ABSTRACT
This paper presents an experimental study to assess the behaviour of coal samples under tensile loadings to better understand the failure mechanisms and the interactions with the coal characteristics. A set of Brazilian splitting tests were carried out using disk specimens obtained from Tashan Coal Mine in China. The digital speckle correlation method and acoustic emission (AE) were used to capture the deformation localisation and AE characteristics of each specimen during the loading process. The precursor characteristics of AE and the failure mechanism are discussed. It was found that the entire loading process mainly consists of compaction, elastic and post-peak dropping stage without an obvious yielding stage. Two kinds of deformation localisation were observed: central symmetry and axis symmetry. The corresponding AE evolution patterns have different phases, including gradual rise, step rise, transient rise and steady rise. During the subcritical failure stage, AE counts demonstrate a "rapidly increasing + flatten" intermittent feature. The results provide a reference for a better understanding of the damage process of the brittle coal material and its application in ground control design.
ABSTRACT
ABSTRACT This study was designed to explore the pharmacokinetic regularity of the plasma concentration, tissue distribution and excretion of orcinol glucoside from aqueous extracts of raw and processed Curculigo orchioides Gaertn., Hypoxidaceae. The experiment first used an ultrahigh-performance liquid chromatography-tandem mass spectrometry approach with multiple reaction monitoring and a positive mode to separate orcinol glucoside from naringin to obtain the plasma concentration curves, bar graph of tissue distribution and excretion curves. These results might be beneficial for reasonable clinical application of C. orchioides and for further development of its wine and salt-processing mechanism.
ABSTRACT
OBJECTIVE: To investigate the efficacy and safety of selective head cooling with mild systemic hypothermia in hypoxic-ischemic encephalopathy (HIE) in newborn infants. STUDY DESIGN: Infants with HIE were randomly assigned to the selective head cooling or control group. Selective head cooling was initiated within 6 hours after birth to a nasopharyngeal temperature of 34 degrees+/-0.2 degrees C and rectal temperature of 34.5 degrees to 35.0 degrees C for 72 hours. Rectal temperature was maintained at 36.0 degrees to 37.5 degrees C in the control group. Neurodevelopmental outcome was assessed at 18 months of age. The primary outcome was a combined end point of death and severe disability. RESULTS: One hundred ninety-four infants were available for analysis (100 and 94 infants in the selective head cooling and control group, respectively). For the selective head cooling and control groups, respectively, the combined outcome of death and severe disability was 31% and 49% (OR: 0.47; 95% CI: 0.26-0.84; P=.01), the mortality rate was 20% and 29% (OR:0.62; 95% CI: 0.32-1.20; P=.16), and the severe disability rate was 14% (11/80) and 28% (19/67) (OR: 0.40; 95% CI: 0.17-0.92; P=.01). CONCLUSIONS: Selective head cooling combined with mild systemic hypothermia for 72 hours may significantly decrease the combined outcome of severe disability and death, as well as severe disability.