4,827 research outputs found
Dispersal of larval and juvenile seabream: Implications for Mediterranean marine protected areas
In the marine context, information about dispersal is essential for the design of networks of marine protected areas (MPAs). Generally, most of the dispersal of demersal fishes is thought to be driven by the transport of eggs and larvae in currents, with the potential contribution of dispersal in later life stages relatively minimal.Using otolith chemistry analyses, we estimate dispersal patterns across a spatial scale of approximately 180. km at both propagule (i.e. eggs and larvae) and juvenile (i.e. between settlement and recruitment) stages of a Mediterranean coastal fishery species, the two-banded seabream Diplodus vulgaris. We detected three major natal sources of propagules replenishing local populations in the entire study area, suggesting that propagule dispersal distance extends to at least 90. km. For the juvenile stage, we detected dispersal of up to 165. km. Our work highlights the surprising and significant role of dispersal during the juvenile life stages as an important mechanism connecting populations. Such new insights are crucial for creating effective management strategies (e.g. MPAs and MPA networks) and to gain support from policymakers and stakeholders, highlighting that MPA benefits can extend well beyond MPA borders, and not only via dispersal of eggs and larvae, but also through movement by juveniles
The use of Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICPMS) in the study of Cultural Heritage
Several analytical techniques are actually employed for the study of Cultural Heritage and permit to identify production methodologies, constituent materials, degradation products, dating and provenance of the objects examined; elemental analyses provide precious information to archaeologists, art historians, restorers and analysts, opening a door into the past. Those techniques capable of ensuring versatility of application, sensitivity and non-destructive or micro-invasive analysis are generally requested. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICPMS), by virtue of its effective lateral resolution, sensitivity to most elements and capacity of outdoing limitations due to the low quantity of accessible samples, fulfils these requirements. Multivariate statistical techniques applied to the elemental data permit classification and provenance of artistic objects and allow to confute or confirm historical hypotheses. In the present work several case studies, addressed recently by the authors concerning objects of artistic and historical value, are outlined: pottery and glazes of Vesuvian area (Campania, Italy), fibulae of Egnatia (Puglia, Italy), inks of painting of Sant’Irene by Giuseppe Verrio and lime mortars from Siponto (Puglia, Italy). For each of the presented activity, results, advantages and drawbacks of the LA-ICPMS were discussed
Accuracy improvement in the TDR-based localization of water leaks
A time domain reflectometry (TDR)-based system for the localization of water leaks has been recently developed by the authors. This system, which employs wire-like sensing elements to be installed along the underground pipes, has proven immune to the limitations that affect the traditional, acoustic leak-detection systems. Starting from the positive results obtained thus far, in this work, an improvement of this TDR-based system is proposed. More specifically, the possibility of employing a low-cost, water-absorbing sponge to be placed around the sensing element for enhancing the accuracy in the localization of the leak is addressed. To this purpose, laboratory experiments were carried out mimicking a water leakage condition, and two sensing elements (one embedded in a sponge and one without sponge) were comparatively used to identify the position of the leak through TDR measurements. Results showed that, thanks to the water retention capability of the sponge (which maintains the leaked water more localized), the sensing element embedded in the sponge leads to a higher accuracy in the evaluation of the position of the leak
Effects of boundary conditions on irreversible dynamics
We present a simple one-dimensional Ising-type spin system on which we define
a completely asymmetric Markovian single spin-flip dynamics. We study the
system at a very low, yet non-zero, temperature and we show that for empty
boundary conditions the Gibbs measure is stationary for such dynamics, while
introducing in a single site a condition the stationary measure changes
drastically, with macroscopical effects. We achieve this result defining an
absolutely convergent series expansion of the stationary measure around the
zero temperature system. Interesting combinatorial identities are involved in
the proofs
ARCHAEOLOGICAL MATERIALS FROM GABII (CENTRAL ITALY): KNOWLEDGE OF OFFERINGS AND RITUALS AT THE INFANT BURIALS THROUGH AN INTEGRATED APPROACH
The ancient Latin city of Gabii is situated 18 km (11.2 miles) to the east of Rome (Central
Italy) along the modern Via Prenestina. Gabii was a renowned city in Roman times,
particularly during the Republican period and there are various influences in the site that can
be identified in Roman culture itself. Gabii is also one of the most significant and important
archaeological sites in the territory of the Municipality of Rome and due to its
characteristics, it represents today an extraordinary research context. From the excavations
carried out in the past it is possible to see how, under the soil, the main structures and
buildings of the ancient city are still largely preserved. Among the various testimonies of the
past, the tombs, and the micro and macro remains that these contain, represent an
opportunity to investigate such practices in the context of Early Iron Age and Orientalizing
Latium. In particular, the finds from the Area D baby burials of Gabii enriched the existing
dataset so far significantly, allowing us to explore funerary ritual behavior in a more
systematic way.
This work reports the results of the detailed examination of four tombs (Tombs 30, 50, 51
and 52) of archaeological site. The field strategy for the excavation of the tombs was geared
from the start towards both the systematic retrieval of archaeobotanical and
zooarchaeological remains and the sampling for organic residue analysis. Aiming for total
recovery, the sediments from the tomb fills were sifted in their entirety as their stratigraphic
excavation progressed, and samples were taken for flotation. This careful screening allowed
for the detection of concentrations of organic material that represent plant and/or animal
depositions. The excavation and removal of the grave goods was carried out following strict
protocols for residue sampling, minimizing the risk of organic contamination. Samples were
analysed by High Temperature Gas Chromatography/Mass Spectrometry (HTGC/MS) and
Gas chromatography/Combustion/Isotope ratio mass spectrometry (GC-C-IRMS). For each
burial, a subset of vessels including both closed and open shapes was selected, such as cups,
open bowl without foot, amphoretta, amphora with dots, Kantharos, plate on a foot, olla,
and olpe in bucchero.
The results demonstrate the still largely unexploited potential of this sort of integrated
studies, encouraging us to expand the application of chemical methods to contexts from
other well–controlled excavations
Bioactive potential of two marine picocyanobacteria belonging to Cyanobium and Synechococcus genera
Coccoid cyanobacteria produce a great variety of secondary metabolites, which may have useful properties, such as antibacterial, antiviral, anticoagulant or anticancer activities. These cyanobacterial metabolites have high ecological significance, and they could be considered responsible for the widespread occurrence of these microorganisms. Considering the great benefit derived from the identification of competent cyanobacteria for the extraction of bioactive compounds, two strains of picocyanobacteria (coccoid cyanobacteria < 3 µm) (Cyanobium sp. ITAC108 and Synechococ-cus sp. ITAC107) isolated from the Mediterranean sponge Petrosia ficiformis were analyzed. The biological effects of organic and aqueous extracts from these picocyanobacteria toward the nauplii of Artemia salina, sea urchin embryos and human cancer lines (HeLa cells) were evaluated. Methanolic and aqueous extracts from the two strains strongly inhibited larval development; on the contrary, in ethyl acetate and hexane extracts, the percentage of anomalous embryos was low. Moreover, all the extracts of the two strains inhibited HeLa cell proliferation, but methanol extracts exerted the highest activity. Gas chromatography–mass spectrometry analysis evidenced for the first time the presence of β-N-methylamino-L-alanine and microcystin in these picocyanobacteria. The strong cytotoxic activity observed for aqueous and methanolic extracts of these two cyanobacteria laid the foundation for the production of bioactive compounds of pharmacological interest
hMENA11a contributes to HER3-mediated resistance to PI3K inhibitors in HER2-overexpressing breast cancer cells.
Human Mena (hMENA), an actin regulatory protein of the ENA/VASP family, cooperates with ErbB receptor family signaling in breast cancer. It is overexpressed in high-risk preneoplastic lesions and in primary breast tumors where it correlates with HER2 overexpression and an activated status of AKT and MAPK. The concomitant overexpression of hMENA and HER2 in breast cancer patients is indicative of a worse prognosis. hMENA is expressed along with alternatively expressed isoforms, hMENA11a and hMENAΔv6 with opposite functions. A novel role for the epithelial-associated hMENA11a isoform in sustaining HER3 activation and pro-survival pathways in HER2-overexpressing breast cancer cells has been identified by reverse phase protein array and validated in vivo in a series of breast cancer tissues. As HER3 activation is crucial in mechanisms of cell resistance to PI3K inhibitors, we explored whether hMENA11a is involved in these resistance mechanisms. The specific hMENA11a depletion switched off the HER3-related pathway activated by PI3K inhibitors and impaired the nuclear accumulation of HER3 transcription factor FOXO3a induced by PI3K inhibitors, whereas PI3K inhibitors activated hMENA11a phosphorylation and affected its localization. At the functional level, we found that hMENA11a sustains cell proliferation and survival in response to PI3K inhibitor treatment, whereas hMENA11a silencing increases molecules involved in cancer cell apoptosis. As shown in three-dimensional cultures, hMENA11a contributes to resistance to PI3K inhibition because its depletion drastically reduced cell viability upon treatment with PI3K inhibitor BEZ235. Altogether, these results indicate that hMENA11a in HER2-overexpressing breast cancer cells sustains HER3/AKT axis activation and contributes to HER3-mediated resistance mechanisms to PI3K inhibitors. Thus, hMENA11a expression can be proposed as a marker of HER3 activation and resistance to PI3K inhibition therapies, to select patients who may benefit from these combined targeted treatments. hMENA11a activity could represent a new target for antiproliferative therapies in breast cancer
Feasibility of a wearable reflectometric system for sensing skin hydration
One of the major goals of Health 4.0 is to offer personalized care to patients, also through real-time, remote monitoring of their biomedical parameters. In this regard, wearable monitoring systems are crucial to deliver continuous appropriate care. For some biomedical parameters, there are a number of well established systems that offer adequate solutions for real-time, continuous patient monitoring. On the other hand, monitoring skin hydration still remains a challenging task. The continuous monitoring of this physiological parameter is extremely important in several contexts, for example for athletes, sick people, workers in hostile environments or for the elderly.
State-of-the-art systems, however, exhibit some limitations, especially related with the possibility of continuous, real-time monitoring. Starting from these considerations, in this work, the feasibility of an innovative time-domain reflectometry (TDR)-based wearable, skin hydration sensing system for real-time, continuous monitoring of skin hydration level was investigated. The applicability of the proposed system was demonstrated, first, through experimental tests on reference substances, then, directly on human skin. The obtained results demonstrate the TDR technique and the proposed system holds unexplored potential for the aforementioned purposes
Proanthocyanidins from \u3cem\u3eHedysarum, Lotus\u3c/em\u3e and \u3cem\u3eOnobrychis\u3c/em\u3e spp. Growing in Sardinia and Sicily and Their Antioxidant Activity
Proanthocyanidins (PA), or condensed tannins, are a class of natural polyphenolic compounds, occurring in numerous plant species, including a number of economically significant forage legumes. These compounds are polymers of flavan-3-ols, and typically contain from 2 to 20 units. Their biological significance is still being debated and, in recent years, a great deal of attention has been focused on their role in ruminant nutrition. Evidence has indicated that PA, in a moderate concentration (0.5-5% DM), may have considerable importance in protecting dietary proteins against microbial degradation in the rumen, and in preventing bloat. The antioxidant activity (AA) is also an important feature for animal well-being (Barry & McNabb, 1999). In order to study the PA content related to the antioxidant activity, samples of Hedysarum, Lotus and Onobrychis spp. from Mediterranean environments have been considered and investigated
Noninvasive patch resonator-based measurements on cultural heritage materials
In this work, a noninvasive microwave-based system for monitoring water content in stone materials used in Cultural Heritage structures is presented. By placing a planar resonator in contact with the considered stone sample, through reflection scattering parameter measurements, it is possible to associate the resonant frequency of the resonator to the moisture content of the stone sample. In this way, an experimental relationship between resonant frequency and moisture content can be obtained. Experimental tests are carried out on two types of materials, namely gentile and carparo stones: which are typically found in Cultural Heritage structures in Southern Italy and they are particularly affected by deterioration and decay phenomena. Measurements were performed for five levels of water content of the stone samples, and the empirical relationship between each considered level of water content and the corresponding measured quantity were derived. The obtained results demonstrate that this solution appears robust
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