bluuebunny/crossref_metadata_2025 huggingface dataset:
Supporting Well‐Being in Retirement through Meaningful Social Roles: Systematic Review of Intervention Studies
Authors: HEAVEN BEN , BROWN LAURA J.E. , WHITE MARTIN , ERRINGTON LINDA , MATHERS JOHN C. , MOFFATT SUZANNE
Published: June 2013

Context

The marked demographic change toward greater proportions of older people in developed nations poses significant challenges for health and social care. Several studies have demonstrated an association between social roles in later life and positive health and well‐being outcomes. After retiring from work, people may lose roles that provide purpose and social contacts. The outcomes of interventions to promote social roles in retirement have not been systematically reviewed.

Methods

We examined three research questions: (1) What kinds of intervention have been developed to promote social roles in retirement? (2) How much have they improved perceived roles? (3) Have these roles improved health or well‐being? We included those studies that evaluated the provision of social roles; used a control or comparison group; targeted healthy retirement‐transition adults who were living in the community; provided an abstract written in English; took place in a highly developed nation; and reported social role, health, or well‐being outcomes. We searched eight electronic databases and combined the results with hand searches.

Findings

Through our searches, we identified 9,062 unique publications and eleven evaluative studies of acceptable quality, which reported seven interventions that met our inclusion criteria. These interventions varied in year of inception and scope, but only two were based outside North America. The studies rarely reported thequalityor meaning of roles. Only three studies used random allocation, thus limiting inferences of causality from these studies. Interventions providingexplicitroles and using supportive group structures were somewhat effective in improving one or more of the following: life satisfaction, social support and activity, physical health and activity, functional health, and cognition.

Conclusions

Social role interventions may improve health and well‐being for people in retirement transition. Future research should improve the quality of intervention and assessment and look at which interventions are most effective and acceptable in facilitating social roles for diverse older populations.
Potential for bowhead whale entanglement in cod and crab pot gear in the Bering Sea
Authors: Citta, John J. , Burns John J. , Quakenbush Lori T. , Vanek Vicki , George John C. , Small Robert J. , Heide‐Jørgensen Mads Peter , Brower Harry
Published: June 2013

Bowhead whales (Balaena mysticetus) of the western Arctic stock winter in ice‐covered continental shelf regions of the Bering Sea, where pot fisheries for crabs (Paralithodes and Chionoecetes spp.) and Pacific cod (Gadus macrocephalus) pose a risk of entanglement. In the winter of 2008–2009 and 2009–2010 the spatial distribution of 21 satellite tagged bowhead whales partially overlapped areas in which pot fisheries for cod and blue king crab (Paralithodes platypus) occurred. However, these fisheries ended before whales entered the fishing areas, thus avoiding temporal overlap. A fishery for snow crab (Chionoecetes opilio) typically runs from January to May and provides the greatest potential for bowhead whales to encounter active pot gear. Tagged whales did not enter the area of the snow crab fishery during this study and generally remained in areas with >90% sea ice concentration, which is too concentrated for crab boats to penetrate. Pack ice sometimes overruns active fishing areas, resulting in lost gear, which is the most likely source of entanglement. The western Arctic stock of bowhead whales was increasing as of 2004; as such, incidental mortality from commercial pot fisheries is probably negligible at this time. Regardless, entanglement may increase over time and should be monitored.
Bacilliform DNA‐containing plant viruses in the tropics: commonalities within a genetically diverse group
Authors: Borah Basanta K. , Sharma Shweta , Kant Ravi , Johnson A. M. Anthony , Saigopal Divi Venkata Ramana , Dasgupta Indranil
Published: June 2013

Plant viruses, possessing a bacilliform shape and containing double‐stranded DNA, are emerging as important pathogens in a number of agricultural and horticultural crops in the tropics. They have been reported from a large number of countries in African and Asian continents, as well as from islands from the Pacific region. The viruses, belonging to two genera, Badnavirus and Tungrovirus, within the family Caulimoviridae, have genomes displaying a common plan, yet are highly variable, sometimes even between isolates of the same virus. In this article, we summarize the current knowledge with a view to revealing the common features embedded within the genetic diversity of this group of viruses.

Taxonomy

Virus; order Unassigned; family Caulimoviridae; genera Badnavirus and Tungrovirus; species Banana streak viruses, Bougainvillea spectabilis chlorotic vein banding virus, Cacao swollen shoot virus, Citrus yellow mosaic badnavirus, Dioscorea bacilliform viruses, Rice tungro bacilliform virus, Sugarcane bacilliform viruses and Taro bacilliform virus.

Microbiological properties

Bacilliform in shape; length, 60–900 nm; width, 35–50 nm; circular double‐stranded DNA of approximately 7.5 kbp with one or more single‐stranded discontinuities.

Host range

Each virus generally limited to its own host, including banana, bougainvillea, black pepper, cacao, citrus species, Dioscorea alata, rice, sugarcane and taro.

Disease symptoms

Foliar streaking in banana and sugarcane, swelling of shoots in cacao, yellow mosaic in leaves and stems in citrus, brown spot in the tubers in yam and yellow–orange discoloration and stunting in rice.

Useful websites

http://www.dpvweb.net.
The oxygen isotope enrichment of leaf‐exported assimilates – does it always reflect lamina leaf water enrichment?
Authors: Gessler Arthur , Brandes Elke , Keitel Claudia , Boda Sonja , Kayler Zachary E. , Granier André , Barbour Margaret , Farquhar Graham D. , Treydte Kerstin
Published: June 2013

The oxygen stable isotope composition of plant organic matter (OM) (particularly of wood and cellulose in the tree ring archive) is valuable in studies of plant–climate interaction, but there is a lack of information on the transfer of the isotope signal from the leaf to heterotrophic tissues.

We studied the oxygen isotopic composition and its enrichment above source water of leaf water over diel courses in five tree species covering a broad range of life forms. We tracked the transfer of the isotopic signal to leaf water‐soluble OM and further to phloem‐transported OM.

Observed leaf water evaporative enrichment was consistent with values predicted from mechanistic models taking into account nonsteady‐state conditions. While leaf water‐soluble OM showed the expected 18O enrichment in all species, phloem sugars were less enriched than expected from leaf water enrichment in Scots pine (Pinus sylvestris), European larch (Larix decidua) and Alpine ash (Eucalyptus delegatensis).

Oxygen atom exchange with nonenriched water during phloem loading and transport, as well as a significant contribution of assimilates from bark photosynthesis, can explain these phloem 18O enrichment patterns. Our results indicate species‐specific uncoupling between the leaf water and the OM oxygen isotope signal, which is important for the interpretation of tree ring data.
Utility of Mapping Signals to Improve Precision of Atrioventricular Node Ablation
Authors: YEO WEE TIONG , SPORTON SIMON C.E. , DHINOJA MEHUL , SCHILLING RICHARD J. , EARLEY MARK J.
Published: June 2013

Background

Atrioventricular node (AVN) ablation is effective for rate control in atrial fibrillation. This may require multiple radiofrequency applications to achieve complete atrioventricular block (CAB). In this retrospective study, we tested the hypothesis that mapping the AVN utilizing electrograms (EGMs) on both proximal and distal bipoles of the mapping catheter may improve the likelihood of CAB.

Methods

Lesion characteristics and EGM components on the proximal and distal bipoles of the ablation catheter in first‐time AVN ablation procedures were analyzed. Outcomes of each lesion, including presence of CAB, acute recurrence of AVN conduction, new‐onset right bundle branch block (RBBB), and junctional escape rhythm, were analyzed. Multivariate binary logistic regression analysis was performed to identify EGM characteristics that independently predicted the outcomes of interest. Lesions with these EGM characteristics were then identified and their outcomes compared with the whole cohort.

Results

A total of 441 ablation lesions were analyzed. EGM characteristics that independently predicted outcomes were the presence of His and atrial EGMs on the distal bipole and the absence of ventricular EGM on the proximal bipole. Among the 25 lesions with all these characteristics, 18 (72%) resulted in CAB compared to the overall cohort rate of 38% (P = 0.001). There was no new‐onset RBBB. The likelihood of acute recurrent AVN conduction and junctional escape rhythm were similar.

Conclusion

Combining proximal and distal bipole EGM characteristics of the ablation catheter can improve the accuracy of AVN localization during AVN ablation and avoid right bundle branch injury.
The Systolic Index: A Noninvasive Approach for the Assessment of Cardiac Function: Implications for Patients with DDD and CRT Devices
Authors: CHIRIFE RAUL , RUIZ G. AURORA , GAYET ENRIQUE , MURATORE CLAUDIO , MAZZETTI HÉCTOR , PELLEGRINI ALEJANDRO , TENTORI M. CRISTINA
Published: June 2013

Background

Our objective was to evaluate the systolic index (SI), the ratio between rate‐corrected left ventricular ejection time (LVETc), and a preejection period surrogate (PEPsu), to assess cardiac function in patients with DDD and cardiac resynchronization therapy (CRT) pacemakers.

Methods

LVETc and PEPsu were automatically measured from electrocardiogram and finger photoplethismography. Atrioventricular (AV) and mode switch (CRT to DDD) were used as hemodynamic challenges. Performance of SI, beat‐by‐beat systolic blood pressure (SBP), and Doppler aortic velocity/time integral (AoVTI) were compared in 36 patients, and SI's detection of CRT to DDD mode switch in nine patients, responders to CRT. AVs were changed from 30 ms to 250 ms (20 ms steps) at constant paced heart rate, alternating with a reference AV (RefAV), to reduce hemodynamic drift. The coefficient of variation (standard deviation/mean) of SI, SBP, and AoVTI during all RefAVs were used as error marker. The percentage detection of hemodynamic changes during AV transitions was a marker of sensitivity.

Results

Fifty‐five patients (males 62%, age 69.6 ± 17) were studied. SI detected 441 of 544 transitions (81%) versus 361 (66%) of SBP (P = 0.005). Error during RefAVs was smaller for SI (3.4%) as compared to AoVTI (7.8%, P = 0.015) and to SBP (5.7%, P = 0.005). SIs correlated with AoVTI (R from 0.71 to 0.98, all P < 0.001). SI detected all CRT to DDD changes (P < 0.001).

Conclusion

The noninvasive SI obtained with a simple, observer‐independent hemodynamic assessment procedure has higher accuracy than SBP and AoVTI and better sensitivity than SBP. It detects mechanical resynchronization in CRT and allows programming a suitable AV delay.
Cutting‐edge research or cutting‐edge artefact? An overdue control experiment complicates the xylem refilling story
Authors: SPERRY JOHN
Published: June 2013

This article comments on: Cutting xylem under tension or supersaturated with gas can generate PLC and the appearance of rapid recovery from embolism
The interaction between glucose and cytokinin signal transduction pathway in Arabidopsis thaliana
Authors: KUSHWAH SUNITA , LAXMI ASHVERYA
Published: June 2013

Cytokinins (CKs) and glucose (GLC) control a number of common responses in plants. We hypothesize that there may be an extensive overlap between CK‐ and GLC‐signalling pathways. Microarray along with physiological analysis has been performed to find out the interdependence/overlap between CK and GLC signal transduction pathways in Arabidopsis seedlings. GLC could transcriptionally affect 76% of CK‐regulated genes at whole genome level, 89% of which are agonistically regulated. GLC may also affect CK‐regulated gene expression via non‐transcriptional pathways. GLC can regulate several genes involved in CK metabolism and signalling. A number of gene families involved in development and stress are commonly regulated by CK and GLC. Physiologically, both GLC and CK could regulate hypocotyl length in dark. GLC and CK signalling may integrate at the level of type A Arabidopsis response regulators (ARRs) in controlling hypocotyl length. Both GLC and CK signalling cannot alter hypocotyl length in dark in auxin‐signalling mutants AUXIN RESPONSE2/INDOLE‐3‐ACETIC ACID7 (AXR2/IAA7) and AXR3/IAA17 suggesting that they may involve auxin‐signalling component as a nodal point. Here, we demonstrate that there is an extensive overlap between CK‐ and GLC‐regulated gene expression and physiological responses.
Juvenile fibromyalgia: Guidance for management
Authors: Yokota Shumpei , Kikuchi Masako , Miyamae Takako
Published: June 2013

Juvenile fibromyalgia (JFM) is a disease in which patients complain of acute and chronic severe pain, an overt primary cause for which cannot be found or surmised. Although patients with JFM mainly complain of systemic pain or allodynia in the medical interview and physical examination, the concept of the disease is the total sum of painful illness, chronic fatigue, hypothermia and many other autonomic symptoms and signs. Many issues are interacting including individual traits (personality, temperament, sensitivity, memory of pain; age: early adolescence), individual states (self‐esteem, anxiety, developmental level), and external stressors (parent especially mother, school environment). JFM is diagnosed on the combination of disease history, physical examination to determine the 18 tender points and allodynia, pain from gently touching their hair, and negative results of blood tests (inflammatory markers, thyroid function, myogenic enzymes). The goals of treatment are the following: restoration of function and relief of pain. Psychological support is advocated. Although the exact number of patients with JFM is still to be elucidated, it seems to be growing because pediatric rheumatologists in Japan encounter children with a wide variety of musculoskeletal pains. This guideline describes how to diagnose JFM in children and how to treat them appropriately.
Outcome evaluations in group decision making using the majority rule: An electrophysiological study
Authors: Kimura Kenta , Katayama Jun'ichi
Published: June 2013

Event‐related brain potential (ERP) reflecting outcome evaluation is called feedback‐related negativity (FRN). The present study examined the evaluative processes for two different types of outcomes by recording ERPs from three participants during a group decision task. First, we examined the evaluative processing of outcomes associated with group decisions using the majority rule. Second, we investigated whether the majority rule influenced the evaluation of conflicts related to individual opinions among group members. We found that FRN for monetary loss associated with the group decision was reduced when the participant's opinion was in the minority. In addition, conflict of opinions among group members elicited FRN‐like negativity, and greater amplitudes were observed when the participant's opinion was in the minority. The present results suggested that the majority rule can modulate outcome evaluations in group decision making.
Development of a severity of illness scoring system (inpatient triage, assessment and treatment) for resource‐constrained hospitals in developing countries
Authors: Olson Dan , Davis Nicole L. , Milazi Robert , Lufesi Norman , Miller William C. , Preidis Geoffrey A. , Hosseinipour Mina C. , McCollum Eric D.
Published: June 2013

Objective

To develop a new paediatric illness severity score, called inpatient triage, assessment and treatment (ITAT), for resource‐limited settings to identify hospitalised patients at highest risk of death and facilitate urgent clinical re‐evaluation.

Methods

We performed a nested case–control study at a Malawian referral hospital. The ITAT score was derived from four equally weighted variables, yielding a cumulative score between 0 and 8. Variables included oxygen saturation, temperature, and age‐adjusted heart and respiratory rates. We compared the ITAT score between cases (deaths) and controls (discharges) in predicting death within 2 days. Our analysis includes predictive statistics, bivariable and multivariable logistic regression, and calculation of data‐driven scores.

Results

A total of 54 cases and 161 controls were included in the analysis. The area under the receiver operating characteristic curve was 0.76. At an ITAT cut‐off of 4, the sensitivity, specificity and likelihood ratio were 0.44, 0.86 and 1.70, respectively. A cumulative ITAT score of 4 or higher was associated with increased odds of death (OR 4.80; 95% CI 2.39–9.64). A score of 2 for all individual vital signs was a statistically significant independent predictor of death.

Conclusions

We developed an inpatient triage tool (ITAT) appropriate for resource‐constrained hospitals that identifies high‐risk children after hospital admission. Further research is needed to study how best to operationalise ITAT in developing countries.
Donor body mass index is an important factor that affects peripheral blood progenitor cell yield in healthy donors after mobilization with granulocyte–colony‐stimulating factor
Authors: Chen Jian , Burns Kevin M. , Babic Aleksandar , Carrum George , Kennedy Martha , Segura Francisco J. , Garcia Salvador , Potts Sandra , Leveque Christopher
Published: June 2013

Background

The use of hematopoietic progenitor cell (HPC) transplantation has rapidly expanded in recent years. Currently, several sources of HPCs are available for transplantation including peripheral blood HPCs (PBPCs), cord blood cells, and marrow cells. Of these, PBPC collection has become the major source of HPCs. An important variable in PBPC collection is the response to PBPC mobilization, which varies significantly and sometime causes mobilization failure.

Study Design and Methods

A retrospective study of 69 healthy donors who underwent PBPC donation by leukapheresis was performed. All of these donors received 10 μg/kg/day or more granulocyte–colony‐stimulating factor (G‐CSF) for 5 days before PBPC harvest. Donor factors were evaluated and correlated with mobilization responses, as indicated by the precollection CD34 count (pre‐CD34).

Results

Donors with a pre‐CD34 of more than 100 × 106/L had higher body mass index (BMI) compared with donors whose pre‐CD34 was 38 × 106 to 99 × 106/L or less than 38 × 106/L (32.0 ± 1.04 kg/m2 vs. 28.7 ± 0.93 kg/m2 vs. 25.9 ± 1.27 kg/m2, respectively; p < 0.05). In addition, donors with high BMIs had higher pre‐CD34 on a per‐kilogram‐of‐body‐weight basis compared with donors with low BMIs.

Conclusion

BMI is an important factor that affects donor's response to mobilization and consequently the HPC yield. This effect may be due to a relatively high dose of G‐CSF administered to donors with higher BMI or due to the presence of unknown intrinsic factors affecting mobilization that correlate with the amount of adipose tissue in each donor.
Analysis of inventory strategies for blood components in a regional blood center using process simulation
Authors: Baesler Felipe , Nemeth Matías , Martínez Cristina , Bastías Alfonso
Published: June 2013

Background

The storage of blood components is an important concern in the blood supply chain. Because these are perishable products, the definition of good inventory policies is crucial to reduce shortages and spills.

Study Design and Methods

To analyze and propose inventory policies in a regional blood center, a discrete event simulation model was created using simulation software (Arena 12.0, Rockwell Software). The model replicates the activities that are performed along the supply chain including donation arrivals, testing, production, inventory management, and dispatching.

Results

Twelve different scenarios were analyzed, with each one representing different inventory policies composed of a combination of an optimal inventory, a reorder point, and a level of extra donations. The best scenario demonstrates that it is possible to decrease unsatisfied demand and wastage of red blood cell units by 2.5 and 3%, respectively, when compared to current practices.

Conclusions

This study shows that simulation is an alternative that can be used to model inventory components in blood centers. A responsible selection of inventory variables can improve the capability of the system to respond to the final patient requirements.
The radiosensitizing effect of the aurora kinase inhibitors, ENMD‐2076, on canine mast cell tumours in vitro
Authors: Shiomitsu K. , Sajo E. , Rubin C. , Sehgal I.
Published: June 2013

ENMD‐2076 is an aurora kinase inhibitor that also has multi‐target tyrosine kinase inhibitor properties. In this study, the mRNA and the protein expression of aurora‐A and aurora‐B were evaluated in three canine mast cell tumour cell lines. Dose‐dependent cytotoxicity was seen in the cells treated, and it affected the cell cycle with cells in the G2/M phase being selectively killed. The cells were also evaluated for radiosensitivity with/without ENMD‐2076, and radiosensitization was seen after 3 Gy and 6 Gy exposures with ENMD‐2076 for 48 h. Protein expression of caspase‐3 was gradually increased, and the expression intensity was highest at 24 h post irradiation in cells without ENMD‐2076 treatment, which indicates that radiation exposure with ENMD‐2076‐induced cell death faster than radiation treatment alone. Our study results suggest the potential usefulness of treating canine mast cell tumours with aurora kinase inhibitors alone or in conjunction with radiation therapy.
Structural Performance and Ductility of Fiber Reinforced Polymer Concrete Bonding System Under Tropical Climates
Authors: Mohd. Hashim Mohd Hisbany Mohd.Hashim , Mohd. Sam Abdul Rahman , Hussin Mohd Warid , Mohd. Arshad Mohd Fadzil
Published: June 2013

Tropical climate combines with saltwater exposure may influence the structural performance and durability of FRP–epoxy–concrete system over long period of time. FRP being non–corrodible material has been proven to be efficient materials in rehabilitation jobs compared to steel. Reinforced concrete structures may be required to be strengthened at a later age of their service life to overcome additional loading capacity and deterioration due to environmental effect. The main objective of the current paper is to study flexural behavior of an externally bonded reinforced concrete beams using carbon FRP plate and fabrics due to exposure to natural tropical climate. The research studies the ability of reinforced concrete beams externally bonded with CFRP plate and fabrics to resist numerous environmental conditions such as tropical weather, normal laboratory environment and saltwater solution. The bonded beams are subjected experimental evaluation by performing four points load test until failure to observe the failure loads, deflection, strain, cracking behavior and the patterns of failure. Strengthening of reinforced concrete beams using CFRP plate and fabrics demonstrated significant improvement in the flexural capacity of the beams by 30% and 16%, respectively compare to control specimen without strengthening.
Laboratory Measurement of Displacement on Shallow Foundation in Uniform Sand using Particle Image Velocimetry Technique
Authors: Taib Siti Noor Linda , Hung Lau See , Kolay Prabir Kumar
Published: June 2013

Particle Image Velocimetry (PIV) is one of the non–intrusive techniques recently being utilized for measuring soil displacement in geotechnical engineering. The work discussed in this paper focuses on the application of an image processing tool known as MatPIV, a freeware readily available to the general users. The test programmes involved measurement and visualization of the behavior of displaced soil under various type of loadings and sizes of the foundation plate. Prior to testing, validation test was performed to study on the validity of measurements produced by MatPIV by comparing its measurements with the actual. Boundary analysis was also performed to justify on the configuration chosen for the model box used in both validation and experimental set-ups. In addition, a set of 70 displacement data was also studied in the validation test and a further statistical analysis on the data showed an acceptable accuracy of 98.8% for the MatPIV analysis when compared to the actual measured displacement. Hence, further test programmes which consisted of various soil–structure interaction conditions were performed. This comprehensive analysis showed that the diameter of loading rods and the sizes of foundation plate do affect the behavior of soil displacement under centric structural loading and was shown successfully via MatPIV.
Behavior of Eccentrically Loaded Plain and Steel Fiber Reinforced Concrete Filled Steel Box Columns
Authors: Eltobgy Hanan Hussien , Shaaban Ibrahim Galal
Published: June 2013

The present study investigates the behavior of steel fiber reinforced concrete filled steel box columns (SFRCFSBC) targeting to enhance their strength. A nonlinear finite element model using ANSYS program has been developed to investigate the structural behavior of the inspected columns. The results obtained from that model has been compared with those calculated using Euro code (EC4), AISC/LRFD (2005) and the Egyptian Code of Practice for Steel Construction (ECPSC/LRFD 2007). The comparison indicated that the results of the model have been evaluated to an acceptable limit of accuracy. A parametric study was carried out to investigate the effect of wall thickness, column slenderness and percentage of steel fiber in concrete on the ultimate strength of composite columns. Confinement of the concrete core provided by the steel case was also investigated. It can be concluded from the results that a considerable increase in compressive and flexural strength may be gained by increasing the steel fiber percentage up to 4%. The highest rate of increase in strength for long columns was about 20% by using steel fiber percentage between 0.5% and 1.0%, while for short and medium columns was about 10% by using steel fiber percentage between 1% and 2%.
PENAMBAHBAIKAN PRESTASI FLEKSIBILITI DAN KECEKAPAN MASA BAGI SYARIKAT PEMBUATAN: SATU KAJIAN SIMULASIPENAMBAHBAIKAN PRESTASI FLEKSIBILITI DAN KECEKAPAN MASA BAGI SYARIKAT PEMBUATAN: SATU KAJIAN SIMULASI
Authors: Ab Rahman Mohd Nizam , Wan Mahmood Wan Hasrulnizzam , Md Deros Baba
Published: June 2013

Kertas kerja ini merupakan satu laporan kajian simulasi yang dijalankan untuk menambahbaik prestasi fleksibiliti dan kecekapan masa bagi syarikat pembuatan. Sebuah syarikat pembuatan aero komposit dipilih sebagai syarikat kajian kes. Daripada dua analisis simulasi yang menggunakan perisian ARENA, didapati kedua-dua prestasi iaitu fleksibiliti dan kecekapan masa berpotensi meningkatkan produktiviti serta mengurangkan kos. Ia juga membuktikan kecekapan pengurusan sumber secara fleksibel termasuk logistik dapat membantu meningkatkan penambahbaikan produktiviti syarikat. Kajian ini mendapati simulasi berkomputer dapat memberikan individu atau kumpulan kerja untuk menilai alternatif penambahbaikan secara lebih efektif.
Improving Gas Bubbles’ Half Life in Foam Drilling Fluid
Authors: Ismail Issham , Mamat Nur Suriani , Mamat Baihaqi , Ismail Ahmad Shamsulizwan , Kamis Azmi , Ikhsan Azman
Published: June 2013

An underbalanced drilling using foam drilling fluid is one of the most effective solutions which are capable of preventing formation damage, differential sticking, or circulation lost. Nevertheless, the limitation of using foam drilling fluid is the stability of its rheological properties which would affect its lubricity characteristics. Therefore, a research study was carried out to determine the stability and effectiveness of water soluble polymers as an additive in foam drilling fluid. To produce the required and most stable foam, four types of surfactants had been tested, namely sodium dodecyl sulfate (anionic), cetyltrimethylammonium bromide (cationic), T×100 (non ionic), and n-alkyl betaines (amphoteric). Then, the water soluble polymers, namely xanthan gum, hydroxyethyl cellulose, guar gum, and carboxymethyl cellulose, were evaluated as a stabilizer in the said foam drilling fluid. The laboratory works involved lubricity and rheological properties tests, which were conducted at ambient condition. The experimental results showed that the use of xanthan gum with anionic surfactant produced the most stable foam drilling fluid compared to other polymers. Rheological properties of the polymer foam drilling fluid were compared with water-based mud, and it was revealed that polymer foam drilling fluid could perform as effective as the latter. The significant advantage of using polymer foam drilling fluid was its coefficient of friction which was found to be lower than the water-based mud.
The Effect of Virgin Coconut Oil Loaded Solid Lipid Particles (VCO-SLPs) on Skin Hydration and Skin Elasticity
Authors: Noor Norhayati Mohamed
Published: June 2013

Virgin Coconut Oil is oil extracted from well matured and fresh coconut through specialized processes without damaging its natural nutrition. In this work virgin coconut oil is loaded into solid lipid microparticles to be used in a moisturizer formulation. The virgin coconut oil loaded solid lipid microparticles were prepared using ultrasonification of molten stearic acid and virgin coconut oil in an aqueous solution and microparticles with the size of 0.608 µm have been obtained. 20% concentration of VCO-SLPs of 0.608 µm particle size was added into the base lotion. Sensory study and skin evaluation study was conducted to compare the difference between lotion containing VCO-SLPs and lotion without VCO-SLPs. Moisturizer incorporated with 20% VCO-SLPs was found to be the best effective as a moisturizer compared to the placebo lotion.
Understanding Environmental Audit in the Public Sector: Malaysian Perspective
Authors: Yusoff Hairul Nizam
Published: June 2013

Environmental audit is considered a new approach and still in the evolving process. This situation has significant influence on the efforts to provide a single interpretation to be accepted by the public. Most of the definitions offered by organizations normally influenced by the nature of the organizations' operations and in general the private practices play a leading role in providing the definitions compared to the public sector. In the context of environmental audit in the public sector, definition about the audit is referred to the framework provided by the INTOSAI as the main reference to the auditors. Due to its various definitions, this study is conducted to look at how this perspective influences understanding of the public sector auditors in particular in the developing countries as the case of Malaysia. This study employed qualitative approach where interviews were conducted with selected auditors to gain their understanding about environmental audit. The result showed consistent understanding by the auditors with the established framework for environmental auditing in the public sector. Even though there were some gaps between respondents' opinion and the framework, but the framework eventually served as a fundamental for the auditors to understand about environmental audit.
Experimental Study On Premixed Flame Acceleration In Closed Pipe
Authors: Mat Kiah M. H. , Kasmani R. M.
Published: June 2013

An experimental study has been carried out to investigate the flame acceleration in closed pipe. A horizontal steel pipe, with 2 m long and 0.1 m diameter, giving L/D ratio of 20 was used in this project. For test with 90 degree bends, the bend has a radius of 0.1 m and added a further 1 m to the length of the pipe (based on the centerline length of the segment). Ignition was affected at one end of the vessel while the other end was closed. Natural gas/oxygen mixtures were studied with equivalence ratio, Ф ranges from 0.5 to 1.8. It was demonstrated that bending pipe gave three times higher in overpressure (5.5 bars) compared to 2.0 bars of straight pipe. It is also shown that the flame speed is 63 m s-1, greater by factor of ~ 3 for explosion in bending pipe in comparison with straight pipe (23 m s-1). This is due to bending acting similar to obstacles. This mechanism could induce and create more turbulence, initiating the combustion of unburned pocket at the corner region, causing high mass burning rate and hence, increasing the flame speed.
Perbandingan Kompetensi Pengetua Sekolah antara Malaysia dan Indonesia
Authors: Mustamin Mustamin , Hj. Mohd. Yasin M. Al Muzzammil
Published: June 2013

Cabaran pendidikan pada masa ini semakin membimbangkan pengetua sekolah yang tidak mempunyai kompetensi sebagai pemimpin pendidikan. Kompetensi sebagai pemimpin pendidikan dalam kajian ini ialah kompetensi dari segi kepimpinan sekolah, kepimpinan pengajaran dan kepimpinan operasional sekolah yang merupakan hasil penggabungjalinan dokumen kompetensi kepengetuaan sekolah khasnya dokumen Malaysia dan Indonesia. Sebanyak 81 responden daripada 22 SMK di Johor, Malaysia dan 154 responden daripada 40 SMA Negeri Provinsi Sulawesi Selatan, Indonesia menyertai kajian ini. Kaedah analisis yang digunakan iaitu; Analisis Faktor (Exploratory Factor Analysis-EFA, dan Confirmatory Factor Analysis-CFA), analisis deskriptif dan analisis inferensial. Dapatan analisis EFA dan CFA menunjukkan bahawa dimensi-dimensi kompetensi yang digunakan dalam kajian ini amnya menyokong secara signifikan terhadap faktor kompetensi yang dibincangkan. Manakala dapatan deskriptif menunjukkan bahawa tahap kompetensi pengetua sekolah di Malaysia pada amnya lebih tinggi berbanding kompetensi pengetua sekolah di Indonesia. Seterusnya, keputusan analisis hipotesis menunjukkan menolak hipotesis nul yang dicadangkan, yang bermakna bahawa terdapat perbezaan yang signifikan antara kompetensi pengetua sekolah di Malaysia dan Indonesia.
Characteristics of Deposits in Gas Turbine Combustion Chambers Using Synthetic and Conventional Jet Fuels
Authors: Pucher Greg , Allan William , Poitras Pierre
Published: June 2013

The synthetic fuel industry is poised to experience large-scale growth and profoundly affect current aviation fuel infrastructure. New candidate technologies, such as Camelina oil-derived synthetic fuel have been demonstrated to not only provide satisfactory quasi drop-in characteristics for conventional fuels, but in life cycle analysis studies have also been shown to potentially offer positive improvements relative to conventional feedstocks with respect to economic, environmental, and land use considerations. As part of a multiyear study at the Royal Military College of Canada to evaluate combustion related parameters of fuel additives and alternative fuels for gas turbine applications, a Camelina-derived synthetic fuel blend was assessed to determine potential combustion related benefits as compared to conventional and other synthetic blends. The Combustion Chamber Sector Rig (CCSR) which houses a Rolls Royce T-56-A-15 combustion section was utilized for the evaluation of emissions and deposits. Following combustion testing, several combustion system components, including the combustion chamber, fuel nozzle, and igniter plug were analyzed for relative levels of deposit build-up. As with other Fischer Tropsch derived synthetic fuels, there were positive benefits found with Camelina blends in terms of emissions performance and deposit production tendencies.
Lessons Learned From the Development of Courses on Gas Turbine Multidisciplinary Conceptual Design
Authors: Kyprianidis Konstantinos G. , Grönstedt Tomas , Barbosa João R.
Published: June 2013

Despite the need for highly qualified experts, multidisciplinary gas turbine conceptual design has not been a common study topic in traditional postgraduate curriculums. Although many courses on specialized topics in gas turbine technology take place, limited attention is given on connecting these individual topics to the overall engine design process. Teaching conceptual design as part of a postgraduate curriculum, or as an intensive short course, may help to address the industrial need for engineers with early qualifications on the topic, i.e., prior to starting their careers in the gas turbine industry. This paper presents details and lessons learned from: (i) the integration of different elements of conceptual design in an existing traditional Master of Science (MSc) course on gas turbine technology through the introduction of group design tasks and (ii) the development of an intensive course on gas turbine multidisciplinary conceptual design as a result of an international cooperation between academia and industry. Within the latter course, the students were grouped in competing teams and were asked to produce their own gas turbine conceptual design proposals within a given set of functional requirements. The main concept behind the development of the new design tasks, and the new intensive course, has been to effectively mimic the dynamics of small conceptual design teams, as often encountered in industry. The results presented are very encouraging in terms of enhancing student learning and developing engineering skills.
Boiling Heat Transfer and Critical Heat Flux Enhancement of Upward- and Downward-Facing Heater in Nanofluids
Authors: Zuhairi Sulaiman Muhamad , Takamura Masahiro , Nakahashi Kazuki , Okawa Tomio
Published: June 2013

Boiling heat transfer (BHT) and critical heat flux (CHF) performance were experimentally studied for saturated pool boiling of water-based nanofluids. In present experimental works, copper heaters of 20 mm diameter with titanium-oxide (TiO2) nanocoated surface were produced in pool boiling of nanofluid. Experiments were performed in both upward and downward facing nanofluid coated heater surface. TiO2 nanoparticle was used with concentration ranging from 0.004 until 0.4 kg/m3 and boiling time of tb = 1, 3, 10, 20, 40, and 60 mins. Distilled water was used to observed BHT and CHF performance of different nanofluids boiling time and concentration configurations. Nucleate boiling heat transfer observed to deteriorate in upward facing heater, however; in contrast effect of enhancement for downward. Maximum enhancements of CHF for upward- and downward-facing heater are 2.1 and 1.9 times, respectively. Reduction of mean contact angle demonstrate enhancement on the critical heat flux for both upward-facing and downward-facing heater configuration. However, nucleate boiling heat transfer shows inconsistency in similar concentration with sequence of boiling time. For both downward- and upward-facing nanocoated heater's BHT and CHF, the optimum configuration denotes by C = 400 kg/m3 with tb = 1 min which shows the best increment of boiling curve trend with lowest wall superheat ΔT = 25 K and critical heat flux enhancement of 2.02 times.
Simulation of an Intake Manifold Preheater for Cold Engine Startup
Authors: Kreun Patrick K. , Fajardo Claudia M. , Baumann Andreas
Published: June 2013

Ensuring consistent, reliable diesel engine startups in cold temperatures is of utmost importance in a number of applications. Under extreme temperatures, the use of glow plugs is complemented by intake manifold heaters. In these, the energy released from combustion increases the intake air temperature before the air enters the main combustion chamber. Since the process also alters the stoichiometry of the fuel-air mixture at the intake ports, the preheater operation must be optimized in order to guarantee successful and reliable in-cylinder combustion during engine startups. This paper describes the development of an intake manifold model incorporating an air preheater for application in a diesel engine. The model was created using a commercial, one-dimensional simulation tool and its default heat transfer model was modified in-house for the present application. The model was validated against experimental data and subsequently used to quantify the concentration of combustion product species at the intake runners, as well as intake charge dilution. The experimental and predicted intake runner gas temperatures agreed within 15%. Results showed that the effective equivalence ratio might increase up to 2.6 after the first 15 s of cranking, with 12.5% reduction of the O2 concentration in the intake charge.
Effects of Advanced Engine Technology on Open Rotor Cycle Selection and Performance
Authors: Perullo Christopher A. , Tai Jimmy C. M. , Mavris Dimitri N.
Published: June 2013

Recent increases in fuel prices and increased focus on aviation's environmental impacts have reignited focus on the open rotor engine concept. This type of architecture was extensively investigated in previous decades but was not pursued through to commercialization due to relatively high noise levels and a sudden, sharp decrease in fuel prices. More recent increases in fuel prices and increased government pressure from taxing carbon-dioxide production mean the open rotor is once again being investigated as a viable concept. Advances in aero-acoustic design tools have allowed industry and academia to re-investigate the open rotor with an increased emphasis on noise reduction while retaining the fuel burn benefits due to the increased propulsive efficiency. Recent research with conceptual level multidisciplinary considerations of the open rotor has been performed (Bellocq et al., 2010, “Advanced Open Rotor Performance Modeling For Multidisciplinary Optimization Assessments,” Paper No. GT2010-2963), but there remains a need for a holistic approach that includes the coupled effects of the engine and airframe on fuel burn, emissions, and noise. Years of research at Georgia Institute of Technology have led to the development of the Environmental Design Space (EDS) (Kirby and Mavris, 2008, “The Environmental Design Space,” Proceedings of the 26th International Congress of the Aeronautical Sciences). EDS serves to capture interdependencies at the conceptual design level of fuel burn, emissions, and noise for conventional and advanced engine and airframe architectures. Recently, leveraging NASA environmentally responsible aviation (ERA) modeling efforts, EDS has been updated to include an open rotor model to capture, in an integrated fashion, the effects of an open rotor on conventional airframe designs. Due to the object oriented nature of EDS, the focus has been on designing modular elements that can be updated as research progresses. A power management scheme has also been developed with the future capability to trade between fuel efficiency and noise using the variable pitch propeller system. Since the original GE open rotor test was performed using a military core, there is interest in seeing the effect of modern core-engine technology on the integrated open rotor performance. This research applies the modular EDS open rotor model in an engine cycle study to investigate the sensitivity of thermal efficiency improvements on open rotor performance, including the effects on weight and vehicle performance. The results are that advances in the core cycle are necessary to enable future bypass ratio growth and the trades between core operating temperatures and size become more significant as bypass ratio continues to increase. A general benefit of a 30% reduction in block fuel is seen on a 737-800 sized aircraft.
Low Temperature Combustion Optimization and Cycle-by-Cycle Variability Through Injection Optimization and Gas-to-Liquid Fuel-Blend Ratio
Authors: Michailidis A. D. , Stobart R. K. , McTaggart-Cowan G. P.
Published: June 2013

The advent of common rail technology alongside powerful control systems capable of delivering multiple accurate fuel charges during a single engine cycle has revolutionized the level of control possible in diesel combustion. This technology has opened a new path enabling low-temperature combustion (LTC) to become a viable combustion strategy. The aim of the research work presented within this paper is the understanding of how various engine parameters of LTC optimize the combustion both in terms of emissions and in terms of fuel efficiency. The work continues with an investigation of in-cylinder pressure and IMEP cycle-by-cycle variation. Attention will be given to how repeatability changes throughout the combustion cycle, identifying which parts within the cycle are least likely to follow the mean trend and why. Experiments were conducted on a single-cylinder 510cc boosted diesel engine. LTC was affected over varying rail pressure and combustion phasing. Single and split injection regimes of varying dwell-times were investigated. All injection conditions were phased across several crank-angles to demonstrate the interaction between emissions and efficiency. These tests were then repeated with blends of 30% and 50% gas-to-liquid (GTL)-diesel blends in order to determine whether there is any change in the trends of repeatability and variance with increasing GTL blend ratio. The experiments were evaluated in terms of emissions, fuel efficiency, and cyclic behavior. Specific attention was given to how the NOx–PM trade-off changes through increased injection complexity and increasing GTL blend ratio. The cyclic behavior was analyzed in terms of in-cylinder pressure standard deviation. This gives a behavior profile of the repeatability of in-cylinder pressure in comparison to the mean. Each condition was then compared to the behavior of equivalent injection conditions in conventional diesel combustion. Short-dwell split injection was shown to be beneficial for LTC, while NOx was shown to be reduced by the substitution of GTL in the fuel. In-cylinder pressure cyclic behavior was also shown to be comparable or superior to conventional combustion in every case examined. GTL improved this further, but not in proportion to its blend ratio.
Extraction of otoacoustic distortion product sources using pulse basis functions
Authors: Zelle Dennis , Gummer Anthony W. , Dalhoff Ernst
Published: June 2013

Distortion product otoacoustic emissions (DPOAEs) acquired in normal-hearing subjects show considerable variation in amplitude with varying frequency. This is known as DPOAE fine structure. It is widely accepted that fine structure results from wave interference from two DPOAE sources, a non-linear generation component and a coherent reflection component. Here a method is presented that decomposes short-pulse DPOAE recordings into pulse basis functions and enables the quantification of both source components in the time domain, independent of their relative phase and at low cost of measurement time. Input-output functions utilizing the extracted primary-source component are analyzed.
Epistasis Among Adaptive Mutations in Deer Mouse Hemoglobin
Authors: Natarajan Chandrasekhar , Inoguchi Noriko , Weber Roy E. , Fago Angela , Moriyama Hideaki , Storz Jay F.
Published: June 2013

Holding Your Breath

Hemoglobin and myoglobin are widely responsible for oxygen transport and storage (see the Perspective by

Rezende

). The ability of diving mammals to obtain enough oxygen to support extended dives and foraging is largely dependent on muscle myoglobin (Mb) content.

Mirceta
et al.

(p.
1303
) found that in mammalian lineages with an aquatic or semiaquatic lifestyle, Mb net charge increases, which may represent an adaptation to inhibit self-association of Mb at high intracellular concentrations. Epistasis results from nonadditive genetic interactions and can affect phenotypic evolution.

Natarajan
et al.

(p.
1324
) found that epistatic interactions were able to explain the increased hemoglobin oxygen-binding affinity observed in deer mice populations at high altitude. In mammals, the offloading of oxygen from hemoglobin is facilitated by a reduction in the blood's pH, driven by metabolically produced CO
2
. However, in fish, a reduction in blood pH reduces oxygen carrying capacity of hemoglobin.

Rummer
et al.

(p.
1327
) implanted fiber optic oxygen sensors within the muscles of rainbow trout and found that elevated CO
2
levels in the water led to acidosis and elevated oxygen tensions.