Airborne trace contaminants of possible interest in CELSS

One design goal of Closed Ecological Life Support Systems (CELSS) for long duration space missions is to maintain an atmosphere which is healthy for all the desirable biological species and not deleterious to any of the mechanical components in that atmosphere. CELESS design must take into account the interactions of at least six major components; (1) humans and animals, (2) higher plants, (3) microalgae, (4) bacteria and fungi, (5) the waste processing system, and (6) other mechanical systems. Each of these major components can be both a source and a target of airborne trace contaminants in a CELSS. A range of possible airborne trace contaminants is discussed within a chemical classification scheme. These contaminants are analyzed with respect to their probable sources among the six major components and their potential effects on those components. Data on airborne chemical contaminants detected in shuttle missions is presented along with this analysis. The observed concentrations of several classes of compounds, including hydrocarbons, halocarbons, halosilanes, amines and nitrogen oxides, are considered with respect to the problems which they present to CELSS

Pyrene, a Test Case for Deep-Ultraviolet Molecular Photophysics

We determined the complete relaxation dynamics of pyrene in ethanol from the second bright state, employing experimental and theoretical broadband heterodyne detected transient grating and two-dimensional photon echo (2DPE) spectroscopy, using pulses with duration of 6 fs and covering a spectral range spanning from 250 to 300 nm. Multiple lifetimes are assigned to conical intersections through a cascade of electronic states, eventually leading to a rapid population of the lowest long-living excited state and subsequent slow vibrational cooling. The lineshapes in the 2DPE spectra indicate that the efficiency of the population transfer depends on the kinetic energy deposited into modes required to reach a sloped conical intersection, which mediates the decay to the lowest electronic state. The presented experimental–theoretical protocol paves the way for studies on deep-ultraviolet-absorbing biochromophores ubiquitous in genomic and proteic systems

Photochemical reaction paths of cis-dienes studied with RASSCF: the changing balance between ionic and covalent excited states

International audienc

Modelizations and Simulations of Nano Devices in nanok calculus

International audienceWe develop a process calculus - the nanok calculus - for modeling, analyzing and predicting the properties of molecular devices. The nanok calculus is equipped with a simple stochastic model, that we use to model and simulate the behavior of a molecular shuttle, a basic nano device currentfly used for building more complex systems

Importance of electronic self-consistency in the TDDFT based treatment of nonadiabatic molecular dynamics

A mixed quantum-classical approach to simulate the coupled dynamics of electrons and nuclei in nanoscale molecular systems is presented. The method relies on a second order expansion of the Lagrangian in time-dependent density functional theory (TDDFT) around a suitable reference density. We show that the inclusion of the second order term renders the method a self-consistent scheme and improves the calculated optical spectra of molecules by a proper treatment of the coupled response. In the application to ion-fullerene collisions, the inclusion of self-consistency is found to be crucial for a correct description of the charge transfer between projectile and target. For a model of the photoreceptor in retinal proteins, nonadiabatic molecular dynamics simulations are performed and reveal problems of TDDFT in the prediction of intra-molecular charge transfer excitations.Comment: 9 pages, 8 figures. Minor changes in content wrt older versio

Education and training among Italian postgraduate medical schools in public health: a comparative analysis

Analisi comparativa dei percorsi formativi offerti dalle Scuole di specializzazione di Igiene e Medicina Preventiva in Italia Background: Il percorso formativo dello specialista in Igiene e Medicina Preventiva dovrebbe garantire adeguate conoscenze tecnico-scientifiche e professionali nei campi della medicina preventiva, della promozione della salute e della programmazione dei servizi sanitari secondo quanto indicato anche dal DM 285/2005. La Consulta degli Specializzandi, da sempre coinvolta in attività di monitoraggio della formazione a livello nazionale, si prefigge l’obiettivo di valutare l’omogeneità delle proposte formative tra le diverse sedi italiane, non solo per segnalare le criticità, ma anche per evidenziarne le opportunità. Metodi: Lo studio, di tipo cross-sectional, è stato condotto mediante la somministrazione di un questionario semi-strutturato inviato per la compilazione ai rappresentanti delle 32 le Scuole di Igiene e Medicina Preventiva italiane. Lo strumento di valutazione è costituito da quattro sezioni: informazioni generali, attività formativa universitaria, attività formativa extra-universitaria, attività formativa intersettoriale. L’indagine è stata svolta nel periodo tra marzo e maggio 2013 ed è stata prodotta un’analisi descrittiva dei dati ottenuti. Risultati: Il questionario è stato compilato da 28 Scuole su 32 (tasso di risposta 88%), distribuite su tutto il territorio nazionale. Il numero di medici in formazione varia tra 7 e 31 e il rapporto tra docenti del settore scientifico-disciplinare di interesse e i discenti è compreso tra 0,2 e 2. Per quanto riguarda la didattica, solo in 4 Scuole si effettuano tutti i corsi previsti dal DM. La maggior parte delle sedi svolge almeno il 75% dei corsi previsti, ma esistono sedi in cui il numero di corsi è inferiore al 50%. La maggior parte delle Scuole svolge più del 60% delle attività professionalizzanti essenziali secondo il decreto, ma 2 Scuole non arrivano al 50%. Tutte le Scuole prevedono un tirocinio di 6-12 mesi in ASL, affiancando principalmente attività del Dipartimento di Prevenzione. Ovunque è previsto un periodo in Direzione Medica Ospedaliera, mentre le Strutture Riabilitative rientrano raramente nella rete formativa. Nella maggioranza delle Scuole è possibile frequentare aziende con rischio biologico oppure seguire simili attività nei Servizi dedicati della ASL. Molte Scuole, infine, consentono di frequentare diverse strutture territoriali (Agenzia di Controllo delle Acque), regionali (Assessorati) o nazionali (Ministero, Istituto Superiore di Sanità); in alcuni casi si tratta di Università gemellate e Istituti di Ricerca. Conclusioni: Nonostante il DM 285/2005 indichi quali siano le fondamenta della sanità pubblica, la flessibilità nella scelta formativa è vista come requisito essenziale per ottimizzare le risorse e contestualizzare l’adeguata formazione del medico in formazione specialistica in Igiene e Medicina Preventiva. La maggior parte delle Scuole di Specializzazione italiane dovrebbe però prevedere lo svolgimento della quasi totalità delle attività formative previste, al fine di non creare disuguaglianze formative tra gli specializzandi. Infine, considerato che la sanità pubblica è una disciplina in continuo divenire, il DM del 2005 andrebbe rivisitato tenendo in considerazione la flessibilità della formazione ed i continui cambiamenti dei bisogni di salute essenziali della popolazione. Inoltre, nel processo di rivisitazione dei bisogni formativi dei medici in formazione specialistica, dovrebbero essere coinvolti anche i discenti al fine di rafforzare il potere e l’efficacia dell’insegnamento.Background The postgraduate medical Schools in Public Health (locally known as School of Hygiene and Preventive Medicine) should ensure adequate scientific and technical knowledge and professional skills in preventive medicine, health promotion and healthcare planning as provided by Ministerial Decree 285/2005. The Italian Committee of Medical Residents in Hygiene, Preventive Medicine and Public Health of the Italian Society of Hygiene, Public Health and Preventive Medicine - S.It.I. (Consulta Nazionale dei medici in formazione specialistica S.It.I.) has always been engaged in monitoring activities on public health teaching, guaranteeing the homogeneity of educational proposals among all national Schools in Public Health. The purpose of this study is to provide a 'snapshot' of public health education and training in Italy and to identify the improvement actions needed for implementing an innovative and homogeneous public health training. Methods: A cross-sectional study was carried out over a period of three months (March to May 2013). A self-administered questionnaire was e-mailed to local Committee’s delegates of all 32 postgraduate medical Schools in Public Health in Italy. The questionnaire was structured in four sections: general information, University education and training, extra-University training, interdisciplinary activities. The majority of local Committee’s delegates have agreed to be enrolled in the survey. Results: A total of 28 questionnaires were returned (88% response rate). The number of residents in each Italian School in Public Health ranged from 7 to 31. The distribution of professors in relation to residents is not similar for each University Schools. The ratio professors/residents spanning from 0.2 to 2. About teaching, only 4 University Schools offered all courses requested by Ministerial Decree 285/2005. Most of them offered at least 75% of the requested courses, but there were Schools in which the courses were less than 50%. The vast majority of schools held more than 60% of the qualifying activities considered essential according to the Decree, while 2 Schools were below 50%. All Schools required an internship of 6-12 months in local health authority offices (ASL), mainly concerning the Department of Prevention activities. In all Schools a period of stay in a Hospital Medical Direction was scheduled, while professional activities at Residential care homes were very rarely included in training programmes. Many Schools allowed residents to attend companies with biological hazard or to follow similar activities in dedicated services of ASL. Finally, in the majority of Schools, a training period in various local (Service for Water Control), regional (Departments) or national (Ministry, National Institute of Health) health facilities was contemplated and, in some cases, also in other Universities or Research Institutes. Conclusions: Although the Ministerial Decree indicates the essential milestones of the public health education, flexibility is seen as an important element in order to optimize resources and contextualize the adequate education of residents. In any case, at least regarding public health courses, the majority of University education and extra-University training activities should be carried out by all Schools. In order to obtain shared knowledge and skills, the Ministerial Decree should be revised taking into account flexibility and changing as intrinsic characteristics of public health profession and learners should be involved in the reform to strengthening the role of public health teachin

Ten-Year Longitudinal Study of Thyroid Function in Children with Down's Syndrome

Background/Aims: The natural history of thyroid function in children with Down's syndrome is relatively unknown. We hypothesized that in these patients the occurrence of thyroid dysfunction rises during development. Methods: Thyroid function was assessed yearly in 145 children with Down's syndrome, all followed from birth up to 10 years of age. Heteroskedastic binary and ordinary logistic regression for repeated measures was used to evaluate the relationship of thyroid function with continuous time. Results: Congenital hypothyroidism was detected in 7% of cases. The probability of acquired thyroid dysfunction increased from 30% at birth to 49% at 10 years (p < 0.001). The subclinical hypothyroidism was nearly stable during the follow-up. The probability of hypothyroidism increased from 7 to 24% at 10 years (p < 0.001). Positive anti-thyroglobulin antibodies were associated with higher odds of more severe hypothyroidism (odds ratio 3.6). Positive anti-thyroid peroxidase antibodies were a better predictor of more severe hypothyroidism (odds ratio 6.1). Diffuse hypoechogenicity on thyroid ultrasound was found in 34 out of 145 children. Conclusion: The probability of thyroid dysfunction increasing during development is higher than previously reported. Such children should be carefully monitored annually to early identify thyroid dysfunction