Analysis of self-thinning in Calabrian pine plantations (Pinus laricio Poiret) in Calabria (southern Italy).

Self-thinning is the natural process whereby numbers of trees per unit area decrease as average tree size increases over time. It is a process intrinsic to all forest and plant communities whose composition and structure are influenced by competition for growing space. Stands follow a relatively predictable course of density-dependent tree mortality as numbers of trees per unit area decrease with increasing average tree size. It is generally assumed that the combined effects of crown expansion and tree mortality are compensatory so that canopy closure is always maintained. In forest management, knowledge of self-thinning point and information about tree density showing a sharp increase of natural mortality is useful to determine the optimal thinning regimes at stand level. Yoda’s self-thinning line and Reineke’s stand density index are useful and widely used in plantation growth models to predict natural mortality and in process-based models; calibrating these relationships is anyway difficult. Self-thinning and size-density relationships in unthinned even-aged Calabrian pine stands in Calabria (Southern Italy) were studied. Four different diameter-density equations were fitted and compared: the Reineke's model (1933), the modification of this model proposed by Zeide (1995), the self-thinning model developed by Tang et al. (1994), the self-thinning frontier      adjusted by Vanclay & Sands (2009). Data from ninety untreated or control permanent plots in experimental areas located in artificial stands were used. Reineke's equation for fully stocked stands relates the number of trees of a stand with their square mean diameter. Zeide proposed a modication to Reineke's equation considering that the slope would not be constant, but changing with age. The selfthinning model developed by Tang et al. relates the number of trees with the square mean diameter, and assumes that in a unthinned stand, which has not reached the maximum density, the self-thinning rate increases with stand density index. The model proposed by Vanclay & Sands can be solved analytically and yields equations for the stocking and the stand basal area as an explicit function of stem diameter. It predicts that self-thinning may be regulated by the maximum basal area. Linear regressions were fitted using the REG procedure of SAS for Reineke's and Zeide’s models. For the non-linear regression the Gauss-Newton algorithm from NLIN procedure was performed. Akaike's information criterion, as a measure of the goodness of fit of the four estimated statistical models, was applied. The slope obtained by Reineke’s model (1.580) not is significantly different from the costant value of -1.605 at the 95% confidence level. When height was included in the relationships between number of trees and diameter (modification proposed by Zeide) the adjusted correlation coefficient increased and the squared mean error decreased. The stand density index calculated from Reineke's straight line previously fitted (1283 trees∙ha-1) is lower than the value obtained from the Tang’s model (1919 trees∙ha-1) but these values are not statistically different. The stand self-thinning model proposed by Tang et al., although showing an objective uncertainty due to a relatively wide confidence interval, describes better than other models the relationships between stand density and average diameter in unthinned even-aged Calabrian pine stands in Calabria (Southern Italy)

Prove di avviamento ad altofusto in un ceduo di cerro (Quercus cerris L.) del Gargano: primi risultati

Conversion trials in turkey oak (Quercus cerris L.) coppices of Gargano (Puglia, Italy): first results. Six plots have been drawn in an aged turkish oak coppice stand, 35 years after last clearcut. Compared treatments are: natural evolution of the coppice without thinning versus two thinning regimes with different intensity, both aimed to convert the stands into high forests. From 600 to 800 stems per hectare were released in the conversion plots. Plots, drawn and treated in 1996, have been measured before and immediately after thinning and remeasured five and ten years later. Conversion is successfully proceeding, the stands are assuming a high forest structure with a markedly dominated understory layer. In control plots many stems died while in the thinned stands no damage or significant natural selection occurred

Epstein-barr virus induced cellular changes in nasal mucosa

A 21-year-old man presented with nasal obstruction of the right nasal fossa of 1 year duration. Nasal endoscopy revealed in the right inferior turbinate head a rounded neoplasm about 1 cm in diameter. Cytologic study of a nasal scraping specimen disclosed numerous clusters containing columnar cells with cytomegaly, prominent multinucleation, markedly sparse shortened cilia; the cytoplasm contained an acidophil area and a small round area that stained poorly; cells with a large intracytoplasmic vacuole that was acidophil and PAS+. Serology tests using the nested polymer chain reaction (PCR) technique on serum, nasal and pharyngeal smears revealed an Epstein-Barr virus (EBV) infection that was confirmed at electron microscopy. The clinical and cytological features resolved 19 months after the initial evaluation. CONCLUSION: The authors advise carrying out clinical (endoscopy, serology, etc.) evaluation of all endonasal neoplasms and to routinely perform cytological study on nasal scraping specimens. When samples test positive for EBV, nasal and nasopharyngeal endoscopy should be performed regularly to detect possible evidence for nasopharyngeal carcinoma (NPC)

COVIDIAGNOSTIX : health technology assessment of serological tests for SARS-CoV-2 infection.

Abstract Objective In vitro diagnostic tests for SARS-COV-2, also known as serological tests, have rapidly spread. However, to date, mostly single-center technical and diagnostic performance's assessments have been carried out without an intralaboratory validation process and a health technology assessment (HTA) systematic approach. Therefore, the rapid HTA for evaluating antibody tests for SARS-COV-2 was applied. Methods The use of rapid HTA is an opportunity to test innovative technology. Unlike traditional HTA (which evaluates the benefits of new technologies after being tested in clinical trials or have been applied in practice for some time), the rapid HTA is performed during the early stages of developing new technology. A multidisciplinary team conducted the rapid HTA following the HTA Core Model® (version 3.0) developed by the European Network for Health Technology Assessment. Results The three methodological and analytical steps used in the HTA applied to the evaluation of antibody tests for SARS-COV-2 are reported: the selection of the tests to be evaluated; the research and collection of information to support the adoption and appropriateness of the technology; and the preparation of the final reports and their dissemination. Finally, the rapid HTA of serological tests for SARS-CoV-2 is summarized in a report that allows its dissemination and communication. Conclusions The rapid-HTA evaluation method, in addition to highlighting the characteristics that differentiate the tests from each other, guarantees a timely and appropriate evaluation, becoming a tool to create a direct link between science and health management

Growth model for Italian Douglas fir plantations

The fundamental elements of a growth model for Douglas fir plantations in central and southern Italy have been developed and tested. Growth and yield of Douglas fir in Italy is still estimated by yield tables. No variable density growth function has yet been published. This work concentrates on diameter and basal area growth as functions of site and stand characteristics. The model can be used both as stand (average) model or as size-class model. The main function estimates annual basal area growth of the stand through age, current basal area and site characteristics. If current diameter distribution is also known, a second function estimates size-class allotment of overall stand growth enabling distribution projection. The research is based on a set of 55 plots distributed over 3 Italian regions: Toscana, Puglia and Basilicata. In Toscana, where more than half of the plots are located, each plot has been remeasured 3 to 5 times during the last 15 years(la Marca, Scotti, 1986; Corona et al., 1990). In the other regions the plots have been established more recently (Scotti et al., 1995). The main factors influencing current stands status are: initial plantation density (ranging from 800 to over 3000 trees/ha) and thinning regime (no thinning, selective or combined, removing from 10 to over 35% of the basal area). The model is expected to become a basic tool for developing decision support systems for silvicultural planning, optimizing plantation density, thinnings and rotation for specific forest sites and timber management objectives. Results include a basic evaluation of model performance at stand and size-class level. Stand basal area is accurately estimated over a wide range of conditions. Diameter distribution projections compare quite well with correspondent observed distributions: even the worst cases do not appear to be significantly biased

Organic Electrochemical Transistor Immuno-Sensors for Spike Protein Early Detection

The global COVID-19 pandemic has had severe consequences from the social and economic perspectives, compelling the scientific community to focus on the development of effective diagnostics that can combine a fast response and accurate sensitivity/specificity performance. Presently available commercial antigen-detecting rapid diagnostic tests (Ag-RDTs) are very fast, but still face significant criticisms, mainly related to their inability to amplify the protein signal. This translates to a limited sensitive outcome and, hence, a reduced ability to hamper the spread of SARS-CoV-2 infection. To answer the urgent need for novel platforms for the early, specific and highly sensitive detection of the virus, this paper deals with the use of organic electrochemical transistors (OECTs) as very efficient ion-electron converters and amplifiers for the detection of spike proteins and their femtomolar concentration. The electrical response of the investigated OECTs was carefully analyzed, and the changes in the parameters associated with the transconductance (i.e., the slope of the transfer curves) in the gate voltage range between 0 and 0.3 V were found to be more clearly correlated with the spike protein concentration. Moreover, the functionalization of OECT-based biosensors with anti-spike and anti-nucleocapside proteins, the major proteins involved in the disease, demonstrated the specificity of these devices, whose potentialities should also be considered in light of the recent upsurge of the so-called "long COVID" syndrome

The Promotoer, a brain-computer interface-assisted intervention to promote upper limb functional motor recovery after stroke: a statistical analysis plan for a randomized controlled trial

Background: Electroencephalography (EEG)-based brain-computer interfaces (BCIs) allow to modulate the sensorimotor rhythms and are emerging technologies for promoting post-stroke motor function recovery. The Promotoer study aims to assess the short and long-term efficacy of the Promotoer system, an EEG-based BCI assisting motor imagery (MI) practice, in enhancing post-stroke functional hand motor recovery. This paper details the statistical analysis plan of the Promotoer study. Methods: The Promotoer study is a randomized, controlled, assessor-blinded, single-centre, superiority trial, with two parallel groups and a 1:1 allocation ratio. Subacute stroke patients are randomized to EEG-based BCI-assisted MI training or to MI training alone (i.e. no BCI). An internal pilot study for sample size re-assessment is planned. The primary outcome is the effectiveness of the Upper Extremity Fugl-Meyer Assessment (UE-FMA) score. Secondary outcomes include clinical, functional, and user experience scores assessed at the end of intervention and at follow-up. Neurophysiological assessments are also planned. Effectiveness formulas have been specified, and intention-to-treat and per-protocol populations have been defined. Statistical methods for comparisons of groups and for development of a predictive score of significant improvement are described. Explorative subgroup analyses and methodology to handle missing data are considered. Discussion: The Promotoer study will provide robust evidence for the short/long-term efficacy of the Promotoer system in subacute stroke patients undergoing a rehabilitation program. Moreover, the development of a predictive score of response will allow transferring of the Promotoer system to optimal clinical practice. By carefully describing the statistical principles and procedures, the statistical analysis plan provides transparency in the analysis of data. Trial registration: ClinicalTrials.gov NCT04353297 . Registered on April 15, 2020

Goal Delegation in Multiagent System

The organization of an event, like a conference, presents some aspects of distributed problem solving that we think can be tackled in an efficient way through goal delegation. Our application exploits the capabilities of both interface agents and collaborative agents to ease the work of negotiating a list of services, with different priorities and constraints. It shows that agents can approach even complex tasks through goal delegation and offer dynamic and flexible solutions for supply chains, especially to deal with unexpected events and chain reorganization

Spatial Variability of Soil Physical and Hydraulic Properties in a Durum Wheat Field: An Assessment by the BEST-Procedure

Spatial variability of soil properties at the field scale can determine the extent of agricultural yields and specific research in this area is needed. The general objective of this study was to investigate the relationships between soil physical and hydraulic properties and wheat yield at the field scale and test the BEST-procedure for the spatialization of soil hydraulic properties. A simplified version of the BEST-procedure, to estimate some capacitive indicators from the soil water retention curve (air capacity, ACe, relative field capacity, RFCe, plant available water capacity, PAWCe), was applied and coupled to estimates of structure stability index (SSI), determinations of soil texture and measurements of bulk density (BD), soil organic carbon (TOC) and saturated hydraulic conductivity (Ks). Variables under study were spatialized to investigate correlations with observed medium-high levels of wheat yields. Soil physical quality assessment and correlations analysis highlighted some inconsistencies (i.e., a negative correlation between PAWCe and crop yield), and only five variables (i.e., clay + silt fraction, BD, TOC, SSI and PAWCe) were spatially structured. Therefore, for the soil–crop system studied, application of the simplified BEST-procedure did not return completely reliable results. Results highlighted that (i) BD was the only variable selected by stepwise analysis as a function of crop yield, (ii) BD showed a spatial distribution in agreement with that detected for crop yield, and (iii) the cross-correlation analysis showed a significant positive relationship between BD and wheat yield up to a distance of approximately 25 m. Such results have implications for Mediterranean agro-environments management. In any case, the reliability of simplified measurement methods for estimating soil hydraulic properties needs to be further verified by adopting denser measurements grids in order to better capture the soil spatial variability. In addition, the temporal stability of observed spatial relationships, i.e., between BD or soil texture and crop yields, needs to be investigated along a larger time interval in order to properly use this information for improving agronomic management