Aula Verde (tree room) as a link between art and science to raise public awareness of nature-based solutions

Nature-based solutions inherently require a multifaceted perspective that encompasses diverse fields. The aim of this project is to develop more effective nature-based solutions, climate action and environmental awareness by breaking down boundaries between disciplines and fostering a co-creative process. Concepts of ecology and urban forestry were combined with the research on political ecology, environmental humanities, land art, regenerative art, performing art, participatory art, and more-than-human art. This process resulted in the creation of Aula Verde Aniene. It is located in an urban park in Rome and consists of a stand of trees arranged in circles with a specific design to give the perception of being in an outdoor vegetated room. The project activities involved community participation through art performances and citizen science initiatives. Regulating and cultural ecosystem services of Aula Verde were assessed using i-Tree Eco software and citizens' surveys. Beyond numerical descriptions of ecosystem services, the manuscript introduces shinrin-yoku as a practice to raise awareness of nature. The distinctive approach here described contributed to convey a sense of belonging to the ecosystem to citizens. The project framework and study findings have been developed to formulate policy recommendations and disseminate a format that can be adapted to diverse locations.

Neurological research in Italy from 2020 to 2023

BACKGROUND

To assess the state of neurological scientific research in Italy in the time interval 2020-2023.

METHODS

Elsevier's modular integrated platform "SciVal" was used to analyze bibliometric research products starting from scientific production data uploaded onto Scopus. We considered the research area "Neurology" in the 01/01/2020-14/06/2023 time interval, and the following variables were extracted: number of published studies, number of citations, Field-Weighted Citation Impact, and percentage of international collaborations. The contribution of Italian scientists to the neurological research was compared to that of the other nations.

RESULTS

Research identified 90,633 scientific papers in the neurological area worldwide, with a total of 472,750 citations. The products assigned to Italian groups were 6670 (53,587 citations, Field-Weighted Citation Impact 1.68, 41% international collaborations).

CONCLUSIONS

According to the present study, Italian neurological research 2020 to 2023 ranks fifth globally and third in Europe.

Fetal aortic isthmus Doppler assessment to predict the adverse perinatal outcomes associated with fetal growth restriction: systematic review and meta-analysis

PURPOSE

Fetal growth restriction (FGR) management and delivery planning is based on a multimodal approach. This meta-analysis aimed to evaluate the prognostic accuracies of the aortic isthmus Doppler to predict adverse perinatal outcomes in singleton pregnancies with FGR.

METHODS

PubMed, EMBASE, the Cochrane Library, ClinicalTrials.gov and Google scholar were searched from inception to May 2021, for studies on the prognostic accuracy of anterograde aortic isthmus flow compared with retrograde aortic isthmus flow in singleton pregnancy with FGR. The meta-analysis was registered on PROSPERO and was assessed according to PRISMA and Newcastle-Ottawa Scale. DerSimonian and Laird's random-effect model was used for relative risks, Freeman-Tukey Double Arcsine for pooled estimates and exact method to stabilize variances and CIs. Heterogeneity was quantified using I2 statistics.

RESULTS

A total of 2933 articles were identified through the electronic search, of which 6 studies (involving 240 women) were included. The quality evaluation of studies revealed an overall acceptable score for study group selection and comparability and substantial heterogeneity. The risk of perinatal death was significantly greater in fetuses with retrograde Aortic Isthmus blood flow, with a RR of 5.17 (p value 0.00001). Similarly, the stillbirth rate was found to have a RR of 5.39 (p value 0.00001). Respiratory distress syndrome had a RR of 2.64 (p value = 0.03) in the group of fetuses with retrograde Aortic Isthmus blood flow.

CONCLUSION

Aortic Isthmus Doppler study may add information for FGR management. However, additional clinical trial are required to assess its applicability in clinical practice.

Failure Mode and Effects Analysis for Treatment Workflow of a Novel Ring Gantry Linac

PURPOSE/OBJECTIVE(S)

A new ring gantry Linac machine combined with a PET ring is available in the market. It has 3 separate centers, one for laser, one for CT imaging and a 3rd for the Linac. As a first-generation machine of its kind, the workflow heavily depends on user-input. As example, it uses two separate coordinate systems, IEC for lasers and CT localization offsets and DICOM for treatment planning. The planner must manually convert between the two systems. We hypothesize that the unique design of the machine that is heavily dependent on users' input increases the potential of failure of treatment. The present work investigates failure modes for treatment delivery using the methodology of failure modes and effects analysis (FMEA) and proposes solutions to mitigate some of the failure modes (FMs).

MATERIALS/METHODS

A group of two radiation oncologists, two radiation therapists and three medical physicists was assembled. The process map for treatment delivery on the X1 was created and FMs were identified. Members independently graded each FM on 3 parameters, likelihood of occurrence, detectability of FM and level of severity on patient treatment. A grading scale of 1-5 was used with five representing the worst outcome in each parameter. Each member also identified the origin of each FM to be human, machine or clinical process. Mitigation solutions were proposed.

RESULTS

The process map of treatment delivery on X1 consists of six major processes and 24 sub-processes. A total of 27 FMs were identified, with many 19/27 (70%) caused by human errors and 7/27 (27%) caused by machine. From all responses, we tallied a median of 11 FMs (40%) that have both S≥ 4 and O or D ≥ 4. To further focus our analysis, we looked at the highest PRN scores from each member and found 7 FMs that were common. 1 FM was in "initiation of Treatment" sub-process and 6 FMs in "Treatment delivery" sub-process. Proposed solutions to these FMs were concerned with software upgrades. Examples are, allow changes in fractionation, allow dose tracking, auto calculation of couch position for various sub processes, allow DICOM image transfer and many more. The current clinical workflow that we adopted for these FMs either puts the burden on the user to confirm/verify parameters or the use of third-party software. In addition to these high-scoring FMs, we adopted changes in clinical workflow to mitigate other FMs, most of them through third-party software.

CONCLUSION

This study confirmed that the unique design and user-dependent machine environment, human failures are high accounting for 70% of FMs in treatment delivery alone. Our current workflow of the machine depends on direct user input to calculate/confirm certain parameters or the use of third-party software, which also depends on the user for proper completion of the task. Suggested solutions also included proposed improvement to the machine's software and user interface.

Leaf-level coordination principles propagate to the ecosystem scale

Fundamental axes of variation in plant traits result from trade-offs between costs and benefits of resource-use strategies at the leaf scale. However, it is unclear whether similar trade-offs propagate to the ecosystem level. Here, we test whether trait correlation patterns predicted by three well-known leaf- and plant-level coordination theories - the leaf economics spectrum, the global spectrum of plant form and function, and the least-cost hypothesis - are also observed between community mean traits and ecosystem processes. We combined ecosystem functional properties from FLUXNET sites, vegetation properties, and community mean plant traits into three corresponding principal component analyses. We find that the leaf economics spectrum (90 sites), the global spectrum of plant form and function (89 sites), and the least-cost hypothesis (82 sites) all propagate at the ecosystem level. However, we also find evidence of additional scale-emergent properties. Evaluating the coordination of ecosystem functional properties may aid the development of more realistic global dynamic vegetation models with critical empirical data, reducing the uncertainty of climate change projections.

Can a validated website help improve university students' e-health literacy?

Background

The fight against fake news, mainly spread through Internet, is a major public health issue, even among undergraduate students. This study aims to evaluate the effectiveness of a website promoted by the Italian Federation of the Provincial Orders of the Medical Doctors as a first aid communication kit for health topics.

Study design

Pre-post study using a web-based survey, conducted in April-May 2019 on Medical students and October-November 2020 on Communication Sciences students at the University of Florence (Italy). Methods. Undergraduate students of both schools were exposed to the use of the "dottoremaeveroche" website. Primary and secondary outcomes measures: the Italian-electronic Health Literacy Scale self-assessment tool was used to examine subjects' electronic Health literacy, and source quality. All responses were rated on a 5-point Likert scale. Changing in perception of abilities were examined using the Wilcoxon test.

Results

The 362 participants felt moderately confident in electronic Health Literacy, with an initial Italian-electronic Health Literacy Scale overall mean score of 3.6±0.7 for medical and 3.2±0.8 for communication students. Medical students had a good idea of how to find helpful sources (3.9±0.8) and communication students felt confident in recognizing their quality (3.5±1.0). In contrast, their confidence in using Web information to make health decisions was low (medical: 2.9±1.1; communication: 2.8±1.1). All items improved significantly after "dottoremaeveroche" use (p<.001), with the overall mean score of Italian-electronic Health Literacy Scale increasing to 4.3±0.6 for medical and 4.1±0.8 for communication students.

Conclusions

Low electronic health literacy levels can affect public health efforts, as seen during the COVID-19 pandemic. The effectiveness of "dottoremaeveroche" among students showed the usefulness of online educational interventions that, if further implemented, could help combat the spread of infodemic.

HIPK2 in the physiology of nervous system and its implications in neurological disorders

HIPK2 is an evolutionary conserved serine/threonine kinase with multifunctional roles in stress response, embryonic development and pathological conditions, such as cancer and fibrosis. The heterogeneity of its interactors and targets makes HIPK2 activity strongly dependent on the cellular context, and allows it to modulate multiple signaling pathways, ultimately regulating cell fate and proliferation. HIPK2 is highly expressed in the central and peripheral nervous systems, and its genetic ablation causes neurological defects in mice. Moreover, HIPK2 is involved in processes, such as endoplasmic reticulum stress response and protein aggregate accumulation, and pathways, including TGF-β and BMP signaling, that are crucial in the pathogenesis of neurological disorders. Here, we review the data about the role of HIPK2 in neuronal development, survival, and homeostasis, highlighting the implications in the pathogenesis of neurological disorders, and pointing out HIPK2 potentiality as therapeutic target and diagnostic or prognostic marker.

Digital Health Literacy and Infodemic: the impact on Italian medical students between 2019-2020

Background

The COVID-19 infodemic is putting pressure on public health systems to control the pandemic. With the internet and social media playing a key role in emergency communication, digital health literacy (DHL) can be considered a determinant of health. This study aims to assess the impact of infodemic on the skills of medical students, for whom low levels of DHL may affect the ability to identify the best available medical evidence.

Methods

A cross-sectional web-based survey was conducted at the University of Florence (Italy) in Apr-May 2019 (pre-pandemic period) and in Nov-Dec 2020 (pandemic period) to investigate DHL skills. Two different cohorts of students, both in their first year of medical school, participated in the survey. The 8-item self-assessment tool (IT-eHEALS) with a 5-point Likert scale was used to examine DHL. The change in perception of ability between the two cohorts was examined using the Wilcoxon test.

Results

A total of 329 students participated in the survey in 2019 (F: 58.1%; mean age 20.6±2.1) and 341 in 2020 (F:61.9%; mean age 19.8±2.0). In 2019, participants’ DHL level was moderate with a IT-eHEALS overall mean score (MS) of 28.4±5.8. Students had a good idea of how to find helpful health information (MS 3.9±0.8) and how to use the web for this purpose (MS 3.8±0.9), but they were less confident about the usefulness of the information they received (MS 2.9±1.1). In 2020, the medical students’ DHL level deteriorated as the overall MS of IT-eHEALS decreased to 23.4±7.2 (p < 0.01). The scores of the IT-eHEALS items were significantly lower and students indicated that they found it difficult to assess the information they found (MS 2.4±1.1; p < 0.01).

Conclusions

DHL can contrast infodemic, but the latter in turn may have a negative impact on perceived DHL skills if personal knowledge base is not well structured. Training programmes for medical students as future health care providers should be reinforces to guide their practise.

Key messages

Comparison of harmonic shears, diode laser, and scissor cutting and suturing for caudal palatoplasty in dogs with brachycephalic obstructive airway syndrome

Traditionally, staphylectomy has been performed using scissors cutting and suturing. Alternative surgical techniques such as staphylectomy with monopolar electrocoagulation, CO₂ or diode laser, bipolar vessel sealing device and harmonic shears have also been described. The purpose of this prospective study was to compare the difference in surgical time, intraoperative haemorrhage and histological damage between staphylectomy performed with harmonic shears (HSS), diode laser (DLS) and traditional scissor 'cutting and suturing' technique with Metzenbaum scissors (SIS). Group HSS included 17 dogs, whereas Group DLS and Group SIS included 10 dogs each. Double masked histological evaluation was performed on the excised specimens. The harmonic shears resulted in the shortest surgical times (HSS 46 s, DLS 300 s, SIS 360 s; P < 0.001). There was a difference in the intraoperative haemorrhage among the three techniques; intraoperative haemorrhage did not occur in HSS and DLS groups. HSS was associated with more frequent damage involving the connective tissue (P = 0.001), muscle (P = 0.038), salivary gland tissue (P < 0.001), but less oedema was observed (P < 0.001). HSS was the fastest of the techniques evaluated for caudal elongated soft palate resection, resulting in less tissue oedema, and no intra-operative haemorrhage. These characteristics might result in reduced postoperative swelling and airway obstruction compared to other techniques.

Instrumental Timed Up and Go test discloses abnormalities in patients with Cervical Dystonia

Background Cervical dystonia is a movement disorder characterized by involuntary and sustained contraction of the neck muscles that determines abnormal posture. The aim of this study was to investigate whether dystonic posture in patients with cervical dystonia affects walking and causes postural changes. Methods Patients with cervical dystonia and a group of age-matched healthy controls underwent an instrumental evaluation of the Timed Up and Go Test. Findings All the spatio-temporal parameters of the sub-phases of the Timed up and go test had a significantly higher duration in cervical dystonia patients compared to the control group while no differences in flection and extension angular amplitudes were observed. Indeed, we found that Cervical Dystonia patients had abnormalities in turning, as well as in standing-up and sitting-down from a chair during the Timed up and go test than healthy controls. Interpretation Impairment in postural control in cervical dystonia patients during walking and postural changes prompts to develop rehabilitation strategies to improve postural stability and reduce the risk of fall in these patients.

e-Health Literacy among medical students

Background

The struggle against fake medical news, nowadays widely spread by web sources, is a main issue in public health especially in a pandemic period. Even among medical students, there is a lack of eHealth literacy (eHL) skills to solve medical problems. The Italian Medical Doctors Federation (FNOMCeO) promoted a Web source as a first-aid communication kit for basic notions in health hot-topics named “dottoremaeveroche” (DMVEC). This study aims to evaluate its effectiveness in improving eHL.

Methods

Between April and November 2019, medical students from the University of Firenze (Italy) joined a cross-sectional web-based survey before and after accessing the DMVEC Web source. The 8-item self-assessment tool (IT-eHEALS) was used to examine subject's eHL, in addition to questions on source's features and its quality. All responses were rated on a 5-points Likert scale. Changing of abilities' perception was assessed using Wilcoxon test.

Results

A total of 329 joined the survey, 42% male, mean age of 20.6±2.1. Participants felt moderately confident in eHL, in fact the initial eHEALS overall mean score was 3.6± 0.7. Students had a good perception on how to find helpful health resources (mean score 3.9±0.8) and how to use the Internet to answer health questions (mean score 3.8±0.9), but their ability in using this information to make health decisions was low (mean score 2.9±1.1). All items improved after the use of DMVEC, with overall mean score of IT-eHEALS increasing to 4.3±0.6 (p < 0.0001). Regarding source's quality, mean score related to transparency of sources, an aspect underestimated at first, increased from 3.5±1.2 to 4.7±0.7 (p < 0.0001).

Conclusions

Low levels of eHL can damage public health efforts, as seen during COVID19 pandemic. DMVEC effectiveness in medical students demonstrated that the scaling up to the general population of online educational interventions, with further implementation, could help in tackling infodemic and fake news spreading.

Key messages

Moderate levels of eHL among medical students could reflect lower levels in general population, highlighting this as critical issue in public health.

Educational programs addressed to Health professionals could be adapted and empowered considering general population as target.

Exploring new strategies for ozone-risk assessment: A dynamic-threshold case study

Tropospheric ozone is a dangerous atmospheric pollutant for forest ecosystems when it penetrates stomata. Thresholds for ozone-risk assessment are based on accumulated stomatal ozone fluxes such as the Phytotoxic Ozone Dose (POD). In order to identify the effect of ozone on a Holm oak forest in central Italy, four flux-based ozone impact response functions were implemented and tested in a multi-layer canopy model AIRTREE and evaluated against Gross Primary Productivity (GPP) obtained from observations of Eddy Covariance fluxes of CO₂. To evaluate if a clear phytotoxic threshold exists and if it changes during the year, six different detoxifying thresholds ranging between 0 and 5 nmol O₃ m^-2 s^-1 were tested. The use of species-specific rather than more general response functions based on plant functional types (PFT) increased model accuracy (RMSE reduced by up to 8.5%). In the case of linear response functions, a threshold of 1 nmol m^-2 s^-2 produced the best results for simulations of the whole year, although the tolerance to ozone changed seasonally, with higher tolerance (5 nmol m^-2 s^-1 or no ozone impact) for Winter and Spring and lower thresholds in Summer and Fall (0-1 nmol m^-2 s^-1). A "dynamic threshold" obtained by extracting the best daily threshold values from a range of different simulations helped reduce model overestimation of GPP by 213 g C m^-2 y^-1 and reduce RMSE up to 7.7%. Finally, a nonlinear ozone correction based on manipulative experiments produced the best results when no detoxifying threshold was applied (0 nmol O₃ m^-2 s^-1), suggesting that nonlinear functions fully account for ozone detoxification. The evidence of seasonal changes in ozone tolerance points to the need for seasonal thresholds to predict ozone damage and highlights the importance of performing more species-specific manipulative experiments to derive response functions for a broad range of plant species.

Could implant position influence the peri-implant parameters in edentulous mandibles of diabetics rehabilitated with overdentures? A split-mouth randomized study

This randomized controlled trial assessed the impact of crestal level position of implants installed in type 2 diabetes mellitus (T2DM) patients rehabilitated with overdentures. Twenty-two mandibular edentulous T2DM patients were submitted to implant placement for retention of an overdenture. By means of a split-mouth design, two implants were installed: one at supracrestal level (SL) and one at crestal level (CL). Clinical, immunoenzymatic and tomographic analyses were performed at prosthesis placement (baseline) and after 6, 12 and 24 months following implant loading. Increased peri-implant probing depths were detected in CL implants when compared with SL implants at all time-points (baseline P=0.047; 6 months P=0.014; 12 months P=0.027; 24 months P=0.036). Indeed, augmented clinical attachment levels were also detected in CL implants when compared with SL implants at all time-points (baseline P=003; 6 months P=0.045; 12 months P=0.029; 24 months P=0.026). CL implants demonstrated increased amounts of interleukin-6 (IL-6) at 6 months (P=0.043) and higher IL-17 (P=0.021), IL-21 (P=0.034) and tumour necrosis factor alpha (TNF-α) concentrations (P=0.030) at 24 months in comparison with SL implants. CL group revealed enhanced bone loss from baseline to 6 (P=0.032), 12 (P=0.043) and 24 months (P=0.028) when compared with SL. In conclusion, this study showed that implants placed supracrestally in T2DM patients rehabilitated with overdentures demonstrated lower bone loss and better clinical parameters with beneficial modulation of peri-implant immunoinflammatory biomarkers when compared with implants positioned at crestal level.

Testing Removal of Carbon Dioxide, Ozone, and Atmospheric Particles by Urban Parks in Italy

Cities are responsible for more than 80% of global greenhouse gas emissions. Sequestration of air pollutants is one of the main ecosystem services that urban forests provide to the citizens. The atmospheric concentration of several pollutants such as carbon dioxide (CO₂), tropospheric ozone (O₃), and particulate matter (PM) can be reduced by urban trees through processes of adsorption and deposition. We predict the quantity of CO₂, O₃, and PM removed by urban tree species with the multilayer canopy model AIRTREE in two representative urban parks in Italy: Park of Castel di Guido, a 3673 ha reforested area located northwest of Rome, and Park of Valentino, a 42 ha urban park in downtown Turin. We estimated a total annual removal of 1005 and 500 kg of carbon per hectare, 8.1 and 1.42 kg of ozone per hectare, and 8.4 and 8 kg of PM₁₀ per hectare. We highlighted differences in pollutant sequestration between urban areas and between species, shedding light on the importance to perform extensive in situ measurements and modeling analysis of tree characteristics to provide realistic estimates of urban parks to deliver ecosystem services.

Toxicological assessment and developmental abnormalities induced by butylparaben and ethylparaben exposure in zebrafish early-life stages

Toxicological effects of butylparaben (BuP) and ethylparaben (EtP) on zebrafish (Danio rerio) early-life stages are not well established. The present study evaluated, using zebrafish embryos and larvae, the toxicity of BuP and EtP through benchmark dose (BMD) approach. BuP was more toxic than EtP to zebrafish larvae. In fact, Lethal Concentration 50 (LC50) values at 96 h post-fertilization (hpf) for BuP and EtP were 2.34 mg/L and 20.86 mg/L, respectively. Indeed, BMD confidence interval (lower bound (BMDL) - upper bound (BMDU) was 0.91-1.92 mg/L for BuP and 10.8-17.4 mg/L for EtP. Zebrafish embryos exposed to 1 mg/L, 2.5 mg/L of BuP and 5 mg/L, 10 mg/L, 20 mg/L, 30 mg/L of EtP showed several developmental abnormalities and teratological effects compared to negative control. Exposed zebrafish developed reduced heartbeat, reduction in blood circulation, blood stasis, pericardial edema, deformed notochord and misshaped yolk sac. Embryos exposed to the highest concentrations of the chemicals (2.5 mg/L of BuP, 10 mg/L, 20 mg/L and 30 mg/L of EtP) showed the developmental abnormalities at 48 hpf while those treated with 1 mg/L of BuP and 10 mg/L of EtP reported behavioral changes at 72 hpf, including trembling of head, pectoral fins and spinal cord. This research identified the lethal and sublethal effects of BuP and EtP in zebrafish early-life stages and could be helpful to elucidate the developmental pathways of toxicity of parabens.

Current and future impacts of drought and ozone stress on Northern Hemisphere forests

Rising ozone (O₃ ) concentrations, coupled with an increase in drought frequency due to climate change, pose a threat to plant growth and productivity which could negatively affect carbon sequestration capacity of Northern Hemisphere (NH) forests. Using long-term observations of O₃ mixing ratios and soil water content (SWC), we implemented empirical drought and O₃ stress parameterizations in a coupled stomatal conductance-photosynthesis model to assess their impacts on plant gas exchange at three FLUXNET sites: Castelporziano, Blodgett and Hyytiälä. Model performance was evaluated by comparing model estimates of gross primary productivity (GPP) and latent heat fluxes (LE) against present-day observations. CMIP5 GCM model output data were then used to investigate the potential impact of the two stressors on forests by the middle (2041-2050) and end (2091-2100) of the 21st century. We found drought stress was the more significant as it reduced model overestimation of GPP and LE by ~11%-25% compared to 1%-11% from O₃ stress. However, the best model fit to observations at all the study sites was obtained with O₃ and drought stress combined, such that the two stressors counteract the impact of each other. With the inclusion of drought and O₃ stress, GPP at CPZ, BLO and HYY is projected to increase by 7%, 5% and 8%, respectively, by mid-century and by 14%, 11% and 14% by 2091-2100 as atmospheric CO₂ increases. Estimates were up to 21% and 4% higher when drought and O₃ stress were neglected respectively. Drought stress will have a substantial impact on plant gas exchange and productivity, off-setting and possibly negating CO₂ fertilization gains in future, suggesting projected increases in the frequency and severity of droughts in the NH will play a significant role in forest productivity and carbon budgets in future.

Embryotoxicity of methylparaben to zebrafish (Danio rerio) early-life stages

Methylparaben (MeP) is widely used as preservative in personal care products, food commodities and pharmaceuticals due to its antimicrobial properties. Its widespread use resulted in the contamination of aquatic environment and raised concerns about the potential adverse effects on human health, especially in the developing organisms. The aim of the present study was to evaluate the embryotoxicity of MeP in zebrafish early-life stages applying the benchmark-dose (BMD) methodology to Fish embryo acute toxicity (FET) tests-OECD guideline 236. Toxic effects were studied by daily evaluation of lethal endpoints, hatching rate and sublethal alterations. Zebrafish fertilized eggs were exposed until 96 h post fertilization (hpf) to five concentrations of MeP: 1 mg/L, 10 mg/L, 30 mg/L, 60 mg/L and 80 mg/L. The lethal concentration 50 (LC 50) was 72.67 mg/L. Indeed, BMD confidence interval (lower bound, BMDL-upper bound, BMDU) was 40.8-57.4 mg/L for lethal endpoints and 16-26.5 mg/L for toxicity index, that includes both lethal and sublethal alterations. Zebrafish embryos exposed to MeP developed sublethal alterations including pericardial edema, yolk edema, blood stasis, reduction in blood circulation, reduced heartbeat and notochord curvature. The number of embryos exposed to the highest concentrations of MeP that reported sublethal alterations increased between 24hpf and 48 hpf-72 hpf-96 hpf. Only zebrafish larvae treated with 30 mg/L of MeP showed behavioural changes. This study highlighted the detrimental effects of MeP on zebrafish early-life stages with attention to its developmental toxicity.

SOD1 p.D12Y variant is associated with amyotrophic lateral sclerosis/distal myopathy spectrum

BACKGROUND AND PURPOSE

The aim of our study was to describe patients with the p.D12Y variant (previously reported as D11Y) in SOD1 showing heterogeneous clinicopathological features.

METHODS

We performed clinical, electrophysiological, magnetic resonance imaging (MRI) and muscle pathology studies in four SOD1 p.D12Y variant-positive patients.

RESULTS

The SOD1 p.D12Y clinical manifestations ranged from a benign phenotype characterized by distal distribution of muscular weakness and long survival to classic forms of amyotrophic lateral sclerosis with poor prognosis. Two patients with the distal clinical phenotype showed MRI and muscle pathology alterations indicating a concurrent muscle involvement. In one of these patients significant myopathic changes were associated with rimmed vacuolar pathology.

CONCLUSIONS

We expand the clinical spectrum of SOD1 p.D12Y variant, including predominant lower motor neuron forms with long survival and classic forms with aggressive course. Some patients may have concomitant distal myopathy without other explanations. Given clinical, MRI and muscle pathology alterations, SOD1 should be considered in the differential diagnosis of molecularly undefined distal myopathies with rimmed vacuoles.

Water use strategy affects avoidance of ozone stress by stomatal closure in Mediterranean trees-A modelling analysis

Both ozone (O₃ ) and drought can limit carbon fixation by forest trees. To cope with drought stress, plants have isohydric or anisohydric water use strategies. Ozone enters plant tissues through stomata. Therefore, stomatal closure can be interpreted as avoidance to O₃ stress. Here, we applied an optimization model of stomata involving water, CO₂ , and O₃ flux to test whether isohydric and anisohydric strategies may affect avoidance of O₃ stress by stomatal closure in four Mediterranean tree species during drought. The data suggest that stomatal closure represents a response to avoid damage to the photosynthetic mechanisms under elevated O₃ depending on plant water use strategy. Under high-O₃ and well-watered conditions, isohydric species limited O₃ fluxes by stomatal closure, whereas anisohydric species activated a tolerance response and did not actively close stomata. Under both O₃ and drought stress, however, anisohydric species enhanced the capacity of avoidance by closing stomata to cope with the severe oxidative stress. In the late growing season, regardless of the water use strategy, the efficiency of O₃ stress avoidance decreased with leaf ageing. As a result, carbon assimilation rate was decreased by O₃ while stomata did not close enough to limit transpirational water losses.

Toward stomatal-flux based forest protection against ozone: The MOTTLES approach

European standards for the protection of forests from ozone (O₃) are based on atmospheric exposure (AOT40) that is not always representative of O₃ effects since it is not a proxy of gas uptake through stomata (stomatal flux). MOTTLES "MOnitoring ozone injury for seTTing new critical LEvelS" is a LIFE project aimed at establishing a permanent network of forest sites based on active O₃ monitoring at remote areas at high and medium risk of O₃ injury, in order to define new standards based on stomatal flux, i.e. POD_Y (Phytotoxic Ozone Dose above a threshold Y of uptake). Based on the first year of data collected at MOTTLES sites, we describe the MOTTLES monitoring station, together with protocols and metric calculation methods. AOT40 and POD_Y, computed with different methods, are then compared and correlated with forest-health indicators (radial growth, crown defoliation, visible foliar O₃ injury). For the year 2017, the average AOT40 calculated according to the European Directive was even 5 times (on average 1.7 times) the European legislative standard for the protection of forests. When the metrics were calculated according to the European protocols (EU Directive 2008/50/EC or Modelling and Mapping Manual LTRAP Convention), the values were well correlated to those obtained on the basis of the real duration of the growing season (i.e. MOTTLES method) and were thus representative of the actual exposure/flux. AOT40 showed opposite direction relative to PODY. Visible foliar O₃ injury appeared as the best forest-health indicator for O₃ under field conditions and was more frequently detected at forest edge than inside the forest. The present work may help the set-up of further long-term forest monitoring sites dedicated to O₃ assessment in forests, especially because flux-based assessments are recommended as part of monitoring air pollution impacts on ecosystems in the revised EU National Emissions Ceilings Directive.

Development of food safety risk assessment tools based on molecular typing and WGS of Campylobacter jejuni genome

The ‘learning‐by‐doing’ EU‐FORA fellowship programme in the development of risk assessment tools based on molecular typing and WGS of Campylobacter jejuni genome was structured into two main activities: the primary one focused on training on risk assessment methodology and the secondary one in starting and enhancing the cooperation between the hosting and home organisations, or other joint activities. The primary activities had three subsequent work packages (WPs): WP1 data organisation, WP2 cluster and association analyses, and WP3 development of risk assessment models. The secondary activities have branched into one workshop and the initiation of a cooperation programme between the hosting and home organisations. In the last quarter, the fellow had contributed to the characterisation of some pathogens in possible response to a changing climate, part of the CLEFSA project. The fellow attended various forms of training: online and on‐site courses, and also participated at several conferences and meetings for improving his knowledge and skills, contributing to performing the Campylobacter risk assessment and source attribution.

Ozone and particle fluxes in a Mediterranean forest predicted by the AIRTREE model

Mediterranean forests are among the most threatened ecosystems by the concurrent effects of climate change and atmospheric pollution. In this work we parameterized the AIRTREE multi-layer model to predict CO₂, water, ozone, and fine particles exchanges between leaves and the atmosphere. AIRTREE consists of four different modules: (1) a canopy environmental module determines the leaf temperature and radiative fluxes at different levels from above to the bottom of the canopy; (2) a hydrological module predicts soil water flow and water availability to the plant's photosynthetic apparatus; (3) a photosynthesis module estimates the net photosynthesis and stomatal conductance, and (4) a deposition module estimates ozone and PM deposition sinks as a function of the resistances to gas diffusion in the atmosphere, and within the canopy and leaf boundary layer. We describe the AIRTREE model framework, accuracy and sensitivity by comparing modeling results against long-term continuous Eddy Covariance measurements of ozone, water, and CO₂ fluxes in a Mediterranean Holm oak forest, and we discuss potential application of AIRTREE for ozone-risk assessment in view of availability of a large observational database from ecosystems distributed worldwide.

Psychometric properties of the Italian version of the Barthel Index in patients with Parkinson's disease: a reliability and validity study

The Barthel Index (BI) is used in Italy to measure the severity of disability and to identify patients suitable for admission to rehabilitation units. The objective of this psychometric study was to validate the Italian version of the BI in a population of patients with Parkinson's disease (PD). The study was conducted at three neurological and rehabilitation centres in Rome, Italy. The BI was administered to outpatients with PD. The reliability of the scale was assessed using Cronbach's alpha for internal consistency; the intra-class correlation coefficient (ICC) was used to measure its intra- and inter-rater reliability. Pearson's correlation coefficient was calculated to evaluate its validity, comparing it with the Parkinson's disease Questionnaire (PDQ-39), the Italian version of the Geriatric Depression Scale (GDS), the Hospital Anxiety and Depression Scale (HADS), and the Short Form 36-Health Survey Questionnaire (SF-36). The BI was administered to 94 patients with PD. The psychometric properties measured were significant: Cronbach's alpha was 0.866 and the ICC for intra- and inter-rater reliability was 0.998 and 0.993, respectively. Pearson's correlation coefficient showed good correlation with the PDQ-39, GDS, HADS and SF-36 (p < 0.01). The BI is a valid and reliable tool for measuring disability in a PD population.

Disease progression in blepharospasm: a 5-year longitudinal study

BACKGROUND AND PURPOSE

The clinical manifestation of dystonic spasms in blepharospasm (BSP) patients may be heterogeneous. Whether the varying phenomenology of eyelid spasms becomes manifest sequentially during the course of the disease or aggregates in separate clusters according to different disease courses is still unclear. For this purpose, the clinical features in BSP patients were evaluated longitudinally over a 5-year period and also the blink reflex recovery cycle was tested in a subgroup of BSP patients.

METHODS

Sixty BSP patients were videotaped at time 0 and after approximately 5 years of follow-up. Two experts in movement disorders, who were blinded to the video order, reviewed the videotapes and scored the severity of BSP using the Blepharospasm Severity Rating Scale. Changes in the R2 recovery index were also evaluated in 18 patients twice, i.e. upon enrolment and at the follow-up.

RESULTS

The severity of BSP worsened significantly over the 5-year follow-up period owing to the appearance or the increased duration and frequency of prolonged spasms. It was also found that the blink reflex recovery cycle worsened at follow-up in comparison with the baseline.

CONCLUSIONS

This study shows that the disease progression of BSP is characterized by the appearance or worsening of prolonged spasms. Prolonged spasms are accompanied by changes in the excitability of brainstem interneurons. Aging-related effects may exacerbate the pathophysiological mechanisms underlying spasms.

Intensive Alternating Combination Chemotherapy and High Dose Chest Radiotherapy in Small Cell Lung Cancer

Sixty-nine patients, 32 with limited and 37 with extensive small cell lung cancer (SCLC), were admitted to the present study. Patients with limited disease underwent alternating combination chemotherapy consisting of CAV (cyclophosphamide, adriamycin, vincristine) and PE (cisplatin and etoposide) regimens and concurrent high dose thoracic radiotherapy (6,000 cGy); prophylactic brain irradiation (3,000 cGy) was administered to complete responders. Patients with extensive disease received the same alternating chemotherapy but not radiotherapy. In the 25 evaluable patients with limited disease we obtained an objective response (OR) in 80% with a complete response (CR) in 54% and partial response (PR) in 24%, stable disease (SD) in 4% and progressive disease (PD) in 16%. Median duration of response was 9.5 months for CR and 8.5 months for PR. Median survival was 14 months for all patients with 12% long-term survivors. Toxicity was acceptable. In the 32 evaluable patients with extensive disease we observed 65.6% OR with 18.7% CR and 46.8% PR, 9.3% minimal response and 25% PD. Median duration of response was 7 months for CR and 8 months for PR. Median survival was 10 months for all patients. The treatment was well tolerated. Our study did not show a therapeutic advantage for alternating combination chemotherapy in SCLC and failed to show the use of high dose chest radiotherapy in combined modality for limited disease.

Cardiovascular diseases may play a negative role in the prognosis of amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

Only a few studies have considered the role of comorbidities in the prognosis of amyotrophic lateral sclerosis (ALS) and have provided conflicting results.

METHODS

Our multicentre, retrospective study included patients diagnosed from 1 January 2009 to 31 December 2013 in 13 referral centres for ALS located in 10 Italian regions. Neurologists at these centres collected a detailed phenotypic profile and follow-up data until death in an electronic database. Comorbidities at diagnosis were recorded by main categories and single medical diagnosis, with the aim of investigating their role in ALS prognosis.

RESULTS

A total of 2354 incident cases were collected, with a median survival time from onset to death/tracheostomy of 43 months. According to univariate analysis, together with well-known clinical prognostic factors (age at onset, diagnostic delay, site of onset, phenotype, Revised El Escorial Criteria and body mass index at diagnosis), the presence of dementia, hypertension, heart disease, chronic obstructive pulmonary disease, haematological and psychiatric diseases was associated with worse survival. In multivariate analysis, age at onset, diagnostic delay, phenotypes, body mass index at diagnosis, Revised El Escorial Criteria, dementia, hypertension, heart diseases (atrial fibrillation and heart failure) and haematological diseases (disorders of thrombosis and haemostasis) were independent prognostic factors of survival in ALS.

CONCLUSIONS

Our large, multicentre study demonstrated that, together with the known clinical factors that are known to be prognostic for ALS survival, hypertension and heart diseases (i.e. atrial fibrillation and heart failure) as well as haematological diseases are independently associated with a shorter survival. Our findings suggest some mechanisms that are possibly involved in disease progression, giving new interesting clues that may be of value for clinical practice and ALS comorbidity management.

Re-emergent tremor in Parkinson's disease: the effect of dopaminergic treatment

BACKGROUND AND PURPOSE

Patients with Parkinson's disease (PD) with resting tremor may be affected by a tremor that appears after a varying latency while a posture is maintained, a phenomenon referred to as re-emergent tremor (RET). The aim of the study was to evaluate the occurrence and clinical features of RET in patients with PD tested off and on treatment, and to compare the effect of dopaminergic treatment on RET with the effect on resting and action tremor.

METHODS

We consecutively enrolled 100 patients with PD. Patients were clinically evaluated 24 h after withdrawal of therapy (off-treatment phase) and 60 min after therapy administration (on-treatment phase). We collected the demographic and clinical data of patients with PD. The severity of the disease was assessed by means of the Hoehn and Yahr scale and Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale part III. We evaluated the latency, severity and body side affected both off and on treatment in patients with RET.

RESULTS

Re-emergent tremor was present in 24% of the patients with PD off treatment and in 19% of the patients on treatment. Dopaminergic treatment reduced the clinical severity of RET. Dopaminergic treatment increased the number of patients with unilateral RET and reduced the number of those who had bilateral RET. RET and resting tremor responded similarly to dopaminergic treatment, whereas action tremor was less responsive. Patients with RET had milder motor symptoms than patients without RET both off and on treatment.

CONCLUSIONS

Dopaminergic treatment modified RET occurrence, severity and body distribution. Dopaminergic depletion plays a role in the pathophysiology of RET.

Ozone flux in plant ecosystems: new opportunities for long-term monitoring networks to deliver ozone-risk assessments

Ozone (O₃) is a photochemically formed reactive gas responsible for a decreasing carbon assimilation in plant ecosystems. Present in the atmosphere in trace concentrations (less than 100 ppbv), this molecule is capable of inhibiting carbon assimilation in agricultural and forest ecosystems. Ozone-risk assessments are typically based on manipulative experiments. Present regulations regarding critical ozone levels are mostly based on an estimated accumulated exposure over a given threshold concentration. There is however a scientific consensus over flux estimates being more accurate, because they include plant physiology analyses and different environmental parameters that control the uptake-that is, not just the exposure-of O₃. While O₃ is a lot more difficult to measure than other non-reactive greenhouse gases, UV-based and chemiluminescence sensors enable precise and fast measurements and are therefore highly desirable for eddy covariance studies. Using micrometeorological techniques in association with latent heat flux measurements in the field allows for the partition of ozone fluxes into the stomatal and non-stomatal sinks along the soil-plant continuum. Long-term eddy covariance measurements represent a key opportunity in estimating carbon assimilation at high-temporal resolutions, in an effort to study the effect of climate change on photosynthetic mechanisms. Our aim in this work is to describe potential of O₃ flux measurement at the canopy level for ozone-risk assessment in established long-term monitoring networks.

A Rare Case of Polyostotic Fibrous Dysplasia Assessed by Bone Scintigraphy with Tc-99m Methylene Diphosphonate (MDP)

A 66-year-old man affected by polyostotic form of fibrous dysplasia in consequence of worsening of lower extremity bone pain aggravated by walking and concomitant increase of serum alkaline phosphatase and osteocalcin, was subjected first to a radionuclide study. Bone scan demonstrated a pathological uptake of the radiotracer in the craniofacial bones, right scapula, left and right posterior ribs, right hemipelvis and lower extremities confirming the diagnosis but establishing especially the extent of bone involvement, greater than expected on the basis of symptoms and X-ray findings, underlying the importance of nuclear medicine imaging in the assessment and follow-up of this rare disease.

A new method to bio-preserve sea bass fillets

In this work a bio-preservation technique was applied to sea bass fillets in order to preserve their quality. The preservation consisted in the application of two kinds of active coatings on the product surface differing in the fermentation time of alginate solution by L. reuteri plus glycerol (24 and 48 h). This technological strategy was chosen because it has been demonstrated that L. reuteri produces the reuterin as an intermediate metabolite during the anaerobic fermentation of glycerol. To assess the antimicrobial effects of sodium alginate with L. reuteri and glycerol, both in vitro and in vivo tests were carried out. The active films, in particular at 48 h fermentation, showed a good antibacterial activity, confirmed also by the major reuterin concentration. To prove the effectiveness of the treatments, microbial and sensory attributes were monitored by in vivo test on fish fillets. Results highlighted that the two active sodium alginate coatings showed a good antibacterial activity. In sea bass fillets stored at 4 °C, proliferation of main spoilage microorganisms was delayed with a consequent preservation of sensory attributes. In particular, it was found that improving the fermentation time (48 h) a better microbiological and sensory quality was achieved.

Biotechnological Approach To Preserve Fresh Pasta Quality

Fresh pasta is highly susceptible to microbial contamination because of its high water activity and nutrient content. In this study, a new biopreservation system was examined that consists of an active sodium alginate solution containing Lactobacillus reuteri and glycerol, which was added during the production process of pasta. Our aim was to extend the fresh pasta shelf life by the in situ production of reuterin, thereby avoiding the use of thermal treatments that generally compromise food sensory characteristics. Two experimental studies were carried out with the product packaged under either ordinary or modified atmospheric conditions. Microbiological and sensory quality indices were monitored to determine the effectiveness of biopreservation on product quality during storage. The use of the active solution with L. reuteri and glycerol during the production process of pasta improved both microbial and sensory quality, particularly when combined with modified atmosphere.

Development of a forecasting model for brucellosis spreading in the Italian cattle trade network aimed to prioritise the field interventions

Brucellosis caused by Brucella abortus is an important zoonosis that constitutes a serious hazard to public health. Prevention of human brucellosis depends on the control of the disease in animals. Livestock movement data represent a valuable source of information to understand the pattern of contacts between holdings, which may determine the inter-herds and intra-herd spread of the disease. The manuscript addresses the use of computational epidemic models rooted in the knowledge of cattle trade network to assess the probabilities of brucellosis spread and to design control strategies. Three different spread network-based models were proposed: the DFC (Disease Flow Centrality) model based only on temporal cattle network structure and unrelated to the epidemiological disease parameters; a deterministic SIR (Susceptible-Infectious-Recovered) model; a stochastic SEIR (Susceptible-Exposed-Infectious-Recovered) model in which epidemiological and demographic within-farm aspects were also modelled. Containment strategies based on farms centrality in the cattle network were tested and discussed. All three models started from the identification of the entire sub-network originated from an infected farm, up to the fifth order of contacts. Their performances were based on data collected in Sicily in the framework of the national eradication plan of brucellosis in 2009. Results show that the proposed methods improves the efficacy and efficiency of the tracing activities in comparison to the procedure currently adopted by the veterinary services in the brucellosis control, in Italy. An overall assessment shows that the SIR model is the most suitable for the practical needs of the veterinary services, being the one with the highest sensitivity and the shortest computation time.

Technological options to control quality of fish burgers

This research was focused on preservation strategies applied to develop fish burgers enriched with tomato flour and extra-virgin olive oil. The effects of three different gas mixtures (5:95 O2/CO2; 10:60:30 O2/CO2/N2 and 5:50:45 O2/CO2/N2) on burger quality were analyzed by monitoring microbial cell load of main spoilage microorganisms, pH and sensory properties. As expected, modified atmosphere packaging significantly affected mesophilic bacteria with a reduction of about 2 log cycles for samples under 5% O2 and 95% CO2. Afterward, the best gas mixture was used in combination with various natural antimicrobial compounds (thymol, grape fruit seed extract and biocitrus). The biocitrus showed the strike balance between microbial and sensory quality, thus suggesting to be adopted for dipping treatment of the entire fish fillet before the mincing process. Later all the strategies tested individually were combined and samples were monitored for microbiological and sensory quality. Results obtained showed that dipping treatment of fillet in biocitrus solution (20,000 ppm) under modified conditions extended the shelf life by 8 days compared to the control sample, without affecting the sensory acceptability.

Particle deposition in a peri-urban Mediterranean forest

Urban and peri-urban forests provide a multitude of Ecosystem Services to the citizens. While the capacity of removing carbon dioxide and gaseous compounds from the atmosphere has been tested, their capacity to sequestrate particles (PM) has been poorly investigated. Mediterranean forest ecosystems are often located nearby or inside large urban areas. This is the case of the city of Rome, Italy, which hosts several urban parks and is surrounded by forested areas. In particular, the Presidential Estate of Castelporziano is a 6000 ha forested area located between the Tyrrhenian coast and the city (25 km downtown of Rome). Under the hypothesis that forests can ameliorate air quality thanks to particle deposition, we measured fluxes of PM1, 2.5 and 10 with fast optical sensors and eddy covariance technique. We found that PM1 is mainly deposited during the central hours of the day, while negligible fluxes were observed for PM 2.5 and 10. A Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT v4) simulated PM emission from traffic areas in the city of Rome and showed that a significant portion of PM is removed by vegetation in the days when the plume trajectory meets the urban forest.

Characterization of transient noise in Advanced LIGO relevant to gravitational wave signal GW150914

On September 14, 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal.

GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence

We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of 3.4_{-0.9}^{+0.7}×10^{-22}. The inferred source-frame initial black hole masses are 14.2_{-3.7}^{+8.3}M_{⊙} and 7.5_{-2.3}^{+2.3}M_{⊙}, and the final black hole mass is 20.8_{-1.7}^{+6.1}M_{⊙}. We find that at least one of the component black holes has spin greater than 0.2. This source is located at a luminosity distance of 440_{-190}^{+180}  Mpc corresponding to a redshift of 0.09_{-0.04}^{+0.03}. All uncertainties define a 90% credible interval. This second gravitational-wave observation provides improved constraints on stellar populations and on deviations from general relativity.

Properties of the Binary Black Hole Merger GW150914

On September 14, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected a gravitational-wave transient (GW150914); we characterize the properties of the source and its parameters. The data around the time of the event were analyzed coherently across the LIGO network using a suite of accurate waveform models that describe gravitational waves from a compact binary system in general relativity. GW150914 was produced by a nearly equal mass binary black hole of masses 36_{-4}^{+5}M_{⊙} and 29_{-4}^{+4}M_{⊙}; for each parameter we report the median value and the range of the 90% credible interval. The dimensionless spin magnitude of the more massive black hole is bound to be <0.7 (at 90% probability). The luminosity distance to the source is 410_{-180}^{+160}  Mpc, corresponding to a redshift 0.09_{-0.04}^{+0.03} assuming standard cosmology. The source location is constrained to an annulus section of 610  deg^{2}, primarily in the southern hemisphere. The binary merges into a black hole of mass 62_{-4}^{+4}M_{⊙} and spin 0.67_{-0.07}^{+0.05}. This black hole is significantly more massive than any other inferred from electromagnetic observations in the stellar-mass regime.

GW150914: First results from the search for binary black hole coalescence with Advanced LIGO

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) simultaneously observed the binary black hole merger GW150914. We report the results of a matched-filter search using relativistic models of compact-object binaries that recovered GW150914 as the most significant event during the coincident observations between the two LIGO detectors from September 12 to October 20, 2015. GW150914 was observed with a matched filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203000 years, equivalent to a significance greater than 5.1 σ.

GW150914: First results from the search for binary black hole coalescence with Advanced LIGO

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) simultaneously observed the binary black hole merger GW150914. We report the results of a matched-filter search using relativistic models of compact-object binaries that recovered GW150914 as the most significant event during the coincident observations between the two LIGO detectors from September 12 to October 20, 2015. GW150914 was observed with a matched filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203000 years, equivalent to a significance greater than 5.1 σ.

Tests of General Relativity with GW150914

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13}  km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.