Prespecified dose-response analysis for A Very Early Rehabilitation Trial (AVERT)

OBJECTIVE:
Our prespecified dose-response analyses of A Very Early Rehabilitation Trial (AVERT) aim to provide practical guidance for clinicians on the timing, frequency, and amount of mobilization following acute stroke.

METHODS:
Eligible patients were aged ≥18 years, had confirmed first (or recurrent) stroke, and were admitted to a stroke unit within 24 hours of stroke onset. Patients were randomized to receive very early and frequent mobilization, commencing within 24 hours, or usual care. We used regression analyses and Classification and Regression Trees (CART) to investigate the effect of timing and dose of mobilization on efficacy and safety outcomes, irrespective of assigned treatment group.

RESULTS:
A total of 2,104 patients were enrolled, of whom 2,083 (99.0%) were followed up at 3 months. We found a consistent pattern of improved odds of favorable outcome in efficacy and safety outcomes with increased daily frequency of out-of-bed sessions (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.09 to 1.18, p < 0.001), keeping time to first mobilization and mobilization amount constant. Increased amount (minutes per day) of mobilization reduced the odds of a good outcome (OR 0.94, 95% CI 0.91 to 0.97, p < 0.001). Session frequency was the most important variable in the CART analysis, after prognostic variables age and baseline stroke severity.

CONCLUSION:
These data suggest that shorter, more frequent mobilization early after acute stroke is associated with greater odds of favorable outcome at 3 months when controlling for age and stroke severity.

CLASSIFICATION OF EVIDENCE:
This study provides Class III evidence that shorter, more frequent early mobilization improves the chance of regaining independence after stroke.

Stability analysis of a general family of nonlinear positive discrete time-delay systems

In this paper, we propose a new approach to analyse the stability of a general family of nonlinear positive discrete time-delay systems. First, we introduce a new class of nonlinear positive discrete time-delay systems, which generalises some existing discrete time-delay systems. Second, through a new technique that relies on the comparison and mathematical induction method, we establish explicit criteria for stability and instability of the systems. Three numerical examples are given to illustrate the feasibility of the obtained results.

Additional weekend therapy may reduce length of rehabilitation stay after stroke: a meta-analysis of individual patient data

QUESTIONS: Among people receiving inpatient rehabilitation after stroke, does additional weekend physiotherapy and/or occupational therapy reduce the length of rehabilitation hospital stay compared to those who receive a weekday-only service, and does this change after controlling for individual factors? Does additional weekend therapy improve the ability to walk and perform activities of daily living, measured at discharge? Does additional weekend therapy improve health-related quality of life, measured 6 months after discharge from rehabilitation? Which individual, clinical and hospital characteristics are associated with shorter length of rehabilitation hospital stay? DESIGN: This study pooled individual data from two randomised, controlled trials (n=350) using an individual patient data meta-analysis and multivariate regression. PARTICIPANTS: People with stroke admitted to inpatient rehabilitation facilities. INTERVENTION: Additional weekend therapy (physiotherapy and/or occupational therapy) compared to usual care (5 days/week therapy). OUTCOME MEASURES: Length of rehabilitation hospital stay, independence in activities of daily living measured with the Functional Independence Measure, walking speed and health-related quality of life. RESULTS: Participants who received weekend therapy had a shorter length of rehabilitation hospital stay. In the un-adjusted analysis, this was not statistically significant (MD -5.7 days, 95% CI -13.0 to 1.5). Controlling for hospital site, age, walking speed and Functional Independence Measure score on admission, receiving weekend therapy was significantly associated with a shorter length of rehabilitation hospital stay (β=7.5, 95% CI 1.7 to 13.4, p=0.001). There were no significant between-group differences in Functional Independence Measure scores (MD 1.9 points, 95% CI -2.8 to 6.6), walking speed (MD 0.06 m/second, 95% CI -0.15 to 0.04) or health-related quality of life (SMD -0.04, 95% CI -0.26 to 0.19) at discharge. DISCUSSION: Modest evidence indicates that additional weekend therapy might reduce rehabilitation hospital length of stay.

On the proximal Landweber Newton method for a class of nonsmooth convex problems

We consider a class of nonsmooth convex optimization problems where the objective function is a convex differentiable function regularized by the sum of the group reproducing kernel norm and (Formula presented.)-norm of the problem variables. This class of problems has many applications in variable selections such as the group LASSO and sparse group LASSO. In this paper, we propose a proximal Landweber Newton method for this class of convex optimization problems, and carry out the convergence and computational complexity analysis for this method. Theoretical analysis and numerical results show that the proposed algorithm is promising.

Distribution entropy analysis of epileptic EEG signals

It is an open-ended challenge to accurately detect the epileptic seizures through electroencephalogram (EEG) signals. Recently published studies have made elaborate attempts to distinguish between the normal and epileptic EEG signals by advanced nonlinear entropy methods, such as the approximate entropy, sample entropy, fuzzy entropy, and permutation entropy, etc. Most recently, a novel distribution entropy (DistEn) has been reported to have superior performance compared with the conventional entropy methods for especially short length data. We thus aimed, in the present study, to show the potential of DistEn in the analysis of epileptic EEG signals. The publicly-accessible Bonn database which consisted of normal, interictal, and ictal EEG signals was used in this study. Three different measurement protocols were set for better understanding the performance of DistEn, which are: i) calculate the DistEn of a specific EEG signal using the full recording; ii) calculate the DistEn by averaging the results for all its possible non-overlapped 5 second segments; and iii) calculate it by averaging the DistEn values for all the possible non-overlapped segments of 1 second length, respectively. Results for all three protocols indicated a statistically significantly increased DistEn for the ictal class compared with both the normal and interictal classes. Besides, the results obtained under the third protocol, which only used very short segments (1 s) of EEG recordings showed a significantly (p <; 0.05) increased DistEn for the interictal class in compassion with the normal class, whereas both analyses using relatively long EEG signals failed in tracking this difference between them, which may be due to a nonstationarity effect on entropy algorithm. The capability of discriminating between the normal and interictal EEG signals is of great clinical relevance since it may provide helpful tools for the detection of a seizure onset. Therefore, our study suggests that the DistEn analysis of EEG signals is very promising for clinical and even portable EEG monitoring.

ANALYSIS OF GENDER RELATIONS IN THE INDUSTRIAL COMMUNITY OF AGUIRRE, PUERTO RICO

This thesis is a study of the gender relations of the residents of Aguirre, Puerto Rico, between 1940 and 1991. The primary goal of the project was to explore how gender roles and relations in the Aguirre community were impacted by the social class system introduced by the Aguirre Sugar Company. This project was based on the interpretation of the past and present situation of the Aguirre community using oral history, by conducting a series of interviews among its residents. The interviews resulted in three main themes. First, the concepts of `normal and natural' were used to distinguish gender roles. Second, Aguirreños identified `family as community', since through the family individuals built their gender identity and learned the basic rules of coexistence within the social hierarchy of the community. Third, although the gender and class roles were clear in the community, `resistance and negotiation' occurred in the home and at the Company between those of different gender and social classes. The Aguirre Sugar Company was one of the principal influences on the construction of the Aguirreños identity, and left a mark on the past, present and future generations.

On and off the stage at Atlanta Greek Picnic: Performances of collective black middle-class identities and the politics of belonging

This dissertation presents a thick ethnography that engages in the micro-analysis of the situationality of black middle-class collective identification processes through an examination of performances by members of the nine historically black sororities and fraternities at Atlanta Greek Picnic, an annual festival that occurs at the beginning of June in Atlanta, Georgia. It mainly attracts undergraduate and graduate members of these university-based organizations, as they exist all over the United States. This exploration of black Greek-letter organization (BGLO) performances uncovers processes through which young black middle-class individuals attempt to combine two universes that are at first glance in complete opposition to each other: the domain of the traditional black middle-class values with representations and fashions stemming from black popular culture. These constructions also attempt to incorporate—in a contradiction of sorts— black popular cultural elements in the objective to deconstruct the social conservatism that characterizes middle-class values, particularly in relation to sexuality and its representation in social behaviors and performances. This negotiation between prescribed v middle-class values of respectability and black popular culture provides a space wherein black individuals challenge and/or perpetuate those dominant tropes through identity performances that feed into the formation of black sexual politics, which I examine through a variety of BGLO staged and non-staged performances. ^

A real time electromagnetic analysis of electric machines for educational purposes and laboratory implementation

This thesis presents a system for visually analyzing the electromagnetic fields of the electrical machines in the energy conversion laboratory. The system basically utilizes the finite element method to achieve a real-time effect in the analysis of electrical machines during hands-on experimentation. The system developed is a tool to support the student's understanding of the electromagnetic field by calculating performance measures and operational concepts pertaining to the practical study of electrical machines. Energy conversion courses are fundamental in electrical engineering. The laboratory is conducted oriented to facilitate the practical application of the theory presented in class, enabling the student to use electromagnetic field solutions obtained numerically to calculate performance measures and operating characteristics. Laboratory experiments are utilized to help the students understand the electromagnetic concepts by the use of this visual and interactive analysis system. In this system, this understanding is accomplished while hands-on experimentation takes place in real-time.

Exploring Hidden Coherent Feature Groups and Temporal Semantics for Multimedia Big Data Analysis

Thanks to the advanced technologies and social networks that allow the data to be widely shared among the Internet, there is an explosion of pervasive multimedia data, generating high demands of multimedia services and applications in various areas for people to easily access and manage multimedia data. Towards such demands, multimedia big data analysis has become an emerging hot topic in both industry and academia, which ranges from basic infrastructure, management, search, and mining to security, privacy, and applications. Within the scope of this dissertation, a multimedia big data analysis framework is proposed for semantic information management and retrieval with a focus on rare event detection in videos. The proposed framework is able to explore hidden semantic feature groups in multimedia data and incorporate temporal semantics, especially for video event detection. First, a hierarchical semantic data representation is presented to alleviate the semantic gap issue, and the Hidden Coherent Feature Group (HCFG) analysis method is proposed to capture the correlation between features and separate the original feature set into semantic groups, seamlessly integrating multimedia data in multiple modalities. Next, an Importance Factor based Temporal Multiple Correspondence Analysis (i.e., IF-TMCA) approach is presented for effective event detection. Specifically, the HCFG algorithm is integrated with the Hierarchical Information Gain Analysis (HIGA) method to generate the Importance Factor (IF) for producing the initial detection results. Then, the TMCA algorithm is proposed to efficiently incorporate temporal semantics for re-ranking and improving the final performance. At last, a sampling-based ensemble learning mechanism is applied to further accommodate the imbalanced datasets. In addition to the multimedia semantic representation and class imbalance problems, lack of organization is another critical issue for multimedia big data analysis. In this framework, an affinity propagation-based summarization method is also proposed to transform the unorganized data into a better structure with clean and well-organized information. The whole framework has been thoroughly evaluated across multiple domains, such as soccer goal event detection and disaster information management.

High Frequency Class DE Converter Using a Multilayer Coreless PCB Transformer

In modern power electronics equipment, it is desirable to design a low profile, high power density, and fast dynamic response converter. Increases in switching frequency reduce the size of the passive components such as transformers, inductors, and capacitors which results in compact size and less requirement for the energy storage. In addition, the fast dynamic response can be achieved by operating at high frequency. However, achieving high frequency operation while keeping the efficiency high, requires new advanced devices, higher performance magnetic components, and new circuit topology. These are required to absorb and utilize the parasitic components and also to mitigate the frequency dependent losses including switching loss, gating loss, and magnetic loss. Required performance improvements can be achieved through the use of Radio Frequency (RF) design techniques. To reduce switching losses, resonant converter topologies like resonant RF amplifiers (inverters) combined with a rectifier are the effective solution to maintain high efficiency at high switching frequencies through using the techniques such as device parasitic absorption, Zero Voltage Switching (ZVS), Zero Current Switching (ZCS), and a resonant gating. Gallium Nitride (GaN) device technologies are being broadly used in RF amplifiers due to their lower on- resistance and device capacitances compared with silicon (Si) devices. Therefore, this kind of semiconductor is well suited for high frequency power converters. The major problems involved with high frequency magnetics are skin and proximity effects, increased core and copper losses, unbalanced magnetic flux distribution generating localized hot spots, and reduced coupling coefficient. In order to eliminate the magnetic core losses which play a crucial role at higher operating frequencies, a coreless PCB transformer can be used. Compared to the conventional wire-wound transformer, a planar PCB transformer in which the windings are laid on the Printed Board Circuit (PCB) has a low profile structure, excellent thermal characteristics, and ease of manufacturing. Therefore, the work in this thesis demonstrates the design and analysis of an isolated low profile class DE resonant converter operating at 10 MHz switching frequency with a nominal output of 150 W. The power stage consists of a class DE inverter using GaN devices along with a sinusoidal gate drive circuit on the primary side and a class DE rectifier on the secondary side. For obtaining the stringent height converter, isolation is provided by a 10-layered coreless PCB transformer of 1:20 turn’s ratio. It is designed and optimized using 3D Finite Element Method (FEM) tools and radio frequency (RF) circuit design software. Simulation and experimental results are presented for a 10-layered coreless PCB transformer operating in 10 MHz.

Work, class and conflict: a comparative study of three Cork factories, incorporating oral testimony

This dissertation presents a comparative study of three factories in Cork Harbour area, Sunbeam Wolsey (1927-90), Irish Steel (1939-2001) and the Ford Marina Plant (1917-84). All three factories were significant industrial employers in both a domestic (Irish) and a local (Cork) context and are broadly representative of the Irish manufacturing industry that was developed under the policies of tariff protection introduced in the 1930s and gradually phased out between the late 1950s and the mid-1980s. Sunbeam Wolsey was a textile and clothing concern located on the north side of Cork City that possessed a borderline monopoly within its economic sector and was among the largest private employers of female labour in twentieth century Ireland. Irish Steel was the country’s only steel mill, located on Haulbowline island, a brief ferry-ride from the seaside town of Cobh, and was unusual in being one of the few manufacturing concerns operated as a nationalised industry under the auspices of the state. The Ford Marina plant predated the introduction of protectionism by more than a decade and began as the centre of the Ford empire’s tractor manufacturing business, before switching to the production of private motor vehicles for the Irish market in 1932. All three industries were closed or sold off when the state withdrew support, either in the form of tariff protection (Ford, Sunbeam) or direct funding (Irish Steel). While devoting much attention to the three firms, the central concern of this dissertation is not the companies themselves (though the economic history portion of the dissertation is substantial), but the workers they employed, examining the lives of these individuals both as members of the Irish working class, and, more specifically, as employees of the three factories under consideration. The project can be best described as a comparative factory study, comparing and contrasting the three workforces, focusing primarily on industrial relation and the experience of work. This dissertation utilises both documentary evidence and a significant quantity of oral testimony, breaking new ground by making the workplace the central focus of its investigation. The principal aims of the study are: 1. To document the lives of those who worked in these factories, capturing through oral testimony their subjective experiences of social class and factory life, as well as differences among narrators in terms of gender and status. In achieving this aim, the study will provide a broader social context for its detailed analysis of work and industrial relations in each firm. 2. To analyse the three workplaces and determine how and why each developed such distinct systems of industrial relations at the factory level, as well as to compare and contrast these systems. 3. To examine the nature of work in each factory and to determine how work and industrial relations in each firm developed over time, relating these changes both to internal and external factors. Additionally, the project will provide a comparative analysis of these changes.

Field ‘work’ vs ‘feel’ trip : approaches to out-of-class experiences in geography education

Fieldwork is viewed as integral to geography teaching and acclaimed benefits often include holistic, student-driven learning, where all the senses are engaged and the impacts are more than cognitive. While these benefits are often assumed, in this paper, I argue that geography fieldwork in schools is often teacher-led and focused on the intellectual task of knowledge acquisition and skill development. Based on a qualitative content analysis of examples of fieldwork in a state geography teachers’ journal, I assert that the affective and sensory dimensions, are often used to promote the benefits of fieldwork, but seldom explicitly addressed through fieldwork pedagogy and learning activities in school geography. I contend that this is a missed opportunity for a deeper, more embodied and critical engagement with, and response to, the places visited.

Gender, class and the household economy in Scotland in the ‘Age of affluence’

From early 1950s to the early 1970s Britain is said to have experienced an ‘age of affluence’. Whilst material conditions for many households improved in these decades, this detailed examination of budget management processes shows that for many working-class households, these gains were the product of hard work and careful money management. Using oral history methodology, this thesis explores lived experiences of the household economy to illuminate these qualifications to ‘affluence’. In so doing, this thesis advances analysis which considers the relationship between the macro-level economic conditions of affluence and the everyday economic realities of households in the post-war period. The thesis examines the operation of the household economy and shows how working-class households utilised domestic labour, budgeting, paid work, credit and thrift to make ends meet, as well as to achieve ‘affluence’. Further, by exploring these areas of the household economy, this thesis shows that gendered ideology continued to preserve power and material inequalities between men and women. Although considerable change did occur, particularly involvement in the paid labour market, domestic responsibilities continued to be an important focus of women’s identities and the effective performance of these duties by women remained central to the success of the household. This thesis represents a fresh focus on how the exploration of everyday life, including the salience of ideological continuities in shaping experience, can qualify and refine our understanding of twentieth century economic and social change, and contributes to socio-historical understandings of ‘affluence’ and its intersections with the household, gender, and class.

A new approach for computing a flood vulnerability index using cluster analysis

A Flood Vulnerability Index (FloodVI) was developed using Principal Component Analysis (PCA) and a new aggregation method based on Cluster Analysis (CA). PCA simplifies a large number of variables into a few uncorrelated factors representing the social, economic, physical and environmental dimensions of vulnerability. CA groups areas that have the same characteristics in terms of vulnerability into vulnerability classes. The grouping of the areas determines their classification contrary to other aggregation methods in which the areas' classification determines their grouping. While other aggregation methods distribute the areas into classes, in an artificial manner, by imposing a certain probability for an area to belong to a certain class, as determined by the assumption that the aggregation measure used is normally distributed, CA does not constrain the distribution of the areas by the classes. FloodVI was designed at the neighbourhood level and was applied to the Portuguese municipality of Vila Nova de Gaia where several flood events have taken place in the recent past. The FloodVI sensitivity was assessed using three different aggregation methods: the sum of component scores, the first component score and the weighted sum of component scores. The results highlight the sensitivity of the FloodVI to different aggregation methods. Both sum of component scores and weighted sum of component scores have shown similar results. The first component score aggregation method classifies almost all areas as having medium vulnerability and finally the results obtained using the CA show a distinct differentiation of the vulnerability where hot spots can be clearly identified. The information provided by records of previous flood events corroborate the results obtained with CA, because the inundated areas with greater damages are those that are identified as high and very high vulnerability areas by CA. This supports the fact that CA provides a reliable FloodVI.

Raman microscopy of formamide-intercalated kaolinites treated by controlled-rate thermal analysis technology

Raman spectroscopy of formamide-intercalated kaolinites treated using controlled-rate thermal analysis technology (CRTA), allowing the separation of adsorbed formamide from intercalated formamide in formamide-intercalated kaolinites, is reported. The Raman spectra of the CRTA-treated formamide-intercalated kaolinites are significantly different from those of the intercalated kaolinites, which display a combination of both intercalated and adsorbed formamide. An intense band is observed at 3629 cm-1, attributed to the inner surface hydroxyls hydrogen bonded to the formamide. Broad bands are observed at 3600 and 3639 cm-1, assigned to the inner surface hydroxyls, which are hydrogen bonded to the adsorbed water molecules. The hydroxyl-stretching band of the inner hydroxyl is observed at 3621 cm-1 in the Raman spectra of the CRTA-treated formamide-intercalated kaolinites. The results of thermal analysis show that the amount of intercalated formamide between the kaolinite layers is independent of the presence of water. Significant differences are observed in the CO stretching region between the adsorbed and intercalated formamide.