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Larger symbiont-bearing foraminifera are prominent and important producers of calcium carbonate in modern tropical environments. With an estimated production of at least 130 million tons of CaCO(3) per year, they contribute almost 5% of the annual present-day carbonate production in the world's reef and shelf areas (0-200 m) and approximately 2.5% of the CaCO(3) of all oceans. Together with non-symbiont-bearing smaller foraminifera, all benthic foraminifera are estimated to annually produce 200 million tons of calcium carbonate worldwide. The majority of foraminiferal calcite in modern oceans is produced by planktic foraminifera. With an estimated annual production of at least 1.2 billion tons, planktic foraminifera contribute more than 21% of the annual global ocean carbonate production. Total CaCO(3) of benthic and planktic foraminifera together amounts to 1.4 billion tons of calcium carbonate per year. This accounts to almost 25% of the present-day carbonate production of the oceans, and highlights the importance of foraminifera within the CaCO(3) budget of the world's oceans.

1. Myoblasts from expanded primary cultures were implanted into cryodamaged soleus muscles of adult BALB/c mice. One to four months later isometric tension recordings were performed in vitro, and the male donor cells implanted into female hosts were traced on histological sections using a Y-chromosome-specific probe. The muscles were either mildly or severely cryodamaged, which led to reductions in tetanic muscle force to 33 % (n = 9 muscles, 9 animals) and 70% (n = 11) of normal, respectively. Reduced forces resulted from deficits in regeneration of muscle tissue as judged from the reduced desmin-positive cross-sectional areas (34 and 66 % of control, respectively). 2. Implantation of 106 myogenic cells into severely cryodamaged muscles more than doubled muscle tetanic force (to 70% of normal, n = 14), as well as specific force (to 66% of normal).Absolute and relative amounts of desmin-positive muscle cross-sectional areas were significantly increased indicating improved microarchitecture and less fibrosis. Newly formed muscle tissue was fully innervated since the tetanic forces resulting from direct and indirect (nerve-evoked) stimulation were equal. Endplates were found on numerous Y-positive muscle fibres. 3. As judged from their position under basal laminae of muscle fibres and the expression of M-cadherin, donor-derived cells contributed to the pool of satellite cells on small-and largediameter muscle fibres. 4. Myoblast implantation after mild cryodamage and in undamaged muscles had little or no functional or structural effects; in both preparations only a few Y-positive muscle nuclei were detected. It is concluded that myoblasts from expanded primary cultures -unlike permanent cell lines -significantly contribute to muscle regeneration only when previous muscle damage is extensive and loss of host satellite cells is severe.

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Larger symbiont-bearing foraminifers of the genus Amphistegina are currently expanding their biogeographic range in the Mediterranean Sea. They are rapidly progressing northwestward, closely approaching the Adriatic and the Tyrrhenian seas. The shift in range locally leads to profound ecological changes where amphisteginids have become the dominant species along entire stretches of coastline. Mass deposits of amphisteginids reflect an increased carbonate production and reduced assemblage diversity, and these are likely to trigger major changes in ecosystem functioning. It is anticipated that the ongoing warming trend will convey the northwestward migration of amphisteginid foraminifers. To project future species distributions we applied a speciesdistribution model (SDM) that is based on ecological niche constraints of current distribution ranges. Our model indicates that further warming is likely to cause a northwestward range extension and predicts dispersal through the straits of Sicily, Messina, and Otranto into the Tyrrhenian and Adriatic seas. Our results corroborate reports that show a remarkable increase and range expansion of tropical species, indicating a continued meridionalization of the Mediterranean Sea.

In the summers of 1993 and 1994 a series of meteorological rockets and sounding rockets were launched from the Andøya Rocket Range (69°N) during the SCALE and ECHO campaigns in order to investigate the state of the mesosphere and lower thermosphere (SCALE = “SCAttering Layer Experiment”; ECHO indicates that radar and lidar echoes are investigated). At the same location a Rayleigh lidar was operational during these campaigns and searched for enhanced backscatter signals from the upper mesosphere indicative of the presence of noctilucent clouds (NLC). In five cases the lidar detected a NLC and the atmospheric temperature profile was obtained simultaneously by in situ techniques. A literature survey shows that there are only three more cases of unambiguous and simultaneous observations of NLC temperature and altitude. The temperature profiles obtained during SCALE and ECHO are as expected for the high‐latitude summer season: The mean mesopause temperature is 135 K at an altitude of 87.5 km. The variability of the temperatures is smaller above ∼84 km altitude than below. The mean temperature below the mesopause shows a remarkable repeatability ever since the first measurements 30 years ago; at the lower edge of the NLC heights (82 km) it is again and again observed to be in the range 150 ± 2 K and the variability within each data set is only a few Kelvins. Such an “equithermal submesopause” in summer puts a serious constraint on any model prediction of secular changes of temperatures in the upper mesosphere. The mean altitude of the NLCs as determined from our lidar measurements is 83.1 km which is surprisingly close to the very first height determinations more than 100 years ago. It is conceivable that this repeatability in altitude reflects a similar repeatability of the thermal structure. There is no apparent correlation between the conditions at the mesopause and the occurrence of NLCs at lower altitudes. The physical reason behind this is presumably related to the fact that the wind direction changes at ∼87 km height, which implies that the air masses observed above the rocket site near mesopause altitudes have been advected from different locations than those at NLC heights. The NLCs are always located below the mesopause, and the temperature in the NLC layer is observed to be lower than 154 K. Our results are compatible with the idea that NLCs consist of ice particles which start to nucleate around the mesopause, sediment to lower altitudes while growing, become observable by the lidar and/or by the naked eye, and finally evaporate once they approach the higher temperatures around 82 km.

The re-examination of marine alien species or Non-indigenous species (NIS) reported in Italian Seas by December 2018, is here provided, particularly focusing on establishment success, year of first record, origin, potential invasiveness, and likely pathways. Furthermore, their distribution is assessed according to marine subregions outlined by the European Union (EU) Marine Strategy Framework Directive: Adriatic Sea (ADRIA), Ionian Sea and Central Mediterranean Sea (CMED), and Western Mediterranean Sea (WMED). In Italy, 265 NIS have been detected with the highest number of species being recorded in the CMED (154 species) and the WMED (151 species), followed by the ADRIA (143). Most of these species were recorded in more than one subregion. The NIS that have established stable populations in Italian Seas are 180 (68%), among which 26 have exhibited invasive traits.Among taxa involved, Macrophyta rank first with 65 taxa. Fifty-five of them are established in at least one subregion, mostly in the ADRIA and the CMED. Crustacea rank second with 48 taxa, followed by Polychaeta with 43 taxa, Mollusca with 29 taxa, and Pisces with 28 taxa, which were mainly reported from the CMED. In the period 2012-2017, 44 new alien species were recorded, resulting in approximately one new entry every two months. Approximately half of the NIS (~52%) recorded in Italy have most likely arrived through the transport-stowaway pathway related to shipping traffic (~28% as biofoulers, ~22% in ballast waters, and ~2% as hitchhikers). The second most common pathway is the unaided movement with currents (~19%), followed by the transport-contaminant on farmed shellfishes pathway  (~18%). Unaided is the most common pathway for alien Fisshes, especially in CMED. Escapes from confinement account for ~3% and release in nature for ~2% of the NIS. The present NIS distribution hotspots for new introductions were defined on the first recipient area/location in Italy. In ADRIA the hotspot is Venice which accounts for the highest number of alien taxa introduced in Italy, with 50 newly recorded taxa. In the CMED, hotspots of introduction are the Taranto and Catania Gulfs, hosting 21 first records each. The Strait of Sicily represents a crossroad between the alien taxa from the Atlantic Ocean and the Indo-Pacific area. In the WMED, hotspots of bioinvasions include the Gulfs of Naples, Genoa and Livorno.This review can serve as an updated baseline for future coordination and harmonization of monitoring initiatives under international, EU and regional policies, for the compilation of new data from established monitoring programs, and for rapid assessment surveys.

We present the results of first simultaneous and common volume observations of noctilucent clouds (NLC) and polar mesosphere summer echoes (PMSE) by two ground‐based lidars and one VHF radar. The measurements were performed at the ALOMAR facility (69°N, 16°E) during the time period July 23 through August 18, 1994. Throughout this period, NLC layers were observed by the lidars on four occasions. During each of these four lidar‐observed NLC events, PMSE layers were also observed overhead by the radar. These joint NLC/PMSE events divide into two distinct types: (1) tightly coupled and (2) loosely coupled NLC and PMSE layers. In one of the events, the PMSE layer developed into a well‐defined double layer with only 0.8‐km vertical separation, while the lidar‐observed NLC layer matched closely in time and space the lower PMSE sublayer. Within all four NLC/PMSE layers, the wind speed increased sharply with increasing altitude with wind shears amounting to 0.03 s−1 and larger. Current theories can explain some of the observed layer features.