1,562 research outputs found
A new record of the Red swamp crayfish, Procambarus clarkii (Girard, 1852) (Crustacea Cambaridae), in Sicily, Italy
Pressure Dependence of Fragile-to-Strong Transition and a Possible Second Critical Point in Supercooled Confined Water
By confining water in nano-pores of silica glass, we can bypass the
crystallization and study the pressure effect on the dynamical behavior in
deeply supercooled state using neutron scattering. We observe a clear evidence
of a cusp-like fragile-to-strong (F-S) dynamic transition. Here we show that
the transition temperature decreases steadily with an increasing pressure,
until it intersects the homogenous nucleation temperature line of bulk water at
a pressure of 1600 bar. Above this pressure, it is no longer possible to
discern the characteristic feature of the F-S transition. Identification of
this end point with the possible second critical point is discussed.Comment: 4 pages, 3 figure
Experimental and numerical analysis of continuous RC slab strips strengthened with CFRP laminates by using the NSM technique
Os programas experimentais para o reforço à flexão de estruturas de concreto armado (CA) segundo a técnica
NSM (Near Surface Mounted, em lÃngua inglesa) com laminados de fibras de carbono (CFRP) são, em geral,
realizados com vigas simplesmente apoiadas. Deste modo, há uma carência de estudos experimentais e teóricos
sobre a redistribuição de momentos em elementos estruturais estaticamente indeterminados reforçados segundo a
técnica NSM. Assim, de forma a avaliar a influência da técnica de reforço NSM no incremento de capacidade de
carga e na redistribuição de momentos em elementos contÃnuos de CA, um programa experimental composto por
dezessete faixas de laje foi realizado, onde seis faixas de lajes foram ensaiadas sem qualquer tipo de reforço
compósito (SL15-H/HS, SL30-H/HS e SL45-H/HS), formando o conjunto de lajes de referência, e onze faixas de laje
(SL15s25-H/HS, SL15s50-H, SL30s25-H/HS, SL30s50-H/HS, SL45s25-H/HS e SL45s50-H/HS) foram reforçadas
com laminados de CFRP inseridos no concreto de recobrimento segundo a técnica NSM. Para fins de validação, os
resultados experimentais são comparados com os valores previstos pela análise efetuada com um programa de
cálculo automático baseado no método dos elementos finitos (MEF). Por fim, um estudo paramétrico composto por
288 modelos numéricos foi realizado para investigar a influência da configuração de reforço e da percentagem de
CFRP no incremento da capacidade de carga e da redistribuição de momentos em faixas de lajes reforçadas
segundo a técnica NSM. Os programas experimental e numérico referentes às faixas de laje das séries SL15-H/HS
são descritos e os resultados obtidos são apresentados e analisados neste trabalho.The experimental programs for the flexural strengthening of reinforced concrete (RC) structures using the Near
Surface Mounted (NSM) technique with Carbon Fiber Reinforced Polymer (CFRP) laminates were, in general,
conducted with simply supported beams. Therefore, there is a lack of experimental and theoretical studies on the
moment redistribution of statically indeterminate RC elements strengthened with NSM technique. Thus, in order to
assess the influence of the NSM CFRP flexural strengthening technique on the increase of the load carrying capacity
and the moment redistribution capacity of continuous RC elements, an experimental composed of seventeen RC
slab strips was carried out, in which six of the RC slabs were unstrengthened, forming a control set (SL15-H/HS,
SL30-H/HS and SL45-H/HS), and eleven slabs (SL15s25-H/HS, SL15s50-H, SL30s25-H/HS, SL30s50-H/HS,
SL45s25-H/HS and SL45s50-H/HS) were strengthened with CFRP laminates according to the NSM technique.
Furthermore, for validation purposes, the experimental results are compared with values predicted by the analysis
carried out using a FEM-based computer program. Finally, a parametric study composed of 288 numerical models is
carried out to investigate the influence of the strengthening arrangement and CFRP percentage in terms of load
carrying capacity and moment redistribution capacity of continuous RC slab strips flexurally strengthened by the
NSM technique. The experimental and numerical programs concerns to the SL15-H/HS Series are described and
the obtained results are presented and analyzed in this paper
A study of quantum well solar cell structures with bound-to-continuum transitions for reduced carrier recombination
A bound-to-continuum quantum well solar cell structure is proposed, and the band structure and absorption spectra are analyzed by the use of an eight band kâ‹…p model. The structure is based on quantum wells that only support bound states for the valence band. The absence of bound conduction band states has a number of potential advantages, including a reduction of electron trapping and, therefore, a reduction of quantum well induced photocarrier recombination due to reduced spatial overlap of the electron and hole wavefunctions.Thanks are due to the Australian Research Council for
the financial support of this research
Phytochemical profile of capsicum annuum l. Cv senise, incorporation into liposomes, and evaluation of cellular antioxidant activity
Overproduction of oxidants in the human body is responsible for oxidative stress, which is associated with several diseases. High intake of vegetables and fruits can reduce the risk of chronic diseases, as they are sources of bioactive compounds capable of contrasting the free radical effects involved in cancer, obesity, diabetes, and neurodegenerative and cardiovascular diseases. Capsicum annuum L. cv Senise is a sweet pepper that is grown in the Basilicata region (Italy). It is an important source of polyphenols, carotenoids, and capsinoids and can play a key role in human health. In this study, an ethanol extract was obtained from C. annuum dried peppers and the analysis of the phytochemical composition was performed by LC-ESI/LTQ Orbitrap/MS. The extract was incorporated into liposomes, which showed small size (~80 nm), good homogeneity, negative surface charge, and good stability in storage. The biological activity of the extract was evaluated in the human hepatoma (HepG2) cell line, used as model cells. The extract showed no cytotoxic activity and reduced the intracellular reactive oxygen species (ROS) level in stressed cells. The antioxidant activity was further improved when the extract was loaded into liposomes. Moreover, the extract promoted the expression of endogenous antioxidants, such as catalase, superoxide dismutase, and glutathione peroxidase through the Nrf-2 pathway evaluated by RT-PCR
A systematic review of the safety of lisdexamfetamine dimesylate
BACKGROUND: Here we review the safety and tolerability profile of lisdexamfetamine dimesylate (LDX), the first long-acting prodrug stimulant for the treatment of attention-deficit/hyperactivity disorder (ADHD). METHODS: A PubMed search was conducted for English-language articles published up to 16 September 2013 using the following search terms: (lisdexamfetamine OR lisdexamphetamine OR SPD489 OR Vyvanse OR Venvanse OR NRP104 NOT review [publication type]). RESULTS: In short-term, parallel-group, placebo-controlled, phase III trials, treatment-emergent adverse events (TEAEs) in children, adolescents, and adults receiving LDX were typical for those reported for stimulants in general. Decreased appetite was reported by 25-39 % of patients and insomnia by 11-19 %. The most frequently reported TEAEs in long-term studies were similar to those reported in the short-term trials. Most TEAEs were mild or moderate in severity. Literature relating to four specific safety concerns associated with stimulant medications was evaluated in detail in patients receiving LDX. Gains in weight, height, and body mass index were smaller in children and adolescents receiving LDX than in placebo controls or untreated norms. Insomnia was a frequently reported TEAE in patients with ADHD of all ages receiving LDX, although the available data indicated no overall worsening of sleep quality in adults. Post-marketing survey data suggest that the rate of non-medical use of LDX was lower than that for short-acting stimulants and lower than or equivalent to long-acting stimulant formulations. Small mean increases were seen in blood pressure and pulse rate in patients receiving LDX. CONCLUSIONS: The safety and tolerability profile of LDX in individuals with ADHD is similar to that of other stimulants
Snappy App: a mobile continuous performance test with physical activity measurement for assessing Attention Deficit Hyperactivity Disorder
A Continuous Performance Test (CPT) was incorporated into a smartphone application (App) to measure three symptom domains associated with Attention Deficit Hyperactivity Disorder (ADHD); attention, impulsivity and hyperactivity. The App was pilot tested on 11 healthy adults over three test-ing sessions. No differences in performance were found between testing ses-sions suggesting good test consistency. A decrement in performance over time was only found for one measure of attention and on one testing session. The CPT showed some sensitivity to ADHD-related symptoms where self-reported impulsive behaviour was related to the CPT measures of impulsivity and activi-ty. User acceptability was good although some design improvements were sug-gested. Further pilot testing of the App in a clinical population is needed
Distribution and natural history of Plutonium zwierleini (Chilopoda: Scolopendromorpha) in Sicily (Italy)
Plutonium zwierleini is a large plutoniumid centipede of great evolutionary interest, occurring with isolated populations along the western Mediterranean area, from Spain to Italy. Due to its rarity and the extreme paucity of available records, P. zwierleini is among the least known Mediterranean chilopods, and scarce information is currently available on its ecology and natural history. Based on an extensive sampling effort carried out in Sicily between 2022 and 2023, we here provide additional occurrence localities for the species across Sicily, and new insights into its ecology. Overall, 29 novel Sicilian records of P. zwierleini, scattered across 21 localities, were collected thus increasing its known Sicilian distribution area by 117%, and the number of localities by 110%. The species was found in a wide range of habitats such as open areas, woods, buildings, and caves, characterizing Plutonium zwierleini as a habitat generalist, whose fine ecological preferenda need to be further explored. Moreover, to explore the diet and behaviour of the species, some specimens were kept in captivity. The captive individuals fed mostly on dead or poorly mobile soft-bodied prey and inert food, without ever displaying predatory behaviour; this suggests that, contrarily to what is currently assumed, P. zwierleini might be a scavenger rather than a predator. The potential distribution of Plutonium zwierleini in Sicily was inferred based on georeferenced occurrence records and climatic variables. The implemented MaxEnt model forecasts the possible occurrence of P. zwierleini on the whole island, with the single exception of its south-easternmost part, possibly due to the local pattern of precipitation seasonality. We hope that the present work might pave the way for further surveys aimed at a better understanding of the ecology of Plutonium zwierleini and the collection of new data in the other regions inhabited by this secretive species
The Endangered Sardinian Grass Snake: Distribution Update, Bioclimatic Niche Modelling, Dorsal Pattern Characterisation, and Literature Review
Antioxidant and antisenescence effects of bergamot juice
Aging is one of the main risk factor for the onset of cardiovascular diseases; one of the possible explanations could be linked to the age-associated overproduction of free radicals. This increase of oxidative stress can be overcome with a high intake of food antioxidants. In this context, a number of studies have been addressed to assess the antiaging potential of natural antioxidant compounds. Recently, it has been shown that the juice of bergamot (Citrus bergamia Risso et Poiteau), a fruit mostly produced in the Ionian coastal areas of Southern Italy (Calabria), is a valuable source of health-promoting constituents with, among other, antioxidant properties. In order to investigate the potential antiaging effects of this Mediterranean natural antioxidant source, bergamot juices of three different cultivars ("fantastico," "femminello," and "castagnaro") were herein characterized by the mean of high-performance liquid chromatography-photodiode array-electrospray ionization-tandem mass spectrometry. Then, juices were investigated for the evaluation of total polyphenolic and flavonoid contents, cell-free model antioxidant activities, and in vitro antiaging properties on two different cellular models of induced myocardial senescence. The best performing juice was also assessed in vivo. The phytochemical profiles confirmed that juices were rich in flavonoids, both flavone and flavanone glycosides. In addition, two limonoid glycosides were also identified in all cultivars. Each cultivar showed different phenolic and flavonoid contents. In tube results showed the juice robust antioxidant activities that correlate with their phenolic and flavonoid contents. Moreover, for the first time, the ability of juice to counteract the chemical-induced senescence was here demonstrated in both cellular models. Lastly, the in vivo data obtained from mouse hearts evidenced an increase in transcription of genes involved in antiaging and antioxidant responses. The overall results suggest that bergamot juice exerts antioxidant and antisenescence effects, making it useful for nutraceutical purposes
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