Characteristic of Ambulatory Blood Pressure in Normotensive Subjects With Type 2 Diabetes Mellitus

Objectives To observe the characteristic of ambulatory blood pressure monitoring in normotensive diabetic subjects with normoalbuminuria or microalbuminuria. Methods Fifty-two normotensive patients with type 2 diabetes received ambulatory blood pressure monitoring were divided into normoalbuminuric and microalbuminuric groups according to their albumin excretion rate, the other 28 normotensive subjects without diabetes were contributed as control group. Ambulatory blood pressure monitoring was performed on a working day and measurement of blood pressure circadian rhythm was analyzed. Results Normotensive microalbuminuric diabetic patients had higher night-time systolic blood pressure and more blood pressure burden than normotensive normoalbuminuric diabetic patients. Additionally, the microalbuminuric patients had a higher frequency of non-dippers than normoalbuminuric ones, although they were all normotensive. Compared to the normotensive non-diabetic control subjects, the night- time systolic blood pressure and frequency of non- dippers of the normoalbuminuric diabetic patients were significantly higher. Conclusions Intensive attention should be paid in control of blood pressure in diabetic patients to prevent and limit damage of target organ including kidney, even in those normotensive subjects.

Effects of atomization parameters of dust removal nozzles on the de-dusting results for different dust sources

In order to obtain appropriate spray pressure and enhance the spraying and dust removal efficiency, various factors including the dust characteristics, nozzle spraying angle, effective spraying range, water consumption and droplet size are taken into account. The dust characteristics from different mines and atomization parameters of different pressure nozzles were measured. It was found that the internal pressure of coal cutters and roadheaders should be kept at 2 MPa, which could ensure large droplet size, large spraying angle and low water consumption and hence realizing a large-area covering and capture for large particle dusts. However, the external spray pressure should be kept at 4 MPa for smaller droplet size and longer effective spraying range, leading to effective dust removal in the operator zone. The spray pressure of support moving, drawing opening, and stage loader on a fully mechanized caving face and stage loader on a fully mechanized driving face should be kept at 8 MPa, under which the nozzles have long effective spraying range, high water flow and small droplet size for the rapid capture of instantaneous, high-concentration and small size dust groups. From the applications on the caving and driving faces in the coal mines, it is indicated that the optimization of spray pressure in different spraying positions could effectively enhance dust removal efficiency. Selecting appropriate nozzles according to the dust characteristics at different positions is also favorable for dust removal efficiency. With the selected nozzles under optimal pressures, the removal rates of both total dust and respirable dust could reach over70%, showing a significant de-dusting effect.

Rate decline analysis of multiple fractured horizontal well in shale reservoir with triple continuum

Multiple fractured horizontal well(MFHW) is widely applied in the development of shale gas. To investigate the gas flow characteristics in shale, based on a new dual mechanism triple continuum model, an analytical solution for MFHW surrounded by stimulated reservoir volume(SRV) was presented. Pressure and pressure derivative curves were used to identify the characteristics of flow regimes in shale. Blasingame type curves were established to evaluate the effects of sensitive parameters on rate decline curves, which indicates that the whole flow regimes could be divided into transient flow, feeding flow, and pseudo steady state flow. In feeding flow regime, the production of gas well is gradually fed by adsorbed gases in sub matrix, and free gases in matrix. The proportion of different gas sources to well production is determined by such parameters as storability ratios of triple continuum, transmissibility coefficients controlled by dual flow mechanism and fracture conductivity.