Neutron scattering has shown the first diffraction peak in the structure factor of a 1,4-polybutadiene melt under compression to move to larger q values as expected but to decrease significantly in intensity. Simulations reveal that this behavior does not result from loss of structure in the polymer melt upon compression but rather from the generic effects of differences in the pressure depende...

BACKGROUND Interface pressure and stiffness characterizing the elastic properties of the material are the parameters determining the dosage of compression treatment and should therefore be measured in future clinical trials. OBJECTIVE To provide some recommendations regarding the use of suitable methods for this indication. METHOD This article was formulated based on the results of an inter...

The photoluminescence (PL) and PL excitation (PLE) spectra of the isolated Zn vacancy sVZnd in ZnSe are measured under hydrostatic pressure to 50 kbar at 7 K. The PL band shifts with pressure, roughly 30% faster than the band gap. Compression decreases the Stokes shift, reflecting a reduction in the C3y lattice relaxation around the V 2 Zn site. Defect-molecule calculations show that this arise...

Abbreviations: aBDC, after bottomdead center; aTDC, aft bottomdead center; bTDC, before top dead center; CA50, cra fraction reaches to 50%; CI, compression ignition; COVime indicated mean effective pressure; DI, direct injection; DIS DOI, duration of injection (first DOI1, second DOI2); EGR, homogenous charge compression ignition; IMEP, indicat injection ratio; MPRR, maximum pressure rise rate;...

The gas-filled hollow-core fiber compression and the optical filamentation technique are compared experimentally in a parameter regime suitable for intense few-cycle pulse generation. In particular, pointing stability, spectral properties, and spatial chirp are investigated. It is found that in the case of filamentation, the critical parameter for pointing stability is gas pressure inside the g...

Circular simple shear extrusion process was introduced as a new geometry for simple shear extrusion technique to fabricate ultrafine-grained materials. Similar to the simple shear extrusion method, this process is also based on direct extrusion, and the samples deform in a simple shear manner. In this investigation, the simulations were carried out using the commercial finite element code ABAQU...

This article introduces 2 new cardiopulmonary resuscitation (CPR) concepts: (1) the use of only rhythmic abdominal compression (OAC) to produce blood flow during CPR with ventricular fibrillation and (2) a new way of describing coronary perfusion effectiveness, namely, the area between the aortic and right atrial pressure curves, summed over 1 minute, the units being millimeters of mercury per ...

UNLABELLED The use of an inspiratory impedance threshold valve (ITV) during active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) improves perfusion pressures, and vital organ blood flow. We evaluated the effects of positive end-expiratory pressure (PEEP) on gas exchange, and coronary perfusion pressure gradients during ACD + ITV CPR in a porcine cardiac arrest model. All a...

This study examined the physical properties of six common brands of short-stretch compression bandages used to treat lymphedema. The physical properties examined were (a) maintenance of pressure over a 12-hr period, (b) variability of pressure across the width of the bandages, and (c) variability of pressure when the bandages were wrapped with a 50% overlap. The results of the study indicate th...

background: in patients undergoing mechanical ventilation, mucus production and secretion is high as a result of the endotracheal tube. because endotracheal suction in these patients is essential, chest physiotherapy techniques such as expiratory rib cage compression before endotracheal suctioning can be used as a means to facilitate mobilizing and removing airway secretion and improving alveol...