We investigated the clinical manifestations and course of all probable severe acute respiratory syndrome (SARS) patients in the Vietnam outbreak. Probable SARS cases were defined by using the revised World Health Organization criteria. We systematically reviewed medical records and undertook descriptive statistical analyses. All 62 patients were hospitalized. On admission, the most prominent symptoms were malaise (82.3%) and fever (79.0%). Cough, chest pain, and shortness of breath were present in approximately one quarter of the patients; 79.0% had lymphopenia; 40.3% had thrombocytopenia; 19.4% had leukopenia; and 75.8% showed changes on chest radiograph. Fever developed on the first day of illness onset, and both respiratory symptoms and radiographic changes occurred on day 4. On average, maximal radiographic changes were observed on day 10, and fevers subsided by day 13. Symptoms on admission were nonspecific, although fever, malaise, and lymphopenia were common. The complications of SARS included invasive intubation and ventilation (11.3%) and death (9.7%).

The present study examined the impact of acculturation on intergenerational conflict and support in a sample of Vietnamese American young adults (n = 123). Participants completed a questionnaire that measured demographic characteristics, acculturation, social conflict, and social support. Results indicated that more acculturated Vietnamese young adults, especially young women, were more likely than less acculturated Vietnamese to report being criticized by, and having arguments with, their parents. Intergenerational conflict, however, did not appear to erode supportive exchanges between the two generations, as more acculturated young adults did not differ from their less acculturated counterparts in reporting their parents as a source of support. Results also revealed that increased conflict reported by more acculturated Vietnamese young adults was specific to their relationships with parents and was not present in their relationships with others, a finding that provides evidence for the idea that increased intergenerational conflict in immigrant families might stem from differential acculturation between the two generations.

Carbapenemase-producing Enterobacteriaceae (CPE) are well known to cause many serious infections resulting in increasing mortality rate, treatment cost, and prolonged hospitalization. Among the widely recognized types of carbapenemases, New Delhi β-lactamase (NDM) and Klebsiella pneumoniae carbapenemase (KPC) are the most important enzymes. However, in Vietnam, there are only scattered reports of CPE due to the lack of simple and affordable methods that are suitable to laboratory conditions. This study aims to survey the characteristics of carbapenem-resistant E. coli and K. pneumoniae (CR-E/K) at two hospitals in Southern Vietnam and perform some simple methods to detect the two enzymes. A total of 100 CR-E/K strains were collected from clinical isolates of Gia Dinh People’s Hospital and Dong Nai General Hospital, Vietnam, from November 2017 to May 2018. The patient-related information was also included in the analysis. We conducted real-time polymerase chain reaction (PCR), Modified Hodge Test (MHT), and combined disk test (CDT) on all isolates. Carbapenemase-encoding genes were detected in 47 isolates (36 NDM, 10 KPC, and one isolate harboring both genes). The E. coli strain carrying simultaneously these two genes was the first case reported here. Most of isolates were collected from patients in ICU, Infectious Disease Department, and Department of Urologic Surgery. Urine and sputum were two common specimens. The true positive rate (sensitivity, TPR) and specificity (SPC) of the imipenem–EDTA (ethylen diamine tetra acetic acid) for NDM detection and the imipenem–PBA (phenylboronic acid) for KPC detection on E. coli were 93.8%, 97.1% and 66.7%, 95.7%, respectively. Meanwhile, the imipenem–EDTA for NDM detection and the imipenem–PBA for KPC detection among K. pneumonia achieved 90.5%, 100% and 100%, 92.9% TPR and SPC, respectively. However, MHT showed low sensitivity and specificity. Our findings showed that CP-E/K were detected with high prevalence in the two hospitals. We suggest that CDT can be used as a low-priced and accurate method of detection.

In this paper, dynamic stability analysis and vibration control for a rotating elastic beam connected with an end mass driven by a direct current (DC) motor is considered. A complete strategy including mathematical modeling, dynamic analysis, vibration controller design and simulation for linear and nonlinear systems are presented. Once the rotating flexible physical system has been described by a set of governing partial differential equations, they are manipulated to achieve an appropriate mathematical format for vibration control system design and computer simulation, respectively. Hamilton principle, Lagrange's equation, assumed-modes and the fourth-order Runge–Kutta methods are applied in the system modeling derivation, descretization, and numerical analysis. The correctness of the numerical results and the characteristic property between mathematics and dynamics are demonstrated as well. Also, a realizable vibration control scheme is developed which not only can stabilize all the vibration modes but also make this rotating elastic beam system efficient for good transient response.

A B S T R A C TThe purpose of this study is to clarify whether there are relationships among the four key factors contributing to the success of e-business: e-service quality, e-trust e-customer satisfaction and behavioral intentions, thus make a conclusion and provide better understanding in the field of e-service and e-marketing. This study method used to evaluate and test the scale and theoretical model in the study is quantitative research with sample size N = 476 through the survey to deliver questionnaire directly to subjects. This study examined the scale by confirmatory factor analysis (CFA) and the model of theoretical research by structural equation modeling (SEM). The results of analysis and verification of measurement scales and theoretical research models show that the research scales achieve unidirectional, reliability, convergent validity and high discriminant validity. The hypotheses are accepted at 95% reliability. The study has discovered the new indirect and positive impact of e-service quality on behavioral intentions through mediators e-trust and e-customer satisfaction, as well as other sub relationships, which can be used as foundation for future researches. At the end, managerial implications and recommendations plus contributions are proposed for e-commerce firms, e-marketers and researchers.

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When measuring with an atomic force microscope (AFM), the probe would move to the prescribed position via the platform and its vibration would occur. To achieve precision positioning for the follow-up scanning and high-speed measurement, in this paper, mathematical modeling and control of the probe is focused to avoid the damage incurred by the collision between the probe and the sample and to obtain the high measurement in the scanning step. The Hamilton’s principle is firstly employed to derive the equation of motion and its boundary conditions. Next, the summation method, Lagrangian equation and Laplace transform are applied to obtain natural frequencies, a dynamic model of the AFM probe, and to work out the transfer function of the open-loop system. The proposed model is compared with two conventional AFM probe models: point–mass model and conventional cantilever beam model - where one of the ends of the cantilever and basic platform are assumed to be fixed. Finally, collocated control is exercised to designate the positions for actuator and sensor and the root locus method cooperated with proportional-integral-derivative controllers to simulate the performance of the control system. The result shows that the controller can ensure the stability of this continuous system and perform effective control.

The roller system is an essential and very important part of a lot of fabric processing machines in the textile industry. This study proposes a new bending roller control system (BRCS) to control bending deformation and vibration of the roller system. First, a new mathematical model of a combined roller is obtained by using an eigenfunction expansion method and Timoshenko beam theory. The combined roller consists of inner steel and outer nylon layers to take full advantage and eliminate drawbacks of materials. Second, a hydraulic multi-cylinder system is put inside the roller at the suitable position. This solution not only increases significantly the power of the bending actuation system but also reduces the transient time of dynamic response and avoids damaging outside surfaces of the rollers. Finally, in order to improve dynamic response performance and open wide operating range of system, model predictive control (MPC) and constrained control are applied to the BRCS. Simulation results proved that the proposed control system is completely effective and reliable.