Time Evolution of Non-Lethal Infectious Diseases: A Semi-Continuous Approach

A model describing the dynamics related to the spreading of non-lethal infectious diseases in a fixed-size population is proposed. The model consists of a non-linear delay-differential equation describing the time evolution of the increment in the number of infectious individuals and depends upon a limited number of parameters. Predictions are in good qualitative agreement with data on influenza.Comment: 21 page

New Surgical Frontiers for Nutrition in Children

Nutrition in pediatric age, if properly adapted to the various developmental phases, can be considered the first prevention tool for the most common pathologies of this age [...

Preventing and Responding to Juvenile Crime: Importance of Intervention and Rehabilitation

With about 2.1 million juveniles arrested per year, it is important for researchers and juvenile justice employees to consider, protect and maximize the full potential of juveniles from their early adolescence up until release from detention centers or foster care. This paper highlights early traits and behaviors consistent in juveniles who commit crime as well as factors that may contribute to crime. While focusing on early indicators that may lead to juvenile crime, the paper also discusses rehabilitation and intervention after juvenile crime has been committed. After discussing the research on preventing and responding to juvenile crime, the paper outlines careers within the scope of juvenile crime and how these careers are ongoing and developing to provide maximum treatment and positive outcomes for the youth. The careers reviewed in this paper range from preliminary intervention careers, such as social workers for the Department of Children and Families, to juvenile probation officers assigned after a juvenile appears in court. Overall this paper discusses why juvenile crime occurs and how we can work to provide treatment and rehabilitation and decrease reoffending

Morbo di Hirschsprung: approccio diagnostico differenziato

La diagnosi del morbo di Hirschsprung (MH) si esegue con esami per immagini (clisma opaco), tests funzionali come la Manometria Ano-Rettale (MAR) e studi immunoistochimici su biopsie rettali per suzione (BRS). L’approccio diagnostico più appropriato è ancora discusso dato che tutti i tests producono falsi positivi e falsi negativi ed ognuno presenta vantaggi e svantaggi. Lo scopo di questo lavoro è quello di valutare l’efficacia di un approccio diagnostico differenziato in base all’età per i pazienti con sospetto di MH. Materiali e Metodi: da Gennaio 2005 a Giugno 2007 sono stati esaminati tutti i pazienti giunti all’osservazione chirurgica per sospetto di MH. I pazienti sono stati divisi in due gruppi: A (età inferiore ad 1 anno) e B (età superiore ad 1 anno). I pazienti del gruppo A sono stati sottoposti a BRS e clisma opaco (CO), mentre quelli del gruppo B sono stati sottoposti a MAR per lo studio del tono dello sfintere anale interno e per la ricerca del Riflesso Inibitore Retto-Anale (RIRA), poi in base all’esito della MAR sono stati divisi in 5 sottogruppi ed hanno ricevuto un iter diagnostico-terapeutico diverso: B1, tono normale e RIRA presente (pulizia intestinale con soluzione a base di polietilenglicole (PEG) ad alto peso molecolare poi lassativi orali e clisteri settimanali per 2 mesi); B2, ipertono dello sfintere anale interno e RIRA presente (anestetico locale per 8 settimane associato al lassativo orale e clisteri settimanali per 2 mesi); B3, pazienti non collaboranti (sottoposti a BRS); B4, RIRA assente/dubbio (sottoposti a BRS e CO); B5, RIRA presente, ma scarsi risultati dopo terapia medica al follow up di 6 mesi (sottoposti a BRS e CO). I pazienti con BRS positive (aumentata attività dell’Acetilcolinesterasi associata ad assenza dei gangli) sono stati sottoposti ad intervento chirurgico di Pull-Through ano-rettale per via laparoscopica sec. Georgeson. Tutti i pazienti hanno seguito un follow up a 2 mesi (positivo se evacuazioni settimanali > 5 in corso di trattamento), poi a 6 mesi (positivo se evacuazioni settimanali > 3, senza trattamento). Risultati: I pazienti arruolati per questo studio sono stati 100 (55 maschi, 45 femmine), di cui 14 (età media 2 mesi) sono stati inseriti nel gruppo A, gli altri 86 (età media 6 anni) nel gruppo B. Il CO nei pazienti del gruppo A ha mostrato dilatazione del colon con cono di transizione in due casi, mentre le biopsie rettali per suzione hanno evidenziato assenza di cellule gangliari ed aumento delle fibre colinergiche nel 50% dei pazienti. Nel gruppo B1 sono stati inclusi 40 pazienti, 24 nel gruppo B2, i non collaboranti sono stati 4, mentre 18 sono stati inclusi nel gruppo B4 ed uno solo nel B5. Nel gruppo B sono stati eseguiti 19 CO (gruppi B4 e B5) e BRS in 23 pazienti (gruppi B3, B4 e B5). Al CO sono stati evidenziati dolicolon e megaretto nel 89% dei casi, mentre le BRS hanno evidenziato assenza di gangli ed aumento delle fibre colinergiche in 3 bambini (13%). L’intervento chirurgico è stato eseguito in 6 bambini del gruppo A e 2 del gruppo B, gli altri sono stati trattati altrove. Conclusioni: La MAR è un esame semplice e poco invasivo per studiare il meccanismo della defecazione nei bambini di età superiore ad un anno. L’approccio diagnostico differenziato in base all’età permette di selezionare i casi da sottoporre alle BRS e CO, esami invasivi che possono presentare complicanze. L’esecuzione delle BRS in casi selezionati permette di avere alti valori di positività (50% e 13%) evitando di estendere la procedura a tutti i pazienti con sospetto di MH

Treatment of post-traumatic parotid gland fistula in children

Post-traumatic fistula of the parotid gland is rare especially in children and the treatment is not established: surgery, drugs or conservative treatment. The authors present the case of a 3-year-old child with cutaneous-parotid fistula following penetrating trauma of the face. A conservative treatment with compression dressings was used and one month later a complete closure of the fistula was obtained. In this case a conservative approach should be considered because the part of the fistulized gland goes into atrophy and allows the closure of the fistula

Aeroelastic Stability Assessment Of a CS-25 Category Aircraft Equipped With Multi-Modal Wing Morphing Devices

Morphing wing structures have the greatest ambition to dramatically im-prove aircraft aerodynamic performance (less fuel consumption) and reduce aerodynamic noise. Several studies in the literature have shown their potential for increased aerodynamic efficiency across nearly all flight conditions, en-hanced aircraft maneuverability and control effectiveness, decreased take-off/landing length, reduced airframe noise, etc. However, despite a long herit-age of research, morphing wing technology has yet to be approved by the Euro-pean Aviation Safety Authority (EASA) for use in commercial aviation. Models and approaches capable to predict the aeroelastic impact of a morphing wing still need to be matured to safely alter design and operation of future genera-tions of aircraft. Additionally, a number of practical challenges remain to be addressed in the suitable materials, systems reliability, safety and maintenance. Due to the reduced stiffness, increased mass and increased Degree Of Freedom (DOF) with respect to conventional wings, these mechanical systems can cause significant reduction of aircraft flutter margins. This aspect requires dedicated aeroelastic assessments since the early stages of the design process of such an innovative wing. Flutter boundaries predictions need sensitivity anal-yses to evaluate bending/torsional stiffness and inertial distribution variability ranges of the aircraft wing equipped with the morphing wing devices. In such a way, aeroelastic assessments become fundamental to drive a balance between weight and stiffness of the investigated adaptive systems. Furthermore, in pseu-do rigid-body mechanisms-based morphing structures, the inner kinematics is so important that its faults may compromise the general aircraft-level functions. Similarly to the demonstration means of safety compliance, commonly applied to aircraft control surfaces, the novel functions resulting from the integration of adaptive devices into flying aircraft thus impose a detailed examination of the associated risks. In the framework of Clean Sky 2 Airgreen 2 project, the author provides advanced aeroelastic assessments of two adaptive devices enabling the camber morphing of winglets and flaps, conceived for regional aircraft integration (EASA CS-25 category). Segmented ribs architectures ensure the transition from the baseline (or un-morphed) shape to the morphed ones, driven by em-bedded electromechanical actuators. Some of the advantages resulting from the combination of the two aforementioned morphing systems are wing load con-trol, lift-over-drag ratio increase and root bending moment alleviation. The aircraft aeroelastic model was generated by means of the proprietary code SANDY 3.0. Then, the same code was adopted to solve the aeroelastic stability equa-tions through theoretical modes association in frequency domain. To carry out multi-parametric flutter analyses (P-K continuation method), the actuation lines stiffness and winglet/flap tabs inertial parameters were considered in combina-tion each other. Nominal operative conditions as well as systems malfunction-ing or failures were examined as analyses cases of the investigated morphing devices, together with actuators free-play conditions. Proper design solutions were suggested to guarantee flutter clearance in accordance with aircraft stabil-ity robustness with respect to morphing systems integration, evaluated through a combination of “worst cases” simulating the mutual interaction among the adaptive systems. The safety-driven design of the morphing wing devices required also a thorough examination of the potential hazards resulting from operational faults involving either the actuation chain, such as jamming, or the external interfaces, such as loss of power supplies and control lanes, and both. The main goal was to verify whether the morphing flap and winglet systems could comply with the standard civil flight safety regulations and airworthiness requirements (EASA CS25). More in detail, a comprehensive study of systems functions was firstly qualitatively performed at both subsystem and aircraft levels to identify poten-tial design faults, maintenance and crew faults, as well as external environment risks. The severity of the hazard effects was thus determined and then ranked in specific classes, indicative of the maximum tolerable probability of occurrence for a specific event, resulting in safety design objectives. Fault trees were final-ly produced to assess the compliance of the system architectures to the quanti-tative safety requirements resulting from the FHAs

HDAC4 regulates skeletal muscle regeneration via soluble factors

Skeletal muscle possesses a high ability to regenerate after an insult or in pathological conditions, relying on satellite cells, the skeletal muscle stem cells. Satellite cell behavior is tightly regulated by the surrounding microenvironment, which provides multiple signals derived from local cells and systemic factors. Among epigenetic mechanisms, histone deacetylation has been proved to affect muscle regeneration. Indeed, pan-histone deacetylase inhibitors were found to improve muscle regeneration, while deletion of histone deacetylase 4 (HDAC4) in satellite cells inhibits their proliferation and differentiation, leading to compromised muscle regeneration. In this study, we delineated the HDAC4 function in adult skeletal muscle, following injury, by using a tissue-specific null mouse line. HDAC4 resulted crucial for skeletal muscle regeneration by mediating soluble factors that influence muscle-derived cell proliferation and differentiation. These findings add new biological functions to HDAC4 in skeletal muscle that need considering when administering histone deacetylase inhibitors