medium of fermentation by-products.

Question: In the fall 2018 we observed an atypical pattern with concentric belts of green, yellow, and brown vegetation. What are the causes of the pattern? Localized water depletion, soil spatial heterogeneity and the activity of pathogenic organisms were tested as alternative hypotheses. Location: Banks of a water reservoir, Alento basin in south Italy (40°19′04.50″ N; 15°06′45.35″ E). Methods: Belts were monitored for floristic composition and plant health status. In each zone, 17 soil parameters were analysed (soil texture, pH, electrical conductivity, limestone content, organic C, Olsen P, total N, C/N ratio, cations exchange capacity, Ca2+, Mg2+, Na+, K+, Fe, Cu, Zn, Mn). Soil moisture was monitored by soil probes, positioned at 10 cm depth. The incidence of pathogens and parasitic plants was visually estimated. Finally, model simulations were carried out to explore the interactions between biotic and abiotic factors in the formation of the belts. Results: The vegetation survey revealed that the green belt was characterized by a monospecific stand of Xanthium italicum with a plant density >190 individuals per m2. All plants were healthy. In the yellow belt, instead, Xanthium italicum was attacked by the parasitic plant Cuscuta campestris with an incidence >70%. In the brown belt all Xanthium italicum was still standing but dead, with an incidence of Cuscuta campestris attack >94%. No differences in soil chemistry were recorded in the three belts, while soil moisture was slightly lower in the green belt, likely as a result of a higher evapotranspiration rate. The modelling simulation well reproduced the banded vegetation, supporting the role of the parasitic plant in the formation of the pattern. Conclusions: By combining extensive field measurements with detailed modelling work, we revealed, for the first time, the primary role of a parasitic plant in the formation of a regular and ephemeral vegetation pattern.

37th European Photovoltaic Solar Energy Conference and Exhibition; 1972-1974, This paper introduces a recently initiated Italian national project on high innovative PV greenhouses considering different scales of experimentation as well as an interdisciplinary approach involving experts in different areas. At small scale, the light transmittance of spectrally selective solar cells devices, which focus different wavelengths on PV modules and plants, will be analyzed in order to obtain the best compromise between electricity production and photosynthesis. At medium and large scale, two greenhouses will be tested: (i) An experimental greenhouse (about 15 m2) equipped with different IoT sensors and innovative PV glasses technologies will monitor the growing environment together the energy production. (ii) Based on the results obtained in the medium scale greenhouse, some PV glasses will be used as envelope material for the renovation of a commercial-size greenhouse (about 100 m2). Both PV greenhouses will be located in a historic environment dating back to the XVIII century, the Botanical garden of Portici, which requires a careful approach to a correct integration with the landscape. Along the two years of the duration of the project is foreseen to finding the best compromise between functional characteristics (energy and food) and aesthetic ones, thus optimizing the integrated system showing the potential of innovative glasses for greenhouses.