bluuebunny/crossref_metadata_2025 huggingface dataset:
On Constraining Pilot Point Calibration with Regularization in PEST
Authors: Fienen Michael N. , Muffels Christopher T. , Hunt Randall J.
Published: April 2009

Ground water model calibration has made great advances in recent years with practical tools such as PEST being instrumental for making the latest techniques available to practitioners. As models and calibration tools get more sophisticated, however, the power of these tools can be misapplied, resulting in poor parameter estimates and/or nonoptimally calibrated models that do not suit their intended purpose. Here, we focus on an increasingly common technique for calibrating highly parameterized numerical models—pilot point parameterization with Tikhonov regularization. Pilot points are a popular method for spatially parameterizing complex hydrogeologic systems; however, additional flexibility offered by pilot points can become problematic if not constrained by Tikhonov regularization. The objective of this work is to explain and illustrate the specific roles played by control variables in the PEST software for Tikhonov regularization applied to pilot points. A recent study encountered difficulties implementing this approach, but through examination of that analysis, insight into underlying sources of potential misapplication can be gained and some guidelines for overcoming them developed.
Lady Astor's Campaign for Nursery Schools in Britain, 1930–1939: Attempting to Valorize Cultural Capital in a Male-Dominated Political Field
Authors: Brehony Kevin J.
Published: April 2009

This article examines the work of Lady Nancy Astor (1879–1964) in campaigning for nursery education and nursery schools in Britain from the late 1920s until the Second World War. Arguably no elected politician in England at any time, including the present, has identified themselves more closely with the cause of nursery schooling in Britain. Historiography that focuses on the impact of exceptional “pioneers” is frequently hagiographical and emphasizes the actions of charismatic figures at the expense of contexts and the hidden political, economic, and social forces operating within them. The main assumption underlying the approach here is that individuals are themselves shaped by social relations and that their capacity to impact on events depends on the structure of social relations and their place within them. This formulation, although derived mainly from debates within Marxist theory, shares affinities with the work of Pierre Bourdieu, who saw society as constituted by fields in which agents endowed with varying amounts of economic, cultural, and symbolic capital compete for scarce material and symbolic goods in “a general economy of practices.”
Poverty and Parenting: Transforming Early Education's Legacy in the 1960s
Authors: Rose Elizabeth
Published: April 2009

Head Start, the federal program that provides preschool education, health, and social services for children from poor families, is one of the United States' most popular government programs. Created in 1965, it has endured as a symbol of commitment to children, serving just fewer than one million children a year in neighborhood sites across the country. Most accounts of Head Start's history do not start much before 1964 when Sargent Shriver, charged with directing Lyndon Johnson's antipoverty campaign, decided to focus funds on young children. Neither Shriver nor most of those he consulted in planning the new program were particularly conscious of earlier efforts to combat poverty by educating young children. Nevertheless, the program they designed carried forward important aspects of turn-of-the-twentieth-century free kindergartens and day nurseries, as well as the nursery schools sponsored by the federal government in the 1930s.
The United States and the World: A History of Connections in Early Childhood Education
Authors: Hinitz Blythe E.
Published: April 2009

As examples from this issue show, early education practice around the world has long been intertwined and the care and education provided for young children in most places draws at least in part from non-indigenous sources. A review of the articles reveals numerous parallels and even direct linkages between U.S. early childhood advocates and educators and each of the countries highlighted. Similarities are to be found, for example, in their patterns of development and in the impediments faced by the advocates and founders of day nurseries, kindergartens, and nursery schools in each country. Collaboration between early childhood educators in the United States and their counterparts around the world, beginning in the 1800s with ocean voyages and postal mail, has grown today with the use of modern technology and the continuation of consultative visits by U.S. experts to many lands.
A Critical Analysis of Ecosystem Services as a Tool in Conservation Projects
Authors: Goldman Rebecca L. , Tallis Heather
Published: April 2009

Human modifications of the environment are growing in number and geographic extent, expanding to all of the Earth's surfaces and affecting the vast majority of the Earth's natural resources. Increases in demand for resources, growing levels of poverty, and more extensive urbanization, among other changes, lead to a need to move beyond parks and classic conservation approaches to incorporate humans and working landscapes more directly in conservation efforts. One approach to do this is to focus on ecosystem services, the benefits ecosystems provide to humans. Here conservation projects that focus only on biodiversity are analytically compared with those that include ecosystem‐service goals to dispel myths and explore promises. Projects conducted by The Nature Conservancy, the world's largest conservation organization, are used, and it is demonstrated that not only do ecosystem‐service approaches engage new landscapes, stakeholders, and funding sources, but that they do so without neglecting traditional biodiversity goals and the traditional approaches of protection and preservation. Seven case studies that uniquely create a broker‐type structure to determine how to distribute money for the provision of particular services to the satisfaction of a wide range of stakeholder interests are focused on. It is found that all use local, independent leadership to initiate partnership formation, which then leads to the creation of a separate institutional entity that has legal rights to determine fund provision. The activities encouraged by these entities, and which therefore appear to satisfy a wide array of interests, are supporting education, rewarding best management practice, creating jobs, and monitoring outcomes.
Economic Impacts of Invasive Species in Forests
Authors: Holmes Thomas P. , Aukema Juliann E. , Von Holle Betsy , Liebhold Andrew , Sills Erin
Published: April 2009

Biological invasions by nonnative species are a by‐product of economic activities, with the vast majority of nonnative species introduced by trade and transport of products and people. Although most introduced species are relatively innocuous, a few species ultimately cause irreversible economic and ecological impacts, such as the chestnut blight that functionally eradicated the American chestnut across eastern North America. Assessments of the economic costs and losses induced by nonnative forest pests are required for policy development and need to adequately account for all of the economic impacts induced by rare, highly damaging pests. To date, countrywide economic evaluations of forest‐invasive species have proceeded by multiplying a unit value (price) by a physical quantity (volume of forest products damaged) to arrive at aggregate estimates of economic impacts. This approach is inadequate for policy development because (1) it ignores the dynamic impacts of biological invasions on the evolution of prices, quantities, and market behavior, and (2) it fails to account for the loss in the economic value of nonmarket ecosystem services, such as landscape aesthetics, outdoor recreation, and the knowledge that healthy forest ecosystems exist. A review of the literature leads one to anticipate that the greatest economic impacts of invasive species in forests are due to the loss of nonmarket values. We proposed that new methods for evaluating aggregate economic damages from forest‐invasive species need to be developed that quantify market and nonmarket impacts at microscales that are then extended using spatially explicit models to provide aggregate estimates of impacts. Finally, policies that shift the burden of economic impacts from taxpayers and forest landowners onto parties responsible for introducing or spreading invasives, whether through the imposition of tariffs on products suspected of imposing unacceptable risks on native forest ecosystems or by requiring standards on the processing of trade products before they cross international boundaries, may be most effective at reducing their impacts.
Ecosystem Responses to Community Disassembly
Authors: Zavaleta Erika , Pasari Jae , Moore Jonathan , Hernández Daniel , Suttle K. Blake , Wilmers Christopher C.
Published: April 2009

Ecosystems around the world are experiencing unprecedented rates of extinction and species decline. The question of how community disassembly—the ongoing process of nonrandom species losses and declines—affects ecosystem functions, including those that influence persistence of other species, is addressed. The order in which species disappear from a community depends on their vulnerability to specific stressors and on traits associated with inherent susceptibility to decline. Information on species characteristics associated with vulnerability (response traits) is synthesized, and it is asked whether they are associated with characteristics that underpin significant contributions to ecosystem functioning (effect traits). Direct evidence that community disassembly affects ecosystem functioning comes from a variety of sources, ranging from documentation of long‐term changes following the loss of an initial species or fragmentation of a landscape, to modeling and manipulative experiments that simulate species losses and observe their consequences. The usefulness to conservation and restoration practice of community disassembly as a concept is evaluated, and it is asked whether and how community disassembly can provide guidance about species loss order, its consequences, what each of these depends on, and whether a positive link exists between vulnerability and contribution to function—a link that would exacerbate the consequences of the ongoing extinction crisis.
Behavioral Indicators for Conserving Mammal Diversity
Authors: Morris Douglas W. , Kotler Burt P. , Brown Joel S. , Sundararaj Vijayan , Ale Som B.
Published: April 2009

Mammals are threatened with population decline and extinction. Numerous species require immediate conservation intervention. But our ability to identify species on the brink of decline, and to intervene successfully, depends on developing reliable leading indicators of population, community, and environmental change. Classic approaches, such as population and life history assessment, as well as indicator species, trail environmental change. Adaptive behaviors honed by natural selection to respond quickly to environmental changes represent true leading indicators that we can learn to apply to conservation and management. Excellent examples of useful behaviors for conservation include foraging behavior, patch use, and habitat selection. Comparisons among giving‐up densities collected in artificial resource patches can effectively indicate the forager's predation costs, its habitat quality, mechanisms of coexistence, and environmental richness. Patterns of adaptive habitat use can similarly reveal the relative value of different types of habitat, the location, and amounts of source versus sink habitat in a landscape, the effects of human disturbance, and projections on future extinction risk. Each behavior is likely to change more quickly than population size. As useful as these and related indicators may be to managers and conservationists, similar behaviors can emerge from different causes, and immediate returns of behavior to fitness may cause rapid evolution of associated morphological and physiological traits. Conservation strategies will thereby often be most effective if they build on research programs targeting the processes influencing adaptive behaviors and that assess whether wild‐type or novel behaviors are most likely to sustain populations into the future.
Dermatoses caused by infestations of immature Ixodes spp. on dogs and cats in Sydney, Australia
Authors: Baxter CG , Vogelnest LJ , Doggett SL
Published: April 2009

Infestations of larval and nymphal Ixodes spp. were identified in 16 dogs and 16 cats from several small animal clinics in Sydney. Cases occurred in late summer or autumn, peaking in February, and were seasonally recurrent in some individuals. Clinical signs of infestation included a papular dermatitis and irritation or pruritus that ranged from severe to mild or absent. The distribution of tick attachment tended to be cranial and ventral, with the face, legs, axillae and ventrum the most commonly affected sites. The estimated number of ticks in each infestation varied from less than 10 to more than 100. Basic morphological examination of ticks collected from affected animals was performed by attending veterinarians using light microscopy, and larvae and nymphs belonging to the Ixodes genus were identified. Ticks collected from 17 animals and submitted to the Department of Medical Entomology, Westmead Hospital were putatively identified as I. trichosuri (57%) and I. holocyclus (25%) larvae. Histopathological samples of attachment sites collected from three dogs and one cat were characterised by ticks attached in well‐demarcated invaginations of the skin (‘tick craters’) associated with variable epidermal and/or dermal necrosis, focal eosinophilic intraspinous pustules, mild to marked eosinophilic and neutrophilic, superficial to deep, dermal perivascular to interstitial inflammation, and moderate to marked superficial dermal oedema and red cell extravasation. A range of topical acaricidal preparations, including fipronil and synthetic pyrethroids, were used for treatment.
Inherited diseases of Australian Holstein‐Friesian cattle
Authors: Windsor PA , Agerholm JS
Published: April 2009

Inherited disorders are of major importance in Holstein‐Friesian cattle, a breed that now dominates the global dairy industry. Recent developments in the breed reflect intensive selection programs for production traits, identifying elite sires whose genotypes are rapidly spread worldwide through the use of breeding programs involving advanced reproductive technologies. These elite sires carry mutations responsible for disease. Consequently, the mating of descendants of an elite sire (as with any sire) substantially increases the risk of producing defective progeny. The important inherited disorder citrullinaemia was disseminated globally in the 1970s and first reported in Australian Holstein‐Friesians. However, a range of inherited disorders more recently recognised internationally in this breed have remained unreported in Australia, although recent genotyping studies suggest they have probably occurred. A survey of these disorders suggests a decline in surveillance for such diseases in Australia. Clinical and pathological descriptions are presented to enable practitioners and producers to recognise and report these disorders, and a proposal is advanced to establish a health program to manage this issue.
Are the Australian poultry industries vulnerable to large outbreaks of highly pathogenic avian influenza?
Authors: Hamilton SA , East IJ , Toribio J‐A , Garner MG
Published: April 2009

Objective  To describe the structure of the Australian poultry industry and discuss the potential for highly pathogenic avian influenza (HPAI) to spread between Australian poultry farms.

Procedure  High densities of poultry farms, frequent contacts between farms by service providers, the supply of live poultry markets (LPM) and the presence of free‐range duck flocks in affected regions have been identified as risk factors for the spread of HPAI between flocks in outbreaks causing the death or destruction of over 1 million poultry overseas. Data on 1,594 commercial Australian chicken meat, chicken egg, duck and turkey farms were collected by a telephone questionnaire of farm managers to assess the risk of a HPAI outbreak in Australia.

Results and Discussion  Five regions of Australia had farm densities comparable to overseas regions that experienced widespread HPAI. Common service providers routinely contacted different classes and types of farms over wide geographic areas. However, no responding farms supplied LPM and the majority of duck farms did not produce free‐range ducks.

Conclusion  Outbreaks of HPAI have the potential to cause serious impacts on the Australian poultry industry. The risk posted by LPM and free‐range ducks is limited, but the movement of genetic stock and common service providers could spread infection between companies, industries or geographical regions. Biosecurity measures are therefore considered critical to limit the secondary spread of infection should an outbreak occur.
Double‐outlet right ventricle in a 10‐month‐old Friesian filly
Authors: Fennell LC , Church S , Tyrell D , Forbes G , Charles JA , McCowan C , Savage CJ
Published: April 2009

A 10‐month‐old Friesian filly had a presentation that was consistent with chronic left‐ and right‐sided congestive heart failure. Clinical pathology findings included abnormal haematological and biochemical variables, abnormal blood gas values and increased serum concentration of cardiac troponin I. Echocardiography revealed cardiac chamber dilation and dextropositioning of the aorta. Radiography revealed a generally enlarged heart and pulmonary interstitial infiltration. These findings were supported at necropsy and the diagnosis of double‐outlet right ventricle was confirmed. The pathological changes and physiological responses subsequent to double‐outlet right ventricle have not previously been described in detail in horses. Clinical progression closely resembles that seen in humans, in whom antemortem diagnosis relies on echocardiography. In horses, complex cardiac disease presents a diagnostic challenge to the clinician. Appropriate therapy must be based on an accurate diagnosis.
IN THIS ISSUE – May 2009
Authors: Jackson A
Published: April 2009

Australian poultry industries and highly pathogenic avian influenza ▪ Diagnosis of canine splenic disorders ▪ Dermatoses caused by immature Ixodes spp. ▪ Seizures during medetomidine sedation and local anaesthesia ▪ Inherited diseases of Holstein‐Friesian cattle ▪ Oral and topical triclabendazole ▪ Double‐outlet right ventricle in a filly
A Case–Sibling Assessment of the Association Between Skin Pigmentation and Other Vitamin D‐related Factors and Type 1 Diabetes Mellitus
Authors: Ponsonby Anne‐Louise , Cameron Fergus , Saffery Richard , Pezic Angela , Wong Nick , Craig Jeff , Ellis Justine , Dwyer Terence
Published: April 2009

Fair skin pigmentation has been associated with a higher risk of type 1 diabetes mellitus (T1DM). The aim is to compare children with T1DM directly to a sibling in relation to their skin pigmentation in sun‐exposed and unexposed sites, past sun exposure and methylation of the VDR gene promoter. The sample consisted of children with T1DM attending a diabetes outpatient clinic and siblings (total n = 42). Cutaneous melanin density was estimated using a spectrophotometer. Parental report on past sun exposure was obtained. DNA methylation analysis of the VDR gene promoter was conducted. Matched data analysis was performed comparing each case directly to their sibling. Cases were significantly more likely to have lighter skin pigmentation at the upper arm (AOR 0.69 [95% CI: 0.52, 0.90]; P = 0.01). Low infant sun exposure was imprecisely associated with a two‐fold increase in T1DM risk (AOR 2.43 [95% CI: 0.91, 6.51]; P = 0.08 for under 1 h of winter sun exposure per leisure day). The VDR gene promoter was completely unmethylated in both cases and siblings. The previously demonstrated association between light skin pigmentation and T1DM risk was evident even in this comparison across sibling pairs. Further work on past UVR exposure and related factors such as skin pigmentation is required.
African, Asian or Indian enigma, the East Asian Helicobacter pylori: facts or medical myths
Authors: GRAHAM David Y , LU Hong , YAMAOKA Yoshio
Published: April 2009

Helicobacter pylori is etiologically related to peptic ulcer disease and gastric adenocarcinomas. Reports of geographical enigmas (African, Asian, Indian and Costa Rican enigmas) are based on perceptions that clinical presentations in a population or region are not as the authors expected. We discuss the background for these enigmas and examine the evidence whether they are real or are medical myths. The African enigma was challenged almost as soon as it was proposed and recent analyses of endoscopic data have confirmed it is a myth, as H. pylori‐related diseases occur in Africa at the expected frequencies. The Asian and Indian enigmas relate to gastric cancer and peptic ulcers, respectively, and when one takes the patterns of gastritis in the different regions, these enigmas disappear. The pattern of gastritis underlies and predicts the clinical outcome and the predominant pattern of gastritis has been observed to change much more rapidly than can be accounted for by changes in host genetics. There is also no evidence that these changes relate to changes in the predominant H. pylori strain. The factors that link most closely to preventing an atrophic corpus are environmental, with food preservation and diet currently assuming the most prominent roles. This focus on diseases (cancer vs duodenal ulcers) instead of the underlying patterns of gastritis has fostered, and possibly helped to perpetuate, these mythical enigmas. We suggest that a better strategy would be to focus on the pathogenesis of underlying histopathologic differences which could also lead to the identification of specific chemoprevention strategies.
Bile acids and insulin resistance: implications for treating nonalcoholic fatty liver disease
Authors: WEI Jue , QIU De Kai , MA Xiong
Published: April 2009

Nonalcoholic fatty liver disease is characterized by an accumulation of excess triglycerides in hepatocytes, and insulin resistance is now considered the fundamental operative mechanism throughout the prevalence and progression of the disease. Besides their role in dietary lipid absorption and cholesterol homeostasis, evidence has accumulated that bile acids are also signaling molecules that play two important roles in glucose and lipid metabolism: in the nuclear hormone receptors as farnesoid X receptors (FXR), as well as ligands for G‐protein‐coupled receptors TGR5. The activated FXR‐SHP pathway regulates the enterohepatic recycling and biosynthesis of bile acids and underlies the down‐regulation of hepatic fatty acid and triglyceride biosynthesis and very low density lipoprotein production mediated by sterol‐regulatory element‐binding protein‐1c. The bile acid‐TGR5‐cAMP‐D2 signaling pathway in human skeletal muscle in the fasting–feeding cycle increases energy expenditure and prevents obesity. Therefore, a molecular basis has been provided for a link between bile acids, lipid metabolism and glucose homeostasis, which can open novel pharmacological approaches against insulin resistance and nonalcoholic fatty liver disease.
Clinical study of the relationship between inflammatory bowel diseases and colorectal neoplasms
Authors: ZHAO Yu Jie , YUAN Yao Zong
Published: April 2009

OBJECTIVE:   To investigate the incidence of colorectal cancer in inflammatory bowel disease (IBD) patients and its risk factors.

METHODS:   Data on 513 patients in the last 10 years from Ruijin Hospital were collected. Their medical histories were put in database and analyzed including their socio‐demographic features, pathogenetic conditions, diagnostic methods, possible related risk factors, treatment and outcome.

RESULTS:   Among the 513 were 242 with ulcerative colitis (UC), among whom four patients developed cancers and four had precancerous lesions. None of the 271 CD patients developed cancer. The incidence of both cancer and precancerosis in the UC patients was 1.65%. Through multifactorial logistic regression analysis, loss of weight, other disease complications and frequent relapses were proved to be the most probable risk factors.

CONCLUSION:   The incidence of IBD has kept on rising in recent years. Clinically, UC patients have more probability of developing colorectal cancer than CD patients. The main risk factors of developing colorectal cancer in UC patients are frequent relapses, weight loss and other complications.
Hepatitis B virus DNA in patients with hepatitis B‐related liver cirrhosis with or without hepatocellular carcinomas: a matched case‐control study
Authors: XU Jing , LIN Yong , WANG Yi Ping , CHEN Yue Xiang , SHI Bin , LU Jian , XIE Wei Fen
Published: April 2009

OBJECTIVE:  The relationship between serum viremia and the development of hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV)‐related cirrhosis remains unclear. We aimed at calculating odds ratios (OR) for the presence of HCC over a range of HBV DNA levels in these patients.

METHODS:  Patients were identified retrospectively and 155 pairs of matched, treatment‐naive HBV‐related cirrhotic patients with and without HCC were recruited. Their serum HBV DNA levels were measured at HCC diagnosis, or at the equivalent age in non‐HCC patients, and correlations between the presence of HCC and different DNA levels were calculated using conditional logistic regression.

RESULTS:  The median HBV DNA level was significantly higher in HCC patients than in non‐HCC patients (5.15 vs 4.83 log10 copies/mL, P = 0.024). The overall OR for HCC in patients with HBV DNA ≥ 3 log10 copies/mL was 2.13, compared with patients with levels <3 log10 copies/mL. Compared with patients with <3 log10 copies/mL, the OR for HCC were 2.39 and 2.61 for patients with 4 to <5 and 5 to <6 log10 copies/mL, respectively, while the OR for DNA levels of ≥6 log10 copies/mL were not significantly different.

CONCLUSION:  In HBV‐related cirrhosis, a detectable serum HBV DNA was associated with the presence of HCC, but the likelihood of having HCC did not successively increase with increasing serum HBV DNA levels: patients with serum HBV DNA levels between 4 and <6 log10 copies/mL were most likely to present with HCC.
Chromosome numbers of three Calligonum species (Polygonaceae)
Authors: Sabirhazi Gulnur , Pan Bo‐Rong
Published: April 2009

The chromosome number 2n=36 for Calligonum korlaense Z. M. Mao and the chromosome number 2n=18 for Calligonum yengisaricum Z. M. Mao and Calligonum ruoqiangense Liou f. is reported for the first time.
Carex yunyiana sp. nov. (Cyperaceae) from Zhejiang, China
Authors: Jin Xiao‐Feng
Published: April 2009

Carex yunyiana X. F. Jin & C. Z. Zheng, a new species of Carex L. (Cyperaceae) is described from Zhejiang, eastern China. The new species has solitary, terminal, androgynous spikes, pale green pistillate glumes, 3 stigmas, and belongs to Carex subgen. Carex sect. Rhizopodae. It is allied to C. densicaepitosa, which only grows in the Longsheng County of Guangxi Zhuangzu Autonomous Region. However, it differs in having perigynia compressed–trigonous, obovoid, and acutely constricted to a short beak, while the achenes are loosely enveloped, broadly obovoid, trigonous or quadrangular, excavated on lateral surfaces, and evidently stipitate at base. A key to the species of Carex sect. Rhizopodae and a map showing their distribution is also provided.
Schiedeella jean‐mulleri sp. nov. and S. esquintlensis sp. nov. (Orchidaceae, Stenorrhynchidinae) from Guatemala
Authors: Szlachetko Dariusz L. , Rutkowski Piotr , Mytnik‐Ejsmont Joanna
Published: April 2009

Two new species of the genus Schiedeella Schltr. (Orchidaceae), S. jean‐mulleri Szlach., Rutk. & Mytnik and S. esquintlensis Szlach., Rutk. & Mytnik, are described and illustrated. Their taxonomic position is briefly discussed.
Musa×georgiana, a new intersectional hybrid banana with edible banana breeding relevance and ornamental potential
Authors: Wallace Richard , Häkkinen Markku
Published: April 2009

Within the genus Musa (Musaceae) there are five sections. One of these sections is Musa (formerly called Eumusa), which possess predominately pendant inflorescences and are responsible for the production of edible bananas which are of great importance around the world as a food source. Another section of the genus Musa is Rhodochlamys. Most members of this section possess erect inflorescences with brightly colored bracts and are grown mainly for their ornamental value. Intersectional hybrids between the sections Musa and Rhodochlamys have been reported in the past but these hybrids were not characterized or described in any detail by the authors. In this manuscript a new intersectional hybrid banana, Musa×georgiana Rich. H. Wallace hyb. nov. grown in Richmond Hill, Georgia, USA is described and illustrated. The plant has as its maternal parent, Musa balbisiana, a member of M. sect. Musa and one of the seeded ancestors of edible bananas. The paternal parent is Musa velutina, a brightly coloured member of M. sect. Rhodochlamys, grown worldwide for its ornamental value. The resulting hybrid, M.×georgiana, provides useful information for banana breeding programs around the world and has ornamental potential as well. In light of the pest and disease pressure edible bananas are experiencing, the incorporation of genetic resources from other members of the genus is becoming increasingly important in the development of new hybrid edible bananas. A comparison of the characteristics of M.×georgiana with those of the parent species is provided.
The associated markers and their limitations for the primary screening of HCV carriers in public health examination
Authors: Miyazaki Teruo , Honda Akira , Ikegami Tadashi , Hara Takashi , Saitoh Yoshifumi , Hirayama Takeshi , Doy Mikio , Matsuzaki Yasushi
Published: April 2009

Aim:  Although the anti‐hepatitis C virus (HCV) antibody test has been recommended to the whole Japanese population, most countries have not implemented it. The present study aims to re‐evaluate the usefulness of markers examined in the general health examination for the initial screening of HCV carriers.

Methods:  Of the overall population, 25 142 individuals (8876 males, 16 266 females) participated in health examinations with HCV tests in 2005, and the most commonly associated markers for HCV‐positive subjects were explored by multivariate analysis, based on blood biochemical, physical, sphygmomanometric and hematological parameters. Thereafter, the efficiencies of the markers were estimated from a total population of 85 013 individuals (29 502 males, 55 511 females) in 2003–2005.

Results:  The most significantly associated markers for HCV positivity were aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Optimal limits of ALT and AST by receiver–operator characteristic (ROC) analysis were 24 and 27 IU (male, 33 and 28 IU; female, 22 and 26 IU), respectively. However, one‐quarter of HCV carriers were not found to be positive using the optimal limits of aminotransferases.

Conclusion:  The present study confirmed the limitation of serum aminotransferase levels as markers of HCV for primary screening. Therefore, at present, an anti‐HCV antibody test is required for the efficient screening of HCV carriers in all health examinations.
Blood Lactate Concentrations in Anesthetized Dogs with Intracranial Disease
Authors: Sullivan L. A. , Campbell V. L. , Klopp L. S. , Rao S.
Published: April 2009

Background: The importance of blood lactate concentrations in dogs with intracranial disease has not been established, despite frequently observed hyperlactatemia in dogs undergoing general anesthesia for advanced imaging, surgery, or both.

Hypothesis: Blood lactate concentrations are elevated in anesthetized dogs with intracranial disease, compared with dogs with intervertebral disc disease (IVDD).

Animals: Eighty‐five hospitalized dogs undergoing advanced imaging, surgery, or both for primary neurologic disease; 30 with intracranial disease; 55 with IVDD.

Methods: Retrospective study. Age, breed, neurologic diagnosis, time from anesthesia induction to measurement of blood lactate, blood lactate concentration under anesthesia, and concurrently measured heart rate, mean arterial pressure, PCV, arterial hemoglobin oxygen saturation, and arterial partial pressure of oxygen were included in a multivariable linear regression analysis.

Results: Dogs with meningioma (adjusted mean lactate 2.99 mmol/L, 95% CL 2.21–4.05, P < 0.0001) and hydrocephalus (adjusted mean lactate 1.5 mmol/L, 95% CL 0.99–2.27, P= 0.003) had higher blood lactate concentrations compared with dogs with IVDD (adjusted mean lactate 0.79 mmol/L, 95% CL 0.6–1.04). Only dogs with meningioma had clinically important hyperlactatemia (>2.5 mmol/L).

Conclusions: Prospective studies are warranted to determine the degree and clinical importance of high blood lactate concentrations in dogs with intracranial disease.
Risk Factors for Equine Postoperative Ileus and Effectiveness of Prophylactic Lidocaine
Authors: Torfs S. , Delesalle C. , Dewulf J. , Devisscher L. , Deprez P.
Published: April 2009

Background:Postoperative ileus (POI) is a frequent and often fatal complication of colic surgery. Reliably effective treatments are not available.

Objectives:To determine risk factors and protective factors associated with POI, and to assess the effect of lidocaine IV on short‐term survival.

Animals:One hundred and twenty‐six horses that underwent small intestinal colic surgery and that survived for at least 24 hours postoperatively.

Methods:Retrospective cross‐sectional study. The association of 31 pre‐, intra‐, and postoperative variables with POI and the association of lidocaine treatment with short‐term survival were investigated. Associations were evaluated with univariable logistic regression models, followed by multivariable analysis.

Results:Significant associations of high heart rate (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.03–1.08), the presence of more than 8 L of reflux at admission (OR = 3.02, 95% CI 1.13–8.02) and the performance of a small intestinal resection (OR = 2.46, 95% CI 1.15–5.27) with an increased probability of POI were demonstrated. Prophylactic lidocaine treatment was significantly associated with a reduced incidence of POI (OR = 0.25, 95% CI 0.11–0.56). Lidocaine treatment was also significantly associated with enhanced short‐term survival (OR = 0.30, 95% CI 0.09–0.98).

Conclusions and Clinical Importance:The variables associated with an increased risk of POI can be useful in identifying horses at risk of POI and in providing a more accurate prognosis. The results are supportive for lidocaine IV as an effective prokinetic treatment after small intestinal colic surgery.
Evaluation of Alternatives for Two-Dimensional Linear Cascade Facilities
Authors: Kodzwa Paul M. , Vicharelli Amanda , Medic Gorazd , Elkins Christopher J. , Eaton John K. , Laskowski Gregory M. , Durbin Paul A.
Published: April 2009

This paper presents two low-cost alternatives for turbine blade surface heat transfer and fluid dynamics measurements. These models embody careful compromises between typical academic and full-scale turbomachinery experiments and represent a comprehensive strategy to develop experiments that can directly test shortcomings in current turbomachinery simulation tools. A full contextual history of the wide range of approaches to simulate turbine flow conditions is presented, along with a discussion of their deficiencies. Both models are simplifications of a linear cascade: the current standard for simulating two-dimensional turbine blade geometries. A single passage model is presented as a curved duct consisting of two half-blade geometries, carefully designed inlet and exit walls and inlet suction. This facility was determined to be best suited for heat transfer measurements where minimal surface conduction losses are necessary to allow accurate numerical model replication. A double passage model is defined as a single blade with two precisely designed outer walls, which is most appropriate for flow measurements. The design procedures necessary to achieve a desired flow condition are discussed.
Numerical Investigations of Localized Vibrations of Mistuned Blade Integrated Disks (Blisks)
Authors: Klauke T. , Kühhorn A. , Beirow B. , Golze M.
Published: April 2009

Blade-to-blade variations of bladed disk assemblies result in local zoning of vibration modes as well as amplitude magnifications, which primarily reduces the high cycle fatigue life of aeroengines. Criteria were introduced to determine the level of these mode localization effects depending on various parameters of a real high pressure compressor blisk rotor. The investigations show that blade vibration modes with lower interblade coupling, e.g., torsion modes or modes with high numbers of nodal diameter lines, have a significantly higher sensitivity to blade mistuning, which can be characterized by the higher percentage of blades on the total blisk strain energy.
Time-Accurate Predictions for a Fully Cooled High-Pressure Turbine Stage—Part II: Methodology for Quantifications of Prediction Quality
Authors: Haldeman C. W. , Dunn M. G. , Southworth S. A. , Chen J.-P. , Heitland G. , Liu J.
Published: April 2009

The aerodynamics of a fully cooled, axial, single stage high-pressure turbine operating at design corrected conditions of corrected speed, flow function, and stage pressure ratio has been investigated experimentally and computationally and presented in Part I of this paper. In that portion of the paper, flow-field predictions obtained using the computational fluid dynamics codes Numeca’s FINE/TURBO and the code TURBO were obtained using different design methodologies that approximated the fully-cooled turbine stage in different ways. These predictions were compared to measurements obtained using the Ohio State University Gas Turbine Laboratory Turbine Test Facility, in a process that was essentially a design methodology validation study, instead of a computational methodology optimization study. The difference between the two is that the designers were given one chance to use their codes (as a designer would normally do) instead of using the existing data to fine-tune their grids/methodologies by doing grid studies and changes in the turbulence models employed. Part I of this paper showed differing results from the two solvers, which appeared to be mainly dependent on the differences in grid resolution and/or modeling features selected by the code users. Examining these occurrences points to places where the design methodology could be improved, but it became clear that metrics were needed to compare overall performance of each approach. In this part of the paper, three criteria are proposed for measuring overall prediction quality of the unsteady predictions, which include the unsteady envelope size, envelope shape, and power spectrum. These measures capture the main characteristics of the unsteady data and allow designers to use the criteria of most interest to them. In addition, these can be used to track how well predictions improve over time as grid resolutions and modeling techniques change.
Effect of Inlet Flow Angle on Gas Turbine Blade Tip Film Cooling
Authors: Gao Zhihong , Narzary Diganta , Mhetras Shantanu , Han Je-Chin
Published: April 2009

The influence of incidence angle on film-cooling effectiveness is studied for a cutback squealer blade tip. Three incidence angles are investigated −0 deg at design condition and ±5 deg at off-design conditions. Based on mass transfer analogy, the film-cooling effectiveness is measured with pressure sensitive paint techniques. The film-cooling effectiveness distribution on the pressure side near tip region, squealer cavity floor, and squealer rim tip is presented for the three incidence angles at varying blowing ratios. The average blowing ratio is controlled to be 0.5, 1.0, 1.5, and 2.0. One row of shaped holes is provided along the pressure side just below the tip; two rows of cylindrical film-cooling holes are arranged on the blade tip in such a way that one row is offset to the suction side profile and the other row is along the camber line. The pressure side squealer rim wall is cut near the trailing edge to allow the accumulated coolant in the cavity to escape and cool the tip trailing edge. The internal coolant-supply passages of the squealer tipped blade are modeled similar to those in the GE-E3 rotor blade. Test is done in a five-blade linear cascade in a blow-down facility with a tip gap clearance of 1.5% of the blade span. The Mach number and turbulence intensity level at the cascade inlet were 0.23 and 9.7%, respectively. It is observed that the incidence angle affects the coolant jet direction on the pressure side near tip region and the blade tip. The film-cooling effectiveness distribution is also altered. The peak of laterally averaged effectiveness is shifted upstream or downstream depending on the off-design incidence angle. The film cooling effectiveness inside the tip cavity can increase by 25% with the positive incidence angle. However, in general, the overall area-averaged film-cooling effectiveness is not significantly changed by the incidence angles in the range of study.
Reduced-Order Model of a Bladed Rotor With Geometric Mistuning
Authors: Sinha Alok
Published: April 2009

This paper deals with the development of an accurate reduced-order model of a bladed disk with geometric mistuning. The method is based on vibratory modes of various tuned systems and proper orthogonal decomposition of coordinate measurement machine data on blade geometries. Results for an academic rotor are presented to establish the validity of the technique.
Effects of Compressor Tip Injection on Aircraft Engine Performance and Stability
Authors: Horn Wolfgang , Schmidt Klaus-Jürgen , Staudacher Stephan
Published: April 2009

This analytical study discusses the system aspects of active stability enhancement using mass flow injection in front of the rotor blade tip of a high pressure compressor. Tip injection is modeled as a recirculating bleed in a performance simulation of a commercial turbofan engine. A map correction procedure accounts for the changes in compressor characteristics caused by injection. The correction factors are derived from stage stacking calculations, which include a simple correlation for stability enhancement. The operational characteristic of the actively controlled engine is simulated in steady and transient states. The basic steady-state effect consists of a local change in mass flow and a local increase in gas temperature. This alters the component matching in the engine. The mechanism can be described by the compressor-to-turbine flow ratio and the injection temperature ratio. Both effects reduce the cycle efficiency resulting in an increased turbine temperature and fuel consumption at constant thrust. The negative performance impact becomes negligible if compressor recirculation is only employed at the transient part power and if valves remain closed at the steady-state operation. Detailed calculations show that engine handling requirements and temperature limits will still be met. Tip injection increases the high pressure compressor stability margin substantially during critical maneuvers. The proposed concept in combination with an adequate control logic offers promising benefits at transient operation, leading to an improvement potential for the overall engine performance.
Spike and Modal Stall Inception in an Advanced Turbocharger Centrifugal Compressor
Authors: Spakovszky Z. S. , Roduner C. H.
Published: April 2009

In turbocharger applications, bleed air near the impeller exit is often used for secondary flow systems to seal bearing compartments and to balance the thrust load on the bearings. There is experimental evidence that the performance and operability of highly-loaded centrifugal compressor designs can be sensitive to the amount of bleed air. To investigate the underlying mechanisms and to assess the impact of bleed air on the compressor dynamic behavior, a research program was carried out on a preproduction, 5.0 pressure ratio, high-speed centrifugal compressor stage of advanced design. The investigations showed that bleed air can significantly reduce the stable flow range. Compressor rig experiments, using an array of unsteady pressure sensors and a bleed valve to simulate a typical turbocharger environment, suggest that the path into compression system instability is altered by the bleed flow. Without the bleed flow, the prestall behavior is dominated by short-wavelength disturbances, or so called “spikes,” in the vaneless space between the impeller and the vaned diffuser. Introducing bleed flow at the impeller exit reduces endwall blockage in the vaneless space and destabilizes the highly-loaded vaned diffuser. The impact is a 50% reduction in stable operating range. The altered diffuser characteristic reduces the compression system damping responsible for long-wavelength modal prestall behavior. A four-lobed backward traveling rotating stall wave is experimentally measured in agreement with calculations obtained from a previously developed dynamic compressor model. In addition, a self-contained endwall blockage control strategy was employed, successfully recovering 75% of the loss in surge-margin due to the bleed flow and yielding a one point increase in adiabatic compressor efficiency.
Surface Shear Stress and Pressure Measurements in a Turbine Cascade
Authors: Holley Brian M. , Langston Lee S.
Published: April 2009

To further the understanding of secondary flow loss, a set of surface measurements is presented for a planar turbine cascade tested at low Mach number (maximum of 0.23) and at an inlet axial chord Reynolds number of 5.9×105. The endwall and airfoil surface measurements are of skin friction, limiting streamline direction, and static pressure. An oil film interferometry measurement technique applied to the endwall and airfoil surfaces (at some 2000 locations) provides an extensive passage surface map of skin friction values and limiting streamline topology. Measurements of pressures on the same passage surfaces are also presented, resulting in a complete picture of endwall and airfoil surface pressure and shear.
A Comparison of the Flow Structures and Losses Within Vaned and Vaneless Stators for Radial Turbines
Authors: Simpson A. T. , Spence S. W. T. , Watterson J. K.
Published: April 2009

This paper details the numerical analysis of different vaned and vaneless radial inflow turbine stators. Selected results are presented from a test program carried out to determine performance differences between the radial turbines with vaned stators and vaneless volutes under the same operating conditions. A commercial computational fluid dynamics code was used to develop numerical models of each of the turbine configurations, which were validated using the experimental results. From the numerical models, areas of loss generation in the different stators were identified and compared, and the stator losses were quantified. Predictions showed the vaneless turbine stators to incur lower losses than the corresponding vaned stator at matching operating conditions, in line with the trends in measured performance. Flow conditions at rotor inlet were studied and validated with internal static pressure measurements so as to judge the levels of circumferential nonuniformity for each stator design. In each case, the vaneless volutes were found to deliver a higher level of uniformity in the rotor inlet pressure field.