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We use high‐resolution three‐dimensional X‐ray microtomography to investigate fluid displacement during steady‐state three‐phase flow in a cm‐sized water‐wet sandstone rock sample. The pressure differential across the sample is measured which enables the determination of relative permeability; capillary pressure is also estimated from the interfacial curvature. Though the measured relative permeabilities are consistent, to within experimental uncertainty, with values obtained without imaging on larger samples, we discover a unique flow dynamics. The most non‐wetting phase (gas) is disconnected across the system: gas flows by periodically opening critical flow pathways in intermediate‐sized pores. While this phenomenon has been observed in two‐phase flow, here it is significant at low flow rates, where capillary forces dominate at the pore‐scale. Gas movement proceeds in a series of double and multiple displacement events. Implications for the design of three‐phase flow processes and current empirical models are discussed: the traditional conceptualization of three‐phase dynamics based on analogies to two‐phase flow vastly over‐estimates the connectivity and flow potential of the gas phase. Key Points: Gas flow is disconnected at steady‐state conditions, explaining the low gas relative permeability seen in this water‐wet three‐phase systemIntermittent gas‐oil flow is observed in intermediate‐sized pores despite flowing at low flowrates, where capillary forces are dominantThe traditional use of two‐phase data to predict three‐phase flow vastly over‐estimates the connectivity and mobility of the gas phase [ABSTRACT FROM AUTHOR]

Objectives: To determine the effect of maternal antenatal administration of vitamin K1 on activity level of vitamin K-dependent coagulation factors and on the occurrence of periventricular-intraventricular hemorrhage (PIVH). Methods: This study was conducted on 90 infants who were classified into; Group A: 30 preterm whose mothers received antenatal vitamin K1, Group B: 30 preterm whose mothers did not receive antenatal vitamin K1, and Group C: 30 healthy full term newborns as a control group. All newborns were subjected to measurement of the activity level of vitamin K-dependent coagulation factors (FII, FVII, FIX and FX). Cranial ultrasound was done on the 1st, 3rd and 7th days of life. Results: Group B showed significantly lower activity level of FII and FX with higher incidence of PIVH compared with group A. Neonates who developed PIVH by the 7th day in both group A and B had significantly lower activity level of vitamin K-dependent coagulation factors. Conclusion: when antenatal vitamin K1 was given to pregnant women at imminent risk of preterm labor, their preterm neonates were able to achieve a clotting status approaching that of full term neonates and are less liable to develop PIVH. [ABSTRACT FROM AUTHOR]