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1.
Biometrics ; 80(2)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38536746

ABSTRACT

The paper extends the empirical likelihood (EL) approach of Liu et al. to a new and very flexible family of latent class models for capture-recapture data also allowing for serial dependence on previous capture history, conditionally on latent type and covariates. The EL approach allows to estimate the overall population size directly rather than by adding estimates conditional to covariate configurations. A Fisher-scoring algorithm for maximum likelihood estimation is proposed and a more efficient alternative to the traditional EL approach for estimating the non-parametric component is introduced; this allows us to show that the mapping between the non-parametric distribution of the covariates and the probabilities of being never captured is one-to-one and strictly increasing. Asymptotic results are outlined, and a procedure for constructing profile likelihood confidence intervals for the population size is presented. Two examples based on real data are used to illustrate the proposed approach and a simulation study indicates that, when estimating the overall undercount, the method proposed here is substantially more efficient than the one based on conditional maximum likelihood estimation, especially when the sample size is not sufficiently large.


Subject(s)
Models, Statistical , Likelihood Functions , Computer Simulation , Population Density , Sample Size
2.
Article in English | MEDLINE | ID: mdl-35682044

ABSTRACT

The Indian Western Himalayas (IWHs) are a world famous tourist spot, and every year millions of tourists visit this area in fossil fuel-driven vehicles. Emissions from these vehicles persistently deteriorate the pristine environment of the IWHs. Therefore, in the current study, efforts were made to assess the compromised environmental conditions of Manali, Himachal Pradesh, India that resulted from the inflow of tourists and the activities undertaken by them. This study revealed that Manali could sustainably accommodate only 0.305 M tourists/month, and this threshold was reported to be crossed in the months of April, May and June. Furthermore, to augment these findings, water and ambient air samples were collected and analyzed for the presence of elemental carbon (EC) from one of the medium tourism potential regions of Manali, i.e., the Hamta glacier. The tributary receiving water from the Hamta glacier and the ambient air of the area was observed to be contaminated with 42 ± 12 ppb and 880 ± 43 µg m-3 of EC, respectively. It was observed that the inhalation and ingestion of EC-contaminated air and water could jeopardize human health due to a high lifetime cancer risk. However, without the intervention of eco-tourism in the study area, higher environmental health effects were also speculated. The observations made in this study are expected to trigger the interests of the researchers, international scientific community and regional authorities working towards the unsustainable development of the IWHs and deteriorating environmental conditions.


Subject(s)
Air Pollutants , Neoplasms , Air Pollutants/analysis , Carbon/analysis , Environmental Monitoring/methods , Humans , India/epidemiology , Neoplasms/epidemiology , Neoplasms/etiology , Particulate Matter/analysis , Vehicle Emissions/analysis , Water
3.
Article in English | MEDLINE | ID: mdl-34281093

ABSTRACT

BACKGROUND: The present work starts from a literature review of the evolution of Integrated Management Systems (IMSs), considering different points of view and standards: quality, environmental, occupational health and safety, sustainability and social issues. Even if the benefits are possible, there is not a common approach and a clear link between the integration of management systems and business performance, in particular considering safety performance. METHODS: The present study analyzes the application of Risk Assessment in order to realize the integration of management systems. The main objective is to provide a tool for an integrated evaluation of all company performances, starting from the definition of some Key Performance Indicators-KPIs-proposed for a particular case study, even if their choice is not the core of the paper. The assessment team members on the basis of their knowledge, experience and useful literature, could choose the right KPIs for the specific application, able to take a picture of the current state and to suggest a possible recommended action of improving. The proposed Risk Assessment approach is an integration of modern management techniques: Integrated Management System and Improving Cycle DMAIC. RESULTS: The new method, called the Global Performance Index for Integrated Management System-GPI-IMS, has been applied to a real case study in the logistic field in order to evaluate its goodness and possible generalization. CONCLUSIONS: The proposed method allows to define the requirements that any company must have to perform the best. The role of the assessment team is very important to evaluate the global performance of the company and to suggest the corrective actions to be adopted.


Subject(s)
Occupational Health , Humans , Risk Assessment
4.
Article in English | MEDLINE | ID: mdl-33418973

ABSTRACT

Geosynthetics are extensively utilized to improve the stability of geotechnical structures and slopes in urban areas. Among all existing geosynthetics, geotextiles are widely used to reinforce unstable slopes due to their capabilities in facilitating reinforcement and drainage. To reduce settlement and increase the bearing capacity and slope stability, the classical use of geotextiles in embankments has been suggested. However, several catastrophic events have been reported, including failures in slopes in the absence of geotextiles. Many researchers have studied the stability of geotextile-reinforced slopes (GRSs) by employing different methods (analytical models, numerical simulation, etc.). The presence of source-to-source uncertainty in the gathered data increases the complexity of evaluating the failure risk in GRSs since the uncertainty varies among them. Consequently, developing a sound methodology is necessary to alleviate the risk complexity. Our study sought to develop an advanced risk-based maintenance (RBM) methodology for prioritizing maintenance operations by addressing fluctuations that accompany event data. For this purpose, a hierarchical Bayesian approach (HBA) was applied to estimate the failure probabilities of GRSs. Using Markov chain Monte Carlo simulations of likelihood function and prior distribution, the HBA can incorporate the aforementioned uncertainties. The proposed method can be exploited by urban designers, asset managers, and policymakers to predict the mean time to failures, thus directly avoiding unnecessary maintenance and safety consequences. To demonstrate the application of the proposed methodology, the performance of nine reinforced slopes was considered. The results indicate that the average failure probability of the system in an hour is 2.8×10-5 during its lifespan, which shows that the proposed evaluation method is more realistic than the traditional methods.


Subject(s)
Bayes Theorem , Markov Chains , Monte Carlo Method , Reproducibility of Results , Uncertainty
5.
Sci Total Environ ; 615: 1506-1517, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-29055592

ABSTRACT

Concrete industry is responsible of the most significant contribution to the global warming due to the large amount of substances with environmental impacts produced during its entire life cycle (production process, construction, maintenance, dismantlement, and scrapping). The most important issue characterizing the concrete industry is related to the constant growth of consumption of natural aggregates. The purpose of the present research is to apply the standard protocol of life cycle assessment to 3 different concrete mixtures composed by wastes from construction and demolition (C&D), marble sludge and cement kiln dust (CDK) in order to compare the environmental and energy impacts. The main purpose is to analyze the potentials (capabilities/benefits) of recycled aggregate concrete. The proposed model analyses 37 recovery possible scenarios. The results were analyzed with the software SimaPro© and with the life cycle impact assessment method Eco Indicator 99. The results show how it is possible to decide for the optimal solution in order to reduce emissions and impacts due to the concrete production.

6.
Neurol Sci ; 38(2): 279-286, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27826793

ABSTRACT

The primary aim of the study was to adopt QOLIBRI (quality of life after brain injury) questionnaire in a proxy version (Q-Pro), i.e., to use caregivers for comparison and to evaluate whether TBI patients' judgment corresponds to that of their caregivers since the possible self-awareness deficit of the persons with TBI. A preliminary sample of 19 outpatients with TBI and their proxies was first evaluated with the Patient Competency Rating Scale to assess patients' self-awareness; then they were evaluated with the QOLIBRI Patient version (Q-Pt) and a patient-centered version of the Q-Pro. Subsequently, 55 patients and their caregivers were evaluated using the patient-centered and the caregiver-centered Q-Pro versions. Q-Pt for assessing Quality of Life (QoL) after TBI, as patients' subjective perspective and Q-Pro to assess the QoL of patients as perceived by the caregivers. The majority of patients (62.2%) showed better self-perception of QoL than their proxies; however, patients with low self-awareness were less satisfied than patients with adequate self-awareness. Low self-awareness does not impair the ability of patients with TBI to report on satisfaction with QoL as self-perceived.


Subject(s)
Awareness , Brain Injuries, Traumatic/psychology , Caregivers/psychology , Quality of Life/psychology , Self Concept , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult
7.
Brain Res Bull ; 87(4-5): 373-82, 2012 Mar 10.
Article in English | MEDLINE | ID: mdl-22289841

ABSTRACT

In previous studies, we investigated a group of subjects who had suffered from a severe non missile traumatic brain injury (nmTBI) without macroscopic focal lesions and we found brain atrophy involving the hippocampus, fornix, corpus callosum, optic chiasm, and optic radiations. Memory test scores correlated mainly with fornix volumes [37,38]. In the present study, we re-examined 11 of these nmTBI subjects approximately 8 yr later. High-spatial resolution T1 weighted magnetic resonance images of the brain (1mm(3)) and standardised memory tests were performed once more in order to compare brain morphology and memory performance originally assessed 3-13 months after head injury (first study) and after 8-10 yr (present study). An overall improvement of memory test performance was demonstrated in the latest assessment, indicating that cognitive recovery in severe nmTBI subjects had not been completed within 3-13 months post-injury. It is notable that the volumes of the fornix and the hippocampus were reduced significantly from normal controls, but these volumes do not differ appreciatively between nmTBI subjects at first (after ∼1 yr) and at second (after ∼8 yr) scans. On the contrary, a clear reduction in the volume of the corpus callosus can be observed after ∼1 yr and a further significant reduction is evident after ∼8 yr, indicating that the neural degeneration in severe nmTBI continues long after the head trauma and relates to specific structures and not to the overall brain.


Subject(s)
Brain Injuries/complications , Brain Injuries/pathology , Brain/pathology , Memory Disorders/etiology , Memory Disorders/pathology , Adolescent , Adult , Aged , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Young Adult
8.
Funct Neurol ; 26(1): 15-24, 2011.
Article in English | MEDLINE | ID: mdl-21693084

ABSTRACT

The aim of this study was to review the usefulness of clinical and instrumental evaluation in individuals with disorders of consciousness (DOC). Thirteen subjects with severe acquired brain injury (ABI) and a diagnosis of DOC were evaluated using the Coma Recovery Scale in its revised version (CRS-R) and a new global disability index, the Post-Coma Scale (PCS). These instruments were administered both by a neutral examiner (professional) and by a professional in the presence of a caregiver. All patients were also scored using the International Classification of Functioning, Disability and Health (ICF). A statistically significant correlation between CRS-R and PCS was demonstrated. However, there also emerged significant differences in responsiveness between professional versus caregiver+professional assessment using the two scales. The emotional stimulation provided by significant others (caregivers) during administration of DOC evaluation scales may improve the assessment of responsiveness.


Subject(s)
Akinetic Mutism/physiopathology , Consciousness Disorders/diagnosis , Consciousness Disorders/physiopathology , Neuropsychological Tests/standards , Parkinsonian Disorders/physiopathology , Recovery of Function , Adult , Brain Injuries/complications , Brain Injuries/physiopathology , Coma/diagnosis , Coma/physiopathology , Consciousness/classification , Consciousness Disorders/etiology , Female , Humans , Male , Middle Aged , Persistent Vegetative State/diagnosis , Persistent Vegetative State/physiopathology , Reproducibility of Results , Trauma Severity Indices
9.
BMC Infect Dis ; 9: 13, 2009 Feb 05.
Article in English | MEDLINE | ID: mdl-19196453

ABSTRACT

BACKGROUND: Monitoring the incidence of bacterial meningitis is important to plan and evaluate preventive policies. The study's aim was to estimate the incidence of bacterial meningitis by aetiological agent in the period 2001-2005, in Lazio Italy (5.3 mln inhabitants). METHODS: Data collected from four sources--hospital surveillance of bacterial meningitis, laboratory information system, the mandatory infectious diseases notifications, and hospital information system--were combined into a single archive. RESULTS: 944 cases were reported, 89% were classified as community acquired. S. pneumoniae was the most frequent aetiological agent in Lazio, followed by N. meningitis. Incidence of H. influenzae decreased during the period. 17% of the cases had an unknown aetiology and 13% unspecified bacteria. The overall incidence was 3.7/100,000. Children under 1 year were most affected (50.3/100,000), followed by 1-4 year olds (12.5/100,000). The percentage of meningitis due to aetiological agents included in the vaccine targets, not considering age, is 31%. Streptococcus spp. was the primary cause of meningitis in the first three months of life. The capture-recapture model estimated underreporting at 17.2% of the overall incidence. CONCLUSION: Vaccine policies should be planned and monitored based on these results. The integrated surveillance system allowed us to observe a drop in H. influenzae b meningitis incidence consequent to the implementation of a mass vaccination of newborns.


Subject(s)
Meningitis, Bacterial/epidemiology , Population Surveillance , AIDS-Related Opportunistic Infections/epidemiology , AIDS-Related Opportunistic Infections/microbiology , Adolescent , Adult , Child , Child, Preschool , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Cross Infection/epidemiology , Cross Infection/microbiology , Disease Notification , Humans , Incidence , Infant , Italy/epidemiology , Meningitis, Bacterial/etiology , Middle Aged , Young Adult
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