393 research outputs found
Can a microscopic stochastic model explain the emergence of pain cycles in patients?
A stochastic model is here introduced to investigate the molecular mechanisms
which trigger the perception of pain. The action of analgesic drug compounds is
discussed in a dynamical context, where the competition with inactive species
is explicitly accounted for. Finite size effects inevitably perturb the
mean-field dynamics: Oscillations in the amount of bound receptors
spontaneously manifest, driven by the noise which is intrinsic to the system
under scrutiny. These effects are investigated both numerically, via stochastic
simulations and analytically, through a large-size expansion. The claim that
our findings could provide a consistent interpretative framework to explain the
emergence of cyclic behaviors in response to analgesic treatments, is
substantiated.Comment: J. Stat. Mech. (Proceedings UPON2008
Rapporto tecnico sulla valutazione della biomassa ittioplanctonica mediante l'utilizzo del Multi Plankton Sampler (MPS)
Il piano di campionamento della campagna oceanografica BANSIC'14, condotta a bordo della N/O "URANIA" dal 22 Luglio al 9 Agosto 2014, lungo transetti sotto costa e a largo delle coste meridionali della Sicilia, ha avuto l’obiettivo generale dello studio delle relazioni tra le strutture oceanografiche a mesoscala (vortici verticali ed orizzontali, upwelling, etc.) e le strutture spaziali dei fenomeni biologici relativi ai primi anelli della catena trofica (zooplancton, distribuzione e abbondanza di larve di piccoli pelagici e grandi pelagici) (vedi Rapporto finale BANSIC 2014) per la stima dell’abbondanza dello stock riproduttore. E' una campagna di ricerca nell'ambito del WP3 del progetto SSD-Pesca, finanziato dal MIUR su fondi MISE, a supporto della pesca italiana nelle Regioni Obiettivo 1 e del progetto RITMARE (SP2_WP4_AZ2_UO04). Il campionamento ittioplanctonico è inserito anche nel piano di lavoro del progetto regionale MIPAF-FAO “MedSudMed” (“Assessment and Monitoring of the Fishery Resources and the Ecosystems in the Straits of Sicily”).
Il campionamento dell’ittioplancton, durante questa campagna, oltre ai metodi tradizionali quali le reti di tipo Bongo, ha visto l'utilizzo del Multi Plankton Sampler (MPS) MultiNet.
I campionatori ittioplanctonici hanno lo scopo di prelevare porzioni di mesozooplancton da un massimo di 100 m fino alla superficie, in quanto le uova di pesci pelagici possiedono una galleggiabilità tale che nonostante le turbolenze superficiali dell’acqua, un campionamento entro i primi metri restituisce un dato affidabile della distribuzione anche se alcune uova possono trovarsi a maggiore profondità (Ahlstrom, 1959).
Il campionatore MPS consente, a differenza di altri strumenti, di prelevare la frazione di zooplancton d'interesse con diverse modalitĂ di campionamento: orizzontale, verticale e obliquo e, allo stesso tempo, permette di campionare a differenti quote di profonditĂ .
Le informazioni così ottenute sono state utilizzate per valutare la variazione della biomassa ittioplanctonica, l'abbondanza e la composizione delle specie lungo gli strati della colonna d'acqua anche in relazione alle componenti oceanografiche.
Grazie all'utilizzo di questo strumento è possibile validare e verificare alcune informazioni e acquisirne delle nuove sull’ecologia delle specie larvali e sul mesozooplancton, sul modo in cui queste si distribuiscono lungo la colonna d'acqua e sulle interazioni intra ed interspecifiche legate anche a fattori oceanografici. Ciò consente di ottenere maggiori informazioni e contribuire al miglioramento della comprensione della biologia e dell'ecologia delle specie rinvenute e, nel contempo, approfondire e migliorare le conoscenze sugli stadi di sviluppo di uova di specie ittiche che allo stadio embrionale sono ancora poco conosciuti
Diauxie and co-utilization of carbon sources can coexist during bacterial growth in nutritionally complex environments
It is commonly thought that when multiple carbon sources are available, bacteria metabolize them either sequentially (diauxic growth) or simultaneously (co-utilization). However, this view is mainly based on analyses in relatively simple laboratory settings. Here we show that a heterotrophic marine bacterium, Pseudoalteromonas haloplanktis, can use both strategies simultaneously when multiple possible nutrients are provided in the same growth experiment. The order of nutrient uptake is partially determined by the biomass yield that can be achieved when the same compounds are provided as single carbon sources. Using transcriptomics and time-resolved intracellular 1H-13C NMR, we reveal specific pathways for utilization of various amino acids. Finally, theoretical modelling indicates that this metabolic phenotype, combining diauxie and co-utilization of substrates, is compatible with a tight regulation that allows the modulation of assimilatory pathways
When does cyclic dominance lead to stable spiral waves?
Species diversity in ecosystems is often accompanied by characteristic spatio-temporal patterns. Here, we consider a generic two-dimensional population model and study the spiraling patterns arising from the combined effects of cyclic dominance of three species, mutation, pair-exchange and individual hopping. The dynamics is characterized by nonlinear mobility and a Hopf bifurcation around which the system's four-phase state diagram is inferred from a complex Ginzburg-Landau equation derived using a perturbative multiscale expansion. While the dynamics is generally characterized by spiraling patterns, we show that spiral waves are stable in only one of the four phases. Furthermore, we characterize a phase where nonlinearity leads to the annihilation of spirals and to the spatially uniform dominance of each species in turn. Away from the Hopf bifurcation, when the coexistence fixed point is unstable, the spiraling patterns are also affected by the nonlinear diffusion
Prolonged survival in the absence of disease-recurrence in advanced-stage follicular lymphoma following chemo-immunotherapy: 13-year update of the prospective, multicenter randomized GITMO-IIL trial
Aprospective trial conducted in the period 2000-2005 showed no survival advantage for high-dose chemotherapy with rituximab and autograft (RHDS) versus conventional chemotherapy with rituximab (CHOP-R) as firstline therapy in 134 high-risk follicular lymphoma patients aged <60 years. The study has been updated at the 13-year median follow up. As of February 2017, 88 (66%) patients were alive, with overall survival of 66.4% at 13 years, without a significant difference between R-HDS (64.5%) and CHOP-R (68.5%). To date, 46 patients have died, mainly because of disease progression (47.8% of all deaths), secondary malignancies (3 solid tumor, 9 myelodysplasia/acute leukemia; 26.1% of all deaths), and other toxicities (21.7% of all deaths). Complete remission was documented in 98 (73.1%) patients and associated with overall survival, with 13- year estimates of 77.0% and 36.8% for complete remission versus no-complete remission, respectively. Molecular remission was documented in 39 (65%) out of 60 evaluable patients and associated with improved survival. In multivariate analysis, complete remission achievement had the strongest effect on survival (P<0.001), along with younger age (P=0.002) and female sex (P=0.013). Overall, 50 patients (37.3%) survived with no disease recurrence (18 CHOP-R, 32 R-HDS). This follow up is the longest reported on follicular lymphoma treated upfront with rituximab-chemotherapy and demonstrates an unprecedented improvement in survival compared to the pre-rituximab era, regardless of the use of intensified or conventional treatment. Complete remission was the most important factor for prolonged survival and a high proportion of patients had prolonged survival in their first remission, raising the issue of curability in follicular lymphoma
Seascape connectivity of European anchovy in the Central Mediterranean Sea revealed by weighted Lagrangian backtracking and bio-energetic modelling
Ecological connectivity is one of the most important processes that shape marine populations and ecosystems, determining their distribution, persistence, and productivity. Here we use the synergy of Lagrangian back-trajectories, otolith-derived ages of larvae, and satellite-based chlorophyll-a to identify spawning areas of European anchovy from ichthyoplanktonic data, collected in the Strait of Sicily (Central Mediterranean Sea), i.e., the crucial channel in between the European and African continents. We obtain new evidence of ecosystem connectivity between North Africa and recruitment regions off the southern European coasts. We assess this result by using bio-energetic modeling, which predicts species-specific responses to environmental changes by producing quantitative information on functional traits. Our work gives support to a collaborative and harmonized use of Geographical Sub-Areas, currently identified by the General Fisheries Commission for the Mediterranean. It also confirms the need to incorporate climate and environmental variability effects into future marine resources management plans, strategies, and directives
Campionamento biologico delle catture commerciali Sezione III.C - Variabili biologiche relative al mestiere e dei parametri biologici Sezione III.E - Variabili biologiche relative agli stock del Programma Nazionale Sub-area Geografica (GSA16) – Stretto di Sicilia Anno 2015
Il campionamento biologico delle catture/sbarcati commerciali, sezione C – Relative al mestiere ed E – Relative agli stock, nell’ambito del Programma Nazionale per la Raccolta Dati Alieutici (PNRDA) (Reg. Ce. N°199/2008; N°665/2008 e decisione della commissione N°949/2008), ha l’obiettivo di valutare la composizione in taglia e/o età del pescato ed ottenere altre informazioni sulla biologia delle specie bersaglio, quali le chiavi età /lunghezza, la relazione lunghezza/peso, i parametri di crescita, la composizione in sesso e le condizioni di maturità sessuale.
Il campionamento delle catture/sbarchi commerciali (campionamento biologico - CAMPBIOL) risulta di grande importanza per conoscere come agisce il prelievo dei diversi ”metiers” sulle diverse specie, in termini di variazioni dell’abbondanza e struttura demografica delle risorse da pesca.
Il campionamento biologico risponde, quindi, principalmente alle seguenti esigenze:
1. Ricostruire il pattern di sfruttamento dei diversi ”métiers” per le diverse specie.
2. Ricostruire la struttura demografica delle catture commerciali/sbarchi di ogni specie (in taglia/età ), considerando tutti i ”métiers” che incidono significativamente sull’ammontare globale delle catture.
3. Consentire lo studio dei fenomeni biologici rilevanti, quali la crescita ed il ciclo sessuale, che variano nel corso dell’anno.
4. Acquisire informazioni sulla struttura demografica con specifico riferimento allo stadio di maturazione gonadica (maturitĂ /taglia-etĂ ) ed alla relazione fra lunghezza e peso corporeo (taglia-peso/etĂ ).
Il Programma Nazionale prevede il rilievo dei parametri significativi ai fini della caratterizzazione biologica del prodotto della pesca, principalmente nell’ambito di due differenti moduli:
Modulo di valutazione del settore della pesca
Sezione C – “Variabili biologiche relative al mestiere”
Sezione E – “Variabili biologiche relative agli stock
Campionamento biologico delle catture commerciali Sezione III.C - Variabili biologiche relative al mestiere e dei parametri biologici Sezione III.E - Variabili biologiche relative agli stock del Programma Nazionale
Il campionamento biologico delle catture/sbarcati commerciali, sezione C – Relative al mestiere ed E – Relative agli stock (Campbiol), nell’ambito del Programma Nazionale per la Raccolta Dati Alieutici (PNRDA) (Reg. Ce. N°199/2008; N°665/2008 e decisione della commissione N°949/2008) risulta di grande importanza per conoscere come agisce il prelievo dei diversi ”metiers” sulle diverse specie, in termini di variazioni dell’abbondanza e struttura demografica delle risorse da pesca.
Il campionamento biologico risponde, quindi, principalmente alle seguenti esigenze:
1. Ricostruire la struttura demografica delle catture commerciali/sbarchi di ogni specie (in taglia/età ), considerando tutti i ”métiers” che incidono significativamente sull’ammontare globale delle catture.
2. Ricostruire il pattern di sfruttamento dei diversi ”métiers” per le diverse specie.
3. Consentire lo studio dei fenomeni biologici rilevanti, quali la crescita ed il ciclo sessuale, che variano nel corso dell’anno.
4. Acquisire informazioni sulla struttura demografica con specifico riferimento allo stadio di maturazione gonadica (maturitĂ /taglia-etĂ ) ed alla relazione fra lunghezza e peso corporeo (taglia-peso/etĂ ).
Il Programma Nazionale prevede il rilievo dei parametri significativi ai fini della caratterizzazione biologica del prodotto della pesca, principalmente nell’ambito di due differenti moduli:
Modulo di valutazione del settore della pesca
Sezione C – “Variabili biologiche relative al mestiere”
Sezione E – “Variabili biologiche relative agli stock
Structure of the populations and assessment of the biomass of the coastal demersal resources in the Golfo di Castellammare
Our research, carried out in the continental shelf of the Gulf of Castellammare (N/W
Sicily), aimed at supplying new data regarding the assessment of the abundance and
biomass of the main demersal commercial species, and at depicting the nekton
assemblages structure. Other important aims (sub-tasks) were to detect the effects of the
trawling ban four years after its deployment, to identify areas important from a biological
point of view and to supply general management advice.
The study, involving both trawlable and non-trawlable areas, used trawl surveys for
the first ones, and trammel-gill net (on sandy and rocky bottoms inside the 16-25 m
bathymetric range), beach seine (on sandy bottoms from 0 to about 10 m) and visual
census methods (on rocky, sandy and Posidonia oceanica areas from 0 to 25 m) for the
non-trawlable areas.
Four seasonal trawl surveys, based on a stratified random sampling design, were
carried out from autumn 1993 to summer 1994. Three bathymetric strata were adopted,
each of which was subdivided in elementary sampling units (ESUs). 245 diurnal and
nocturnal hauls of 30 minutes were made. In order to estimate the biomass of the demersal
resources the swept-area method was used. Biomass was expressed as tons in the whole
sampled area (about 57 square nautical miles). The catch per unit effort (CPUE as gr/haul)
of each species caught was calculated. Twelve target species were selected taking into
account both their commercial importance and abundance. For these species, some
reproductive aspects, the length frequencies distribution, the length-weigth relationship,
the growth parameters, the istantaneous total mortality rate were calculated. Moreover,
maps illustrating the distribution of the biomass indices of the target species were drawn.
Monthly diurnal and nocturnal trammel-gill net samplings were carried out for one
year on hard and soft bottom areas. Seasonal maps of the CPUE (gr/500m of net/12h),
based on the diurnal and nocturnal samples obtained in each area were drawn.
Qualitative samples were monthly collected for one year with a beach seine in the
shallow sandy bottoms of the central area of the Gulf.
Two visual census techniques were adopted to obtain furher seasonal data on the fish
assemblages of the non-trawlable areas on different subtrates (i.e., rocky bottoms, sandy
bottoms and artificial reefs). The average values of density and biomass were estimated. Community structure indices were elaborated for each sampling method.
Multivariate analyses were also computed.
The principal results from the trawlable areas can be summarized as follows.
Considering the overall catch, neither significant differences were found among the four
seasons nor between diurnal and nocturnal catches. Anyway, the highest CPUE calculated
as average value per stratum, was obtained in the diurnal winter samples of stratum B
(50983 gr/haul) and the lowest in the nocturnal autumn samples of stratum C (14616
gr/haul). In general diurnal catches were larger than nocturnal. The yields per stratum were
in many cases significantly different between each other. The red mullet (Mullus barbatus)
was nearly always the dominant species in every stratum in the diurnal hauls, as well as in
stratum A (except in winter) in the nocturnal ones. The highest yield for this species was
recorded in the winter samples from the stratum A in the day (18559 gr/haul). The
dominant species in stratum B and C at night was the picarel (Spicara flexuosa), with the
highest values recorded in summer (16440 gr/haul) in stratum B and in autumn (2919
gr/haul) in stratum C. Considering the demersal trawlable fauna as a whole, the outer belt
of stratum A and the whole stratum B were the richest zones inside the study area.
The biomass estimates of the twelve target species showed that the red mullet was by
far the most abundant species (ranging from 34.08 t in summer at night to 170.34 t in
winter in the day), followed by hake (from 5.81 t is summer at night to 62.58 t in winter in
the day), pandora (from 6.93 t in summer at night to 24.94 t in wintwr in the day) and
striped seabream (from 0.47 t in in summer in the day to 10.90 t in autumn at night).
The comparison between the CPUE of experimental trawl surveys carried out before
the trawling ban and our data showed that the commercial demersal resources of the Gulf
underwent a mean seven-fold increase. In particular the red mullet yields increased 33
times (mean value on the whole study area).
A total of 171 taxa were collected in the four surveys. In general the highest values of
specific richness and diversity were recorded in stratum C at night in winter, while the
maximum number of specimens was attained in winter in the diurnal samples of stratum
B. The multivariate analyses separated six areas characterized by different nekton
assemblages, which could be seen as management units.
Nocturnal samples from the trammel-gill net surveys were always significantly
higher than the diurnal ones. The highest yield was recorded on the western rocky bottom,
where an average CPUE of 2895 gr was attained, calculated on an annual basis. The lowest
values were recorded on the soft substrata in the central area (1149 gr), while the artificial
iii
reef area showed intermediate values (2811 gr). On the whole sampled area, cuttlefish
attained 25% of the total catch on an annual basis, followed by the annular seabream
(19.4%). In the western rocky bottoms the most important species were the scorpionfishes,
in the artificial reef the annular seabream and the red mullet and in the soft bottom areas
the wide-eyed flounder and the striped seabream.
Trammel-gill net surveys displayed a significantly higher species richness and
abundance in number of specimens in the nocturnal than in the diurnal samples.
From the visual census surveys damselfish, rainbow wrasse and swallowtail
seaperch were the most abundant species. Sparids (common two-banded seabream, annular
seabream) and serranids (comber and painted comber) were the most frequent and
abundant commercial species observed. The highest biomass (gr/mÂł) was reached in
summer on the artificial reef (52.7), while the lowest was recorded on the sandy bottoms in
autumn (0) and in spring (0.19). The highest density (number of specimens/mÂł) was found
in summer on the artificial reef area (2.85) and the lowest in autumn (0) and spring (0.01)
on the sandy bottoms.
The community structure indices of the rocky and artificial reef areas were
significantly higher than those of the soft bottom areas.
The FCA put into evidence a spatial gradient from the rocky to the sandy bottom fish
assemblages. The artificial reef area was plotted just in the middle of the geometrical
model.
The beach seine surveys highlighted the role of the shallow sandy bottoms as a nursery area for several species. The nekton assemblages of the four sampled sites were
very similar among each other, whereas a strong seasonality was evident by the cluster
analysis results. These data along with those of the trawl surveys showed that the sandy and
muddy bottom areas located between 1 and 40 m are a nursery ground for several
important species: red and striped mullet, pandora, striped seabream and several sparids
and mugilid
Skeptical Look at the Clinical Implication of Metabolic Syndrome in Childhood Obesity
Metabolic syndrome (MetS) is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, which together increase risks of developing future cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). This article is a narrative review of the literature and a summary of the main observations, conclusions, and perspectives raised in the literature and the study projects of the Working Group of Childhood Obesity (WGChO) of the Italian Society of Paediatric Endocrinology and Diabetology (ISPED) on MetS in childhood obesity. Although there is an agreement on the distinctive features of MetS, no international diagnostic criteria in a pediatric population exist. Moreover, to date, the prevalence of MetS in childhood is not certain and thus the true value of diagnosis of MetS in youth as well as its clinical implications, is unclear. The aim of this narrative review is to summarize the pathogenesis and current role of MetS in children and adolescents with particular reference to applicability in clinical practice in childhood obesity
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