bluuebunny/crossref_metadata_2025 huggingface dataset:
Forecasting pollination declines through DNA barcoding: the potential contributions of macroecological and macroevolutionary scales of inquiry
Authors: Vamosi Jana C. , Gong Yan‐Bing , Adamowicz Sarah J. , Packer Laurence
Published: November 2016

While pollinators are widely acknowledged as important contributors to seed production in plant communities, we do not yet have a good understanding of the importance of pollinator specialists for this ecosystem service. Determination of the prevalence of pollinator specialists is often hindered by the occurrence of cryptic species and the limitations of observational data on pollinator visitation rates, two areas where DNA barcoding of pollinators and pollen can be useful. Further, the demonstrated adequacy of pollen DNA barcoding from historical records offers opportunities to observe the effects of pollinator loss over longer timescales, and phylogenetic approaches can elucidate the historical rates of extinction of specialist lineages. In this Viewpoint article, we review how advances in DNA barcoding and metabarcoding of plants and pollinators have brought important developments to our understanding of specialization in plant–pollinator interactions. We then put forth several lines of inquiry that we feel are especially promising for providing insight on changes in plant–pollinator interactions over space and time. Obtaining estimates of the effects of reductions in specialists will contribute to forecasting the loss of ecosystem services that will accompany the erosion of plant and pollinator diversity.
Alterations of specific lipid groups in serum of obese humans: a review
Authors: Mika A. , Sledzinski T.
Published: November 2016

Obesity is a major contributor to the dysfunction of liver, cardiac, pulmonary, endocrine and reproductive system, as well as a component of metabolic syndrome. Although development of obesity‐related disorders is associated with lipid abnormalities, most previous studies dealing with the problem in question were limited to routinely determined parameters, such as serum concentrations of triacylglycerols, total cholesterol, low‐density and high‐density lipoprotein cholesterol. Many authors postulated to extend the scope of analysed lipid compounds and to study obesity‐related alterations in other, previously non‐examined groups of lipids. Comprehensive quantitative, structural and functional analysis of specific lipid groups may result in identification of new obesity‐related alterations. The review summarizes available evidence of obesity‐related alterations in various groups of lipids and their impact on health status of obese subjects. Further, the role of diet and endogenous lipid synthesis in the development of serum lipid alterations is discussed, along with potential application of various lipid compounds as risk markers for obesity‐related comorbidities.
The impact of interventions to promote healthier ready‐to‐eat meals (to eat in, to take away or to be delivered) sold by specific food outlets open to the general public: a systematic review
Authors: Hillier‐Brown F. C. , Summerbell C. D. , Moore H. J. , Routen A. , Lake A. A. , Adams J. , White M. , Araujo‐Soares V. , Abraham C. , Adamson A. J. , Brown T. J.
Published: November 2016

Introduction

Ready‐to‐eat meals sold by food outlets that are accessible to the general public are an important target for public health intervention. We conducted a systematic review to assess the impact of such interventions.

Methods

Studies of any design and duration that included any consumer‐level or food‐outlet‐level before‐and‐after data were included.

Results

Thirty studies describing 34 interventions were categorized by type and coded against the Nuffield intervention ladder: restrict choice = trans fat law (n = 1), changing pre‐packed children's meal content (n = 1) and food outlet award schemes (n = 2); guide choice = price increases for unhealthier choices (n = 1), incentive (contingent reward) (n = 1) and price decreases for healthier choices (n = 2); enable choice = signposting (highlighting healthier/unhealthier options) (n = 10) and telemarketing (offering support for the provision of healthier options to businesses via telephone) (n = 2); and provide information = calorie labelling law (n = 12), voluntary nutrient labelling (n = 1) and personalized receipts (n = 1). Most interventions were aimed at adults in US fast food chains and assessed customer‐level outcomes. More ‘intrusive’ interventions that restricted or guided choice generally showed a positive impact on food‐outlet‐level and customer‐level outcomes. However, interventions that simply provided information or enabled choice had a negligible impact.

Conclusion

Interventions to promote healthier ready‐to‐eat meals sold by food outlets should restrict choice or guide choice through incentives/disincentives. Public health policies and practice that simply involve providing information are unlikely to be effective.
Extinction of South American sparassodontans (Metatheria): environmental fluctuations or complex ecological processes?
Authors: López‐Aguirre Camilo , Archer Michael , Hand Suzanne J. , Laffan Shawn W.
Published: November 2016

Sparassodontans are a diverse but now extinct group of metatherians that were apex predators in South America during most of the Cenozoic. Studying their decline has been controversial mainly due to the scarcity of the fossil record, and different methodological approaches have led to contradictory hypotheses. In an effort to explore questions about their extinction, we developed a novel multi‐model statistical approach to analyse all of the currently available data at a continental scale. Using multiple regression analysis and new advances in beta diversity analysis, we used all currently available fossil data at a continental scale to test four competing hypotheses to account for the decline of sparassodontans: competition with placental carnivorans, competition with avian phorusrhacids, non‐competitive ecological interactions, and environmental fluctuations. Our results show that the sparassodontan extinction was a gradual process with species disappearing throughout the Cenozoic. Multiple regression analysis supported non‐competitive ecological interactions as the best extinction model. Native South American ungulates, African migrants (caviomorph rodents and platyrrhine primates) and didelphimorphians were the groups with the highest statistical significance. Sparassodontan beta diversity increased between South American Land Mammal Ages after the Paleocene–Eocene boundary. Our results demonstrate that ecological modelling techniques illuminate aspects of extinction processes whilst mitigating the limitations of the fossil record. Our study suggests that non‐competitive ecological interactions could have been the main driver for sparassodontan extinction rather than, as commonly assumed, a result of competition and/or abiotic fluctuations.
Why Do Irrational Beliefs Mimic Science? The Cultural Evolution of Pseudoscience
Authors: Blancke Stefaan , Boudry Maarten , Pigliucci Massimo
Published: November 2016

Why do irrational beliefs adopt the trappings of science, to become what is known as “pseudoscience”? Here, we develop and extend an epidemiological framework to map the factors that explain the form and the popularity of irrational beliefs in scientific garb. These factors include the exploitation of epistemic vigilance, the misunderstanding of the authority of science, the use of the honorific title of “science” as an explicit argument for belief, and the phenomenon of epistemic negligence. We conclude by integrating the various factors in an epidemiological framework and thus provide a comprehensive cultural evolutionary account of science mimicry.
Household‐level risk factors for secondary influenza‐like illness in a rural area of Bangladesh
Authors: Weaver Anne M. , Khatun‐e‐Jannat Kaniz , Cercone Emily , Krytus Kimberly , Sohel Badrul Munir , Ahmed Makhdum , Rahman Mustafizur , Azziz‐Baumgartner Eduardo , Yu Jihnhee , Fry Alicia M. , Luby Stephen P. , Ram Pavani K.
Published: November 2016

Objective

To describe household‐level risk factors for secondary influenza‐like illness (ILI), an important public health concern in the low‐income population of Bangladesh.

Methods

Secondary analysis of control participants in a randomised controlled trial evaluating the effect of handwashing to prevent household ILI transmission. We recruited index‐case patients with ILI – fever (<5 years); fever, cough or sore throat (≥5 years) – from health facilities, collected information on household factors and conducted syndromic surveillance among household contacts for 10 days after resolution of index‐case patients’ symptoms. We evaluated the associations between household factors at baseline and secondary ILI among household contacts using negative binomial regression, accounting for clustering by household.

Results

Our sample was 1491 household contacts of 184 index‐case patients. Seventy‐one percentage reported that smoking occurred in their home, 27% shared a latrine with one other household and 36% shared a latrine with >1 other household. A total of 114 household contacts (7.6%) had symptoms of ILI during follow‐up. Smoking in the home (RRadj 1.9, 95% CI: 1.2, 3.0) and sharing a latrine with one household (RRadj 2.1, 95% CI: 1.2, 3.6) or >1 household (RRadj 3.1, 95% CI: 1.8–5.2) were independently associated with increased risk of secondary ILI.

Conclusion

Tobacco use in homes could increase respiratory illness in Bangladesh. The mechanism between use of shared latrines and household ILI transmission is not clear. It is possible that respiratory pathogens could be transmitted through faecal contact or contaminated fomites in shared latrines.
Video Gaming as Practical Accomplishment: Ethnomethodology, Conversation Analysis, and Play
Authors: Reeves Stuart , Greiffenhagen Christian , Laurier Eric
Published: November 2016

Accounts of video game play developed from an ethnomethodological and conversation analytic (EMCA) perspective remain relatively scarce. This study collects together an emerging, if scattered, body of research which focuses on the material, practical “work” of video game players. The study offers an example‐driven explication of an EMCA perspective on video game play phenomena. The materials are arranged as a “tactical zoom.” We start very much “outside” the game, beginning with a wide view of how massive‐multiplayer online games are played within dedicated gaming spaces; here, we find multiple players, machines, and many different sorts of activities going on (besides playing the game). Still remaining somewhat distanced from the play of the game itself, we then take a closer look at the players themselves by examining a notionally simpler setting involving pairs taking part in a football game at a games console. As we draw closer to the technical details of play, we narrow our focus further still to examine a player and spectator situated “at the screen” but jointly analyzing play as the player competes in an online first‐person shooter. Finally, we go “inside” the game entirely and look at the conduct of avatars on‐screen via screen recordings of a massively multiplayer online game. Having worked through specific examples, we provide an elaboration of a selection of core topics of ethnomethodology and conversation analysis that is used to situate some of the unstated orientations in the presentation of data fragments. In this way, recurrent issues raised in the fragments are shown as coherent, interconnected phenomena. In closing, we suggest caution regarding the way game play phenomena have been analyzed in this study, while remarking on challenges present for the development of further EMCA‐oriented research on video game play.
The effects of becoming taller: direct and pleiotropic effects of artificial selection on plant height in Brassica rapa
Authors: Zu Pengjuan , Schiestl Florian P.
Published: November 2016

Plant height is an important trait for plant reproductive success. Plant height is often under pollinator‐mediated selection, and has been shown to be correlated with various other traits. However, few studies have examined the evolutionary trajectory of plant height under selection and the pleiotropic effects of plant height evolution. We conducted a bi‐directional artificial selection experiment on plant height with fast cycling Brassica rapa plants to estimate its heritability and genetic correlations, and to reveal evolutionary responses to artificial selection on height and various correlated traits. With the divergent lines obtained through artificial selection, we subsequently conducted pollinator‐choice assays and investigated resource limitation of fruit production. We found that plant height variation is strongly genetically controlled (with a realized heritability of 41–59%). Thus, plant height can evolve rapidly under phenotypic selection. In addition, we found remarkable pleiotropic effects in phenology, morphology, floral scent, color, nectar and leaf glucosinolates. Most traits were increased in tall‐line plants, but flower size, UV reflection and glucosinolates were decreased, indicating potential trade‐offs. Pollinators preferred plants of the tall selection lines over the short selection lines in both greenhouse experiments with bumblebees and field experiment with natural pollinators. We did not detect any differences in resource limitation between plants of the different selection lines. Overall, our study predicts that increased height should evolve under positive pollinator‐mediated directional selection with potential trade‐offs in floral signals and herbivore defense.
DETECTION AND IDENTIFICATION OF D6 AND DUFFY ANTIGEN/RECEPTOR FOR CHEMOKINES (DARC) BY ANTIBODY BASED ASSAYS
Authors: Yee Tan Wee , Ibrahim Darah , Yin Khoo Boon , Ai Lan Chew
Published: November 2016

D6 and DARC are decoy chemokine binding receptors. They had been studied extensively in recent years for their role in breast cancer studies. The purpose of this study was to improve some critical steps in Western Blot in order to detect and identify recombinant D6 and DARC which has been expressed intracellularly by Pichia-GS115. Total proteins of Pichia-GS115 were obtained by breaking the yeast cells using acid-washed glass beads. Then, the lysates were treated with treatment buffer before electrophoresed on SDS-polyacrylamide gel. Western Blot was carried out after SDS PAGE to detect and identify the presence of recombinant D6 and DARC. Several parameters of Western Blot were studied and improved to enhance the specificity of results obtained. It was found that blocking of nitrocellulose membrane with 3% (w/v) skimmed milk at room temperature for 1 hour, incubation of primary antibody at the dilution of 1: 300 at room temperature for 16 hours and incubation of secondary antibody at the dilution of 1: 1000 at room temperature for 1 hour were able to enhance the sensitivity and specificity of Western Blot results. With the aid of prestained protein ladder as a marker, recombinant D6 and also DARC were shown as clear and precise bands at the range of molecular weight of 50-60 kDa on developed films using ECL substrate. The film exposure time was found to be 5 minutes for D6 and 10 minutes for DARC. As a result, the studies showed that improved Western Blot condition detected and identified the presence of recombinant D6 and DARC in the cell pellets of Pichia-GS115
INFLUENCE OF PROCESSING ON MECHANICAL PROPERTIES OF 3Y-TZP FOR DENTAL APPLICATIONS
Authors: Aboras Mohamed , Muchtar Andanastuti , Azhari Che Husna , Yahaya Norziha , Hao Chin Chuin
Published: November 2016

Purpose: This study aimed to investigate the influence of processing on the mechanical properties of 3 mol% yttrium–tetragonal zirconia (3Y–TZP) for dental applications. In this study, cold isostatic pressing (CIP) was adopted as a second consolidation process to enhance the mechanical properties of slip-cast 3Y–TZP. Methods: Two batches were prepared. The first batch of 3Y–TZP suspension was fabricated via colloidal processing. Then, the suspension was subjected to the slip casting process. Simultaneously, the second batch was prepared via colloidal processing, followed by CIP. The specimens were sintered at 1600 °C.  Sintered density, hardness, microstructure, and phase distribution were examined and analyzed. Results showed that the specimens fabricated via slip casting and CIP had the highest density of 99% of the theoretical density (6.1 g/cm3) and hardness of 14.4 GPa. The microstructure of the CIP samples was homogeneous with low porosity. According to X-ray diffraction examination, both batches exhibited a single phase (tetragonal phase). Conclusion(s): The density, hardness, and homogeneity of the microstructure of Y–TZP fabricated via slip casting and CIP improved. Using CIP as the second consolidation method improved the quality of green bodies
A PRELIMINARY STUDY OF RISK FACTORS OF BREAST CANCER AND THE USEFULNESS OF BREAST MRI AS AN ADDITION TO MAMMOGRAPHY IN DETECTING BREAST CANCER IN HIGH RISK WOMEN
Authors: A. Karim Noor Khairiah , Hami Rohayu , Hashim Nur Hashamimi , Azman Nizuwan , Shuaib Ibrahim Lutfi
Published: November 2016

The risk factors of breast cancer among women, such as genetic, family history and lifestyle factors, can be divided into high-, intermediate- and average-risk. Determining these risk factors may actually help in preventing breast cancer occurrence. Besides that, screening of breast cancer which include mammography, can be done in promoting early breast cancer detection. Breast magnetic resonance imaging (MRI) has been recommended as a supplemental screening tool in high risk women. The aim of this study was to identify the significant risk factor of breast cancer among women and also to determine the usefulness of breast MRI as an addition to mammography in detection of breast cancer in high risk women. This retrospective cohort study design was conducted using patients’ data taken from those who underwent mammography for screening or diagnostic purposes in Advanced Medical and Dental Institute, Universiti Sains Malaysia, from 2007 until 2015. Data from 289 subjects were successfully retrieved and analysed based on their risk factors of breast cancer. Meanwhile, data from 120 subjects who had high risks and underwent both mammography and breast MRI were further analysed. There were two significant risk factors of breast cancer seen among the study population: family history of breast cancer (p-value=0.012) and previous history of breast or ovarian cancer (p-value <0.001). Breast MRI demonstrated high sensitivity (90%) while mammography demonstrated high specificity (80%) in detection of breast cancer in all 120 subjects. The number of cases of breast cancer detection using breast MRI [46 (38.3%)] was higher compared to mammography [24 (20.0%)]. However, breast MRI was found to be non-significant as an adjunct tool to mammography in detecting breast cancer in high risk women (p-value=0.189). A comprehensive screening guideline and surveillance of women at high risk is indeed useful and should be implemented to increase cancer detection rate at early stage
PROLIFERATIVE ACTIVITY OF SAPONIN-REDUCING Carica papaya LEAVES EXTRACTS ON HUMAN LUNG FIBROBLAST CELL (IMR90)
Authors: Zainal Abidin Noraziani , Omar Hazreen , Empungan Anathasia Janam , Kamalaldin Nurulain ‘Atikah , Yahaya Badrul Hisham , Zubairi Saiful Irwan
Published: November 2016

Carica papaya belongs to Carricaceae family, which has been proven traditionally to treat dengue fever due to its pharmacological properties to increase platelet count. However, during the critical phase of dengue fever, the platelet count will decrease due to the blood vessel rupturing. Therefore, the main objectives of this study were to reduce the bitterness of Carica papaya extract by removing saponin and to study the effect of saponin-reducing extract on the proliferative activity of human lung fibroblast cell (IMR90). For preparative isolation of the saponin compound, peleg model was used to determine the maximum extract concentration, exhaustive time of extraction and total saponin content (TSC) using different weights of dry Amberlite® IRA-67 resin. The remaining saponins in the extract were quantified by mean of RP-HPLC prior to material balance. Then, approximately 1.0 x 104 cells of IMR90 were seeded onto 96-well plate and later treated with various concentrations of extracts for 3 days of incubation. The results showed that, the amount of saponin left in the extract was approximately the same as in the untreated extract (p<0.05). A short adsorption incubation time (2 hrs) was believed to affect the saponin adsorption efficiency. In fact, other bio-active constituents (e.g. polyphenolic compounds) might have been adsorbed as there was a significant depreciation of antioxidant properties on the treated extract (p<0.05). In conclusion, after three consecutively days of extracts-IMR90 cell incubation, the best EC50 values of both untreated and saponin-reducing extracts were observed to be more than 24 hrs of exposure ranging from 104.08 ± 0.90 to 17040.47 ± 2.30 µg/ml. Meanwhile, saponin-reducing extract has been proven not to affect any normal cell growth but in fact it decreased 1.2-fold as compared to the extract containing saponin (control).
SYNTHESIS AND CHARACTERISATION OF SILVER NANOPARTICLES USING VERNONIA CINEREA AQUEOUS EXTRACT AND THEIR CYTOTOXICITY ACTIVITY AGAINST KASUMI-1 CELL LINE
Authors: Mohamad Zani Radhiyatul Akma , Ahmad Nor Hazwani , Abdul Razak Siti Razila
Published: November 2016

Green synthesis is preferable for the synthesis of silver nanoparticles (AgNPs) due to its rapid and reliable process. Previous studies have demonstrated that active compounds present in Vernonia cinerea (V. cinerea) are responsible for bioreduction during synthesis of AgNPs. Hence, in this present study, aqueous extract of V. cinerea was used to synthesise AgNPs. The V. cinerea aqueous extract was added to AgNO3 solution (25 mL, 50 mL and 100 mL) to produce mixture with ratio of 1:5, 1:10 and 1:20. The formation of V. cinerea-AgNPs was monitored for colour changes, and characterised by UV-Vis spectroscopy, transmission electron microscopy (TEM) and zeta potential analyses. The UV-Vis spectrum of V. cinerea-AgNPs showed absorption maxima at 450 nm while TEM images showed that the V. cinerea-AgNPs were spherical in shape with an average size of 15.29 nm. The zeta value of synthesised V. cinerea-AgNPs was – 29.50 mV with a peak area of 100 % intensity. The cytotoxicity of V. cinerea-AgNPs were tested in vitro on Kasumi-1 cells using MTS assay. The MTS assay revealed that the V. cinerea-AgNPs with the concentration of 31.25 mg/mL at 72 hr produced highest cytotoxicity effects on Kasumi-1 cells. These results indicate that AgNPs can be biologically synthesised from V. cinerea and has potential to be used as an anticancer agents on acute myeloid leukaemia cell line
COMPARATIVE STUDY OF ANTIOXIDANT ACTIVITIES, COSMECEUTICAL PROPERTIES AND PHENOLIC ACIDS COMPOSITION OF FERMENTED RICE BRAN AND COCONUT TESTA
Authors: Abd Razak Dang Lelamurni , Jamaluddin Anisah , Abd. Rashid Nur Yuhasliza , Sharifudin Shaiful Adzni , Long Kamariah
Published: November 2016

Malaysia produces large number of agro-industrial products annually including rice and coconut. Along with the production, rice bran and coconut testa are also abundantly generated as by-products. Solid state fermentation (SSF) is a simple biotechnological technique that has been employed for production of bioactive compounds. The use of SSF on agro-industrial by-products is economically viable and helps to reduce the environmental impact of the by-products disposal. In this present study, rice bran (RB), coconut testa (CT) and a combination of rice bran and coconut testa (RBCT) were fermented with single culture of Aspergillus oryzae and Rhizopus oligosporus. The effect of fungal SSF on the cosmeceutical-related activities and phenolic acid content of the fermented RB, CT and RBCT extracts was determined. The results showed that total phenolic content (TPC) as well as antioxidant activity measured using the ferric reducing ability of plasma (FRAP) of all substrates increased upon fermentation. Contrary to the TPC and FRAP assays results, the radical-scavenging activity of the fermented samples as measured by using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, were varied. Tyrosinase inhibition activity was found to be the highest in the extract of RB fermented with A. oryzae (56.18%) compared to other extracts. The same extract showed the highest elastase inhibition activity with a value of 60.27%. High performance liquid chromatography (HPLC) analyses showed ferulic, sinapic, caffeic and protocatechuic acids were significantly increased in RB fermented with A. oryzae. The results of this study suggest that fungal solid-state fermentation of rice bran may have the potential to be exploited in producing different types of active metabolites that are useful for cosmeceutical industries
ANTIOXIDANT AND ANTIMICROBIAL PROPERTIES OF Tinospora crispa (putarwali) STEMS METHANOLIC EXTRACT
Authors: Sulaiman Fatimatul Akmal , Fuad Nurfarahin , Rahman Farawahida , Iqbal Anwar , Darnis Deny Susanti
Published: November 2016

Apart from being the primary source of food to other living things, plants also have medicinal value to treat various kinds of diseases. In recent years, it has been proposed that the extract from plants may be used as natural antioxidants which can help to prevent the generation of carcinogens in human body. In addition, plants also have antimicrobial agents to inhibit the growth of pathogenic microbes. This study was intended to investigate the antioxidant properties and antimicrobial activity of methanolic extract of Tinospora crispa stems extracted using soxhlet extraction method. The antimicrobial properties of T. crispa stems extract were tested using disc diffusion method against Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Candida albicans IMR C S23/11 A and Saccharomyces cerevisiae IMR S 617/068. The antioxidant properties of the extract were investigated by using Total Phenolics Content (TPC), Total Flavonoids Content (TFC), DPPH free radical scavenging and b–carotene bleaching assays.  The TPC value was 6.12 g GAE/100 g of dried extract while the TFC value was 55.58 g QE/100 g of dried extract. The IC50 of DPPH scavenging assay for the extract and ascorbic acid were 0.21 and 0.04 mg/mL, respectively. The average percentage of b–carotene bleaching assay was 38.3 % as compared to BHT, which was 45.1%.  The disc diffusion method showed no inhibition zone against all the strains of microorganisms at all concentrations of the extracts (0.5, 1.0, 2.5 and 5.0 mg/disc).
MARINE Streptomyces SP. UKMCC_PT15 PRODUCING UNDECYLPRODIGIOSIN WITH ALGICIDAL ACTIVITY
Authors: Zainal Abidin Zaima Azira , Ahmad Asmat , Latip Jalifah , Usup Gires
Published: November 2016

Marine actinomycetes are now in demand as they are capable of producing unique and novel compounds with wide biological activities. Marine Streptomyces sp. UKMCC_PT15  previously isolated from seawater collected in Pulau Tinggi, Johor was used in this study. Molecular identification showed high similarity of Streptomyces sp. UKMCC_PT15 with Streptomyces fradiae and S. diastaticus subsp. ardesiacus based on partial sequence of 16S rRNA gene. Further characterisations of this bacterium include spore morphology using SEM, growth on various media, salt tolerance test and carbon utilisation profile. This bacterium had straight spore chain with smooth-surfaced spores and was able to tolerate up to 11% NaCl with capabilities of utilising >40 carbon sources.  Undecylprodigiosin (C25H35N3O) was successfully purified through succession of column chromatography and finally using HPLC. Structure elucidation was confirmed through NMR spectroscopy, MS and comparison with established data. This compound demonstrated strong antibacterial activities against S. aureus, B. subtilis and C. albicans but weak antibacterial activities against E. coli, P. aeruginosa and Methicillin-resistant S. aureus (MRSA), Interestingly, undecylprodigiosin also demonstrated algicidal activity when tested against toxic dinoflagellates, A. minutum and P. bahamense, both of which are responsible for harmful algal blooms (HABs). Undecylprodiogiosin with concentration of 10-100 μg/ml gave ~100% algicidal activity against both dinoflagellates. Further testing with undecylprodigiosin concentration < 10 µg/ml showed that undecylprodigision was capable of killing significantly high numbers of both dinoflagellates, giving a high algicidal activity. Findings from this study suggested the potential use of undecylprodigiosin as algicidal agent which could be used for the mitigation of HABs
CRUDE OIL BIOREMEDIATION BY INDIGENOUS BACTERIA ISOLATED FROM OILY SLUDGE
Authors: Azizan Nur Hafizah , Ak Apun Kasing , Bilung Lesley Maurice , Vincent Micky , Roslan Hairul Azman , Awang Ahmad Husaini Awang Ahmad Sallehin
Published: November 2016

Enrichment culture technique leads to the discovery of six presumptive TPH-degrading bacteria. Identification and characterization tests using morphological, biochemical and molecular techniques have successfully isolated Pseudomonas aeruginosa (UMAS1PF), Serratia marcescens (UMAS2SF) and Klebsiella spp. (UMAS3KF). All strains were able to use crude oil as sole carbon and energy source for their growth since they were able to survive in Minimal Salt medium supplemented with 1% (v/v) crude oil. Growth study showed that they produced the highest cell counts on the third or fourth day by 108 – 1011 CFU/ml. Six artificial consortium inoculums have been produced from the growth study. Gas chromatography analysis showed that all isolates had the ability to degrade aliphatic hydrocarbon with 100% degradation of nC19 – C24. Among the isolates, UMAS2SF was the best and fastest n-alkane degrader with degradation percentage between 55 – 90% of n-C14 – C18 in 14 days. This was followed by UMAS1PF and UMAS3KF with 11 – 82% and 1.3% degradation, respectively. Enhancement study showed that plot with inoculum and NPK addition successfully enhanced n-alkane degradation. Plot A2:B3+NPK degraded n-alkane the fastest followed by plot treated by C+NPK, A1:B2, B+NPK and A2:B3. Result showed that UMAS1PF was the best PAHs degrader as most of the high molecular weight PAHs was degraded. In the enhancement study, the plot amended with A2:B3 showed the highest PAHs degradation, followed by plots A1:B2, A3:B1:C2 and A1:C3 that was assigned as the third, fourth and fifth best in mineralizing PAHs, respectively.
Combined Kinetic and Potential Energy Recovery Solution Applied to a Reach Stacker
Authors: Schaep Thomas , Marquis-Favre Wilfrid , Bideaux Eric , Noppe Eric , Rodot Pierre , Bernigaud Jean-Christophe , Langlois Vincent
Published: November 2016

Reach stackers are heavy duty mobile machines mainly used for container handling on intermodal terminals or harbors. The increasingly restrictive legislation on pollutant emissions as well as the need to reduce fuel costs for operators motivate manufacturers to design more efficient machines. Previous studies highlighted three ways to improve the fuel consumption, namely: (i) improving the engine efficiency; (ii) recuperating the potential energy of elevated containers; (iii) recovering the kinetic energy of the vehicle during decelerations. The architecture proposed in this paper combines these three requirements while preserving most of the conventional components. It results in a moderately priced solution. Control strategies are also studied, especially focusing on the potential energy recovery system where an input-output linearization method is compared to a conventional linear controller. Simulation conducted on several duty cycles shows fuel savings of up to 18.4% and a good robustness to cycle variations.
“Transparent Pump”: An Approach to Visualize Lifetime Limiting Factors in Axial Piston Pumps
Authors: Ivantysyn Roman , Weber Jürgen
Published: November 2016

The lifetime of axial piston pumps is depending on the application and it’s overall robustness to external loads, but even in ideal conditions pumps will fail eventually. The analytics to this problem are known to pump manufacturers. Bearing and shaft calculations paired with FEM models are invaluable tools, however the main questions remain with the rotating kit — cylinder block, piston, and slippers. If properly designed these parts should theoretically outlast the finite lifetime parts, such as roller bearings due to their hydrostatic and hydrodynamic bearings. In reality however failures still occur due to fatigue or other factors such as contamination or wear.

This paper describes the approach to measure and quantify the physical effects that occur in the lubricating gaps of axial pumps by means of simulation and measurements. Simulations are done with cooperation of Purdue University and the Caspar FSTI tool. These simulations are used to locate potential lifetime affecting areas and analyze them. The analysis includes temperature and pressure distributions in the gap with changing operating conditions and studies of the influence of wear and deformation on the parts that are forming the lubricating gaps. After the most critical areas are located within the simulation environment, gap and temperature sensors are placed right at these critical locations. This is planned at two of the three main lubricating gaps — slipper and swash plate as well as cylinder block and valve plate. In addition pressure sensors are placed within many critical areas of the pump, such as the transitional zone between high pressure and low pressure on the valve plate, as well as in the displacement chamber. The first results for the slipper/swashplate investigation of this approach will be shown in this paper.
A Numerical Study of High Pressure Flow Through a Hydraulic Pressure Relief Valve Considering Pressure and Temperature Dependent Viscosity, Bulk Modulus and Density
Authors: Osterland Sven , Weber Jürgen
Published: November 2016

This paper investigates the flow through a hydraulic pressure relief valve at high levels of operating pressure up to 700 bar (10000 Psi).

Following the flow path from the cold high pressure region before the metering edge to the warm low pressure region behind, the mean viscosity decreases by a factor of 16, the mean bulk modulus decreases by a factor of 2 and the mean density decreases by 6 %. Based on this preliminary considerations, a turbulent single phase flow considering pressure and temperature dependent viscosity, bulk modulus and density is modelled and steady state as well as transient calculations are performed.

The results of this study show that a pressure and temperature dependent viscosity reduces the pressure drop and the spool force by 10 % compared to a simulation with constant fluid parameters. Moreover, it is shown that compressible flow modelling has negligible influence on pressure drop and spool force — nevertheless, it is required to describe the temperature correctly. Due to the effect of volumetric work an incompressible model approach predicts the mean temperature rise 20 % too high. Finally, it was found that the temperature on the spool exceeds 400 °C. Afterwards, this fact is experimentally validated obtaining tempering colors in high pressure tests.
Motion Control Concepts for the Hydraulic Infinite Linear Actuator
Authors: Hochwallner Martin , Krus Petter
Published: November 2016

This contribution presents the novel Hydraulic Infinite Linear Actuator (HILA). It focuses on the control of motion and is based on simulation and analysis.

The novel actuator consists of two symmetric double acting cylinders with a common piston rod and hydraulically detachable pistons. Alternatingly one cylinder engages and drives the load while the other retracts, the HILA thus works in a kind of rope climbing motion.

The purpose of this contribution is to study the motion control of the HILA and to mimic the behaviour of a conventional cylinder. The HILA has three degrees of freedom which are temporarily coupled compared with one in a conventional cylinder. Further, the HILA with the chosen hydraulic system has two continuous and two digital control inputs. The challenge to be tackled is to combine the short stroke back and forth motions of the cylinders into a continuous smooth motion ofthe whole actuator.

Results from simulations and analyses show that the investigated concepts can keep the jerk within acceptable limits for many applications.
Investigation of Instability of a Pressure Compensated Vane Pump
Authors: Jenkins Ryan P. , Ivantysynova Monika
Published: November 2016

Currently, fixed displacement pumps are typically used to provide the oil flow required for actuation of the clutches, cooling, and lubrication of automatic transmissions. This results in significant power losses as excess flow at higher engine speeds is throttled through orifices back to the tank. Therefore, the use of variable displacement pumps to supply the required oil flow can reduce the overall fuel consumption of the vehicle by eliminating this excess flow at high engine speeds. This paper presents the development and experimental validation setup of a model for a pressure compensated pivoting-cam-type variable displacement vane pump (VDVP) that is suitable for these applications. The pump operates at low system pressures (typically ∼5 bar with maximum 20 bar) with significant amounts of entrained air present in the working fluid (typically 3% by volume at the delivery) over a wide range of input speeds (700–6000 rpm). These conditions, along with a combination of a highly dynamic flow demand and dynamically changing pressure compensation setting, result in pump instabilities and loss of controllability. Previously, high leakage flow rates were introduced into the cam displacement control volume in an attempt to stabilize the pump with limited improvements. A high fidelity simulation model of the VDVP displacement chambers and cam displacement control volume pressure development was created in MATLAB/Simulink to accurately predict pump flow rates and cam dynamics in order to investigate these instabilities and methods for increasing the controllability of the VDVP. Additionally, the model provides a platform to assess the system sensitivity to changes in fluid/air mixture ratio, vane spacing, bias spring rate, and pump outlet pressure. A modified pump that was instrumented to measure the pressure gradients within each displacement chamber at the transitions between the suction and delivery ports under realistic operating conditions is presented. The modified pump was also instrumented with a linear variable displacement transducer (LVDT) to directly measure cam position during pump operation on an experimental test bed incorporating actual control valves found in an automatic transmission.
Influence of the Lubricant Thermo-Piezo-Viscous Property on Hydrostatic Bearings in Oil Hydraulics
Authors: Johansen Per , Roemer Daniel B. , Andersen Torben O. , Pedersen Henrik C.
Published: November 2016

In fluid power machinery hydrostatic bearings are frequently used, and a first approximation approach to design is determination of a balance ratio by analytical calculation of the hydrostatic pressure force. Usually this is performed assuming that the thermo-piezo-viscous property can be neglected. However, in applications as piston machines, where pressure in many cases exceeds 200 Bar, such assumption leads to considerable error in the balance ratio prediction, due to the piezo-viscous property of the lubricant. Furthermore, the thermo-viscosity relation also has a significant influence, which adds to the discrepancy of such simple design approach. In this paper the hydrostatic pressure force calculation is reviewed in terms of thermohydrodynamic (THD) lubrication theory, and simple analytical approximations of the hydrostatic pressure force, incorporating the piezo-viscous and thermo-viscous property of the lubricant, are presented. In order to investigate validity of the approximations a numerical THD model is developed. A comparison study of the numerical and analytical predictions is performed in order to validate the simple design approach. In addition, the assumptions that form the basis of these analytical approximations are explored in order to clarify the limits of application. In conclusion, it is found that the spatial gradient of the thermal field on the bearing surface is the significant factor in the thermo-viscous effect on the hydrostatic pressure profile, which leads to the conclusion that design engineers need to understand the thermodynamics of hydrostatic bearings, when using the conventional simple analytical approach, neglecting thermo-piezo-viscosity, in hydrostatic pressure force calculations.
Analysis of the Thermo-Viscous Effect on Friction and Energy Dissipation in Oil Lubricated Interfaces
Authors: Johansen Per , Roemer Daniel B. , Andersen Torben O. , Pedersen Henrik C.
Published: November 2016

The last decade an increasing amount of work are performed with the aim of enhancing efficiency and reliability of fluid power components. Consequently, the loss mechanisms of lubricated tribological interfaces are of particular interest. This has led to development of sophisticated three-dimensional thermo-elasto-hydrodynamic lubrication models of fluid power components. The computational efforts involved in simulation with such models entail that design optimization are to some extend impractical. However, such models are also pursued in theoretical tribology with the aim to study loss and wear mechanisms, which is very difficult to study experimentally. In consequence, advanced numerical models are the state of the art approach in theoretical fluid power tribology research. However, a downside of modern numerical models is the inability to provide a practical tool for wide-scale parameter sweep investigations, due to computational effort, whereby analytical research in loss mechanisms still have certain advantages. In this paper, the thermo-viscous effect of a lubricant is included in an analytical study of the friction and energy dissipation of oil hydraulic thin-films. This analytical study is based on an asymptotic approximation of the laminar lubrication thermal field at low reduced Peclet and Brinkman number, where viscosity is included as a function of temperature. The asymptotic series is truncated at first order and used to derive an expression of the viscous friction on a sliding surface. This reveal an influence from the surface temperature gradient on the viscous friction, which is not revealed when applying classical isothermal analysis. The significance of the thermo-viscous effect on friction and energy dissipation is analyzed analytically in order to provide a qualitative insight to the relation between thermodynamic properties, film thickness, sliding velocity and viscous friction.
A Three-Dimensional CFD Methodology to Study Vane-Ring and Vane-Under-Vane Interactions of a Vane Pump Power Split Transmission
Authors: Frosina Emma , Senatore Adolfo , Buono Dario , Stelson Kim A. , Wang Feng , Gao Haiyang
Published: November 2016

This paper presents a study of a novel vane pump power split transmission (VPPST). The transmission incorporates a new component, the Vane Power Split Unit (VPSU). The VPSU is a double-acting vane pump with a floating ring where the input shaft is connected to the engine and the floating ring is connected to the output shaft. The VPSU generates hydraulic oil flow at a rate proportional to the difference in angular velocities between the input and output shafts. This flow enters a hydraulic motor mounted to the output shaft. The vane pump power split transmission (VPPST) is a combination of the double-acting vane pump (VPSU) and the hydraulic motor directly connected to the pump.

A CFD model of the VPSU has been created to better understand its performance. The model uses the three-dimensional CFD commercial code PumpLinx®, developed by Simerics® Inc.

Thanks to collaboration with the code developers, the model is able to predict the complex fluid dynamics in the pockets in the rotor into which the vanes retract. These pockets are referred to as under-vane volumes. The rotor of the vane pump, in fact, has several internal channels that connect the pumping chambers between the vanes to the under-vane volumes. The combination of the vanes and the internal ducts and volumes of the under-vanes have been modelled as dynamic “valves” that rotate with the rotor. In this way the radial movements of the vanes are computed as a part of the simulation, based on the pressures due to the compression of the volumes on the inner diameter side of the vanes.

The study is a result of collaboration between the University of Minnesota and the University of Naples “Federico II” research groups and the code developers of Simerics® Inc. The universities and Simerics® Inc. have all been involved in this project, working in close cooperation for the model building and simulations.
Lyapunov Based Adaptive Control Method for Hydraulic Servo Drive
Authors: Roozbahani Hamid , Frumkin Konstantin , Handroos Heikki
Published: November 2016

Adaptive control systems are one of the most significant research directions of modern control theory. It is well known that every mechanical appliance’s behavior noticeably depends on environmental changes, functioning-mode parameter changes and changes in technical characteristics of internal functional devices. An adaptive controller involved in control process allows reducing an influence of such changes. In spite of this such type of control methods is applied seldom due to specifics of a controller designing.

The work presented in this paper shows the design process of the adaptive controller built by Lyapunov’s function method for a hydraulic servo system. The modeling of the hydraulic servo system were conducting with MATLAB® software including Simulink® and Symbolic Math Toolbox™. In this study, the Jacobi matrix linearization of the object’s mathematical model and derivation of the suitable reference models based on Newton’s characteristic polynomial were applied. In addition, an intelligent adaptive control algorithm and system model including its nonlinearities was developed to solve Lyapunov’s equation.

Developed algorithm works properly and considered plant is met requirement of functioning with. The results shows that the developed adaptive control algorithm increases system performance in use devices significantly and might be used for correction of system’s behavior and dynamics.