bluuebunny/crossref_metadata_2025 huggingface dataset:
Research needs for the management of water quality issues, particularly phosphorus and oxygen concentrations, related to salmonid cage aquaculture in Canadian freshwaters
Authors: Yan N D
Published: April 2005

A growing awareness of the difference between the supply and demand for fish products is fueling rapid growth of an aquaculture industry in Canada, including a freshwater sector, based mainly on the cage farming of rainbow trout. Cage farms can release relatively large loads of organic matter and nutrients to the environment. In consequence, federal and provincial resource management agencies need to develop regulatory instruments that will foster the growth of the industry while ensuring minimal water quality impacts. Such instruments should be science based, but there are currently key gaps in our understanding of the water quality implications of the operations of freshwater cage aquaculture. Here I review the state of science of the water quality implications of cage aquaculture and identify 11 knowledge gaps that currently hamper the development of sound, science-based cage culture management instruments. Perhaps the most important finding of the review is the recognition that, while aquaculture has produced significant increases in lakewater total phosphorus (TP) levels in some situations, classic phosphorus mass balance models may substantially overestimate the contributions of cage farms to TP concentrations in some lakes. Research on this, and perhaps the other knowledge gaps identified in this review, should aid the development of sound management instruments for freshwater cage aquaculture in Canada and elsewhere. Key words: aquaculture, cage culture, water quality issues, phosphorus, BOD, review, research needs, freshwaters.
TESTING FOR EVOLUTIONARY RELATIONSHIP: AN APPLICATION OF MATHEMATICS IN MOLECULAR BIOLOGY
Authors: BARBOUR A. D.
Published: April 2005

The paper illustrates some mathematical problems that are motivated by molecular biological applications and the techniques that are used to address them. The context is that of detecting evolutionary relationship on the basis of molecular sequence data and of measuring its strength. The Stein–Chen method is shown to play a central role in the theoretical analysis of many of the procedures used in practice.
ANALYSIS OF SPACED SEED TECHNIQUE IN SEQUENCE ALIGNMENT
Authors: CHOI KWOK-PUI , ZHANG LOUXIN
Published: April 2005

The novel introduction of spaced seed idea in the filtration step of sequence comparison by Ma, Tromp and Li (2002) has greatly increased the sensitivity of homology search without compromising the speed of search. In this paper, we survey some recent works on spaced seeds with main emphasis on their probabilistic and computational aspects.
ACCELERATING MONTE CARLO MARKOV PROCESSES
Authors: HWANG CHII-RUEY
Published: April 2005

Let π be a probability density proportional to exp - U(x) in S. A convergent Markov process to π(x) may be regarded as a "conceptual" algorithm. Assume that S is a finite set. Let X0,X1,…,Xn,… be a Markov chain with transition matrix P and invariant probability π. Under suitable condition on P, it is known that [Formula: see text] converges to π(f) and the corresponding asymptotic variance v(f, P) depends only on f and P. It is natural to consider criteria vw(P) and va(P), defined respectively by maximizing and averaging v(f, P) over f. Two families of transition matrices are considered. There are four problems to be investigated. Some results and conjectures are given. As for the continuum case, to accelerate the convergence a family of diffusions with drift ∇U(x) + C(x) with div(C(x)exp - U(x)) = 0 is considered.
QUASI-MONTE CARLO METHODS IN COMPUTATIONAL FINANCE
Authors: NIEDERREITER HARALD
Published: April 2005

Quasi-Monte Carlo methods are deterministic versions of Monte Carlo methods, in the sense that the random samples used in the implementation of a Monte Carlo method are replaced by judiciously chosen deterministic points with good distribution properties. They outperform classical Monte Carlo methods in many problems of scientific computing.

This paper discusses applications of quasi-Monte Carlo methods to computational finance, with a special emphasis on the problems of pricing mortgage-backed securities and options. The necessary background on Monte Carlo and quasi-Monte Carlo methods is also provided.
RECENT DEVELOPMENTS ON LOWER TAIL PROBABILITIES FOR GAUSSIAN PROCESSES
Authors: LI WENBO V. , SHAO QI-MAN
Published: April 2005

This paper surveys briefly some recent developments on lower tail probabilities for real valued Gaussian processes. Connections and applications to various problems are discussed. A new and simplified argument is given and it is of independent interest.
Secretory dynamics of leptin in adolescent girls with anorexia nervosa and healthy adolescents
Authors: Misra Madhusmita , Miller Karen K. , Kuo Kelly , Griffin Kathryn , Stewart Victoria , Hunter Emily , Herzog David B. , Klibanski Anne
Published: April 2005

Leptin, an adipocytokine that suppresses appetite and may regulate neuroendocrine pathways, is low in undernourished states like anorexia nervosa (AN). Although leptin exhibits pulsatility, secretory characteristics have not been well described in adolescents and in AN, and the contribution of hypoleptinemia to increased growth hormone (GH) and cortisol in AN has not been explored. We hypothesized that hypoleptinemia in AN reflects decreased basal and pulsatile secretion and may predict increased GH and cortisol levels. Sampling for leptin, GH, cortisol, and ghrelin was performed every 30 min (from 2000 to 0800) in 23 AN and 21 controls 12–18 yr old, and data were analyzed using Cluster and deconvolution methods. Estradiol, thyroid hormones, and body composition were measured. AN girls had lower pulsatile and total leptin secretion than controls ( P < 0.0001) subsequent to decreased burst mass ( P < 0.0001) and basal secretion ( P = 0.02). Nutritional markers predicted leptin characteristics. In a regression model including BMI, body fat, and ghrelin, leptin independently predicted GH burst interval and frequency. Valley leptin contributed to 56% of the variability in GH burst interval, and basal leptin and fasting ghrelin contributed to 42% of variability in burst frequency. Pulsatile leptin independently predicted urine free cortisol/creatinine (15% of variability). Valley leptin predicted cortisol half-life (22% of variability). Leptin predicted estradiol and thyroid hormone levels. In conclusion, hypoleptinemia in AN is subsequent to decreased basal and pulsatile secretion and nutritionally regulated. Leptin predicts GH and cortisol parameters and with ghrelin predicts GH burst frequency. Low leptin and high ghrelin may be dual stimuli for high GH concentrations in undernutrition.
Hemoglobin-Based Oxygen Carrier Distribution Inside Vascular Wall and Arterial Pressure Evolution: Is There a Relationship?
Authors: Smani Y. , Faivre Béatrice , Audonnet-Blaise Sandra , Labrude P. , Vigneron C.
Published: April 2005

The hemoglobin-based oxygen carriers (HBOC), like dextran-benzene-tetracarboxylate-hemoglobin (Dex-BTC-Hb), which are present at high concentrations in plasma disturb arterial pressure and induce hypertension. To study if the increase of mean arterial pressure (MAP) is due to the presence of cell-free hemoglobin (Hb) inside abdominal aortic wall, we followed on a model of 50% isovolemic exchange transfusion (IET) in anesthetized guinea pigs, the kinetic of Dex-BTC-Hb distribution inside abdominal aortic wall and we investigated the relationship between arterial pressure modifications and modified Hb distribution. The administration of Dex-BTC-Hb induced instantaneously an increase of MAP that reached its maximum (53% of hypertension from baseline) at 17 min after the end of the IET and was maintained maximally up to 30 min. A significantly decrease of MAP (45% of hypertension from baseline) was observed after 60 min and the baseline level was recovered at 180 min. The investigation of tissue at 17 min by confocal microscopy showed the presence of free Hb in or upon endothelial cells (EC) in intima and in vasa vasorum. At 180 min, the free Hb was found in or upon EC and inside all abdominal aortic wall meanwhile MAP recovered its basal value. These results suggest for the first time that Hb in intima seems to induce the hypertension observed upon IET but can not sustain it even if Hb stayed present in intima and in abdominal aortic wall.
Serum Procalcitonin Levels Are Elevated in Esophageal Cancer Patients with Postoperative Infectious Complications
Authors: Ito S. , Sato N. , Kojika M. , Yaegashi Y. , Suzuki Y. , Suzuki K. , Endo S.
Published: April 2005

Background: The normal systemic inflammatory response to surgical stimuli often makes early diagnosis of postoperative infections difficult. Purpose: We investigated whether serum procalcitonin (PCT) levels may be a useful marker of bacterial infections in patients after invasive surgery. Subjects and Methods: The subjects were 40 patients who had undergone radical surgery for esophageal carcinoma by a right thoracoabdominal approach. Nine patients were diagnosed to have a postoperative infection during the first 7 days after surgery. Changes in serum PCT levels were compared between the group diagnosed to have postoperative infection (infection group) and the group without infection (noninfection group). Results: The postoperative serum PCT levels were significantly higher in the infection group than in the noninfection group (ANOVA: p < 0.01). Serum PCT peaked on postoperative day (POD) 5 in the infection group (8.7 ± 8.2 ng/ml, mean ± SD) and on POD 1 in the noninfection group (0.5 ± 0.5 ng/ml). No significant differences were found between the two groups in leukocyte count, serum CRP or cytokine levels. The receiver operating characteristics (ROC) curve was constructed for infection identification. The area under the ROC curve for peak postoperative PCT was 0.968, and at a cutoff value of 2.0 ng/ml, the sensitivity was 89% and the specificity was 93%. Conclusions: Serum PCT levels may be useful for the early diagnosis of postoperative infectious complications.
Influence of Gadolinium-Induced Kupffer Cell Blockade on Portal Venous Tolerance in Rat Skin Allograft Transplantation
Authors: Diaz-Peromingo J.A. , Gonzalez-Quintela A.
Published: April 2005

Background: Intraportal injection of donor antigens delays rejection of allografts (portal venous tolerance). The study aimed to investigate the possible influence of prior gadolinium chloride (Gd)-induced Kupffer cell blockade on tolerance to non-vascularized skin allografts induced by means of donor-specific intraportal blood transfusion. Materials and Methods: Wistar rats (n = 10) were used as donors and Sprague-Dawley rats (n = 70) as recipients of a non-vascularized skin graft. Recipients were divided into groups according to the manipulations prior to transplantation, as follows: (1) no manipulation; (2) donor-specific intrajugular blood transfusion; (3) donor-specific intraportal blood transfusion; (4) Gd administration and donor-specific intrajugular blood transfusion; (5) Gd administration and donor-specific intraportal blood transfusion; (6) Gd administration, and (7) intraportal saline infusion. In a first set of experiments, these manipulations were performed once. In a second set of experiments, the same manipulations were performed twice. Skin allograft was performed 7 days after the last manipulation in all groups. Results: Group 3 showed the highest skin graft survival, particularly after repeated blood transfusion. Graft survival in this group was significantly higher than in any other group. Conversely, group 5 showed the lowest graft survival, particularly after repeated blood transfusion. Graft survival in this group was significantly lower than that of groups 1, 2, 3 and 7. Conclusions: In this model of skin allograft transplantation, Gd administration abrogates and can even reverse the tolerogenic effect of repeated donor-specific intraportal blood transfusion.
Thoracic Splenosis Twenty-Nine Years after Traumatic Splenectomy Mimicking Intrathoracic Neoplasm
Authors: Papakonstantinou C. , Christoforidis E. , Vasiliadis K. , Kanellos I. , Zarogoulidis K.
Published: April 2005

Thoracic splenosis refers to a condition of ectopic splenic tissue in the thoracic cavity. It is usually a consequence of splenic tissue seeding in the pleural cavity after thoracoabdominal trauma. A rare case of thoracic splenosis, in a 62-year-old man who had had a traumatic splenectomy due to thoracoabdominal trauma 29 years earlier, is reported. The patient, a heavy smoker, was admitted for evaluation of a left-side thoracic lesion discovered on a plain chest film. Bronchoscopy, CT scan and needle biopsy proved inconclusive for the diagnosis. Exploratory thoracotomy was necessary to establish the diagnosis. During the operation, a thoracic splenosis was confirmed. To date, only 28 cases of thoracic splenosis have been reported in the literature. The purpose of this report is to present a new case of splenosis of the thoracic cavity simulating intrathoracic neoplasm.
Optimization of Prostatic Biopsy: A Prospective Randomized Trial Comparing the Sextant Biopsy with a 10-Core Biopsy
Authors: Paul Roger , Schöler Stefan , van Randenborgh Heiner , Kübler Hubert , Alschibaja Michael , Busch Raymonde , Hartung Rudolf
Published: April 2005

Objective: New prostatic biopsy protocols suggest to increase the core numbers to enhance detection. Additional cores are usually sampled from the lateral part of the p-zone. We direct the sextant biopsy to the most lateral part of the p-zone, therefore we investigated if there is a gain by adding 4 median biopsy cores. Material and Methods: The prospective randomized trial (n = 200) compared our modified sextant biopsy to a 10-core strategy with 2 additional median cores on both sides. Directed biopsies to suspicious areas were allowed in both groups. Morbidity was assessed by a self-administered questionnaire. Results: PC detection was 32% for 6 cores and 40% for 10 cores. Four patients were detected only by median biopsies. Using the binomial distribution table the gain of 4% is statistically significant. There was no statistical difference in morbidity, but a trend towards a higher rate of side effects in the 10-core group. Conclusions: The gain in prostate cancer detection rate by additional median biopsies is low, but statistically significant. There is no difference in morbidity and patient acceptance is high, therefore we favor the 10-core biopsy in our patients.
Preliminary Results of the Effect of Extracorporeal Magnetic Stimulation on Urinary Incontinence after Radical Prostatectomy: A Pilot Study
Authors: Yokoyama Teruhiko , Inoue Miyabi , Fujita Osamu , Nozaki Kunihiro , Nose Hiroyuki , Kumon Hiromi
Published: April 2005

Introduction: Radical prostatectomy is a common procedure for the treatment of clinically localized prostate cancer. However, urinary incontinence is a significant potential source of morbidity following surgery. Extracorporeal magnetic stimulation (ExMS) is a new technology used for pelvic muscle strengthening in the treatment of stress urinary incontinence. We investigated the clinical effects of ExMS on urinary incontinence after retropubic radical prostatectomy. Patients and Methods: Ten patients who had suffered from urinary incontinence for more than 12 months following radical prostatectomy were enrolled in this study. The Neocontrol system was used. Treatment sessions were for 20 min, twice a week for 2 months. The frequency of the pulse field was 10 Hz for 10 min, followed by a second treatment at 50 Hz for 10 min. Objective and subjective measures included voiding diaries, 1-hour pad weight testing, and a quality of life survey at 1, 2, 3, and 6 months after starting the treatment. Urodynamic studies were performed before and after treatment. Results: Three patients became dry (30%), 3 patients improved (30%), and 4 patients showed stationary symptoms (40%). In the 1-hour pad weight testing, the mean pad weight decreased from 25 to 10.3 g, and the quality of life scores had improved from 70.5 to 84.9 2 months after treatment. The frequency of leak episodes per day was reduced from 5.0 times before to 1.9 times after treatment. In the urodynamic study, mean maximum cystometric capacity and Valsalva leak point pressure increased from 197 ± 53.2 to 309 ± 85.3 ml and from 67.3 ± 22.6 to 97.1 ± 22.7 cm H2O after treatment, respectively (p < 0.05). 3 of 6 patients who showed improvement returned to the baseline values within 12 months after treatment and requested maintenance ExMS therapy. No side effects were observed. Conclusions: ExMS therapy offered a new option for urinary incontinence treatment after radical prostatectomy. Further studies are required to determine how long the benefits of treatment last and whether maintenance therapy is necessary.
Short-Term Effects of Arsenic Sulfur in Deficits of Contractile and Relaxant Responses on Urinary Bladder: Pharmacological and Structural Changes
Authors: Gür Serap , Dogan A. Umran , Dogan Meral , Karahan S. Tuna , Can Belgin , Hafez Gaye , Ozgunes Ozan , Kendirci Muammer
Published: April 2005

Introduction: Our goal was to investigate the effects of arsenic sulfur (AsS) on the detrusor smooth muscle reactivity. Material and Methods: AsS (100 ppm µg/g) in drinking water was administered for 2 weeks to two groups of female Wistar rats. The contractile responses of urinary bladders to electrical field stimulation, carbachol, ATP and KCl, and the relaxant responses to ATP, adenosine and isoproterenol were examined. Urinary bladder strips were collected for light microscopic examination. Results: Our results demonstrate that oral inorganic AsS exposure induced enhanced contractile and reduced relaxant responses in rats. We hypothesize that AsS is involved in deficiencies of isolated urinary bladder in rats. Conclusion: These functional and morphological changes may be important as an intermediate link in urinary bladder oncogenesis induced by AsS.
Geburtshilfliche Sonographie – Segen oder Sorgen?
Authors: Winter Raimund , Kimmig Rainer , Fink Daniel
Published: April 2005

Die Einführung der Sonographie hat in der Geburtshilfe zu enormem Fortschritt geführt, doch durch diese Erfolge haben viele Schwangere nun Erwartungen, die nicht immer erfüllt werden können. Pränatal nicht erkannte Fehlbildungen ziehen daher immer häufiger Regressansprüche nach sich. Durch Qualitätssicherung und rechtsverbindliche Aus- und Weiterbildung auf europäischer Ebene könnte die Ärzteschaft dieser Entwicklung aktiv entgegenwirken.
Sinn und Grenzen dergeburtshilflichen Sonographie
Authors: Hackelöer Bernhard-Joachim
Published: April 2005

Die geburtshilfliche Sonographie wird in Deutschland, Österreich und der Schweiz weitgehend als Screening (= Massenuntersuchung) für alle Schwangerschaften durchgeführt. Obwohl die ersten Ziele dieser Screenings bei ihrer Einführung in Deutschland 1981 vor allem die genaue Überprüfung und eventuell Korrektur des Gestationsalters, Erkennung von Mehrlingsschwangerschaften und von Wachstumsretardierung waren, hatten sich die Ziele bis zur Einführung eines 3-Punkte-Screenings 1995 in Richtung Fehlbildungsdiagnostik verschoben. Um eine befriedigende Qualität zu erzeugen, wurde im Sinne einer Arbeitsteilung das Mehrstufenkonzept eingeführt. So können heute sowohl für die 3 Screeninguntersuchungen (10/20/30 Wochen) als auch für die 3 Stufen und die Ultraschallgeräte Inhalte und Qualitäten definiert werden, die helfen können, die teilweise noch unzureichenden Ergebnisse der geburtshilflichen Sonographie zu verbessern. Gleichzeitig soll vor übertriebenen Erwartungen gewarnt werden.
Die Entwicklung der geburtshilflichen Sonographie in der Schweiz
Authors: Zimmermann Roland
Published: April 2005

Ultraschall hat in den letzten 40 Jahren das Fach Geburtshilfe erobert und ist heute ein integraler Bestandteil der Schwangerenvorsorge geworden. Der breite Einsatz als Screeningmethode hat aber auch Kritiker geweckt, die sehr schnell bei Gesundheitspolitikern angesichts knapper Ressourcen im Gesundheitswesen Gehör fanden. In der Schweiz waren 1996 vorübergehend Routineultraschalluntersuchungen nicht (mehr) Kassenpflicht. Unter Druck der Öffentlichkeit hat die Gesundheitsbehörde diesen Entscheid rückgängig gemacht, die Kassenpflicht jedoch an Ärzte mit Ausbildung und Erfahrung, an eine systematische Information der Schwangeren sowie an den Nachweis eines Nutzens geknüpft. Diese Vorschrift hat sich positiv auf die Qualität ausgewirkt. 7 Jahre danach bestehen ein gut funktionierendes Kurswesen, Richtlinien für die Praxis, sowie stichprobenartig Resultate, dass die Qualität in der Schweiz internationalen Vergleichen durchaus standhalten kann. Die Kosten-Nutzen-Analyse zeigt, dass ein Nettonutzen hauptsächlich durch das Erkennen von Fehlbildungen mit anschliessendem Schwangerschaftsabbruch zustande kommt. Da Schwangerschaftsabbrüche ethisch umstritten sind, dürfte die Diskussion um die Kassenpflicht von Ultraschall so schnell nicht zur Ruhe kommen. Eine umfassende vorgängige Information der Schwangeren ist dabei essentiell.
Ausbildung, Ausübung und zunehmende Verrechtlichung des Ultraschalls in Gynäkologie und Geburtshilfe in Österreich
Authors: Brezinka Christoph
Published: April 2005

Während der letzten Jahre hat der oberste Gerichtshof (OGH) in Österreich zwei Ultraschallerkenntnisse veröffentlicht: Die Familie einer an einem Ovarialkarzinom verstorbenen Patientin klagte gegen die Gynäkologin, wonach diese es versäumt hatte, den Tumor im Rahmen einer Routine-Vaginalultraschalluntersuchung 8 Monate vor der Erstdiagnose rechtzeitig zu erkennen. Die Kläger bekamen recht, da das Gericht eine Beweislastumkehr zuliess. Faktisch kommt dieses Urteil einer Einführung des Ovarialkarzinomscreenings mit Ultraschall in Österreich gleich. In einem «wrongful life»-Urteil entschied der OGH, dass die Eltern eines Kindes, das mit Knochenfehlbildungen zur Welt kam, um ihr Recht auf Abtreibung gebracht worden waren, weil die Ärzte im Ultraschall die Knochenfehlbildungen nicht erkannt hatten. Die Auswirkungen dieser beiden Fälle auf die Ultraschallpraxis in Gynäkologie und Geburtshilfe in Österreich werden diskutiert.
Screening auf Chromosomenanomalien im ersten Trimenon
Authors: Krampl Elisabeth
Published: April 2005

Es ist angesichts der heutigen Datenlage offensichtlich, dass im 1. Trimenon ein sehr effizientes Screening auf Chromosomenanomalien durchgeführt werden kann. Prospektive Studien an insgesamt 200 868 Schwangerschaften, darunter 871 Feten mit Trisomie 21, haben gezeigt, dass bei einer Falsch-positiv-Rate von 4,2% eine Messung der Nackentransparenz 76,8% der Feten mit Trisomie 21 identifizieren kann. Kombiniert man die Messung der Nackentransparenz mit der der mütterlichen Serumkonzentrationen von freiem humanem β-Choriongonadotropin und «pregnancy-associated plasma protein A», ist die Entdeckungsrate 87,0% bei einer Falsch-positiv-Rate von 5% (prospektive Studien an insgesamt 44 630 Schwangerschaften mit 215 Feten mit Trisomie 21). Zurzeit werden weitere Hinweiszeichen auf Down-Syndrom im 1. Trimenon untersucht, wie das Fehlen des fetalen Nasenbeins, die Maxilla und das Blutflussmuster im Ductus venosus. Bekannte Hinweiszeichen auf Trisomie 13 und 18, die bereits im 1. Trimenon sichtbar sind, sind Megazystis, Omphalozele, Polydaktylie und Holoprosenzephalie. Die meisten Schwangeren bevorzugen ein Screening im 1. im Vergleich zum 2. Trimenon. Es sollte daher jeder Schwangeren eine entsprechende Untersuchung im 1. Trimenon angeboten werden. Von grundlegender Bedeutung für die Effektivität des Screenings ist, dass die Untersucher entsprechend ausgebildet sind und dass die Ergebnisse der Ultraschalluntersuchungen und der Laboruntersuchungen einer regelmässigen externen Qualitätskontrolle unterzogen werden. In Österreich besteht ein breiter Konsens, nach den Richtlinien der Fetal Medicine Foundation vorzugehen.
Stirbt die Schweiz aus?
Authors: Tönz O.
Published: April 2005

Seit Jahrzehnten unterschreiten in den meisten Ländern Europas die Geburtenziffern den für eine Konstanterhaltung der Bevölkerung notwenigen Sollwert beträchtlich. In der Schweiz beträgt die Gesamtfertilität 1,37 Kinder pro Frau zwischen 15 und 48 Jahren (Soll 2,1); die Schweizerinnen allein – ohne Ausländer – haben den historischen Tiefstwert von 1,21 erreicht. Bei der einheimischen Bevölkerung besteht seit 1998 ein negativer Geburtenüberschuss, d.h. die Aufrechterhaltung der Einwohnerzahl wird nur noch durch Immigration gewährleistet. Bei Weiterbestehen dieser niedrigen Geburtenziffern würde die einheimische Bevölkerung ohne weitere Zuwanderung schon innerhalb von 200 Jahren auf 2% der heutigen Grösse zusammenschrumpfen, also praktisch aussterben. Ursachen dieser demografisch bedenklichen Entwicklung und allenfalls mögliche Gegenmassnahmen werden kurz skizziert.
Sentinel-Lymphonodektomie beim Mammakarzinom – Eigene Erfahrungen
Authors: Rageth Christoph J. , Scholl Beatrix , Sarasin Eliane , Saurenmann Elisabeth
Published: April 2005

Ziel dieser Untersuchung war es, die eigene Lernkurve der Sentinel-Lymphonodektomie mit den Erfahrungen anderer Autoren zu vergleichen. Resultate: Zwischen Juli 1999 und Mai 2004 haben die Autoren 218 Sentinel-Lymphonodektomien, davon 48 in der 24-monatigen Evaluationsphase mit zusätzlicher vollständiger axillärer Lymphonodektomie, durchgeführt. Die Detektionsrate betrug insgesamt 212/218 oder 97,2%, während sie in der Evaluationsphase 38/48 oder 89,6% betrug (Versager waren die Fallnummern 6, 7, 22, 24 und 47). Unter den 48 Fällen in der Evaluationsphase wiesen 24 positive axilläre Lymphknoten auf. Bei 3 dieser Fälle konnte kein Sentinel-Lymphknoten gefunden werden, und bei weiteren 4 Fällen war er im Schnellschnitt falsch negativ. Die falsch negativen Ergebnisse in der Lernphase waren die Fallnummern 2, 10, 23 und 29 (4/21 oder 19%). Ab September 2001 bis Mai 2004 betrug die Detektionsrate über 99% (165/166). Diskussion: Die eigene Erfahrung zeigt, dass die Anfangsphase mit Schwierigkeiten und Unsicherheiten verbunden ist. Die allgemeinen Empfehlungen, während der Lernphase auf die Erfahrung anderer zurückzugreifen und erst nach absolvierter Lernkurve eine alleinige Sentinel-Lymphonodektomie ohne komplettierende Axilladissektion anzubieten, dienen der diagnostischen Sicherheit und können deshalb auch anhand der eigenen Erfahrungen nur unterstützt werden.
Transactivation Properties of Wild-Type and Mutant Androgen Receptors in Transiently Transfected Primary Human Fibroblasts
Authors: Holterhus P.M. , Salzburg J. , Werner R. , Hiort O.
Published: April 2005

Background: Stromal cells play key roles during androgen-mediated male sexual differentiation. Our objective was to establish a transient transfection method for primary human fibroblasts enabling functional characterization of wild-type (wt) and mutant androgen receptor (AR) plasmid constructs, corresponding to partial and complete androgen insensitivity syndrome (PAIS/CAIS). Methods: An AR-negative fibroblast strain (ARD842) was established from the gonads of a CAIS patient. Wt-AR or either mutants L712F (PAIS), R774C or V866M (CAIS) were transfected using a polyamine-based procedure. Alternatively, two AR-positive male foreskin fibroblast strains were investigated. Androgen-induced activation of two co-transfected reporter plasmids ((ARE)2TATA-, MMTV-luciferase) was measured. Results: All three fibroblast strains showed a ligand-dependent rise of luciferase activity after transfection of wt-AR. Mutant plasmids were assessed in AR-negative ARD842 cells. While L712F showed high partial activity, R774C and V866M were nearly inactive. The intrinsic AR of normal foreskin fibroblasts revealed no measurable ligand-inducible reporter gene activity. Conclusions: Polyamine-based transfection of AR plasmids into cultured fibroblasts provides a promising tool for analysis of AR transactivation, thereby considering a stromal cellular background. This is supported by the mutant ARs which showed the expected levels of impaired transactivation with respect to the corresponding AIS phenotypes. The role of the intrinsic AR in normal male human foreskin fibroblasts needs further exploration.
The Estimation of Distributions and the Minimum Relative Entropy Principle
Authors: Mühlenbein Heinz , Höns Robin
Published: April 2005

Estimation of Distribution Algorithms (EDA) have been proposed as an extension of genetic algorithms. In this paper we explain the relationship of EDA to algorithms developed in statistics, artificial intelligence, and statistical physics. The major design issues are discussed within a general interdisciplinary framework. It is shown that maximum entropy approximations play a crucial role. All proposed algorithms try to minimize the Kullback-Leibler divergence KLD between the unknown distribution p(x) and a class q(x) of approximations. However, the Kullback-Leibler divergence is not symmetric. Approximations which suppose that the function to be optimized is additively decomposed (ADF) minimize KLD(q||p), the methods which learn the approximate model from data minimize KLD(p||q). This minimization is identical to maximizing the log-likelihood. In the paper three classes of algorithms are discussed. FDAuses the ADF to compute an approximate factorization of the unknown distribution. The factors are marginal distributions, whose values are computed from samples. The second class is represented by the Bethe-Kikuchi approach which has recently been rediscovered in statistical physics. Here the values of the marginals are computed from a difficult constrained minimization problem. The third class learns the factorization from the data. We analyze our learning algorithm LFDA in detail. It is shown that learning is faced with two problems: first, to detect the important dependencies between the variables, and second, to create an acyclic Bayesian network of bounded clique size.
Population-Based Continuous Optimization, Probabilistic Modelling and Mean Shift
Authors: Gallagher Marcus , Frean Marcus
Published: April 2005

Evolutionary algorithms perform optimization using a population of sample solution points. An interesting development has been to view population-based optimization as the process of evolving an explicit, probabilistic model of the search space. This paper investigates a formal basis for continuous, population-based optimization in terms of a stochastic gradient descent on the Kullback-Leibler divergence between the model probability density and the objective function, represented as an unknown density of assumed form. This leads to an update rule that is related and compared with previous theoretical work, a continuous version of the population-based incremental learning algorithm, and the generalized mean shift clustering framework. Experimental results are presented that demonstrate the dynamics of the new algorithm on a set of simple test problems.
Estimation of Distribution Algorithms with Kikuchi Approximations
Authors: Santana Roberto
Published: April 2005

The question of finding feasible ways for estimating probability distributions is one of the main challenges for Estimation of Distribution Algorithms (EDAs). To estimate the distribution of the selected solutions, EDAs use factorizations constructed according to graphical models. The class of factorizations that can be obtained from these probability models is highly constrained. Expanding the class of factorizations that could be employed for probability approximation is a necessary step for the conception of more robust EDAs. In this paper we introduce a method for learning a more general class of probability factorizations. The method combines a reformulation of a probability approximation procedure known in statistical physics as the Kikuchi approximation of energy, with a novel approach for finding graph decompositions. We present the Markov Network Estimation of Distribution Algorithm (MN-EDA), an EDA that uses Kikuchi approximations to estimate the distribution, and Gibbs Sampling (GS) to generate new points. A systematic empirical evaluation of MN-EDA is done in comparison with different Bayesian network based EDAs. From our experiments we conclude that the algorithm can outperform other EDAs that use traditional methods of probability approximation in the optimization of functions with strong interactions among their variables.
Global Supplier Without a Global Brand Name: A Case Study of Hong Kong's Electronics Industry
Authors: Kwok Hong-Kin , Cheung Lam Richard
Published: April 2005

The production capacity of Hong Kong's electronics manufacturers for certain electronic products has reached the number-one ranking amongst world export suppliers in terms of total quantity, quality and values. Yet, there is an absence of global brand name electronic products in the industry. This paper aims to explore how this development pattern is possible by conducting indepth interview research with 35 managing directors and CEOs from the manufacturer companies, and analyzing secondary data from the Hong Kong government. The research findings indicate that without government support and assistance to overcome the structural difficulties in the production process, and market and product diversification, an individual manufacturer can hardly grow bigger in company size continuously and mobilize large amounts of capital to develop global brand name products. The study also indicates that the role of the government has no effect on the growth of the export sector; however, it influences the industrial organizational structure and industrial specialization pattern.
Institutional Research Productivity, Use of Theory-Driven Research, and Statistical Application in Counseling Psychology
Authors: Kahn Jeffrey H.
Published: April 2005

The author reacts to the three core articles in the Scientific Forum of the May 2005 issue of The Counseling Psychologist about institutional research productivity, the use of theory-driven research, and the application of structural equation modeling to research in counseling psychology. To have a research base that maximizes divergent perspectives, the author argues that the literature should have a diverse group of contributors. Ideas regarding how to build theories, how to improve the precision of theories, and how to test theories in counseling psychology are discussed.
Calls for Multiple Indices Incorporating Multiculturalism in Content Analysis
Authors: Lee Dong-gwi
Published: April 2005

This reaction evaluates three content analyses that investigated separate aspects of research articles published in major counseling psychology journals: (a) institutional research productivity, (b) use of structural equation modeling, and (c) use of theory-driven research. The evaluation focuses on the adequacy of indices used in the content analyses and implications as well as cautions in interpreting the findings. Recommendations are provided with an emphasis on multiculturalism and diversity, the core values of the field of counseling psychology.
Neither Fritz nor Frank
Authors: Zytowski Donald G.
Published: April 2005

The author recounts the ways in which several people have contributed to the development of his career to illustrate the function of relational elements in Super’s stages of career development. A foundation for developing a comprehensive taxonomy of relational components that contribute to an individual’s career development is suggested.
Enhancing Research Productivity in Counseling Psychology
Authors: Betz Nancy E.
Published: April 2005

The present reaction responds to the three research-related core articles in the Scientific Forum of the May 2005 issue of The Counseling Psychologist. I agree that too few of our studies are based on theories or models. Using the nomological network, I suggest how research ideas can more readily be depicted to allow model and theory testing. I comment on some aspects of structural equation modeling and note the usefulness of analyzing how we can improve our use of this increasingly popular method. Finally, I note the striking findings of institutional mobility, both upward and downward, in research productivity and suggest that in-depth analysis of a few of the most dramatic moves might help to explain these findings.
Current Institutional Trends in Research Productivity in Counseling Psychology Journals
Authors: Diegelman Nathan M. , Uffelman Rachel A. , Wagner Kimberly S. , Diegelman Sally A.
Published: April 2005

This study investigated institutional publication activity in counseling psychology journals for the 10-year period from 1993 to 2002. Four journals reported by counseling psychology training directors as prime publication outlets for the field of counseling psychology were used: Journal of Counseling Psychology, The Counseling Psychologist, Journal of Vocational Behavior, and Journal of Counseling and Development. Comparisons with the most recent previous ranking study revealed that institutions in the top 20 remainedfairly stable. However, 13 of the top 40 institutions ranked in this study were not ranked in the previous top 40. Implications for the field are discussed, and suggestions for how to improve publication activity trend analyses are made.
Who Defines What Is Valued in Counseling Psychology? Reply to the Four Reactions
Authors: Uffelman Rachel A. , Wagner Kimberly S. , Diegelman Nathan M. , Diegelman Sally A.
Published: April 2005

The four reviews of the state of the counseling psychology research base in the May 2005 issue of The Counseling Psychologist provide thought-provoking critiques of institutional research productivity. In this rejoinder to these critiques, the authors frame their responses in terms of explaining methodological issues in the original study, discussing the intended use and interpretation of their findings, exploring perceived schisms and values of the field, and offering suggestions for future research and discussion.
Future Directions of Structural Equation Modeling in Counseling Psychology
Authors: Martens Matthew P.
Published: April 2005

The four reactions in the May 2005 issue of The Counseling Psychologist address several considerations regarding the use of structural equation modeling (SEM) in counseling psychology research, including its appropriateness for analyzing one’s data and testing one versus multiple theoretical models. In addition, points that are not mentioned in the author’s original article were also covered, such as evaluating the fit of one’s model, item parceling, and the generalizability of findings. These four reactions are discussed in the context of raising awareness among counseling psychology researchers of considerations associated with the use of SEM.
Mental Models of Poverty in Developing Nations
Authors: Hine Donald W. , Montiel Cristina Jayme , Cooksey Ray W. , Lewko John H.
Published: April 2005

Causal mapping was used to compare poverty activists and non-activists from Canada and the Philippines ( N = 80) in terms of their beliefs about the causes of poverty in developing nations. The causal maps varied as a function of both activist status and country of residence. Activists included more external societal causes in their maps than non-activists, whereas non-activists included more individualistic and internal societal causes. In terms of map structure, Filipino activists included significantly more causal links in their maps than members of the other three groups. A cluster analysis on distance ratios, an index of dissimilarity among the maps, produced three clusters dominated by Filipino non-activists, Canadian non-activists, and Filipino activists, respectively, and a fourth cluster that included a heterogeneous mix of respondents from all four groups. Implications for public education, the effective coordination of antipoverty interventions, and methodological issues related to causal mapping are discussed.
Decision Processes and Use of Decision Aids
Authors: Chu P. C. , Spires Eric E. , Farn C. K. , Sueyoshi Toshiyuki
Published: April 2005

The authors report the results of a controlled laboratory experiment comparing the decision processes of participants from Taiwan and Japan. These two nations have very close geographical, cultural, historical, and economic ties. The results show that decision processes of Taiwanese differed from those of Japanese. Specifically, decision processes adopted by Taiwanese participants were more consistent with compensatory processes than were those adopted by Japanese participants. The authors identify cultural factors that may explain the differences. These results demonstrate the danger of generalizing decision theories across national boundaries, even when the nations are seemingly closely related. The results also indicate that the differences in decision processes among nations cannot easily be characterized as East versus West.
Variation of Individualism and Collectivism within and between 20 Countries
Authors: Green Eva G. T. , Deschamps Jean-Claude , Páez Dario
Published: April 2005

With data from a 20-nation study (N = 2,533), the authors investigated how individual patterns of endorsement of individualist and collectivist attitudes are distributed within and across national contexts. A cluster analysis performed on individual scores of self-reliance (individualist dimension), group-oriented interdependence (collectivist dimension), and competitiveness (individualist or collectivist dimension) yielded a typology of four constrained combinations of these dimensions. Despite the prevalence of a typology group within a given country, variability was observed in all countries. Self-reliant non-competitors and interdependent non-competitors were prevalent among participants from Western nations, whereas self-reliant competitors and interdependent competitors were more common in non-Western countries. These findings emphasize the benefits for cross-cultural research of a typological approach based on combinations of individualist and collectivist dimensions.
The Influence of Conflict Context Characteristics on Conflict Regulation Preferences of Immigrants
Authors: Bierbrauer Günter , Klinger Edgar W.
Published: April 2005

Conflict regulation preferences of male immigrant Turks living in Germany were analyzed. The nature of social relationship between opponents (German or Turk as opponent) and conflict property (tangible vs. intangible) were systematically varied. Furthermore, acculturation preferences were measured both globally and across several domains of life. Results showed that immigrants’ conflict handling preferences varied along social relationship with opponent and along conflict property. Contrary to the assumptions underlying an acculturation perspective, there were no systematic relationships between conflict handling preferences and global or domain-specific acculturation preferences. However, irrespective of their heritage, a majority of the immigrants were familiar with the conflict regulation styles of their host society. This result suggests that behavioral acculturation often results in the acquisition of bicultural competence.
Cross-Cultural Emotion Recognition among Canadian Ethnic Groups
Authors: Beaupré Martin G. , Hess Ursula
Published: April 2005

This study aims to investigate cultural differences in recognition accuracy as well as the in-group advantage hypothesis for emotion recognition among sub-Saharan African, Chinese, and French Canadian individuals living in Canada. The participants viewed expressions of happiness, anger, sadness, fear, disgust, and shame selected from the Montreal Set of Facial Displays of Emotion. These data did not support the in-group advantage hypothesis under the condition of stimulus equivalence. However, both encoder and decoder effects were found. Specifically, French Canadians were more accurate for the decoding of expressions of shame and sadness. Moreover, fear expressions were best recognized when shown by sub-Saharan Africans, suggesting an effect of salience of expressive cues due to morphological features of the face.
Body Image among Ariaal Men from Northern Kenya
Authors: Campbell Benjamin C. , Pope Harrison G. , Filiault Shaun
Published: April 2005

To test attitudes toward male body image in a society with relatively little media exposure, the authors surveyed 53 men, ages 20-35, among the Ariaal, pastoral nomads of northern Kenya. Measures of body image were obtained using a somatomorphic matrix. Height, weight, and percentage of body fat based on bioelectric impedance were also obtained. Results indicate that men exhibit very little discrepancy between what they perceive as the degree of muscularity preferred by women and that of the average man (.21 kg/m2). Comparison with findings from the United States and Western Europe indicates that Ariaal men show significantly less discrepancy between their judgment of women’s preference for muscularity and the muscularity of the average man. These results support a role for media exposure in attitudes about male body image.
Cracking the Nonverbal Code
Authors: Molinsky Andrew L. , Krabbenhoft Mary Anne , Ambady Nalini , Choi Y. Susan
Published: April 2005

The purpose of this set of studies was to assess whether the ability to distinguish between real and fake gestures in a foreign setting is positively associated with cultural adjustment to that setting. To do so, we created an original videotaped measure of gesture recognition accuracy (the GRT). Study 1 ( n = 508) found positive associations between performance on the GRT and length of stay in the foreign setting and between GRT performance and self-reported intercultural communication competence. Study2 ( n = 60) replicated the positive association between GRT performance and self-reported intercultural communication competence. It also found a positive association between GRT performance and external perceptions of intercultural communication competence and motivation as rated by observers native to the new cultural setting. Together, findings from the two studies highlight the importance of gesture recognition in the cultural adaptation process and the potential of the GRT measure as a useful assessment tool.
Erratum to Kashima and Kashima (1998) and Reiteration
Authors: Kashima Emiko S. , Kashima Yoshihisa
Published: April 2005

The relationships between cultural dimensions and the language use involving pronoun drop (whether the subject of a sentence can be dropped when it is a personal pronoun) and the number of second-person singular pronouns (2PS) available in a language (one or multiple) reported by Kashima and Kashima were reexamined by using a new, correct coding for Hindi and Urdu. The reanalysis reconfirmed the major part of our previous results but indicated the need to revise the previous report that the availability of multiple 2PS pronouns was associated with higher Integration, namely, harmonious interpersonal relationships. The new analysis showed that availability of multiple 2PS and Integration were independent of each other.
Destination Branding: Insights and Practices from Destination Management Organizations
Authors: Blain Carmen , Levy Stuart E. , Ritchie J. R. Brent
Published: April 2005

Although the concept of branding has been applied extensively to products and services, tourism destination branding is a relatively recent phenomenon. In particular, destination branding remains narrowly defined to many practitioners in destination management organizations (DMOs) and is not well represented in the tourism literature. Consequently, this study has three goals. First, it attempts to review the conceptual and theoretical underpinnings of branding as conveyed by leading authors in the marketing field. Second, it seeks to refine and enhance the definition of destination branding (acceptable to and understood by tourism destination managers) to more fully represent the complexities of the tourism product. Third, and most importantly, it seeks to improve our understanding of current destination branding practices among DMOs. The findings indicate that although DMO executives generally understand the concept of destination branding, respondents are implementing only selective aspects of this concept, particularly logo design and development.