Direct observations of the surface and shape of model nanocolloidal gels associated with measurements of the spatial distribution of water content during drying show that air starts to significantly penetrate the sample when the material stops shrinking. We show that whether the material fractures or not during desiccation, as air penetrates the porous body, the water saturation decreases but r...

Alterations of structure and function of the microcirculation in hypertension in the elderly and changes with normotensive aging have not been fully clarified. We studied capillary pressure, density, and skin microvascular function in 46 subjects in 3 groups: elderly subjects (aged >60 years) with untreated hypertension (n=16), elderly normotensive subjects (n=16), and young normotensive subjec...

An infinite elastic medium with a planar crack is considered. The crack is subjected to the pressure of fluid injected at a point on the crack surface. Description of the crack growth is based on the lubrication equation (balance of the injected fluid and the crack volume), the equation for crack opening caused by fluid pressure on the crack surface, the Poiseuille equation related local fluid ...

Recent studies in humans have suggested sex differences in venous compliance of the lower limb, with lower compliance in women. Capillary fluid filtration could, however, be a confounder in the evaluation of venous compliance. The venous capacitance and capillary filtration response in the calves of 12 women (23.2 +/- 0.5 years) and 16 men (22.9 +/- 0.5 years) were studied during 8 min lower bo...

The coronary capillary flow is analyzed theoretically based on continuum mechanics. The capillary is a long, elastic, and permeable vessel loaded externally by tissue pressure, and it is subject to possible periodic length changes, together with adjacent myocytes. Capillary flow is driven by arteriolar-venular pressure difference. Ultrafiltration due to transmural hydrostatic and osmotic gradie...

• The contribution of the pulmonary venous system to the pulmonary vascular resistance has been a subject of increasing interest." The pulmonary veins are sometimes considered to consist of wide inactive vessels; however, histological studies have revealed a layer of smooth muscle in these veins, especially at their junction with the left atrium. The veins may also respond histologieally by ven...

SEE PAGE 9 W hen pulmonary hypertension (PH), defined by mean pulmonary artery pressure (mPAP) $25 mm Hg, is associated with an abnormally elevated pulmonary capillary wedge pressure (PCWP) >15 mm Hg or left ventricular end-diastolic pressure (LVEDP) >18 mm Hg (1), it has been variably termed World Health Organization Group 2 PH (1), pulmonary venous hypertension (2), “post-capillary PH” (3), o...

[1] Joint sets within sedimentary basins are commonly interpreted to have formed by tensile failure in conditions where pore fluid pressure was elevated. Such tensile fractures are inferred to be a part of the process that relieves high fluid pressure by locally increasing rock permeability. In spite of the importance of this feedback mechanism, the detailed mechanics of hydraulic fracture gene...