bluuebunny/crossref_metadata_2025 huggingface dataset:
Egr1 regulates the coordinated expression of numerous EGF receptor target genes as identified by ChIP-on-chip
Authors: Arora Shilpi , Wang Yipeng , Jia Zhenyu , Vardar-Sengul Saynur , Munawar Ayla , Doctor Kutbuddin S , Birrer Michael , McClelland Michael , Adamson Eileen , Mercola Dan
Published: November 2008

Background

UV irradiation activates the epidermal growth factor receptor, induces Egr1 expression and promotes apoptosis in a variety of cell types. We examined the hypothesis that Egr1 regulates genes that mediate this process by use of a chip-on-chip protocol in human tumorigenic prostate M12 cells.

Results

UV irradiation led to significant binding of 288 gene promoters by Egr1. A major functional subgroup consisted of apoptosis related genes. The largest subgroup of 24 genes belongs to the epidermal growth factor receptor-signal transduction pathway. Egr1 promoter binding had a significant impact on gene expression of target genes. Conventional chromatin immunoprecipitation and quantitative real time PCR were used to validate promoter binding and expression changes. Small interfering RNA experiments were used to demonstrate the specific role of Egr1 in gene regulation. UV stimulation promotes growth arrest and apoptosis of M12 cells and our data clearly show that a downstream target of the epidermal growth factor receptor, namely Egr1, mediates this apoptotic response. Our study also identified numerous previously unknown targets of Egr1. These include FasL, MAX and RRAS2, which may play a role in the apoptotic response/growth arrest.

Conclusions

Our results indicate that M12 cells undergo Egr1-dependent apoptotic response upon UV stimulation and led to the identification of downstream targets of Egr1, which mediate epidermal growth factor receptor function.
Techniques, analysis, and noise in a Salt Lake Valley 4D gravity experiment
Authors: Gettings Paul , Chapman David S. , Allis Rick
Published: November 2008

Repeated high-precision gravity measurements using an automated gravimeter and analysis of time series of [Formula: see text] samples allowed gravity measurements to be made with an accuracy of [Formula: see text] or better. Nonlinear instrument drift was removed using a new empirical staircase function built from multiple station loops. The new technique was developed between March 1999 and September 2000 in a pilot study conducted in the southern Salt Lake Valley along an east-west profile of eight stations from the Wasatch Mountains to the Jordan River. Gravity changes at eight profile stations were referenced to a set of five stations in the northern Salt Lake Valley, which showed residual signals of [Formula: see text] in amplitude, assuming a reference station near the Great Salt Lake to be stable. Referenced changes showed maximum amplitudes of [Formula: see text] through [Formula: see text] at profile stations, with minima in summer 1999, maxima in winter 1999–2000, and some decrease through summer 2000. Gravity signals were likely a composite of production-induced changes monitored by well-water levels, elevation changes, precipitation-induced vadose-zone changes, and local irrigation effects for which magnitudes were estimated quantitatively.
Multinational Study of Cancer Patients and Their Children: Factors Associated With Family Functioning
Authors: Schmitt Florence , Piha Jorma , Helenius Hans , Baldus Christiane , Kienbacher Christian , Steck Barbara , Thastum Mikael , Watson Maggie , Romer Georg
Published: November 2008

Purpose

This study examined factors associated with family functioning in cancer patients’ families with dependent children.

Patients and Methods

A sample of 381 families (639 parents and 489 children) was recruited simultaneously in six European countries. Patients and family members completed a background questionnaire, the Family Assessment Device (FAD), the Beck Depression Inventory, and the short form version of the Medical Outcomes Health Survey. Descriptive statistics and a multilevel model that allowed a multi-informant design were used. Analyses were carried out with all participants, and separately with parent-rated and children-rated FAD scores.

Results

In descriptive analyses, children reported more impairment in family functioning than parents, but the difference was not significant. Depression prevalence was 35% for ill mothers and 28% for ill fathers. In the multilevel analyses with all participants (ie, adults and children) the ill parent's depression was significantly associated with impaired family functioning on five of seven FAD subscales. In analyses with only children, the perception of impairment of family functioning was not associated with parental depression. Additionally, poorer physical status of the ill parent was significantly associated with impairment on roles and communication.

Conclusion

The ill parent's depression was the most significant factor associated with impairment in family functioning. Screening for depression, active diagnostics, and appropriate treatment of cancer patient's and partner's depression may be important to protect their children from mental disorders. Therefore, support systems need to be more family-oriented and child-centered in their approaches to cancer psychosocial care.
Impact of Caring for a Child With Cancer on Parents’ Health-Related Quality of Life
Authors: Klassen Anne F. , Klaassen Robert , Dix David , Pritchard Sheila , Yanofsky Rochelle , O'Donnell Maureen , Scott Amie , Sung Lillian
Published: November 2008

Purpose

To compare the health-related quality of life (QOL) of parents of children who are undergoing treatment for cancer with that of Canadian population norms and to identify important parent and child predictors of parental QOL.

Patients and Methods

A total of 411 respondents of 513 eligible parents were recruited from five pediatric oncology centers in Canada between November 2004 and February 2007. Parents were asked to complete a questionnaire booklet that included a measure of adult QOL (SF-36), a measure of child health status (functional status IIR), and questions to assess health-promoting self-care actions (eg, sleep, diet, and exercise habits) and characteristics of the child with cancer (eg, relapse status, time since diagnosis, prognosis, treatment intensity).

Results

Compared with population norms, parents of children with cancer reported poorer physical and psychosocial QOL in all psychosocial domains (effect sizes range, −0.71 to −1.58) and in most physical health domains (effect sizes range, −0.08 to −0.63). Parent characteristics associated with better parental QOL included better eating, exercise and sleep habits, younger age, and higher income. Child characteristics associated with better parental QOL included better child health status (functional status IIR scores), lower treatment intensity, and longer time since diagnosis.

Conclusion

Parents of children with cancer report poorer QOL compared with population norms. Interventions directed at parents should be included as part of the treatment plan for a child with cancer. Modifiable variables associated with poorer parental QOL, such as sleep quality and diet and exercise habits, indicate those parents most likely to experience poor QOL and may be potential areas for intervention.
Depression in Family Caregivers of Cancer Patients: The Feeling of Burden As a Predictor of Depression
Authors: Rhee Young Sun , Yun Young Ho , Park Sohee , Shin Dong Ok , Lee Kwang Mi , Yoo Han Jin , Kim Jeong Hwa , Kim Soon Ok , Lee Ran , Lee Youn Ok , Kim Nam Shin
Published: November 2008

Purpose

The purpose of this study was to explore the prevalence of and to identify the predictors of depression in family caregivers of cancer patients.

Patients and Methods

We enrolled 310 caregivers of cancer patients from the National Cancer Center, Korea, on this study and obtained demographic information for both patients and caregivers. To assess caregiver depression and its predictors, we used the Beck Depression Inventory (BDI), the Caregiver Quality of Life Index–Cancer, and the Family Impact Questionnaire. We used logistic regression analysis to identify independent predictors of caregiver depression.

Results

The majority (67%) of caregivers had high depression scores (BDI > 13), and 35% had very high depression scores (BDI > 21). In a multiple logistic regression model, caregivers who were women, the spouse of the patient, in poor health, feeling burdened, adapting poorly, unable to function normally, or caring for a patient with poor Eastern Cooperative Oncology Group performance status were more likely to experience depression (P < .01 for all values).

Conclusion

Depression was highly prevalent among cancer patient family caregivers, and care burden was its best predictor. Interventions aimed at reducing the psychiatric effects of cancer should focus not only on the patient but also on the caregiver.
What Are Terminally Ill Cancer Patients Told About Their Expected Deaths? A Study of Cancer Physicians’ Self-Reports of Prognosis Disclosure
Authors: Daugherty Christopher K. , Hlubocky Fay J.
Published: November 2008

Purpose

Little is known about how physicians discuss prognosis with terminally ill cancer patients. Thus, we sought to obtain cancer physicians’ self-reports of their prognosis communication practices.

Methods

A survey seeking self-reports regarding prognosis communication with their terminally ill cancer patients was mailed to a systematic sample of medical oncologists in the United States.

Results

Of 1,137 physicians, 729 completed and returned surveys (64% response rate). Median age of respondents was 51 years (range, 33 to 80 years); 82% were men. Respondents had practiced cancer care for a median of 18 years (range, 1.5 to 50 years) and reported seeing a median of 60 patients per week (range, 0 to 250 patients per week). Although 98% said their usual practice is to tell terminally ill patients that they will die, 48% specifically described communicating terminal prognoses to patients only when specific preferences for prognosis information were expressed. Forty-three percent said they always or usually communicate a medical estimate of time as to when death is likely to occur, and 57% reported sometimes, rarely, or never giving a time frame. Seventy-three percent said prognosis communication education was either absent or inadequate during their training, and 96% believed it should be part of cancer care training.

Conclusion

Medical oncologists report routinely informing their terminally ill patients that they will die. However, they are divided in describing themselves as either always discussing a terminal prognosis or doing so if it is consistent with their patients’ preferences for prognostic information. Most medical oncologists say they do not routinely communicate an estimated survival time to their patients.
Cause-Specific Survival for Women Diagnosed With Cancer During Pregnancy or Lactation: A Registry-Based Cohort Study
Authors: Stensheim Hanne , Møller Bjørn , van Dijk Tini , Fosså Sophie D.
Published: November 2008

Purpose

To assess if cancers diagnosed during pregnancy or lactation are associated with increased risk of cause-specific death.

Patients and Methods

In this population-based cohort study using data from the Cancer Registry and the Medical Birth Registry of Norway, 42,511 women, age 16 to 49 years and diagnosed with cancer from 1967 to 2002, were eligible. They were grouped as not pregnant (reference), pregnant, or lactating at diagnosis. Cause-specific survival for all sites combined, and for the most frequent malignancies, was investigated using a Cox proportional hazards model. An additional analysis with time-dependent covariates was performed for comparison of women with and without a postcancer pregnancy. The multivariate analyses were adjusted for age at diagnosis, extent of disease, and diagnostic periods.

Results

For all sites combined, no intergroup differences in cause-specific death were seen, with hazard ratio (HR) of 1.03 (95% CI, 0.86 to 1.22) and HR 1.02 (95% CI, 0.86 to 1.22) for the pregnant and lactating groups, respectively. Patients with breast (HR, 1.95; 95% CI, 1.36 to 2.78) and ovarian cancer (HR, 2.23; 95% CI, 1.05 to 4.73) diagnosed during lactation had an increased risk of cause-specific death. Diagnosis of malignant melanoma during pregnancy slightly increased this risk. For all sites combined, the risk of cause-specific death was significantly decreased for women who had postcancer pregnancies.

Conclusion

In general, the diagnosis of most cancer types during pregnancy or lactation does not increase the risk of cause-specific death. Breast and ovarian cancer diagnosed during lactation represents an exception. We confirmed the “healthy mother effect” for women with a postcancer pregnancy.
Utilitarianism without Utility: A Missed Opportunity in Alfred Marshall's Theory of Market Choice
Authors: Dardi Marco
Published: November 2008

This article argues that Marshall's theory of market choice was originally elaborated within the classic framework of the use value/exchangeable value dichotomy, with reference to a version of utilitarianism that did not assume measurable utility. The key concepts were those of marginal transaction and consumer surplus or rent, both of which were expressed exclusively in terms of money transfers. Later on, Marshall moved toward an explicitly utilitarian framework by emphasizing the marginal utility of money, possibly because he had stumbled on the problem of the determinateness of marginal demand prices. The article shows that, by moving in this direction, Marshall committed himself to a standpoint that undermined the generality of his approach to consumer behavior and obscured his promising ideas concerning interpersonal comparisons of welfare. It is also argued that this move was actually unnecessary, as the early framework could have enabled Marshall to deal with the problem of determinateness in less restrictive terms.
Transnationalism and Homophile Political Culture in the Postwar Decades
Authors: Churchill David S.
Published: November 2008

This article grows out of a larger project on homophile internationalism that linked Europe and North America organizations, activists and writing during the post-war decades. More than just participating in a North Atlantic exchange, these homophile activists had a global vision, one that sought to uncover, explore and archive same-sex intimacies worldwide. Utilizing travel writing, ethnographic studies and personal memoirs homophiles produced a popular anthropological account of homosexuality, one they implicitly linked to Cold War human rights discourse, liberal law reform, and normative social claims.
Situating “FLUIDITY”
Authors: Davis Erin Calhoun
Published: November 2008

Drawing on Butler's theory of gender performativity, which conceptualizes the discursive production of the gendered subject and the corresponding “constitutive instabilities” of such reiterative practices, I provide an empirical sociological examination of how individuals negotiate potentially unintelligible identities in their daily lives and the extent to which these practices call into question the conceptual dichotomization of stability and fluidity. While transsexed bodies, histories, and identities may “exceed” the limits of intelligibility, trans individuals are engaged in the process of meaning making—creating coherence both for themselves and for others. The present theorizing of (trans)gender identification has not fully explored the interaction among social expectations, individuals' attempts to be credible, and the structural limitations on intelligible gender identifications. In addition, despite theoretical arguments resting on the compulsory, regulatory nature of gender regimes, gender fluidity is often situated as counter to such regulation. By exploring the negotiated identifications of transsexed respondents across different interactional spaces and the structural rules and norms which frame such presentation choices, this article theorizes the contextual regulation of (trans)gender diversity and the corresponding production of situated identification. Further, in examining this negotiation, the concept of fluidity is interrogated in order to complicate the analytic dualism of fluidity/stability and the corresponding dichotomous positioning of transsexed individuals as either blurring or reifying the boundaries of the gender binary.
Queer (AND) Animal Theories
Authors: McHugh Susan
Published: November 2008

Nonhuman nonheteronormativity presents a profound challenge not just to identity forms but more importantly to disciplinary habits of thinking of human subjectivity as the default form of social agency. To elaborate this point, this essay surveys how some recent books, including Roughgarden's Evolution's Rainbow: Diversity, Gender, and Sexuality in Nature and People, Donna Haraway's When Species Meet, Alice A. Kuzniar's Melancholy's Dog, and Jens Rydström's Sinners and Citizens: Bestiality and Homosexuality in Sweeden, 1889-1950, take as their subjects intimacies that belie hetero/homosexual along with non/human binaries. Grounding queer theory in a cross-species continuum is not the overall purpose of any of these texts, but an effect produced through the alignment of these authors' very different examinations of sex relations as shared by social animals. Ranging from the bizarre (fish threesomes) to the raunchy (bestiality in the cowshed), and even more ordinary combinations of both (dogs' dry-humping), the forms of sociality accruing in these discussions lay foundations for new biopolitical (as opposed to disciplinary) knowledges, prompting further inquiry into what happens to all of us when animals do it unlike they do on the Discovery Channel.
Re-cold expansion process simulation to impart the residual stresses around fastener holes in 6061 A-T6 aluminium alloy
Authors: Jang J S , Kim D W
Published: November 2008

Cold expansion processes are widely used in aerospace structures to eliminate or delay fatigue crack nucleation and to improve fatigue life. Fastener holes, in which the fatigue cracks initiate from stress concentrations, are plastically expanded using a mandrel pulled through the hole. Cold expansion technology has been applied to enhance low-cycle fatigue performance in repair as well as production applications. Repair of aircraft structures is a key component to extend aircraft service life. Re-cold expansion process conditions such as the degree of cold expansion should be determined to impart the beneficial compressive residual stresses around the holes under tensile loadings.

In this paper, a process simulation using three-dimensional finite element analysis is conducted to determine the residual stress imparted by re-cold expansion in the fastener holes under the external loading conditions. Three levels of re-cold expansion under three external loading levels are performed in this numerical investigation. It is shown that the re-cold expansion process with at least 6 per cent of the degree of cold expansion imparts deep residual stresses around the hole so that the resulting stress levels on the hole entry side remain compressive under applied external stress levels between 100 and 200 MPa. In addition, residual stress redistribution under various applied external stresses is discussed.
Analysis of accuracy of high-aspect-ratio holes generated using micro-electric discharge machining drilling
Authors: Puranik M S , Joshi S S
Published: November 2008

Micro-electric discharge machining (micro-EDM) has evolved as one of the prominent processes to generate high-aspect-ratio and accurate micro-structures in many industrial applications. This paper presents an extensive experimental analysis of the micro-EDM process to explore the relationship between accuracy as a function of depth of micro-holes drilled using micro-EDM drilling. It is shown that a depth of 5.0 mm can be achieved by a 200 μm diameter tool electrode while controlling the regular process parameters, but beyond this length, the process is governed by a number of derived phenomena such as secondary sparking, debris accumulation, etc. instead of the regular processing parameters. The optimum depth of the hole that could be achieved with a good accuracy i.e. a minimum oversize lies between 2.5 and 5.0 mm, the largest depth that could be achieved was 8.33 mm. The highest aspect ratio achieved in this experiment was 15.63.
An algorithm for the two-dimensional cutting problem of punched strips with blade length constraint
Authors: Cui Y , Zhang X , Wang Q
Published: November 2008

This paper presents an algorithm for generating optimal T-shaped cutting patterns of punched strips. A strip contains only items of the same type. The stock plate is divided into items in two stages. First a guillotine machine cuts the plate into strips, then a stamping press punches out the items from the strips. The blade length of the guillotine machine may be shorter than the plate length. The algorithm divides the plate into two segments. Each segment contains strips of the same direction. The strip directions of the two segments are perpendicular to each other. The algorithm uses dynamic programming techniques to determine the optimal strip layouts on segments of different lengths not longer than the blade length, considers all possible combinations of two segments, and selects the best pair as the optimal solution. The computational results indicate that the new algorithm is much more efficient than the existing algorithm.
A low-cost integrated positioning system for autonomous off-highway vehicles
Authors: Guo L-S , Zhang Q
Published: November 2008

This article reports a method for integrating a low-cost positioning system, constructed using a Garmin N17 global positioning system (GPS) and an integrated inertial sensor unit, consisting of three single-axis microelectromechanical system (MEMS) gyros and one triaxial MEMS accelerometer, for autonomous off-highway vehicle use. Based on a vehicle position—velocity—attitude (PVA) model, a data fusion algorithm was formulated to extract more accurate and reliable positioning information from the raw data sensed by the GPS and inertial sensor unit. The developed integrated positioning system (IPS) was evaluated on an agricultural utility vehicle on three different sites. A real-time kinematic (RTK) differential GPS unit, capable of providing 2–3cm dynamic positioning accuracy while the position dilution of precision is low enough, was installed on the test vehicle to provide accurate positioning references in those evaluation tests. Results obtained from those tests showed that, when the vehicle was travelling on paved roads near buildings and/or under the trees, the maximum positioning error of the developed IPS was 0.50m, and that this maximum error level was reduced to 0.30m when the vehicle was travelling in open fields. The IPS could provide a position update rate at 50Hz; even the GPS could provide only a 1Hz update rate. Test results also revealed that this system could continuously provide accurate position signals when the GPS signal is lost for up to 30s. This research verified that a low-cost IPS could provide satisfactory position information for autonomous off-highway vehicle uses.
Thermal model of a twin-tube cavitating shock absorber
Authors: Alonso M , Comas Á
Published: November 2008

An analytical method to quantify the damping force of a generic twin-tube shock absorber for an automobile is proposed. Previous models by the present authors have accounted for fluid compressibility, chamber deformation, and fluid cavitation. This paper extends the work to thermal effects which have now been included.

The variation in the force due to thermal effects caused by the energy dissipated within the damper is determined and the shock absorber temperature field is calculated. The results from the model are compared with those from simpler models (which do not include thermal effects) and are validated against the results from a real shock absorber.

In terms of damping force, a good correlation is obtained, while acceptable results are obtained for the temperature field calculation.
Factors influencing the burn rate characteristics of a spark ignition engine with variable valve timing
Authors: Bonatesta F , Shayler P J
Published: November 2008

The charge burn characteristics of a four-cylinder port-fuel-injected spark ignition engine fitted with a dual independent variable-valve-timing system have been investigated experimentally. The influence of valve timings on the flame development angle and the rapid burn angle is primarily associated with valve overlap values and internal gas recirculation. Conditions examined cover light to medium loads and engine speeds up to 3500r/min. As engine loads and speeds exceeded about 6bar net indicated mean effective pressure and 3000r/min respectively, combustion duration was virtually independent of the valve timing setting. At lower speeds and work output conditions, valve timing influenced burn angles through changes in dilution mass fraction, charge density, and charge temperature. Of these, changes in dilution mass fraction had the greatest influence. Increasing the dilution by increasing the valve overlap produced an increase in both burn angles. The effects of mean piston speed and spark timing have also been examined, and empirical expressions for the flame development and the rapid burn angles are presented.
Modelling for investigation of combustion and emission characteristics in a high-speed direct-injection diesel engine with light duty under various operating conditions
Authors: Kim H J , Ryu B W , Lee C S
Published: November 2008

A numerical study was conducted to investigate combustion and emission characteristics in a high-speed direct-injection engine with a common-rail injection system under various operating conditions. In order to analyse the combustion characteristics, several models were used in this study. They were the renormalization group k– ε model, the hybrid Kelvin—Helmholtz (wave) and the Rayleigh—Taylor model, the shell auto-ignition model, and the laminar and turbulent characteristic timescale combustion model. The prediction of exhaust emissions was conducted using nitrogen oxide NO x formation with an extended Zel'dovich mechanism and Hiroyasu soot formation with the Nagle—Strickland-Constable oxidation model respectively. Experimental combustion and emission characteristics were compared with calculated results under various operating conditions, such as injection timing, injection pressure, fuel mass, and engine speed. The calculated results show similar patterns to the experimental results in the cylinder pressure and the rate of heat release. In the emissions characteristics, NO x emission decreased as injection timing was retarded and the NO x and soot amounts increased with the increase in the injected fuel mass. The calculated soot trends for various injection timings showed different patterns from the experimental trends as the injection timing were retarded.
Development of an automotive rear subframe by the tube hydroforming process
Authors: Kim K J , Won S T , Lee Y H , Bae D S , Sung C W , Paik Y N
Published: November 2008

The automotive industry has shown a growing interest in tube hydroforming during recent years. The advantages of hydroforming (less thinning, a more efficient manufacturing process, etc.) can, for instance, be combined with the high strength of extra-high-strength steels, which are usually less formable, to produce structural automotive components which exhibit lower weight and improved service performance. Design and production of tubular components require knowledge about tube material and forming behaviour during hydroforming and how the hydroforming operation itself should be controlled. These issues are studied analytically in the present paper. In this study, the whole process of rear subframe parts development by tube hydroforming using steel material having a tensile strength of 440MPa is presented. At the part design stage, it requires a feasibility study and process design assisted by computer aided engineering to confirm hydroformability in detail. The effects of parameters such as internal pressure, axial feeding, and geometry shape in the automotive rear subframe by the hydroforming process were carefully investigated. The overall possibility of hydroformable rear subframe parts could be examined by cross-sectional analyses. Moreover, it is essential to ensure the formability of tube material on every forming step such as pre-bending and hydroforming. In addition, all the components of a prototyping tool are designed and interference with a press is examined from the point of geometry and thinning.
Development of a direct-injection stratified-charge methanol engine
Authors: Li B-Z , Liu S-H , Nong J-J , Gong Y-F , Zhou L-B
Published: November 2008

On the basis of the wall-guided, spray-guided, and air-guided technologies related to gasoline direct-injection spark-ignition (DISI) engines, a complex-guided stratified-charge combustion system for a methanol DISI engine was developed. The test engine was a retrofitted four-cylinder diesel engine. The key parameters were optimized numerically and experimentally, such as the location of the swirl deflector, the spatial location of spray, the swirl ratio, the injection and ignition timings, and the needle valve opening pressure. The results show that the direct-injection stratified-charge (DISC) methanol engine can work with an excessive air ratio λ as high as 2.23, and its brake thermal efficiency reaches 29.7 per cent at a speed of 1500r/min, and a brake mean effective pressure of 0.45MPa. The DISC methanol engine exhibits relatively good performance with little cyclic variations, although it is sensitive to induction swirl.

The test results indicate that the matching principle is successful. The developed DISC methanol engine can run under variable induction swirl to meet the requirement of stratification combustion under different engine speed operating conditions.
An experimental investigation on performance, emissions, and combustion in a manifold injection for different exhaust gas recirculation flowrates in hydrogen—diesel dual-fuel operations
Authors: Saravanan N , Nagarajan G
Published: November 2008

Hydrogen is receiving considerable attention as an alternative fuel to replace the rapidly depleting petroleum-based fuels. Its clean burning characteristics help to meet the stringent emission norms. In this experimental investigation a single-cylinder diesel engine was converted to operate in hydrogen—diesel dual-fuel mode. Hydrogen was injected in the intake manifold and the diesel was injected directly inside the cylinder. The injection timing and the injection duration of hydrogen were optimized on the basis of performance and emissions. Best results were obtained with hydrogen injection at gas exchange top dead centre with an injection duration of 30° crank angle. The flowrate of hydrogen was optimized as 7.5l/min with optimized injection timing and duration. The optimized exhaust gas recirculation (EGR) flowrate was 20 per cent at 75 per cent load. The optimized timings were chosen on the basis of performance, emission, and combustion characteristics. The EGR technique was adopted in the hydrogen—diesel dual-fuel mode by varying the EGR flowrate from 0 per cent to 25 per cent in steps of 5 per cent. The maximum quantity of exhaust gases recycled during the test was 25 per cent (up to 75 per cent load); beyond that unstable combustion was observed with an increase in smoke. The brake thermal efficiency with 20 per cent EGR decreases by 9 per cent compared with diesel. The nitrogen oxide (NO x) emission in hydrogen manifold injection decreases by threefold with 20 per cent EGR operation at full load. The NO x emission tends to reduce drastically with increase in the EGR percentage at all load conditions owing to the increase in heat capacity of the exhaust gases. The smoke decreases by 80 per cent in the dual-fuel operation compared with diesel at 75 per cent load.
Studying the effects of hydrogen addition on the second-law balance of a biogas-fuelled spark ignition engine by use of a quasi-dimensional multi-zone combustion model
Authors: Rakopoulos C D , Michos C N , Giakoumis E G
Published: November 2008

Although a first-law analysis can show the improvement that hydrogen addition impacts on the performance of a biogas-fuelled spark-ignition (SI) engine, additional benefits can be revealed when the second law of thermodynamics is brought into perspective. It is theoretically expected that hydrogen enrichment in biogas can increase the second-law efficiency of engine operation by reducing the combustion-generated irreversibilities, because of the fundamental differences in the mechanism of entropy generation between hydrogen and traditional hydrocarbon combustion. In this study, an experimentally validated closed-cycle simulation code, incorporating a quasi-dimensional multi-zone combustion model that is based on the combination of turbulent entrainment theory and flame stretch concepts for the prediction of burning rates, is further extended to include second-law analysis for the purpose of quantifying the respective improvements. The analysis is applied for a single-cylinder homogeneous charge SI engine, fuelled with biogas—hydrogen blends, with up to 15 vol% hydrogen in the fuel mixture, when operated at 1500r/min, wide-open throttle, fuel-to-air equivalence ratio of 0.9, and ignition timing of 20° crank angle before top dead centre. Among the major findings derived from the second-law balance during the closed part of the engine cycle is the increase in the second-law efficiency from 40.85 per cent to 42.41 per cent with hydrogen addition, accompanied by a simultaneous decrease in the combustion irreversibilities from 18.25 per cent to 17.18 per cent of the total availability of the charge at inlet valve closing. It is also illustrated how both the increase in the combustion temperatures and the decrease in the combustion duration with increasing hydrogen content result in a reduction in the combustion irreversibilities. The degree of thermodynamic perfection of the combustion process from the second-law point of view is quantified by using two (differently defined) combustion exergetic efficiencies, whose maximum values during the combustion process increase with hydrogen enrichment from 49.70 per cent to 53.45 per cent and from 86.01 per cent to 87.33 per cent, respectively.
In situ and on-demand lubrication by tribo-coating for space applications
Authors: Adachi K , Kato K
Published: November 2008

A self-restoring lubrication system with an in situ and on-demand controllable lubrication method is required to improve reliability and to overcome unexpected tribological problems in space.

A new type of lubrication method called ‘tribo-coating’, which forms a thin lubricious film (tribo-coating film) in nanometre-scale by vacuum deposition during sliding, is promising as a required lubrication method for future space systems.

This method gives the unique advantage of excellent tribological performance of friction coefficient of<0.02 in sliding contacts and 0.002 in ball bearings. Its possibility as a self-restored lubrication system with in situ and on-demand control of lubrication for ball bearings in vacuum systems is clarified.
Analysis Method of Trace Compounds by Hollow-fiber Liquid-phase Microextraction with Electric Field Enhancement of Mass Transfer
Authors: Guo Yugao , Yu Yuzan , Liu Xiujun , Tang Enqi
Published: November 2008

A novel electric-field-enhanced liquid-phase microextraction system based on hollow fiber membrane has been developed. By introducing the radially enhancing electric field into this system, it is feasible to accelerate the mass-transfer rate of analyte and shorten the equilibrium time. In the process, the extract time was less than 4 min, which is much less than that of traditional liquid-phase microextraction. Further study is in progress.
Direct Preparation and Size Control of Highly Crystalline Cubic ITO Nanoparticles in a Concentrated Solution System
Authors: Endo Yosuke , Sasaki Takafumi , Kanie Kiyoshi , Muramatsu Atsushi
Published: November 2008

Highly crystalline cubic indium tin oxide (ITO) nanoparticles with narrow size distribution were successfully prepared directly in one step from a mixed solution of indium and tin salts by a solvothermal method with ethylene glycol as solvent. Also, size was easily manipulated by changing conditions, such as aging period and sodium hydroxide concentration.
Resonance-enhanced Multiphoton Ionization Spectroscopy of the S1–S0 Transition of Benzo[e]pyrene for Real-time Analysis
Authors: Misawa Kentaro , Matsumoto Jun , Tsuji Norihiro , Matsuzaki Yoichi , Hayashi Shun-ichi , Fujii Masaaki
Published: November 2008

The electronic spectrum of benzo[e]pyrene (BeP) was recorded using resonance-enhanced multi-photon ionization (REMPI) spectroscopy. A number of bands were observed and assigned to the origin band and vibronic bands of the S1–S0 transition. Ab initio calculations were performed to assign the vibrational structures in S1. The origin band of BeP is well separated in energy from the origin band of benzo[a]pyrene (BaP), an isomer of BeP, and so BeP and BaP can be readily distinguished by the REMPI method, despite having the same mass.
Siloxane-crosslinked Polysaccharide Nanogels for Potential Biomedical Applications
Authors: Yamane Setsuko , Sasaki Yoshihiro , Akiyoshi Kazunari
Published: November 2008

The hybrid nanogels were prepared by condensation of silanol groups grafted to cholesterol-bearing pullulan at ambient temperature and pH without any catalysts or organic solvents. This is a new method for preparation of organic–inorganic hybrid nanogels with dual network structures of both chemically crosslinked points with siloxane bonds and physically crosslinked hydrophobic association points.
Conformation of the signal recognition particle in ribosomal targeting complexes
Authors: Buskiewicz Iwona A. , Jöckel Johannes , Rodnina Marina V. , Wintermeyer Wolfgang
Published: November 2008

The bacterial signal recognition particle (SRP) binds to ribosomes synthesizing inner membrane proteins and, by interaction with the SRP receptor, FtsY, targets them to the translocon at the membrane. Here we probe the conformation of SRP and SRP protein, Ffh, at different stages of targeting by measuring fluorescence resonance energy transfer (FRET) between fluorophores placed at various positions within SRP. Distances derived from FRET indicate that SRP binding to nontranslating ribosomes triggers a global conformational change of SRP that facilitates binding of the SRP receptor, FtsY. Binding of SRP to a signal-anchor sequence exposed on a ribosome-nascent chain complex (RNC) causes a further change of the SRP conformation, involving the flexible part of the Ffh(M) domain, which increases the affinity for FtsY of ribosome-bound SRP up to the affinity exhibited by the isolated NG domain of Ffh. This indicates that in the RNC–SRP complex the Ffh(NG) domain is fully exposed for binding FtsY to form the targeting complex. Binding of FtsY to the RNC–SRP complex results in a limited conformational change of SRP, which may initiate subsequent targeting steps.
A critical assessment of the utility of protein-free splicing systems
Authors: Smith Duncan J. , Konarska Maria M.
Published: November 2008

U2 and U6 snRNAs form part of the catalytic spliceosome and represent strong candidates for components of its active site. Over the past decade it has become clear that these snRNAs are capable of catalyzing several different chemical reactions, leading to the widespread conclusion that the spliceosome is a ribozyme. Here, we discuss the advances in both protein-free and fully spliceosomal systems that would be required to conclude that the reactions observed to be catalyzed by protein-free snRNAs are related to splicing and question the reliability of snRNA-only systems as tools for mechanistic splicing research.
The 5′ external transcribed spacer in mouse ribosomal RNA contains two cleavage sites
Authors: Kent Tatyana , Lapik Yevgeniya R. , Pestov Dimitri G.
Published: November 2008

The 5′ external transcribed spacer (5′ETS) is critical for 18S rRNA formation and is the longest noncoding region in a ribosomal RNA transcript. Here we show that processing in mouse 5′ETS involves two cleavage events. Processing at site A′ corresponds to the previously described “primary cleavage,” which precedes other processing steps. Processing at the novel site A0 occurs 1 kb downstream from A′ yielding two new rRNA precursors: 43S and 29S. The excised 5′-A′ and A′-A0 fragments are rapidly degraded under normal conditions. Depletion of the exosome component EXOSC10/PM-Scl100 (ortholog of yeast Rrp6p) results in a strong accumulation of the A′-A0 spacer fragment in mouse cells. We discuss the finding of a second processing site in mammalian 5′ETS in relation to the involvement of the U3 snoRNA in pre-rRNA processing and present a revised map of the mouse 18S rRNA processing pathway.
Purchasing, Pricing, and Quick Response in the Presence of Strategic Consumers
Authors: Cachon Gérard P. , Swinney Robert
Published: November 2008

We consider a retailer that sells a product with uncertain demand over a finite selling season. The retailer sets an initial stocking quantity and, at some predetermined point in the season, optimally marks down remaining inventory. We modify this classic setting by introducing three types of consumers: myopic consumers, who always purchase at the initial full price; bargain-hunting consumers, who purchase only if the discounted price is sufficiently low; and strategic consumers, who strategically choose when to make their purchase. A strategic consumer chooses between a purchase at the initial full price and a later purchase at an uncertain markdown price. In equilibrium, strategic consumers and the retailer make optimal decisions given their rational expectations regarding future prices, availability of inventory, and the behavior of other consumers. We find that the retailer stocks less, takes smaller price discounts, and earns lower profit if strategic consumers are present than if there are no strategic consumers. We find that a retailer should generally avoid committing to a price path over the season (assuming such commitment is feasible)—committing to a markdown price (or to not mark down at all) is often too costly (inventory may remain unsold) even in the presence of strategic consumers; the better approach is to be cautious with the initial quantity and then mark down optimally. Furthermore, we discuss the value of quick response (the ability to procure additional inventory after obtaining updated demand information, albeit at a higher unit cost than the initial order). We find that the value of quick response to a retailer is generally much greater in the presence of strategic consumers than without them: on average 67% more valuable and as much as 558% more valuable in our sample. In other words, although it is well established in the literature that quick response provides value by allowing better matching of supply with demand, it provides more value, often substantially more value, by allowing a retailer to control the negative consequences of strategic consumer behavior.
Spillover Asymmetry and Why It Matters
Authors: Knott Anne Marie , Posen Hart E. , Wu Brian
Published: November 2008

Although spillovers are a crucial factor in determining the optimal environment for innovation, there is no consensus regarding their impact on firm behavior. One reason for this may be that models differ in their assumptions for the functional form of the spillover pool. In industrial organization and economic geography, for example, the predominant convention is that all innovation within an industry/region contributes to a spillover pool that has a common value for all firms. An alternative convention prevalent in endogenous growth and evolutionary economics is that spillovers have directionality—the size of the relevant pool differs across firms.

Knowing the correct functional form may facilitate theoretical consensus, either analytically (by modifying models' assumptions) or empirically (by supporting a critical test of competing theories). We characterize and test the functional form of spillover pools for efficiency-enhancing innovation across 50 markets in the banking industry. Our results in that setting are consistent with expectations for asymmetric spillovers but inconsistent with expectations for pooled spillovers.
Hybrid Films Consisting of a Clay and a Diacetylenic, Two-Photon Absorptive Dye
Authors: Suzuki Yasutaka , Hirakawa Shoichiro , Sakamoto Yusuke , Kawamata Jun , Kamada Kenji , Ohta Koji
Published: November 2008

Hybrid films consisting of Sumecton SA smectite (SSA) and a diacetylenic two-photon absorptive dye; 1,4-bis(2,5-dimethoxy-4-{2-[4-(N-methyl)pyridinium]ethenyl}phenyl) butadiyne triflate (MPPBT) were fabricated. The MPPBT-clay composites were prepared by the cation exchange method in a dimethylsulfoxide (DMSO)-water mixed solvent. A low-light-scattering film, suitable for use in optical devices, was obtained by filtration of the dispersion of the MPPBT-clay composites. Estimation of the two-photon absorption cross-section (σ(2)) by means of the open-aperture Z-scan technique was performed using the present film. The σ(2) value of MPPBT in the film fabricated at the MPPBT loading levels vs. 20% cation exchange capacity was 1030 GM (1 GM= 1 × 1050 cm4 s photon−1 molecule−1) at an excitation wavelength of 800 nm. The value was 1.3 times greater than the maximum value of the σ(2) of MPPBT diss lved in DMSO with ut clay.
Adsorption of Protamine and Papain Proteins on Saponite
Authors: Szabó Tamás , Mitea Raluca , Leeman Hugo , Premachandra Gnanasiri S. , Johnston Cliff T. , Szekeres Márta , Dékány Imre , Schoonheydt Robert A.
Published: November 2008

Due to the increased importance of bionanocomposites, protamine and papain proteins were adsorbed on Na+- and on Cs+-exchanged saponite from aqueous solution. Protein analysis of equilibrium solutions and thermogravimetric analyses of biocomposites were used to prepare adsorption isotherms. Based on the isotherm shape, and on the amounts of protein adsorbed and the amounts of Na+ and Cs+ released, the initial protein sorption apparently was due to ion exchange. Additional sorbed protein was weakly retained and could be removed by washing with water. From ion exchange, the average charge of the protamine adsorbed was estimated to be +13.1 to +13.5. Similar papain measurements could not be made due to partial decomposition. Quantitatively, protamine was adsorbed at levels up to 400 mg/g on Na+-saponite and 200 mg/g on Cs+-saponite. The maximum protamine adsorption was 650 to 700 mg/g for Na+-saponite and 350–400 mg/g for Cs+-saponite. Protamine was sorbed to edge surfaces and the basal spacing of the interlamellar region of saponite was 1.75 nm. Protamine displaced only 36% of the Cs+ in Cs+-saponite and expanded the interlamellar region by 36% for a basal spacing of 1.6 nm. Papain sorption to Na+-saponite occurred by a two-step process: (1) adsorption to saponite particle external surfaces followed, (2) by partial intercalation. Quantitatively, Papain was adsorbed up to 100 mg/g for Na+-and Cs+-saponite. Greater initial papain concentrations resulted in a 450 mg/g maximum for Na+-saponite, but no increase above 100 mg/g for Cs+-saponite. Papain apparently only sorbed to external Cs+-saponite surfaces that were estimated to be 33–40 m2/g. Step-wise thermal decomposition of the saponite-protein composites occurred between 300 and 800°C.