The weekend effect:does time of admission impact management and outcomes of small bowel obstruction?

Aims:To determine whether day and time of admission influences the practice patterns of the admitting general surgeon and subsequent outcomes for patients diagnosed with small bowel obstruction.Methods:A retrospective database review was carried out,covering patients admitted with the presumed diagnosis of partial small bowel obstruction from 2004–2011.Results:A total of 404 patients met the inclusion criteria.One hundred and thirty-nine were admitted during the day,93 at night and 172 on the weekend.Overall 30.2%of the patients were managed operatively with no significant difference between the groups(P=0.89);however,of patients taken to the operating room,patients admitted during the day received operative intervention over 24 hours earlier than those admitted at a weekend,0.79 days vs 1.90 days,respectively(P=0.05).Overall mortality was low at 1.7%,with no difference noted between the groups(P=0.35).Likewise there was no difference in morbidity rates between the three groups(P=0.90).Conclusions:Despite a faster time to operative intervention in those patients admitted during the day,our study revealed that time of admission does not appear to correlate to patient outcome or mortality.

Event-triggered finite-time guaranteed cost control of asynchronous switched systems under the round-robin protocol via an AED-ADT method

This paper focuses on addressing the problems of finite-time boundedness and guaranteed cost control in switched systems under asynchronous switching.To reduce redundant information transmission and alleviate data congestion of sensor nodes,two schemes are proposed:the event-triggered scheme(ETS)and the round-robin protocol(RRP).These schemes are designed to ensure that the system exhibits good dynamic characteristics while reducing communication resources.In the field of finite-time control,a switching signal is designed using the admissible edge-dependent average dwell time(AED-ADT)method.This method involves a slow AED-ADT switching and a fast AED-ADT switching,which are respectively suitable for finite-time stable and finite-time unstable situations of the controlled system within the asynchronous switching interval.By constructing a double-mode dependent Lyapunov function,the finite-time bounded criterion and the controller gain of the switched systems are obtained.Finally,the validity of the proposed results is showcased by implementing a buck-boost voltage circuit model.

Stabilization of switched linear systems under asynchronous switching subject to admissible edge-dependent average dwell time

The problem of stabilizing switched linear systems under asynchronous switching is addressed.The admissible edge-dependent average dwell time method is applied to design a switching signal that comprises slow admissible edge-dependent average dwell time and fast admissible edge-dependent average dwell time.Under this switching signal,the restriction that the maximum delay of asynchronous switching is known in advance is removed.The constructed Lyapunov function is associated with both the system mode and controller mode.The stabilization criteria and the corresponding algorithm are presented to obtain the controller gains and to design the switching signal.Finally,two examples are given to demonstrate the effectiveness of the proposed results.