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Riparian field elm (Ulmus minor) is sensitive to drought, and fast-growing trees are susceptible to Dutch elm disease
Full text linkDutch elm disease (DED) is decimating field elm (Ulmus minor) populations in Europe. The species is subjected to periodic DED outbreaks leading to a loss of vigor (canopy dieback, radial growth, mortality rate), but drought could also stress these riparian stands and interact with DED. However, we lack a quantitative characterization on the impacts of DED and drought on the vigor of elm populations. To assess how river geomorphology, growth rate and intrinsic water-use efficiency (iWUE) influence elm vulnerability to DED, we measured tree-ring, wood anatomy and δ13C in non-declining (ND) and declining (D) trees in an urban site. We also assessed the elm vigor status in 13 elm stands experiencing different geomorphological (river sinuosity index) and stand structural features along the middle Ebro basin (North Eastern Spain). Tree-ring and wood-anatomy series were correlated with climate variables (temperature, precipitation), a drought index and river flow data. Elm was more abundant at sites with lower river sinuosity and where Populus alba was abundant. On average, 64 ± 12 % (mean ± SE) of the elm basal area corresponded to dead trees. The probability of death was above 50 % for elms with diameter > 21 cm. Dry-warm conditions from the prior to the current summer and low spring river flow decreased elm growth. During the severe drought of 2012, the mean ring width was 36 % lower than the long-term average (2.74 mm). However, elm showed a rapid post-drought growth recovery. The earlywood diameter decreased in response to warm conditions in the previous winter. D trees grew more in the past and showed higher iWUE than ND trees. Our findings contribute to better knowledge of declining elms by showing their vulnerability to drought, and how fast-growing elm trees are prone to DED damage
Human Intervention and AI in Higher Education English Test Designing: Benefits, Challenges, and Recommendations
No full textThe rapid advancements in generative artificial intelligence (genAI) have produced significant research in recent years, highlighting the advantages of using genAI in language test designing. These advantages encompass time saving, the generation of test papers, and the enhancement of students’ experiences during stressful assessments. This paper seeks to underline the importance of human intervention in English test preparation by analysing various genAI outcomes informed by direct experience and observation.
Specifically, this study investigates the benefits and challenges associated with developing genAI-based English assessment tests for 160 Italian undergraduate students at an upper-intermediate level of English proficiency, using ChatGPT 3.5. I argue that human intervention, particularly through well-crafted prompts, is essential for achieving effective results. This paper advocates for a thoughtful approach to integrating AI in English test designing. The objective is to equip language teachers and practitioners with vital recommendations for test preparation. This guidance will assist them in navigating the intersection of AI and test design, fostering a nuanced understanding of the benefits and challenges posed by AI technology. It also emphasises the necessity of balancing technological reliance with the integrity of higher-order thinking skills. In sum, the paper stresses that human supervision and intervention are critical for producing reliable outcomes, as failures in genAI-based tests are not uncommon. While the primary focus of this study is on the context of Italian undergraduates, it also explores broader implications for the use of AI in language education globally, reinforcing the universal need for human intervention to maintain quality and ethical standards
Investigating crop ecophysiological response to water stress to improve precision irrigation strategies
Full text linkKiwifruit is a widely cultivated and economically important fruit crop. Italy is one of the largest producers of kiwifruit in the world and its industry plays an important role both nationally and internationally. In recent years, however, kiwifruit plantations and total production in several countries around the world, including Italy, have been threatened by a complex vine physiological decline syndrome triggered by soil water excess and unsuitable conditions. The current climate change scenario has serious implications for crop production and is certainly a new challenge for kiwifruit cultivation in many areas, urgently requiring more sustainable agricultural practices and adaptation strategies.
Kiwifruit is known to be extremely sensitive to climate and irrigation levels, which affect the viability of kiwifruit growing areas. A low physiological tolerance to drought and waterlogging makes the soil water environment important for healthy growth and optimum production of kiwifruit vines.
This thesis then focuses on evaluating the physiological responses of yellow-fleshed kiwifruit to water stress (both deficit and excess), thereby increasing the knowledge useful for implementing more precise irrigation strategies for this crop. Overall, the aims of this thesis were i) to comprehensively describe the physiological responses of yellow-fleshed kiwifruit vines to water stress, which is increasingly occurring due to climate change and improper irrigation management, ii) to implement more precise irrigation for such a sensitive crop in a very challenging environment (also due to the expected impacts of climate change), and iii) to evaluate the tolerance/susceptibility of different kiwifruit rootstocks to water stress in order to identify more tolerant genotypes to abiotic stress in kiwifruit.
First, a field experiment was conducted to evaluate the physiological behavior of yellow-fleshed kiwifruit vines under varying soil water availability in a Mediterranean environment. This study showed that kiwifruit can cope with challenging Mediterranean environmental conditions by precisely managing irrigation, distributing the right amount of irrigation water to meet the vines' water needs at the right time and place. Drought stress was imposed to study the physiological responses of the vines, through the analysis of the diurnal trends of stem water potential and stomatal conductance, identifying the onset of stress. Daily dynamics of soil water availability reduction and root uptake highlighted the importance of water availability in the top soil layers to provide the amount of water needed by the vines. Soil moisture thresholds were identified to provide the most suitable soil water environment and guide irrigation decisions. In addition, plant measurements (i.e., sap flow and trunk water potential) were used in combination with a mechanistic plant model to characterize the hydraulic behavior of kiwifruit vines under different soil water availability conditions (i.e., well-watered and drought stress). As plant variables are monitored continuously, the modelling approach provides valuable information on the hydraulic functioning of vines under field conditions and throughout the season, and shows great potential for the development of irrigation decision support tools.
In a further step, drought and waterlogging induced responses of different kiwifruit rootstocks and scion/rootstock combinations were investigated. The differential response of the investigated genotypes was evaluated through an integrated physiological and phenotyping approach. In particular, image analysis was performed at the ALSIA 'Metapontum Agrobios' research centre (PhenoLab platform), which is part of the European Plant Phenotyping Network and infrastructures. Physiological and image-based phenotyping assessment provided an effective methodology to conduct a screening for more tolerant kiwifruit genotypes to water stress. The 'Bounty' rootstock was identified as the least susceptible to water stress and 'Hayward' and 'D1' as the most susceptible.
The results obtained will hopefully open the way to further studies that will support kiwifruit production in Italy and help to face new challenges in its cultivation
Search for a heavy resonance decaying into a Z and a Higgs boson in events with an energetic jet and two electrons, two muons, or missing transverse momentum in proton-proton collisions at sqrt{s} = 13 TeV
No full textA search is presented for a heavy resonance decaying into a Z boson and a Higgs (H) boson. The analysis is based on data from proton-proton collisions at a centre-of-mass
energy of 13 TeV corresponding to an integrated luminosity of 138 fb−1, recorded with the CMS experiment in the years 2016–2018. Resonance masses between 1.4 and 5 TeV are considered, resulting in large transverse momenta of the Z and H bosons. Final states that result from Z boson decays to pairs of electrons, muons, or neutrinos are considered. The H boson is reconstructed as a single large-radius jet, recoiling against the Z boson. Machine-learning flavour-tagging techniques are employed to identify decays of a Lorentz-boosted H boson into pairs of charm or bottom quarks, or into four quarks via the intermediate H → WW∗ and ZZ∗ decays. The analysis targets H boson decays that were not generally included in previous searches using the H → b b channel. Compared with previous analyses, the sensitivity for high resonance masses is improved significantly in the channel where at most one b quark is tagged
Review of searches for vector-like quarks, vector-like leptons, and heavy neutral leptons in proton–proton collisions at √s=13 TeV at the CMS experiment
No full textThe LHC has provided an unprecedented amount of proton–proton collision data, bringing forth exciting opportunities to address fundamental open questions in particle physics. These questions can potentially be answered by performing searches for very rare processes predicted by models that attempt to extend the standard model of particle physics. The data collected by the CMS experiment in 2015–2018 at a center-of-mass energy of 13TeV can be used to test the standard model with high precision and potentially uncover evidence for new particles or interactions. An interesting possibility is the existence of new fermions with masses ranging from the MeV to the TeV scale. Such new particles appear in many possible extensions of the standard model and are well motivated theoretically. New fermions may explain the appearance of three generations of leptons and quarks, the mass hierarchy across these generations, and the nonzero neutrino masses. In this report, the results of searches targeting vector-like quarks, vector-like leptons, and heavy neutral leptons at the CMS experiment are summarized. The complementarity of current searches for each type of new fermion is discussed, and combinations of several searches for vector-like quarks are presented. The discovery potential for some of these searches at the High-Luminosity LHC is also discussed
Agronomic Performance in Durum Wheat–Vetch Intercropping: An Agroecological Strategy for Resource Use Efficiency.
No full textCrop diversification is a fundamental agroecological strategy to enhance resource use
efficiency, improve soil fertility, and increase the resilience of agricultural systems to climatic
variability. Intercropping between durum wheat (Triticum durum Desf.) and common vetch
(Vicia sativa L.) represents a viable approach to achieving these objectives in Mediterranean
organic farming. This study investigates the agronomic interactions between wheat and vetch
under simultaneous sowing and harvesting, focusing on yield performance, nitrogen (N)
dynamics, and overall system efficiency. A two-year field experiment was conducted in
southern Italy, in the Basilicata region, using an additive intercropping model, optimizing
species densities to balance complementarity and competition. Results demonstrate that
intercropping enhances nitrogen use efficiency and increases total N uptake compared to
monocultures. The land equivalent ratio consistently exceeded 1, confirming superior resource
utilization. Moreover, intercropping improved wheat grain protein content, indicating enhanced
N availability. Despite inter-annual climatic variability, intercropped systems exhibited greater
yield stability than wheat monocultures, mitigating the effects of drought stress.
Economic assessment revealed that intercropping maintains a competitive gross production
value, supporting its feasibility under low-input conditions. However, logistical challenges,
particularly post-harvest grain separation, limit broader adoption. These findings underscore
the potential of wheat–vetch intercropping to improve agronomic performance, reduce
dependence on synthetic fertilizers, and enhance system resilience, contributing to more
sustainable Mediterranean cropping systems
Measurement of multidifferential cross sections for dijet production in proton-proton collisions at at sqrt(s) = 13 TeV
No full textA measurement of the dijet production cross section is reported based on proton–proton collision data collected in 2016 at √s = 13 TeV by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of up to 36.3 fb−1 . Jets are reconstructed with the anti-kT algorithm for distance parameters of R = 0.4 and 0.8. Cross sections are measured double-differentially (2D) as a function of the largest absolute rapidity |y|max of the two jets with the highest transverse momenta pT and their invariant mass m1,2 , and triple-differentially (3D) as a function of the rapidity separation y∗, the total boost yb , and either m1,2 or the average pT of the two jets. The cross sections are unfolded to correct for detector effects and are compared with fixed-order calculations derived at next-to-next-to-leading order in perturbative quantum chromodynamics. The impact of the measurements on the parton distribution functions and the strong coupling constant at the mass of the Z boson is investigated, yielding a value of αS(mZ ) = 0.1179 ± 0.0019
Measurement of the inclusive cross sections for W and Z boson production in proton-proton collisions at sqrt{s} = 5.02 and 13 TeV
No full textMeasurements of fiducial and total inclusive cross sections for W and Z boson production are presented in proton-proton collisions at √s = 5.02 and 13 TeV . Electron and muon decay modes (l = e or μ) are studied in the data collected with the CMS detector in 2017, in dedicated runs with reduced instantaneous luminosity. The data sets correspond to integrated luminosities of 298 ± 6 pb−1 at 5.02 TeV and 206 ± 5 pb−1 at 13 TeV . Measured values of the products of the total inclusive cross sections and the branching fractions at 5.02 TeV are σ(pp → W + X)B(W → lν) = 7300 ± 10 (stat) ± 60 (syst) ± 140 (lumi) pb, and σ(pp → Z+X)B(Z → l+l−) = 669 ± 2 (stat) ± 6 (syst) ±13 (lumi) pb for the dilepton invariant mass in the range of 60–120 GeV . The corresponding results at 13 TeV are 20480 ± 10 (stat) ± 170 (syst) ± 470 (lumi) pb and 1952 ± 4 (stat) ± 18 (syst) ± 45 (lumi) pb. The measured values agree with cross section calculations at next-to-next-to-leading-order in perturbative quantum chromodynamics. Fiducial and total inclusive cross sections, ratios of cross sections of W+ and W− production as well as inclusive W and Z boson production, and ratios of these measurements at 5.02 and 13 TeV are reported
Classificazione della tipologia di stress (idrico/salino) in un contesto di plant phenotyping in vite
No full textIl riconoscimento precoce e rapido dei tipi di stress abiotici potrebbe accelerare la selezione di nuove varietà resistenti allo stress, o impostare tempestivamente pratiche di gestione adeguate. Questo studio presenta una rianalisi dei dati provenienti da esperimenti di Vitis vinifera in vaso sottoposta a stress idrico e salino al fine di identificare parametri in grado di classificare il tipo di stress.
Vengono confrontati parametri di scambio gassoso dipendenti dalla conduttanza stomatica (gs) e e non-stomatici (efficienza del fotosistema II, Fv/Fm), e fenotipici (variazione della banda di colore Dark Green nelle foglie).
Nel caso dello stress salino, i valori di Fv/Fm nelle piante stressate è significativamente (p<0.05) declinato del 25% raggiungendo circa 0.6 ±0.02 SD alla fine dello stress (9 gg). Al contrario, in caso di stress idrico, i valori di Fv/Fm dopo circa 20 gg di stress erano ancora comparabili (p>0.05) a quelli iniziali (circa 0.75±0.02 SD). Tale risultato conferma che difficilmente la vite va incontro ad una fotoinibizione permanete in caso di stress idrico.
La correlazione fra gs e tasso fotosintetico netto (Pn) mostrano i valori di Pn maggiormente ridotti in caso di stress salino rispetto a quelli dello stress da siccità a valori di gs equivalenti. I modelli non-lineari (asintotici) di tali correlazioni sono risultati significativamente distinguibili (p<0.05) confermando che i due tipi di stress sottendono processi in parte diversificati.
Attraverso una PCA, le variabili Pn, traspirazione, gs, potenziale dello stelo, Fv/Fm e Dark Green sono state scomposte e le prime due PC spiegano circa 90% della varianza complessiva. Inoltre, Dark Green e Fv/Fm dominano la PC2 definita “non-stomatica” contribuendo per l’80% alla PC2 separando i tipi di stress. Il potenziale idrico dello stelo è risultato avere un peso simile fra le due PC confermando la similitudine fra i due tipi di stress e la sua bassa capacità di servire come discriminante i tipi di stress.
In conclusione, l’insieme alla classe di colore Dark Green e Fv/Fm potrebbe supportare l'identificazione precoce e non distruttiva del tipo di stress
Observation of WZγ production and constraints on new physics scenarios in proton-proton collisions at sqrt{s} = 13 TeV
No full textA measurement of the WZγ triboson production cross section is presented. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of √s =13 TeV recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb−1. The analysis focuses on the final state with three charged leptons, l±νl+l−, where l =e or μ, accompanied by an additional photon. The observed (expected) significance of the WZγ signal is 5.4 (3.8) standard deviations. The cross section is measured in a fiducial region, where events with an l originating from a tau lepton decay are excluded, to be 5.48 ±1.11 fb, which is compatible with the prediction of 3.69 ±0.24 fb at next-to-leading order in quantum chromodynamics. Exclusion limits are set on anomalous quartic gauge couplings and on the production cross sections of massive axionlike particles