bluuebunny/crossref_metadata_2025 huggingface dataset:
Random subgraph counts andU-statistics: multivariate normal approximation via exchangeable pairs and embedding
Authors: Reinert Gesine , Röllin Adrian
Published: June 2010

In Reinert and Röllin (2009) a new approach - called the ‘embedding method’ - was introduced, which allows us to make use of exchangeable pairs for normal and multivariate normal approximations with Stein's method in cases where the corresponding couplings do not satisfy a certain linearity condition. The key idea is to embed the problem into a higher-dimensional space in such a way that the linearity condition is then satisfied. Here we apply the embedding toU-statistics as well as to subgraph counts in random graphs.
On reliability prediction and semi-renewal processes
Authors: Tortorella Michael
Published: June 2010

We analyze the notion of ‘reliability prediction’ by studying in detail a key property that is tacitly assumed to make reliability prediction possible. The analysis leads in turn to a special type of point process for which the connection of future to past can be explicitly displayed. In this type of process, the semi-renewal process, all finite-dimensional distributions are completely determined by the distribution of the time to the first event in the process. The theory provides a heretofore unappreciated unification of the two most commonly used reliability prediction models for maintained systems, namely, the renewal and revival processes. We show that familiar results from renewal theory extend and generalize to semi-renewal processes.
A new look at transient versions of Little's law, and M/G/1 preemptive last-come-first-served queues
Authors: Fralix Brian H. , Riaño Germán
Published: June 2010

We take a new look at transient, or time-dependent Little laws for queueing systems. Through the use of Palm measures, we show that previous laws (see Bertsimas and Mourtzinou (1997)) can be generalized. Furthermore, within this framework, a new law can be derived as well, which gives higher-moment expressions for very general types of queueing system; in particular, the laws hold for systems that allow customers to overtake one another. What is especially novel about our approach is the use of Palm measures that are induced by nonstationary point processes, as these measures are not commonly found in the queueing literature. This new higher-moment law is then used to provide expressions for all moments of the number of customers in the system in an M/G/1 preemptive last-come-first-served queue at a timet> 0, for any initial condition and any of the more famous preemptive disciplines (i.e. preemptive-resume, and preemptive-repeat with and without resampling) that are analogous to the special cases found in Abate and Whitt (1987c), (1988). These expressions are then used to derive a nice structural form for all of the time-dependent moments of a regulated Brownian motion (see Abate and Whitt (1987a), (1987b)).
Energy efficiency of consecutive fragmentation processes
Authors: Fontbona Joaquín , Krell Nathalie , Martínez Servet
Published: June 2010

Motivated by a problem arising in the mining industry, we present a first study of the energy required to reduce a unit mass fragment by consecutively using several devices. Two devices are considered, which we represent as different stochastic fragmentation processes. Following the self-similar energy model introduced in Bertoin and Martínez (2005), we compute the average energy required to attain a size η0 with this two-device procedure. We then asymptotically compare, as η0 goes to 0 or 1, its energy requirement with that of individual fragmentation processes. In particular, we show that, for a certain range of parameters of the fragmentation processes and of their energy cost functions, the consecutive use of two devices can be asymptotically more efficient than using each of them separately, or vice versa.
Nonhomogeneous random walks systems on ℤ
Authors: Lebensztayn Elcio , Machado Fábio Prates , Zuluaga Martinez Mauricio
Published: June 2010

We consider a random walks system on ℤ in which each active particle performs a nearest-neighbor random walk and activates all inactive particles it encounters. The movement of an active particle stops when it reaches a certain number of jumps without activating any particle. We prove that if the process relies on efficient particles (i.e. those particles with a small probability of jumping to the left) being placed strategically on ℤ, then it might survive, having active particles at any time with positive probability. On the other hand, we may construct a process that dies out eventually almost surely, even if it relies on efficient particles. That is, we discuss what happens if particles are initially placed very far away from each other or if their probability of jumping to the right tends to 1 but not fast enough.
Optimal liquidation of a call spread
Authors: Ekström Erik , Lindberg Carl , Tysk Johan , Wanntorp Henrik
Published: June 2010

We study the optimal liquidation strategy for a call spread in the case when an investor, who does not hedge, believes in a volatility that differs from the implied volatility. The liquidation problem is formulated as an optimal stopping problem, which we solve explicitly. We also provide a sensitivity analysis with respect to the model parameters.
Consenting futures: professional views on social, clinical and ethical aspects of information feedback to embryo donors in human embryonic stem cell research
Authors: Ehrich Kathryn , Williams Clare , Farsides Bobbie
Published: June 2010

This paper reports from an ongoing multidisciplinary, ethnographic study that is exploring the views, values and practices (the ethical frameworks) drawn on by professional staff in assisted conception units and stem cell laboratories in relation to embryo donation for research purposes, particularly human embryonic stem cell (hESC) research, in the UK. We focus here on the connection between possible incidental findings and the circumstances in which embryos are donated for hESC research, and report some of the uncertainties and dilemmas of our staff participants. We explore the views of our study participants in relation to two themes: (1) rights to information and anticipating how donors might be informed about future research findings and (2) occupational work goals and trust.
Autonomy and end-of-life advance directives in Italy: the courts’ struggle against the political majority's attacks on constitutional rights
Authors: Biondi Stefano
Published: June 2010

This paper explores the significance of a landmark Italian judgement regarding end-of-life advance directives, emphasizing the legal and political context in which the decision was made. The analysis particularly focuses on the political majority's attempt to overturn the outcome of the courts’ proceedings - thereby challenging the country's institutional order and jeopardizing constitutional rights.
Patients’ experiences of an intervention to support tuberculosis treatment adherence in South Africa
Authors: Atkins Salla , Biles David , Lewin Simon , Ringsberg Karin , Thorson Anna
Published: June 2010

Objectives:

Tuberculosis (TB) infects over 9 million people annually and, in high prevalence settings, is closely related to HIV/AIDS. Despite this, the two diseases are often treated using contrasting approaches: one focused on patient control, the other focused on empowerment. This article reports on patient experiences of a TB treatment programme in South Africa modelled on the empowerment-oriented antiretroviral treatment (ART) programme.

Methods:

Patients’ perceptions of the programme and its impacts on their lives were investigated through six focus groups with patients from intervention clinics; two focus groups with patients from a comparison clinic; and interviews with two patients who had failed to adhere to the intervention treatment. The data were analysed using content analysis.

Results:

The main themes that emerged were: the tension between agency and coercion in treatment taking; treatment as a lifestyle change; and the role of the lay treatment supporter as either constraining or facilitating empowerment. Patients reported having made lifestyle changes and discussed issues of treatment control and responsibility. However, it seemed that treatment supporters maintained a monitoring role regarding patients’ treatment, limiting patients’ opportunities to exercise control over their illness and their drug regimen.

Conclusions:

The study suggests that differences remain between the ART approach and the new TB treatment model. While the new programme seems to have succeeded in providing additional information, it is not clear that it substantially changed patient agency over their treatment taking in this setting.
Addressing HIV prevention and disease burden among Africans aged over 50 years
Authors: Rammohan Anu , Awofeso Niyi
Published: June 2010

Although sub-Saharan Africans aged 50 years or over constitute about 4.7% of the general population and 5.6% of the total adult population infected with HIV, they remain the forgotten cohort of the AIDS pandemic. Based on a literature review and data from the World Health Organization Demographic Health Surveys, the authors analyse the prevalence of HIV among African men aged 50–59 and provide a brief analysis of risk factors, as well as the influence of demographic, epidemiologic, pathophysiologic and sociocultural transitions on HIV prevention and disease burden among older Africans. Evidence-based HIV prevention and treatment interventions are urgently required in order to address the wellbeing of HIV-infected, older Africans.
Monitoring of Therapy in Congenital Adrenal Hyperplasia
Authors: Dauber Andrew , Kellogg Mark , Majzoub Joseph A
Published: June 2010

BACKGROUND

Congenital adrenal hyperplasia is a group of disorders caused by defects in the adrenal steroidogenic pathways. In its most common form, 21-hydroxylase deficiency, patients develop varying degrees of glucocorticoid and mineralocorticoid deficiency as well as androgen excess. Therapy is guided by monitoring clinical parameters as well as adrenal hormone and metabolite concentrations.

CONTENT

We review the evidence for clinical and biochemical parameters used in monitoring therapy for congenital adrenal hyperplasia. We discuss the utility of 24-h urine collections for pregnanetriol and 17-ketosteroids as well as serum measurements of 17-hydroxyprogesterone, androstenedione, and testosterone. In addition, we examine the added value of daily hormonal profiles obtained from salivary or blood-spot samples and discuss the limitations of the various assays.

Clinical parameters such as growth velocity and bone age remain the gold standard for monitoring the adequacy of therapy in congenital adrenal hyperplasia. The use of 24-h urine collections for pregnanetriol and 17-ketosteroid may offer an integrated view of adrenal hormone production but target concentrations must be better defined. Random serum hormone measurements are of little value and fluctuate with time of day and timing relative to glucocorticoid administration. Assays of daily hormonal profiles from saliva or blood spots offer a more detailed assessment of therapeutic control, although salivary assays have variable quality.
Transgenerational trauma in Gisle Pineau's Chair Piment and Mes Quatre Femmes
Authors: Thomas Bonnie
Published: June 2010

This article explores the notion of transgenerational trauma in Gisle Pineau's 2002 novel Chair Piment and her 2007 autobiographical narrative Mes Quatre Femmes. Initially developed in reaction to the horrors of the Holocaust, transgenerational trauma has since been recognized
as a useful psychological phenomenon with which to study other societies that have experienced deep trauma. In addition to the psychoanalytical insights offered by theorists of memory and trauma, the article will also focus on the Caribbean context of Pineau's work through Edouard Glissant's
theories of memory and Relation. As a practising writer and psychiatric nurse, Pineau's writing responds well to analysis from the dual perspectives of psychology and cultural theory. The books under discussion demonstrate the value of drawing together literature and psychoanalysis and emphasize
the connections between the social and the individual planes. Above all, Pineau underlines the possibility of liberation from transgenerational trauma through openness to others and taking charge of one's own life narrative.
Patrick Chamoiseau's Creole Conteur and the ethics of survival
Authors: Tarica Estelle
Published: June 2010

This article concerns the Creole Conteur in Patrick Chamoiseau's depictions of the slave plantation in Au temps de l'antan (1988a), crire en pays domin (1997) and Texaco (1992). It proposes that Chamoiseau's vision of the plantation be seen as a parable for
contemporary Martinique, one that seeks to reinstate a redemptive history in which the past has a positive claim on the present. The article examines the tensions internal to this recuperative attempt, especially those carried in the relationship between literal and spiritual forms of hunger:
the slaves' famine condition and the survival tactics of dbrouillardise compete with the spiritual nourishment found in an emergent collective identity. The article demonstrates that Chamoiseau uses the Conteur to redraw the symbolic boundaries of the plantation from an amoral
grey zone to a cohesive Creole social order, making the plantation past relevant to the present day. It explores how Chamoiseau preserves the parable's frame of moral instruction even though, as a survival tale involving extreme duress, it involves a calculus beyond good and evil.
Nous sommes tous poursuivis par un monstre: postcolonial hauntologies in the works of Chamoiseau, Ollivier and Haneke
Authors: Campbell Tanya
Published: June 2010

This article seeks to explore the usefulness of Jacques Derrida's notion of hauntology, whereby the past is always revenant and the repressed returns, through analysis of two acclaimed contemporary Caribbean novels by Patrick Chamoiseau and mile Ollivier, and a critically successful
film by Austrian director Michael Haneke. A key theoretical concept, the philosopher's neologism is looked at in a postcolonial frame to explore how painful memory is often repressed or elided to mask historical events, and how the traumas of the past perpetually impinge on the present. This
article contributes to the ever-growing rhetoric around memory in a postcolonial world deeply concerned with issues of remembrance and commemoration. It highlights the important role literature and film have to play in helping us retrieve our forgotten and fragmented past as we continually
seek to make sense of the present.
Cooking with humor: In-group humor as social organization
Authors: Lynch Owen
Published: June 2010

This manuscript provides an understanding of the complex process through which the social organization is (re)produced and transformed through its member's everyday humor. This study is based on a yearlong ethnography of a hotel kitchen that focuses on the in-group humor of chefs as they work. It reveals the chefs' humor as a communicative process that establishes the group's boundaries, the identity of the group members, and the processes through which the group makes sense of and performs its labor. Humor's role within this organizational group is demonstrated through situated episodes that not only (re)produce the status quo, but also provides a strategy for employees to subvert or challenge authoritative power and constraining organizing practices.
Resistance and relief: The wit and woes of early twentieth century folk and country music
Authors: Ellis Iain
Published: June 2010

Folk and country music were rural-based music styles that developed during the pre-rock decades of the early twentieth century. Largely performed by working-class practitioners for working-class audiences, these genres captured the hardships of poor constituencies through markedly different means of humorous expression. Whereas folk employed an often strident satire in resisting perceived oppressors, country looked inwards, using self-deprecating and personalized humor as a shield and relief against outside forces. Narrative tall-tales and regional vernacular were ubiquitous features of folk and country humor, and both crafted struggling characters to serve as illustrative metaphors for broader class concerns. In surveying these music forms in their infancy—as well as their key players—we are connected to the roots of American humor, as well as subsequent developments in rock & roll rebellion.
Cellular Response of Titanium and Its Alloys as Implants
Authors: Bhola Rahul , Bhola Shaily M , Mishra Brajendra , Ayers Reed , Olson David L , Ohno Timothy
Published: June 2010

The cellular response of osteocytes to commercially pure titanium (α) and its alloys (α + β and β) has been tested in a culture media, and the results have been supplemented by analyses from various techniques such as inductively coupled plasma atomic emission spectroscopic (ICP-AES) analysis, X-ray photoemission spectroscopy (XPS), scanning electron microscopy (SEM), metallography, and electrochemical measurements. These results have been correlated with respect to the presence of various alloying elements in these alloys to qualify them for human application. The newer β alloys have been examined for their potential use as implants. These results serve as a preliminary baseline to characterize the best alloy system for a comprehensive long-term investigation.
Effect of Dehiscences to the Bone Response of Implants With an Acid-Etched Surface: An Experimental Study in Miniature Pigs
Authors: Ruehe Baerbel , Heberer Susanne , Bayreuther Katja , Nelson Katja
Published: June 2010

Spontaneous early exposure of submerged implants during the healing phase as a factor for early crestal bone loss around the implants is still being controversially discussed. The aim of this study was to examine the potential impact of dehiscences on the osseointegration process of acid-etched dental implants with a shortened healing period in the maxilla. Five animals received a total of 15 titanium implants 8 weeks postextraction. Eight of these implants were placed in the maxilla to osseointegrate within a shortened healing period of 3 months, whereas the remaining implants were inserted in the lower jaw and served as controls with a regular healing time. Polyfluorochrome sequential labeling with xylenol orange, calcein green, and alizarin complexone was performed 2, 5, and 8 weeks after implant placement. After 12 weeks of unloaded and submerged healing, the animals were killed and the implants removed en bloc. After the processing of the undecalcified PMMA-embedded samples, thin ground sections (40–60 µm) were made. The histomorphometric determination of the bone-to-implant contact (BIC) was calculated using light microscopy. The peri-implant bone apposition rate and the direction of bone growth were determined with the fluorescence microscope. For statistical evaluation, the Mann-Whitney U test, Wilcoxon signed ranks test, and Friedman test were chosen. During the healing period, nonartificial dehiscences were observed at 9 implants. The average BIC was 54.19% (14.51%–68.97%). There were significantly lower BIC rates detected for the cervical part of the implants compared with the middle part. An influence of dehiscences on the osseointegration could not be proven. There were no significant differences between the BIC values of the upper and lower jaw. During the observation period from the third to the eighth week after implantation, the average new bone formation rate was 2.32 µm/d (1.76–2.82 µm/d). During this period, the amount of new bone growth decreased insignificantly. Based on the sequence of the polyfluorochrome labeling, an implantopetal (53.03%) as well as an implantofugal bone growth (46.97%) have been observed. It could be assumed that the acid-etched implants offered a prerequisite to osseointegrate under a shortened healing period. The observed dehiscences seemed not to have compromised the rate of osseointegration.
Everolimus as a new potential antiproliferative agent in aggressive human bronchial carcinoids
Authors: Zatelli Maria Chiara , Minoia Mariella , Martini Chiara , Tagliati Federico , Ambrosio Maria Rosaria , Schiavon Marco , Buratto Mattia , Calabrese Fiorella , Gentilin Erica , Cavallesco Giorgio , Berdondini Lisa , Rea Federico , degli Uberti Ettore C
Published: June 2010

Bronchial carcinoids (BCs) are rare tumors originating from endocrine cells dispersed in the respiratory epithelium. It has been previously demonstrated that everolimus, or RAD001, an mTOR inhibitor, has potent antiproliferative effects in human endocrine tumors. Our aim was to evaluate the possible antiproliferative effects of everolimus in human BCs in primary culture. We collected 24 BCs that were dispersed in primary cultures, treated without or with 1 nM–1 μM everolimus, 10 nM SOM230 (pasireotide, a somatostatin receptor multiligand), and/or 50 nM IGF1. Cell viability was evaluated after 48 h, and chromogranin A (CgA) as well as vascular endothelial growth factor (VEGF) secretion was assessed after 8 h incubation. Somatostatin receptors, mTOR, and AKT expression were investigated by quantitative PCR. We found that in 15 cultures (67.5%), everolimus significantly reduced cell viability (by ∼30%; P<0.05 versus control), inhibited p70S6K activity (−30%), and blocked IGF1 proliferative effects. Everolimus also significantly reduced CgA (by ∼20%) and VEGF (by ∼15%) secretion. Cotreatment with SOM230 did not exert additive effects on cell viability and secretory activity. AKT expression was similar in responder and nonresponder tissues, while mTOR expression was significantly higher in the responder group, which was characterized by higher CgA plasma levels and bigger tumors with higher mitotic index and angiogenesis. Our data demonstrate that everolimus reduces VEGF secretion and cell viability in BCs with a mechanism likely involving IGF1 signaling, suggesting that it might represent a possible medical treatment for BCs.
Uncertainty in urban flood damage assessment due to urban drainage modelling and depth-damage curve estimation
Authors: Freni G. , La Loggia G. , Notaro V.
Published: June 2010

Due to the increased occurrence of flooding events in urban areas, many procedures for flood damage quantification have been defined in recent decades. The lack of large databases in most cases is overcome by combining the output of urban drainage models and damage curves linking flooding to expected damage. The application of advanced hydraulic models as diagnostic, design and decision-making support tools has become a standard practice in hydraulic research and application. Flooding damage functions are usually evaluated by a priori estimation of potential damage (based on the value of exposed goods) or by interpolating real damage data (recorded during historical flooding events). Hydraulic models have undergone continuous advancements, pushed forward by increasing computer capacity. The details of the flooding propagation process on the surface and the details of the interconnections between underground and surface drainage systems have been studied extensively in recent years, resulting in progressively more reliable models. The same level of was advancement has not been reached with regard to damage curves, for which improvements are highly connected to data availability; this remains the main bottleneck in the expected flooding damage estimation. Such functions are usually affected by significant uncertainty intrinsically related to the collected data and to the simplified structure of the adopted functional relationships. The present paper aimed to evaluate this uncertainty by comparing the intrinsic uncertainty connected to the construction of the damage-depth function to the hydraulic model uncertainty. In this way, the paper sought to evaluate the role of hydraulic model detail level in the wider context of flood damage estimation. This paper demonstrated that the use of detailed hydraulic models might not be justified because of the higher computational cost and the significant uncertainty in damage estimation curves. This uncertainty occurs mainly because a large part of the total uncertainty is dependent on depth-damage curves. Improving the estimation of these curves may provide better results in term of uncertainty reduction than the adoption of detailed hydraulic models.
Simulation of sludge dewatering on belt filters
Authors: Christensen Morten Lykkegaard , Petersen Rasmus Rosenlund , Jørgensen Lars Bjerg
Published: June 2010

A mathematical model for belt filters was developed to determine optimum load rate and belt speed during drainage of flocculated biological sludge. Numerical simulations were performed for belt filters with and without plows, and the model fit experimental data well. Experiments showed that highly compressible cakes were formed during drainage, which was important. Due to cake compression, the final sludge dry matter content increased with load rates as long as the drainage time was sufficiently long. The dry matter content could be increased by stacking the cake at the end of the process. An optimum load rate was found. At high load rates, the drainage time was too short and the dry matter content decreased with load due to high cake resistance. The resistance could be lowered by mixing cake and suspension during the process.
A simulation/optimization model for selecting infrastructure alternatives in complex water resource systems
Authors: Arena Claudio , Mazzola Mario Rosario , Scordo Giuseppe
Published: June 2010

The paper introduces a simulation/optimization procedure for the assessment and the selection of infrastructure alternatives in a complex water resources system, i.e. in a multisource (reservoirs) multipurpose bulk water supply scheme. An infrastucture alternative is here a vector X of n decision variables describing the candidate expansions/new plants/water transfers etc. Each parameter may take on a discrete number of values, with its own investment cost attached. The procedure uses genetic algorithms for the search of the optimal vector X through operators mimicking the mechanisms of natural selection. For each X, the value of the objective function (O.F.) is assessed via a simulation model. Simulation is necessary as the O.F. contains, besides investment costs, also incremental operation costs and benefits that depend on the incremental water amounts which the alternative can provide. The simulation model transforms a thirty-year hydrologic input at daily/monthly scale in water allocations, accounting for the usual nonnegativity constraints and using some simple, sytem-specific rules aimed at reducing spills and at sharing water deficits among demand centres. Different O.Fs and constraints have been tested, such as incremental financial cost/benefit minimization under various maximum water deficit constraints scenarios or cost/benefit mimization including scarcity costs. This latter approach has the advantage of implicitly allowing for the magnitude of deficits, but requires the assessment of deficit-scarcity cost relationships. The application of the procedure to a water resources system in south-western Sicily shows that the model is able to converge to results that are consistent with the planning options expressed by the selected O.Fs.
Phosphorus removal from anaerobically digested swine wastewater through struvite precipitation
Authors: Jordaan E. M. , Ackerman J. , Cicek N.
Published: June 2010

Phosphorus removal from agricultural wastewater streams is an important aspect of managing surface water quality, due to the contribution of phosphorus to eutrophication. Removal of phosphorus through struvite precipitation allows for its recovery as a potential fertilizer, and by determining the best conditions for struvite precipitation the removal process can be optimized. The effects of pH, Mg:P ratio, and time on struvite precipitation from anaerobically digested swine manure effluent were investigated. Effluent with Mg:P ratios from 1.0:1 to 1.6:1 were adjusted to pH values between 7.5 and 9.5 and left to equilibrate for 24 h. Results indicate that phosphorus removal increased with increasing pH and Mg:P ratio; the maximum phosphorus removal achieved was 80% at pH 9.0 and a Mg:P ratio of 1.6:1. The purest struvite precipitate was found at pH 7.5, with calcium carbonate and struvite precipitating at higher pH values. A continuously stirred batch of centrate was adjusted to pH 8.4 to determine the struvite formation rate constant. The rate constant was found to be 1.55 h−1, with 17% phosphorus removal during the first 20 min. The results indicate that struvite precipitation could be a viable method of phosphorus removal from anaerobically digested swine manure.
Degradation of a mixture of pollutants in water using the UV/H2O2 process
Authors: Mariani M. L. , Labas M. D. , Brandi R. J. , Cassano A. E. , Zalazar C. S.
Published: June 2010

The degradation reaction of a simple mixture of pollutants (dichloroacetic acid + formic acid) employing H2O2 and UVC radiation (253.7 nm) has been studied in a well-mixed reactor which operates inside a recycling system. The aim of this work is to develop a systematic methodology for treating degradation of mixtures of pollutants, starting from a rather manageable system to more complex aggregates. In this contribution, the effects of different variables such as hydrogen peroxide/pollutant mixture initial concentration ratio, pH and incident radiation at the reactor wall were studied. The results show that the best degrading conditions are: pH = 3.5 and hydrogen peroxide concentrations from 3.9 to 11.8 mM (134–400 mg/L), for initial concentrations of 1.10 and 0.39 mM for formic acid and dichoroacetic acid respectively (50 mg/L for both pollutants). The influence of the incident radiation at the reactor wall on the degradation rates of the mixture is significant. In addition to this, it has been shown that in the employed aqueous solution no stable reaction intermediates are formed. On this basis, a complete reaction scheme for the mixture is proposed that is suitable for a reaction kinetics mathematical modeling of the mixture and further studies of increasing complexity.
The heterogeneous photo-Fenton reaction using goethite as catalyst
Authors: Ortiz de la Plata Guadalupe B. , Alfano Orlando M. , Cassano Alberto E.
Published: June 2010

In the present work the degradation of 2-chlorophenol (2-CP) used as model compound, applying the Heterogeneous photo-Fenton reaction, was studied. Small particles of goethite or iron oxyhydroxide were used as a source of iron. The influence of catalyst loading, radiation intensity and the molar ratio between hydrogen peroxide and contaminant were examined. Improvement by illumination is highly significant. During the progress of 2-CP degradation, the reaction shows an unusual acceleration. This autocatalytic comportment, with stronger tendencies at higher temperatures, implies a completely different behaviour from the one typically expected. The autocatalytic performance is successfully explained by the joint action of two factors: (i) the evolution of the available iron in the homogeneous phase during the course of the reaction and (ii) the autocatalytic contribution of some of the reaction intermediates in the iron cycle. The small iron concentration leaching into the solution is produced by two typical liquid medium – solid goethite surface dissolution processes. A reaction mechanism has been proposed and, in a first stage, parameters have been obtained for the dark reaction. In a second step, the complete data for the irradiated operation were obtained.
Spatial and temporal variability of fecal indicator bacteria in an urban stream under different meteorological regimes
Authors: Cha Sung Min , Lee Seung Won , Park Yong Eun , Cho Kyung Hwa , Lee Seungyoon , Kim Joon Ha
Published: June 2010

As a representative urban stream in Korea, the Gwangju (GJ) stream suffers from chronic fecal contamination. In this study, to characterize levels of fecal pollution in the GJ stream, the monthly monitoring data for seven years (from 2001 to 2007) and the hourly monitoring data from two field experiments were examined with respect to seasonal/daily variations and spatial distribution under wet and dry weather conditions. This research revealed that concentrations of fecal indicator bacteria strongly varied depending on the prevalent meteorological conditions. That is, during the dry daytime, fecal indicator bacteria concentrations decreased due to inactivation from solar irradiation, but rapidly increased in the absence of sunlight, suggesting external source inputs. In addition, bacterial concentrations substantially increased during rainfall events, due probably to a major contribution from combined sewer overflow. The observations in this study can be useful for implementing fecal pollution management strategies and for predicting fecal contamination as a function of meteorological conditions.
Transition of water demand and treatment plant overcapacity: a case study of the Seoul Metropolitan City, Korea
Authors: Lee Sangeun , Park Heekyung
Published: June 2010

This study deals with the overcapacity problem of water treatment plants in Korea, and mainly discusses status, causes, and engineering options. To this end, we first statistically analyze the recent trend of demand, revealing that the demands of small- and mid-size systems are still increasing while that of large-size systems is now decreasing. Since the existing approach to plan capacity implicitly assumes that demand will increase at a regular rate, we estimate excess capacities and system utilizations of large-size systems. From these results it is found that the large-size systems are suffering from serious overcapacity, thus necessitating that engineers make very difficult decisions given that systems are still expanding the capacities of plants due to a lack of awareness of the current demand trend. For other systems where there is a better understanding of the transition of demand, planners have ceased to expand plants or have closed down relatively old plants in efforts to reduce O&M costs. To address this problem, quick recognition of the transition of demand is being highlighted by the concepts of integrated resources management and cybernetics. Therefore, we examined how quickly the new trend of the Seoul case could be precisely recognized and appropriately addressed. Using the Bayesian parameter estimation method, we found that a new trend can be recognized six years after the transition of demand.
Sonochemical degradation of ofloxacin in aqueous solutions
Authors: Hapeshi E. , Achilleos A. , Papaioannou A. , Valanidou L. , Xekoukoulotakis N. P. , Mantzavinos D. , Fatta-Kassinos D.
Published: June 2010

The use of low frequency (20 kHz), high energy ultrasound for the degradation of the antibiotic ofloxacin in water was investigated. Experiments were performed with a horn-type ultrasound generator at varying applied power densities (130–640 W/L), drug concentrations (5–20 mg/L), hydrogen peroxide concentrations (0–100 mM) and sparging gases (air, oxygen, nitrogen and argon). In general, conversion (which was assessed following sample absorbance at 288 nm) increased with increasing ultrasound energy and peroxide concentration and decreasing initial drug concentration. Moreover, reactions under an argon atmosphere were faster than with diatomic gases, possibly due to argon's physical properties (e.g. solubility, thermal conductivity and specific heat ratio) favoring sonochemical activity. Overall, low to moderate levels of ofloxacin degradation were achieved (i.e. it never exceeded 50%), thus indicating that radical reactions in the liquid bulk rather than thermal reactions in the vicinity of the cavitation bubble are responsible for ofloxacin degradation.
Activated sludge behaviour in a batch reactor in the presence of antibiotics: study of extracellular polymeric substances
Authors: Avella A. C. , Essendoubi M. , Louvet J. N. , Görner T. , Sockalingum G. D. , Pons M. N. , Manfait M. , de Donato Ph.
Published: June 2010

The influence of Erythromycin,Roxithromycin,Amoxicillin, Tetracycline and Sulfamethoxazole on municipal sludge in batch reactors was investigated. The study was focused on extracellular polymeric substances (EPS) as indicator of bacteria sensitivity to toxic agents. The EPS were analysed by UV-Vis and FT-IR spectroscopies and by size exclusion chromatography. It was found that Erythromycin and Roxithromycin induced a significant increase of bound EPS in flocs. This was attributed to a protection mechanism of the bacteria. Erythromycin was the only antibiotic which inhibited COD and nitrogen removal.
Theory and Evidence on Governance: Conceptual and Empirical Strategies of Research on Governance in Education
Authors: Altrichter Herbert
Published: June 2010

During the last 20 years many European education systems have seen profound changes in the way they are governed. This also applies to the school systems of German-speaking countries which until then had been characterized by a long period of stability. Both political rhetoric and actual changes have rightly attracted increased attention of educational researchers, resulting in a growing body of work on the ‘governance’ of schooling. There is no such word as ‘governance’ in the German language. Nevertheless, a type of studies called ‘Governance Studies’, ‘Governance Research’ or ‘Governance Perspective’ has recently evolved in German-speaking social sciences. This article aims to make accessible this strand of research which has not yet been extensively published in languages other than German. Further, it intends to explore its links and relationships to other European research approaches. First, the article explains in what way the concept of ‘governance’ has been defined in German educational research. The second section discusses some of its methodological aspirations. In the third part, some examples of empirical research on changing educational governances are discussed in order to give an idea of how this research approach currently unfolds.
Student Participation in Activities with Influential Outcomes: Issues of Gender, Individuality and Collective Thinking in Swedish Secondary Schools
Authors: Rönnlund Maria
Published: June 2010

Drawing on a study in three Swedish lower secondary schools, this article examines how students engaged in the democratic processes involved in the formation of an action group intended to influence their school by making it more environmentally friendly. The aim is to acquire greater understanding of influential processes in relation to gender and both individualistically and collectively oriented ideas, including understanding of which students participate in such groups, the role gender plays in the likelihood of a student participating, how they act, and their experiences of participation. From observations of, and interviews with, four participants, girls were found both to be more active participants and to have more positive experiences than boys. It is concluded that the group represents an arena for both individual and collective performance in which both individual and collective ideas are reflected. However, differences in the expectations of boys and girls, concerning where and how they feel they should act and perform in school, seems to make the arena more suitable and more effective for girls than boys. While the girls' participation provided them with political confidence, the two participating boys did not gain this from the experience.
Time, Space and Young People's Agency in Vocational Upper Secondary Education: A Cross-Cultural Perspective
Authors: Hjelmér Carina , Lappalainen PA , Rosvall Per-Åke
Published: June 2010

This article is based on ethnographic studies in the context of vocational education: two in Sweden and one in Finland. The Swedish data originate from the Vehicle programme and the Child and Recreation programme; the Finnish data originate from the social and health-care sector. In this sense, the authors' perspective is cross-cultural. The article focuses on temporal and spatial dimensions of these three educational contexts and analyzes how young people exhibit their agency when negotiating their time and constructing their own space. The authors' analysis elucidates how time—space paths in the context of vocational education are classed and gendered. In the female-dominated fields of vocational upper secondary education, disciplinary practices related to time and space are more visible than in the male-dominated fields. Moreover, it is argued that the political atmosphere in Sweden has been more favourable for promoting equality than that in Finland. Despite this, divisions between students and pigeonholing exist in everyday school life.
On limit distribution of the Hurwitz zeta-function
Authors: Laurinčikas Antanas
Published: June 2010

The distribution of the vector (|ζ(s, α)|; ζ(s, α)), where ζ(s, α) is the Hurwitz zeta-function with transcendental parameter α, is considered and a probabilistic limit theorem is obtained. Also, the dependence between |ζ(s, α)| and ζ(s, α) in terms of m-characteristic transforms is discussed.
The Economic Effect of Education in an Information Technology–Penetrating Economy
Authors: Chan Chi Wai
Published: June 2010

This article examines the economic effect of education in terms of its impact on the earnings of workers in an information technology (IT)–diffusing economy, based on data from Hong Kong’s 2006 by-census and survey on the usage and penetration of IT in industries. Education enhances the productivity of workers and increases their lifetime incomes. However, technological advances, if deskilling, may exert an adverse effect on workers’ earnings. The analysis of the economic effect of education is complicated by the increasing application of technologies in the workplace. This study shows that the earnings effect of education and the interaction between education and IT penetration in the workplace are positive and significant, whereas IT by itself brings about a significant negative earnings effect.
A Review of the “Digital Turn” in the New Literacy Studies
Authors: Mills Kathy Ann
Published: June 2010

Digital communication has transformed literacy practices and assumed great importance in the functioning of workplace, recreational, and community contexts. This article reviews a decade of empirical work of the New Literacy Studies, identifying the shift toward research of digital literacy applications. The article engages with the central theoretical, methodological, and pragmatic challenges in the tradition of New Literacy Studies, while highlighting the distinctive trends in the digital strand. It identifies common patterns across new literacy practices through cross-comparisons of ethnographic research in digital media environments. It examines ways in which this research is taking into account power and pedagogy in normative contexts of literacy learning using the new media. Recommendations are given to strengthen the links between New Literacy Studies research and literacy curriculum, assessment, and accountability in the 21st century.
A Systematic Review and Meta-Analysis of the Cognitive Correlates of Bilingualism
Authors: Adesope Olusola O. , Lavin Tracy , Thompson Terri , Ungerleider Charles
Published: June 2010

A number of studies have documented the cognitive outcomes associated with bilingualism. To gain a clear understanding of the extent and diversity of these cognitive outcomes, the authors conducted a meta-analysis of studies that examined the cognitive correlates of bilingualism. Data from 63 studies (involving 6,022 participants) were extracted and analyzed following established protocols and procedures for conducting systematic reviews and guidelines for meta-analysis. Results indicate that bilingualism is reliably associated with several cognitive outcomes, including increased attentional control, working memory, metalinguistic awareness, and abstract and symbolic representation skills. Overall mean effect sizes varied from small to large, depending on the cognitive outcomes measured, and were moderated by methodological features of the studies.
Spatial Trends of Genetic Variation of Domestic Ruminants in Europe
Authors: Laloë Denis , Moazami-Goudarzi Katayoun , Lenstra Johannes A. , Marsan Paolo Ajmone , Azor Pedro , Baumung Roswitha , Bradley Daniel G. , Bruford Michael W. , Cañón Javier , Dolf Gaudenz , Dunner Susana , Erhardt Georg , Hewitt Godfrey , Kantanen Juha , Obexer-Ruff Gabriela , Olsaker Ingrid , Rodellar Clemen , Valentini Alessio , Wiener Pamela , ECGDCEC
Published: June 2010

The introduction of livestock species in Europe has been followed by various genetic events, which created a complex spatial pattern of genetic differentiation. Spatial principal component (sPCA) analysis and spatial metric multidimensional scaling (sMDS) incorporate geography in multivariate analysis. This method was applied to three microsatellite data sets for 45 goat breeds, 46 sheep breeds, and 101 cattle breeds from Europe, Southwest Asia, and India. The first two sPCA coordinates for goat and cattle, and the first sPCA coordinate of sheep, correspond to the coordinates of ordinary PCA analysis. However, higher sPCA coordinates suggest, for all three species, additional spatial structuring. The goat is the most geographically structured species, followed by cattle. For all three species, the main genetic cline is from southeast to northwest, but other geographic patterns depend on the species. We propose sPCA and sMDS to be useful tools for describing the correlation of genetic variation with geography.
Lead Generation and Optimization Based on Protein-Ligand Complementarity
Authors: Ogata Koji , Isomura Tetsu , Kawata Shinji , Yamashita Hiroshi , Kubodera Hideo , Wodak Shoshana J.
Published: June 2010

This work proposes a computational procedure for structure-based lead generation and optimization, which relies on the complementarity of the protein-ligand interactions. This procedure takes as input the known structure of a protein-ligand complex. Retaining the positions of the ligand heavy atoms in the protein binding site it designs structurally similar compounds considering all possible combinations of atomic species (N, C, O, CH3, NH,etc). Compounds are ranked based on a score which incorporates energetic contributions evaluated using molecular mechanics force fields. This procedure was used to design new inhibitor molecules for three serine/threonine protein kinases (p38 MAP kinase, p42 MAP kinase (ERK2), and c-Jun N-terminal kinase 3 (JNK3)). For each enzyme, the calculations produce a set of potential inhibitors whose scores are in agreement with IC50 data and Ki values. Furthermore, the native ligands for each protein target, scored within the five top-ranking compounds predicted by our method, one of the top-ranking compounds predicted to inhibit JNK3 was synthesized and his inhibitory activity confirmed against ATP hydrolysis. Our computational procedure is therefore deemed to be a useful tool for generating chemically diverse molecules active against known target proteins.
A Compact Tunable Diode Laser Absorption Spectrometer to Monitor CO2 at 2.7 µm Wavelength in Hypersonic Flows
Authors: Vallon Raphäel , Soutadé Jacques , Vérant Jean-Luc , Meyers Jason , Paris Sébastien , Mohamed Ajmal
Published: June 2010

Since the beginning of the Mars planet exploration, the characterization of carbon dioxide hypersonic flows to simulate a spaceship’s Mars atmosphere entry conditions has been an important issue. We have developed a Tunable Diode Laser Absorption Spectrometer with a new room-temperature operating antimony-based distributed feedback laser (DFB) diode laser to characterize the velocity, the temperature and the density of such flows. This instrument has been tested during two measurement campaigns in a free piston tunnel cold hypersonic facility and in a high enthalpy arc jet wind tunnel. These tests also demonstrate the feasibility of mid-infrared fiber optics coupling of the spectrometer to a wind tunnel for integrated or local flow characterization with an optical probe placed in the flow.