bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison of the dentin‐removing ability of five root canal instruments
Authors: MOLVEN OLAV
Published: February 2009

Abstract— The dentin‐removing ability of five root canal instruments was studied by enlarging 140 canals drilled in slices cut from young premolars. All canals were operated for two minutes using the instruments with a push and pull motion. The canal openings on both sides of each slice were photographed pre‐ and postoperatively according to a standardized routine. Thirty specimens were also photographed after the first minute of instrumentation. The areas of the canal openings were traced twice, and each tracing was measured twice by a compensating planimeter. The enlargement of each canal opening was then calculated, and the results were analyzed statistically. The results justified a grouping of the tested instruments according to their ability to remove dentin. The most efficient instruments were the Antæose® nerve canal file type K 99 No. 2, length 26 mm and the standardized Kerr root canal file No. 15, style B, length 25 mm, both operated by hand. The second group consisted of the same Antæos file driven by a Racer® contra‐angled handpiece at 1500 rpm and the hand‐powered Hedström® file No. 1, length 23 mm. The third group, exhibiting the lowest dentin removing ability, comprised the Micro‐Méga® broach No. 3, length 21 mm, driven by the Giromatic® contraangled handpiece.
ORIGINAL ARTICLE: Incidence of Antisperm Antibodies in Males with Systemic Autoimmune Diseases
Authors: Shiraishi Yasuko , Shibahara Hiroaki , Koriyama Junko , Hirano Yuki , Okazaki Hitoaki , Minota Seiji , Suzuki Mitsuaki
Published: February 2009

Problem  To investigate if systemic autoimmune diseases could be one of the risk factors for developing antisperm antibodies (ASA) in males.

Method of study  Antisperm antibodies in the sera of 70 males with systemic autoimmune diseases and 80 healthy controls were examined, by using the indirect‐immunobead test (I‐IBT). The sperm immobilization test (SIT) was also performed to detect sperm immobilizing antibodies to the patients who were positive in I‐IBT.

Results  Among 70 males with systemic autoimmune diseases, five were I‐IBT positives, with incidence of 7.1%. However, no positives existed in 80 healthy males. Compared with the healthy controls, the incidence of ASA in males with systemic autoimmune diseases was significantly higher (P = 0.020). None of these five ASA‐positive patients had sperm immobilizing antibodies.

Conclusion  The incidence of ASA in males with systemic autoimmune diseases was significantly higher than in the healthy controls. Systemic autoimmune diseases may be one of the risk factors for developing ASA in men.
The Tudor Coronation Ceremonies in History and Criticism
Authors: Hunt Alice
Published: February 2009

The coronation was one of the most important – and scrutinised – ceremonies of a Tudor monarch's reign. Five coronations took place in sixteenth‐century England, but there is currently no comprehensive history of these ceremonies. Criticism has tended to focus on coronation processions, divorcing them from the sacred service they precede and often presenting them as exercises in royal propaganda. The story of the Tudor coronations has also been co‐opted as part of the more general history of the Protestantisation of ceremonies: the emptying out of ceremony is assumed. But the Tudor coronations remained significant throughout the sixteenth century, and their relationship with power and legitimacy troubled contemporaries far more than has been sometimes been claimed. Revisionist histories now consider continuity as well as change. They treat power as less centralised and less coherent, and recognise the persistence of the idea of sacred monarchy. As such, they demand that we look again at the coronations in all their religious, political and symbolic complexity. This article offers a brief account of the Tudor coronations and the place that state ceremonies have occupied in recent and past criticism. It also suggests how future research might build on a fresh understanding of the role of ceremonies in early modern England.
Erectile Dysfunction in End-Stage Liver Disease Men
Authors: Huyghe Eric , Kamar Nassim , Wagner Fabien , Capietto Aude-Hélène , El-Kahwaji Labib , Muscari Fabrice , Plante Pierre , Rostaing Lionel
Published: February 2009

Introduction

In men, erectile dysfunction (ED) is an important issue. Data concerning ED in men with end-stage liver disease (ESLD) is limited, and the risk factors for ED in this population are still unknown.

Aims

To determine the prevalence, timescale, and risk factors for ED in ESLD patients candidates to liver transplantation.

Methods

Patients candidates for a liver transplantation were asked to participate in a mailed survey about sexual function. Among the 123 eligible men, 98 (84%) agreed to complete the questionnaire.

Main Outcome Measures

The quality of erection was evaluated using the five-item International Index of Erectile Function (IIEF-5) score, and satisfaction for sexuality, using the patient-baseline Treatment-Satisfaction Scale (TSS) score. Other questions also focused on patient perception of changes over time.

Results

On the overall population, 28 patients (29%) were nonsexually active. Among the 70 patients who were sexually active, 52 patients (74%) had ED. Regarding the development of ED, 50% of the patients perceived that a deterioration of erectile function occurred within the six previous months. The absence of sexual activity was more frequent in hepatitis B or C patients (P = 0.02). The risk factors for ED were alcohol intake (P = 0.03), tobacco use (P = 0.03), and cardiovascular disease (P = 0.004). The significant risk factors for having a low TSS score were having viral hepatitis (P = 0.01), and cardiovascular disease (P = 0.01).

Conclusion

Population of men with ESLD who are candidates for a liver transplantation is characterized by a high frequency of lack of sexual activity, and by a high prevalence of ED and should be targeted by interventions to improve sexual functioning. These preliminary data need further validation in prospective trial using more comprehensive questionnaires.
Targeting Vascular Structure for the Treatment of Sexual Dysfunction
Authors: Hale Taben M , Hannan Johanna L , Carrier Serge , DeBlois Denis , Adams Michael A.
Published: February 2009

Introduction

Erectile dysfunction (ED) and cardiovascular disease often coexist and have many common risk factors. In hypertension, the structure of blood vessels is modified such that there is an increase in medial wall thickness relative to lumen size. Certain antihypertensive agents have been found to induce a regression of vascular structure such that a “hypertensive” vessel appears phenotypically more like that from a normotensive.

Aim

To provide an update on the findings to date on the impact of vascular remodeling on erectile function.

Main Outcome Measures

Review of peer reviewed literature related to vascular remodeling induced by antihypertensive agents and the potential impact on sexual function.

Methods

A literature review was performed on clinical and experimental evidence regarding the association between cardiovascular disease and ED, the impact of vascular remodeling on these conditions, the impact of antihypertensive therapy on ED, and the mechanisms of antihypertensive drug-induced remodeling.

Results

There is increasing evidence that ED may be an early marker for progressing cardiovascular disease. Certain antihypertensive agents have beneficial effects on both vascular structure and erectile function. The major site of resistance in the penile vasculature occurs at the level of the pudendal artery. Although structural remodeling has not yet been investigated in this vessel specifically, antihypertensive drugs have been shown to induce remodeling of the pudendal-penile vasculature and cavernosal arteries. Antihypertensive drug-induced vascular remodeling can be characterized by a decrease in the ratio of wall thickness to lumen diameter, and may result from vascular smooth muscle cell apoptosis, rearrangement of cells around a smaller lumen, and/or changes in the extracellular matrix composition depending on the vessel type.

Conclusions

Determining the mechanisms involved in antihypertensive drug-induced vascular remodeling in the pudendal vasculature may provide novel targets for the treatment of ED.
Corporal “Snake” Maneuver: Corporoglanular Shunt Surgical Modification for Ischemic Priapism
Authors: Burnett Arthur L. , Pierorazio Phillip M.
Published: February 2009

Introduction

Current surgical shunting procedures for major ischemic priapism do not always effectively resolve acute presentations of this disorder.

Aim

To evaluate a modification of the Al-Ghorab distal penile corporoglanular shunt surgery for ischemic priapism.

Methods

Three previously potent men (48, 43, 40 years of age) presented with major ischemic priapism episodes (5, 2, and 6 days in duration, respectively), which were refractory to clinical management including sympathomimetic intracavernosal treatments, intracorporal aspiration and saline irrigation, and penile shunt surgery attempts. We offered a surgical technique for facilitating corporal blood evacuation by retrograde insertion of a cavernosal dilator through the excised tunical windows of the distal corpora cavernosa after transglanular incision.

Main Outcome Measures

Clinical evaluation of priapism resolution and erection recovery.

Results

All men achieved successful resolution of priapism, with meaningful erection recovery assessable in one man.

Conclusions

The modified Al-Ghorab corporoglanular shunt surgery appears to offer an advantageous management approach to resolve ischemic priapism, particularly for cases refractory to first-line management.
CONSTRUCTING PARALLEL SIMULATION EXERCISES FOR ASSESSMENT CENTERS AND OTHER FORMS OF BEHAVIORAL ASSESSMENT
Authors: BRUMMEL BRADLEY J. , RUPP DEBORAH E. , SPAIN SETH M.
Published: February 2009

Assessment centers rely on multiple, carefully constructed behavioral simulation exercises to measure individuals on multiple performance dimensions. Although methods for establishing parallelism among alternate forms of paper‐and‐pencil tests have been well researched (i.e., to equate tests on difficulty such that the scores can be compared), little research has considered the why and how of parallel simulation exercises. This paper extends established procedures for constructing parallel test forms to dimension‐based behavioral simulations. We discuss reasons for establishing comparable, alternate simulation forms and discuss the issues raised when applying traditional procedures to simulation exercises. After proposing a set of guidelines for establishing alternate forms among simulations, we apply these guidelines to simulations used in an operational assessment center.
Dermal arteritis of the nasal philtrum: surgery as an alternative to long‐term medical therapy in two dogs
Authors: Pratschke K. M. , Hill P. B.
Published: February 2009

Two dogs were presented with dermal arteritis of the nasal philtrum associated with repeated episodes of bleeding. Described treatment for this condition consists of long‐term, usually life‐long medication with various combinations of immune suppressant and anti‐inflammatory medication. This paper describes a novel surgical approach to the condition that induced long‐term remission in both cases.
Comparisons of Chemical and Physical Properties of Catfish Oils Prepared from Different Extracting Processes
Authors: Sathivel S. , Yin H. , Prinyawiwatkul W. , King J.M.
Published: February 2009

ABSTRACT:  Four different catfish oil extraction processes were used to extract oil from catfish viscera: process CF1 involved a mixture of ground catfish viscera and water, no heat treatment, and centrifugation; process CF2 involved ground catfish viscera (no added water), heat treatment, and centrifugation; process CF3 involved a mixture of ground catfish viscera and water, heat treatment, and centrifugation; process CF4 involved ground catfish viscera, enzymatic hydrolysis, and centrifugation. Chemical and physical properties of the resulting of catfish oils were evaluated. The CF4 process recovered significantly higher amounts of crude oil from catfish viscera than the other 3 extraction methods. The CF4 oil contained a higher percent of free fatty acid and peroxide values than CF1, CF2, and CF3 oils. Oleic acid in catfish oil was the predominant fatty acid accounting for about 50% of total fatty acids. Weight loss of oils increased with increasing temperatures between 250 and 500 °C. All the catfish oil samples melted around −32 °C regardless of the extraction methods. The flow behavior index of all the oil samples was less than 1, which indicated that the catfish oils exhibited non‐Newtonian fluid behavior. The apparent viscosity at −5 and 0 °C was significantly higher (P < 0.05) than those at 5, 10, 15, 20, 25, and 30 °C. The average magnitude of activation energy for apparent viscosity of the oil was higher for CF2 than CF1, CF3, and CF4.
Effects of Yolk Contamination, Shearing, and Heating on Foaming Properties of Fresh Egg White
Authors: Wang G. , Wang T.
Published: February 2009

ABSTRACT:  A series of experiments were conducted to evaluate effects of yolk contamination, shearing, and thermal treatment on foaming properties of liquid egg white. Samples obtained from industrial processing were also evaluated. Whipping and purging methods were both used to assess their effectiveness and sensitivity in evaluating foaming. A concentration as low as 0.022% (as‐is basis) of yolk contamination caused significant reductions in foaming capacity and foaming speed. The neutral lipid fraction of egg yolk caused the major detrimental effect on foaming, and phospholipids fraction did not give significant foaming reduction at a concentration as high as 0.1%. High‐speed and short‐time shearing caused no apparent damage but longer shearing time significantly impaired foaming. Heat‐induced foaming change is a function of temperature and holding time. Foaming was significantly reduced at a temperature of 55 °C for 10 min, whereas it did not change up to 3 min at a heating temperature of 62 to 64 °C. Industrial processing steps (pumping, pipe transfer, and storage) did not produce negative effects on foaming of the final products and the controlled pasteurization was actually beneficial for good foaming performance. Therefore, yolk contamination of the egg white was the major factor in reducing foaming properties of the white protein.
In vitroAntilisterial Effects of Citrus Oil Fractions in Combination with Organic Acids
Authors: Friedly E.C. , Crandall P.G. , Ricke S.C. , Roman M. , O'Bryan C. , Chalova V.I.
Published: February 2009

ABSTRACT: The objectives of this study were to screen activity of citrus essential oil fractions (EOs) alone and in combination with organic acids against 2 species ofListeria. Five citrus EOs were initially screened by disc diffusion assay for antibacterial activity. Cold pressed terpeneless Valencia orange oil (CP terpeneless oil) had the strongest bacteriostatic (MIC) and bactericidal (MBC) properties at 0.55% and 1.67%, respectively. Four organic acids were tested for effectiveness againstListeria. Citric and malic acids proved to be the most effective with MBC of 1.1% alone. Assays were conducted to determine synergistic effects of EOs and citric or malic acids. There was a significant decrease in MIC and MBC to 0.04% EO plus 0.12% malic or citric acid. EOs from citrus paired with organic acids offer the potential as an all‐natural antimicrobial for improving the safety of all‐natural foods.
Factors associated with functional psychosocial status in first‐episode psychosis
Authors: Lucas Sara K. , Redoblado‐Hodge M. Antoinette , Shores E. Arthur , Brennan John , Harris Anthony
Published: February 2009

Aim: This study aimed to determine which of demographic/premorbid, psychiatric or neuropsychological variables are most closely associated with functional status around the time of diagnosis of first‐episode psychosis. This was with a view to determining factors that should be the focus of intervention in these early stages of illness.

Methods: The Western Sydney First Episode Psychosis Project collected data on young persons (aged 13–25) with newly diagnosed psychosis (n = 92). Psychosocial functional status was measured using the Role Functioning Scale (RFS). Multiple regression analyses were carried out to identify predictors of RFS score from a wide range of predictor variables.

Results: Psychiatric variables accounted for the most variance in RFS score. Positive and Negative Syndrome Scale (PANSS) Negative subscale and Young Mania Rating Scale score were found to be significant individual predictors, with variables from the other domains failing to contribute to the overall model. In separate models, demographic/premorbid and neuropsychological factors weakly related to functional status.

Conclusions: Psychiatric factors were the main influence on psychosocial functioning in first‐episode psychosis at baseline. Evidence suggests the relationships between symptoms, cognition and demographics with function might change over time, depending on the stage of illness being examined.
Initial medical work‐up of first‐episode psychosis: a conceptual review
Authors: Freudenreich Oliver , Charles Schulz S. , Goff Donald C.
Published: February 2009

Aim: To help clinicians carry out a comprehensive, medical diagnostic assessment in first‐episode patients who are suspected of developing schizophrenia.

Methods: Conceptual review of the published work with emphasis on the diagnostic goals of excluding medical causes of psychosis and establishing a medical baseline.

Results: There is no agreed‐upon standard for the initial medical work‐up of first‐episode cases. Excluding secondary causes of schizophrenia requires consideration of likelihood of disease; laboratory test performance; and relevance of positive test results.

Conclusions: We propose a medical work‐up for first‐episode psychosis that combines: (i) broad screening; (ii) exclusion of specific diseases informed by treatability and epidemiology; and (iii) medical baseline measures.
Cost implications of specific and non‐specific treatment for young persons at ultra high risk of developing a first episode of psychosis
Authors: Phillips Lisa J. , Cotton Sue , Mihalopoulos Cathrine , Shih Sophy , Yung Alison R. , Carter Rob , McGorry Patrick D.
Published: February 2009

Aim:Costs associated with mental health treatment for young persons at ‘ultra’ high risk (UHR) of developing a psychotic disorder have not previously been reported. This paper reports cost implications of providing psychological and pharmacological intervention for individuals at UHR for psychosis compared with minimal psychological treatment.

Method:Mental health service costs associated with a randomized controlled trial of two treatments (Specific Preventive Intervention: SPI and Needs‐Based Intervention: NBI) for UHR young persons were estimated and compared at three time points: treatment phase, short‐term follow up and medium‐term follow up.

Results:Although the SPI group incurred significantly higher treatment costs than the NBI group over the treatment phase, they incurred significantly lower outpatient treatment costs over the longer term.

Conclusion:This study indicates that specific interventions designed to treat young persons who are identified as being at UHR of psychosis might be associated with some cost savings compared with non‐specific interventions.
Development of 52 new polymorphic microsatellite markers for the olive flounder, Paralichthys olivaceus
Authors: KIM WOO‐JIN , KANG JUNG‐HA , NAM BO‐HYE , KONG HEE JEONG , PARK EUN‐MI , LEE JEONG‐HO , KIM KYUNG‐KIL , KIM YOUNG‐OK , HAN HYON SOB , CHOI TAE‐JIN , CHEONG JAEHUN
Published: February 2009

We characterized 52 new microsatellite markers isolated from (GT)n and (CT)n microsatellite‐enriched genomic libraries of the olive flounder (Paralichthys olivaceus). All markers were polymorphic, with eight to 30 (mean 15.1) alleles detected in 30 individuals from a single natural population. Observed heterozygosity ranged from 0.20 to 1.0. Segregation analysis within a mapping family revealed non‐amplifying null alleles at six loci. These results indicate that these new microsatellite markers will be useful for population genetic, parentage, and genome mapping studies.
RATES OF RETURN TO EDUCATION IN BOTSWANA: RESULTS FROM THE 2002/2003 HOUSEHOLD INCOME AND EXPENDITURE SURVEY DATA SET
Authors: Siphambe Hk
Published: February 2009

Using the most recent Household Income and Expenditure Survey data (2002/2003), this paper presents current rates of return to education for Botswana. The results show that the rates of return have in general declined by one percentage point on average between the periods as shown in Table 2. If we, however, look at the averages for the different school cycles, the fall in the average rates is quite significant at about six percentage points between the periods. The biggest fall is for secondary education, especially upper secondary education, which fell by 28 percentage points between the periods. The rates of return to tertiary education, however, rose by more than 50 percentage points. Ignoring upper secondary, the pattern of rates of return has remained similar to the results of the study based on the 1993/1994 data. Rates are higher for tertiary education and lower for secondary than for primary education. This results are still consistent with rates of return generally rising with level of education. At policy level, the results continue to support sharing of costs between Government and beneficiaries or their parents especially at tertiary education level. Second, the results indicate the need for the country to continue to vigorously pursue job creation and reorient the education system from emphasis on white collar jobs.

Mincerian earnings function: overall Ψ  Dependent variable (ln monthly earnings)

Variable
Coefficient

Constant
4.08 (321.6)

Education
0.15 (378)**

Experience
0.085 (171.2)**

Experience Squared
−0.001 (−142)**

IM Ratio
−2.12 (3.68)**

R2 (Adjusted)
0.29

Sample Size (n)
5,328

Note: t‐statistics in parenthesis.

Significant at 1% level of significance.
DETERMINANTS OF CHILD NUTRITION IN MALAWI
Authors: Chirwa Ephraim W , Ngalawa Harold Pe
Published: February 2009

This paper investigates factors that determine child malnutrition in Malawi. Measuring child nutrition using anthropometric measures, the study finds that child malnutrition worsens with age until a certain critical age beyond which it starts to improve and that boys are more at risk than girls. We also find evidence that child malnutrition is more prevalent in children that fall sick regularly and in households that draw water from a well, protected or not. In addition, children who come from households that have mother/female household heads who are economically empowered, in terms of being in salaried employment or working in a family business, tend to be better nourished.
ALCOHOL TAXES VS. PREVENTATIVE MEASURES: A THEORETICAL NOTE
Authors: Black Pa
Published: February 2009

The paper assumes that damages in the form of deaths and traumatic injuries caused by alcohol‐related road accidents constitute a significant part of the negative externalities associated with alcohol consumption. It then compares the conventional Pigouvian solution with the impact that a sufficiently high penalty on drunken driving and better law enforcement may have. It is hypothesised that these measures may cause heavy drinkers either to cut back on their consumption of alcohol on occasions when they have to drive a vehicle or to maintain their consumption levels but refrain from driving. The welfare losses are much lower for each of these scenarios and are also carried specifically by those responsible for the negative externality. An attempt is also made to consider how individuals may respond to higher penalties and/or a more effective law enforcement system.
ETHNIC BUSINESS AND ECONOMIC EMPOWERMENT: THE AFRIKANER CASE, 1915‐1970
Authors: Giliomee Hermann
Published: February 2009

The struggle for racial or ethnic group worth is an important socio‐political issue in societies where a minority ethnic group, like the English‐speaking whites in South Africa or the Chinese in Malaysia, dominates the economy but not the political system.

There are two routes to the empowerment of an economically backward group. In the Afrikaner case, economic mobilisation formed part of a general ethnic mobilisation. While the Afrikaner‐controlled state after 1948 massively aided all whites, Afrikaner business increased its market share through serving a niche market. It received little ethnic patronage from the state or assistance from English corporations. A quite different from of advancement is that driven by the state, which imposes on large corporations the obligation to promote the economic empowerment of a racial group. While the first form facilitated the rise of the ethnic group as a whole, the latter one benefited mainly a business and middle class elite that may remain dependent on continuing state support.
NEOCLASSICAL THEORY AND THE TEACHING OF UNDERGRADUATE MICROECONOMICS
Authors: Scerri Mario
Published: February 2009

This paper explores possible reasons for the long and enduring dominance of neoclassical theory over the undergraduate microeconomics textbook. It proposes that those very attributes of neoclassical microeconomics that raise serious theoretical misgivings constitute the basis for the current hegemony of the standard undergraduate textbook. It further discusses the effects of the standard text on the education of economists in developing countries and conditions of the entrenchment of this text in undergraduate teaching. Finally, it looks at the possibilities of the emergence of alternative textbooks both in the centre and in the periphery of the global academic map.
ECONOMIC EVALUATION OF THE PROPOSED ROAD BETWEEN GOBABIS AND GROOTFONTEIN, NAMIBIA
Authors: Pienaar Wj
Published: February 2009

First, a cost‐benefit analysis is presented of reconstructing the existing road section between Gobabis and Otjinene in Namibia.

Second, a cost‐benefit analysis is presented of constructing a new direct road link between Otjinene and Grootfontein, coupled with the above‐mentioned road upgrading between Gobabis and Otjinene as one project. The proposed link will shorten the existing route from GobabisviaWindhoek to Grootfontein by approximately 300 km. The following economic indicators are shown in the two cost‐benefit analyses:(i)Net Present Value,(ii)Benefit/Cost Ratio, and(iii)Internal Rate of Return.

Third, the general economic impact that construction and operation of the entire road will have on non‐road users within Namibia is evaluated. This analysis is divided into two parts: The first part deals with the once‐off income‐multiplier effect triggered by the initial investment in the road, while the second part addresses the recurring income accelerator effect that usage of the road is expected to have within Namibia.
EXPLAINING THE MARKET POWER OF GHANAIAN BANKS1
Authors: Aboagye Q.q. Anthony , Akoena S.k. , Antwi‐asare T.o. , Gockel A.f.
Published: February 2009

A competitive banking system helps lower transaction costs and risks. It also helps make financial markets more efficient. In Ghana however, observers believe that the banking industry is not competitive and point to the huge spread between bank lending and borrowing rates as evidence. The Ghanaian banking industry is analysed for evidence of market power by computing the Lerner Index of banks using quarterly data from 2001 to 2006. The evidence is that Ghanaian banks possess market power. Factors that significantly explain the market power of Ghanaian banks are: bank size, efficiency of banks with respect to staff costs, the macroeconomic environment and time.
Sentinel lymph node biopsy in patients with a needle core biopsy diagnosis of ductal carcinoma in situ: is it justified?
Authors: Doyle B , Al-Mudhaffer M , Kennedy M M , O’Doherty A , Flanagan F , McDermott E W , Kerin M J , Hill A D , Quinn C M
Published: February 2009

Background:

The incidence of ductal carcinoma in situ (DCIS) has increased markedly with the introduction of population-based mammographic screening. DCIS is usually diagnosed non-operatively. Although sentinel lymph node biopsy (SNB) has become the standard of care for patients with invasive breast carcinoma, its use in patients with DCIS is controversial.

Aim:

To examine the justification for offering SNB at the time of primary surgery to patients with a needle core biopsy (NCB) diagnosis of DCIS.

Methods:

A retrospective analysis was performed of 145 patients with an NCB diagnosis of DCIS who had SNB performed at the time of primary surgery. The study focused on rates of SNB positivity and underestimation of invasive carcinoma by NCB, and sought to identify factors that might predict the presence of invasive carcinoma in the excision specimen.

Results:

7/145 patients (4.8%) had a positive sentinel lymph node, four macrometastases and three micrometastases. 6/7 patients had invasive carcinoma in the final excision specimen. 55/145 patients (37.9%) with an NCB diagnosis of DCIS had invasive carcinoma in the excision specimen. The median invasive tumour size was 6 mm. A radiological mass and areas of invasion <1 mm, amounting to “at least microinvasion” on NCB were predictive of invasive carcinoma in the excision specimen.

Conclusions:

SNB positivity in pure DCIS is rare. In view of the high rate of underestimation of invasive carcinoma in patients with an NCB diagnosis of DCIS in this study, SNB appears justified in this group of patients.
Evaluating the knowledge base for expanding low-trophic-level fisheries in Atlantic Canada
Authors: Anderson Sean C. , Lotze Heike K. , Shackell Nancy L.
Published: February 2009

Over the last two decades, low-trophic-level fisheries have rapidly expanded in Atlantic Canada, largely compensating for collapsed groundfisheries; however, concerns have been raised regarding the limited background knowledge for many newly targeted species and their overexploitation in other regions. Using government stock assessments, we evaluated the amount of information available to assess population, fisheries, and ecosystem status in emerging (new since 1988), developing (expanding since 1988), and established fisheries on the Scotian Shelf. Emerging fisheries had significantly lower levels of population knowledge than developing and established fisheries. Importantly, knowledge was often lacking in basic population parameters such as growth rates, current biomass, and geographic range. In contrast, ecosystem knowledge, such as habitat disruption and recovery, was higher in emerging than established fisheries. Overall, quantitative knowledge was positively related to fishery value and greatest for 30- to 100-year-old fisheries. Although the number of government and general scientific publications greatly increased since 1990 for developing and established fisheries, publications for emerging fisheries remained at low levels. Emerging fisheries represent important socio-economic value in Atlantic Canada but may be progressing too rapidly for adequate knowledge to be gained, presenting a risk for their sustainable development.
Establishing highly accurate production-age data using the tree-ring technique of crossdating: a case study for Pacific geoduck (Panopea abrupta)
Authors: Black Bryan A. , Gillespie Darlene C. , MacLellan Shayne E. , Hand Claudia M.
Published: February 2009

We apply the tree-ring technique of crossdating to generate highly accurate age data and evaluate error in annual growth increment (annual growth zone) counts for long-lived Pacific geoduck ( Panopea abrupta ) in the Tree Nob Islands, northern British Columbia, Canada. Crossdating is the most fundamental procedure of tree-ring analysis and is based on the tendency of environmental variability to synchronize the growth of all individuals at a given site. By crossmatching these synchronous growth “bar codes”, all growth increments can be correctly identified and assigned the correct calendar year, including the innermost year of recruitment. In this analysis, a total of 432 geoduck individuals were aged using crossdating methods as well as annual growth increment counts. The entire crossdating process was completed using visual techniques, requiring no additional equipment beyond a microscope or microprojector. When compared with crossdated ages, growth increment counts consistently underaged Pacific geoduck, particularly in the oldest individuals. These inaccuracies obscured major recruitment pulses and underestimated the rarity of strong recruitment events. To date, crossdating has been used to develop growth chronologies in a variety of marine and freshwater bivalve and fish species, but no study has demonstrated how the technique can be used to dramatically and economically improve accuracy in age data.
Iteroparity in Columbia River summer-run steelhead (Oncorhynchus mykiss): implications for conservation
Authors: Keefer Matthew L. , Wertheimer Robert H. , Evans Allen F. , Boggs Charles T. , Peery Christopher A.
Published: February 2009

We used ultrasound imaging and passive integrated transponder (PIT)-tagging programs to assess maturation status and iteroparity patterns in summer-run steelhead (anadromous rainbow trout, Oncorhynchus mykiss ) of the interior Columbia River Basin (Pacific Northwest, USA). Postspawn kelts examined in downstream fish bypass systems at Columbia River and Snake River dams were disproportionately female (>80%) and majorities were of wild origin, unlike prespawn steelhead at these sites. Annual repeat migration estimates varied from 2.9% to 9.0% for kelts tagged at lower Columbia River dams (n = 2542) and from 0.5% to 1.2% for Snake River kelts (n = 3762). Among-site differences reflected greater outmigration distance and additional dam passage hazards for Snake River kelts. There was also strong evidence for condition-dependent mortality, with returns an order of magnitude higher for good- versus poor-condition kelts. Disproportionately more females and wild fish also returned, providing potentially valuable genetic and demographic benefits for the Columbia River’s threatened steelhead populations. Results overall provide baseline data for evaluating kelt mortality mitigation efforts and basic life history information for steelhead conservation planning.
Zooplankton and the total phosphorus – chlorophyll a relationship: hierarchical Bayesian analysis of measurement error
Authors: Kamarainen Amy M. , Rowland Freya E. , Biggs Reinette , Carpenter Stephen R.
Published: February 2009

Zooplankton grazing is important in resolving residual variation around the total phosphorus – chlorophyll a relationship. In empirical studies, zooplankton body size is often a better predictor of residual variation than zooplankton biomass. We investigate whether higher measurement error associated with zooplankton biomass may explain its lower predictive ability. We collected five replicate zooplankton biomass samples in 19 lakes, allowing us to quantify measurement error in volumetric zooplankton biomass with greater precision than in previous studies. A hierarchical Bayesian model was used to assess the predictive ability of volumetric zooplankton biomass and mean individual zooplankton length, corrected for measurement error. We found consistent effects of total zooplankton biomass, but not zooplankton length, on chlorophyll a. This finding does not appear to be related to the higher precision with which total zooplankton biomass was measured in our study, but rather to ecological factors. Interlake variation outweighed the effects of measurement error in estimating the strength of relationships between zooplankton variables and chlorophyll a. Our findings therefore suggest that studies to estimate zooplankton effects on phytoplankton should allocate resources to study a larger range of lakes over different time periods than to process replicate samples to reduce measurement error.
Continental-scale variation in otolith geochemistry of juvenile American shad (Alosa sapidissima)
Authors: Walther Benjamin D. , Thorrold Simon R.
Published: February 2009

We assembled a comprehensive atlas of geochemical signatures in juvenile American shad ( Alosa sapidissima ) to discriminate natal river origins on a large spatial scale and at a high spatial resolution. Otoliths and (or) water samples were collected from 20 major spawning rivers from Florida to Quebec and were analyzed for elemental (Mg:Ca, Mn:Ca, Sr:Ca, and Ba:Ca) and isotope (87Sr:86Sr and δ18O) ratios. We examined correlations between water chemistry and otolith composition for five rivers where both were sampled. While Sr:Ca, Ba:Ca, 87Sr:86Sr, and δ18O values in otoliths reflected those ratios in ambient waters, Mg:Ca and Mn:Ca ratios in otoliths varied independently of water chemistry. Geochemical signatures were highly distinct among rivers, with an average classification accuracy of 93% using only those variables where otolith values were accurately predicted from water chemistry data. The study represents the largest assembled database of otolith signatures from the entire native range of a species, encompassing approximately 2700 km of coastline and 19 degrees of latitude and including all major extant spawning populations. This database will allow reliable estimates of natal origins of migrating ocean-phase American shad from the 2004 annual cohort in the future.
Relating stream physical habitat condition and concordance of biotic productivity across multiple taxa
Authors: Sullivan S. Mažeika P. , Watzin Mary C.
Published: February 2009

To explore the potential of assessments of stream geomorphic condition and habitat quality in evaluating lotic productivity, we investigated concordance of stream biotic productivity (aquatic macroinvertebrates, crayfish, fish, and belted kingfishers ( Ceryle alcyon )) and their physical habitat correlates in 18 streams in the Champlain Valley, Vermont, USA. Pearson correlation analysis indicated significant concordance between macroinvertebrate density and fish biomass (r = 0.76), between the density of macroinvertebrates in the orders Ephemeroptera, Plecoptera, and Trichoptera and fish biomass (r = 0.81), and between fish biomass and kingfisher brood weight (r = 0.54). We used principal component analysis followed by linear regression to investigate relationships between physical habitat condition and biotic productivity and to identify key components of physical habitat condition assessments. Our analysis supported the combined use of geomorphic and habitat assessments as a comprehensive indicator of stream physical habitat condition. We found relationships between habitat assessment scores and productivity measures of all taxa except crayfish, suggesting similar responses to physical condition across trophic levels. Our results encourage the use of additional taxa, in addition to widely used macroinvertebrate metrics, as indicators of the composite effects of physical habitat impairment in stream ecosystems.
A practical framework for selecting among single-species, community-, and ecosystem-based recovery plans
Authors: Poos Mark S. , Mandrak Nicholas E. , McLaughlin Robert L.
Published: February 2009

Science-based approaches for selecting among single-species, community-, and ecosystem-based recovery plans are needed to conserve imperilled species. Selection of recovery plans has often been based on past success rates with other taxa and systems or on economic cost, but less on the ecology of the system in question. We developed a framework for selecting a recovery plan based on the distributions and ecology of imperilled and nonimperilled species across available habitat types and applied it to fishes in the Sydenham River, Ontario, Canada. We first tested whether distributions of fishes were adequately predicted by habitat features hypothesized to limit the distributions of imperilled fishes versus a broader set of habitat features known to predict fish distributions. We then tested whether imperilled species occurred in similar or disparate habitat types. For the Sydenham River, an ecosystem-based recovery plan was deemed most appropriate because imperilled species occur in disparate habitat types. We lastly provide decision criteria to facilitate applications of our framework to the selection of recovery plans for other species and systems.
Stream trees: a statistical method for mapping genetic differences between populations of freshwater organisms to the sections of streams that connect them
Authors: Kalinowski Steven T. , Meeuwig Michael H. , Narum Shawn R. , Taper Mark L.
Published: February 2009

Statistical approaches for studying the spatial distribution of genetic diversity that assume that organisms move through a two-dimensional landscape are not well suited to study populations of freshwater fish. We present a new statistical method for mapping genetic differences among populations of freshwater fish to the sections of streams that connect them. The method is useful for freshwater species that can only disperse through stream corridors and for other species that live in habitats for which there is one, and only one, corridor connecting each pair of populations (e.g., alpine organisms confined to ridge tops). The model is a simple extension of the least-squares method for constructing evolutionary trees. In this model, the genetic distances between populations are modeled as a sum of genetic distances mapped onto landscape features (e.g., stream sections). Analysis of simulated data shows that the method produces useful results with realistic amounts of data. The model was fit to empirical microsatellite data from four metapopulations of freshwater fish and showed an excellent fit in three out of four cases. Software to perform the necessary calculations is available from the authors at www.montana.edu/kalinowski .
Ghost runs: management and status assessment of Pacific salmon (Oncorhynchus spp.) returning to British Columbia’s central and north coasts
Authors: Price M. H.H. , Darimont C. T. , Temple N. F. , MacDuffee S. M.
Published: February 2009

The management of Pacific salmon ( Oncorhynchus spp.) populations, which are spatially distributed across thousands of waterways in coastal British Columbia, Canada, presents considerable challenges to resource managers. We evaluated the efficacy of salmon management by Fisheries and Oceans Canada (DFO) over the past 55 years in two key areas: (i) the achievement of internally generated target escapement levels and (ii) escapement monitoring. We show that less than 4% of monitored streams (n = 7 of 215), which represent a small fraction of all salmon-bearing waterways (n = 2592), have consistently met escapement targets since 1950. During this same period, the number of streams monitored by DFO has simultaneously decreased. Further, current monitoring efforts fall short of encompassing the range of salmon diversity identified within recently designated conservation units. Importantly, we found that this erosion of monitoring effort has been biased towards dropping smaller runs that failed to meet target escapements in the previous decade. We suggest that such increasingly selective monitoring is presenting a progressively more biased evaluation of population health. In addition to fostering a “shifting baseline” syndrome, we conclude that these changes to monitoring can not provide data required for precautionary harvest management under the high exploitation levels that these runs experience.
A mitochondrial multigene approach contributing to the systematics of the brook and river lampreys and the phylogenetic position of Eudontomyzon mariae
Authors: Blank Miriam , Jürss Karl , Bastrop Ralf
Published: February 2009

The evolution of nonparasitic brook lamprey forms and their relationship to the morphological similar parasitic river lampreys are long-standing questions in lamprey research. The present study examines the utility of 11 mitochondrial gene segments (a total of 3800 base pairs) to discriminate the closely related members of the European species pair Lampetra fluviatilis and Lampetra planeri . The intent was to identify fast-evolving genes in the mtDNA that might allow a discrimination of pair members. Therefore, the noncoding regions as the fastest evolving gene segments of animal mtDNA were also included. The results revealed that in all investigated loci, L. fluviatilis and L. planeri were genetically indistinguishable, indicating either a very recent divergence event or ongoing gene flow between both species. The position of the Ukrainian brook lamprey, Eudontomyzon mariae , and the phylogentic relationships within the Lampetrini was inferred from partial cytochrome b by adding available sequences from GenBank to the data set. Eudontomyzon mariae formed a monophyletic cluster with Lampetra aegyptera and the European species pair. A reintegration of E. mariae in the genus Lampetra is therefore recommended.
Toxicity of Trace Metal Mixtures to Alevin Rainbow Trout (Oncorhynchus mykiss) and Larval Fathead Minnow (Pimephales promelas) in Soft, Acidic Water
Authors: Hickie B. E. , Hutchinson N. J. , Dixon D. G. , Hodson P. V.
Published: February 2009

The acute lethality of a fixed-ratio mixture of Al, Mn, Fe, Ni, Zn, Cu, and Pb (75:60:60:12:12:6:6 μg∙L−1 = 1.0 acid lake concentration or ALC, representative of Ontario lakes acidified to pH 5.8) was examined with alevin rainbow trout (Oncorhynchus mykiss) and larval fathead minnow (Pimephales promelas). All testing was done in extremely soft, acidic water (2.5 mg Ca∙L−1; pH 4.6–5.8). For the acid-tolerant trout alevins (144-h LC50 = pH 4.32), median lethal metal mixture levels at pH 5.8 were 5.0 ALC. Toxicity of the mixture increased at lower pHs, with a median lethal threshold of 1.0 ALC at pH 4.9. A mixture of Al, Zn, and Cu was equivalent in toxicity to the full mixture; mixture toxicity was caused by Cu alone at pH 5.8 and by Al alone at pH 4.9. For the acid-sensitive fathead minnow larvae (144-h LC50 = pH 5.54), the mixture of metals typical of lakes acidified to pH 5.8 was lethal (LC50 = 0.84 ALC); again, toxicity was associated with Al, Cu, and Zn. This research implies that Cu could be an important factor contributing to the demise of acid-sensitive fish at pHs above those associated with increased Al solubility and toxicity.
Predation on Ciliates by the Suspension-Feeding Calanoid CopepodAcanthodiaptomus denticornis
Authors: Hartmann Hans J. , Taleb Hassan , Aleya Lotfi , Lair Nicole
Published: February 2009

The effects of prey size, hunger, and algal presence on the predation of the suspension-feeding calanoid copepod Acanthodiaptomus denticornis on the ciliates Tetrahymena corlisii (32 μm mean length), Paramecium aurelia (114 μm), P. caudatum (124 μm), Loxodes sp. [Formula: see text], and Stentor coeruleus[Formula: see text] and the flagellate Astasia longa (14 μm) were evaluated in laboratory experiments. Adult Acanthodiaptomus consumed all species, but not in proportion to their size. At low concentrations (prey < 200 μg C∙L−1), mean clearance rates ranged from 80 mL∙copepod−1∙d−1(for Paramecium) to 13 mL∙copepod−1∙d−1(for Loxodes). Clearance rates declined with increasing concentration of the same prey, as expected. Prey capture and ingestion was determined by cell width and prey escape reactivity. Hunger significantly increased predation rates at high prey levels. The presence of algae enhanced ciliate predation by hungry copepods at low prey levels, but had no other significant effects. Protozoan predation by Acanthodiaptomus generally exceeds its feeding on algae and nanoplankton. Results suggest that ciliates can be a significant part of the diet of some suspension-feeding freshwater copepods in situ, confirming the importance of ciliates as mediators of energy transfer from the microbial loop to higher trophic levels.