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Purpose: Central venous catheter (CVC)-related thrombosis (CRT) is a known complication in critically ill patients. However, its clinical significance remains unclear. The objective of the study was to evaluate the occurrence and evolution of CRT from CVC insertion to removal. Methods: A prospective multicenter study was conducted in 28 intensive care units (ICUs). Duplex ultrasound was performed daily from CVC insertion until at least 3 days after CVC removal or before patient discharge from the ICU to detect CRT and to follow its progression. CRT diameter and length were measured and diameter > 7 mm was considered extensive. Results: The study included 1262 patients. The incidence of CRT was 16.9% (95% confidence interval 14.8–18.9%). CRT was most commonly found in the internal jugular vein. The median time from CVC insertion to CRT onset was 4 (2–7) days, and 12% of CRTs occurred on the first day and 82% within 7 days of CVC insertion. CRT diameters > 5 mm and > 7 mm were found in 48% and 30% of thromboses. Over a 7-day follow-up, CRT diameter remained stable when the CVC was in place, whereas it gradually decreased after CVC removal. The ICU length of stay was longer in patients with CRT than in those without CRT, and the mortality was not different. Conclusion: CRT is a frequent complication. It can occur as soon as the CVC is placed and mostly during the first week following catheterization. Half of the thromboses are small but one-third are extensive. They are often non-progressive and may be resolved after CVC removal. [ABSTRACT FROM AUTHOR]

In this retrospective study, we aimed to evaluate the efficacy of percutaneous catheter drainage (PCD) in patients with acute pancreatitis (AP) for management of pancreatic fluid collections (PFCs). A total of 111 AP patients were included with 34 patients in conservative treatment group (received nutrition support and liquid resuscitation during hospitalization) and 77 patients in PCD group (accepted PCD during hospitalization). The APACHE II score, CRP value, procalcitonin (PCT) value, and WBC count of included patients were recorded for further comparison. The inflammation response of patients in both groups was assessed by measuring the mean time for the recovery of CRP level, WBC count, and amylase/lipase. Mortality, length of hospital stay, new-onset ICU admission or readmission, and new-onset multi-organ failure were also compared between the two groups. The pre-conditions of patients in both groups indicate the comparison of the two groups. The inflammatory response in PCD group was attenuated when compared with conservative treatment group evidenced by decreased mean time for recovery of CRP level in PCD group. In addition, patients in PCD groups had less complication rate (multi-organ failure and surgical debridement) than that in conservation treatment group. Patients in conservation treatment group had shorter hospital stay, but failed to achieve statistical significance. Evidence supported that PCD is an effective approach for management of PFCs after conservation treatment failure with decreased complication rate and attenuated inflammation responses. [ABSTRACT FROM AUTHOR]

A uniform nanocoating can substantially enhance the electrochemical properties of cathode materials. Herein, we report that a uniform AlPO4 coating can be produced on the surface of LiNi0.8Co0.15Al0.05O2 (NCA) particles by a homogeneous precipitation method, which was confirmed by scanning electron microscopy and energy dispersive x-ray spectroscopy. After being heated, the AlPO4 was converted to the Li3PO4 which was verified by x-ray diffraction. The heated AlPO4 coated NCA demonstrated a substantially enhanced electrochemical performance. The capacity retention increased from 87.38% for bare NCA to 94.28% for the heated 1 wt.% AlPO4 coated NCA sample. Moreover, the reversible capacity at 5 C increased from 80 mAh/g for bare NCA to 120 mAh/g for the heated 1 wt.% AlPO4-coated NCA. In addition, improved thermal stability was also found. The start temperature of thermal runaway increased from 175.12°C for bare NCA to 200.32°C for the heated 1 wt.% AlPO4-coated NCA. [ABSTRACT FROM AUTHOR]

In this paper, a composite control scheme for macro-micro dual-drive positioning stage with high acceleration and high precision is proposed. The objective of control is to improve the precision by reducing the influence of system vibration and external noise. The positioning stage is composed of voice coil motor (VCM) as macro driver and piezoelectric actuator (PEA) as micro driver. The precision of the macro drive positioning stage is improved by the combined PID control with adaptive Kalman filter (AKF). AKF is used to compensate VCM vibration (as the virtual noise) and the external noise. The control scheme of the micro drive positioning stage is presented as the integrated one with PID and intelligent adaptive inverse control approach to compensate the positioning error caused by macro drive positioning stage. A dynamic recurrent neural networks (DRNN) based inverse control approach is proposed to offset the hysteresis nonlinearity of PEA. Simulations show the positioning precision of macro-micro dual-drive stage is clearly improved via the proposed control scheme. [ABSTRACT FROM AUTHOR]

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formulas of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1H,13C and29Si) and MALDI-TOF MS, and a generic formula of the SSO, T n (OH)x(OR′)y( x, y = 0, 1, 2 ...; n = 1, 2...; T = RSiO1.5− (x+y)/2n). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type. [ABSTRACT FROM AUTHOR]