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Luminous Blue Variables are massive evolved stars, here we introduce this outstanding class of objects. Described are the specific characteristics, the evolutionary state and what they are connected to other phases and types of massive stars. Our current knowledge of LBVs is limited by the fact that in comparison to other stellar classes and phases only a few “true” LBVs are known. This results from the lack of a unique, fast and always reliable identification scheme for LBVs. It literally takes time to get a true classification of a LBV. In addition the short duration of the LBV phase makes it even harder to catch and identify a star as LBV. We summarize here what is known so far, give an overview of the LBV population and the list of LBV host galaxies. LBV are clearly an important and still not fully understood phase in the live of (very) massive stars, especially due to the large and time variable mass loss during the LBV phase. We like to emphasize again the problem how to clearly identify LBV and that there are more than just one type of LBVs: The giant eruption LBVs or η Car analogs and the S Dor cycle LBVs.

Kaposi's varicelliform eruption (eczema herpeticum) is the name given to a distinct cutaneous eruption caused by herpes simplex and certain other viruses that infect persons with preexisting dermatosis. Most commonly it is associated with atopic dermatitis. We report a case of a three-year-old atopic child who presented with extensive vesicular eruption suggestive of Kaposi's varicelliform eruption. There was history of fever, malaise and extensive vesicular eruptions. Diagnosis was made based on clinical features and Tzanck smear examination. Patient responded adequately to oral acyclovir therapy.

Osteoclasts are multinucleated giant cells that resorb bone, ensuring development and continuous remodelling of the skeleton and the bone marrow haematopoietic niche. Defective osteoclast activity leads to osteopetrosis and bone marrow failure 1 – 9 , whereas excess activity can contribute to bone loss and osteoporosis 10 . Osteopetrosis can be partially treated by bone marrow transplantation in humans and mice 11 – 18 , consistent with a haematopoietic origin of osteoclasts 13 , 16 , 19 and studies that suggest that they develop by fusion of monocytic precursors derived from haematopoietic stem cells in the presence of CSF1 and RANK ligand 1 , 20 . However, the developmental origin and lifespan of osteoclasts, and the mechanisms that ensure maintenance of osteoclast function throughout life in vivo remain largely unexplored. Here we report that osteoclasts that colonize fetal ossification centres originate from embryonic erythro-myeloid progenitors 21 , 22 . These erythro-myeloid progenitor-derived osteoclasts are required for normal bone development and tooth eruption. Yet, timely transfusion of haematopoietic-stem-cell-derived monocytic cells in newborn mice is sufficient to rescue bone development in early-onset autosomal recessive osteopetrosis. We also found that the postnatal maintenance of osteoclasts, bone mass and the bone marrow cavity involve iterative fusion of circulating blood monocytic cells with long-lived osteoclast syncytia. As a consequence, parabiosis or transfusion of monocytic cells results in long-term gene transfer in osteoclasts in the absence of haematopoietic-stem-cell chimerism, and can rescue an adult-onset osteopetrotic phenotype caused by cathepsin K deficiency 23 , 24 . In sum, our results identify the developmental origin of osteoclasts and a mechanism that controls their maintenance in bones after birth. These data suggest strategies to rescue osteoclast deficiency in osteopetrosis and to modulate osteoclast activity in vivo. Multinucleated osteoclasts required for normal bone development and tooth eruption in the mouse originate from embryonic erythro-myeloid progenitors and are maintained after birth by fusion with circulating monocytes.

The Jiaojia giant gold deposit is the largest gold deposit in China, with a total gold reserve of approximately 1200 t. Until now, the knowledge of the exhumation history of post-mineralization period is limited, in particular for the low-temperature thermochronology studies of samples below −1000 m. In this work, we combined zircon fission-track (ZFT) and apatite fission-track (AFT) dating of samples between −1100 and −2000 m to determine the post-mineralization cooling and exhumation history of the Jiaojia giant gold deposit. The ZFT ages ranged from 144.2±6.3 to 124.4±5.5 Ma, representing the cooling period and the disturbance of ore-forming fluid. The AFT ages ranged from 28.1±2.6 to 16.2±1.0 Ma, recording the exhumation and cooling processes. With reference to previous low-temperature thermochronology studies in the Jiaojia goldfield, we estimated the exhumation rate and amount of the Jiaojia giant gold deposit and reconstructed its exhumation and preservation history. The exhumation history was divided into four stages, rapid exhumation (~120–95 Ma), relatively slow exhumation (~95–50 Ma), slow exhumation (~50–30 Ma) and relatively rapid exhumation (since 30 Ma). Each stage corresponds to geological events related to the basin-mountain coupling that have occurred since the Cretaceous in the Jiaodong area, namely, a strong tectonic extension and volcanic eruption in the Jiaolai Basin, subsidence of the Jiaolai Basin and Wangshi Group molasse sedimentary, tectonic quiescence, and the Linqu Group basalt eruption of the Jiaobei uplift. Our results show that the exhumation of the Jiaojia giant gold deposit is ~5.2±1.2 km and the orebody erosion degree is relatively low, indicating huge prospecting potential deep in the Jiaojia giant gold deposit. These findings have significance and practical value for deep prospecting in the Jiaodong area.

Earlier, whole-rock data assisted in constraining magmatic processes accountable for the evolution of Giant Plagioclase Basalt (GPB), although plagioclase chemistry data-based implications are rare and critical, while combining with bulk-rock chemistry to understand magmatic processes regionally. For this reason, giant and small-size plagioclase grains were analyzed using Electron Probe Microanalysis (EPMA). Core to margin of the Kalsubai Subgroup GPB grains show significant variation ranging from An 99 Ab 1 –An 94 Ab 6 to An 65 Ab 35 –An 5 Ab 95 , respectively. Nucleation of An-rich core initiated in the mid-lithospheric level at elevated temperatures, varying between 1490 and 1510°C, but successive An-poor intermediate and marginal layers crystallized at low temperatures between 1200–1360°C and 910–930°C that also in shallower depth, respectively. Moreover, supercharged feldspar-rich magma persisted throughout the Kalsubai Subgroup lavas, as noticed by the absence of zoned plagioclase. Almost similar processes were followed, but in a subdued manner at 1220–1300°C temperature in the Kevlari–Kalan area that lies ~900 km apart in the eastern Deccan Volcanic Province (DVP). Presence of plume-fed magma chamber is also justified by the size and thickness of the Kalsubai Subgroup lavas. Uninterrupted recharge of magma source was continued as Ab/An value remains constant throughout the Kalsubai Subgroup lava sequence. Further, residence period of 3.2–17.4 ka is assigned to GPB of the Kalsubai Subgroup. Owing to high eruption rate, younger formations of the main DVP do not contain GPB, but Kevlari Kalan GPB contains labradorite (An 60 Ab 40 –An 50 Ab 50 ) rich plagioclase, crystallized during storage of the magma for a shorter interval comparing to Kalsubai Subgroup GPB lavas. Research Highlights Giant plagioclase contains Ca- rich (An 99 ) core and Ca-poor (An 65 ) rim Three crystallization episodes assigned to Kalsubai GPB and one to Kevlari Kalan GPB Owing to high eruption rate, younger western DVP is devoid of GPB.

Large‐scale, catastrophic mass wasting is a major process contributing to the dismantling of oceanic intraplate volcanoes. Recent studies, however, have highlighted a possible feedback relationship between flank collapse, or incipient instability, and subsequent episodes of structural rearrangement and/or renewed volcano growth. The Teno massif, located in northwestern Tenerife (Canary Islands), is a deeply eroded Miocene shield volcano that was built in four major eruptive phases punctuated by two lateral collapses, each removing >20–25 km3 of the volcano's north flank. In this paper, we use detailed field observations and petrological and geochemical data to evaluate possible links between large‐scale landslides and subsequent volcanism/magmatism during Teno's evolution. Inspection of key stratigraphic sequences reveals that steep angular unconformities, relics of paleolandslide scars, are marked by polymict breccias. Near their base, these deposits typically include abundant juvenile pyroclastic material, otherwise scarce in the region. While some of Teno's most evolved, low‐density magmas were produced just before flank collapses, early postlandslide lava sequences are characterized by anomalously high proportions of dense ankaramite flows, extremely rich in clinopyroxene and olivine crystals. A detailed sampling profile shows transitions from low‐Mg # lavas relatively rich in SiO2 to lavas with low silica content and comparatively high Mg # after both landslides. Long‐term variations in Zr/Nb, normative nepheline, and La/Lu are coupled but do not show a systematic correlation with stratigraphic boundaries. We propose that whereas loading of the growing precollapse volcano promoted magma stagnation and differentiation, the successive giant landslides modified the shallow volcano‐tectonic stress field at Teno, resulting in widespread pyroclastic eruptions and shallow magma reservoir drainage. This rapid unloading of several tens of km3 of near‐surface rocks appears to have upset magma differentiation processes, while facilitating the remobilization and tapping of denser ankaramite magmas that were stored in the uppermost mantle. Degrees of mantle melting coincidently reached a maximum in the short time interval between the two landslides and declined shortly after, probably reflecting intrinsic plume processes rather than a collapse‐induced influence on mantle melting. Our study of Teno volcano bears implications for other oceanic volcanoes where short‐term compositional variations may also directly relate to major flank collapse events.

Catastrophic volcanic eruptions, large earthquakes beneath big cities, or giant earthquakes at subduction zones are apparently the biggest problems facing the sustainability of human society. However, imminent prediction methods for these events have never been established, except that volcanic eruptions can only be predicted by exceptional efforts by dedicated researchers. Even if a prediction method has been established, the method cannot significantly reduce infrastructure damage, although it could slightly reduce the number of fatalities. On the other hand, prevention of eruptions or earthquakes could significantly reduce, not only the number of fatalities, but also infrastructure damage. Therefore, the authors propose (1) gradual energy release by supercritical power generation to prevent catastrophic eruptions; (2) gradual seismic energy release by injecting water into seismic sources to prevent large earthquakes beneath big cities; and (3) exploding existing nuclear warheads underground to prevent giant earthquakes at subduction zones. Necessary technical developments, costs, risks, and problems will also be explained.

Kaposi's varicelliform eruption (eczema herpeticum) is the name given to a distinct cutaneous eruption caused by herpes simplex and certain other viruses that infect persons with preexisting dermatosis. Most commonly it is associated with atopic dermatitis. We report a case of a three-year-old atopic child who presented with extensive vesicular eruption suggestive of Kaposi's varicelliform eruption. There was history of fever, malaise and extensive vesicular eruptions. Diagnosis was made based on clinical features and Tzanck smear examination. Patient responded adequately to oral acyclovir therapy.

Deccan Trap magmas may have erupted through multiple centers, the most prominent of which may have been a shield volcano-like structure in the Western Ghats area. The lavas are predominantly tholeiitic; alkalic mafic lavas and carbonatites are rare. Radioisotope dating, magnetic chronology, and age constraints from paleontology indicate that although the eruption started some 68 Ma, the bulk of lavas erupted at around 65-66 Ma. Paleomagnetic constraints indicate an uncertainty of ± 500,000 years for peak volcanic activity at 65 m.y. in the type section of the Western Ghats. Maximum magma residence times were calculated in this study based on growth rates of \"giant plagioclase\" crystals in lavas that marked the end phase of volcanic activity of different magma chambers. These calculations suggest that the > 1.7 km thick Western Ghats section might have erupted within a much shorter time interval of 55,000 years, implying phenomenal eruption rates that are orders of magnitude larger than any present-day eruption rate from any tectonic environment. Other significant observations/conclusions are as follows: (1) Deccan lavas can be grouped into stratigraphic subdivisions based on their geochemistry; (2) While some formations are relatively uncontaminated others are strongly contaminated by the continental crust; (3) Deccan magmas were produced by 15-30% melting of a Fe-rich lherzolitic source at 3-2 GPa; (4) Parent magmas of the relatively uncontaminated Ambenali formation had a primitive composition with 16%MgO, 47%SiO^sub 2^; (5) Deccan magmas were generated much deeper and by significantly more melting than other continental flood basalt provinces; (6) The erupted Deccan tholeiitic lavas underwent fractionation and magma mixing at 0.2 GPa. The composition and origin of the crust and crust/mantle boundary beneath the Deccan are discussed with respect to the influence of Deccan magmatic episode.[PUBLICATION ABSTRACT]

Field studies on the eruption environment and prevailing cooling conditions of multi-tiered lava flows of the type exemplified by the Giant's Causeway were carried out at localities on the Columbia River Plateau, southern Iceland, on the islands of Mull and Staffa and around the Giant's Causeway, NE Ireland. Common features can be recognized in the volcanology of such flows in all the localities examined. These include palaeotopographic evidence of river valleys giving conditions conducive to the ponding of flows and the damming of existing drainage; evidence of high rainfall regimes or abundant surface water; association of interlava lacustrine and fluviatile sediments; association of hyaloclastite flow foot breccias within multi-tiered basalt lava successions and evidence of large volume lava flows and high eruption rates. Examination of the petrography of the upper curvi-columnar parts of the lava (the entablature) shows textural signs of quenching, compared with the lower more regular columnar zone (the colonnade). These common field and petrographic features confirm the model of multi-tiered flow formation by modification of the cooling regime in the upper part of the flow following inundation of the hot lava surface by displaced river drainage.