bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors differentially associated with early readmission at a university teaching psychiatric hospital
Authors: Hamilton Jane E. , Rhoades Howard , Galvez Juan , Allen Melissa , Green Charles , Aller Mildred , Soares Jair C.
Published: March 2015

Rationale, aims and objectives

The rate of psychiatric readmissions within 30 days of discharge is a well‐established behavioural health system performance measure linked to the quality of inpatient hospital care as well as to access to community‐based aftercare services. The purpose of this study was to examine the factors differentially associated with earlier readmission among a sample of patients (n = 588) readmitted within 30 days of discharge to a university teaching psychiatric hospital from 2001 to 2010.

Methods

Quality assurance interviews were conducted with patients readmitted within 30 days of discharge. The interview data were merged with clinical symptom and electronic medical record data. Multinomial logistic regression analysis was used to examine readmission within 7 days and from 8 to 14 days compared with 15–30 days after discharge while controlling for socio‐demographic and treatment variables previously associated with psychiatric readmission.

Results

Multiple clinical, treatment and patient‐reported factors were differentially associated with earlier readmission. In particular, lack of engagement in post‐discharge aftercare services was a strong predictor of earlier readmission.

Conclusions

Strategies are needed to improve patients' transition from inpatient psychiatric hospitalization to aftercare services. Psychiatric hospitals attempting to reduce very early readmissions should seek to implement innovative transitional care initiatives targeting both patient and treatment factors.
The development, implementation and evaluation of clinical practice guidelines in Gulf Cooperation Council (GCC) countries: a systematic review of literature
Authors: Koornneef Erik , Robben Paul , Hajat Cother , Ali Azhar
Published: March 2015

Rationale, aims and objectives

Our aim was to examine and describe the current situation in Gulf Cooperation Council (GCC) member countries regarding the development, implementation and evaluation of clinical practice guidelines (CPG). The objectives were to describe from where the studies originated, what the clinical focus was of each study and examine the methodology and the status of each study (i.e. development, dissemination, implementation and evaluation).

Methods

Review of literature – two stages: stage 1: screening through an abstract review, followed by independent adjudicator; stage 2: detailed assessment and classification.

Results

Considering the widespread acceptance that CPG's are useful and effective tools for quality improvement in health care, it is worth noting that relatively few studies have been conducted in the GCC region that examine CPG. Furthermore, the reviewers found that the quality of the research methods used could be improved. The majority of the studies that were conducted evaluated the effects of guidelines and focused on the ‘lifestyle diseases’, in particular diabetes and cardiovascular diseases. It is also worth noting that there has been a steady increase in the number of publications over the 10 years period.

Conclusions

More attention needs to be given to developing, disseminating, implementing and evaluating CPG's in the GCC region in order to improve the quality and safety of health care.
Impact of Combination Treatments of Modified Atmosphere Packaging and Refrigeration on the Status of Antioxidants in Highly Perishable Strawberries
Authors: Bhat Rajeev , Stamminger Rainer
Published: March 2015

Strawberry fruits are highly appreciated for their distinctive aroma, mouthfeel and exceptional organoleptic properties. However, owing to their perishable nature, preservation and extension of shelf life of strawberries has been a major challenge. In this study, for the first time, combination effects of modified atmosphere packaging (combination of N2 and CO2 with 1% O2) and refrigeration (0, 5 and 10C, with 25C as control) on antioxidant activity and level of antioxidant compounds were evaluated. Encouraging results were obtained, which were all depended on the packaging, temperature used and storage days.

Practical Applications

The present research work is expected to add database to the existing knowledge on various challenges incurred for safe preservation and shelf life extension of strawberries. Depending on the requirements, it is envisaged that the information generated in this study will be of practical help to comprehend the effectiveness of employing combination treatments of modified atmosphere packaging and cold storage treatments on handling freshly harvested strawberries and can be explored commercially for preservation purposes, provided more standardization is undertaken.
Effect of Vibration on the Quality of Strawberry Fruits Caused by Simulated Transport
Authors: La Scalia G. , Aiello G. , Miceli A. , Nasca A. , Alfonzo A. , Settanni L.
Published: March 2015

Mechanical damage of agricultural products is one of the main problems in the harvest and postharvest chain due to the large economic loss that the shelf life reduction could generate. Measurements of change in the chemical components of highly perishable products and microbial growth under different static and dynamic loads is the first step in the development of intelligent logistic units that could help in predicting the residual shelf life in order to minimize losses along the supply chain. In our research, the effects of vibration along the supply chain of a case study were analyzed on strawberry (Fragaria × ananassa) and woodland strawberry (Fragaria vesca) in terms of microbiological and quality assessment. Fruits were subjected to vibration in a temperature‐controlled environment, simulating the transport conditions. Microbiological and quality analyses were conducted in three different positions along the column of the crates. The results were compared with the nonvibrated strawberries stored in the same environmental conditions along the whole cold chain, showing that vibrations cause a significant decrease in the qualitative characteristics of both fruits.

Practical Applications

The practical application obtainable from our research is the development of ad hoc economically affordable sensors based on the volatile organic compounds (VOCs) emitted by the microorganisms showing the most rapid increase. The measurement of the VOCs of the dominant microorganisms could be implemented in a smart logistic unit as it provides information on the microbial evolution in real time. The research proposed configures as a first step to achieve such objective, and toward the development of a supply chain monitoring and control infrastructure relaying on the correlation of vibration phenomena with the VOCs originated by the microbiological activity. The methodology consists of measuring the effects of vibration along a reference supply chain in terms of microbiological and quality assessment, with the aim of extrapolating a mathematical correlation that can further be generalized into a replicable model.
New simple prognostic score for primary biliary cirrhosis: Albumin‐bilirubin score
Authors: Chan Anthony W H , Chan Ronald C K , Wong Grace L H , Wong Vincent W S , Choi Paul C L , Chan Henry L Y , To Ka‐Fai
Published: March 2015

Background and Aim

Serum albumin and bilirubin are the most significant independent prognostic factors to predict hepatic events in patients with primary biliary cirrhosis (PBC). We aimed to investigate the prognostic significance of a new prognostic score, the albumin‐bilirubin (ALBI) score, among PBC patients.

Methods

In a retrospective longitudinal cohort of 61 Chinese PBC patients with follow‐up period up to 18.3 years, the prognostic performance of the ALBI in prediction of hepatic events was compared with other well‐established prognostic scores: Child–Pugh score, model of end‐stage liver disease, Mayo risk score, Yale, European, and Newcastle models.

Results

Fifteen patients (24.6%) developed hepatic events during follow‐up. The c‐index (0.894) and χ2 by likelihood ratio test (36.34) of the ALBI score were highest in comparison to other models. The ALBI score was the only independent prognostic factor by multivariate analysis and its adjusted hazard ratio of developing hepatic event was 27.8 (P < 0.001). There were three prognostically different groups stratified by the ALBI score: ALBI grade 1 (≤ −2.60), grade 2 (> −2.60 to −1.39), and grade 3 (> −1.39) groups. The 2‐, 5‐, and 10‐year event‐free survivals for grade 1, grade 2, and grade 3 groups were 100.0% versus 100.0% versus 57.1%, 100.0% versus 88.5% versus 14.3%, and 100.0% versus 81.7% versus 0.0%, respectively (P < 0.001).

Conclusion

The ALBI score is readily derived from a blood test without using those factors evaluated subjectively or obtained by invasive procedures. It is an independent prognostic factor for PBC patients and provides better/similar prognostic performance compared with other prognostic scores.
Prognostic value of long noncoding RNA HOTAIR in digestive system malignancies
Authors: Wang Shuai , Wang Zhou
Published: March 2015

Background and Aim

HOX transcript antisense intergenic RNA (HOTAIR), a well‐known long noncoding RNA, has been found to play significant roles in several tumors. However, the clinical application value of HOTAIR in digestive system malignancies remains to be clarified. We aimed to explore comprehensively the potential role of HOTAIR as a prognostic indicator in digestive system malignancies.

Methods

Systematic search was performed in Pubmed, Embase, Cochrane Library, and Web of Science until July 5, 2014. A quantitative meta‐analysis was conducted with standard statistical methods for eligible papers on the prognostic value of HOTAIR in digestive system cancers.

Results

A total of 1059 patients from 13 studies were included in the meta‐analysis. A significant association was found between HOTAIR abundance and poor overall survival (OS) of patients with digestive system malignancies, with pooled hazard ratio (HR) of 2.587 (95% confidence interval [CI]: 2.054–3.259, P < 0.001). By combining HRs from Cox multivariate analyses, we found HOTAIR was an independent prognostic factor for OS without obvious heterogeneity (HR: 2.405, 95% CI: 1.883–3.0722, P < 0.001). Subgroup analysis showed that tumor type, histology type, region, publication year, sample size, and quality score did not alter the predictive value of HOTAIR as an independent factor for survival. Meta‐regression and sensitivity analysis both suggested the reliability of our findings. A slight publication bias was observed. After adjustment by nonparametric “trim‐and‐fill” method, the corrected HRs had no significant change.

Conclusion

HOTAIR could be exploited as a novel prognostic biomarker for patients with digestive system malignancies.
Endo‐β‐1,4‐glucanases impact plant cell wall development by influencing cellulose crystallization
Authors: Glass Magdalena , Barkwill Sarah , Unda Faride , Mansfield Shawn D.
Published: March 2015

Cell walls are vital to the normal growth and development of plants as they protect the protoplast and provide rigidity to the stem. Here, two poplar and Arabidopsis orthologous endoglucanases, which have been proposed to play a role in secondary cell wall development, were examined. The class B endoglucanases, PtGH9B5 and AtGH9B5, are secreted enzymes that have a predicted glycosylphosphatidylinositol anchor, while the class C endoglucanases, PtGH9C2 and AtGH9C2, are also predicted to be secreted but instead contain a carbohydrate‐binding module. The poplar endoglucanases were expressed in Arabidopsis using both a 35S promoter and the Arabidopsis secondary cell wall‐specific CesA8 promoter. Additionally, Arabidopsis t‐DNA insertion lines and an RNAi construct was created to downregulate AtGH9C2 in Arabidopsis. All of the plant lines were examined for changes in cell morphology and patterning, growth and development, cell wall crystallinity, microfibril angle, and proportion of cell wall carbohydrates. Misregulation of PtGH9B5/AtGH9B5 resulted in changes in xylose content, while misregulation of PtGH9C2/AtGH9C2 resulted in changes in crystallinity, which was inversely correlated with changes in plant height and rosette diameter. Together, these results suggest that these endoglucanases affect secondary cell wall development by contributing to the cell wall crystallization process.
Effects of music on psychophysiological responses and opioid dosage in patients undergoing total knee replacement surgery
Authors: Chen Hsin‐Ji , Chen Tsung‐Ying , Huang Chiung‐Yu , Hsieh Yuan‐Mei , Lai Hui‐Ling
Published: March 2015

Aim

The present authors examined the effects of listening to music on psychophysiological parameters (blood pressure, heart rate, and respiratory rate) during preoperative and postoperative days and determined whether listening to music could lower pain intensity and opioid dosage during postoperative days in patients who underwent total knee replacements.

Methods

This was a two group repeated measures design for 30 subjects aged 53–85 years who were scheduled for total knee replacement. Subjects were randomly assigned to either a music group or a control group. Psychophysiological parameters were obtained from patients' monitors. A visual analog scale was used to assess postoperative pain. Opioid dosage was recorded and converted to standardized units. Mann–Whitney U‐test and generalized estimating equation analysis were used to compare groups.

Results

Respiratory rates while in the surgical waiting area were lower for the music group than for the control group (P = 0.02). There was no significant difference between these groups for blood pressure, heart rate, pain intensity, or opioid dosage. However, a within‐group comparison showed that systolic blood pressure in the music group was significantly and consistently decreased during postoperative recovery (Wald = 9.21, P = 0.007).

Conclusion

These results suggest that listening to music stabilized systolic blood pressure in patients during postoperative recovery. However, the effects of music on psychophysiological parameters, pain intensity, and opioid dosage in a surgical setting require further research.
Rethinking family‐centred care for the child and family in hospital
Authors: Tallon Mary M , Kendall Garth E , Snider Paul D
Published: March 2015

Aims and objectives

This paper presents and discusses an alternative model of family‐centred care (FCC) that focuses on optimising the health and developmental outcomes of children through the provision of appropriate support to the child's family.

Background

The relevance, meaning and effectiveness of FCC have been challenged recently. Studies show that parents in hospital often feel unsupported, judged by hospital staff and uncertain about what care they should give to their child. With no convincing evidence relating FCC to improved child health outcomes, it has been suggested that FCC should be replaced with a new improved model to guide the care of children in hospital.

Design

This integrative review discusses theory and evidence‐based literature that supports the practice of an alternative model of FCC that is focused on the health and developmental outcomes of children who are seriously ill, rather than the organisational requirements of children's hospitals.

Methods

Theories and research findings in a wide range of disciplines including epidemiology, psychology, sociology, anthropology and neuroscience were accessed for this discussion. Nursing literature regarding partnership building, communication and FCC was also accessed.

Discussion

This paper discusses the benefits of applying a bioecological model of human development, the family and community resource framework, the concepts of allostatic load and biological embedding, empowerment theory, and the nurse–family partnership model to FCC.

Conclusion

While there is no direct evidence showing that the implementation of this alternative model of FCC in the hospital setting improves the health and developmental outcomes of children who are seriously ill, there is a great deal of evidence from community nursing practice that suggests it is very likely to do so.

Relevance to clinical practice

Application of these theoretical concepts to practice has the potential to underpin a theory of nursing that is relevant for all nurses irrespective of the age of those they care for and the settings within which they work.
Evolution of tinea capitis in the Nanchang area, Southern China: a 50‐year survey (1965–2014)
Authors: Zhan Ping , Geng Chengfang , Li Zhihua , Jin Yun , Jiang Qing , Tao Li , Luo Yunpeng , Xiong Zhiwei , Wu Shaoxi , Li Dongmei , Liu Weida , de Hoog G. Sybren
Published: March 2015

Tinea capitis remains a common public health problem worldwide especially in developing areas. Aetiologic agents and clinical pattern vary with geography and history of socioeconomic conditions. Three community surveys and a prospective study were carried out over the past 50 years (1965–2014) in the Qingyunpu District of Nanchang, Southern China. Clinical presentation and spectrum of aetiological agents were monitored to understand the evolution of tinea capitis. In 1965 favus was highly epidemic andTrichophyton schoenleiniipresented as the overwhelming aetiological agents of scalp infection in the study area, with a prevalence of 3.41% of the population. During a governmental campaign to eliminate tinea capitis initiated in mid of 1960s, favus was successfully controlled and the prevalence decreased to less than 0.01% in 1977. After that period, clinical presentation and spectrum of fungi changed with social development.Trichophyton schoenleiniiwas replaced byTrichophyton violaceumandTrichophyton mentagrophytes. Nowadays, the species corresponds with a dominant black dot type of tinea capitis in the Nanchang area. The prevalence of causative agents of tinea capitis is not only related to geography but also to socioeconomic factors. Multiple factors have to be considered for the management for control of this disease.
In vitro susceptibility patterns of clinically important Trichophyton and Epidermophyton species against nine antifungal drugs
Authors: Badali Hamid , Mohammadi Rasoul , Mashedi Olga , de Hoog G. Sybren , Meis Jacques F.
Published: March 2015

Despite the common, worldwide, occurrence of dermatophytes, little information is available regarding susceptibility profiles against currently available and novel antifungal agents. A collection of sixty‐eight clinical Trichophyton species and Epidermophyton floccosum were previously identified and verified to the species level by sequencing the internal transcribed spacer (ITS) regions of rDNA. MICs of amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, isavuconazole, terbinafine and MECs of caspofungin and anidulafungin were performed based on CLSI M38‐A2. The resulting MIC90s of all strains were, in increasing order, as follows: terbinafine (0.063 mg l−1); posaconazole (1 mg l−1); isavuconazole and anidulafungin (2 mg l−1); itraconazole, voriconazole, amphotericin B, and caspofungin (4 mg l−1) and fluconazole (>64 mg l−1). These results confirm that terbinafine is an excellent agent for treatment of dermatophytosis due to T. rubrum, T. mentagrophytes, T. verrucosum, T. schoenleinii and E. floccosum. In addition, the new azoles POS and ISA are potentially useful antifungals to treat dermatophytosis. However, the clinical effectiveness of these novel antifungals remains to be determined.
Redefining fine roots improves understanding of below‐ground contributions to terrestrial biosphere processes
Authors: McCormack M. Luke , Dickie Ian A. , Eissenstat David M. , Fahey Timothy J. , Fernandez Christopher W. , Guo Dali , Helmisaari Heljä‐Sisko , Hobbie Erik A. , Iversen Colleen M. , Jackson Robert B. , Leppälammi‐Kujansuu Jaana , Norby Richard J. , Phillips Richard P. , Pregitzer Kurt S. , Pritchard Seth G. , Rewald Boris , Zadworny Marcin
Published: March 2015

Fine roots acquire essential soil resources and mediate biogeochemical cycling in terrestrial ecosystems. Estimates of carbon and nutrient allocation to build and maintain these structures remain uncertain because of the challenges of consistently measuring and interpreting fine‐root systems. Traditionally, fine roots have been defined as all roots ≤ 2 mm in diameter, yet it is now recognized that this approach fails to capture the diversity of form and function observed among fine‐root orders. Here, we demonstrate how order‐based and functional classification frameworks improve our understanding of dynamic root processes in ecosystems dominated by perennial plants. In these frameworks, fine roots are either separated into individual root orders or functionally defined into a shorter‐lived absorptive pool and a longer‐lived transport fine‐root pool. Using these frameworks, we estimate that fine‐root production and turnover represent 22% of terrestrial net primary production globally – a c. 30% reduction from previous estimates assuming a single fine‐root pool. Future work developing tools to rapidly differentiate functional fine‐root classes, explicit incorporation of mycorrhizal fungi into fine‐root studies, and wider adoption of a two‐pool approach to model fine roots provide opportunities to better understand below‐ground processes in the terrestrial biosphere.

Contents

Summary
505

I.
Introduction
506

II.
Ordered variation in fine‐root traits – different functions of different roots
506

III.
Pitfalls and platforms – understanding bias and improving estimates of root processes
508

IV.
Moving forward using root orders and functional classifications
512

V.
Can we integrate mycorrhizal fungi with root classifications?
513

VI.
Conclusions and recommendations
514

Acknowledgements
515

References
515
Some imminent but overlooked preanalytical and analytical challenges currently facing biomarkers and companion diagnostics
Authors: Halim Abdel‐Baset
Published: March 2015

An incredibly high failure rate in the pharmaceutical industry has positioned personalized medicine with its prerequisite drug–diagnostic codevelopment, commonly known as companion diagnostics (CDx), in the frontline as an potential rescuer. This hopefulness is potentiated by the recent major advances and competitiveness in molecular diagnostics, making laboratory tests widely accessible at affordable prices. If executed correctly, biomarkers and CDx can potentially help the drug industry by enhancing the probability of success and possibly accelerating time to market; help the diagnostics industry develop tests utilizing precious, clinically annotated human samples; and, more importantly, benefit patients by supporting accurate diagnosis and selection of the most efficacious and least toxic therapies. However, this spectacular road is not yet paved, and it faces an enormous number of challenges. This paper will list these challenges and highlight some critical problems with representative examples of imminent but still overlooked preanalytical and analytical variables that can defeat the whole purpose of biomarkers and CDx and mislead drug developers and clinicians. The paper will provide some suggestions for mitigation.
The long‐run impact of idiosyncratic and common shocks on industry output inGhana
Authors: Adom Philip Kofi , Amakye Kwaku , Barnor Charles , Quartey George
Published: March 2015

This study explores the long‐run impact of idiosyncratic and common shocks on industry output in Ghana while controlling for the effects of investment. In order to deal with the second‐order bias problem, this study employed canonical cointegration and fully modified ordinary least‐squares (OLS) regressions, which are more robust to second‐order bias problems. Different models are, therefore, specified and estimated. Fully modifiedOLSand canonical cointegration are extended in successive steps in order to verify if the inclusion of idiosyncratic and common shocks improves the statistical properties of the model. Secondly, a backward approach, in which idiosyncratic and common shocks are excluded successively, is also adopted. Preliminary findings showed signs of long‐run equilibrium. The a priori expectation and the statistical importance of investment are established in both fully modified OLS and canonical cointegration models. This result is robust using both theBartlett andParzen kernels. However, while the elasticity value for investment is invariant to the model and kernel type used for fully modifiedOLS, the opposite result is found for canonical cointegration. Importantly, the absolute value of the investment elasticity is kept within the limits of 0 and 1. The impacts of idiosyncratic and common shocks are negative and statistically significant in the long run for both fully‐modifiedOLSand canonical cointegration. This result is robust to theBartlett andParzen kernels. Result based on the fully modifiedOLSalso showed that the sizes of the elasticity values for both idiosyncratic and common shocks are sensitive to the model type and kernel type used. Despite the differences in the elasticity values, result for both models are qualitatively similar.
Dynamic panel data approaches for estimating oil demand elasticity
Authors: Javan Afshin , Zahran Nahl
Published: March 2015

This study examines the general relationships between crude oil consumption, real oil price and real GDP using a quarterly time series from 1993 to 2012. Specifically, the long‐term and short‐term GDP and price elasticities of oil consumption per capita were estimated using dynamic panel and pooled data regressions based on Nerlove's oil demand model for 25 countries that represent 75 per cent of global oil demand. Price elasticities were found for most OECD countries. These estimates were low and consistent with previous estimates. According to the study results, the short‐run price elasticity ranged between −0.05 and −0.20 and the long‐run between −0.11 and −0.36. Price elasticities for most non‐OECD countries were either positive or insignificant. Estimates of GDP elasticities varied. The short‐run GDP elasticity was between 0.15 and 1.09, while the long‐run was between 0.21 and 1.54. On average, income elasticity for OECD countries was found to be slightly higher than for non‐OECD countries. Contrary to expectations, we found China's income elasticity to be 0.34 in the short run, but it was 0.76 in the long run.
Energy efficiency in OPEC member countries: analysis of historical trends through the energy coefficient approach
Authors: Al‐Rashed Yazeed , León Jorge
Published: March 2015

Period‐wise energy coefficients for members of the Organization of the Petroleum Exporting Countries (OPEC) were calculated, showing diverse behaviour among them. Behaviour of aggregate OPEC coefficients reflects the general trend among its member nations. Acceleration of transportation fuel demand fuelled high intensities in the mid‐1970s. An overall economic downturn in the 1980s did not dampen demand growth, but in fact accelerated in the industrial and household, public and commercial (HPC) sectors, thus keeping energy coefficients above 1. Energy coefficients were headed towards unity in the 1990s, before finally settling under 1 in the 2000s. We caution from interpreting these developments as improvements in efficiency, as OPEC member countries have not become ‘post‐industrial’ as more value‐added industries, infrastructure development and stability encourage consumption. Electricity coefficients can be used as a proxy for consumer behavioural efficiency, as the HPC sector is its largest consumer. After the 1990s, almost all OPEC member countries had higher electricity coefficients than energy ones, due to reasons spanning from higher urbanisation and population growth rates, to low electricity prices. This suggests that electricity use in the industrial and HPC sectors will be a major driver of future demand growth for those countries, especially as their service sector grows and their economies diversify.
A VARX modelling of energy intensity interactions between China, the United States, Japan and EU
Authors: Akal Mustafa
Published: March 2015

This study attempts to predict energy intensity interactions between China, the United States, Japan and EU by developing a restricted VARX model by proposing energy intensities of the countries interact with each others, and gross domestic product (GDP) levels per capita and Organization of Petroleum Exporting Countries (OPEC) oil‐based current energy prices affect energy intensities of the countries based upon the direction of group causalities. There exist significant causal interactions between energy intensities of the countries up to lag five either increasing efficiency or not. China's current GDP level affects its own energy use and EU's energy intensity positively, on the other way; EU's current GDP level affects only China's energy intensity while Japan's current GDP level only affects its own energy intensity negatively, ceteris paribus. It is found that OPEC oil‐based current energy prices only affect the United States' energy intensity but not others' energy intensity, ceteris paribus, for the period of 1971–2009. Evaluating cumulative effects of energy intensities of all countries, it is found that each country has experienced higher energy intensity and consumed energy less efficiently even there have been existing new technology‐embodied equipments used and alternative energy sources developed in energy consumption for the years.
Slackline training and neuromuscular performance in seniors: A randomized controlled trial
Authors: Donath L. , Roth R. , Zahner L. , Faude O.
Published: March 2015

Slackline training (balancing on nylon ribbons) has been shown to improve neuromuscular performance in children and adults. Comparable studies in seniors are lacking. Thus, 32 seniors were randomly assigned [strata: age, gender, physical activity (PA)] to an intervention [INT; n = 16, age: 65 ± 4 years, PA: 9 ± 5 h/week] or control [CON, n = 16, age: 63 ± 4 years, PA: 8 ± 4 h/week] group. Slackline training was given for 6 weeks (3 times per week, attendance 97%). Static and slackline standing balance performance, force development, and maximal strength of the ankle muscles were assessed before and after slackline training. Muscle activity (lower limb and trunk) was recorded during balance testing. Moderate to large group × time interactions (0.02 < P < 0.04, 0.11 < ηp2 < 0.17) in favor of INT were found for slackline standing times (INT: left, +278%, P = 0.02; right, +328%, P = 0.03; tandem, +94%, P = 0.007) and muscle activity during single‐limb slackline standing [INT: right: rectus abdominis (RA), P = 0.003, −15%; multifidus (MF), P = 0.01, −15%; left: tibialis anterior (TIB), P = 0.03, −12%; soleus (SOL), P = 0.006, −18%; RA, P = 0.04, −11%; MF, P = 0.01, −16%; gastrocnemius medialis (GM), P = 0.02, −19%]. Static balance performance, ankle strength, and power were not affected. Slackline training induced large task‐specific improvements of slackline standing performance accompanied with reductions of lower limb and trunk muscle activity. Transfer effects to static balance and strength measures seem limited.
Neck muscle activity in skydivers during parachute opening shock
Authors: Lo Martire R. , Gladh K. , Westman A. , Lindholm P. , Nilsson J. , Äng B. O.
Published: March 2015

This observational study investigated skydiver neck muscle activity during parachute opening shock (POS), as epidemiological data recently suggested neck pain in skydivers to be related to POS. Twenty experienced skydivers performed two terminal velocity skydives each. Surface electromyography quantified muscle activity bilaterally from the anterior neck, the upper and lower posterior neck, and the upper shoulders; and two triaxial accelerometers sampled deceleration. Muscle activity was normalized as the percentage of reference maximum voluntary electrical activity (% MVE); and temporal muscle activity onset was related to POS onset. Our results showed that neck muscle activity during POS reached mean magnitudes of 53–104% MVE, often exceeding reference activity in the lower posterior neck and upper shoulders. All investigated muscle areas’ mean temporal onsets occurred <50 ms after POS onset (9–34 ms latencies), which is consistent with anticipatory motor control. The high muscle activity observed supports that the neck is under substantial strain during POS, while temporal muscle activation suggests anticipatory motor control to be a strategy used by skydivers to protect the cervical spine from POS. This study's findings contribute to understanding the high rates of POS‐related neck pain, and further support the need for evaluation of neck pain preventative strategies.
Former male elite athletes have better metabolic health in late life than their controls
Authors: Laine M. K. , Eriksson J. G. , Kujala U. M. , Kaprio J. , Loo B.‐M. , Sundvall J. , Bäckmand H. M. , Peltonen M. , Jula A. , Sarna S.
Published: March 2015

Elite‐class athletes have longer life expectancy and lower risk for chronic noncommunicable diseases possibly because of physically active and healthier lifestyle. In this study, we assessed former male Finnish elite‐class athletes’ (n = 392) and their matched controls’ (n = 207) body composition, and risk for the metabolic syndrome (MS) and nonalcoholic fatty liver disease (NAFLD) in later life. Compared with the controls, the former athletes had lower body fat percentage (24.8% vs 26.0%, P = 0.021), lower risk for MS [odds ratio (OR) 0.57, 95% confidence interval (CI) 0.40–0.81], and NAFLD (OR 0.61, 95% CI 0.42–0.88). High volume of current leisure‐time physical activity (LTPA) was associated with lower body fat percentage (P for trend < 0.001). When current volume of LTPA increased 1 MET h/week, the risk of MS and NAFLD decreased (OR 0.99, 95% CI 0.98–0.99 and OR 0.97, 95% CI 0.96–0.98, respectively). Although a career as an elite‐class athlete during young adulthood may help to protect from developing metabolic syndrome, present exercise levels and volume of LTPA seem equally important as well.
Parameter-Dependent Lyapunov Functions in the Robust Control of Discrete Linear Repetitive Processes Using Previous Pass-Windowed Information
Authors: Cichy Błażej , Galkowski Krzysztof , Rogers Eric
Published: March 2015

The variables in multidimensional systems are functions of more than one indeterminate, and such systems cannot be controlled by standard systems theory. This paper considers a subclass of these systems that operate over a subset of the upper-right quadrant of the two-dimensional (2D) plane in the discrete domain with a specified recursive structure known as repetitive processes. Physical examples of such processes are known and also their representations can be used in the analysis of other classes of systems, such as iterative learning control. This paper gives new results on the use of the parameter-dependent Lyapunov functions for stability analysis and controls law design of a subclass of repetitive processes that arise in application areas. These results aim to eliminate or reduce the effects of model parameter uncertainty.
An Axial Turbobrake
Authors: Goodisman M. I. , Oldfield M. L. G. , Kingcombe R. C. , Jones T. V. , Ainsworth R. W. , Brooks A. J.
Published: March 2015

The Axial Turbobrake (Patent applied for) is a novel turbomachine which can be used to absorb power generated by test turbines. Unlike a compressor there is no pressure recovery through the turbobrake. This simplifies the aerodynamic design and enables high stage loadings to be achieved. The blades used have high turning two dimensional profiles.

This paper describes a single stage axial turbobrake, which is driven by the exhaust gas of the test turbine and is isolated from the turbine by a choked throat. In this configuration no fast acting controls are necessary as the turbobrake operates automatically with the turbine flow.

Tests on a 0.17 scale model, show that the performance is close to that predicted by a simple two-dimensional theory, and demonstrate that the turbobrake power absorption can be controlled and hence matched to that typically produced by the first stage of a modern highly loaded transonic turbine. A full size axial turbobrake will be used in a short duration rotating turbine experiment in an Isentropic Light Piston Tunnel at RAE Pyestock.
Effect of Cold Work and Aging Upon the Properties of a Ni-Mo-Cr Fastener Alloy
Authors: Rothman M. F. , Srivastava S. K.
Published: March 2015

HAYNES® alloy 242 is a promising new Ni-Mo-Cr alloy for high-strength, high-temperature aerospace fastener applications. Age-hardenable by virtue of a long-range-order strengthening mechanism, 242™ alloy is capable of developing very high strength, particularly in the cold-worked condition. A key difference from other fastener materials is its attendant good ductility. The relationship between the amount of cold work, aging temperature and time, and the properties of this alloy have not been previously explored in detail. In the present work, the nature of the interaction between cold work and aging will be examined, and the properties of the material relevant to aerospace fastener applications will be described.
Design Method for Subsonic and Transonic Cascade With Prescribed Mach Number Distribution
Authors: Léonard O. , Van Den Braembussche R. A.
Published: March 2015

An iterative procedure for blade design, using a Time Marching procedure to solve the unsteady Euler equations in the blade-to-blade plane is presented. A flow solver, which performs the analysis of the flow field for a given geometry, is transformed into a design method. This is done by replacing the classical slip condition (no normal velocity component) by other boundary conditions, in such a way that the required pressure or Mach number distribution may be imposed directly on the blade. The unknowns are calculated on the blade wall using the so-called compatibility relations.

Since the blade shape is not compatible with the required pressure distribution, a non-zero velocity component normal to the blade wall evolves from the new flow calculation. The blade geometry is then modified by resetting the wall parallel to the new flow field, using a transpiration technique, and the procedure is repeated until the calculated pressure distribution has converged to the required one.

Examples for both subsonic and transonic flows are presented and show a rapid convergence to the geometry required for the desired Mach number distribution. An important advantage of the present method is the possibility to use the same code for the design and the analysis of a blade.
GE LM2500 Marine Gas Turbine Experience Update
Authors: Reid Robert E. , Hartranft John J.
Published: March 2015

This paper provides a status of the ship propulsion system applications, the marine operational experience, and the demonstrated reliability of the GE LM2500 gas turbine. The unique maintenance approach that has been developed by the U.S. Navy and GE to maximize the availability of the LH2500 is also described.
Improved Gas Turbine Reliability and Availability With Static Starting Equipment
Authors: Denesdi L. , Wittwer M.
Published: March 2015

Either a conventional motor starting system or a static starting system can be used to accelerate a large gas turbine from standstill to self-sustaining speed. In the motor-starting configuration, the gas turbine rotor is accelerated by a cranking electromotor. In a static starting configuration, a current with a variable frequency is supplied to the generator stator. The synchronous generator then operates — during the start-up — as a synchronous motor, accelerating the gas turbine rotor. The static starting system has a “soft start” capability, i.e., the power required for start-up increases gradually, without surging.

This paper outlines the operating principle of the static starting method. A comparative analysis of the reliability and availability of the conventional motor starting and static starting configurations is presented.
Design and Operating Experience of Selective Catalytic Reduction Systems for NOx Control in Gas Turbine Systems
Authors: Cho S. M. , Seltzer A. H. , Tsutsui Z.
Published: March 2015

The design and operating experience of the Selective Catalytic Reduction (SCR) systems for denitrification of flue gas in utility and industrial gas turbine applications is presented. The paper will discuss the general SCR design approaches and the effects on the NOx removal efficiency of various design and operating parameters such as gas temperature, velocity and composition, NOx content, catalyst material and type, quantity of ammonia injected, aging, and pressure drop limitation. Two different types of ammonia injection methods (namely, anhydrous and aqueous ammonia injections) and attendant ammonia injection control schemes are described. A brief summary of SCR operating experience with power-generating gas turbines and process heaters/boilers concludes the paper.
Preliminary Experience With an Expert System Providing Initial Centrifugal Compressor Sizing for Performance Prediction and Analysis
Authors: Schoonmaker Peter M.
Published: March 2015

There are many problems in turbomachinery which do not lend themselves to numerical analysis. One such area is the preliminary design of centrifugal compressor stages. It seems likely that expert systems technology and object-oriented programming techniques will be able to make some impact on this class of problems. This paper presents the results of the first phase of a project designed to test this assumption.

This paper describes a simple methodology for establishing the initial parameters of centrifugal compressor stages up to a pressure ratio of 5.0. The method combines heuristic rules and empirical relationships, with some very simple optimization routines. It requires very little input from the user other than aerodynamic performance requirements. Phase 1 of this project uses this methodology to estimate the initial geometry of a centrifugal compressor impeller.
Convective Transport Phenomena on the Suction Surface of a Turbine Blade Including the Influence of Secondary Flows Near the Endwall
Authors: Chen P. H. , Goldstein R. J.
Published: March 2015

A naphthalene sublimation technique is employed to study the mass transfer distribution on the suction (convex) surface of a simulated turbine blade. Comparison with a heat transfer study shows good agreement in the general trends in the region of two-dimensional flow on the blade.

Near the endwall, local convective coefficients on the suction surface are obtained at 4608 locations from two separate runs. The secondary flows in the passage significantly affect the mass transfer rate on the suction surface and their influence extends to a height of 75% of the chord length, from the endwall, in the trailing edge region. The mass transfer rate in the region near the endwall is extremely high due to small but intense vortices. Thus, a large variation in the mass transfer distribution occurs on the suction surface, from a mass transfer Stanton number of 0.0005 to a maximum of 0.01. In the two-dimensional flow region, the mass transfer distributions at two different Reynolds number are presented.
Ceramic Oxide Coatings for the Corrosion Protection of Silicon Carbide
Authors: Van Roode Mark , Price Jeffrey R. , Stala Christopher
Published: March 2015

Silicon carbide is currently used as a structural material for heat exchanger tubes and related applications because of its excellent thermal properties and oxidation resistance. Silicon carbide suffers corrosion degradation, however, in the aggressive furnace environments of industrial processes for aluminum remelting, advanced glass melting, and waste incineration. Adherent ceramic oxide coatings developed at Solar Turbines Incorporated with the support of the Gas Research Institute, have shown to afford corrosion protection to silicon carbide in a simulated aluminum remelt furnace environment as well as in laboratory type corrosion testing. The coatings are also protective to silicon carbide-based ceramic matrix composites.
An Expert System for Trend Analysis Applied to Turbomachinery
Authors: Van Hardeveld Thomas
Published: March 2015

With the advent of computerized monitoring techniques, it is becoming evident that more automated methods of trend analysis and other diagnostic techniques are both possible and necessary. The implementation of a computerized health monitoring system has led to research into techniques for identifying trend behavior which can be used to detect equipment deterioration. The result has been the development of statistical techniques to characterize generic trend behavior and of an expert system to translate these into a diagnosis of equipment deterioration.
Turbine-Compressor Train Uprated for 30% Increase in Gas Flow
Authors: Breon C. D. (Charlton) , Veth D. R. (Daniel)
Published: March 2015

A turbine-compressor train consisting of a General Electric MS5001 Model R single-shaft gas turbine, a Philadelphia Gear speed-increasing gearbox, and a Dresser-Clark centrifugal compressor was uprated for 30% increased gas throughput. This train is one of thirteen units operated by ARCO Alaska, Inc. for high pressure natural gas injection service in Alaska’s Prudhoe Bay Oil Field. The uprate included an in-place conversion of the gas turbine from a Model R to a Model P configuration. This paper describes the engineering, planning, and implementation activities that led up to the successful uprate of this train with only a 24 day equipment outage.
Computation of Flow Past a Turbine Blade With and Without Tip Clearance
Authors: Briley W. R. , Roscoe D. V. , Gibeling H. J. , Buggeln R. C. , Sabnis J. S. , Johnson P. D. , Huber F. W.
Published: March 2015

Three-dimensional solutions of the ensemble-averaged Navier-Stokes equations have been computed for a high-turning turbine rotor passage, both with and without tip clearance effects. The geometry is Pratt & Whitney’s preliminary design for the Generic Gas Generator Turbine (GGGT), having an axial chord of 0.5 inch and turning angle of about 160 degrees. The solutions match the design Reynolds number of 3x 106/inch and design inflow/outflow distributions of flow quantities. The grid contains 627,000 points, including 20 radial points in the clearance gap of 0.015 inch, and has a minimum spacing of 10−4 inch adjacent to all surfaces. The solutions account for relative motion of the blade and shroud surfaces and include a backstep on the shroud. Computed results are presented which show the general flow behavior, especially near the tip clearance and backstep regions. The results are generally consistent with experimental observations for other geometries having thinner blades and smaller turning angles. The leakage flow includes some fluid originally in the freestream at 91 percent span. Downstream, the leakage flow behaves as a wall jet directed at 100 degrees to the main stream, with total pressure and temperature higher than the freestream. Radial distributions of circumferentially-averaged flow quantities are compared for solutions with and without tip leakage flow. Two-dimensional solutions are also presented for the mid-span blade geometry for design and off-design inflow angles.
Principles of the ITS Ceramic Research Combustor Design: Segmented Flame Tube and Staged Combustion
Authors: Pfeiffer A. , Schulz A. , Wittig S.
Published: March 2015

At the Institute for Thermal Turbomachinery in Karlsruhe a small research combustor was developed to investigate the applicability of high temperature loaded ceramic components under near ideal engine conditions. The design concept includes film evaporation of the liquid fuel and staged combustion with variable air supply. The combustor liner is segmented and consists of ceramic elements. For the prediction of the failure probability the newly developed fracture statistic code CERITS was used.

The key features of the combustor and the test facility are described and preliminary experimental results of the first test phase are reported with emphasis on emission measurements and durability of the ceramic components. The determining parameters under consideration are thermal power, air/fuel ratio and the temperature of the preheated inlet air.