Bow-Tie Cavity for Terahertz Radiation

We report on the development, testing, and performance analysis of a bow-tie resonant cavity for terahertz (THz) radiation, injected with a continuous-wave 2.55 THz quantum cascade laser. The bow-tie cavity employs a wire-grid polarizer as input/output coupler and a pair of copper spherical mirrors coated with an unprotected 500 nm thick gold layer. The improvements with respect to previous setups have led to a measured finesse value F=123, and a quality factor Q = 5.1x10^5. The resonator performances and the relevant parameters are theoretically predicted and discussed, and a comparison among simulated and experimental spectra is given

Retrieval of phase relation and emission profile of quantum cascade laser frequency combs

The major development recently undergone by quantum cascade lasers has effectively extended frequency comb emission to longer-wavelength spectral regions, i.e. the mid and far infrared. Unlike classical pulsed frequency combs, their mode-locking mechanism relies on four-wave mixing nonlinear processes, with a temporal intensity profile different from conventional short-pulses trains. Measuring the absolute phase pattern of the modes in these combs enables a thorough characterization of the onset of mode-locking in absence of short-pulses emission, as well as of the coherence properties. Here, by combining dual-comb multi-heterodyne detection with Fourier-transform analysis, we show how to simultaneously acquire and monitor over a wide range of timescales the phase pattern of a generic frequency comb. The technique is applied to characterize a mid-infrared and a terahertz quantum cascade laser frequency comb, conclusively proving the high degree of coherence and the remarkable long-term stability of these sources. Moreover, the technique allows also the reconstruction of electric field, intensity profile and instantaneous frequency of the emission.Comment: 20 pages. Submitted to Nature Photonic

Epidemiologia della pertosse in Puglia, 1971-2003.

none6noneR. Prato; M. Guido; M. Quattrocchi; A. Campa; M.C. Rollo; G. GabuttiR., Prato; M., Guido; M., Quattrocchi; A., Campa; M. C., Rollo; Gabutti, Giovann

Microbial and nutritional aspects on the production of live feeds in fish farming industry

Aquaculture is an enterprise in constant development, in particular relating to its effect on the environment and also the quality of its products. It represents a valid alternative to traditional fishing, facing the increasing demand for fish products. To guarantee to the consumer a product of high nutritional, organoleptic and hygienic quality, it is fundamental to monitor every phase of the fish farming industry, isolating the potential risk points. For this reason there has been a rapid evolution of productive technique, particularly in the technology, artificial reproduction and feed sectors. The aim of this research has been the monitoring of the evolution of certain microbial and nutritional quality indexes (total microbial counts and lipid analysis on suspensions of Rotifers and Artemia, used as live feed) in the larval phase of the productive cycle of the farm raised fish, in an intensive system. The study has shown an increment in the total microbial counts in the fish farming industry within the production of Rotifers and Artemia, more evident in the suspensions of Rotifers. In addition the study has demonstrated that the maintenance phase, in the enrichment protocol, can reduce the EPA and DHA content. The results confirm the importance of microbial and nutritional control of the live feeds before they get supplied to fish larvae

Microbial and nutritional aspects on the production of live feeds in a fish farming industry.

Aquaculture is an enterprise in constant development, in particular relating to its effect on the environment and also the quality of its products. It represents a valid alternative to traditional fishing, facing the increasing demand for fish products. To guarantee to the consumer a product of high nutritional, organoleptic and hygienic quality, it is fundamental to monitor every phase of the fish farming industry, isolating the potential risk points. For this reason there has been a rapid evolution of productive technique, particularly in the technology, artificial reproduction and feed sectors. The aim of this research has been the monitoring of the evolution of certain microbial and nutritional quality indexes (total microbial counts and lipid analysis on suspensions of Rotifers and Artemia, used as live feed) in the larval phase of the productive cycle of the farm raised fish, in an intensive system. The study has shown an increment in the total microbial counts in the fish farming industry within the production of Rotifers and Artemia, more evident in the suspensions of Rotifers. In addition the study has demonstrated that the maintenance phase, in the enrichment protocol, can reduce the EPA and DHA content. The results confirm the importance of microbial and nutritional control of the live feeds before they get supplied to fish larvae

Aggressive Behaviors and Verbal Communication Skills in Autism Spectrum Disorders

Aggressive behavior is a common problem among children with autism spectrum disorder (ASD) and could negatively affect family functioning and school and social competence. The aim of the present study was to investigate the relationship between aggressive behavior, such as self-aggression and other-aggression, with verbal communication ability and IQ level in children with ASD. The sample examined in this study included 88 children with a diagnosis of ASD. For the purposes of our study, much attention was focused on individual items of the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview–Revised that were useful to evaluate the aggressive behavior. We have not found any association between aggressive behavior (other-aggression and self-aggression) and the absence of language or low IQ in children with ASD. Thus, the degree of severity of autism is probably the most important risk factor for this behavior

Controlling and Phase-Locking a THz Quantum Cascade Laser Frequency Comb by Small Optical Frequency Tuning

Full phase control of terahertz (THz)-emitting quantum cascade laser (QCL) combs has recently been demonstrated, opening new perspectives for even the most demanding applications. In this framework, simplifying the set-ups for control of these devices will help to accelerate their spreading in many fields. This study reports a new way to control the emission frequencies of a THz QCL comb by small optical frequency tuning (SOFT), using a very simple experimental setup, exploiting the incoherent emission of an ordinary white light-emitting diode. The slightly perturbative regime accessible in these conditions allows tweaking the complex refractive index of the semiconductor without destabilizing the broadband laser gain. The SOFT actuator is characterized and compared to another actuator, the QCL driving current. The suitability of this additional degree of freedom for frequency and phase stabilization of a THz QCL comb is shown and perspectives are discussed.ISSN:1863-8880ISSN:1863-889

Sieroprevalenza dell’infezione da Human Bocavirus (HBoV) nella popolazione generale pugliese

Obiettivi specifici Human Bocavirus (HBoV), un nuovo parvovirus umano identificato per la prima volta nel 2005 in campioni respiratori, è associato a infezioni del basso tratto delle vie respiratorie (IBVR). Il suo ruolo di HBoV nella patogenesi di queste malattie rimane ancora tuttavia in gran psconosciuto e molto poco si sa sulla sua epidemiologia.diffusione. Scopo del nostro studio è stato di valutare la sieroprevalenza dell’HBoV nella popolazione generale pugliese, Per scoprire l'importanza del HBoV come agente infettivo nella popolazione generale in Puglia, è stato condotto uno studio di sieroprevalenza utilizzando come antigeni le proteine ricombinanti del capside VP2come antigene.. Materiali e Metodi Nel periodoTra giugno 09 e -maggio 10 sono stati raccolti collezionati 1058 campioni di siero provenienti da soggetti delladi popolazione generale pugliese provenienti da centri di analisi cliniche e ospedali regionali. e raccolti a scopo diagnostico o accertamenti di routine. La determinazione degli anticorpi anti-HBoV è stata eseguita con una nuova metodica ELISA standardizzata per il dosaggio delle IgG anti-VP2. La proteina VP2 del capside di HBoV (viruslike particle, VLP) è stata espressa ed ottenuta in cellule di insetto high-5 mediante il sistema baculovirus ricombinante “bacVP2/HBoV”. L’antigenicità delle VLP è stata convalidata da studi precedenti (Lindner J, et al. JID 2008;198:1677-84). I campioni di siero sono stati diluiti 1:100 e quando necessario 1:1000. Per la curvaCome standard , non essendo disponibile attualmente uno standard IgG internazionale, è stato utilizzato il siero di una paziente adulta sana di 49 anni risultata positiva per HBoV con tramite PCR. I dati sono stati elaborati con il software STATWIEW 5.1. Riassunto dei risultati La percentuale diIl 67,7% dei bambini nel primo anno di vita sono risultati positivi al virus ed il 51,1% soggetti sieropositivi è pari al 67,7% nel primo anno di vita seguito da un calo nel secondo anno. (51,1%). A partire Ddalla classe di età 2-4 anni (56,7%) la sieropositività aumenta in modo significativo raggiungendo valori estremamente elevati già a partire dalla classe di etàdai 5-9 anni (97,2%; p94%) in tutte le altrenelle successive classi di età senza alcuna differenza tra i i due sessi. Il Titolo Geometrico Medio (GMT) delle IgG, espresso come Unità Relative (UR), ha evidenziato un basso livello di anticorpi nelle classi 0-11 mesi (278,2 UR), 1 anno (205,0 UR) e 2-4 anni (247,2 UR). A partire dalla classe di età 5-9 anni è stato registrato un significativo aumento del GMT (954,0 UR; p<0,05) per poi restareche rimane elevato in tutte le altre classi di età. Conclusioni I dati ottenuti dimostrano testimoniano una elevata circolazione di di HBoV nella popolazione generale; , infatti la maggior parte dei bambini già dall’età di 5-9 anni sono risultati esposti, e suggeriscono unaa dimostrazione di una diffusione ubiquitaria ubiquitarietà nella circolazione del virus. I bambini in età pediatrica sembrano essere quelli maggiormente esposti alle infezioni da HBoV. Ulteriori studi sono necessari sia per poter definire più chiaramente l’epidemiologia del virus oltre che la patogenesi, soprattutto il suo ruolo nelle infezioni IBVR