205 research outputs found
Concept design and feasibility study of propulsion system for yacht: innovative hybrid propulsion system fueled by methanol
Preliminary Investigation of a Multi-MW Solid Oxide Fuel Cell Power Plant to be Installed on Board a Cruise Ship
The potential role of preventive and therapeutic immunonutrition strategies for pediatric food allergy: A mini-review
: Food allergy (FA) represents one of the main chronic conditions of the pediatric population. The gut microbiome (GM)-immune system axis is a milestone in affecting FA susceptibility. The dynamic and bidirectional crosstalk between the GM and immune system starts early in life, and it is deeply modulated during the first 1,000 days of life. Nutritional factors during this crucial period mainly influence the proper GM-immune system development and function across the lifespan, with potential beneficial or detrimental effects on health status. Immunonutrition strategies, applied from conception, could represent an innovative target for prevention and treatment of pediatric FA. Here we described the potential role of preventive and therapeutic immunonutrition strategies for pediatric FA, highlighting putative future perspectives in this field
Digital holographic microscopy for the evaluation of human sperm structure
The morphology of the sperm head has often been correlated with the outcome
of in vitro fertilization (IVF), and has been shown to be the sole parameter in
semen of value in predicting the success of intracytoplasmic sperm injection
(ICSI) and intracytoplasmic morphologically selected sperm injection (IMSI). In
this paper, we have studied whether Digital Holographic (DH) microscopy may be
useful to obtain quantitative data on human sperm head structure and compared
this technique to high power digitally enhanced Nomarski microscope. The main
advantage of DH is that a high resolution 3-D quantitative sample imaging may
be obtained thorugh numerical refocusing at different object planes without any
mechanical scanning. We show that DH can furnish useful information on the
dimensions and structure of human spermatozoo, that cannot be revealed by
conventional phase contrast microscopy. In fact, in this paper DH has been used
to evaluate volume and indicate precise location of vacuoles, thus suggesting
its use as an additional useful prognostic quantitative tool in assisted
reproduction technology (ART)
The status of sustainable social innovation in Malta
Governments are increasingly using social innovation to stimulate economic growth and address social issues sustainably. Unfortunately, due to its size, Malta faces a very different challenge to sustainably kick-start high-value-added innovative ecosystems compared to larger states. This is due to a number of issues, including diseconomies of scale, that tend to impede conventional innovation policy efforts. Based on grassroots data, this paper presents the results of a study which determined the status of social innovation in Malta and presents a few recommended measures that can be implemented in order to stimulate social innovation sustainably in Malta and possibly in similar small jurisdictions.peer-reviewe
Preliminary Investigation of a Multi-MW Solid Oxide Fuel Cell Power Plant to be Installed on Board a Cruise Ship
As the use of both clean energy technologies and alternative fuels in the maritime sector is spreading, studies dealing with the installation of multi-MW power generation plants on board ships have been increasing. Considering this, the present work proposes a 12 MW Solid Oxide Fuel Cell (SOFC) to be installed on board a cruise ship of about 175000 gross tonnes, 345 m length, and powered by Liquefied Natural Gas (LNG). It is supposed that the SOFC generates electrical energy and provides part of the thermal power demand by integrating a heat recovery system. A zero-dimensional (0D) Aspen Plus model has been developed to optimize the onboard layout and to predict the performance of the integrated power plant. Specific parameters, such as the fuel utilisation factor, the pre-heated air temperature, the anodic recycle flow rate, and the exhaust gas temperature, have been manipulated to evaluate the overall efficiency of the integrated power plant under different operating conditions. The model has been validated by comparing the results obtained with data from literature and commercial SOFC modules. A layout configuration of the SOFC plant is suggested and the performances are investigated by varying the efficiency in the range of 60-40%
Sleep Disorders and Psychological Profile in Oral Cancer Survivors: A Case-Control Clinical Study
Quality of sleep (QoS) and mood may impair oral cancer survivors’ wellbeing, however few evidences are currently available. Therefore, we aimed to assess the prevalence of sleep disorders, anxiety and depression among five-year oral cancer survivors (OC survivors). 50 OC survivors were compared with 50 healthy subjects matched for age and sex. The Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the Hamilton Rating Scales for Depression and Anxiety (HAM-D, HAM-A), the Numeric Rating Scale (NRS), the Total Pain Rating Index (T-PRI) were administered. The global score of the PSQI, ESS, HAM-A, HAM-D, NRS, T-PRI, was statistically higher in the OC survivors than the controls (p-value: <0.001). QoS of OC survivors was significantly impaired, especially with regard to some PSQI sub-items as the subjective sleep quality, sleep latency and daytime dysfunction (p-value: 0.001, 0.029, 0.004). Moreover, poor QoS was negatively correlated with years of education (p-value: 0.042 *) and positively correlated with alcohol consumption (p-value: 0.049 *) and with the use of systemic medications (p-value: 0.044 *). Sleep disorders and mood disorders are common comorbidities in OC survivors; therefore, early assessment and management before, during and after treatment should be performed in order to improve the quality of life of OC survivors
EVOLUTIONARY ADAPTATIONS IN ANTARCTIC FISH: THE OXYGEN-TRANSPORT SYSTEM
Understanding molecular adaptations evolved in response to environmental temperature changes is essential, because temperature affects the kinetic energy of molecules and modifies molecular interactions, macromolecular stability/functioning and membrane features. Environmental oxygen availability may also play an important role in the evolution of polar marine organisms, as suggested by the physiological and biochemical strategies adopted by these organisms to acquire, deliver and scavenge oxygen.This review summarises the current knowledge on the structure and function of hemoglobins of fish living in Antarctic habitats. The variety of adaptations underlying the ability of Antarctic fish to survive at temperatures permanently close to freezing is unique among teleosts. The dominant perciform suborder Notothenioidei affords an excellent study group for elaborating the evolution of biochemical adaptation to temperature. The availability of notothenioid taxa living in a wide range of latitudes (Antarctic, sub-Antarctic, and temperate regions) offers a remarkable opportunity to study the physiological and biochemical characters gained and, conversely, lost in response to cold and to reconstruct the likely evolutionary events modulating the ability to carry oxygen in freezing habitats. Although oxygen can be transported in freely dissolved form most animals rely on one or more protein carriers to deliver it to the respiring tissues. Compared to temperate and tropical species, high-Antarctic notothenioids have evolved reduced hemoglobin concentration/multiplicity. The Antarctic family Channichthyidae (the notothenioid crown group) is devoid of hemoglobin. All extant icefish species lack hemoglobin and many have lost myoglobin expression. In these species, oxygen delivery to tissues occurs by transport of the gas physically dissolved in the plasma.ADAPTACIONES EVOLUTIVAS EN PECES ANTÁRTICOS: EL SISTEMA DE TRANSPORTE DE OXÍGENO. Comprender las adaptaciones moleculares que han evolucionado en respuesta a los cambios de temperatura del medio ambiente es esencial, porque la temperatura afecta la energía cinética de las moléculas y modiica las interacciones moleculares, la estabilidad de las macromoleculares, sus características y el funcionamiento de la membrana. La disponibilidad de oxígeno ambiental desempeña un papel importante en la evolución de los organismos marinos polares, como se evidencia en las estrategias isiológicas y bioquímicas adoptadas por estos organismos para adquirir, gastar y usar oxígeno. Esta revisión resume el conocimiento actual sobre la estructura y función de la hemoglobina de los peces que viven en hábitats antárticos. La amplia variedad de adaptaciones que permiten que los peces antárticos tengan la capacidad para sobrevivir de forma permanente en temperaturas cerca de la congelación es única entre los teleósteos. El suborden Notothenioidei, perteneciente a los Perciformes, es un excelente grupo para el estudio de la evolución y adaptación bioquímica a la temperatura. La gran variedad de taxones de nototénidos que viven en una amplia variedad de latitudes (Antártida, sub-antárticas, y las regiones templadas) ofrece una oportunidad extraordinaria para estudiar las características isiológicas y bioquímicas adquiridas y perdidas por este grupo en respuesta al frío, además de la posibilidad de reconstruir los eventos más probables que direccionaron la evolución de la capacidad de transportar oxígeno en hábitats polares. Aunque el oxígeno puede ser transportado en su forma libre disuelta, la mayoría de los animales dependen de una o más proteínas para entregarlo a los tejidos para la respiración. En comparación con especies de zonas templadas y tropicales, los nototenoideos de la alta Antártida han evolucionado reduciendo la concentración y multiplicidad de hemoglobina. La familia antártica Channichthyidae (el grupo con corona de los Nototénidos) carece de la hemoglobina. Todas las especies de peces existentes que viven en el hielo carecen de hemoglobina y muchas han perdido la expresión de la mioglobina. En estas especies, el aporte de oxígeno a los tejidos se produce por el transporte del gas físicamente disuelto en el plasma. Palabras clave: Antártida; adaptaciones al frio; evolución; hemoglobina.ADAPTAÇÕES EVOLUTIVAS EM PEIXES ANTÁTRTICOS: O SISTEMA DE TRANSPORTE DE OXIGÊNIO. Compreender as adaptações moleculares envolvidas na resposta às mudanças na temperatura ambiental é essencial, pois a temperatura afeta a energia cinética das moléculas e modiica as interações moleculares, a estabilidade/funcionamento das macromoléculas e as características da membrana. A disponibilidade de oxigênio no ambiente pode também ter um importante papel na evolução dos organismos marinhos polares, como indicado pelas estratégias isiológicas e bioquímicas adotadas por estes organismos para adquirir, transportar e trocar oxigênio. Esta revisão resume o conhecimento atual da estrutura e funcionamento das hemoglobinas de peixes que ocorrem em ambientes Antárticos. A diversidade de adaptações que sustentam a habilidade de peixes antárticos sobreviverem em temperaturas permanentemente próximas do congelamento é única entre os teleósteos. A dominante sub-ordem Perciforme Notothenioidei apresenta-se como um excelente grupo de estudo para melhorar o conhecimento sobre a evolução das adaptações bioquímicas à temperatura. A ocorrência de nototenióides em uma ampla variedade de latitudes (Antártica, sub-Antártica e regiões temperadas) oferece uma oportunidade notável para estudar as características isiológicas e bioquímicas obtidas e, por outro lado, perdidas em resposta ao frio, além de tornar possível a reconstrução dos eventos evolutivos que provavelmente modularam a habilidade desses peixes de transportar oxigênio em ambientes extremamente frios. Embora o oxigênio possa ser transportado livremente na sua forma dissolvida, a maioria dos animais depende de um ou mais tipos de proteínas carreadoras para entregar o oxigênio aos tecidos. Quando comparadas às espécies temperadas e tropicais, os nototenióides da região Antártica, propriamente dita, desenvolveram reduzida concentração/multiplicidade de hemoglobinas. A família de peixes Antárticos Channichthyidae (crown group nototenióide) não apresenta hemoglobina. Todas as espécies de iceish (peixes-do-gelo) não possuem hemoglobinas e muitas também não produzem mioglobinas. Nessas espécies, o transporte de oxigênio aos tecidos ocorre através do gás isicamente dissolvido no plasma. Palavras-chave: Antártica; adaptações ao frio; evolução; hemoglobina
- …