bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends in organic carbon and nitrogen contents in agricultural soils in Bavaria (south Germany) between 1986 and 2007
Authors: Capriel P.
Published: July 2013

In the last 60 years traditional agriculture in industrialized European countries, which had initially been dependent on available natural resources, has shifted towards a massive intensification of nutrient turnover because of cheap energy and low‐cost synthetic fertilizers. At the same time farm structure has undergone profound changes, resulting in an increase in the number of specialized farms to the detriment of traditional non‐specialized ones. All these trends have had a significant impact on agricultural management. The intensification of agricultural management together with climate change could affect the quantity and quality of soil organic matter (SOM). That could imply decreasing soil fertility, reduced harvest yields, increasing nutrient losses and additional greenhouse gas emission. In order to measure the long‐term development of SOM in agricultural soils a monitoring programme was initiated in Bavaria in 1986. The measurements are based on 92 representative plots located on cropland and 21 plots located on managed permanent grassland. Between 1986 and 2007 the monitoring plots have been sampled four times. The monitoring results suggest a decrease of soil organic carbon content, total nitrogen content and C:N ratio in cropland as well as in grassland in Bavaria between 1986 and 2007. Crops and organic fertilizers are together with the initial SOM content the main causes of the observed changes in SOM quantity and quality. A climatic effect could be neither proved nor excluded. The results in Bavaria are consistent with the reported changes in organic carbon of agricultural soils in Austria, Belgium, France, the Netherlands and England. In Bavaria we should expect declining SOM stocks, particularly soil organic carbon, in agricultural soils if the supply of organic matter remains constant or even decreases.
Neutral endopeptidase regulates neurogenic inflammatory responses induced by stimulation of human oral keratinocytes with bacterial lipopolysaccharide and nicotine
Authors: Nakata Motoki , Awano Shuji , Kinoshita Naomasa , Yoshida Akihiro , Ansai Toshihiro
Published: July 2013

Neutral endopeptidase (NEP) is present on various epithelial cells and inactivates numerous physiologically active peptides. Neutral endopeptidase may regulate proinflammatory signals in oral mucosal epithelium. However, the function of NEP in oral mucosal epithelium is unknown. The present study investigated the action of NEP upon proinflammatory signals on human oral keratinocytes and the influence of endothelin‐converting enzyme (ECE)‐1, an enzyme similar to NEP, on the functions of NEP. Oral keratinocytes were cultured in medium containing inflammatory inducers [lipopolysaccharide (LPS) and nicotine], NEP inhibitors, and ECE‐1/NEP inhibitors, either alone or in combination. The concentrations of substance P (SP) and interleukin‐1β (IL‐1β) were measured in the supernatant. Additionally, the concentrations of SP and IL‐1β were measured in the supernatant of cells incubated with LPS or nicotine after transfection with NEP small interfering RNA (siRNA). The concentrations of SP and IL‐1β were significantly increased in cells incubated with NEP inhibitors and, to a lesser extent, in cells incubated with ECE‐1/NEP inhibitors, compared with controls (cells incubated with LPS or nicotine alone). The concentrations of SP and IL‐1β in cells transfected with NEP siRNA were significantly augmented compared with controls. In conclusion, the present study demonstrated that NEP down‐regulated the levels of SP and IL‐1β produced from human oral keratinocytes, although ECE‐1 may be partly related to the down‐regulation.
Projected climate impacts to South African maize and wheat production in 2055: a comparison of empirical and mechanistic modeling approaches
Authors: Estes Lyndon D. , Beukes Hein , Bradley Bethany A. , Debats Stephanie R. , Oppenheimer Michael , Ruane Alex C. , Schulze Roland , Tadross Mark
Published: July 2013

Crop model‐specific biases are a key uncertainty affecting our understanding of climate change impacts to agriculture. There is increasing research focus on intermodel variation, but comparisons between mechanistic (MMs) and empirical models (EMs) are rare despite both being used widely in this field. We combined MMs and EMs to project future (2055) changes in the potential distribution (suitability) and productivity of maize and spring wheat in South Africa under 18 downscaled climate scenarios (9 models run under 2 emissions scenarios). EMs projected larger yield losses or smaller gains than MMs. The EMs’ median‐projected maize and wheat yield changes were −3.6% and 6.2%, respectively, compared to 6.5% and 15.2% for the MM. The EM projected a 10% reduction in the potential maize growing area, where the MM projected a 9% gain. Both models showed increases in the potential spring wheat production region (EM = 48%, MM = 20%), but these results were more equivocal because both models (particularly the EM) substantially overestimated the extent of current suitability. The substantial water‐use efficiency gains simulated by the MMs under elevated CO2 accounted for much of the EM−MM difference, but EMs may have more accurately represented crop temperature sensitivities. Our results align with earlier studies showing that EMs may show larger climate change losses than MMs. Crop forecasting efforts should expand to include EM−MM comparisons to provide a fuller picture of crop–climate response uncertainties.
The integrated management for renal replacement therapy in Portugal
Authors: Coelho Anabela P. , Sá Helena O. , Diniz José A. , Dussault Gilles
Published: July 2013

Portugal was the first European country to introduce an integrated management of end‐stage renal disease (IM ESRD). This new program integrates various dialysis services and products, which are reimbursed at a fixed rate/patient/week called “comprehensive price payment.” This initiative restructured the delivery of dialysis services, the monitoring of outcomes, and the funding of renal replacement therapy. This article described the implementation of a new model of comprehensive provision of hemodialysis (HD) services and aimed to assess its impact on dialysis care. Quality assessments and reports of patient satisfaction, produced by the Ministry of Health since 2008, as well as national registries and reports, provided the data for this review. Indicators of HD services in all continental facilities show positive results that have successively improved along the period of 2009–2011, in spite of an average annual growth of 3% of the population under HD treatment. Mortality rates for HD patients were 12.7%, 12%, and 11%, respectively in 2009, 2010, and 2011; annual hospitalization rates were 4.9%, 3.8%, and 4.4% for the same years; key performance indicators showed averages above the reference values such as hemoglobin, serum phosphorus, eKt/V, water quality, number of days of hospitalization per patient per year, and number of weekly dialysis sessions. The financing analysis of IM ESRD demonstrates a sustained control of global costs, without compromising quality. The IM ERSD program is an innovative and quality‐driven approach that benefits both dialysis patients and providers, contributing toward the rationalization of service provision and the efficient use of resources.
Interactive effects of obligate scavengers and scavenger community richness on lagomorph carcass consumption patterns
Authors: Sebastián‐González Esther , Sánchez‐Zapata José Antonio , Donázar José Antonio , Selva Nuria , Cortés‐Avizanda Ainara , Hiraldo Fernando , Blázquez Miguel , Botella Francisco , Moleón Marcos
Published: July 2013

Carrion consumption patterns in vertebrate scavenger communities may be influenced by several interacting factors. We assessed the effects of the number of scavenger species and the presence of obligate scavengers (vultures) on carcass detection and consumption times, and the structure (nestedness) of the scavenger assemblage by exploring consumption patterns of lagomorph carcasses provided experimentally. Carcass detection and consumption times were strongly inversely related to vulture presence, whereas scavenger richness had a low contribution, except when interacting with vulture presence. However, none of the scavenger communities presented a nested pattern, perhaps because of the small size of lagomorphs, which prevents large numbers of scavengers and interspecific interactions occurring at one carcass. Our results suggest that scavenger species richness, especially the presence of vultures, increases scavenging efficiency.
Providing chicks with extra food lowers male but not female provisioning in the House Sparrow Passer domesticus
Authors: Cleasby Ian R. , Nakagawa Shinichi , Burke Terry
Published: July 2013

We assessed whether adult House Sparrows Passer domesticus adjusted their provisioning in response to an experimental increase in the nutritional condition of their nestlings. When we supplemented chicks directly with additional food, male parents, but not female parents, reduced their provisioning. The results for males, but not females, run contrary to a previous experiment in this species. In addition, female provisioning was positively associated with both brood size and the age of the brood. In contrast, whereas male provisioning was positively associated with brood size, males did not increase provisioning as their chicks grew older. Males, but not females, exhibited repeatability in their provisioning. Food supplementation had a larger positive effect upon nestling survival in smaller broods than in larger broods. Overall, there appear to be fundamental differences between males and females in how decisions regarding the level of parental investment in the current brood are made.
ON THE PROBLEM OF PREVENTION
Authors: BENOÎT JEAN‐PIERRE , DUBRA JUAN
Published: July 2013

Disasters are often precipitated by insufficient preventive care. We argue that there is a problem of prevention in that this lack of care often stems from agents’ rational calculations. Positive experiences lead agents to underestimate the risks of disasters; technological improvements and redundancies designed for safety induce agents to reduce their care. Although lower care increases the chances of an accident, the number of redundancies can be adjusted to offset this. However, the accident probability remains constant even as ostensible improvements in safety are made. Checklists can be used to decrease the number of accidents.
INCOME REDISTRIBUTION AND PUBLIC GOOD PROVISION: AN EXPERIMENT
Authors: MAURICE JONATHAN , ROUAIX AGATHE , WILLINGER MARC
Published: July 2013

We experimentally investigate the impact of income redistribution on voluntary contributions by groups of four subjects. We compare equalizing and unequalizing redistribution. Our data are consistent with the neutrality theorem: Redistribution does not affect the amount of voluntarily provided public good at the group level. However, at the individual level, subjects tend to underadjust with respect to the Nash prediction. We also observe an insignificant adjustment asymmetry between the poor and the rich: Subjects who become poorer adjust their contribution by a larger absolute amount than subjects who become richer. Finally, poor subjects tend to overcontribute significantly more than rich subjects.
MEASURING ECONOMIC INSECURITY
Authors: BOSSERT WALTER , D'AMBROSIO CONCHITA
Published: July 2013

We provide an axiomatic treatment of the measurement of economic insecurity, assuming that individual insecurity depends on the current wealth level and its variations experienced in the past. The first component plays the role of a buffer stock to rely on in case of an adverse future event. The second component determines the confidence an individual has on her ability to overcome a loss in the future. Two classes of linear measures are characterized with sets of plausible and intuitive axioms and, for each of these classes, an important subclass is identified.
ENVIRONMENTAL MANAGEMENT POLICY UNDER INTERNATIONAL CARBON LEAKAGE
Authors: KIYONO KAZUHARU , ISHIKAWA JOTA
Published: July 2013

This article studies environmental management policy when two fossil‐fuel‐consuming countries noncooperatively regulate greenhouse‐gas emissions through emission taxes or quotas. The presence of carbon leakage caused by fuel‐price changes affects the tax‐quota equivalence. We explore each country's incentive to choose a policy instrument in a two‐stage policy choice game and find subgame‐perfect Nash equilibria. This sheds new light on the questions of which policy instrument is more stringent and of why adopted instruments could be different among countries. In particular, our result suggests a reason why developing countries tend to employ emission taxes whereas developed countries tend to adopt quotas.
Effects on the Quality of the Nursing Care Process Through an Educational Program and the Use of Electronic Nursing Documentation
Authors: Bruylands Michelle , Paans Wolter , Hediger Hannele , Müller‐Staub Maria
Published: July 2013

Purpose

To evaluate the effect of the educational program “Guided Clinical Reasoning” (GCR) and the introduction of an intelligent electronic nursing documentation system (e‐doc) on the quality of the nursing process.

Methods

Evaluation was conducted at three measurement points and rated with the instrument “Quality of Nursing Diagnoses, Interventions and Outcomes” (Q‐DIO).

Findings

GCR showed the best Q‐DIO‐scores. No long‐term effect was found after GCR cessation. The e‐doc delivered the lowest scores, while showing adequate support in using nursing diagnoses.

Conclusions

E‐docs can support conducting the nursing process, but for meaningful e‐doc use, clinical reasoning is essential.

Implications

High‐quality nursing documentation requires recognition of factors obstructing or supporting nurses in the use of e‐docs while conducting the nursing process.
Parental effects on the larval performance of a tapeworm in its copepod first host
Authors: Benesh D. P.
Published: July 2013

Parents can influence the phenotype of their offspring through various mechanisms, besides the direct effect of heredity. Such parental effects are little explored in parasitic organisms, perhaps because in many parasites, per capita investment into offspring is low. I investigated whether parental identity, beyond direct genetic effects, could explain variation in the performance of the tapewormSchistocephalus solidusin its first intermediate host, a copepod. I first determined that two breeding worms could be separated from one another after ~48 h ofin vitroincubation and that the isolated worms continued producing outcrossed eggs, that is, rates self‐fertilization did not increase after separation. Thus, from a breeding pair, two sets of genetically comparable eggs can be collected that have unambiguous parental identities. In an infection experiment, I found that the development of larval worms tended to vary between the two parental worms within breeding pairs, but infection success and growth rate in copepods did not. Accounting for this parental effect decreased the estimated heritability for development by nearly half. These results suggest that larval performance is not simply a function of a worm's genotype; who mothered or fathered an offspring can also affect offspring fitness, contradicting the perhaps naïve idea that parasites simply produce large quantities of uniformly low‐quality offspring.
Prevalence gradients of Friedreich's Ataxia and R1b haplotype in Europe co‐localize, suggesting a common Palaeolithic origin in the Franco‐Cantabrian ice age refuge
Authors: Vankan Pierre
Published: July 2013

Combining data from epidemiological studies in Friedreich's Ataxia (FRDA) and patient organization membership lists, shows that FRDA prevalence exhibits large regional differences in Europe with a prevalence gradient from west to east. Highest levels are observed in northern Spain, south of France and Ireland, lowest levels in Scandinavia and Russia. The observed distribution of FRDA in Europe co‐localizes with the gradient of the chromosomal R1b marker as detected within west Europe. This gradient is either derived from Palaeolithic migrations out of the Franco‐Cantabrian Ice age refuge or from Neolithic migrations entering west Europe with the advance of agriculture. FRDA prevalence may have been increased in this population anytime after its separation from the closely related R1a carrying group. East European populations with a high frequency of the R1a marker show 10 fold lower prevalence of FRDA, indicating that the FRDA mutation was present in the common ancestor and was increased in the R1b carrying group. The FRDA carrying population went through a Palaeolithic population bottleneck supporting the view that the observed FRDA distribution and potentially the R1b distribution are derived from Palaeolithic migrations out of the Franco‐Cantabrian ice age refuge.
Diabetes in Friedreich Ataxia
Authors: Cnop Miriam , Mulder Hindrik , Igoillo‐Esteve Mariana
Published: July 2013

Diabetes is a common metabolic disorder in patients with Friedreich ataxia. In this Supplement article, we review the clinical data on diabetes in Friedreich ataxia, and the experimental data from rodent and in vitro models of the disease. Increased body adiposity and insulin resistance are frequently present in Friedreich ataxia, but pancreatic β cell dysfunction and death are a conditio sine qua non for the loss of glucose tolerance and development of diabetes. The loss of frataxin function in mitochondria accounts for these pathogenic processes in Friedreich ataxia. Mitochondria are essential for the sensing of nutrients by the β cell and for the generation of signals that trigger and amplify insulin secretion, known as stimulus‐secretion coupling. Moreover, in the intrinsic pathway of apoptosis, pro‐apoptotic signals converge on mitochondria, resulting in mitochondrial Bax translocation, membrane permeabilization, cytochrome c release and caspase cleavage. How and at which level frataxin deficiency impacts on these processes in β cells is only partially understood. A better understanding of the molecular mechanisms mediating β cell demise in Friedreich ataxia will pave the way for new therapeutic approaches.
Nikolaus Friedreich and degenerative atrophy of the dorsal columns of the spinal cord
Authors: Koeppen Arnulf H.
Published: July 2013

Nikolaus Friedreich (1825–1882) presented clinical findings in six patients with a severe hereditary disorder of the nervous system and secured full autopsies in four of them. He was fascinated by the spinal cord lesions in the siblings of two unrelated families, and in the first three of his five long articles stressed the destruction of the dorsal columns. He recognized the relatively minor symmetrical lesions of the anterolateral fasciculi but did not separate dorsal spinocerebellar tracts (Flechsig's bundles) and corticospinal tracts. Although he studied the dorsal spinal roots in great detail and established their principal abnormality, namely, axonal thinning without axonal loss, he reported dorsal root ganglia as entirely normal. He made an insightful description of atrophic neurons in the gracile nuclei (clavae) but overlooked the invariable atrophy of the dentate nuclei. He followed the families over a period of 14 years, but acknowledged the hereditary nature of the disease only very late. He proposed a developmental defect for the medulla oblongata, retaining his interpretation that the spinal lesion was inflammatory. This review honors Friedreich for his insight into a ‘new’ disease in the late 19th century and updates his neuropathological findings. It is remarkable that Friedreich also described the abnormal hearts in the disease that now bears his name since hypertrophic cardiomyopathy is now recognized as the main cause of death in Friedreich's ataxia.
Frataxin: a protein in search for a function
Authors: Pastore Annalisa , Puccio Helene
Published: July 2013

Reduced levels of the protein frataxin cause the neurodegenerative disease Friedreich's ataxia. Pathology is associated with disruption of iron–sulfur cluster biosynthesis, mitochondrial iron overload, and oxidative stress. Frataxin is a highly conserved iron‐binding protein present in most organisms. Despite the intense interest generated since the determination of its pathology, identification of the cellular function of frataxin has so far remained elusive. In this review, we revisit the most significant milestones that have led us to our current understanding of frataxin and its functions. The picture that emerges is that frataxin is a crucial element of one of the most essential cellular machines specialized in iron‐sulfur cluster biogenesis. Future developments, therefore, can be expected from further advancements in our comprehension of this machine.
Mitochondrial pathophysiology in Friedreich's ataxia
Authors: González‐Cabo Pilar , Palau Francesc
Published: July 2013

Neurological examination indicates that Friedreich's ataxia corresponds to a mixed sensory and cerebellar ataxia, which affects the proprioceptive pathways. Neuropathology and pathophysiology of Friedreich's ataxia involves the peripheral sensory nerves, dorsal root ganglia, posterior columns, the spinocerebellar, and corticospinal tracts of the spinal cord, gracile and cuneate nuclei, dorsal nuclei of Clarke, and the dentate nucleus. Involvement of the myocardium and pancreatic islets of Langerhans indicates that it is also a systemic disease. The pathophysiology of the disease is the consequence of frataxin deficiency in the mitochondria and cells. Some of the biological consequences are currently recognized such as the effects on iron–sulfur cluster biogenesis or the oxidative status, but others deserve to be studied in depth. Among physiological aspects of mitochondria that have been associated with neurodegeneration and may be interesting to investigate in Friedreich's ataxia we can include mitochondrial dynamics and movement, communication with other organelles especially the endoplasmic reticulum, calcium homeostasis, apoptosis, and mitochondrial biogenesis and quality control. Changes in the mitochondrial physiology and transport in peripheral and central axons and mitochondrial metabolic functions such as bioenergetics and energy delivery in the synapses are also relevant functions to be considered. Thus, to understand the general pathophysiology of the disease and fundamental pathogenic mechanisms such as dying‐back axonopathy, and determine molecular, cellular and tissue therapeutic targets, we need to discover the effect of frataxin depletion on mitochondrial properties and on specific cell susceptibility in the nervous system and other affected organs.
Clinical features of Friedreich's ataxia: classical and atypical phenotypes
Authors: Parkinson Michael H. , Boesch Sylvia , Nachbauer Wolfgang , Mariotti Caterina , Giunti Paola
Published: July 2013

One hundred and fifty years since Nikolaus Friedreich's first description of the degenerative ataxic syndrome which bears his name, his description remains at the core of the classical clinical phenotype of gait and limb ataxia, poor balance and coordination, leg weakness, sensory loss, areflexia, impaired walking, dysarthria, dysphagia, eye movement abnormalities, scoliosis, foot deformities, cardiomyopathy and diabetes. Onset is typically around puberty with slow progression and shortened life‐span often related to cardiac complications. Inheritance is autosomal recessive with the vast majority of cases showing an unstable intronic GAA expansion in both alleles of the frataxin gene on chromosome 9q13. A small number of cases are caused by a compound heterozygous expansion with a point mutation or deletion. Understanding of the underlying molecular biology has enabled identification of atypical phenotypes with late onset, or atypical features such as retained reflexes. Late‐onset cases tend to have slower progression and are associated with smaller GAA expansions. Early‐onset cases tend to have more rapid progression and a higher frequency of non‐neurological features such as diabetes, cardiomyopathy, scoliosis and pes cavus. Compound heterozygotes, including those with large deletions, often have atypical features. In this paper, we review the classical and atypical clinical phenotypes of Friedreich's ataxia.
Nephroprotective effects of Isaria felina in rats with adenine-induced chronic renal failure
Authors: Yang Xihua , Zhang Shengwan , Ren Liansheng , Zhang Hong , Bai Xihua
Published: July 2013

Objective

Chronic renal failure (CRF) is a progressive, life-threatening condition with limited treatment options. Cordyceps sinensis is a fungus that has nephroprotective effects, and Isaria felina (IF) is a fungus isolated from C. sinensis fruiting bodies. We evaluated IF efficacy using an adenine-induced CRF animal model.

Methods

Forty male Sprague-Dawley rats were divided into normal control (n = 8) and adenine groups (n = 32; 100 mg/kg for 30 days). The adenine group was subdivided into a model control group (n = 7), a positive control group (200 mg/kg Jinshuibao capsule (JSB; n = 8), and two IF groups (200 mg/kg, n = 8; 100 mg/kg, n = 8). After treatment for 30 days, animals were narcotized and abdominal aortic blood was analysed. Kidney functions were evaluated.

Key findings

Higher serum creatinine, blood urea nitrogen and uric acid levels, and lower creatinine clearance was observed in the model control group compared with JSB and IF groups (P < 0.05). Red blood cell count, haemoglobin and haematocrit levels in the 200 mg/kg IF group were higher than in the model control group (P < 0.05). Transforming growth factor-β1 mRNA expression in the model control group was higher than the normal control and 200 mg/kg IF groups (P < 0.05). Epidermal growth factor mRNA in the model control group was lower than in the normal control and both IF-treated groups (P < 0.05). Structural renal damage was observed in all adenine-treated rats, but was less severe in the JSB and IF groups.

Conclusion

IF may reverse the damaged kidney functions-induced with adenine in rats.
In vivo organization of the FtsZ‐ring by ZapA and ZapB revealed by quantitative super‐resolution microscopy
Authors: Buss Jackson , Coltharp Carla , Huang Tao , Pohlmeyer Chris , Wang Shih‐Chin , Hatem Christine , Xiao Jie
Published: July 2013

In most bacterial cells, cell division is dependent on the polymerization of the FtsZ protein to form a ring‐like structure (Z‐ring) at the midcell. Despite its essential role, the molecular architecture of the Z‐ring remains elusive. In this work we examine the roles of two FtsZ‐associated proteins, ZapA and ZapB, in the assembly dynamics and structure of the Z‐ring in Escherichia coli cells. In cells deleted of zapA or zapB, we observed abnormal septa and highly dynamic FtsZ structures. While details of these FtsZ structures are difficult to discern under conventional fluorescence microscopy, single‐molecule‐based super‐resolution imaging method Photoactivated Localization Microscopy (PALM) reveals that these FtsZ structures arise from disordered arrangements of FtsZ clusters. Quantitative analysis finds these clusters are larger and comprise more molecules than a single FtsZ protofilament, and likely represent a distinct polymeric species that is inherent to the assembly pathway of the Z‐ring. Furthermore, we find these clusters are not due to the loss of ZapB–MatP interaction in ΔzapA and ΔzapB cells. Our results suggest that the main function of ZapA and ZapB in vivo may not be to promote the association of individual protofilaments but to align FtsZ clusters that consist of multiple FtsZ protofilaments.
Educational outcome in adolescence following pyloric stenosis repair before 3 months of age: a nationwide cohort study
Authors: Hansen Tom G. , Pedersen Jacob K. , Henneberg Steen W. , Morton Neil S. , Christensen Kaare
Published: July 2013

Background

Immature animals exposed to anesthetics display apoptotic neurodegeneration with subsequent long‐term cognitive dysfunctions. Young age at anesthetic exposure is believed to be critical, but human studies are scarce. This study investigated the association between exposure to surgery and anesthesia for pyloric stenosis (PS) before 3 months of age and subsequent educational outcome in adolescence.

Methods

This nationwide unselected register‐based follow‐up study of the Danish birth cohorts 1986–1990 compared the educational outcome of all children having undergone surgery for PS before 3 months of age with a randomly selected, age‐matched 5% sample of the same cohort. Primary analysis compared the average test scores at ninth grade adjusting for gender, birth weight, and parental age and education. Secondary analysis compared the proportions not attaining the test scores between the two groups.

Results

The exposure group comprised 779 and the control group consisted of 14 665 individuals. Although the exposure group performed lower than the control group (average score 0.17 lower, 95% CI: 0.08–0.25), after adjusting for known confounders, no statistically significant difference (−0.04, 95% CI: −0.09 to 0.08) between the 2 groups could be demonstrated. However, we found an odds ratio (OR) for test score nonattainment‐associated PS repair of 1.37 (95% CI: 1.11–1.68).

Conclusion

Children operated for PS before 3 months of age have educational performance tests similar to the background population at age 15–16 years after adjusting for known confounders. The higher nonattainment rate could suggest that a subgroup of PS children is developmentally disadvantaged.
Der Wert der Reisezeit deutscher Pendler
Authors: Obermeyer Andy , Evangelinos Christos , Besherz Andreas
Published: July 2013

Travel time savings are usually the most important utility component of transport projects. This paper shows estimation of the value of travel time savings (VTTS) with particular focus on random parameter models. Employing these models commuters’ VTTS in the German City Dresden is estimated. Results show that travel time savings of motorised and non-motorised modes are valued differently, VTTS derived in this study are higher than values currently used in Germany’s federal transport infrastructure plan and VTTS are dependent on travel time.
Supply Chain Integration, Product Modularity, and Market Valuation: Evidence from the Solar Energy Industry
Authors: Davies Jane , Joglekar Nitin
Published: July 2013

Supply chain integration is increasingly seen as a method to obtain flexibility and, consequently, to provide competitive advantage for firms within a supply chain. Product modularity, either in concert with or independent of such integration, can also produce flexibility for firms within a supply chain. In this proof‐of‐concept research, we explore whether the supply chain network affects each constituent firm's market valuation and how decisions regarding the level of supply chain integration and the usage of product modularity are associated with the value of the supply chain. We develop a method to identify and measure the supply chain's effect on each constituent firm's market valuation. Results indicate that greater integration is associated with a higher supply chain valuation, whereas increasing aggregated product modularity across the supply chain relates to a lower supply chain value. However, when combined, the interaction of aggregated product modularity and supply chain integration is positively associated with the supply chain's valuation.
Is the Provincial Capital Market Segmented in China?
Authors: Chan Kenneth , Lai Jennifer , Yan Isabel
Published: July 2013

This paper evaluates the degree of provincial capital mobility in China since 1978 by estimating the saving‐retention rate in the Feldstein and Horioka framework. It is found that the estimate of the saving retention rate tends to be biased downward if we fail to decompose the investment and saving rates into the private and government components. After the decomposition, we find that the private capital mobility was low prior to the 1990s, but improved notably in the more recent period. We also find that the saving‐retention rate for the government sector remains negative throughout the sample, which can partially be explained by the government's reallocation of capital from the more productive regions to the less productive regions. Comparing the results of China with those of Japan shows that Japan had a much higher degree of prefectural capital mobility than China before the 1990s, but the gap gradually closed up afterwards.
Rabies Prevention and Management of Cats in the Context of Trap–Neuter–Vaccinate–Release Programmes
Authors: Roebling A. D. , Johnson D. , Blanton J. D. , Levin M. , Slate D. , Fenwick G. , Rupprecht C. E.
Published: July 2013

Domestic cats are an important part of many Americans' lives, but effective control of the 60–100 million feral cats living throughout the country remains problematic. Although trap–neuter–vaccinate–return (TNVR) programmes are growing in popularity as alternatives to euthanizing feral cats, their ability to adequately address disease threats and population growth within managed cat colonies is dubious. Rabies transmission via feral cats is a particular concern as demonstrated by the significant proportion of rabies post‐exposure prophylaxis associated with exposures involving cats. Moreover, TNVR has not been shown to reliably reduce feral cat colony populations because of low implementation rates, inconsistent maintenance and immigration of unsterilized cats into colonies. For these reasons, TNVR programmes are not effective methods for reducing public health concerns or for controlling feral cat populations. Instead, responsible pet ownership, universal rabies vaccination of pets and removal of strays remain integral components to control rabies and other diseases.
Suppression of Regenerative Chatter in a Plunge-Grinding Process by Spindle Speed
Authors: Yan Yao , Xu Jian
Published: July 2013

This paper utilizes an effective control strategy to suppress the regenerative chatter in a plunge-grinding process. To begin with, the dynamical interaction between the workpiece and the grinding wheel is considered as a major factor influencing the grinding stability. Mathematically, the grinding stability is studied through numerical eigenvalue analysis. Consequently, critical chatter boundaries are obtained to distinguish the chatter-free and the chatter regions. As known, the grinding is unstable and the chatter happens in the chatter region. To observe the chatter vibrations, an analytical method and numerical simulations are employed. As a result, chatter vibrations both with and without losing contact between the workpiece and the wheel are obtained. Meanwhile, the coexistence of the chatter and the stable grinding is also found in the chatter-free region. Finally, a control strategy involving spindle speed variation (SSV) is introduced to suppress the chatter. Then, its effectiveness is analytically investigated in terms of the method of multiple scales (MMS).
Chemical Mechanical Polishing Slurries for Chemically Vapor-Deposited Diamond Films
Authors: Yuan Zewei , Jin Zhuji , Zhang Youjun , Wen Quan
Published: July 2013

The objective of this study is to investigate slurries for chemical mechanical polishing (CMP) of chemically vapor-deposited (CVD) diamond films based on the principle of thermokinetics combined with physical and chemical properties. The study uses the mechanical work, surface energy and oxidability of a slurry with diamond carbon as the main physical-chemical indicators in selecting the slurries. The study indentifies 10 CMP slurries of different oxidants, such as potassium ferrate, potassium permanganate, chromium trioxide and potassium dichromate, for CVD diamond film polishing. Prior to a CMP process, prepolishing with a boron carbide plate is performed to prepare a CVD diamond film with acceptable surface finish and flatness. After polishing with the CMP process a CVD diamond film is examined with optical microscopy, surface profilometry, atomic force microscopy and X-ray photoelectron spectroscopy for information on surface finish and quality, material removal and mechanisms. The study demonstrates that among the ten CMP slurries, the one with potassium ferrate as an oxidant provides the highest material removal rate of 0.055 mg/hour, and the best surface finish (Ra = 0.187 nm) and surface quality (no surface scratches nor pits), which is followed by potassium permanganate. It then discusses how mechanical stress may promote the chemical oxidation of an oxidant with diamond by forming “C-O” and “C=O” on diamond surface. The study concludes that chemical mechanical polishing is effective for CVD diamond films.
M–K Analysis of Forming Limit Diagram Under Stretch-Bending
Authors: He Ji , Cedric Xia Z. , Li Shuhui , Zeng Danielle
Published: July 2013

Since the forming limit diagram (FLD) was introduced by Keeler, etc., five decades ago, it has been intensively studied by researchers and engineers. Most work has focused on the in-plane deformation which is considered as the dominant mode of the majority forming processes. However the effect of out-of-plane deformation becomes important in the accurate prediction of formability when thick sheet metals and/or smaller forming radii are encountered. Recent research on the stretch-bending induced FLD (BFLD) has been inconclusive. Some studies indicated that the bending effect will enhance a sheet metal's formability while others suggested otherwise. In this paper, we present an in-depth study of the through-thickness bending effect on the forming limits. The Marciniak–Kuczynski (M–K) analysis is extended to include bending, and models based on both flow theory and deformation theory of plasticity are proposed. The study is limited to the right-hand-side of FLD where the bending is along the major stretch direction. The radial return method is adopted as the framework to integrate constitutive equations. The results show that the bending process decreases the sheet metal formability with the flow-theory based model, while the opposite is true if the deformation theory based analysis is adopted. A detailed examination of the deformation histories from those two models reveals that the loading–unloading-reverse loading process during stretch-bending holds the key to the understanding of the conflicting results. The insight gained from the proposed FLD prediction model in this paper provides a new understanding of how the bending process affects the FLD, which can be used to predict and explain the localized necking phenomenon under the stretch-bending condition.
Design of Threaded Fatigue Test Specimen for Machining
Authors: Akyildiz Hamza K. , Livatyali Haydar
Published: July 2013

Design and machining of the fatigue test specimens have significant effects on the duration and reliability of fatigue test. Fatigue test specimens essentially consist of three parts: the center or critical test section, which is the region where required conditions are simulated as closely as possible, and the two ends, which serve to transfer the load from the grips to the center section. When high strength materials are used for a complex geometry, such as a thread need to be tested, design and manufacturing of the specimens become more influential on the reliability and duration of the tests. Threaded fatigue test specimens were designed, machined, and tested in a four-point rotary bending fatigue testing machine. An innovative threaded fatigue test specimen that consistently fails at the critical test section was designed, machined, and tested successfully to give the required fatigue notch factor. Because of full scale fatigue testing with threaded parts is very expensive and sometimes dangerous, evaluated threaded fatigue specimen can be used in fatigue testing and it reduces duration of the experiment more than 60% for machined threaded specimens.
Performance Modeling of a Modern Gas Turbine for Dispatch Optimization
Authors: Boksteen S. Z. , van der Vecht D. J. , Pecnik R. , van Buijtenen J. P.
Published: July 2013

As electricity demand from individual power plants is expected to fluctuate increasingly due to the growing share of renewables, operators of large Combined Cycle Gas Turbine power plants will have to deal with increasing load variations and rapid load changes. To keep up reliability and availability of the plants, it is useful to accurately keep track of plant performance by comparing actual cycle data with a steady state base case model. This paper presents various aspects of the performance modeling of Alstom’s GT26 gas turbine as recently installed in the Netherlands. The modeling environment is GSP, a component based zero-dimensional software tool. Firstly, the modeling strategy is presented, taking into account the specific features of this sequential combustion gas turbine. Secondly, the method of processing field measurements to model inputs is shown and furthermore, the influence of measurement uncertainty on model parameter estimation is assessed. Procedures will be proposed to use this model in daily operation, to keep track of actual component loading. Later on, the recorded performance data can be used to evaluate maintenance as a function of actual operational history, as a basis for future strategies.
Considerations on the Numerical Modelling and Performance of Axial Swirlers Under Relight Conditions
Authors: Koupper Charlie , Grech Nicholas , Zachos Pavlos K. , Pachidis Vassilios , Singh Riti
Published: July 2013

Numerical modelling of aero engine combustors under relight conditions is a matter of continuously increasing importance due to the demanding engine certification regulations. In order to reduce the complexity and the cost of the numerical modelling, common practice is to replace the atomizer’s swirlers with velocity profiles boundary conditions, very often scaled down from nominal operating conditions assuming similarity of the swirler flowfield. The current numerical study focuses on the flowfield characteristics of an axially swirled atomizer operating within a windmilling engine environment. The scalability of the velocity profile from higher power settings is examined. Observations on the performance of the axial swirler under relight conditions are also made.

Experimental data was used as a validation platform for the numerical solver, after a grid sensitivity study and a turbulence model selection process. Boundary conditions for simulating the windmilling environment were extracted from experimental work.

The swirler axial and tangential velocity profiles were normalised using the swirler inlet velocity. Results showed that both profiles are only scalable for windmilling conditions of high flight Mach number (≥ 0.5). At low flight Mach numbers, the actual profile had a lower velocity than that predicted through scaling. The swirl number was found to deteriorate significantly with the flight velocity following a linear trend, reducing significantly the expected flame quality. As a consequence the burner is forced to operate at the edge of its stability loop with low certainty regarding its successful relight.
Wind Energy Resource Assessment and Power Production Estimates as an Undergraduate Project
Authors: Nix Andrew C. , Lawson Seth A. , Murphy Robert G.
Published: July 2013

It is common practice to install wind-monitoring stations in geographical locations having high winds to estimate power production prior to installing large-scale wind farms. For the current study, a wind-monitoring program was developed as an educational tool for undergraduate engineering students at West Virginia University. The focus of this paper is not on the results of the assessment, but rather on how this program was used as a hands-on approach for educating students about wind energy and availability. The objective of the student/industry collaborative project was to determine the feasibility of constructing a wind farm to power a federal prison facility located in an area with an abundant wind resource in North Central West Virginia, while educating students on wind energy.

This paper presents a description and assessment of this program as an undergraduate senior design project. As part of the program, students played a key role from the developmental stages of the project, to the assessment of the results. During the first semester of the senior design project, students procured a wind monitoring station based on down-select criteria, selected the site for construction, installed the wind monitoring station, commissioned the sensor suite, and performed quality assurance/quality control (QA/QC) of and evaluated the initial data sets. Students logged data through the second semester of the program, performed data quality monitoring, processed average wind speed and direction data into frequency distributions and wind roses, analyzed monthly and diurnal averages in wind resources and performed power production calculations. Several different methodologies were employed, including application of fluid control volume energy analysis to derive Betz’ limit, turbine efficiency curves with operational limits and Weibull statistics to employ online power production estimators. The program successfully introduced students to the applicability of their engineering education to the area of renewable energy.
Sirocco Fan Design for Residential Ventilation Through Multi-Objective Optimization to Enhance Aerodynamic Performance
Authors: Kim Jin-Hyuk , Cha Kyung-Hun , Kim Kwang-Yong
Published: July 2013

A multi-objective optimization of a sirocco fan for residential ventilation has been carried out in the present work. A hybrid multi-objective evolutionary algorithm combined with response surface approximation is applied to optimize the total-to-total efficiency and total pressure rise of the sirocco fan for residential ventilation. Three-dimensional Reynolds-averaged Navier-Stokes equations with the shear stress transport turbulence model are discretized by finite volume method and solved on hexahedral grids for the flow analysis. Numerical results are validated with the experimental data for the total-to-total efficiency and total pressure. The total-to-total efficiency and total pressure rise of the sirocco fan are used as objective functions for the optimization. In order to improve the total-to-total efficiency and total pressure rise of the sirocco fan, four variables defining the scroll cut-off angle, scroll diffuser expansion angle, hub ratio and the blade exit angle, respectively, are selected as the design variables in this study. Latin-hypercube sampling as design-of-experiments is used to generate the design points within the design space. A fast non-dominated sorting genetic algorithm with an ε–constraint strategy for the local search is applied to determine the global Pareto-optimal solutions. The trade-off between two objectives is determined and discussed with respect to the representative clustered optimal solutions in the Pareto-optimal solutions compared to the reference shape.