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Early Cretaceous planktonic foraminiferal assemblages include rare planispiral and pseudoplanispiral morphotypes with elongate chambers that BouDagher-Fadel et al. assigned to Schackoina or accommodated in the new genus Claviblowiella. New findings of well-preserved planktonic foraminiferal faunas from the Lesches en Diois (SE France) section, the Cismon core (NE Italy), the Calabianca (NW Sicily) section and the Upper Aptian of Deep Sea Drilling Project (DSDP) Site 545 drilled off Morocco, have allowed a better understanding of the morphological features of these rare, unevenly distributed taxa. Our data demonstrate that each small planispiral species with globular chambers has a corresponding “clavate” morphotype which (as the “normal” forms) exhibits a smooth, finely perforate wall. Consequently, the latter have been assigned here to the genus Globigerinelloides and treated as subspecies of the “non-clavate” taxa. The (clavate) subspecies belonging to the genus Globigerinelloides here retained are G. duboisi sigali Longoria, G. maridalensis elongatus subsp. nov., G. blowi lobatus subsp. nov. and G. paragottisi clavatus subsp. nov., while Globigerinelloides minai Obregon de la Parra is not retained. In addition, a new genus, Pseudoschackoina, type species Planomalina saundersi Bolli (senior synonym of Hastigerinoides cepedai Obregon de la Parra, has been formalised for individuals possessing elongate, pointed, laterally compressed chambers, bearing tubulospines arranged on a pseudoplanispiral (dysaxial) coiling mode. Stratigraphically, in the sections studied the first taxon to appear is Pseudoschackoina saundersi, in the uppermost part of the Selli Level (=OAE1a), immediately followed, just above the OAE1a, by all the “clavate” globigerinelloidids. Regarding the last occurrences, Pseudoschackoina saundersi and G. maridalensis elongatus disappear in the lower part of the Globigerinelloides algerianus Zone, Globigerinelloides paragottisi clavatus at the top of the same zone, while Globigerinelloides blowi lobatus and G. duboisi sigali range up to the lower part of the Ticinella bejaouaensis Zone.

Rock fragments from mud breccia extruded by mud volcanoes, discovered during the TTR-4 cruise of the R/V Gelendzhik on the western Mediterranean Ridge, are represented by a number of different lithologies. They provide important information on the composition, genesis, and age of the deep-seated sedimentary series of the basin. Lithological description and age determination of the main rock types obtained as clasts from mud breccia were made on the basis of a study of ninety-seven samples. Depositional processes and environments of their accumulation were determined using sedimentological criteria. The sedimentary section through which mud volcanoes erupted on the western Mediterranean Ridge includes Aptian–Albian claystones, Late Cretaceous limestones, Paleogene siliciclastic rocks, and a variety of Miocene limestones and mudstones. The rock clasts studied throw insight into the evolution of the western sector of the Eastern Mediterranean Basin from, at least, Aptian time. The Aptian–Albian clayey series have been deposited in the marine conditions of a relatively narrow basin with a high input of terrigenous clayey material. During the Late Cretaceous the basin enlarged, terrigenous input into deep parts of the basin decreased, and carbonate pelagic sedimentation became prevalent. Regression in Paleogene time led to the deposition of thick terrigenous siliciclastic series of deltaic–prodeltaic sediments. Extensive turbidite systems were emplaced in the western sector of the Eastern Mediterranean during the Miocene, along with predominantly carbonate pelagic sedimentation.

Il Foglio 096-Seregno della Carta Geologica d'Italia a scala 1: 50. 000 è stato realizzato nell'ambito del Progetto CARG (legge n. 226/99), per mezzo di una Convenzione tra il Servizio Geologico d'Italia e la Regione Lombardia e tra questa e il CNR "Istituto per la dinamica dei processi ambientali". Esso è localizzato in Lombardia nord-occidentale al margine meridionale delle Prealpi tra i due rami del Lario e comprende gran parte dell'Anfiteatro del Lario, edificato dal ghiacciaio dell'Adda durante le glaciazioni

A multidisciplinary study of the upper Albian—Cenomanian portion of the Cismon section (Venetian region, northern Italy) was undertaken in order to characterize the cyclic alternations of carbonate-rich and carbonate-poor layers and to investigate their possible origin and cyclic patterns. Limestone semicouplets are characterized by abundant radiolarians and micarbs (micron-sized calcitic fragments), common planktonic foraminifera, strong bioturbation, good oxygenation as expressed by the Mn* and V/(V+Ni) parameters, high Si/Al ratio, low K/Al, in the absence of pyrite and organic matter. The marlstone semicouplets are, on the contrary, frequently laminated, rich in pyrite and organic matter with common fish remains in the absence of radiolarians. The Mn* and V/(V+Ni) parameters indicate that the marlstone deposition occurred in dysoxic to anoxic conditions, which allowed the preservation of organic matter. The low Si/Al ratio and high K/Al ratio, the latter related to abundant feldspars, indicate that marlstones received a substantial contribution from a terrigenous source. The abundance of biogenic silica suggests that during limestone deposition surface waters were rather fertile due to an efficient recycling of nutrients from deeper waters. The enhanced fertility was coupled with an efficient current system at the welloxygenated sea floor which prevented the organic matter from accumulating. During marlstone deposition, surface waters were less fertile than in the limestone semicouplets, but still within the mesotrophic spectrum as indicated by the presence of fertility index species among calcareous nannofossils, whereas the bottom waters were oxygen-depleted. To accommodate fertility at the surface with stagnation at the bottom the scenario implies an enhanced stratification caused by an increase in freshwater runoff monitored by 18O-depleted δ values. In the meantime, the water discharge supplied the nutrients to the surface waters necessary for the calcareous nannofossils to proliferate. The cyclic organization of limestone/marlstone couplets as revealed by power spectral analysis seems to represent climatic cycles. The alternating conditions are (1) efficient mixing, highly fertile surface and near-surface waters, and a well-oxygenated seafloor to (2) enhanced water runoff or decreased evaporation, or both, and oxygen-depleted bottom waters. We suggest that this deterministic sedimentary cyclicity could be explained by periodic orbital-climatic cycles, in tune with the Milankovitch cycles. Within this scenario, the latest Cenomanian Bonarelli Level is an exceptional event marked by a large positive δ13C spike. It is characterized by high to very high fertility conditions in surface waters caused by increased upwelling that engendered high nutrient levels in near-surface waters. The enhanced production of organic matter was in excess for the oxygen available at the bottom floor, thus allowing the organic matter to accumulate in the sediments.

We have made oxygen and carbon isotope measurements on limestone samples of Albian to Eocene age recovered from the Bottaccione Gorge section in the Umbrian Apennines, central Italy. Additional measurements have been made on topmost Maastrichtian and Palaeocene sediments from the adjacent Contessa Highway section. Our data from the Bottaccione Gorge show 13C maxima at the Cenomanian/Turonian boundary and during the Palaeocene, as well as a pronounced 13C minimum 7 metres above the clay layer at the K/T boundary. Our data from the Contessa Highway show a 13C minimum 9 metres above the K/T boundary clay. These minima are probably diagenetic artifacts. In the Bottaccione Gorge there is evidence for a hiatus in the early Middle Eocene. The Palaeocene of the Bottaccione Gorge appears to have been affected by slumping or faulting (in addition to the diagenetic overprinting) giving a spurious δ13C recovery after the K/T boundary, the Contessa Highway section appears to be more complete. The Coniacian-Maastrictian is characterized by relatively stable 13C values. Our data indicate an increase in δ18O (and therefore possible cooling) across the Cretaceous/Tertiary boundary in both the Bottaccione and Contessa Highway sections.

A multidisciplinary study was carried out on core C106 collected in the Salerno Gulf (southern Tyrrhenian Sea). Two tephra layers recovered in the core, N18O record of Globigerinoides ruber and Globigerina bulloides and seven 14C calibrated ages provided the stratigraphic framework. The core sediments cover the last 28 kyr BP. Seismostratigraphic analysis of a high resolution acoustic profile, integrated by the dated core samples, allowed us to reconstruct the architecture and age of sedimentary bodies on the continental shelf. An integrated study based on different taxonomic groups (nannofossils, pteropods, foraminifera, and palynomorphs) provided palaeoclimatic trends, in agreement with changes in the isotopic composition of oxygen. The upper part of the Last Glacial period, the deglaciation phase and the Holocene were identified. Correlation between marine and continental records of palaeoenvironmental changes confirms a similar reconstruction of the last deglaciation as in the central and southern Mediterranean Sea. The Late Pleistocene^Holocene boundary was recognised at about 11.7 kyr BP. Between about 9.5 and 6 kyr BPand at 3.3 kyr BP some warmer episodes were recorded. The measured lower isotopic values, together with some features of the fossil assemblages recorded from 9.5 to 6 kyr BP, may be related to the oceanographic setting that led to the deposition of Sapropel S1 in the Mediterranean basin. ; 2002 Elsevier Science B.V. All rights reserved.

Introduction The combined use of Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG) enables a direct investigation of cortical-evoked responses in humans. The physiology of the peaks characterizing the TMS-evoked EEG responses has not been clearly elucidated yet. EEG is able to detect fast-inhibitory post synaptic potentials (fIPSPs, Objectives In the present study we characterized the pharmaco-physiology of TEPs in healthy volunteers by using two GABA-A receptors positive modulators: alprazolam and zolpidem. The main aim of the study was to test to which extent early TEPs are affected by fast inhibitory neurotransmission through the GABA-A receptor. Materials and methods Twenty healthy subjects participated in a pseudorandomized, placebo-controlled, double-blind crossover design, using a single oral dose of alprazolam (1 mg), a classical benzodiazepine preferentially binding on alpha1, alpha2, alpha3 and alpha5 subunit bearing subtypes of the GABA-A receptor, and zolpidem (10 mg), which mainly binds at the alpha1 subtype. TEPs were recorded by TMS-EEG before and 90 min after drug administration and the effects of the drugs on the TEP amplitudes were statistically evaluated. Results A non parametric cluster-based permutation analysis of amplitudes at channel-level was run for placebo, alprazolam and zolpidem administration. Both alprazolam and zolpidem, increased the amplitude of the negative potential at 45 ms after stimulation (N45). Moreover, a strong positive correlation was found between their modulation on the N45 magnitude. In addition, alprazolam but not zolpidem decreased the amplitudes of the later TEPs, in particular, the negative at 100 ms (N100) and the positive at 180 ms (P180). Conclusion We provide first-time evidence that the N45 potential may reflect a biological marker of alpha1 containing GABA-A receptor activity. The broader modulation of several TEP components by alprazolam could be explained by its wider pharmacological profile, as it is responsible for the activation of several subtypes of GABA-A receptors.