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OBJECTIVE: To investigate whether anion gap (AG) can act as a potentially predictive biomarker in recoveries of neurological and cognitive functions. PATIENTS AND METHODS: A total of 89 patients with intracerebral hemorrhage (ICH) were recruited. Of these, 68 and 21 patients were categorized into screening cohort and validation cohort, respectively. In the screening cohort, patients were categorized into three groups, according to the serum AG levels at admission. We dynamically recorded AG levels. Neurological and cognitive functions were assessed using Glasgow coma scale (GCS), Glasgow outcome scale (GOS) and mini-mental state examination (MMSE) scale at different time points. Furthermore, in the validation cohort, 9 patients with increased AG level underwent interventions to rectify the electrolyte imbalance. RESULTS: In the screening cohort, statistical differences were observed for respiratory diseases (p=0.029) among the three groups. The number of patients in the ≥16 mmol/L group (59.3%) was higher than that in the other groups. The mean scores of GCS in the ≥16 mmol/L group were lower than those in the other groups. The AG levels at admission had significant associations with 180-day GOS (p=0.043) and 180-day MMSE (p=0.001). Among them, the mean scores of the 180-day GOS and 180-day MMSE were lower in the ≥16 mmol/L group than in the other groups. In the validation cohort, AG intervention promoted recoveries of neurological and cognitive functions when compared to those without AG interventions. CONCLUSIONS: AG is a potentially predictive biomarker for the long-term outcomes of ICH patients, and rectifying AG at admission improves the outcomes. [ABSTRACT FROM AUTHOR]

The high frequency impact vibration stress relief (HFIVSR) technology is studied. The S355 steel specimens with large tensile residual stress were prepared by laser surface treatment with a fibre laser, which is used to simulate the welding process. Then the effects of the HFIVSR on residual stress and microstructure for the S355 steel specimens were discussed. In addition, the multi-degree of freedom (DOF) system model of metal particles was developed to reveal the mechanism of the HFIVSR. The experimental results indicate that the tensile residual stress can be effectively eliminated and homogenized by the HFIVSR. The HFIVSR will not change the microstructure of the materials and there are no considerable changes in the grain size for the S355 steel before and after the HFIVSR; furthermore, the HFIVSR can slow down the lattice distortion energy and thus the tensile residual stresses in the S355 steel specimens can be eliminated. The HFIVSR process is expected to be widely used in field of the mechanical engineering. [ABSTRACT FROM AUTHOR]

A novel high frequency vibration weld conditioning (HFVWC) method for relieving the residual stress in fibre laser welded 304 stainless steel is proposed herein. The HFVWC experiments were carried out based the high frequency vibrator system and the mechanism of the residual stress relaxation by the HFVWC method was discussed. The results show that the residual stress of the laser welded 304 stainless steel specimens can be effectively eliminated and homogenized by the HFVWC method; moreover, improving the high frequency vibration energy imposed into the materials can improve the effect of the residual stress relief and homogenization. The residual stress relief mechanism of the HFVWC method can be attributed to the stirring effect induced by the high frequency mechanical vibration and the dislocation activation motion. The findings confirm that the HFVWC method can be used to the industrial application to improve the quality of welded structures. [ABSTRACT FROM AUTHOR]

The ultrasonic stress relief process was introduced to relieve the residual stress in the TC4 titanium alloy subjected to the laser surface irradiation. And the hole drilling method was used to evaluate the residual stress in the TC4 titanium alloy. The results show that the larger tensile residual stress induced by the high energy laser can be effectively relieved by the ultrasonic stress relief. In addition, the effect of the ultrasonic stress relief can be improved by increasing the ultrasonic vibration energy imposed into the TC4 titanium alloy. The findings confirm that the ultrasonic stress relief is promising to be used to relieve the residual stress in TC4 titanium alloy during the processing and manufacturing process. [ABSTRACT FROM AUTHOR]

For a long time, there was no action that a group controller could take during incoming traffic conditions other than returning the elevators back to the main entrance and opening their doors. Passengers would arrive in the main entrance and board the first available elevator car. However, in the early 1990s, sectoring was introduced during incoming traffic conditions.Sectoring is the soft division of the building into groups of (usually but not necessarily contiguous) floors, usually of equal populations. One or more elevators are assigned to a sector. The allocation of the elevator(s) to a sector can either be fixed (static sectoring) or variable (dynamic sectoring) within consecutive round trips. In addition, the size and composition of the different sectors can be static or dynamic.Sectoring is thus a powerful tool in dealing with peaks of incoming traffic demand. However, most of the analysis carried out to understand the effects of sectoring on the performance of the elevator traffic system has been based on simulation only. This paper presents a comprehensive calculation-based analysis of static sectoring control for incoming traffic as a control tool.The analysis is based on the approach of progressively increasing the number of sectors in a building, starting from a single sector (i.e., no sectoring) and proceeding to full sectoring (where the number of sectors equals the number of elevators in the group) and even increasing the number of sectors up to the total number of floors above the main entrance (which has been given the new term: super-sectoring). An analysis is carried out in each case showing the handling capacity, car loading, average waiting time, and average traveling time.Practical application: This paper allows a control system designer to adapt the actions of the controller to the change in passenger arrivals. The control can detect the intensity of passenger arrivals and adjust the number of sectors to suit such an arrival intensity. The aim would be to maximize the handling capacity of the system or minimize the car loading. [ABSTRACT FROM AUTHOR]

The effects produced by the Nd:YAG pulsed laser irradiation on the surface of the AISI 1045 steel were studied and the forming mechanism of the three-dimensional (3-D) surface morphology was proposed and discussed. Meanwhile, the detecting and controlling methods for the thermal damage were proposed. The results show that the transformation of the residual stress state and the surface hardness state can be attributed to the phase-transformation-induced microstructure change. The noticeable sink mark is produced at the Nd:YAG pulsed laser induced thermal damage area owing to the combined effect between the high energy pulsed laser and the surface tensile residual stress field. The findings onfirm that the thermal damage can be detected by acquiring the surface esidual stress, the surface hardness and the surface 3-D morphology; furthermore, the closed-loop control method and the open-loop control method can be applied to control the thermal damage. [ABSTRACT FROM AUTHOR]

The effects of high frequency vibration on residual stress of AISI 1045 steel subjected to pulsed laser surface irradiation were studied. The initial larger tensile residual stress in the specimens was introduced based on the Nd:YAG pulsed-laser machine. Moreover, the residual stress relaxation model was proposed based on the microcosmic dynamic theory in order to reveal the mechanism of the high frequency vibratory stress relief (VSR). The results show that the residual stress in the small workpieces can be eliminated by the high frequency VSR; moreover, increasing the external high frequency vibration energy imposed into the workpieces can improve the effect of the high frequency VSR. The conclusions drawn from the residual stress relaxation model agree well with the conclusions drawn from the experimental results. The findings confirm that the high frequency VSR process is promising to be used to eliminate the residual stress in small workpiece. [ABSTRACT FROM AUTHOR]

Due to the fact that energy partition ratio in grinding is generally higher than other machining processes, surface burn is one of the most common defects in grinding and hard turning of steels. Unfortunately, as grinding is considered to be highly complex, non-stationary and dependent on a large number of input variables, the monitoring of surface burn in grinding process is thus necessary yet difficult. In this work a surface burn production method using high energy density pulsed laser was introduced. Controlled surface burn on various metals was obtained by adjusting laser pulse duration and pulse frequency. Acoustic emission was used for in-process surface burn monitoring. Factors such as laser pulse duration, pulse frequency and sensor mounting location which influence acoustic emission features were also studied. Frequency spectra with and without surface burn were compared. The differences were distinct. It was also found that root mean square (RMS) and mean energy of acoustic emission could successfully reflect the occurrence of surface burn. Findings in this work could provide knowledge for further surface burn monitoring in grinding. [ABSTRACT FROM AUTHOR]