Me4+-bearing (Me4+ = Sn, Ti) dravite analogs were synthesized in the system MeO2-MgO-Al2O3-B2O3-SiO2-NaO-H2O at 700 °C and 4 / 0.2 GPa in four hydrothermal experiments. Tourmalines form rosette-like ...aggregates and needle-like crystals that are chemically homogeneous. Tourmaline crystals obtained in high-pressure runs (4 GPa) are much smaller (up to 0.1 × 2 µm) and have lower Me4+ (0.27 wt. % SnO2, 0.57 wt. % TiO2) than those from the low-pressure (0.2 GPa) runs (up to 1 × 5 µm; 1.77 wt. % SnO2, 2.25 wt. % TiO2). Synthetic analogs of rutile, quartz and coesite were obtained in the system TiO2-MgO-Al2O3-B2O3-SiO2-NaO-H2O, whereas synthetic analogs of cassiterite, tin-rich (up to ~ 19.55 wt. % SnO2) Na-pyroxene, MgSn(BO3)2 (Mg-analogue of tusionite), quartz and coesite were synthesized in the system SnO2-MgO-Al2O3-B2O3-SiO2-NaO-H2O. We suggest that at a high temperature (≥ 700 °C), the pressure negatively affects the Ti incorporation into the tourmaline structure. In contrast, at relatively low pressures, the Ti incorporation in tourmaline structures is governed by the Ti content in the mineral-forming medium. Low-pressure conditions are feasible for Sn incorporation in the tourmaline structure. The presence of Ti4+ and Sn4+ cations in structures of the synthesized tourmalines (probably at octahedrally coordinated sites), is also indicated by changes in the unit-cell parameters.
► Low temperature thermochronology from HP and UHP rocks of the Kaghan Valley, Pakistan. ► Oligocene to Middle Miocene ages for the northern part of the Valley. ► Late Miocene to Pliocene ages for ...the southernmost Kaghan Valley. ► Discussion about an extended early Plateau in the north, comparable to Deosai. ► Discussion about Miocene activity of the MBT in the south, and enhanced erosion.
Apatite fission track and apatite and zircon (U–Th)/He ages were obtained from high- and ultra high-pressure rocks from the Kaghan Valley, Pakistan. Four samples from the high altitude northern parts of the valley yielded apatite fission track ages between 24.5±3.7 and 15.6±2.1Ma and apatite (U–Th)/He ages between 21.0±0.6 and 5.3±0.2Ma. These data record cooling of the formerly deeply-subducted high-grade metamorphic rocks induced by denudation and exhumation consistent with extension and back sliding along the reactivated, normal-acting Main Mantle Thrust. Overlap at around 10Ma between fission track and (U–Th)/He ages is recognised at one location (Besal) showing that fast cooling occurred due to brittle reactivation of a former thrust fault. Widespread Miocene cooling is also evident in adjacent areas to the west (Deosai Plateau, Tso Morari), most likely related to uplift and unroofing linked to continued underplating of the Indian lower crust beneath Ladakh and Kohistan in the Late Eocene to Oligocene. In the southernmost part of the study area, near Naran, two significantly younger Late Miocene to Pliocene apatite fission track ages of 7.6±2.1 to 4.0±0.5Ma suggest a spatial and temporal separation of exhumation processes. These younger ages are best explained by enhanced Late Miocene uplift and erosion driven by thrusting along the Main Boundary Thrust.
Unterschiede im schulischen Bildungserfolg zwischen Kindern unterschiedlicher sozialer und kultureller Herkunft manifestieren sich meist schon im Kindergartenalter. Deswegen sind eine frühe ...Prävention von Beeinträchtigungen und gleichzeitig eine frühe Förderung angeraten. In den letzten Jahren wurden überall in Deutschland Angebote der Familienbildung geschaffen, von denen viele sich besonders an sozial benachteiligte Familien richten. Jedoch gibt es Hinweise, dass solche Angebote eher von bildungsnahen, sozial besser gestellten Familien genutzt werden. Gründe dafür liegen zum einen in den Familien, zum anderen auch in der Art der Angebote und ihrer Strategie, potenzielle Teilnehmende anzusprechen. Am Beispiel des Projekts Chancenreich soll im vorliegenden Beitrag auf Besonderheiten verschiedener Familienbildungsangebote, speziell im Hinblick auf die Zugangsproblematik, eingegangen werden. Dafür werden zunächst die Auswirkungen solcher Programme skizziert und die Herausstellungsmerkmale von Chancenreich diskutiert. Die soziodemographischen Ergebnisse der Erhebung von teilnehmenden und nicht-teilnehmenden Familien (N=1252) zeigen, dass das Projekt Chancenreich zwar eher Familien mit besserem Bildungsabschluss und geringerer Kinderanzahl anspricht, gleichwohl nehmen aber auch Familien am Programm teil, die teilweise mehrfachen Benachteiligungsrisiken ausgesetzt sind, weil die Eltern z. B. keinen oder einen geringen Bildungsabschluss besitzen, alleinerziehend oder erwerbslos sind. Dieses Ergebnis wird im Hinblick auf die Fragestellung, ob es dem Projekt Chancenreich gelingt, sozial benachteiligte Familien zu erreichen, diskutiert. (DIPF/Orig.).
Differences in educational success between children of different social and cultural backgrounds manifest themselves as early as preschool age. Therefore, the need for early intervention programs has been discussed. In recent years, Germany has established various early intervention programs, many of which are specifically targeted at socially disadvantaged families. However, evidence exists that many of these programs recruit primarily participants with higher educational and social backgrounds. Reasons for this lie in the families themselves but also in the type of programs offered and their strategies of recruitment. The following paper focuses on the question who participates in early intervention programs, using the project Chancenreich Herford as an example. After outlining the impacts of such programs, the special features of Chancenreich are highlighted with particular interest in its design and recruitment strategy. Results from socio-demographic analyses using a census of all participating and non-participating families in Herford (N = 1252) show that Chancenreich achieves the goal to reach families with multiple deprivation risks (e.g. parents with low levels of formal education, single-parent families, or unemployed parents). Yet, a significant number of participating families does have higher educational degrees and fewer children. (DIPF/Orig.).
Meteorite impact processes are ubiquitous on the surfaces of rocky and icy bodies in the Solar System, including the Moon. One of the most common accessory minerals, zircon, when shocked, produces ...specific micro-structures that may become indicative of the age and shock conditions of these impact processes. To better understand the shock mechanisms in zircon from Apollo 15 and 16 impact breccias, we applied transmission electron microscopy (TEM) and studied nano-structures in eight lunar zircons displaying four different morphologies from breccias 15455, 67915, and 67955. Our observations revealed a range of shock-related features in zircon: (1) planar and non-planar fractures, (2) “columnar” zircon rims around baddeleyite cores, (3) granular textured zircon, in most cases with sub-µm-size inclusions of monoclinic ZrO
2
(baddeleyite) and cubic ZrO
2
(zirconia), (4) silica-rich glass and metal inclusions of FeS and FeNi present at triple junctions in granular zircon and in baddeleyite, (5) inclusions of rutile in shocked baddeleyite, (6) amorphous domains, (7) recrystallized domains. In many grain aggregates, shock-related micro-structures overprint each other, indicating either different stages of a single impact process or multiple impact events. During shock, some zircons were transformed to diaplectic glass (6), and others (7) were completely decomposed into SiO
2
and Zr-oxide, evident from the observed round shapes of cubic zirconia and silica-rich glass filling triple junctions of zircon granules. Despite the highly variable effect on textures and Zr phases, shock-related features show no correlation with relatively homogeneous U–Pb or
207
Pb/
206
Pb ages of zircons. Either the shock events occurred very soon after the solidification or recrystallization of the different Zr phases, or the shock events were too brief to result in noticeable Pb loss during shock metamorphism.
Variations in the form of the human face, which plays a role in our individual identities and societal interactions, have fascinated scientists and artists alike. Here, we review our current ...understanding of the genetics underlying variation in craniofacial morphology and disease-associated dysmorphology, synthesizing decades of progress on Mendelian syndromes in addition to more recent results from genome-wide association studies of human facial shape and disease risk. We also discuss the various approaches used to phenotype and quantify facial shape, which are of particular importance due to the complex, multipartite nature of the craniofacial form. We close by discussing how experimental studies have contributed and will further contribute to our understanding of human genetic variation and then proposing future directions and applications for the field.
A network of monazite-rich, coarse-grained veins and fine-grained veins permeating the mid-Proterozoic Concordia Granite in the Kliphoog area near Springbok, Namaqualand, North Cape Province, South ...Africa, are described with respect to their whole-rock chemistry, petrography, mineralogy, and mineral chemistry along with zircon and monazite geochronology. Chondrite-normalized trace element data indicate that the coarse-grained veins are enriched in LREE relative to the Concordia Granite with HREE enrichment being somewhat variable. HREE in altered Concordia Granite, at the contact with the coarse-grained vein, are heavily depleted compared to unaltered Concordia Granite while the LREE show the same approximate abundances. Chloritization is common in the coarse-grained veins along mineral grain boundaries with chlorite replacing most of the orthopyroxene megacrysts, though occasional remnants of orthopyroxene remain in the core. A traverse across one of the coarse-grained veins showed no obvious mineral chemical trends between the vein and surrounding granite. Relic Fe-rich megacryst orthopyroxene has an Al2O3 content of around 2.0 wt% suggesting formation at around 700 °C. The Fe-rich biotite has mean Ti values ranging from TiO2 = 4.1 to 1.2 wt% indicating formation at 700–800 °C. The coarse-grained veins and fine-grained veins are characterized by abundant accessory Th-rich monazite, heterogeneously distributed in the veins. Lesser amounts of monazite are found in the granite. Other accessory minerals in the veins and granite include zircon and rare fluorapatite. Back-scattered electron imaging shows that the anhedral to euhedral monazite grains (up to more than 1500 μm in size) tend to be complexly zoned with light and dark areas. Lighter areas are more enriched in Th and/or Ce than darker areas. This complex zoning can occur as magmatic/sector zoning and more commonly as a complex series of metasomatic alteration events. Metasomatic textures, which are due to variable fluid-induced mobility of Th, U, and REE, are the result of a coupled dissolution-reprecipitation process and have been reproduced experimentally using high pH alkali-bearing fluids. The analysis of seven zircon cores from the Concordia Granite yields a concordia age of 1173 ± 15 Ma suggesting that an age of ca. 1170 Ma most likely represents the true emplacement age of the Concordia Granite. The mean 207Pb/206Pb age of 1042 ± 9 Ma obtained on zircon from the main coarse-grained vein is interpreted as the crystallization age of the vein. 207Pb/235U monazite ages are highly variable in the veins and Concordia Granite host, ranging from ca. 1050 to 1000 Ma. This supports the petrographic and mineral chemistry evidence that the monazite U--Pb system was variably affected by a continuous or multi-pulse metasomatic/metamorphic event(s) occurring between 1050 and 1000 Ma. U--Pb analyses of deformed monazite crystals from a radioactive sinistral shear zone of the Kliphoog area yield a mean 207Pb/235U age of ca. 1006 ± 9 Ma, indicating that the late circulation of Th-LREE-rich fluids synchronous with strike-slip deformation occurred at ca. 1000 Ma. On a regional scale, the intrusion of the Kliphoog coarse-grained vein is contemporaneous with granulite-facies metamorphism as well as the A-type granitoid magmatism of the Spektakel Suite, mafic magmatism of the Koperberg Suite, and emplacement of the monazite vein-type deposit at Steenkampskraal. Therefore, a genetic relationship between the formation of monazite-rich Kliphoog veins and these metamorphic, magmatic, and metallogenic events is proposed.
•REE- and actinide-rich charnockite veins Kliphoog, Namaqualand, South Africa.•Vein formation results from intrusion of REE- and actinide-rich melts and fluids.•Alteration of zircon and monazite in the granitoid veins record/time metasomatic events.
Tourmaline rare-earth element (lanthanides + Y) patterns could provide valuable geological information as tourmalines are the most abundant borosilicates on Earth and are stable at extreme PT ...conditions. The lanthanide-bearing tourmalines were synthesized for the first time in a series of high- (4 GPa) and low-pressure (0.2 GPa) hydrothermal experiments. We have found that Ln-content (Ln = La3+, Nd3+, Eu3+ and Yb3+) in synthetic tourmalines varies significantly (1.13–8.35 wt% Ln2O3) with Yb < La ≤ Nd < Eu independent of pressure conditions. Ln-content in synthetic tourmalines, obtained at low pressure is 2–3 times higher, than those from high-pressure experiments. The Nd- and Eu-rich synthetic tourmalines exhibit cathodo- photoluminescence properties (blue and violet luminescence colors for Nd and Eu, respectively), which confirms trivalent state of Ln in tourmaline structure. Single-crystal X-ray diffraction data for synthetic tourmalines (Nd-rich a 15.893(1), c 7.130(1) Å; Eu-rich a 15.903(5), c 7.168(3) Å) show that Eu3+ and Nd3+ occupy the 9-coordinated X-site in the tourmaline structure. The general formula of obtained synthetic tourmalines can be expressed as Ln3+1-x (Mg,Al)3 (Al,Mg)6 (Si6O18) (BO3)3 (OH,O)3 (OH,O) (0.05 ≤ x ≤ 0.97). The crystal-chemical features and lanthanide speciation in synthesized tourmalines are herein discussed and compared to natural and synthetic compounds.
The present study examines the effects of a family support program on children's socio-emotional and language development. We analyze how participating in courses that aim to improve the relationship ...between parents and their children is associated with child development. Two different course formats (parenting skills-focused and parent-child interaction-focused courses) are investigated. The study has a cross-sectional design and uses a sample of 185 parents and their children in the intervention group and 58 parents and their children in the non-intervention group. Findings suggest that participation in parent-child interaction-focused courses significantly predicts the vocabulary skills (Peabody Picture Vocabulary Test) of the children. Regarding the socio-emotional skills of the children, we find that childcare professionals' rating of problem behavior (Strengths and Difficulties Questionnaire (SDQ)) was significantly lower for the children in the intervention group. Additionally, parents` rating of children's prosocial skills (SDQ) were significantly lower for children whose parents attended parenting skills-focused-courses. Implications and future research on the effectiveness of family support programs are discussed.
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