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Scenedesmus quadricauda, a local freshwater microalga, was used to treat primary settled and filtrate wastewater and to produce algal lipid. For the primary settled wastewater, the maximum biomass concentrations of acclimated and unacclimated microalgae were 0.995 g/L and 0.940 g/L, respectively. Over 90% orthophosphate and 95% ammonia nitrogen in the acclimated and unacclimated cultures, respectively, were removed after five days. The lipid contents of the microalgae were higher than 13% in all cultures. The highest growth rate occurred in the 25% filtrate culture. Over 80% phosphate was removed under the 25% and 50% filtrate cultures within six days, while over 90% ammonia nitrogen was removed within five days under both conditions. The lipid content was the highest (18.1%) under the 50% filtrate condition. 06:0, C18:2n6, and C18:3n3 were dominant fatty acids. In conclusion, S. quadricauda is a viable candidate for wastewater treatment and lipid production. [ABSTRACT FROM AUTHOR]

Background and purpose Both blood pressure ( BP) and its variability ( BPV) are established risk factors for development of atherosclerotic disease and are associated with an increased risk for cardiovascular and all-cause mortality. The prognostic implications of outpatient clinic visit-to-visit BPV amongst patients with lacunar infarction are nevertheless unknown. Methods The clinical outcome of 281 patients with lacunar infarction was prospectively followed up. The average BP and BPV, as determined by the standard deviation of the systolic and diastolic BP, were recorded during a mean 13 ± 6 outpatient clinic visits. Results The mean age of the population was 70 ± 10 years. After a mean 78 ± 18 months follow-up, 65 patients died (23%), 31% (20/65) due to cardiovascular causes; 14% and 7% developed recurrent stroke and acute coronary syndrome. After adjusting for age, sex, mean systolic and diastolic BP, cardiovascular risk factors and comorbidities, patients with a systolic BPV of the third tertile had significantly higher risk of all-cause mortality [hazard ratio ( HR) 1.97, 95% confidence interval ( CI) 1.02-3.80, P = 0.04) and cardiovascular mortality ( HR 7.64, 95% CI 1.65-35.41, P < 0.01) than those with systolic BPV of the first tertile. Nevertheless, systolic BPV did not predict recurrent stroke or acute coronary syndrome. Diastolic BPV did not predict various adverse clinical outcomes. Conclusions Visit-to-visit systolic BPV predicts long-term all-cause and cardiovascular mortality after lacunar infarct, independent of conventional risk factors including average BP control. [ABSTRACT FROM AUTHOR]

In recent years, the increasing complexity of process plants and other engineered systems has extended the scope of interest in control engineering, which was previously focused on the development of controllers for specified performance criteria such as stability and precision. Modern industrial systems require a higher demand of system reliability, safety, and low-cost operation, which in turn call for sophisticated and elegant fault-detection and isolation algorithms. This paper develops an intelligent supervisory coordinator (ISC) for process supervision and fault diagnosis in dynamic physical systems. A qualitative bond graph modeling scheme, integrating artificial-intelligence techniques with control engineering, is used to construct the knowledge base of the ISC. A supervisor provided by the ISC utilizes the knowledge in the knowledge base to classify various system behaviors, coordinates different control tasks (e.g., fault diagnosis), and communicates system states to human operators. The ISC provides a robust semiautonomous system to assist human operators in managing dynamic physical systems. The proposed ISC has been successfully applied to supervise a laboratory-scale servo-tank liquid process rig. [ABSTRACT FROM AUTHOR]

Background: Matrix metalloproteinases (MMPs) play pivotal roles in tumor progression. MMP-13 (collagenase-3) digests collagen and other extracellular components. Materials and Methods: Reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry and zymograph were used to study the roles of MMP-13 during the neoplastic process of oral squamous cell carcinoma (OSCC). Results: Increase of MMP-13 mRNA and protein expression in OSCC cell lines relative to cultivated normal oral keratinocytes was found. MMP-13 mRNA expression in OSCC was significantly higher than in non-cancerous match tissue (NCMT) in 36 tissue pairs. Esophageal squamous cell carcinoma also exhibited high MMP-13 mRNA expression. The percentage of OSCC exhibiting strong MMP-13 immunoreactivity was significantly higher than pre-invasive lesion and NCMT. Treatment with >5 μm epigallocatechin-3-gallate (EGCG) to OEC-M1 cells suppressed the expression and activity of MMP-13. Conclusion: MMP-13 could be a potential tumor marker for OSCC. The effects of EGCG in tumor inhibition may act partially through the modulation of MMP-13. [ABSTRACT FROM AUTHOR]

Background: Oral squamous cell carcinoma (OSCC) is a worldwide problem. The main mechanism of tumor immunity is the destruction of tumor cells by cytolytic T lymphocytes. Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4; CD152), a negative regulator of T-lymphocyte activation, plays an extremely important role in the immune tolerance and anergy. This study was designed to investigate the role of CTLA-4 polymorphism in OSCC. Methods: The CTLA-4 +49 A/G polymorphism was studied in 118 patients with OSCC and 147 healthy controls by using restriction fragment length polymorphism (RFLP). The genotype and phenotype frequencies were evaluated in Fisher's exact test. Results: There was no significant difference in the frequency of CTLA-4 polymorphism between the OSCC study group and healthy controls. The CTLA-4 A/A genotype was significantly associated with a younger age of onset of OSCC ( P = 0.04). The AA genotype was associated with significantly poorer survival ( P = 0.003). Conclusion: The present study is the first to shows that the A/A polymorphism is associated with poor survival in OSCC in Taiwan. [ABSTRACT FROM AUTHOR]

We explored the feasibility and efficacy of an exercise programme for elderly people with knee pain conducted via videoconferencing. Twenty-two community-dwelling subjects aged 60 years or above with knee pain were recruited from two community centres in Hong Kong. A 12-week exercise programme, including strengthening and balance training, was given via videoconferencing to subjects at both centres, in conjunction with a home-based exercise programme. The outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), quadriceps muscle strength, Berg's Balance Scale (BBS) and subjects' degree of acceptance of videoconferencing. Twenty subjects completed the 12-week programme and significant improvements occurred in all domains of the WOMAC score (P <0.003). There was a 44% and a 13% increase in quadriceps muscle strength (P <0.001) and BBS (P <0.001), respectively. Over 80% of the elderly subjects who joined the programme agreed or strongly agreed about all aspects of using videoconferencing. Most of them felt that the system was user-friendly and convenient. Videoconferencing appears to be a useful method of delivering a resistance-training programme for community-dwelling elderly persons with knee pain. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To identify exercise test variables that can improve the positive predictive value of exercise testing in women. DESIGN: Cohort study. SETTING: Regional cardiothoracic centre. SUBJECTS: 1286 women and 1801 men referred by primary care physicians to a rapid access chest pain clinic, of whom 160 women and 406 men had ST depression of at least 1 mm during exercise testing. The results for 136 women and 124 men with positive exercise tests were analysed. MAIN OUTCOME MEASURES: The proportion of women with a positive exercise test who could be identified as being at low risk for prognostic coronary heart disease and the resulting improvement in the positive predictive value. RESULTS: Independently of age, an exercise time of more than six minutes, a maximum heart rate of more than 150 beats/min, and an ST recovery time of less than one minute were the variables that best identified women at low risk. One to three of these variables identified between 11.8% and 41.2% of women as being at low risk, with a risk for prognostic disease of between 0-11.5%. The positive predictive value for the remaining women was improved from 47.8% up to 61.5%, and the number of normal angiograms was potentially reducible by between 21.1-54.9%. By the same criteria, men had higher risks for prognostic disease. CONCLUSIONS: A strategy of discriminating true from false positive exercise tests is worthwhile in women but less successful in men. [ABSTRACT FROM AUTHOR]

As data sets in qualitative models are not always available, one of the approaches for economic prediction is to apply causal reasoning methods to qualitative models. Generally speaking, economists typically make use of causal reasoning and comparative statics during predictions. Immediate effects (i.e. dynamics) are not considered very important if the disturbances are not very large and the system remains stable. For linear systems, long term (comparative) effects, such as the shifted equilibrium, can be predicted by causal ordering together with Mason's rule or the signal flow-graph reduction method. However, for systems with general monotonic functions, the qualitative flow-graph simplification technique proposed in this paper should be used. Comparisons are made between our newly proposed monotonic function qualitative flow-graph approach and other analytical and artificial intelligence methods. [ABSTRACT FROM AUTHOR]

Abstract Extensive studies involving multilevel loading have been performed to study the interaction effects of High–Low and Low–High loading sequences on various metals. 1–10 High–Low sequences generally yield ‘damage’ sums less than unity while ‘damage’ sums for Low–High sequences are typically > 1. It can be appreciated that the mechanisms governing fatigue behaviour under elastically dominant conditions differ from those observed under predominantly plastic conditions. This paper presents results on the interaction between plastically dominant fatigue (PDF) and elastically dominant fatigue (EDF) in 316L stainless steel and 6061-T6 aluminium alloy. In addition, overstraining effects coupled with PDF and EDF interaction in 316L stainless steel are also reported. [ABSTRACT FROM AUTHOR]

The capability to acquire the position and orientation of an autonomous mobile robot is an important element for achieving specific tasks requiring autonomous exploration of the workplace. In this paper, we present a localization method that is based on a fuzzy tuned extended Kalman filter (FT-EKF) without a priori knowledge of the state noise model. The proposed algorithm is employed in a mobile robot equipped with 16 Polaroid sonar sensors and tested in a structured indoor environment. The state noise model is estimated and adapted by a fuzzy rule-based scheme. The proposed algorithm is compared with other EKF localization methods through simulations and experiments. The simulation and experimental studies demonstrate the improved performance of the proposed FT-EKF localization method over those using the conventional EKF algorithm. [ABSTRACT FROM AUTHOR]

This paper presents a segment-detection and grouping scheme that allows incremental and on-line learning of indoor environment maps by mobile robots. The proposed algorithm is based on authors' earlier work of modeling the environment by Enhanced Adaptive Fuzzy Clustering (EAFC) algorithm along with Noise Clustering (NC). In this study, the modeling is refined by first dividing the world into discrete regions as local models. Then, the line segments in local and global models are grouped together by a hierarchical fuzzy system. Adjusting the membership functions that establish the grouping criteria controls the degree of approximation in such combination. The presented map building method for modeling an indoor office environment has successfully been implemented in real-time and tested on Pioneer 2DX mobile robot equipped with sonar sensors. The experimental studies demonstrate improved performance through continuous maps that are obtained by adopting the fuzzy system during the grouping of line segments within local and global models. [ABSTRACT FROM AUTHOR]

The new acceleration control scheme aims to give an inverter-fed induction motor excellent dynamic performance by using an on-line inference controller. In every time interval of the control process, the acceleration increments produced by two different voltage vectors are compared, yielding one optimum stator voltage vector that is selected and retained. The on-line inference control is built using a production system and some heuristic knowledge about the relationship between the motor voltage and acceleration. Because integral calculation and motor parameters are not involved, the new controller has no accumulation error of integral, as in the conventional vector control schemes, and it can be used for different induction motors without modification. [ABSTRACT FROM AUTHOR]

Objective: To evaluate psychometric properties of the Chinese version of Dementia Quality of Life Measure - Proxy (C-DEMQoL-Proxy). Methods: Care home residents aged ≥60 years who were diagnosed with dementia or demonstrated impairment in cognition were recruited from four care facilities in Hong Kong. Caregivers of these participants were also invited to participate. The original DEMQoL-Proxy was translated into Chinese (Cantonese) by a trained translator. The forward-translated version was reviewed by an expert panel of six experienced healthcare professionals. Revisions were made based on comments. The instrument was back-translated to English to check whether further changes were necessary. Demographic data (age, sex, type and severity of dementia, and Mini-Mental State Examination [MMSE] score) were collected from medical records of participants with dementia. Caregivers were interviewed by an occupational therapist or personnel supervised by the occupational therapist using the C-DEMQoL-Proxy and the Chinese version of Quality of Life-Alzheimer's Disease-Proxy (C-QoL-AD-Proxy). Acceptability, reliability, and validity of the C-DEMQoL-Proxy were evaluated using standard psychometric methods. Results: 90 individuals (82.2% women) with dementia aged 72 to 102 years were included. Their diagnosis included Alzheimer's disease (23.3%), vascular dementia (15.6%), mixed and other types of dementias (51.1%), and missing (10%). Severity was mild in 12.2%, moderate in 62.2%, and severe in 25.6%. The mean MMSE score was 12.0 ± 4.9. 20% of the caregivers were family members and the rest were professional carers. The C-DEMQoL-Proxy had good acceptability, with no floor or ceiling effects or missing data. It had good internal consistency (Cronbach alpha = 0.91) and test-retest reliability (intraclass correlation coefficients = 0.83). It was mildly correlated with C-QoL-AD-Proxy (r = 0.29, p < 0.01). Age and sex were not correlated with C-DEMQoL-Proxy scores. C-DEMQoL-Proxy scores were not significantly different between dementia types, severity levels, or between those with higher or lower MMSE scores. Conclusion: The C-DEMQoL-Proxy is a valid and reliable instrument to assess health-related quality of life in individuals with dementia. [ABSTRACT FROM AUTHOR]

Discusses the influence of finite surface recombination velocity on the proper interpretation of photoconductive decay (PCD) transients in semiconductors. Consideration of the limitations of simple analytical equations which relate the observed effective lifetime to the material parameters; Proposed methods to extract information from PCD experiments; Conclusion.

With increasing emphasis on patient autonomy, patients are encouraged to be more involved in end-of-life issues, including the use of extraordinary efforts to prolong their lives. Being able to make anticipatory decisions is seen to promote autonomy, empower patients and optimise patient care. To facilitate shared decision-making, patients need to have a clear and accurate understanding of cardiopulmonary resuscitation (CPR). This study aims to understand the knowledge and perspectives of the local community regarding resuscitation options and end-of-life decision-making and to explore ways to improve the quality of end-of-life discussions. An interviewer-administered survey was conducted with a prospectively recruited group of surgical patients admitted postoperatively to the day surgery ward of a single tertiary institution in Singapore from April to May 2015. The survey, modelled after two validated questionnaires, measured patients' knowledge, attitudes and preferences regarding CPR in a series of 18 questions. Fifty-one out of 67 (76.1%) patients completed the survey. Results indicated that 80.4% (n=41) of participants correctly understood the purpose of CPR, but 64.7% (n=33) did not know of any possible complications of CPR. Less than half (n=21, 41.2%) of participants had thought about life support measures they wanted for themselves. Most of the participants agreed that they should personally be involved in making end-of-life decisions (n=44, 86.3%). Many patients had a poor knowledge of CPR and other resuscitation measures and the majority overestimated the success rate of CPR. However, a majority were receptive to improving their knowledge and keen to discuss end-of-life issues with physicians. [ABSTRACT FROM AUTHOR]

We investigate the chaotic phase synchronization in a system of coupled bursting neurons in small-world networks. A transition to mutual phase synchronization takes place on the bursting time scale of coupled oscillators, while on the spiking time scale, they behave asynchronously. It is shown that phase synchronization is largely facilitated by a large fraction of shortcuts, but saturates when it exceeds a critical value. We also study the external chaotic phase synchronization of bursting oscillators in the small-world network by a periodic driving signal applied to a single neuron. It is demonstrated that there exists an optimal small-world topology, resulting in the largest peak value of frequency locking interval in the parameter plane, where bursting synchronization is maintained, even with the external driving. The width of this interval increases with the driving amplitude, but decrease rapidly with the network size. We infer that the externally applied driving parameters outside the frequency locking region can effectively suppress pathologically synchronized rhythms of bursting neurons in the brain. [ABSTRACT FROM AUTHOR]

A sensorless permanent-magnet synchronous motor (PMSM) drive is developed. A second-order Luenberger observer is used to estimate the position of the rotor flux and hence the rotor speed. The observer is computationally efficient as it has a simple structure and does not involve mechanical parameters. An integral-feedback method is adopted for the estimation of the rotor speed. The inner current loop is realised using a decoupling and diagonal internal model control algorithm. Details of the sensorless control system are given and the feasibility of the proposed method is verified through simulation and experiments. Satisfactory estimation accuracy is obtained even when the drive operates at very low speeds and also during rotor speed reversals. [ABSTRACT FROM AUTHOR]

In this paper, a method is proposed for offline signature verification. It is based on a smoothness criterion. It is observed that the cursive segments of forgery signatures are generally less smooth and less natural than the genuine ones, especially for those signatures that consist of cursive graphic patterns. Two approaches are proposed to extract a smoothness feature: a crossing method and a fractal dimension method. When the proposed smoothness feature is combined with other global shape features for signature verification, satisfactory results are obtained. [ABSTRACT FROM AUTHOR]

To determine the alterations of the p16/MTS1 gene in oral squamous cell carcinoma (OSCC), we examined in Taiwanese patients the mutation, deletion and methylation of p16/MTS1 in primary OSCCs associated mostly with betel quid (BQ)/tobacco use. Among 110 tumors undergoing mutational analyses, seven (6%) showed mutations in exon 2 or the intron 1/exon 2 splice site. All but one mutation disrupted the encoded proteins. Base transitions represented the vast majority (6/7) of the mutations identified in BQ/tobacco consuming subjects. It was noted that 15/56 (27%) tumors examined by restriction fragment methylation analysis revealed a significant level of methylation in different loci of exon 1 as compared with the respective non-cancerous tissue. Mutation of p16/MTS1 was exclusively identified in carcinomas of buccal mucosa, whereas methylation of the p16/MTS1 promoter region occurred preferentially in carcinomas of the tongue (54%) rather than at other sites (22%). Homozygous deletion was not found in 56 paired samples examined, nor was hemizygous deletion indicated in 12 informative cases. The results indicated aberrant methylation and mutation as the molecular abnormality of p16/MTS1 in the OSCC from Taiwanese. [ABSTRACT FROM AUTHOR]

The expression of p53 and p21WAF1 in 53 oral verrucous leukoplakias (OVLs), mostly non-dysplastic lesions, was investigated to ascertain the role of such events in malignant conversion. Immunohistochemical analysis revealed aberrant p53 and p21WAF1 immunoreactivity in 51% (27 cases) and 75% (40 cases), respectively. After an average follow-up period of three and a half years, histopathological examination revealed that 22 (42%) cases had developed oral squamous cell carcinoma (OSCC), 14 (26%) cases had undergone recurrence, and 17 (32%) cases were free of disease. The oncogenic potential of this subset of premalignant lesions warrants attention. A significant difference in the frequency of OSCC progression/recurrence was noted in lesions bearing aberrant immunoreactivity of either p53 (93% vs 42%; P=0.00008) or p21WAF1 (80% vs 32%; P=0.002) in comparison with lesions without immunoreactivity. This study suggested that the aberrant immunoreactivity of p53 and p21WAF1 may represent important alterations of OVL and could affect the outcome of this lesion. [ABSTRACT FROM AUTHOR]

To investigate the role of telomerase in oral carcinogenesis, we assayed telomerase activity in various oral tissues by a modified telomeric repeat amplification protocol (TRAP) analysis. Also, using digoxigenin-labeled probes, we measured the in situ expression of human telomerase RNA component (hTR) in paired oral squamous cell carcinomas (OSCC) and adjacent non-cancerous matched tissue (NCMT). We detected telomerase activity in three OSCC cell lines, but not in primary oral keratinocytes. In patient samples, most OSCC (36/42, 86%) and oral premalignant lesions (8/12, 67%) possessed telomerase activity. In addition, 6 of 27 (22%) NCMT contained weak telomerase activity. In situ hybridization showed that hTR was expressed in almost all OSCC (23/27, 85%) as well as in the majority of NCMT (20/25, 80%). In most cases, accumulation of hTR was observed both in the nucleus and cytoplasm of epithelial cells. A correlation between hTR expression and more advanced tumor grade was observed. The appearance of telomerase activation and hTR expression during oral carcinogenesis was different. This study indicates that the activation of telomerase is an early and frequent event in OSCC. [ABSTRACT FROM AUTHOR]

Alterations of p53 have been explored in Taiwanese oral squamous cell carcinomas (OSCCs) consisting of a betel quid (BQ)/tobacco-related subgroup of 36 subjects and a tobacco-related subgroup of 13 subjects. Mutations in conserved exons were found in 12 tumors. Seven mutations were clustered in a hot-spot region mapped to a region between codons 273-282 in exon 8. The incidence of p53 mutation in BQ/tobacco tumors was 22% (8/36), The frequency of p53 allelic loss (21%, 3/41) in BQ/tobacco tumors approximates to the incidence of mutation. This is the first study demonstrating allelic deletion of p53 in such malignancies. Twenty-four of 43 samples showed positive p53 immunostaining. All tumors harboring mis-sense mutations of p53 in conserved exons exhibited nuclear protein accumulation. The incidence of imitation in conserved exons in BQ/tobacco-associated Asian OSCCs (15%) is significantly different from worldwide OSCCs (46%) related primarily to tobacco consumption (P=0.0000l). [ABSTRACT FROM AUTHOR]