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Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an adjunct procedure designed to sustain the circulation until definitive hemostasis is obtained. The device is indicated in trauma patients with abdominal trauma and/or pelvic fractures, but there is limited evidence for its use in gastrointestinal bleeding. A 76-year-old woman was admitted to the emergency department of our hospital because of shock, manifesting as hematemesis. We performed emergency endoscopy and detected active bleeding from a gastric ulcer. Achieving hemostasis was difficult, and she experienced shock again during the procedure, leading to cardiopulmonary arrest. REBOA was performed after the return of spontaneous circulation because she continued to be in a state of shock. Her blood pressure rose, and endoscopic hemostasis was continued with balloon inflation, but it didn't stop the bleeding completely, so we shifted to emergency laparotomy and performed suture hemostasis. The patient developed no postoperative complications and was transferred to another hospital. REBOA can be effective at improving the hemodynamic status in patients with uncontrollable gastrointestinal bleeding.

Management of early nutrition plays an important role in the treatment of acute pancreatitis patients, but the sample sizes of randomized control trials that have compared enteral and parental nutrition were small. From the data of Diagnostic Procedure Combination, we identified patients who had been diagnosed with acute pancreatitis and discharged from the hospital between 2014 and 2015. We compared the length of hospital stay and hospital mortality among patients with acute pancreatitis that was managed with and without enteral nutrition within 7 days from hospitalization. The results showed a significant decrease in the in-hospital mortality rate of 56% (odds ratio 0.444, 95% confidence interval [CI] 0.358 - 0.551, P

In the process of closing three-phase vacuum circuit breakers (VCBs), the collisions between the contacts in the vacuum interrupters cause the contacts to bounce. Consequently, repetition of make-and-break of the electrical circuit happens. If the duration of this phenomenon exceeds a certain time length, the surfaces of the contacts are damaged by the heat of the arcs between the contacts. This causes deterioration of the intrinsic functions of the VCB.

We present a technique for modeling dynamic characteristics of a vacuum circuit breaker. In the first part of this paper, the structural dynamics and vibration characteristics of a vacuum circuit breaker are experimentally examined. From these results, a structural dynamic model of tripping is formulated with consideration of the impact phenomenon. The results of the numerical simulation using the initial design variables are compared with experimental results. The effect of design variables such as speed and overshoot of a moving contact for tripping are discussed. Finally a guiding principle to determine the design variables is proposed to optimize the dynamic characteristics of a vacuum circuit breaker.

In frequency response function (FRF) estimation for modal testing, determining reference locations, namely exciting positions or exciting directions, is one of the most important subjects. If a suitable reference location is not selected, it is difficult to extract the correct structural modes from the FRF database of the system. In this paper, a method for processing estimated FRF data to select appropriate response locations is proposed. This method is based on an evaluation of the squared norm functions of FRF vectors, which are estimated by single-input multiple-output vibration testing. In this FRF estimation, the exciting locations are moved, and the squared norm functions corresponding to the exciting locations are obtained. The best input location for maximizing the Euclidean norm of a response vector or that for minimizing the angle between a certain eigenmode and the response vector can be found by comparing of these functions. The validity of the method was discussed on the basis of the results of examples applied to a numerical structural model and to a real structure. This implies that the proposed method is a practical one for selecting reference locations for modal testing in a short period of time.

Let Q be a semi-regular local ring of dimension d, m be its maximal ideal, and q be an m-primary ideal. Then LQ(Q/qn+1), the length of Q-module Q/qn+1, is equal to the characteristic polynomial PQ(q,n) in n for a sufficiently large value of n:where ei = ei(q), i = 0,1,2,…, d are integers uniquely determined by q, called normalized Hilbert coefficients of q according to (1). It was shown in (1) that e1(q) is a non-negative integer, and is equal to zero if and only if q is generated by a system of parameters. We shall prove, in this paper, that e2(q) is also a non-negative integer, and that this non-negativity is not necessarily true for other coefficients. We shall give an example with negative e3(q).

An approach to prevent noises of large induction motors which are subjected to various forms of vibration caused by electromagnetic exciting forces is presented. From the results obtained in experimental investigations for many actual large motors, it has become clear that all the components of the noise and vibration paths from exciting point to radiational sound field must be taken into consideration for avoiding typical peak noise and vibration. A substructural system analysis is adopted to comprehend the vibrational behavior of all components by using FFT (fast Fourier transform) analysis and the transfer function method. The combined system simulation is done in a digital computer by using modal parameters to estimate the frequency response of the total structure. It means that the contributions of each component to the total noise and vibration are predicted without actual motors. Now, through this investigation, it is considered possible to predict quantitatively the effects of each component al le...