bluuebunny/crossref_metadata_2025 huggingface dataset:
Limnology and culture‐based fisheries in non‐perennial reservoirs in Sri Lanka
Authors: Jayasinghe U. Asanka D. , Amarasinghe Upali S. , De Silva Sena S.
Published: September 2005

This study was carried out to investigate the possibility of using the limnological characteristics of non‐perennial reservoirs in Sri Lanka for the future management of culture‐based fisheries. Forty‐five reservoirs were randomly selected to study their limnology, out of which 32 were stocked with fish fingerlings of Chinese and Indian carps, tilapia and freshwater prawn at stocking densities ranging from 218–4372 fingerlings ha−1. Of these, 23 reservoirs were harvested at the end of the culture period (6–10 months). Thirteen limnological parameters were measured during the water retention period of each of the 45 reservoirs between November 2001 and January 2004. The mean values of the limnological parameters were used to ordinate the reservoirs through principal component analysis. Ordination showed a productivity gradient among reservoirs where Secchi disc depth, total phosphorus, chlorophyll‐a, inorganic turbidity and organic turbidity were identified as key factors. The total fish yield of culture‐based fisheries was positively correlated to the scores of the first principal component axis. This study reveals that it is possible to classify non‐perennial reservoirs in Sri Lanka based on the above limnological parameters in order to develop culture‐based fisheries and that they could be applicable in comparable water bodies elsewhere in the tropics.
Mutational analysis of the estrogen receptor‐α gene in familial ovarian cancer
Authors: Wu Hong‐Jun , Sekine Masayuki , Kashima Katsunori , Hirai Yasuo , Hatae Masayuki , Kobayashi Iwao , Obata Koshiro , Enomoto Takayuki , Umesaki Naohiko , Ushijima Kimio , Tanaka Kenichi ,   The Japanese Familial Ovarian Cancer Study Group
Published: September 2005

Aim: The genetic region of 6q25 containing the estrogen receptor‐α (ER‐α) gene is lost in a significant number of ovarian tumors. The aim of this study was to identify how inherited variation in the ER‐α gene contributes to susceptibility to familial ovarian cancer.

Methods: DNA obtained from 18 cases of familial ovarian cancer without mutation of the BRCA1 and BRCA2 genes, 20 cases with BRCA1 mutation, 20 cases of sporadic ovarian cancer, and 19 controls were screened for mutations in the coding region of the ER‐α gene using direct sequencing.

Results: Two germline missense variants at codons 307 [GCC(Ala)→TCC(Ser)] and 347 [ACC(Thr)→TCC(Ser)] were detected in two unrelated cases with BRCA1 mutation, but not in all other cases tested. Three polymorphisms in codon 10 [TCT→TCC(Ser)], codon 325 [CCC→CCG(Pro)], and codon 594 [ACA→ACG(Thr)] were identified in this series, and a higher frequency of the allele TCC at codon 10 and a lower frequency of the allele CCG at codon 325 were observed in familial cases without BRCA1 mutation, compared with those in familial cases with BRCA1 mutation, in both the sporadic cases and in the controls.

Conclusions: We could not detect pathogenic mutations of the ER‐α gene in ovarian cancer cases without BRCA1 mutation. However, association analyses of two polymorphisms suggest that the ER‐α gene or a gene located close to the ER‐α locus might be related to susceptibility of familial ovarian cancer without BRCA1 mutation.
Case of uterine cervical carcinosarcoma
Authors: Iida Tetsuji , Yasuda Masanori , Kajiwara Hiroshi , Minematsu Takeo , Osamura R. Yoshiyuki , Itoh Johbu , Inomo Akifumi , Hirasawa Takeshi , Muramatsu Toshinari , Murakami Masaru
Published: September 2005

Carcinosarcoma (CS) is a rare neoplasm that is called a mixed epithelial and mesenchymal malignancy. CS of the uterine cervix is much less common than its counterparts in the uterine corpus. A 61‐year‐old, gravida 2, para 2 woman, who had undergone menopause 16 years prior to the presentation, was diagnosed with CS of the uterine cervix. A semiradical hysterectomy was carried out on the diagnosis of stage Ib1 cervical cancer. The patient underwent whole pelvic 45 Gy radiation as a postoperative additional treatment, but she died from multiple organ failure by metastasis 17 months after the operation. The tumor protruded from the cervix to the vagina and measured 4.5 × 3.0 cm. Histologically, the tumor was characterized as a squamous cell carcinoma and mesenchymal malignancy, represented by osteosarcomatous components. The stroma was largely composed of atypical spindle‐shaped cells, which were immunohistochemically demonstrated to be of epithelial origin. Uterine cervical CS is one of the aggressive malignancies, and squamous cell carcinomas are common epithelial counterparts of cervical CS as well as adenocarcinomas.
Features of patients with vulvar dermatoses in dermatologic and gynecologic practice in Turkey: Is there a need for an interdisciplinary approach?
Authors: Gokdemir Gonca , Baksu Basak , Baksu Alparslan , Davas Inci , Koslu Adem
Published: September 2005

Aim: Vulvar dermatoses are very common problems in women and they are associated with significant morbidity. The aims of the present study were to evaluate the features of patients with vulvar diseases in gynecology and dermatology out‐patient clinics in Turkey, and to determine the need for a multidisciplinary vulvar clinic in this country.

Methods: A total of 310 patients with vulvar problems as their primary complaints were included in the study. There were 144 women from a dermatology clinic and 166 women from a gynecology clinic. The following factors were recorded for all patients: physical examination findings, menarche age, age at first intercourse, education level, marital status, clinical diagnoses and associated gynecologic problems.

Results: There were no significant differences between the two groups when the mean age, menarche age and age at first intercourse were compared (P > 0.05). The number of unmarried women was statistically significantly higher in the dermatology group than in the gynecology group (P < 0.0001). The number of women who graduated from high school and university was also statistically significantly higher in the dermatology group than in the gynecology group (P < 0.01). The frequency of gynecologic problems was statistically significantly higher in the gynecology group than in the dermatology group (P < 0.001); however, dermatologic conditions were the most frequent diagnosis overall (33.54%). Forty patients in the gynecology group were referred to the dermatology clinic.

Conclusions: The approach to patients with vulvar disorders varies from country to country. However, multidisciplinary clinics seem to improve the understanding of vulvar diseases, to make correct diagnoses and to raise patients’ quality of life. The need for a multidisciplinary vulvar clinic should not be ignored by the physicians in Turkey.
Placenta percreta with subsequent uterine rupture at 15 weeks of gestation after two previous cesarean sections
Authors: Honig Arnd , Rieger Lorenz , Thanner Florian , Eck Matthias , Sutterlin Marc , Dietl Johannes
Published: September 2005

A 25‐year‐old gravida 3 para 2 woman was referred to our hospital at 15 weeks’ gestation with an acute abdomen and free fluid in the peritoneal cavity. On admission she was somnolent. She had a history of two cesarean sections. Fetal cardiac activity was detectable by ultrasound preoperatively. Intraoperatively, a lower uterine‐segment rupture was identified in the area of the presumed prior uterine incision. The great blood loss with consecutive coagulopathy required an emergency hysterectomy and multiple blood transfusions. The placenta was located on the lower anterior uterine wall. Intervening decidual cells between placenta and maternal scar tissue were absent in the area of the prior uterine incision. Placental villous tissue deeply invaded and perforated the scar tissue. Histological examination revealed a placenta percreta. Placenta percreta with subsequent uterine rupture is a rare but dramatic complication after previous cesarean section. This should be kept in mind as the rate of elective cesarean sections is rising continuously. Our patient recovered completely.
A reliability‐based data treatment system for actual load history
Authors: XIONG J. J. , SHENOI R. A.
Published: September 2005

This paper seeks to establish an integrated and practical data treatment system for actual load history reliability analysis. A convergence–divergence counting procedure is presented to extract all load cycles from a load history of divergence–convergence waves. The lowest number of load history sampling is established on the basis of the damage‐based prediction criterion. A parameter estimation formula is proposed for hypothesis testing of the load distribution. The examples of its application for the data treatment of actual load history are given. The proposed data treatment system has been shown to have valid and practical characteristics in analysing reliability results.
Short crack growth and fatigue life in austenitic‐ferritic duplex stainless steel
Authors: POLÁK J. , ZEZULKA P.
Published: September 2005

The kinetics of short crack growth has been studied in austenitic‐ferritic 2205 duplex stainless steel. Smooth cylindrical specimens and specimens with shallow notch were subjected to constant plastic strain amplitude loading. The crack growth was studied in notched specimens. The notch area has been mechanically and electrolytically polished to facilitate the observation of crack initiation and growth. The initiated cracks were observed in an SEM (scanning electron microscope). The crack growth was studied using long distance QUESTAR optical microscope equipped with high‐resolution camera. In constant plastic strain amplitude loading the microcracks were initiated and their growth kinetics has been studied. The characteristic features of the crack growth at different plastic strain amplitudes were recorded. Two approaches to analyse the crack growth rates were adopted. The comparison of the prediction of the fatigue life using the plastic‐strain‐dependent crack growth rate was compared with Manson–Coffin law and the relation between parameters of this law and parameters of the short crack growth law were established.
Anesthetic management in two siblings with glutaric aciduria type 1
Authors: HERNÁNDEZ‐PALAZÓN JOAQUÍN , SÁNCHEZ‐RÓDENAS LORENZO , MARTÍNEZ‐LAGE JUAN F. , COLLADO ISABEL CASTAÑO
Published: September 2005

Glutaric aciduria type 1 (GA‐1) is an inborn error of metabolism that results from a deficiency of glutaryl‐CoA dehydrogenase. This disorder mainly manifests in early childhood and most patients with this condition develop a dystonic‐dyskinetic syndrome. We report the anesthetic management of two sisters with GA‐1, aged 30 and 17 months respectively at the time of surgery, who presented with macrocephaly and psychomotor delay. The children required CSF shunting procedures for hydrocephalus and subdural fluid collections, which were performed under total intravenous anesthesia with propofol and remifentanil.
Positioning for the Nuss procedure: avoiding brachial plexus injury
Authors: FOX MARY E. , BENSARD DENIS D. , BRENT ROATEN J. , HENDRICKSON RICHARD J.
Published: September 2005

Background:  In 1987, Nuss developed a minimally invasive technique for the treatment of pectus excavatum. The procedure has had excellent results with minimal complications. Anesthetic concerns include risks of cardiothoracic injuries, dysrythmias, pneumothorax, pleural effusions, and hemorrhage. In addition, we identified a risk of brachial plexus injury that can occur secondary to patient positioning. We report our experience with the Nuss procedure and modified patient positioning.

Methods:  A retrospective chart review was performed on 95 children or adolescents who underwent a Nuss procedure at the Children's Hospital in Denver, CO, USA. The first group of patients (58) was positioned with their arms extended above their heads at a 90° angle at the shoulder. The second group of patients (37) was positioned in an arthroscopy sling in a neutral position utilizing a right angled suspension device attached to the operating room bed.

Results:  In the first group of patients, three of 58 (5.2%) children had transient brachial plexus injuries. To date, in the second group of patients, there have been no brachial plexus injuries using the suspension device.

Conclusions:  We found that patients are at risk of transient brachial plexus injury during the Nuss procedure due to positioning of the arms. A readily available device that permits the extremity to be maintained in a neutral position but also allows intraoperative manipulation during critical aspects of the Nuss procedure eliminates transient brachial plexus palsy.
A 15‐year review of children with Kawasaki's Syndrome having general anesthesia or deep sedation
Authors: MORRISON JOHN E. , ANDERSON MARSHA , CHAN KAK CHEN , PIETRA BIAGIO , ZUK JEANNIE , GNADINGER PHILIP
Published: September 2005

Background:  Children with Kawasaki's syndrome (KS), also known as Kawasaki's disease or ‘mucocutaneous lymph node syndrome’, have approximately 20–25% incidence of developing coronary artery aneurysms (CAA), stenosis or obliteration if not appropriately diagnosed and treated. In addition some children have myocarditis, pericardial effusions and/or cardiac arrhythmias during the acute phase of KS. Even with current treatment protocols, 2–4% will still be at risk of coronary artery pathology and the long‐term implications regarding future coronary artery disease are unknown. Many of these children present for surgical or diagnostic procedures requiring general anesthesia or deep sedation. Only sporadic case reports have been published on the anesthetic experiences of such patients.

Methods:  With Institutional Review approval, we reviewed the medical records of all children with discharge diagnosis of KS from 1985 to 2000 for those receiving general anesthesia or deep sedation. Data abstracted from the medical records included information on any surgical procedures performed any time after onset of KS symptoms, type of anesthetic, perioperative monitoring and presence or absence of operative or perioperative complications.

Results:  A total of 178 children with KS were identified of whom 47 (26.4%) received either general anesthesia (34) or deep sedation (13). There were no deaths; one child developed congestive heart failure in the immediate postoperative period associated with KS myocarditis. Five (15%) of those having general anesthesia initially were either not diagnosed as having KS or had no preoperative cardiac evaluations. None of the children having general anesthesia had ST segment analysis, invasive monitoring or troponin measurements perioperatively.

Conclusions:  The high incidence of serious myocardial complications attributable to KS reported in the pediatric literature is rarely noted in the anesthesia literature. We feel there is a potential for more serious perioperative complications among KS children, although we can only speculate why complications are not more frequently encountered. Anesthetists involved in pediatric services are encouraged to consider KS in their diagnosis of children presenting with febrile illnesses with rashes and to consider the possibility of KS myocardial compromise if they encounter unexpected deterioration perioperatively. Preoperative ultrasound examination and perioperative monitoring (e.g. ST segment analysis and troponin measurements) for myocardial compromise are encouraged if KS is suspected.
Coping in Context: The Role of Stress, Social Support, and Personality in Coping
Authors: DeLongis Anita , Holtzman Susan
Published: September 2005

Abstract
Personality and social relationships play an important role in almost every aspect of stress and coping. Daily process methods are particularly useful in elucidating how these factors might influence both responses to and outcomes of stress. Our work has linked both dimensions of personality, particularly the Big Five, and aspects of social relationships, particularly social support, to the likelihood of engaging in certain coping strategies and the effectiveness or outcomes of these coping strategies. In addition, we have found the effect of personality on coping and stress outcomes to vary by the situational context in which stress occurs. We review findings from our recent daily process studies of stress, coping, and social support. Further, we discuss the costs and benefits of the daily process methodology for addressing these questions, highlighting the clinical utility of findings gleaned with the use of this approach. Finally, we discuss future directions and applications of daily process methods to the study of stress and coping.
On the relevance of mitochondrial fusions for the accumulation of mitochondrial deletion mutants: A modelling study
Authors: Kowald Axel , Jendrach Marina , Pohl Sandra , Bereiter‐Hahn Jürgen , Hammerstein Peter
Published: September 2005

The molecular mechanisms underlying the aging process are still unclear, but the clonal accumulation of mitochondrial deletion mutants is one of the prime candidates. An important question for the mitochondrial theory of aging is to discover how defective organelles might be selected at the expense of wild‐type mitochondria. We propose that mitochondrial fission and fusion events are of critical importance for resolving this apparent contradiction. We show that the occurrence of fusions removes the problems associated with the idea that smaller DNA molecules accumulate because they replicate in a shorter time – the survival of the tiny (SOT) hypothesis. Furthermore, stochastic simulations of mitochondrial replication, mutation and degradation show that two important experimental findings, namely the overall low mosaic pattern of oxidative phosphorylation (OXPHOS) impaired cells in old organisms and the distribution of deletion sizes, can be reproduced and explained by this hypothesis. Finally, we make predictions that can be tested experimentally to further verify our explanation for the age‐related accumulation of mitochondrial deletion mutants.
Economics and Land‐Use Change in Prioritizing Private Land Conservation
Authors: NEWBURN DAVID , REED SARAH , BERCK PETER , MERENLENDER ADINA
Published: September 2005

Abstract:  Incentive‐based strategies such as conservation easements and short‐term management agreements are popular tools for conserving biodiversity on private lands. Billions of dollars are spent by government and private conservation organizations to support land conservation. Although much of conservation biology focuses on reserve design, these methods are often ineffective at optimizing the protection of biological benefits for conservation programs. Our review of the recent literature on protected‐area planning identifies some of the reasons why. We analyzed the site‐selection process according to three important components: biological benefits, land costs, and likelihood of land‐use change. We compared our benefit‐loss‐cost targeting approach with more conventional strategies that omit or inadequately address either land costs or likelihood of land‐use change. Our proposed strategy aims to minimize the expected loss in biological benefit due to future land‐use conversion while considering the full or partial costs of land acquisition. The implicit positive correlation between the likelihood of land‐use conversion and cost of land protection means high‐vulnerability sites with suitable land quality are typically more expensive than low‐vulnerability sites with poor land quality. Therefore, land‐use change and land costs need to be addressed jointly to improve spatial targeting strategies for land conservation. This approach can be extended effectively to land trusts and other institutions implementing conservation programs.
Validity of the SF‐36 Five‐Item Mental Health Index for Major Depression in Functionally Impaired, Community‐Dwelling Elderly Patients
Authors: Friedman Bruce , Heisel Marnin , Delavan Rachel
Published: September 2005

Objectives:To examine criterion and construct validity of the five‐item Mental Health Index (MHI‐5) of the 36‐item Short Form health survey (SF‐36) in relation to the presence of major depression in functionally impaired, community‐dwelling elderly patients and of eight subsamples defined by cognitive functioning, levels of functional impairment, and proxy report versus self‐report.

Design:Cross‐sectional observational.

Setting:Nineteen counties in western New York, West Virginia, and Ohio.

Participants:One thousand four hundred forty‐four functionally impaired, community‐dwelling Medicare beneficiaries aged 65 and older who participated in the Medicare Primary and Consumer‐Directed Care Demonstration.

Measurements:MHI‐5, Mini‐International Neuropsychiatric Interview Major Depressive Episode (MINI‐MDE) module.

Results:The MHI‐5 demonstrated sufficient criterion validity (area under the receiver operating characteristic curve=0.837; sensitivity=78.7% and specificity=72.1% using a cutpoint of 59/60) with respect to the presence of depression for the entire sample. A significant correlation between MHI‐5 scores and presence of major depression as identified using the MINI‐MDE (Spearman correlation=−0.426,P<.001), a strong correlation between the MHI‐5 and the SF‐36 role emotional scale (Spearman correlation=0.522) and a weak correlation with the SF‐36 physical functioning scale (Spearman correlation=0.133) provided evidence for construct validity. Additional evidence is provided by decline in mean MHI‐5 score as level of formal education and number of close friends and relatives decreased. All eight subsamples demonstrated similar criterion and construct validity. A Cronbach alpha of 0.794 demonstrated internal consistency reliability.

Conclusion:This study provides evidence for adequate criterion and construct validity of the MHI‐5 in relation to the presence of major depression among functionally impaired, community‐dwelling elderly Medicare patients.
Mode Switching of Dual Chamber Pacemakers from Activation of a Blanked Flutter Search Algorithm by a Single Atrial Event
Authors: BAROLD S. SERGE , ISRAEL CARSTEN W. , HERWEG BENGT
Published: September 2005

The Medtronic Kappa 700 and 900 pacemaker family offers a dedicated Blanked Flutter Search algorithm specifically designed for the detection of atrial flutter. This report describes 5 cases that demonstrate how the Blanked Flutter Search algorithm can be activated in the absence of atrial tachycardia, atrial flutter, or sinus tachycardia by a single atrial event (AR) detected in the atrial refractory period of the pacemaker provided it is either preceded or followed by a sensed atrial event (AS).
Significance of Inducible Ventricular Flutter‐Fibrillation After Myocardial Infarction
Authors: BREMBILLA‐PERROT BÉATRICE , SUTY‐SELTON CHRISTINE , CLAUDON OLIVIER , DE LA CHAISE ARNAUD TERRIER , LOUIS PIERRE , NIPPERT MARC , POPOVIC BATRIC , BLANGY HUGUES , KHALDI EMAD , BELHAKEM HADJ , BEURRIER DANIEL , HOURIEZ PIERRE
Published: September 2005

Aim: The purpose of this study was to determine the factors associated with the induction of ventricular flutter/fibrillation (VFl/VF)
and its prognostic significance in post‐myocardial infarction.

Methods: Programmed ventricular stimulation was performed after myocardial infarction (MI) for syncope (n = 232) or systematically (n = 755); 230 patients had an induced VFl/VF and were followed during 4 ± 2 years.

Results: VFl/VF was induced in 49/232 patients (21%) with syncope versus 181/755 asymptomatic patients (24%) (NS) and 94/410 patients (23%) with left ventricular ejection fraction (LVEF) <40% versus 136/577 patients (22.5%) with LVEF >40% (NS). Cardiac mortality was 9%; LVEF was 33 ± 15% in patients who died, 43 ± 13% in alive patients (P < 0.004). In patients with LVEF <40%, induced VFl/VF, mortality rate was 31% in those with syncope, 10% in asymptomatic patients (P < 0.001), because of an increase of deaths by heart failure; patients with LVEF >40% with or without syncope had a low mortality (5% and 3%). After linear logistic regression, VFl/VF and LVEF were predictors of total cardiac mortality, but only LVEF <40% predicted sudden death.

Conclusion: Syncope and the level of LVEF did not increase the incidence of VFl/VF induction after MI, but modified the cardiac mortality: induced VF increased total cardiac mortality in patients with syncope and LVEF <40%, but did not increase sudden death. In patients with LVEF >40%, induced VFl/VF has no significance neither in asymptomatic patients nor in those with syncope.
Radiation Doses to Patients and Cardiologists from Permanent Cardiac Pacemaker Implantation Procedures
Authors: TSALAFOUTAS IOANNIS A. , SPANODIMOS STAVROS G. , MANIATIS PETROS N. , FOURNARAKIS GEORGE M. , KOULENTIANOS ELIAS D. , TSIGAS DIMITRIOS L.
Published: September 2005

Background: The purpose of this study was to determine the patient and cardiologist doses during the implantation of permanent cardiac pacemakers under fluoroscopic control.

Methods: For 55 procedures concerning three different types of pacemakers (DDD, VDD, and VVI), the dose‐area product (DAP) meter readings and fluoroscopy times were recorded. From these data, the dose to the operating cardiologist was estimated.

Results: The median values of DAP and fluoroscopy time for all the procedures monitored were 11.4 Gycm2 and 6.6 minute, respectively. For the 22 DDD, 21 VDD, and 12 VVI pacemakers implanted, the respective DAP median values were 14.7, 9.9, and 7.3 Gycm2 and the respective median fluoroscopy times were 8.4, 5, and 2.9 minutes. The median doses to the hands, chest, eyes, and legs of the cardiologist conducting the manipulations were estimated to 0.21, 0.06, 0.03, and 0.11 mGy, respectively, per procedure.

Conclusions: Compared to the existing literature, the median DAP value of this study is almost identical to the 11.2 Gycm2 reported from a sample of 627 patients in 17 different x‐ray rooms, whereas the fluoroscopy times are within the range of values reported by other authors. Concerning the cardiologist exposure, the estimated values indicate that the implantation of pacemakers is a procedure that does not involve a severe risk, especially if it is taken into account that lead aprons and collars are routinely used.
Complications of Implantable Cardioverter Defibrillator Therapy in 440 Consecutive Patients
Authors: ALTER PETER , WALDHANS STEFAN , PLACHTA EVELINE , MOOSDORF RAINER , GRIMM WOLFRAM
Published: September 2005

Background: Although more than 150,000 implantable cardioverter defibrillators (ICDs) are implanted yearly worldwide, only few studies systematically examined complications of ICD therapy in large patient cohorts.

Methods: We prospectively analyzed ICD‐related complications in 440 consecutive patients who underwent first implantation of an ICD system for primary or secondary prevention of sudden cardiac death within the last 10 years at our institution. All study patients received pectoral nonthoracotomy ICD lead systems with the exception of one patient who had an artificial tricuspid valve.

Results: During 46 ± 37 months follow‐up, 136 of 440 patients (31%) experienced at least one complication including implant procedure‐related complications in 43 patients (10%), ICD generator‐related complications in 28 patients (6%), lead‐related complications in 52 patients (12%), and inappropriate shocks in 54 patients (12%). The most serious complications included one perioperative death due to heart failure (0.2%), two ICD system infections necessitating device removal (0.5%) and two perioperative cerebrovascular strokes (0.5%).

Conclusions: We conclude that more than one quarter of ICD patients experience complications during a mean follow‐up of almost 4 years, although serious complications such as intraoperative death or ICD system infections are rare in patients with nonthoracotomy ICD systems. Recognition of these complications is the prerequisite for advances in ICD technology and management strategies to avoid their recurrence.
Familial Atrial Standstill in Association with Dilated Cardiomyopathy
Authors: FAZELIFAR AMIR FARJAM , ARYA ARASH , HAGHJOO MAJID , SADR‐AMELI MOHAMMAD ALI
Published: September 2005

Atrial standstill is an extremely uncommon arrhythmia that rarely appears to be familial and genetically determined. Atrial standstill has been associated with several conditions including, but not restricted to, congenital heart disease, valvular heart disease, conduction disturbances, Brugada syndrome, myocardial infarction, and amyloidosis. Only a few cases of familial clustering of atrial standstill have been reported so far. This report represents a family with atrial standstill associated with syncope, dilated cardiomyopathy, and sudden cardiac death.
A Rare Case of “Runaway” Pacemaker in a Modern CPU‐Controlled Pacemaker
Authors: MAKARYUS AMGAD N. , PATRICK CAROL , MACCARO PAUL
Published: September 2005

“Runaway” pacemaker is a rare entity that occurs when a malfunctioning artificial cardiac pacemaker abruptly accelerates its pacing rate above the set upper rate limit. This can result in life‐threatening dysrhythmia. Runaway pacemaker used to occur more frequently in older model pacemakers, but now with newer pacemaker generators, runaway pacemaker is a rare entity. We report the case of a runaway pacemaker in a modern CPU‐controlled pacemaker in a 79‐year‐old man presenting with lightheadedness and review the literature regarding this rare entity.
Long‐Term Performance of Screw‐In Atrial Pacing Leads: A Randomized Comparison of J‐Shaped and Straight Leads
Authors: LURIA DAVID , BAR‐LEV DAVID , GUREVITZ OSNAT , GRANIT HAVA , ROTSTEIN ZEEV , ELDAR MICHAEL , GLIKSON MICHAEL
Published: September 2005

Objective: In this prospective, randomized, control study we compared performance of J‐shaped (JL) and straight atrial leads (SL) with active (screw‐in) fixation mechanism, over a 5‐year follow‐up period.

Subjects and Methods: A total of 208 consecutive patients were randomized for implantation with a Medtronic 4568 JL model (n = 103) versus a Medtronic 4068 SL model (n = 105), and all lead‐related measurements and complications were recorded.

Results: Lead‐related complications occurred in JL and SL with similar frequency (6% and 9%, respectively, P = 0.45). Lead dislodgment occurred in 8 (7.8%) cases in SL versus none in JL (P = 0.004). Lead malfunction and excessive pacing thresholds without macrodislodgment occurred more frequently in JL (11; 10.7%) than in SL (4; 3.8%), P = 0.055. Lead material failure (insulation break) occurred only once in SL at the 5‐year checkup. Most complications occurred during the first year after implantation. Other events occurred in both leads with similar frequency and included: death in 39 and 35, loss of follow‐up in 8 and 6, and development of atrial fibrillation in 9 and 15 patients, respectively. Of those who completed follow‐up, lead impedance and pacing threshold increased significantly in both groups. P wave decreased in SL but not in JL.

Conclusion: More dislocations occurred in SL, but were counterbalanced by more lead malfunctions and excessive pacing thresholds in the JL group. Both leads demonstrated minor deterioration in electrical measurements during follow‐up, with only 1 case of lead material failure in SL. Overall, both groups demonstrated favorable lead performance throughout follow‐up.
Efficacy and Safety of Ibutilide for Cardioversion of Atrial Flutter and Fibrillation in Patients Receiving Amiodarone or Propafenone
Authors: FRAGAKIS NIKOLAOS , PAPADOPOULOS NIKOLAOS , PAPANASTASIOU SOULTANA , KOZIRAKIS MILTIADIS , MALIGKOS GEORGE , TSARITSANIOTIS EVANGELOS , KATSARIS GEORGE
Published: September 2005

Aim: The effectiveness and safety of ibutilide (IB) use in patients receiving amiodarone or propafenone for atrial flutter (AFL) and atrial fibrillation (AF) were compared to IB alone.

Methods and Results: In 104 consecutive patients with AF (65%) or AFL (35%), receiving amiodarone (n = 46), propafenone (n = 30), or no specific antiarrhythmic drug (n = 28), IB was given for cardioversion. Fifteen patients in amiodarone group were loaded with 1.2 g intravenously before IB administration.

The mean duration of arrhythmia episode was 23 ± 65 days, while 85% of patients had structural heart disease. The left ventricle ejection fraction was 57 ± 10% and the left atrium size was 4.2 ± 0.6 cm. The conversion efficacy did not differ among groups (62% for amiodarone vs 55% for propafenone vs 64% for IB alone). The QTc intervals were significantly prolonged, at 10 minutes and 30 minutes after IB administration, in amiodarone group (from 449 ± 88 to 496 ± 92 ms, 508 ± 52 ms; P = 0.001) and in the group where IB was used alone (from 434 ± 45 to 517 ± 74 ms, 492 ± 65 ms; P < 0.001), while it remained unchanged in propafenone group (from 464 ± 52 to 471 ± 80 ms, 489 ± 93 ms; P = 0.536). The only predictor of conversion was the presence of AFL (P = 0.009). Five patients developed ventricular tachycardias after IB administration (two in propafenone, one in amiodarone, and two in IB group).

Conclusions: The use of IB in patients receiving amiodarone or propafenone for AFL or AF is equally effective and safe as the use of IB alone. The presence of AFL is the stronger predictor factor for cardioversion.
Pulmonary Vein Morphology Before and After Segmental Isolation in Patients with Atrial Fibrillation
Authors: UEDA MAREHIKO , TADA HIROSHI , KUROSAKI KENJI , ITOI KAZUHIRO , KOYAMA KEIKO , NAITO SHIGETO , ITO SACHIKO , KOMURO ISSEI , OSHIMA SHIGERU , TANIGUCHI KOICHI
Published: September 2005

Background: The morphology of the pulmonary veins (PVs) before and after segmental isolation of the PVs has not been sufficiently characterized.

Methods and Results: Multi‐slice computed tomography was performed before and 3 ± 1 months after ablation in 30 patients with atrial fibrillation who underwent PV isolation. Before ablation, PV narrowing (≥25% luminal reduction) was found in nine (8%) PVs. After ablation, de novo PV narrowing was found in 24 PVs (26%) and was detected only in the supero‐inferior direction in 14 PVs (58%). The diameter reduction inside the PVs after ablation was greater in the supero‐inferior direction (14 ± 12%) than in the antero‐posterior direction (9 ± 13%; P < 0.0001). In the ablated PVs, the PV trunk was shorter than before ablation (P < 0.0001). The reduction in the diameters of both the PV ostium and the ablation site in the ablated PVs, as well as the diameter of the PV ostium in the nonablated PVs, correlated with the decrease in the left atrial diameter. Shortening of the PV trunk correlated with the severity of PV narrowing, but it was not related to the percent diameter reduction of the left atrium. PV narrowing before or after ablation did not result in any clinical consequences.

Conclusions: PV narrowing is present in about 10% of PVs before ablation. Asymmetric luminal reduction and longitudinal shrinkage of the PV trunk occur after ablation. Reverse remodeling of the PV and contraction of the PV wall may contribute to the reduction in the PV diameter. PV morphology should be assessed with multi‐directional views to avoid missing heterogeneous legions.
Do We Need a Reflex Tachycardia to Stand Up?
Authors: FORTRAT JACQUES‐OLIVIER , LEMARIE CATHERINE , BELLARD ELISABETH , VICTOR JACQUES
Published: September 2005

Background: Sophisticated atrio‐ventricular pacing models are designed to integrate the pacemaker into cardiovascular autonomic control to react appropriately to the cardiovascular demands. Such an approach might be beneficial for patients with vasovagal responses to counterbalance the upright fall in arterial blood pressure by a pacing rate increase. We hypothesized that this approach would improve the cardiovascular response to standing in comparison with a regular pacing mode.

Methods: Two 5‐minute tilt tests were performed in a random order in 5 patients with a pacemaker (CLS‐INOS2) for sinus node disease and atrio‐ventricular block. One tilt test was performed in fixed pacing rate (DDD), the other one was performed in close loop stimulation (CLS), which allowed an upright rate‐rise pacing. Heart rate, systolic blood pressure, and cardiac output (modelflow) were recorded on a beat‐by‐beat basis.

Results: Changes of systolic blood pressure and cardiac output in response to upright posture were not significantly different between DDD and CLS modes (2.7 ± 13.2 vs 10.1 ± 12.9 mmHg and −0.8 ± 0.3 vs −1.1 ± 0.4 L/min, respectively).
But upright posture led to a tachycardia of more than 30 bpm in 3 patients in CLS mode and to a fall in systolic blood pressure greater than 20 mmHg in 3 patients in CLS mode and only in one patient in DDD mode.

Conclusion: Systolic blood pressure and cardiac output are not improved by the upright tachycardia and upright blood pressure response is actually worsened when an upright rate‐rise pacing is used. Thus, it appears that tachycardia alone cannot compensate for an upright fall in blood pressure.
Toughening of a Cordierite Glass–Ceramic by Compressive Surface Layers
Authors: Cook Robert F.
Published: September 2005

An indentation fracture mechanics analysis is developed to characterize the toughening effects of a compressive surface layer in brittle materials. The analysis is used to describe the enhanced toughness of cordierite glass–ceramic laminate composites, in which thermal‐expansion mismatch effects induced uniform stress in the exterior layers of the symmetric exterior:interior:exterior structures. Interpretation of indentation crack length and inert strength tests via the analysis shows that cracks can be viewed as experiencing discrete regions of decreasing stabilization on propagation from small cracks and complete containment within the compressive layer to large cracks and partial extension into the compensating tensile interior. The observations are described using a stress‐intensity factor for circular cracks in linear stress fields that includes different base and surface values for extended cracks. Deconvolution of inert strength data for the model cordierite system studied suggested an increase in toughness from 1.4 MPa·m1/2 for the base material to a peak of about 5 MPa·m1/2 for a 1:18:1 composite structure, with attendant increases in strength and flaw tolerance.
Phase Equilibrium Investigations on Na–K–(β+β″)‐Alumina
Authors: Yang Jianhua , Näfe Helfried , Aldinger Fritz , Yan Dongsheng
Published: September 2005

The activities of Na2O and K2O dissolved in mixed‐alkali Na–K–(β+β″)‐Al2O3 (NKBA) have been determined by using yttria stabilized zirconia (YSZ) as a solid electrolyte in the following galvanic cells:

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The approach enables to verify in situ the establishment and maintenance of the β/β″‐equilibrium, and to characterize it as a function of the phase composition of NKBA. The results can be expressed as follows:

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Compressive Surface Layer to Avoid Edge Cracking in Laminar Ceramic Composite
Authors: Kiefer Thomas , Moon Haksung , Lange Fred F.
Published: September 2005

Previous work has shown that layers within ceramic laminates that contain biaxial compressive stresses will also contain tensile stresses where the layer intercepts the surface. It has also been shown that when the thickness of the layer exceeds a critical value, the tensile stresses at and near the surface can produce a centerline crack that extends along the surface to a depth corresponding to the thickness of the compressive layer. The current work explores the concept of preventing the occurrence of surface cracks with a thin layer of material that places the entire external surface in compression. A recent finite element analysis by Monkowski and Beltz showed that when the external surface layer material was identical to the compressive layers, the tensile stresses at the surface could be reduced to zero when the thickness of the surface layer was 0.6 of the thickness of the compressive layer. In addition, they determined the stress intensity factor function for a surface crack and showed that surface cracking could be avoided when the thickness of the surface layer was ≥0.25 times the thickness of the compressive layer. The experimental results presented here show that a thin compressive layer will prevent surface cracks from forming in the compressive layers; the results also appear to confirm the predictions of Monkowski and Beltz.
Catalytic Performance of Metal Nanoparticles Supported by Ceramic Composite Produced by Partial Reduction of Solid Solution with Dopant
Authors: Fukasawa T. , Suetsuna T. , Harada K. , Suenaga S.
Published: September 2005

A composite with well‐dispersed metal nanoparticles at a ceramic surface was produced by partial reduction of solid solution. It was found that a small amount of dopant, such as Al2O3, Cr2O3, or Sc2O3, accelerated the precipitation of the metal nanoparticles during the reduction. Catalytic performance of the composite for methanol reforming was evaluated. In the Ni‐based catalysts, the dopant decreased the CO production by promoting a methanation reaction, while in the Co‐based catalysts, the dopant did it by inducing a water–gas shift reaction. Co/MgO with Sc2O3 doping showed the most preferable reforming performance, high H2 production, and CO2 selectivity.
Effect of Sintering on Mechanical Properties of Plasma‐Sprayed Zirconia‐Based Thermal Barrier Coatings
Authors: Choi Sung R. , Zhu Dongming , Miller Robert A.
Published: September 2005

The effect of sintering on the mechanical properties of free‐standing, plasma‐sprayed ZrO2–8 wt% Y2O3 thick thermal barrier coatings (TBCs) was determined after annealing at 1316°C in air. Mechanical properties of the TBCs, including flexure strength, modes I and II fracture toughnesses, constitutive relations, elastic modulus, and microhardness, were determined at ambient temperature as a function of annealing time ranging from 0 to 500 h. In addition, some physical properties such as density and phase stability were also determined. Mechanical and physical properties increased significantly in 5–100 h and then reached a plateau above 100 h. An exception to this was the monoclinic phase that increased monotonically without forming a plateau. Annealing resulted in healing of microcracks and pores, and in grain growth, accompanying densification of the TBC's body because of the sintering effect. However, an inevitable adverse effect also occurred such that the desired lower thermal conductivity and good strain‐tolerant capability, which makes the TBCs unique in thermal barrier applications, were degraded upon annealing. A phenomenological model was proposed to assess and quantify all the property variables in response to annealing in a normalized scheme.
Tantalum Penta‐Glycolate Sol as a Precursor of Strontium Bismuth Tantalate Ferroelectric Thin Films
Authors: Calzada M. L. , González A.
Published: September 2005

A sol–gel synthesis method based on the diol route is reported here for the fabrication of strontium bismuth tantalate (SBT, SrBi2Ta2O9) ferroelectric thin films. A tantalum penta‐glycolate (TPG)‐based sol is synthesized, which is air stable and has low toxicity. The structure of the TPG compound is studied by nuclear magnetic resonance (NMR) spectrometry, and the results show that TPG contains a tantalum cation bonded to five diol groups. The molecular association of the TPG derivatives in the sol, through the terminal hydroxyl groups of the diol ligands, is responsible for its transformation into a gel. Other metal compounds can be easily added to the TPG‐based sols for the preparation of air‐stable and precipitate‐free multicomponent solutions. These solutions are precursors of complex oxide materials. In this paper, SBT thin films have been prepared by this sol–gel method. These films develop a layered perovskite structure after crystallization. The films have a remanent polarization of Pr∼10 μC/cm2, a coercive field of Ec∼65 kV/cm, and are fatigue free up to ∼1010 cycles.
Effect of Unfired Tape Porosity on Surface Film Formation by Dip Coating
Authors: Pontin Michael G. , Lange Fred F. , Sánchez‐Herencia Antonio J. , Moreno Rodrigo
Published: September 2005

Thin ceramic layers have been fabricated by dipping green tapes of alumina, formed by the doctor‐blade casting method, into aqueous slurries containing mixtures of alumina and either unstabilized zirconia (MZ–ZrO2) or mullite. It was observed that the formation of a thin layer on the surface of the tape is governed by both liquid entrainment and slip‐casting mechanisms, and was accelerated by increasing the withdrawal rate, immersion time, or volume fraction of solids in the slurry used for dip coating. By modifying these parameters, layers as thin as 2 μm and as thick as 108 μm were easily formed. Layer formation was found to be strongly influenced by the structure of the tape surface. Layers formed on the top surface of the tape were found to be as much as 48% thicker than those formed on the bottom surface. This difference appears to be related to the smaller amount of porosity on the bottom surface of the tape. Evidence suggests that the polymer binder, used for doctor‐blade casting, concentrated on the bottom of the tape as evaporation occurred from the top surface. The lower porosity on the bottom reduced the casting rate during dip coating and produced significantly thinner layers, relative to the top surface.
Novel Fabrication of High‐Quality ZrO2 Ceramic Thin Films from Aqueous Solution
Authors: Kuratani Kentaro , Uemura Masayasu , Mizuhata Minoru , Kajinami Akihiko , Deki Shigehito
Published: September 2005

We report on the direct deposition of high‐quality ZrO2 thin films on various kinds of substrates by the liquid phase deposition method. After reaction for 24 h, thin films formed on various kinds of substrates, and the obtained thin film was comprised of densely packed nano‐sized particles. The film annealed at 500°C showed a tetragonal phase at room temperature and this phenomenon has been discussed from the viewpoint of crystallite size effect. The result of optical transmittance measurement revealed that high transparency, more than 70% transmittance, has been achieved for the film after annealing at 900°C.
Formation and Densification Behavior of Magnesium Aluminate Spinel: The Influence of CaO and Moisture in the Precursors
Authors: Ganesh Ibram , Teja Kolli Archana , Thiyagarajan Natarajan , Johnson Roy , Reddy Benjaram Mahipal
Published: September 2005

Different grades of stoichiometric and non‐stoichiometric dense magnesium aluminate spinel (MgAl2O4) grains were prepared by a conventional double‐stage firing process using two types of alumina and four types of magnesia raw materials. The MgAl2O4spinel formation was found to be highly influenced by CaO and moisture present in the precursor oxides as confirmed by thermogravimetry (TG), differential thermal analysis (DTA), and X‐ray diffraction (XRD) techniques. The Fourier transform‐infrared spectroscopy (FTIR) study of the precursor oxides revealed the presence of moisture. Influence of alumina and magnesia composition on the densification behavior of MgAl2O4spinels was assessed by characterizing bulk density (BD), apparent porosity (AP), water absorption (WA) capacity, and the microstructures of the stoichiometric, the magnesia‐rich, and the alumina‐rich spinels sintered at 1650°C for 1 h. Sintering studies indicate that to obtain dense stoichiometric spinel grains with >3.35 g/mL BD, <2.0% AP, and <0.5% WA, the spinel powder should possess a median particle size of <2 μm, CaO content of >0.9%, compact (green) density of >1.95 g/mL, and spinel content of >90%. Among various spinels synthesized, the magnesia‐rich spinels exhibited superior properties in terms of high BD, low percentage of AP, and low WA capacity, whereas alumina‐rich spinels showed inferior properties. Stoichiometric spinels exhibited an average grain size of 10 μm whereas alumina‐rich spinels with 90% alumina had an average grain size of 20 μm. The increase in holding time at higher temperatures enhanced the sintering properties of the spinels, particularly the magnesia‐rich spinels. Further, raw mixtures having >0.9% CaO exhibited better sintered properties as compared with others.