301 research outputs found
On the complementarity between on-the-job training and R&D: a brief overview
No full textIn this paper I briefly review the existing literature on the complementarity between on-the-job training and R&D. I show that the complementarity is studied, on the one hand, within two lines of economic research, labour economics and endogenous growth. On the other hand, from the empirical point of view, some recent papers seem to confirm results of theoretical studies, by arguing that a specific training for R&D is quite often a crucial condition for adopting new technologies. I conclude that this issue is treated by different subsets of economic literature which need other improvements, and particularly, an integration
Origin and evolution of the Italian subterranean termite Reticulitermes lucifugus (Isoptera: Rhinotermitidae).
No full textThe Holarctic genus Reticulitermes shows seven species within the Mediterranean Basin. While phylogeny and systematics at continental level has been deeply investigated, a few studies concentrated on local ranges. To gain a clearer picture of the diversity and evolution of the Italian species Reticulitermes lucifugus, we analyzed the mitochondrial cytochrome oxidase II (COII) gene marker in newly collected colonies across the Peninsula. Data were gathered with all R. lucifugus sequences available from previous studies; COII sequences of the closely related Iberian taxa were also added to the data set. Maximum-likelihood, median-joining and statistical parsimony network elaborations on the resulting 119 colonies all agreed in indicating that: (i) the Sardo-Corsican subspecies R. lucifugus corsicus, strictly related to Southern Italian populations (including the Sicilian ones), is phylogenetically closer to the Iberian Reticulitermes grassei; and (ii) R. lucifugus lucifugus peninsular populations are structured into three clusters. The phylogenetic relationships and the biogeography of extant taxa suggest a scenario in which R. lucifugus ancestors colonized the Italian region through the Sardo-Corsican microplate during its Oligocene-Miocene anticlockwise rotation. Moreover, well after the colonization took place, northward range expansion might have produced the presently observed genetic diversity, as inferred from haplotype and nucleotide diversity estimates. On the whole, this study highlights the evolution of Italian Reticulitermes taxa and supports the importance of a wide taxon sampling especially when dealing with organisms easily dispersed by human activities
Preparation, Characterisation and Testing of Photocatalytic Polymeric Membranes with Entrapped or Suspended TiO2
No full textVarious cellulose triacetate (CTA) or polysulfone (PSf) membranes with entrapped polycrystalline TiO2 were prepared by using different methods of the so-called phase inversion process. Porosity and permeability of the membranes increased by increasing the amount of entrapped TiO2 while rejection decreased. The photoactivity of entrapped TiO2 for the degradation of congo-red was compared with that of the same quantity of suspended TiO2 and the results indicated that TiO2 was always more efficient when used in suspension. A hybrid configuration consisting of a continuous membrane photoreactor with the photocatalyst in suspension showed to be the most promising one
The use of Holocene geological and archaeological markers to determine coseismic deformation: new observations from the Taormina coastal area (northeastern Sicily).
No full textRaised Holocene paleo-shorelines along the Capo Schiso coast, Taormina: New evidence of recent co-seismic deformation in northeastern Sicily (Italy)
No full textDetailed mapping of geomorphological, biological and archaeological sea-level markers around the Capo Schiso volcanic headland, a few kilometers south of Taormina, north-eastern Sicily, has documented the occurrence of three Holocene paleo-shorelines raised at different altitudes. The uppermost shoreline (PS1) is represented by a fossiliferous beach deposit that is heavily eroded and only few small sections, at elevations ranging between similar to 3 and similar to 5 m above the present sea-level, are visible. The middle shoreline (PS2) was found at a maximum altitude of similar to 3 m and is represented by algal rims, remnants of barnacle bands and vermetid concretions, and by a fossiliferous beach deposit. The lowermost shoreline (PS3) includes remnants of algal rims, vermetid concretions, fossil barnacle bands and a beachrock, and reaches an elevation of 1.60-1.80 m. New radiocarbon dating results, integrated with published ages from nearby paleo-shoreline outcrops, constrains for the Taormina region an average uplift rate of 1.7-1.8 mm/yr in the last 5 ka, and the occurrence of three co-seismic uplift events at 4.4-3.9 ka, 2.1-1.8 ka and <= 1.0 ka ago. Abrupt displacements are tentatively attributed to footwall uplift along an offshore normal fault, but further investigations are needed to better constrain the causative source of past earthquakes. Notwith-standing, based on coastal tectonic analysis, this paper provides a new assessment of age and recurrence time of Holocene earthquakes in a historically strong seismogenic area. (C) 2011 Elsevier Ltd. All rights reserved
Raised Holocene paleo-shorelines along the Capo Schisò coast, Taormina: New evidence of recent co-seismic deformation in northeastern Sicily (Italy)
No full textDetailed mapping of geomorphological, biological and archaeological sea-level markers around the Capo Schisò volcanic headland, a few kilometers south of Taormina, north-eastern Sicily, has documented the occurrence of three Holocene paleo-shorelines raised at different altitudes. The uppermost shoreline (PS1) is represented by a fossiliferous beach deposit that is heavily eroded and only few small sections, at elevations ranging between ~3 and ~5. m above the present sea-level, are visible. The middle shoreline (PS2) was found at a maximum altitude of ~3. m and is represented by algal rims, remnants of barnacle bands and vermetid concretions, and by a fossiliferous beach deposit. The lowermost shoreline (PS3) includes remnants of algal rims, vermetid concretions, fossil barnacle bands and a beachrock, and reaches an elevation of 1.60-1.80. m. New radiocarbon dating results, integrated with published ages from nearby paleo-shoreline outcrops, constrains for the Taormina region an average uplift rate of 1.7-1.8. mm/yr in the last 5. ka, and the occurrence of three co-seismic uplift events at 4.4-3.9. ka, 2.1-1.8. ka and ≤1.0. ka ago. Abrupt displacements are tentatively attributed to footwall uplift along an offshore normal fault, but further investigations are needed to better constrain the causative source of past earthquakes. Notwithstanding, based on coastal tectonic analysis, this paper provides a new assessment of age and recurrence time of Holocene earthquakes in a historically strong seismogenic area. © 2011 Elsevier Ltd
MILLSTONES COASTAL QUARRIES AS INDICATOR OF RELATIVE SEA LEVEL CHANGES
No full textThe Italian coasts shows numerous archaeological remains which reveals the activities that were
carried out along the coast for thousands of years of history. In order to use archaeological
structures for coastal studies, an accurate estimate of their relationship to the sea level at the time of
construction is required (Lambeck et al 2004, Antonioli et al 2007, Auriemma & Solinas 2009).
Millstone coastal quarries are only documented in southern Italy; they are carved on beachrock,
calcarenites and other sedimentary rock easy to be exploited. Few archaeological information have
been published about quarries for millstones extraction; they are documented since around 2500 yr
BP (Amouretti, 1986; Amouretti, Brun, 1993; Brun, 1997).
Millstone quarries carved within sandstone bedrocks and nowadays partially submerged was used
as archaeological sea level marker for two sites in Calabria and Sicily by Scicchitano et al.(2011).
In this study we analyzed 11 coastal sites of: Sicily (Capo d’Orlando, Letojanni, Giardini Naxos),
Calabria (Soverato, Tropea, Capo dell’Armi, Crotone, Roccella Ionica), Campania (Palinuro,
Scario) and Apulia (Polignano San Vito).
Thanks to the discovery and dating of an iron wedge used as tool for carving, for the first time we
can restrict the period of exploitation of this specific type of quarry (Ronchitelli, 1993). In addition,
based on geological knowledge of each sector and on measures made on the quarries, we present
considerations on functionality, geological uplift rate and reconstruction of possible ages of each
studied archaeological sites
Reproductive strategies and breeding systems in Reticulitermes subterranean termites (Isoptera, Rhinotermitidae)
No full textTermites are eusocial insects that live in colonies characterized by cooperative behavior, where most individuals forego their own reproduction and help to raise the offspring of a few nest members. This may impact on the colony abilities to adapt and exploit the environment. In subterranean termites of the genus Reticulitermes, a new colony is settled by a single, heterosexual pair of winged individuals (primary reproductives; kings and queens); as colony maturate and/or upon founders death, neotenics (secondary reproductive; SRs) develop and contribute to offspring production. This leads to inbreeding as SRs are genetically related. In some species, including the Italian R. lucifugus, primary queens produce secondary queens by parthenogenesis (P); then, secondary queens will mate with the primary king extending the genetic contribution of the primary queen through time (Asexual Queen Succession, AQS), eventually helping to avoid inbreeding. As a consequence of the increasing genetic contribution of the primary queen, AQS colonies show a female-biased sex ratio of winged reproducers. Here we present population genetics and sex ratio analyses of R. lucifugus, and compare results with data on two other species: R. flavipes and R. grassei. Genetic data indicated the presence of AQS in R. lucifugus and its absence in the other two species, accordingly to winged sex ratio observations. Data confirmed that P occurs through a mechanism of terminal fusion. Moreover, winged reproductives resulted all produced by amphigony, confirming that P is only used for secondary queen production. Finally, morphometric and biomass analyses performed on R. lucifugus winged reproductives suggested a larger investment in female sex in AQS colonies. The AQS system has been observed to be scattered among termites, occurring through different mechanisms and leading to different outcomes. This variability still need to be explained in the light of social behavior evolution
Illness behaviour and somatization in general practice
No full textCopyright © 1996 Published by Elsevier Science Inc.In the primary care setting, the early recognition that a patient has psychological problems is frequently hindered by the deceptive mode of presentation known as somatization. In a cross-sectional survey of patients attending suburban General Practitioners in a large metropolitan city, the General Health Questionnaire-30 (GHQ-30) and the Illness Behavior Questionnaire (IBQ) were completed by 201 patients. A comparison was made between somatizing and nonsomatizing patients with new inceptions of illness in terms of the risk of the presence of a mild nonpsychotic psychiatric illness and aspects of illness behavior. For the group as a whole, somatizing patients were more likely to be older and female. Male somatizers differed from male nonsomatizers by showing greater disease conviction and affective disturbance and more readiness to acknowledge difficulties in their lives other than health problems. No differences were found between female somatizing and nonsomatizing patients. We conclude that, while male patients who somatize psychological distress may be distinguished from male nonsomatizers early in their illness, in terms of their illness behavior, these differences are not seen as early distinguishing characteristics in female patients who present to their General Practitioners with physical problems for which no organic cause can be establishedJ. Scicchitano, P. Lovell, R. Pearce, J. Marley and I. Pilowsk
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