Despite some similarities, the silicate igneous component of FRO 93001 (i.e., the pyroxeneplagioclase mineral assemblage) differs in being coarser-grained and containing abundant enstatite. Melting-crystallization modeling suggests that FRO 93001 formed through high-degree partial melting (≥35 wt%; namely, ≥15 wt% silicate melting and ~20 wt% metal melting) of an acapulcoitic source rock, or its chondritic precursor, at temperatures ≥1200 °C, under reducing conditions. The resulting magnesium-rich silicate melt then underwent equilibrium crystallization; prior to complete crystallization at ~1040 °C, it incorporated lodranitic xenoliths.FRO 93001 is the highest-temperature melt from the AL parent-body so far available in laboratory. The fact that FRO 93001 could form by partial melting and crystallization under equilibrium conditions, coupled with the lack of quench-textures and evidence for shock deformation in the xenoliths, suggests that FRO 93001 is a magmatic rock produced by endogenic heating rather than impact melting.
Physiological changes provoked by pain may threaten the integrity of the CNS. In particular, intracranial pressure (ICP) regulates brain perfusion, and its sudden increase may trigger brain haemorrhage. We measured ICP in 51 healthy newborns (gestational age: 35–41 weeks) during blood sampling, by means of a tonometer applied to the anterior fontanelle. Peak ICP values were compared during 3 different types of blood sampling: from the external jugular vein (JV), by heel prick and by heel prick with sensorial saturation. Sensorial saturation consists in giving sensorial stimuli during pain to arrest the transmission of pain to the cerebral cortex. ICP peak values during heel prick were higher than during JV sampling (mean = 26.22 vs. 21.036 mm Hg; p < 0.0001), though babies who underwent the latter procedure had high ICP values before sampling due to the body position required. Heel prick with sensorial saturation was associated with a lower ICP peak (mean = 11.75 mm Hg) than sampling from JV (p < 0.0001). We concluded that heel prick caused a greater rise in ICP than sampling from JV and that sensorial saturation moderated the rise associated with heel prick.
Abstract-In this paper we reconstruct the heterogeneous lithology of an unusual intrusive rock from the acapulcoite-lodranite (AL) parent asteroid on the basis of the petrographic analysis of 5 small (<8.3 g) meteorite specimens from the Frontier Mountain ice field (Antarctica). Although these individual specimens may not be representative of the parent-rock lithology due to their relatively large grain size, by putting together evidence from various thin sections and literature data we conclude that Frontier Mountain (FRO) 90011, FRO 93001, FRO 99030, and FRO 03001 are paired fragments of a medium-to coarse-grained igneous rock which intrudes a lodranite and entrains xenoliths. The igneous matrix is composed of enstatite (Fs 13.3 ± 0.4 Wo 3.1 ± 0.2 ), Cr-rich augite (Fs 6.1 ± 0.7 Wo 42.3 ± 0.9 ), and oligoclase (Ab 80.5 ± 3.3 Or 3.2 ± 0.6 ). The lodranitic xenoliths show a fine-grained (average grain size 488 ± 201 µm) granoblastic texture and consist of olivine Fa 9.5 ± 0.4 and Fe,Ni metal and minor amounts of enstatite Fs 12.7 ± 0.4 Wo 1.8 ± 0.1 , troilite, chromite, schreibersite, and Ca-phosphates. Crystals of the igneous matrix and lodranitic xenoliths are devoid of shock features down to the scanning electron microscope scale. From a petrogenetic point of view, the lack of shock evidence in the lodranitic xenoliths of all the studied samples favors the magmatic rather than the impact melting origin of this rock. FRO 95029 is an acapulcoite and represents a separate fall from the AL parent asteroid, i.e., it is not a different clast entrained by the FRO 90011, FRO 93001, FRO 99030, and FRO 03001 melt, as in genomict breccias common in the meteoritic record. The specimen-to-meteorite ratio for the AL meteorites so far found at Frontier Mountain is thus 2.5.
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