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Microstratigraphy And Taphonomy Of Rudist Shell Concentrations In Upper Cretaceous Limestones, Cilento Area (Southern Italy)
No full textRudist bed type and distribution has been investigated in Upper Cretaceous limestones cropping out in the northern Cilento area (southern Italy). These limestones are dominated by fine-grained, peloidal, silty packstone in which rudist rich beds intercaled. An inner shelf environment may be inferred on the basis of the recognized sedimentary and taphonomic features.
The rudist shell beds are characterized by low species diversity, with slight differences in abundance of a few species belonging to the Durania, Bournonia, Sauvagesia, Gorjanovicia and Biradiolites genera, that usually form oligo- or monospecific congregations.
The internal fabric of these levels (i.e. orientation, arrangement, packing and sorting of the skeletal elements; internal microstatigraphy) has permitted to distinguish two broad shell bed categories: a) shell beds considered as “Primary Shell Concentration” in which the shell concentration is essentially created by the behaviour of local shell producers, preserved in situ and in growth position; b) shell beds considered as “Hydraulic Shell Concentration”, that were deposited under the influence of hydraulic processes and/or input of surrounding bioclastic sediments. The taphonomic analyses allowed us to highlight the role of some of the biotic and abiotic factors which controlled the distribution of the rudists in the various habitats.
The increase of physical disturbance (expecially hydrodynamism) is the primary difference between these shell bed categories. The establishment and development of the densest rudist congregations appear to be related to the accomodation space made available my means of relative sea level rise. The lowering of the sea-level was often accompanied by the increased influence of waves and/or currents on the sea bed and the consequent sediment disturbance and demise of the rudist lithosome, although other factors cannot be excluded
Rudist lithosomes related to current pathways in Upper Cretaceous, temperate-type, inner shelves: a case study from the Cilento area, southern Italy
No full textShallow-water foramol limestones have been studied from a locality in the southern Apennines in which outcrop conditions show an excellent overview of the lateral and vertical evolution of rudist bodies and allow their geometry and the dynamic aspects to be reconstructed.
The lithofacies suggest open depositional settings characterized by peloidal silty-muddy sediments. Rudists inhabited well-defined sectors of these shelves, giving rise to wide biostromal bodies, and supplied most of the skeletal debris via bioerosion and minor physical breakdown. In particular, the characteristics of rudist lithosomes document the existence of a complex network of channel-like depressions. In such a depositional context, the evolution of rudist lithosomes seems to have been strongly controlled by the hydrodynamic conditions of the environment. The resulting composite rudist assemblages are characterized by individuals quite often found toppled and oriented parallel to bedding, suggesting continuous sediment movement and/or removal between the organisms. The good preservation of the shells and the common articulation of the valves, however, point to an absence of sustained transport but rather a slight sediment destabilization. The gross lenticular geometry of the shell beds could be related to the above-mentioned patterns of weak, maybe channelized, currents and/or pathways. In most cases, lithosomes may be considered as a multistorey growth in channel-like systems in a persistently subtidal setting.
The depositional setting may be considered as a low-energy system with low tidal range, such that facies transition is very gradual and facies belts are broad, while distinct shoal/barrier deposits are absent. Such a depositional system implies a very low bathymetric slope on which wave energy was minimal, dampened by friction along a broad expanse of shallow water hundreds of kilometres wide. The resulting sea bottoms, dominated by biogenic carbonate sedimentation, were separated by troughs and/or tidal passes.
In such a depositional context, rudist colonization on channel margins assumes particular importance as it documents the rudist ability to exploit a wide array of environments, comparable to that of oysters in Recent seas, and reflecting the probable opportunistic nature of rudists
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Analyzing the 20-year declining trend of hospital length-of-stay in European countries with different healthcare systems and reimbursement models
Full text linkThe study aims to investigate the last 20-year (2000–2019) of hospital length of stay (LOS) trends and their association with different healthcare systems (HS) among 25 European countries. A panel dataset was created using secondary data from Eurostat and Global Burden of Disease study databases, with dependent and control variables aggregated at the national level over a period of 20 years. A time trend analysis was conducted using a weighted least squares model for panel data to investigate the association between LOS, HS models [National Health Service (NHS), National Health Insurance, Social Health Insurance (SHI), and Etatist Social Health Insurance], healthcare reimbursement schemes [Prospective Global Budget (PGB), Diagnosis Related Groups (DRG), and Procedure Service Payment (PSP)], and control variables. The study showed a reduction of average LOS from 9.20 days in 2000 to 7.24 in 2019. SHI was associated with a lower LOS compared to NHS (b = − 0.6327, p < 0.05). Both DRG (b = 1.2399, p < 0.05) and PSP (b = 1.1677, p < 0.05) reimbursement models were positively associated with LOS compared to PGB. Our results confirmed the downward trend of LOS in the last 20 years, its multifactorial nature, and the influence of the SHI model of HS. This could be due to the financial incentives present in fee-for-service payment models and the role of competition in creating a market for healthcare services. These results offer insight into the factors influencing healthcare utilization and can inform the design of more effective, efficient, and sustainable HS. © The Author(s) 2024
Leadership condivisa, consolidamento delle alleanze e prestazione di gruppo nelle reti tra imprese: uno studio time-lagged.
No full textIl contributo indaga la relazione tra leadership condivisa e percezione della prestazione di gruppo in 13 gruppi di governo di aggregazioni di impresa, nonché il ruolo moderatore del consolidamento della rete e dell'aspettativa di proseguire la collaborazione inter-organizzativa. L'indagine si è svolta in due tempi: la leadership condivisa misurata a T1 e la percezione della prestazione di gruppo a T2, 18 mesi dopo. I risultati mostrano che la leadership condivisa predice negativamente la percezione della prestazione di gruppo, soprattutto nei gruppi/alleanze di nuova costituzione e in quelli che non hanno intenzione di proseguire la collaborazione, mentre ha un effetto positivo su quelli che hanno già collaborato in passato e in quelli che intendono proseguire la loro collaborazione.This paper investigates the relationship between shared leadership and perception of team performance in 13 inter-organizational governing teams. It also investigates whether stability of the alliance and expectation of continuing the collaboration moderate the relationship. The survey took place in two waves: shared leadership was measured at T1 and perception of team performance at T2, 18 months later. Results show that shared leadership negatively predicts perception of team performance, especially in newly established teams/alliances and in those that do not intend to continue the collaboration, while it has a positive effect on teams that already collaborated in the past and that intend to continue their collaboration
Upper Cretaceous rudist lithosomes in a channellized shelf setting. Cilento area, southern Italy
No full textVaraiety of coralline algal deposits (rhodalgal facies) from the Bays of Naples and Pozzuoli (northern Tyrrenian Sea, Italy).
No full textThe Bays of Naples and Pozzuoli are extremely influenced by their geological and tectonic history, which has had a strong influence on the features and morphology of the sea bottom. The occurrence and variability of the coralline algal (rhodalgal) facies both in active factories and in palimpsest and/or winnowed deposits in the Bay of Naples and the Bay of Pozzuoli is reported in this paper. The present-day coralline algal deposits resulted from the complex volcano-tectonic events and biological changes which occurred in the Phlegrean Fields, in particular after the sea-level lowstand at the last glacial maximum regression and the succeeding Holocene transgression
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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