593 research outputs found
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A coupled rotor-fuselage aeroelastic analysis using complex rotor modes
A new modal method capable of analysing the aeroelastic response of rotorcraft in both steady and manoeuvring flight is developed. Particular emphasis is given to the correct modelling of the dynamic interactions between the rotor and the fuselage. This is achieved via the use of complex rotor modes, which allows the effects of hub motion to be incorporated. The modal Lagrangian equation for a single rotating blade using real modes as state variables is first derived. The important non-linear terms based on an ordering scheme are retained. This aeroelastic model is then extended to adopt the complex rotor modes as state variables. This concept, which is both new and analytically demanding, is furnished with minimum algebra. A generalised proof of complex modes orthogonality and its application to the coupled rotor-fuselage dynamic system are provided. Important conclusions drawn from this proof include: A set of complex left-hand eigenvectors are required, together with the right-hand set, in order to reduce the system response equations to an uncoupled modal form suitable for a solution; and It is necessary for the modes analysis to be re-formulated as an eigenvalue problem replacing the transfer matrix solution procedure. An orthogonalisation procedure is employed to reduce the complex system response equations to the uncoupled modal form. The procedure not only simplifies the algebraic process, but also identifies exactly the forcing functions present in the dynamic system modelled. However, for consistency wi th the dynamic model, it is necessary to restrict the blade model to a straight beam with small pre-deformed angles. The need to treat both the complex coupled and reactionless mode sets simultaneously, when they are defined in different reference frames, requires special attention to the solution of the modal responses. A numerical technique is developed for filtering the applied forces and hence identifying the forcing for the respective mode types. The fundamental issue regarding the true definition of angle of attack used for aerodynamic calculation is also addressed. The second order pseudo-torsion term must be removed from the incidence expression to ensure the aerodynamic loads are calculated correctly. The determination of the blade structural loads using both Modal Summation and Force Integration methods is discussed and described. A novel numerical technique, based on curve fitting using Chebyshev polynomials coupled with analytical integration, is devised and shown for the first time to minimise the inherent numerical problems associated with Force Integration. Finally, applications of the analytical model to include the effects of hub motion on vibratory loads calculation and to determine loads in an extreme manoeuvre are successfully demonstrated. The use of rotor modes by including transmission flexibility in a rotor dynamic model in loads calculation is also provided. These correlations establish the important milestone on the ability of this model to improve vibration prediction and to simulate manoeuvring flight. They also demonstrate the potential applications of this model. Recommendations for future
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The role of social media data in operations and production management
Social media data contain rich information in posts or comments written by customers. If those data can be extracted and analysed properly, companies can fully utilise this rich source of information. They can then convert the data to useful information or knowledge, which can help to formulate their business strategy. This cannot only facilitate marketing research in view of customer behaviour, but can also aid other management disciplines. Operations management (OM) research and practice with the objective to make decisions on product and process design is a fine example. Nevertheless, this line of thought is under-researched. In this connection, this paper explores the role of social media data in OM research. A structured approach is proposed, which involves the analysis of social media comments and a statistical cluster analysis to identify the interrelationships amongst important factors. A real-life example is employed to demonstrate the concept
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Demystifying case management in Aotearoa New Zealand: A scoping and mapping review
YesBackground: Community-based case managers in health have been compared to glue which holds the dynamic needs of clients to a disjointed range of health and social services. However, case manager roles are difficult to understand due to poorly defined roles, confusing terminology, and low visibility in New Zealand. Aim: This review aims to map the landscape of case management work to advance workforce planning by clarifying the jobs, roles, and relationships of case managers in Aotearoa New Zealand (NZ). Methods: Our scoping and mapping review includes peer-reviewed articles, grey literature sources, and interview data from 15 case managers. Data was charted iteratively until convergent patterns emerged and distinctive roles identified. Results: A rich and diverse body of literature describing and evaluating case management work in NZ (n = 148) is uncovered with at least 38 different job titles recorded. 18 distinctive roles are further analyzed with sufficient data to explore the research question. Social ecology maps highlight diverse interprofessional and intersectoral relationships. Conclusions: Significant innovation and adaptations are evident in this field, particularly in the last five years. Case managers also known as health navigators, play a pivotal but often undervalued role in NZ health care, through their interprofessional and intersectoral relationships. Their work is often unrecognised which impedes workforce development and the promotion of person-centered and integrated health care.This research was funded by the AUT University, Faculty of Health & Environmental Sciences Summer Student Grant 2021/2022 and the School of Public Health and Interdisciplinary Studies PBRF Funding 2021. The APC charge is covered by the School of Public Health and Interdisciplinary Studies PBRF 2022
Angiotensin-converting enzyme (ACE) inhibition in type 2, diabetic patients – interaction with ACE insertion/deletion polymorphism
Angiotensin-converting enzyme (ACE) insertion(I)/deletion (D) polymorphism may modify the effect of inhibition of the renin–angiotensin–aldosterone system (RAAS) on survival and cardiorenal outcomes in type 2, diabetes. A consecutive cohort of 2089 Chinese type 2 diabetic patients with mean (±standard deviation) age of 59.7±13.1 years were genotyped for this polymorphism by polymerase chain reaction method and were followed prospectively for a median period of 44.6 (interquartile range: 23.7, 57.5) months. Clinical outcomes, including all-cause mortality, cardiovascular and renal end points, were examined. The frequency for I allele was 67.1 and 32.9% for D allele, with observed genotype frequencies of 45.8, 42.6, and 11.6% for 3, DI and DD, respectively. ACE DD polymorphism was an independent predictor for renal end point with hazard ratio (HR) (95% confidence interval) of 1.72 (1.16, 2.56), but not for cardiovascular end point or mortality. After controlling for confounding factors, including ACE I/D genotype, the usage of RAAS inhibitors was associated with reduced risk of mortality (HR 0.34 (0.23, 0.50)) and renal end point (HR 0.55 (0.40, 0.75)). On subgroup analysis, the beneficial effects on survival (II vs DI vs DD: HR 0.29 (0.16, 0.51) vs 0.25 (0.14, 0.46) vs 1.33 (0.41, 4.31)) and renoprotection (II vs DI vs DD: 0.52 (0.30, 0.90) vs 0.43 (0.25, 0.72) vs 0.95 (0.43, 2.12)) were most evident in II and DI carriers. In conclusion, inhibition of RAAS was associated with reduced risk of mortality and occurrence of renal end point in Chinese type 2 diabetic patients. These benefits were most evident among II and DI carriers
Image-Guided Ablative Therapies for Lung Tumors
While the gold standard for early stage lung cancers is still surgical resection, many patients have comorbidities or suboptimal lung function making surgery unfavorable. At the same time, more and more small lung nodules are being incidentally discovered on computer tomography (CT), leading to the discovery of pre-malignant or very early stage lung cancers without regional spread, which could probably be eradicated without anatomical surgical resection. Various ablative energies and technologies are available on the market, including radiofrequency ablation, microwave ablation, cryoablation, and less commonly laser ablation and irreversible electroporation. For each technology, the mechanism of action, advantages, limitations, potential complications and evidence-based outcomes will be reviewed. Traditionally, these ablative therapies were done under CT guidance with percutaneous insertion of ablative probes. Recently, bronchoscopic ablation under ultrasound, CT, or electromagnetic navigation bronchoscopy guidance is gaining popularity due to improved navigation precision, reduced pleural-based complications, and providing a true “wound-less” option
Global Incidence and mortality of oesophageal cancer and their correlation with socioeconomic indicators temporal patterns and trends in 41 countries
Oesophageal cancers (adenocarcinomas [AC] and squamous cell carcinomas [SCC]) are characterized by high incidence/mortality in many countries. We aimed to delineate its global incidence and mortality, and studied whether socioeconomic development and its incidence rate were correlated. The age-standardized rates (ASRs) of incidence and mortality of this medical condition in 2012 for 184 nations from the GLOBOCAN database; national databases capturing incidence rates, and the WHO mortality database were examined. Their correlations with two indicators of socioeconomic development were evaluated. Joinpoint regression analysis was used to generate trends. The ratio between the ASR of AC and SCC was strongly correlated with HDI (r = 0.535 [men]; r = 0.661 [women]) and GDP (r = 0.594 [men]; r = 0.550 [women], both p < 0.001). Countries that reported the largest reduction in incidence in male included Poland (Average Annual Percent Change [AAPC] = −7.1, 95%C.I. = −12,−1.9) and Singapore (AAPC = −5.8, 95%C.I. = −9.5,−1.9), whereas for women the greatest decline was seen in Singapore (AAPC = −12.3, 95%C.I. = −17.3,−6.9) and China (AAPC = −5.6, 95%C.I. = −7.6,−3.4). The Philippines (AAPC = 4.3, 95%C.I. = 2,6.6) and Bulgaria (AAPC = 2.8, 95%C.I. = 0.5,5.1) had a significant mortality increase in men; whilst Columbia (AAPC = −6.1, 95%C.I. = −7.5,−4.6) and Slovenia (AAPC = −4.6, 95%C.I. = −7.9,−1.3) reported mortality decline in women. These findings inform individuals at increased risk for primary prevention
The Role of Translation Initiation Regulation in Haematopoiesis
Organisation of RNAs into functional subgroups that are translated in response to extrinsic and intrinsic factors underlines a relatively unexplored gene expression modulation that drives cell fate in the same manner as regulation of the transcriptome by transcription factors. Recent studies on the molecular mechanisms of inflammatory responses and haematological disorders indicate clearly that the regulation of mRNA translation at the level of translation initiation, mRNA stability, and protein isoform synthesis is implicated in the tight regulation of gene expression. This paper outlines how these posttranscriptional control mechanisms, including control at the level of translation initiation factors and the role of RNA binding proteins, affect hematopoiesis. The clinical relevance of these mechanisms in haematological disorders indicates clearly the potential therapeutic implications and the need of molecular tools that allow measurement at the level of translational control. Although the importance of miRNAs in translation control is well recognised and studied extensively, this paper will exclude detailed account of this level of control
Soothing dementia carers: a pilot evaluation of an imagery-based wellbeing app feature to support family carers of people with dementia during the COVID-19 pandemic
Background:
The COVID-19 pandemic has presented unprecedented risks to the health of people living with dementia. Confinement to their homes and extra pressure on the health and social care system, left people with dementia and their carers with reduced access to care services. Accordingly, family carers assumed more caring responsibilities and faced a greater risk of social isolation and loneliness, negatively affecting their mental wellbeing. In response, we developed a new imagery-based feature called Project Soothe within an existing app, CogniCare, which aimed to support the wellbeing of family carers looking after someone with dementia at home.
Methods:
This new feature aimed to test the utility of our previous research which has shown that viewing soothing images has positive mood benefits on users. In this pilot, we examined the usage of the Project Soothe feature over a one-year period.
Results:
Our results indicate the feasibility of the imagery-based app feature as we found that most users found viewing the soothing images to have a positive influence on their mood.
Conclusions:
This finding illustrates feasibility of this imagery-based wellbeing app in this population of interest, and suggests that, upon further replication and research, the Project Soothe feature within the CogniCare app has potential to be developed as a digital wellbeing tool for family carers of people with dementia
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