bluuebunny/crossref_metadata_2025 huggingface dataset:
Dependence of brittle-to-ductile transition on crystallographic direction in diamond turning of single-crystal silicon
Authors: Jasinevicius R G , Duduch J G , Montanari L , Pizani P S
Published: October 2011

The objective of this paper is to show the dependence relationship between the crystallographic orientations upon brittle-to-ductile transition during diamond turning of monocrystalline silicon. Cutting tests were performed using a −5° rake angle round nose diamond tool at different machining scales. At the micrometre level, the feedrate was kept constant at 2.5micrometres per revolution (µm/r), and the depth of cut was varied from 1 to 5 µm. At the submicrometre level, the depth of cut was kept constant at 500 nm and the feedrate varied from 5 to 10 µm/r. At the micrometre level, the uncut shoulder generated with an interrupted cutting test procedure provided a quantitative measurement of the ductile-to-brittle transition. Results show that the critical chip thickness in silicon for ductile material removal reaches a maximum of 285 nm in the [100] direction and a minimum of 115 nm in the [110] direction, when the depth of cut was 5 µm. It was found that when a submicrometre depth of cut was applied, microcracks were revealed in the [110] direction, which is the softer direction in silicon. Micro Raman spectroscopy was used to estimate surface residual stress after machining. Compressive residual stress in the range 142 MPa and smooth damage free surface finish was probed in the [100] direction for a depth of cut of 5 µm, whereas residual stresses in the range 350 MPa and brittle damage was probed in the [110] direction for a depth of cut of 500 nm.
A method to predict the non-linear vibratory response of bladed disc system with shrouded dampers
Authors: Gu W , Xu Z , Liu Y
Published: October 2011

The prediction accuracy of the non-linear vibratory response of bladed disc system with shrouded dampers depends on the modelling of bladed disc system, the friction contact model for depicting the non-linear constraint force, and the solution method of non-linear vibration equations of the bladed disc system. In order to improve the computation efficiency, the bladed disc system is assumed to be tuned in this article. Under this assumption, the vibratory response of the bladed disc system can be predicted based on a sector model having the cyclically symmetric constraint. This article particularly describes the formulation of the sector model and the infliction of cyclically symmetric constraint. The proposed three-dimensional (3D) friction contact model used to depict the non-linear constrained force is a numerical method, in which the relative motion of the contact surfaces is an arbitrary complex periodical one. The hybrid frequency–time domain (HFT) method is applied to solve the non-linear vibration equations of the bladed disc system for its high computation efficiency and computation accuracy. Finally, based on the sector model, numerical 3D friction contact model, and HFT domain method, a method is developed to predict the non-linear vibratory response of the bladed disc system with shrouded dampers.
Effect of heat treatment on the magnetic behaviour of powder steel 50Ni2Mo under uni-axial tension
Authors: Gorkunov E S , Subachev Y V , Zadvorkin S M , Ulyanov A I , Goruleva L S
Published: October 2011

In this study, investigation results on the effect of heat treatment conditions on the mechanical properties, internal stresses, magnetic characteristics, and electrical resistivity of powder steel 50Ni2Mo are presented. Coercive force and maximum magnetization are shown to be applicable as magnetic test parameters to reveal underheating for quenching. Heating for quenching above the critical point [Formula: see text] up to 910°С has an insignificant effect on the mechanical characteristics of the steel tested. It has been demonstrated that the use of the coercive force measured on minor magnetic hysteresis loops is preferable when estimating the level of applied tensile stresses in heat-treated powder steel 50Ni2Mo.
Mathematical modelling of the pneumatic relay emergency valve for dual-line agricultural trailer braking systems
Authors: Kamiński Z
Published: October 2011

A mathematical model of the trailer relay emergency valve used in the pneumatic braking systems of agricultural trailers has been presented. The differential equations of the model allow for the inertia of control elements, static and kinetic friction, and heat exchange in individual valve chambers. The developed mathematical valve model was used for simulation of the transient processes in the dual-line braking system of a single-axle agricultural trailer. The computer models for individual components of the braking system were made within the program MATLAB/Simulink in the form of S-function-type functional structural blocks based on original algorithms. The positive results of validation of the trailer braking system computer model show a potential for a wider use of dynamic computations in the computer-aided process of designing pneumatic vehicle braking systems.
Sufficiently premixed compression ignition of a gasoline-like fuel using three different nozzles in a diesel engine
Authors: Won H-W , Peters N , Tait N , Kalghatgi G
Published: October 2011

Fuels that are more resistant to autoignition allow more time for mixing before combustion occurs and help to reduce nitrogen oxides (NO x) and smoke in a diesel engine. However, hydrocarbon (HC) and carbon monoxide (CO) emissions are high at low loads because combustion is more likely to take place in lean mixture packets with better mixing caused by longer ignition delays. These problems can be significantly alleviated by managing the mixture strength by changing the injection pressure and the nozzle geometries. A single-cylinder diesel engine is run on a mixture of gasoline and diesel with a research octane number of 91, at different speeds, loads, and exhaust gas recirculation levels using three different nozzles. It is much easier to obtain low NO x and low smoke emissions with this fuel than with a European diesel fuel using the standard nozzle. Larger injector holes and lower injection pressures help to reduce the HC and CO emissions at low loads and also enable the gasoline-like fuel to run at a higher speed of 4000 r/min at a reasonably high load (indicated mean effective pressure) of 10 bar.
Diatom evidence of climatic change in Holsteinsborg Dyb, west of Greenland, during the last 1200 years
Authors: Sha Longbin , Jiang Hui , Knudsen Karen Luise
Published: October 2011

Diatom assemblages from Holsteinsborg Dyb on the West Greenland shelf were analysed with high temporal resolution for the last 1200 years. A high degree of consistency between changes in frequency of selected diatom species and instrumental data from the same area during the last 70 years confirms the reliability of diatoms (particularly sea-ice species and warm-water species) for the study of palaeoceanographic changes in this area. A general cooling trend with some fluctuations is marked by an increase in sea-ice species throughout the last 1200 years. A relatively warm period with increased influence of Atlantic water masses of the Irminger Current (IC) is found at ad 750–1330, although with some oceanographic variability after ad 1000. A pronounced oceanographic shift occurred at ad 1330, corresponding in time to the transition from the so-called ‘Medieval Warm Period’ (MWP) to the ‘Little Ice Age’ (LIA). The LIA cold episode is characterized by three intervals with particularly cold sea-surface conditions at ad 1330–1350, ad 1400–1575 and ad 1660–1710 as a result of variable influence of Polar waters in the area. During the last 70 years, two relatively warm periods and one cold period (the early 1960s to mid-1990s) are indicated by changes in the diatom components. Our study demonstrates that sedimentary records on the West Greenland shelf provide valuable palaeoenvironment data that confirm a linkage between local and large-scale North Atlantic oceanographic and atmospheric oscillations.
A case of pure red cell aplasia and immune thrombocytopenia complicating systemic lupus erythematosus: Responseto rituximab and cyclophosphamide
Authors: Gupta RK , Ezeonyeji AN , Thomas AS , Scully MA , Ehrenstein MR , Isenberg DA
Published: October 2011

Pure red cell aplasia (PRCA) is a recognized but rare complication of systemic lupus erythematosus (SLE) and is characterized by the near absence of red blood cell precursors in the bone marrow but with normal megakaryocyte and granulocytes. We report a novel case of acquired PRCA occurring simultaneously with immune thrombocytopenia in the context of active SLE. Both syndromes were refractory to conventional treatment but responded to rituximab and cyclophosphamide.
Impaired control of the tissue factor pathway of blood coagulation in systemic lupus erythematosus
Authors: Adams MJ , Palatinus AA , Harvey AM , Khalafallah AA
Published: October 2011

Thrombosis is a frequent manifestation in patients with systemic lupus erythematosus (SLE), although precise mechanisms remain unclear. This study investigated whether the major physiological trigger of blood coagulation, the tissue factor (TF) pathway, was altered in SLE patients. Furthermore, we investigated potential associations between the TF pathway, the presence of antiphospholipid (APL) antibodies and other abnormalities present in SLE. A total of 101 participants (40 SLE patients and 61 age- and sex-matched controls) were recruited from Tasmania, Australia. Markers of the TF pathway, hypercoagulability, inflammation and endothelial cell damage were measured in plasma. Serum levels of APL antibodies (anti-cardiolipin antibodies [ACL], lupus anticoagulants [LAC], anti-beta2-glycoprotein-1 [anti-β2GP1] and anti-prothrombin antibodies) were also determined. Despite similar TF and TF pathway inhibitor (TFPI) total antigen levels, SLE patients had significantly increased levels of TFPI free antigen (patients vs controls; mean ± SD) (11.6 ± 0.9 ng/mL vs 6.4 ± 0.4 ng/mL; p < 0.001) but significantly reduced TFPI activity (0.66 ± 0.07 U/mL vs 1.22 ± 0.03 U/mL; p < 0.001), compared with healthy controls. Anti-TFPI activity, designated as the ability of isolated IgG fractions to inhibit TFPI activity in normal plasma, was detected in 19/40 (47.5%) of SLE patients and 3/40 (7.5%) of healthy controls. The significant reduction in TFPI activity in SLE patients reflects impaired functional control of the TF pathway. Moreover, SLE patients with a history of thrombosis demonstrated higher levels of TFPI activity compared with patients without a previous thrombotic event (0.97 ± 0.07 U/mL vs 0.53 ± 0.14 U/mL; p = 0.0026). Changes to the TF pathway were not associated with manifestations of SLE such as inflammation or endothelial cell damage. The results from this study suggest hypercoagulability in SLE may (in part) be due to reduced TFPI activity, a mechanism that appears to be independent of other abnormalities in SLE.
Vitamin D deficiency as marker for disease activity and damage in systemic lupus erythematosus: a comparison with anti-dsDNA and anti-C1q
Authors: Mok CC , Birmingham DJ , Ho LY , Hebert LA , Song H , Rovin BH
Published: October 2011

Objectives: To study the sensitivity and specificity of vitamin D deficiency for predicting disease activity and damage of systemic lupus erythematosus (SLE) in comparison with anti-dsDNA and anti-C1q. Methods: Consecutive patients who fulfilled four or more ACR criteria for SLE were studied. Levels of 25-hydroxyvitamin D3, anti-C1q, anti-dsDNA and complement levels were measured. Relationship among these markers, concurrent disease activity and damage scores of SLE was studied by Spearman's rank correlation method. Results: In total, 290 SLE patients were studied (95% women; mean age 38.9 ± 13.1 years; SLE duration 7.7 ± 6.7 years). Clinical or serological lupus activity (SLEDAI ≥ 1) was present in 225 (78%) patients. Vitamin D deficiency (< 15 ng/ml) was detected in 78 (27%) patients. Levels of 25-hydroxyvitamin D3 correlated inversely with the clinical SLE disease activity score (Rho = −0.26; p < 0.001). A negative correlation was also observed between 25-hydroxyvitamin D3 and anti-dsDNA levels (Rho = −0.13; p = 0.02), or anti-C1q (Rho = −0.14; p = 0.02). However, there was no significant relationship between levels of 25-hydroxyvitamin D3 and complement C3 (Rho = 0.09; p = 0.12) or C4 (Rho = 0.09; p = 0.13). Both 25-hydroxyvitamin D3 deficiency and anti-C1q were more specific but less sensitive than anti-dsDNA for concurrent clinical renal and non-renal SLE activity. Levels of 25-hydroxyvitamin D3, anti-dsDNA or anti-C1q did not correlate significantly with the SLE damage scores. Conclusions: 25-hydroxyvitamin D3 correlated inversely and significantly with clinical SLE activity, anti-C1q and anti-dsDNA titers, but not with complement levels or damage scores. Deficiency of 25-hydroxyvitamin D3 was as specific as anti-C1q, but less sensitive than anti-dsDNA, for detecting concurrent renal and non-renal clinical activity of SLE.
Influence of antiphospholipid antibody levels and type on thrombotic manifestations: results from the Serbian National Cohort Study
Authors: Stojanovich L , Markovic O , Marisavljevic D , Elezovic I , Ilijevski N , Stanisavljevic N
Published: October 2011

Repeated thromboses are the most frequent clinical manifestation of antiphospholipid syndrome (APS) in the presence of antiphospholipid antibodies (aPL). The objective of this study was to observe the prevalence and localization of thrombosis, and to investigate the importance of aPL type and level for thrombosis-related events in patients diagnosed with APS. These are the first results of patients enrolled in Serbian National Cohort Study which comprises 256 patients: 162 with primary antiphospholipid syndrome (PAPS) and 94 with APS associated with systemic lupus erythematosus (SLE). aPL analysis included detection of aCL (IgG/IgM), β2GPI, and lupus anticoagulant. Thrombosis was diagnosed in 119 (46.5%) patients, with higher prevalence in PAPS compared with SLE patients (51.2% and 38.3%, respectively, p = 0.045). There was similar prevalence of arterial thrombosis in PAPS and SLE groups (34.6% and 34%, respectively, p = 0.932) although venous thrombosis was more frequent in PAPS (25.9% and 8.5%, respectively, p = 0.001). Thrombosis was observed in 92 (55.8%) patients who had more than one type of antibody (category I), in 13 (41.9%) patients with category IIa, in 19 (46.3%) patients with category IIb, and in 73 (44.2%) patients with category IIc ( p = 0.10). The patients with thrombosis were older than those without thrombosis (49.8 and 39.8 years, respectively, p = 0.001). Overall, older age was a risk factor for thrombosis. The prevalence of venous thrombosis was higher in the PAPS group, but with lower frequency than in literature data. Any aPL type and level is a risk factor for thrombosis.
Rituximab induces resolution of recurrent diffuse alveolar hemorrhage in a patient with primary antiphospholipid antibody syndrome
Authors: Elazary A Scheiman , Klahr PP , Hershko AY , Dranitzki Z , Rubinow A , Naparstek Y
Published: October 2011

Diffuse alveolar hemorrhage (DAH) is a rare manifestation of primary antiphospholipid antibody syndrome (APS). We describe a patient with primary APS and refractory recurrent episodes of DAH. The patient was admitted 15 times due to recurrent episodes of DAH in a period of 18 months. Multiple immunosuppressive drugs did not improve his condition. Two years after his presentation, he was treated with rituximab (two doses of 1 g, 2 weeks apart). Six months later, the attacks of DAH have gradually disappeared. In a follow-up of more than 2 years after he received rituximab, the patient has had no further admissions due to DAH. Levels of antiphospholipid antibodies were measured during follow-up of 4 years. Anti-β2 glycoprotein IgG titer decreased to normal 6 months after therapy but anticardiolipin (aCL) antibody titer increased. We conclude that rituximab caused a dramatic clinical response in this patient. Anti-β2 glycoprotein IgG correlated better with the clinical response in this patient than aCL.
Therapeutic Recreation in Education
Authors: Hawkins Brent L. , Cory Lynne A. , McGuire Francis A. , Allen Lawrence R.
Published: October 2011

Although therapeutic recreation (TR) services are provided in many different health and human service sectors, TR struggles with gaining acceptance by other human service fields, demonstrating efficacy of services, and inclusion in various disability policies, specifically within special education. There are many explanations for the underrepresentation such as poor advocacy for TR services, lack of specification in educational policy, and unresolved philosophical differences in the profession. This article provides an overview of the TR profession, the policies that enable the use of TR services, and how TR services can contribute to the educational outcomes of students with disabilities. Recommendations for improving the representation of TR services within special education services are also discussed.
Irreversible Effects in Magnetorheological Fluids
Authors: Gorodkin S. , James R. , Kordonski W.
Published: October 2011

The effect of residual structure on properties of MR fluids, based on CI particles, was investigated using a magneto-sweep technique and initial magnetic susceptibility measurements. The shear rate, particle size, and the CI surface properties were among the experimental variables. A mechanical hysteresis, associated with the irreversible residual structure formation, was observed via measurements of both shear stress and first normal stress difference. The hysteresis was most pronounced at the creeping flow as compared to high shear conditions. Regardless of experimental settings, the level of the hysteresis was the same at high shear rate, while the fluids containing larger particles and higher CI concentrations demonstrated stronger residual effect at slow flow. The hysteresis loop was slightly wider for the silica-treated particles suggesting that chemical (non-magnetic) interaction might contribute to the fluid irreversible behavior. Existence of some residual structure has been also shown in measurements of initial magnetic susceptibility of MR fluids. After exposure to a sequence of DC magnetic fields, fluids exhibited higher susceptibility presumably caused by the formation of residual structures of larger size than those in the initial state.
Comparison of 1.5 and 3.0 T for Contrast-Enhanced Pulmonary Magnetic Resonance Angiography
Authors: Londy Frank Joseph , Lowe Suzan , Stein Paul D. , Weg John G. , Eisner Robert L. , Leeper Kenneth V. , Woodard Pamela K. , Sostman H. Dirk , Jablonski Kathleen A. , Fowler Sarah E. , Hales Charles A. , Hull Russell D. , Gottschalk Alexander , Naidich David P. , Chenevert Thomas L.
Published: October 2011

Objective: In a recent multi-center trial of gadolinium contrast-enhanced magnetic resonance angiography (Gd-MRA) for diagnosis of acute pulmonary embolism (PE), two centers utilized a common MRI platform though at different field strengths (1.5T and 3T) and realized a signal-to-noise gain with the 3T platform. This retrospective analysis investigates this gain in signal-to-noise of pulmonary vascular targets. Methods: Thirty consecutive pulmonary MRA examinations acquired on a 1.5T system at one institution were compared to 30 consecutive pulmonary MRA examinations acquired on a 3T system at a different institution. Both systems were from the same MRI manufacturer and both used the same Gd-MRA pulse sequence, although there were some protocol adjustments made due to field strength differences. Region-of-interests were manually defined on the main pulmonary artery, 4 pulmonary veins, thoracic aorta, and background lung for objective measurement of signal-to-noise, contrast-to-noise, and bolus timing bias between centers. Results: The 3T pulmonary MRA protocol achieved higher spatial resolution yet maintained significantly higher signal-to-noise ratio (≥13%, p = 0.03) in the main pulmonary vessels relative to 1.5T. There was no evidence of operator bias in bolus timing or patient hemodynamic differences between groups. Conclusion: Relative to 1.5T, higher spatial resolution Gd-MRA can be achieved at 3T with a sustained or greater signal-to-noise ratio of enhanced vasculature.
Prevention and Treatment of Doxorubicin-Induced Cardiotoxicity by Dexrazoxane and Schisandrin B in Rabbits
Authors: Che Feifei , Liu Yu , Xu Caigang
Published: October 2011

The cost of dexrazoxane, a drug used to provide protection from doxorubicin-induced cardiotoxicity, limits its use in low-income countries. We aimed to see whether schisandrin B, an inexpensive drug, could provide protection equivalent to that provided by dexrazoxane. New Zealand white rabbits were randomly divided into groups and treated with saline, doxorubicin, doxorubicin + dexrazoxane, or doxorubicin + schisandrin B. Doxorubicin-induced damage and the protective effects were studied by recording the echocardiographic parameters and serum levels of superoxide dismutase, malondialdehyde, cardiac troponin I, and brain natriuretic peptide and observing the histology and degree of apoptosis. Schisandrin B had dose-dependent effects in decreasing the magnitude of doxorubicin-induced indicators of cardiomyopathy to a degree that approximated the decrease produced by dexrazoxane treatment. Schisandrin B might be a useful, low-cost alternative drug for this application.
Genotoxicity Evaluation of Dimethoate to Experimental Mice by Micronucleus, Chromosome Aberration Tests, and Comet Assay
Authors: Ayed-Boussema Imen , Rjiba Karima , Mnasri Nourhène , Moussa Amal , Bacha Hassen
Published: October 2011

Dimethoate (DM) is an organophosphate insecticide with numerous uses on field and agricultural crops and ornamentals. Data concerning DM-acute genotoxicity are controversial and knowledge on its delayed effect is limited. For this reason, we aimed to further explore DM genotoxicity resulting from subchronic intoxication of experimental mice. Thus, DM was administered to mice at doses ranging from 1 to 30 mg/kg body weight for a period of 30 consecutive days. There was a significant increase ( P < .05) in the frequency of micronucleated bone marrow cells following DM administration. Furthermore, the chromosome aberration assay revealed a significant increase in the percentage of chromosome abnormalities in a dose-dependent manner. Dimethoate was also found to induce significant DNA damage in mouse bone marrow cells as assessed by the comet assay. Altogether, our results showed that, after a subchronic exposure, DM was a genotoxic compound in experimental mice.
Fantasies of power: Performing Europeanization on the European periphery
Authors: Jones Shannon , Subotic Jelena
Published: October 2011

This article offers a fresh look at contemporary processes of Europeanization. Using the Eurovision Song Contest as empirical illustration of how states perform Europeanization, this article makes three principal arguments. First, it challenges optimistic accounts of cultural Europeanization and identifies the limits that the Europeanization project faces. Second, it proposes that the process of Europeanization is fundamentally a process of political imagination. How states choose to Europeanize, which attributes of Europe they accept and which ones they reject are shaped by what they imagine Europe to be and what they imagine their role in Europe is. Third, it argues that European states with uncertain or transitional identities on the European ‘periphery’ use performative symbols, such as carnivals, festivals or cultural events to express their fantasies about power and equality within the international system.
The French connection
Authors: Jordan Matthew F.
Published: October 2011

In the 20th century, jazz music spread throughout global culture like few other musical forms. Over the 40-year period in which jazz was assimilated into French culture, myths about the origin of jazz played an important role in the discourse surrounding the music. By examining both how these myths functioned in the discourse and examining how they changed over time depending on cultural circumstances, this article shows how writers increasingly used jazz etiologies and writing on the importance of New Orleans to the history of jazz to bridge the cultural gap and to make a French connection with jazz music, so that the enjoyment of it could be experienced as authentically French. From early abstract expressivist origins, to the latter strategic deployment of these myths as a feature of New Orleans revivalism, this discourse played an important role in the integration of jazz into French cultural identity.
Coming to terms with sexualization
Authors: Duits Linda , van Zoonen Liesbet
Published: October 2011

Not since the feminist pornography debates of the 1980s has there been such an outburst of discussion, research and publications about sexualized images of women and girls. The debate is now carried out by governments and other social actors, but to hail current attacks on sexualization as a belated victory for feminism is naive and problematic, as discussed in this article. We contend that current sexualization policies involve academic analyses and political solutions which are cast in the discourse of liberal feminism and neoliberalism. Inevitable in the current work on sexualization is an identity of girls and young women as ‘victims’ in need of protection. Research among Dutch girls is utilized to refute that construction, emphasizing tactics of resistance, negotiation and accommodation which they have developed. Current sexualization concerns are ahistorical in their oblivion to similar sexualization panics in previous decades and to the years of feminist cultural analysis and critique in this arena.
Socio-symbolic homologies: Exploring Paul Willis’ theory of cultural forms
Authors: Trondman Mats , Lund Anna , Lund Stefan
Published: October 2011

Thirty years have passed since Paul Willis formulated a theory of cultural forms in the appendix to his seminal work Profane Culture. In this article we are driven by the conviction that Willis’ theory is a forgotten treasure trove that needs to be recovered, challenged and developed. The argument is guided by three aims. First, we provide a construction of the theory’s main content. Second, we search for possibilities of enlarging the content and scope of his theory. Third, we reconstruct one of the basic underlying arguments of Willis’ theory, that cultural items in themselves carry a given meaning in relation to social groups. In so doing we partly reconstruct Willis’ understanding of ‘objective’ possibilities as something essentially given in time and space. We utilize the example of the car make Cadillac to demonstrate that cultural items also attract because they are already occupied by socioculturally constructed systems of meaning.
Health Promoting Spatial Design Characteristics of Korean Apartment House in a User-Benefit Perspective
Authors: Lee Yeunsook , Jang Miseon , Ahn Changhoun
Published: October 2011

This study was intended to evaluate the empirically spatial design characteristics from a perspective of users and to determine what kind of benefits that health-promoting spatial design characteristics can give to residents. The major method used in this study was the web questionnaire survey. Two hundred ten people between the ages of thirty and fifty who live in Seoul and the metropolitan area were surveyed. As a result, “Physiological Maintenance” was ranked top in the list of four categories for user benefit criteria (UBC), followed by behavioural facilitation, social facilitation and perceptual maintenance. Among the items of sub-categories, consumer’s demand for physiological maintenance was most highly regarded as essential. Demand for “No poisonous element” was the highest followed by “Good natural and artificial ventilation” and “Good day-lighting.” In this study, health promoting, spatial design characteristics were investigated pragmatically based on the UBC theory as well as diverse demands given by the residents. This paper was presented to provide the design characteristics that are required for healthy housing to meet the various consumers’ demand. The findings of this study would provide pragmatic information for architectural design for healthy living.
Potential of using black palm kernel oil in austempering of ductile cast iron use in the production of agricultural implements
Authors: Idirs U D , Aigbodion V S , Shehu M A
Published: October 2011

The suitability of using black palm kernel oil as austempering medium for ductile iron to be used in austempering agricultural implements was investigated. The ductile iron was cut and machined into tensile, impact, and hardness test samples, austenitized at 950 °C, soaked for 2 h, and quenched in the black palm kernel oil bath maintained at a temperature of 270 °C. The samples were held in this bath for 1, 2, 3, 4, and 5 h, respectively. Then, the tensile strength, hardness values, and impact energy of both the austempered and as-cast samples were determined. It was observed that austempering significantly increases the tensile strength and impact energy of the ductile iron apart from achieving an appreciable increase in hardness. Also, the tensile strength, hardness, and impact values obtained for the austempered ductile iron using black palm kernel oil tally with recommended values of standard ductile iron austempered in standard salt bath implying that black palm kernel oil can be used as bath for the austempering of ductile iron. The oil was used in austempering tractor spindle (disc carrier) and the practical result was successful.
Exploring the interplay of adsorption and diffusion for separation of CO2/CH4 in zeolite-like metal–organic frameworks by a molecular dynamics simulation
Authors: He P , Liu H , Li Y , Huang S , Zhu J , Tian H
Published: October 2011

Atomically detailed simulations were performed to explore the coupled effects of adsorption and diffusion on the structural and transport properties of CO2, CH4, and their equimolar mixture in Na+ ion-exchanged rho zeolite-like metal–organic framework (Na- rho-ZMOF). It is observed that the adsorption of CO2 in rho-ZMOF leads to slight slowing-down and speeding-up of the drift motion of Na+ ions, depending on loading of CO2 molecules. The simulations of the diffusivities of single-component CO2 and CH4 indicate that a maximum diffusivity with varying loadings exists for both components, and for CO2 the maximum diffusivity arises mainly from the electrostatic interactions between the CO2 quadrupole moment and framework charges. According to our simulation results of the equimolar mixture, with an increase in loading, a diffusion selectivity reversal of CO2 over CH4 is observed; adsorption is the main factor for the separation process of CO2 and CH4 in Na- rho-ZMOF; and the permselectivity of CO2 with respect to CH4 as a function of total pressure also shows a maximum and finally approaches a plateau with an overall value of about 40.0, which is higher than many other commonly used MOF materials such as Cu-BTC and isoreticular MOFs at the same pressure.
Effect of geometrical and mechanical properties on behaviour of sandwich beams with functionally graded face sheets under indentation loading
Authors: Mohammadi Y , Khalili S M Reza
Published: October 2011

Improved high-order sandwich beam theory is used to model the local deformation ofsandwich beams with aluminium/alumina functionally graded (FG) face sheets loaded by central indentor. First-order shear deformation theory is used for the FG face sheets while three-dimensional elasticity is used for the flexible core. Using the model to consider the way in which different wavelengths of sinusoidal pressure loading on the upper FG face sheet are transmitted to the core and lower FG face sheet, two spreading length scales λt and λb are introduced and calculated; λt and λb, which are two functions of the beam material and geometrical properties, characterize the length over which a load on the upper surface of a beam is spread out by the face sheets and the core. Comparison of the semi-wavelength of the sinusoidal pressure loading ( L/m) on the upper FG face sheet with length scales λt and λb illustrate the importance of these length scales in describing whether the face sheets act in a rigid or a flexible manner. When the semi-wavelength ( L/m) of the applied load in the present example is higher than λt (or λb), 10–90 per cent (or 5–70 per cent) of the contact load is transmitted locally to the core (or from the core to the lower FG face sheet) for the geometries and materials analysed. Conversely, when L/m is lower than λt (or λ1b), the contact load from the upper FG face sheet with a maximum of 58 per cent (or 70 per cent) is spread out over a wider area of the core (or from the core is spread out over a wider area of the lower FG face sheet). Reasonable agreement is found between the theoretical predictions in this study and finite element method results by ANSYS and the results published in literature for special cases.
A note on a hierarchical interpretation for negative variance components
Authors: Molenberghs Geert , Verbeke Geert
Published: October 2011

A lot has been said about the relationship between hierarchical models, such as linear mixed-effects models, and the marginal models they imply. Generally, there is a many-to-one map of hierarchical models onto a given marginal model. Additionally, in some cases, no obvious hierarchical model leads to a given marginal model. For example, it is commonly known that the random-intercepts model produces, marginally, a compound-symmetry model with non-negative intraclass correlation, whereas, on the other hand, a compound-symmetry model with negative intraclass correlation is not induced by a conventional random-intercepts model. We show here that it is still possible, and even intuitively appealing, to formulate hierarchical models inducing structure such as negative compound-symmetry correlation. Thus, the aim of this note is to further clarify the relationship between hierarchical and marginal models, enhancing appeal and establishing symmetry of the concepts. Consequences for interpretation and sensitivity analysis are discussed. The ideas are illustrated in three sets of data.
Variable selection in partially linear wavelet models
Authors: Ding Huijuan , Claeskens Gerda , Jansen Maarten
Published: October 2011

Variable selection is fundamental in high-dimensional statistical modelling, including non-and semiparametric regression. However, little work has been done for variable selection in a partially linear model (PLM). We propose and study a unified approach via double penalized least squares, retaining good features of both variable selection and model estimation in the framework of PLM. The proposed method is distinguished from others in that the penalty functions combine the l1 penalty coming from wavelet thresholding in the non-parametric component with the l1 penalty from the lasso in the parametric component. Simulations are used to investigate the performances of the proposed estimator in various settings, illustrating its effectiveness for simultaneous variable selection as well as estimation.
Ethical and effective: Approaches to residential care for people with dementia
Authors: O'Sullivan Grace
Published: October 2011

New knowledge underpins calls for change in approaches to the care of people with dementia. Person-centred care is considered essential, whereas purpose-built facilities and environmental design are reported to enhance safety and to have a positive effect on behaviour. Research findings have highlighted the inappropriate use of antipsychotic drugs and there is debate about their value in ‘managing’ symptoms. This paper presents the combination of approaches used to enable residents of two secure dementia units to live life within their ability and without antipsychotic drugs. Essential to the success of the change process was staff education, knowledge of the person, a varied leisure activity programme and a supportive environment. Evidence of the positive difference these strategies made includes statistics that show a decline in falls and behavioural issues, and feedback from family members. In light of the evidence, this article posits that it is ethically wrong to give people with dementia antipsychotic medications because their behaviour is deemed to be unacceptable, when there are other viable options.
Sarcopenia and diabetes: pathogenesis and consequences
Authors: Khamseh Mohammad E , Malek Mojtaba , Aghili Rokhsareh , Emami Zahra
Published: October 2011

Sarcopenia, loss of muscle mass with age, is considered as a major cause of frailty and decreased independence in the elderly population. On the other hand, ageing is associated with an increase in prevalence of diabetes. In this review, we discuss the pathophysiological basis of sarcopenia and its relationship to oxidative stress and insulin resistance state, which contribute to development of glucose intolerance and type 2 diabetes. We will also discuss some ideas on the consequences and treatment of sarcopenia.
The prevalence of anaemia in diabetes with stage 3 chronic kidney disease: a retrospective analysis
Authors: Raja Umar Y , Chan Joseph , Radford Emma , Fallouh Bassam , Nair Harikrishnan , Dasgupta Indranil
Published: October 2011

The aim of this retrospective study was to assess the prevalence and causes of anaemia in patients with diabetes and stage 3 chronic kidney disease (CKD). Details of patients (n=3,499) with stage 3 CKD were extracted from the renal database of a hospital in Birmingham, UK, which serves a multiethnic population. Of the 2,438 patients with diabetes and stage 3 CKD, haemoglobin (Hb) measurements were available for 1,086 patients, of whom 289 were anaemic. Anaemia was defined as Hb <11.0 g/dl and subnormal Hb was defined as Hb <11.5 g/dl in women and <13.0 g/dl in men. The prevalence of anaemia was 31% among females and 21% among male patients. A ferritin level assessment had been undertaken in 34 of the 289 patients with anaemia (Hb <11.0 g/dl) and 23 of them showed iron deficiency (ferritin <100 µg/L). The prevalence of anaemia was higher in stage 3 CKD patients with diabetes (27%) than without diabetes (14%) and was 33% in patients of South Asian descent (p<0.0001 vs. no diabetes). There is a high prevalence of anaemia in people with diabetes and stage 3 CKD, and thus screening for anaemia should be part of their routine management.
Underweight is an important risk factor for coronary heart disease in the population of Ceningan Island, Bali
Authors: Suastika Ketut , Dwipayana Pande , Saraswati Made Ratna , Gotera Wira , Budhiarta Anak Agung Gde , Sutanegara Nengah Dwi , Gunadi Gusti Ngurah Putra , Nadha Ketut Badjra , Wita Wayan , Rina Ketut , Santoso Anwar , Soegondo Sidartawan , Kajiwara Naemi , Taniguchi Hiroshi
Published: October 2011

A study on the prevalence of coronary heart disease (CHD) and its risk factors in Ceningan Island was conducted. The prevalence of CHD was 11.5%. Older age (odds ratio, OR, 27.0), underweight (OR, 3.6), systolic hypertension (OR, 4.6), high total cholesterol (OR, 5.9), and high low-density lipoprotein cholesterol (OR, 3.1) were risk factors for a history of myocardial infarction (MI). By logistic regression analysis, only age ( B=3.937) and underweight ( B=1.275) consistently appeared to be risk factors for MI. The prevalence of CHD in the population was comparatively high.
Enhancement of Carboplatin- and Quercetin-Induced Cell Death by Roscovitine Is Akt Dependent and p53 Independent in Hepatoma Cells
Authors: Sharma Aanchal , Bhat Manoj Kumar
Published: October 2011

Purpose. Hepatocellular carcinoma (HCC) is a common malignancy worldwide and has an annual occurrence of one million new cases. Novel therapeutic strategies of increased efficacy in the treatment of HCC-bearing patients would certainly be helpful. Hence, the authors explored the effect of combination treatment of roscovitine with chemotherapeutic drugs or quercetin (Qctn) in hepatoma cells, HepG2 and Hep3B. Methods. Cell viability was assessed by MTT assay, cell growth assay, and nuclear morphological changes by DAPI staining. The altered expression of signaling proteins and apoptotic molecules was established by Western blotting. Results. Roscovitine pretreatment considerably enhanced the drugs and Qctn-induced cell death in HepG2 and Hep3B cells. The exploratory studies revealed that augmented cell killing in HepG2 and Hep3B was mediated via Akt pathway and was independent of p53. pAkt was found to be significantly downregulated in combination treatment of roscovitine with carboplatin or Qctn. Corresponding to reduced expression of pAkt, the downstream molecules Bcl-2 and proactive forms of caspase 9 and caspase 3 were also downregulated indicating apoptosis. Conclusions. The present study reports for the first time, in hepatoma cells, the potentiation of carboplatin- and Qctn-induced cell death by the cell cycle inhibitor roscovitine. Roscovitine can thus be considered as a potential therapeutic target in combination with chemotherapeutic drugs or Qctn for treatment of HCC.
Challenges in the design and implementation of the Multicenter Uveitis Steroid Treatment (MUST) Trial – lessons for comparative effectiveness trials
Authors: Holbrook Janet T , Kempen John H , Prusakowski Nancy A , Altaweel Michael M , Jabs Douglas A ,   for The Multicenter Uveitis Steroid Treatment (MUST) Trial Research Group
Published: October 2011

Background Randomized clinical trials (RCTs) are an important component of comparative effectiveness (CE) research because they are the optimal design for head-to-head comparisons of different treatment options.

Purpose To describe decisions made in the design of the Multicenter Uveitis Steroid Treatment (MUST) Trial to ensure that the results would be widely generalizable.

Methods Review of design and implementation decisions and their rationale for the trial.

Results The MUST Trial is a multicenter randomized controlled CE trial evaluating a novel local therapy (intraocular fluocinolone acetonide implant) versus the systemic therapy standard of care for noninfectious uveitis. Decisions made in protocol design in order to broaden enrollment included allowing patients with very poor vision and media opacity to enroll and including clinical sites outside the United States. The treatment protocol was designed to follow standard care. The primary outcome, visual acuity, is important to patients and can be evaluated in all eyes with uveitis. Other outcomes include patient-reported visual function, quality of life, and disease and treatment related complications.

Limitations The trial population is too small for subgroup analyses that are of interest and the trial is being conducted at tertiary medical centers.

Conclusion CE trials require greater emphasis on generalizability than many RCTs but otherwise face similar challenges for design choices as any RCT. The increase in heterogeneity in patients and treatment required to ensure generalizability can be balanced with a rigorous approach to implementation, outcome assessment, and statistical design. This approach requires significant resources that may limit implementation in many RCTs, especially in clinical practice settings.
Planning nurse staffing: are we willing and able?
Authors: Ball Jane , Catton Howard
Published: October 2011

Academic research and public enquiries demonstrate the link between adequate staffing levels and patients’ experiences and outcomes. Health care providers have a legal duty to ensure (and demonstrate to care regulators) that staffing levels are safe. Yet evidence of effective workforce planning, locally or nationally, is scarce. A plethora of tools exist to help employers to determine nurse staffing required. Although not perfect, the technical resource is none the less available to support planning, but are we willing to use it? In England the different systems have not been reviewed or tested and there is no consensus about the best approach to use. This paper asserts that decisions about current and future configurations of the nursing workforce are currently taken in a data vacuum. Fundamental aspects of nurse deployment – the proportion of registered nurses, the ratio of patients to nurse – are not systematically captured or recorded, either nationally or locally. We argue that a first step in planning is to establish this baseline. We need data on nursing inputs to relate to the growing body of data on patient outcomes, to enable managers and policy makers to understand the efficacy of current workforce configurations and inform future plans.
Assessing mechanical loading regimes and fatigue life of marine power cables in marine energy applications
Authors: Thies P R , Johanning L , Smith G H
Published: October 2011

Reliable marine power cables are imperative for the cost-effective operation of marine energy conversion systems. There is considerable experience with marine power cables under static and dynamic load conditions but the loading regimes for floating marine energy converters are not well understood, due to a lack of field experience. This paper aims to assess mechanical load conditions and failure modes for a dynamic power cable that is connected to a floating wave energy converter. The applied approach combines experimental tank test data with numerical modelling and site-specific wave characteristics to identify maximum load points and to quantify the fatigue life. The effect of varying wave parameters on maximum loads and fatigue cycles is investigated and results are presented for two common umbilical configurations: catenary and lazy wave. In situations with limited field experience, the presented approach provides a tool to determine if critical components are fit for purpose and to assess the expected level of reliability prior to deployment. The cable conductor’s fatigue life is estimated for the lazy wave configuration and highlights component fatigue failure as a major concern that must be addressed in floating marine energy applications.
Effects of lithium on lipopolysaccharide-induced inflammation in rat primary glia cells
Authors: Nahman Sigalit , Belmaker RH , Azab Abed N
Published: October 2011

Lithium is the gold-standard treatment for bipolar disorder, a severe mental illness. A large body of evidence suggests that inflammation plays a role in the pathogenesis of bipolar disorder and that mood stabilizers exhibit anti-inflammatory properties. However, contradicting findings have also been reported. In this study, we examined the effects of lithium on LPS-induced inflammation in rat primary glia cells. Cells were pre-treated with lithium (1 or 10 mM) for 6 or 24 h, after which, inflammation was induced by the addition of LPS (for another 18 h) to the culture medium. Thereafter, medium was collected and cells were harvested for further analyses. Levels of TNF-α, IL1-β and PGE2 were determined by ELISA and NO levels by the Griess reaction assay. Expression levels of cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) were examined by Western blot analysis. We found that pre-treatment with lithium 10 mM (but not 1 mM) significantly reduced LPS-induced secretion of TNF-α, IL1-β, PGE2 and NO. In addition, lithium significantly reduced the expression of COX-2 and iNOS. These findings indicate that lithium exhibits a potent anti-inflammatory effect. However, it’s important to emphasize that this effect was obtained mainly under treatment with an extra-therapeutic concentration of the drug.