Hypothermia in Preterm Newborns: Impact on Survival.

Background. Globally, prematurity is the leading cause of neonatal mortality, and hypothermia is one of its contributing factors. The goal of this study was to determine the association between hypothermia and mortality. Methods. A prospective, multi-center, descriptive clinical study was conducted in 5 hospitals in Ethiopia. Axillary temperatures were taken at the time of admission to the newborn intensive care units (NICU) and followed during the NICU stay. Results. A total of 3852 premature neonates (<37 weeks) were admitted to the NICUs from July 2016 to May 2018. Of these infants, 1109 (28.8%) died and 2991 (79.6%) had hypothermia. Hypothermia was associated with perinatal asphyxia (89.5%), RDS (86.2%), and resuscitation at birth (82.7%). Admission temperatures in preterm newborns were inversely associated with mortality and morbidity. Conclusion. Hypothermia at admission is associated with neonatal mortality in premature neonates in Ethiopia. RDS and perinatal asphyxia were the main factors associated with hypothermia. The very high prevalence and association with mortality warrants quality improvement interventions.

Melting during late-stage rifting in Afar is hot and deep.

Investigations of a variety of continental rifts and margins worldwide have revealed that a considerable volume of melt can intrude into the crust during continental breakup, modifying its composition and thermal structure. However, it is unclear whether the cause of voluminous melt production at volcanic rifts is primarily increased mantle temperature or plate thinning. Also disputed is the extent to which plate stretching or thinning is uniform or varies with depth with the entire continental lithospheric mantle potentially being removed before plate rupture. Here we show that the extensive magmatism during rifting along the southern Red Sea rift in Afar, a unique region of sub-aerial transition from continental to oceanic rifting, is driven by deep melting of hotter-than-normal asthenosphere. Petrogenetic modelling shows that melts are predominantly generated at depths greater than 80 kilometres, implying the existence of a thick upper thermo-mechanical boundary layer in a rift system approaching the point of plate rupture. Numerical modelling of rift development shows that when breakup occurs at the slow extension rates observed in Afar, the survival of a thick plate is an inevitable consequence of conductive cooling of the lithosphere, even when the underlying asthenosphere is hot. Sustained magmatic activity during rifting in Afar thus requires persistently high mantle temperatures, which would allow melting at high pressure beneath the thick plate. If extensive plate thinning does occur during breakup it must do so abruptly at a late stage, immediately before the formation of the new ocean basin.