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Is the Serum Vitamin D Level at the Time of Hospital-Acquired Acute Kidney Injury Diagnosis Associated with Prognosis?  [PDF]
Lingyun Lai, Jing Qian, Yanjiao Yang, Qionghong Xie, Huaizhou You, Ying Zhou, Shuai Ma, Chuanming Hao, Yong Gu, Feng Ding
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0064964
Abstract: Background Low circulating vitamin D levels have been suggested to potentially contribute to acute complications in critically ill patients. However, in patients with acute kidney injury (AKI), whether vitamin D deficiency occurs and is a potential contributor to worse early outcomes at the time of AKI diagnosis remains unclear. Methodology/Principal Findings Two hundred patients with AKI were enrolled in our study. Healthy subjects and critically ill patients without AKI served as controls. Serum vitamin D concentrations were measured in the three groups. The patients with AKI were followed up for 90 days and grouped according to median serum vitamin D concentrations. In addition, vitamin D receptor polymorphisms (BsmI and FokI) were measured in these patients; they were also followed up for 90 days and grouped according to vitamin D receptor gene mutations. Low serum 1,25-dihydroxyvitamin D levels (59.56±53.00 pmol/L) were detected in patients with AKI and decreased with increasing severity of AKI. There were no significant findings with respect to 25-hydroxyvitamin D. The 90-day survival curves of individuals with high vitamin D concentrations showed no significant differences compared with the curves of individuals with low concentrations. The survival curves of patients with BB/Bb or FF/Ff genotypes also showed no significant differences compared with patients with bb or ff genotypes. In Cox regression analysis, the vitamin D status in patients with AKI was not an independent prognostic factor as adjusted by age, sex, Sequential Organ Failure Assessment score, or vitamin D receptor polymorphisms. Conclusions/Significance Patients with AKI manifested a marked decrease in the 1,25-dihydroxyvitamin D level at the time of AKI diagnosis, and the degree of 1,25-dihydroxyvitamin D deficiency increased with the severity of AKI. No association between the serum vitamin D level at the time of AKI diagnosis and 90-day all-cause mortality was found in patients with AKI.
Rotordynamic Faults: Recent Advances in Diagnosis and Prognosis  [PDF]
Ryan Walker,Sureshkumar Perinpanayagam,Ian K. Jennions
International Journal of Rotating Machinery , 2013, DOI: 10.1155/2013/856865
Abstract: Diagnosis and condition monitoring in rotating machinery has been a subject of intense research for the last century. Recent developments indicate the drive towards integration of diagnosis and prognosis algorithms in future integrated vehicle health management (IVHM) systems. With this in mind, this paper concentrates on highlighting some of the latest research on common faults in rotating machines. Eight key faults have been described; the selected faults include unbalance, misalignment, rub/looseness, fluid-induced instability, bearing failure, shaft cracks, blade cracks, and shaft bow. Each of these faults has been detailed with regard to sensors, fault identification techniques, localization, prognosis, and modeling. The intent of the paper is to highlight the latest technologies pioneering the drive towards next-generation IVHM systems for rotating machinery. 1. Introduction The topic of diagnosing and prognosing faults in rotating machinery is an ongoing subject of research, with many developments published in a range of conferences and journals annually. This research has the potential to become even more relevant in the coming years due to the rise of IVHM, in which the drive towards condition-based maintenance and whole vehicle monitoring plays a vital role. This paper intends to survey some of the recent developments in the field, with the aim of summarizing some of the more promising studies and trends with relevance to future IVHM systems for rotating machinery. Modern day rotating machines operate with a high level of reliability, and yet the drive for ever increased operation and decreased unscheduled maintenance is providing additional challenges for industry. The airline industry provides a current example of this desire, with airlines pushing manufacturers to enable shorter turnaround times and to keep aircraft in the air longer, increasing cost benefit. Despite the high level of reliability, the rotordynamic faults detailed in this paper remain aspects which require consideration in this drive for increased reliability and improved maintenance procedures [1]. In order to fully understand and summarize the trends and developments in this area, several hundred recent conference and journal papers have been studied. Overall trends have been highlighted and discussed alongside specific papers of relevance. It is intended that the work should provide a broad reference and summary for working engineers on some of the latest developments in rotordynamic fault diagnosis and prognosis, with specific application to papers of industrial
Pulmonary vasoreactivity testing in diagnosis and prognosis of pulmonary hypertension  [cached]
Bülent Mutlu,Burak Hünük,Tar?k K?vrak
Anadolu Kardiyoloji Dergisi , 2010,
Abstract: Right heart catheterization (RHC) is required for confirmation of the diagnosis of pulmonary hypertension (PH) and to asses the prognosis and etiology. Pulmonary vasoreactivity testing (PVT) is one of the most crucial parts of RHC especially in the suitable patient subsets of pulmonary arterial hypertension (PAH) defined by the most recent guidelines. PVT has substantial importance in defining the most appropriate treatment modality. The aim of this review is to provide a comprehensive review of the literature about PVT and the agents used in PVT, to emphasize the importance of this procedure when done with correct indications with a correct technique and to contribute in the accurate management of PH patients.
A Methodology to Develop the Integration of the Environmental Management System with Other Standardized Management Systems  [PDF]
Manuel Ferreira Rebelo, Gilberto Santos, Rui Silva
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2014, DOI: 10.4236/cweee.2014.34018
Abstract: Traditionally the global management system of an organization is frequently split into a number of individual management systems that are defined and implemented according to specific management systems standards (MSSs) as well as managed independently. The individual implementation of MSSs is an option that leads to several inefficiencies and sub-optimization of the global management system of an organization. As referred by ISO [1] the interested parties’ requirements increase. A more effective and efficient option for an organization is to integrate, into an integrated management system (IMS), the implementation and management of requirements of multiple MSSs. Certain difficulties are associated to the structuring process, implementation, verification, evaluation, improvement and progressive development of an IMS in the organizations. Several scholars have proposed various theoretical approaches regarding the integration of individual management systems (MSs) leading to the conclusion that there is not a common practice for all organizations as they encompass different characteristics. This paper aims to present and justify a designed methodology to be used by organizations to support the integration of various MSs. Among them are highlighted: the Environmental Management System (EMS) according ISO 14001 [2], the Quality Management System (QMS) according ISO 9001 [3], and the Occupational Health and Safety Management System (OH & SMS) according OHSAS 18001 [4]. The methodology was designed in the context of a Portuguese company, on sequence of an organizational diagnosis and a research that was performed through a questionnaire. The strategy and the research methods took into consideration the case study.
MicroRNAs in the diagnosis, prognosis and treatment of cancer  [cached]
Violaine Havelange,Catherine E.A. Heaphy,Ramiro Garzon
Oncology Reviews , 2011, DOI: 10.4081/128
Abstract: MicroRNAs (miRNAs) are small non-coding RNAs that regulate critical cell processes such as cell proliferation, apoptosis and differentiation by modulating gene expression. MiRNAs deregulation has been observed extensively in cancer. Elegant studies have demonstrated that miRNAs are involved in the initiation and progression of several malignancies. In this review we will address the role of miRNAs in the diagnosis and prognosis of cancer. The development of new drugs mimicking or blocking miRNAs will be discussed.
An Integrated Framework for Diagnosis and Prognosis of Hybrid Systems  [PDF]
Elodie Chanthery,Pauline Ribot
Computer Science , 2013, DOI: 10.4204/EPTCS.124.4
Abstract: Complex systems are naturally hybrid: their dynamic behavior is both continuous and discrete. For these systems, maintenance and repair are an increasing part of the total cost of final product. Efficient diagnosis and prognosis techniques have to be adopted to detect, isolate and anticipate faults. This paper presents an original integrated theoretical framework for diagnosis and prognosis of hybrid systems. The formalism used for hybrid diagnosis is enriched in order to be able to follow the evolution of an aging law for each fault of the system. The paper presents a methodology for interleaving diagnosis and prognosis in a hybrid framework.
Situation-Aware Integration and Transmission of Safety Information for Smart Railway Vehicles  [PDF]
Hanul Yeon,Dongsoo Har
Computer Science , 2015,
Abstract: Recent trend of railway train development can be characterized in several aspects : high speed, infortainment, intelligence in driving, and so on. In particular, trend of high speed in driving is prominent and competition for high speed amongst several techno-savvy countries is becoming severe. To achieve high speed, engines or motors are distributed over multiple vehicles of train to provide increased motive power, while a single engine or motor has been mostly used for conventional trains. Increased speed and more complicated powertrain system naturally incur much higher chance of massive accidents. From this perspective, importance of proactive safety control before accident takes place cannot be over-emphasized. To implement proactive safety control requires situation-aware integration and transmission of safety information obtained from IoT sensors. Types of critical IoT sensors depend on situational conditions. Thus, integration and transmission of safety information should be performed with IoT sensors providing the safety information proper for faced situation. This brief paper is to devise a methodology how to operate IoT sensor network enabling proactive safety control for railway vehicles and to propose a queue management based medium access control scheme.
Influence of safety culture on the safety level in chosen enterprise  [PDF]
W. Wolany,M. Spilka
Journal of Achievements in Materials and Manufacturing Engineering , 2011,
Abstract: Purpose: In this paper was carried out the analysis of influence of safety culture, connected with implementation Occupational Health and Safety Management System, on safety level in chosen enterprise. The organizational practices necessary for the effective formulation and maintenance of high safety culture were characterized.Design/methodology/approach: The concept of health and safety at work legislation was defined and the idea of safety culture was discussed. Moreover, the necessity of continuous improvement according to PN-N-18001 standard was showed. In this paper was talked over the problem of accidents and occupational diseases among coal miners, who work in a huge and rich in dangers area.Findings: According to continuous improvement principles is the necessity of monitoring work conditions, conducting regular audits and organizing training courses, which lead to developing high safety culture.Practical implications: Developing of the safety culture brings some profits as reducing numbers of heavy and fatal accidents, increasing the number of detect occupational diseases. The enterprise, which developing high safety culture can expect from employees greater caution and respect for rules and instructions bench.Originality/value: The article indicated that the coal mines needs effective actions which should be directed on increase supervision in workplaces and reducing threats causing industrial accidents. The essence of safety culture was presented.
DNA microarrays in cancer diagnosis and prognosis
Oswaldo Keith Okamoto
Einstein (S?o Paulo) , 2005,
Abstract: This review discusses recent advances in our understanding ofthe human genome and the application of derived technologies inthe medical area. It focuses on the use of DNA microarray fordiagnosis, prognosis, and therapeutic purposes in oncology, andthe resultant impact it might have on routine clinical practice.
A Fault Prognosis Strategy Based on Time-Delayed Digraph Model and Principal Component Analysis  [PDF]
Ningyun Lu,Bin Jiang,Lei Wang,Jianhua Lu,Xi Chen
Mathematical Problems in Engineering , 2012, DOI: 10.1155/2012/937196
Abstract: Because of the interlinking of process equipments in process industry, event information may propagate through the plant and affect a lot of downstream process variables. Specifying the causality and estimating the time delays among process variables are critically important for data-driven fault prognosis. They are not only helpful to find the root cause when a plant-wide disturbance occurs, but to reveal the evolution of an abnormal event propagating through the plant. This paper concerns with the information flow directionality and time-delay estimation problems in process industry and presents an information synchronization technique to assist fault prognosis. Time-delayed mutual information (TDMI) is used for both causality analysis and time-delay estimation. To represent causality structure of high-dimensional process variables, a time-delayed signed digraph (TD-SDG) model is developed. Then, a general fault prognosis strategy is developed based on the TD-SDG model and principle component analysis (PCA). The proposed method is applied to an air separation unit and has achieved satisfying results in predicting the frequently occurred “nitrogen-block” fault. 1. Introduction The desire and need for accurate diagnostic and real predictive prognostic capabilities are apparent in process industry. Detecting potential problems quickly and diagnosing them accurately before they become serious can significantly increase process safety, reduce production costs, and guarantee product quality. From the aspects of methodology and technology, it involves fault detection, fault diagnosis, and fault prognosis (the three major tasks of prognostics and health management (PHM) systems). Fault prognosis is the most difficult one, since it requires the ability to acquire knowledge about events before they actually occur [1]. There has been much more progress made in fault detection and diagnosis than in prognosis [2–5]. Despite the difficulties, some impressive achievements have been made in fault prognosis, which has been approached via a variety of techniques, including model-based methods such as time-series prediction, Kalman filtering, and physics or empirical-based methods; probabilistic/statistical methods such as Bayesian estimation, the Weibull model; data-driven prediction techniques such as neural network. References [1, 4, 5] had given comprehensive surveys on those fault prognosis methods. For process industry, quantitatively data-driven methods are more attractive, because accurate analytical models are usually unavailable due to process complexity,
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