Results 31 to 40 of about 1,405,729 (293)
Applied SciencesOne of the most common problems in drilling operations is lost circulation, which can significantly increase well costs and lead to issues such as pipe sticking, blowouts, and even well closures.
Reda Abdel Azim +2 more
doaj +1 more source
Tikrit Journal of Pure Science, 2023 Lost circulation, the loss of drilling fluid into holes or fractures throughout the geological formations being drilled, is the most expensive problem encountered in drilling operations for oil and gas wells.
Mayssa N. Shehab +2 more
doaj +1 more source
Lost Circulation Technology Development Status [PDF]
, 1992 Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well.
Scott, Douglas D. +11 more
core
Microbiome‐blood–brain barrier interactions in aging — mechanisms and therapeutic potential
FEBS Letters, EarlyView.Aging reshapes the gut microbiome (↓SCFA‐producing commensals; ↑pro‐inflammatory outputs), shifting circulating metabolites (↓SCFAs; ↑LPS, ↑TMAO, ↑PAA) that act at the BBB to increase nonspecific transcytosis, alter transport, and promote astrocyte reactivity, heightening brain vulnerability.
Daniel Cuervo‐Zanatta +3 more
wiley +1 more source
Tumour–host interactions in Drosophila: mechanisms in the tumour micro‐ and macroenvironment
Molecular Oncology, EarlyView.This review examines how tumour–host crosstalk takes place at multiple levels of biological organisation, from local cell competition and immune crosstalk to organism‐wide metabolic and physiological collapse. Here, we integrate findings from Drosophila melanogaster studies that reveal conserved mechanisms through which tumours hijack host systems to ...
José Teles‐Reis, Tor Erik Rusten
wiley +1 more source
Applied SciencesTo address the challenges associated with severe lost-circulation formations, including large loss-channel dimensions, rapid fluid losses, and the tendency of conventional bridging or physical-filling materials to accumulate at fracture entrances rather ...
Hongjun Wu +6 more
doaj +1 more source
Lost circulation technology development projects [PDF]
, 1990 Lost circulation is the phenomenon where circulating drilling fluid is lost to fractures or pores in the rock formation rather than returning to the surface through the wellbore annulus.
Glovka, D.A.
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Modeling Lost Circulation Through Drilling-Induced Fractures
, 2017 SummaryPrevious lost-circulation models assume either a stationary fracture or a constant-pressure- or constant-flowrate-driven fracture, but they cannot capture fluid loss into a growing, induced-fracture driven by dynamic circulation pressure during ...
Yongcun Feng, K. E. Gray
core +1 more source
Analysis of lost circulation on the Norwegian Continental Shelf [PDF]
, 2021 Lost circulation (downhole losses of drilling fluid) is defined by the absence or reduction of drilling fluid pumped through the drill string while drilling the wells, which filtrates the formation instead of flowing up to the surface.
Schaathun Grelland, Sander
core
Hijacking emergency granulopoiesis: Neutrophil ontogeny and reprogramming in cancer
Molecular Oncology, EarlyView.Neutrophils are highly plastic innate immune cells; their functions in cancer extend beyond the tumour microenvironment. This Review summarises current understanding of neutrophil maturation and heterogeneity and highlights tumour‐induced granulopoiesis as a systemic programme that expands immature, immunosuppressive neutrophils via tumour‐derived ...
Gabriela Marinescu, Yi Feng
wiley +1 more source