bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF GRAIN SIZE ON THE FERROELECTRIC PROPERTIES OF Bi3.25La0.75Ti3O12 Thin Films
Authors: KIM KYOUNG-TAE , KIM CHANG-IL , KANG DONG-HEE , SHIM IL-WUN
Published: December 2002

The Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin films were prepared by metalorganic decomposition method. The effect of grain size on the ferroelectric properties during crystallization were investigated by x-ray diffraction and field emission scanning electron microscope. The grain size and the roughness of BLT films increase with increasing of drying temperature. The leakage current densities of the BLT thin film with large grains are higher than that with small grains. The remanent polarization of BLT increase with increasing grain size. As compared BLT with small grain size, the BLT film with larger grain size shows better fatigue properties. This may be explained that small grained films shows more degradation of switching charge than large grained films.
MEASUREMENT OF ELECTRICAL ACTIVATION ENERGY IN BLACK CVD DIAMOND USING IMPEDANCE SPECTROSCOPY
Authors: YE HAITAO , WILLIAMS OLIVER A. , JACKMAN RICHARD B.
Published: December 2002

Dc current-voltage (I-V) measurement, Hall measurement, Deep-level transient-spectroscopy (DLTS), and flatband capacitance measurement have been used to investigate electrical activation energies in diamond. However, the deviations still exist in the published activation energies obtained by these methods. In this paper, we report the first measurement of impedance on free-standing diamond films from 0.1Hz to 10MHz up to 300°C. A wide range of CVD materials have been investigated, but here we concentrate on 'black' diamond grown by MWPECVD. The Cole-Cole (Z′ via Z″) plots are well fitted to a RC parallel circuit model and the equivalent Resistance and Capacitance for the diamond films have been estimated using the Zview curve fitting. The results show only one single semicircle response at each temperature measured. It was found that the resistance decreases from 62 MΩ at room temperature to 4 KΩ at 300°C, with an activation energy around 0.15eV. The equivalent capacitance is maintained at the level of 102 pF up to 300°C suggesting that the diamond grain boundaries are dominating the conduction. At 400°C, the impedance at low frequencies shows a linear tail, which can be explained that the AC polarization of diamond/Au interface occurs.
EVIDENCE OF TWO-DIMENSIONAL GAUGE-GLASS BEHAVIOR NEAR THE COHERENCE TRANSITION OF DyBa2Cu3O7-δ ULTRA-THIN FILMS
Authors: ROA-ROJAS J.
Published: December 2002

Systematic measurements of electrical magnetoconductivity near the coherence transition of granular DyBa 2 Cu 3O7-δ ultra-thin films are reported. Two type of experiments were performed: diverse current densities up to 80 A/cm 2 were applied in the absence of magnetic field H and magnetic fields ranging from 0 to 2.5 kOe were applied perpendicular to the structural Cu–O planes to study the phase-glass transition. Close to the zero resistance state, the measurements reveal the occurrence of a coherence transition, where the phases of the order parameter in individual grains become long-range ordered. The critical temperature, T c0 (H), for this transition is close to the point where the resistivity vanishes. A strong enlargement of the fluctuation interval preceding the coherence transition is caused by the applied magnetic field. The critical conductivity behavior for the coherence transition is interpreted within a 3D-XY model where disorder and frustration are relevant. It was evidenced that close to the coherence transition, the correlation length scales as a power law of temperature with a temperature-dependent critical exponent ν. In the presence of external magnetic fields, the corresponding value of ν is consistent with the 2D-gauge-glass model. In the absence of applied magnetic fields, the value of ν is not the same as for the 2D-phase-glass model. A scaling into the framework of the vortex-glass theory shows that the chiral- and gauge-glass behaviors are in different dynamic universality classes.
American Society of Clinical Oncology 2001 Presidential Initiative: Impact of Regulatory Burdens on Quality Cancer Care
Authors: Einhorn Lawrence H. , Levinson Jenifer , Li Susan , Lamar Laurie , Kamin Deborah , Mendelson Dan
Published: December 2002

PURPOSE: This study was conducted as part of the American Society of Clinical Oncology (ASCO) 2001 Presidential Initiative to assess the administrative burden of payer documentation requirements and their impact on oncology practice.

METHODS: The study consisted of a physician questionnaire and an activity log. Site visits were conducted to support survey data. Analysis included 2,493 questionnaires and 1,115 activity logs; data were also collected from site visits to 10 oncology practices.

RESULTS: Increased documentation was the greatest concern among respondents, greater even than the stress of dealing with death and dying. More than 97% of survey respondents reported an increase in documentation (averaging 1.4 h/d) and 77% reported an increase in work hours because of documentation in the past 5 years. As a result, more than 40% of respondents reported decreases in key aspects of patient care and decreases in teaching (48%) and research (39%). Site visit data demonstrate similar trends.

CONCLUSION: It is critical to find ways to decrease physician burden without decreasing the ability to prevent fraud and abuse. Reforms include provisions in a recently passed bill in the United States House of Representatives to streamline Medicare regulation and increase physician education. To address oncology-specific concerns, changes also should be made to supervision requirements for residents and fellows and evaluation and management documentation for oncology follow-up visits.
Randomized Adjuvant Trial of Tamoxifen and Goserelin Versus Cyclophosphamide, Methotrexate, and Fluorouracil: Evidence for the Superiority of Treatment With Endocrine Blockade in Premenopausal Patients With Hormone-Responsive Breast Cancer—Austrian Breast and Colorectal Cancer Study Group Trial 5
Authors: Jakesz Raimund , Hausmaninger Hubert , Kubista Ernst , Gnant Michael , Menzel Christian , Bauernhofer Thomas , Seifert Michael , Haider Karin , Mlineritsch Brigitte , Steindorfer Peter , Kwasny Werner , Fridrik Michael , Steger Guenther , Wette Viktor , Samonigg Hellmut
Published: December 2002

PURPOSE: Effective adjuvant treatment modalities in premenopausal breast cancer patients today include chemotherapy, ovariectomy, and tamoxifen administration. The purpose of Austrian Breast and Colorectal Cancer Study Group Trial 5 was to compare the efficacy of a combination endocrine treatment with standard chemotherapy.

PATIENTS AND METHODS: Assessable trial subjects (N = 1,034) presenting with hormone-responsive disease were randomized to receive either 3 years of goserelin plus 5 years of tamoxifen or six cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF). Stratification criteria included tumor stage and grade, number of involved nodes, type of surgery, and steroid hormone receptor content. Relapse-free survival (RFS) was defined as time from randomization to first relapse, local recurrence, or contralateral incidence, and overall survival (OS) as time to date of death.

RESULTS: With a 60-month median follow-up, 17.2% of patients in the endocrine group and 20.8% undergoing chemotherapy developed relapses. Local recurrences emerged in 4.7% and 8.0%, respectively. RFS and local recurrence-free survival differed significantly in favor of endocrine therapy (P = .037 and P = .015), with a similar trend observed in OS (P = .195).

CONCLUSION: Overall, our data suggest that the goserelin-tamoxifen combination is significantly more effective than CMF in the adjuvant treatment of premenopausal patients with stage I and II breast cancer.
Transplantation of Peripheral Blood Stem Cells as Compared With Bone Marrow From HLA-Identical Siblings in Adult Patients With Acute Myeloid Leukemia and Acute Lymphoblastic Leukemia
Authors: Ringdén O. , Labopin M. , Bacigalupo A. , Arcese W. , Schaefer U.W. , Willemze R. , Koc H. , Bunjes D. , Gluckman E. , Rocha V. , Schattenberg A. , Frassoni F.
Published: December 2002

PURPOSE: Several studies show that allogeneic peripheral blood stem cells (PBSCs) engraft more rapidly than bone marrow (BM). However, the data are inconsistent with regard to acute and chronic graft-versus-host disease (GVHD), relapse, transplant-related mortality (TRM), and leukemia-free survival (LFS).

PATIENTS AND METHODS: Between January 1994 and December 2000, 3,465 adult patients (older than 15 years of age) were reported to the European Group for Blood and Marrow Transplantation Registry from 224 centers. Among acute myeloid leukemia (AML) patients, 1,537 patients received BM and 757 patients received PBSC. In acute lymphoblastic leukemia (ALL) patients, the corresponding figures were 826 versus 345 patients who were analyzed for engraftment, GVHD, TRM, relapse, LFS, and survival.

RESULTS: In multivariate analysis, the recovery of neutrophils and platelets was faster with PBSC than with BM (P < .0001). Chronic GVHD was associated with PBSC in patients with AML (relative risk [RR], 2.11; 95% confidence interval, 1.66 to 2.7; P < .0001) and ALL (RR, 1.56; 95% confidence interval, 1.09 to 2.27; P = .02). PBSC versus BM in patients with AML or ALL was not significantly associated with acute GVHD, TRM, relapse, survival, or LFS. In multivariate analysis of patients with AML, factors significantly associated with improved LFS included first remission at transplant (P < .0001), promyelocytic leukemia (M3) versus other French-American-British types (P < .0001), and donor age below median 37 years (P = .02). In patients with ALL, first remission (P < .0001) and methotrexate included in the immunosuppressive regimen (P = .001) were associated with improved LFS.

CONCLUSION: Allogeneic PBSC results in faster neutrophil and platelet engraftment and a higher incidence of chronic GVHD than BM. However, acute GVHD, TRM, relapse, survival, and LFS were similar in patients receiving PBSCs versus BM.
Introduction of Chirality to the Remote, Open Face of a Metalloporphyrin through Coordination to the Metal of a Specially Designed Pendant Arm
Authors: Hamazawa Akihisa , Yano Toshihiro , Nishioka Takanori , Kinoshita Isamu , Isobe Kiyoshi , Yano Shigenobu , Wright L James , Collins Terrence J
Published: December 2002

Chirality has been introduced to a metalloporphyrin by a new approach that involves coordination to the metal of a pendant arm, with the preferred conformation adopted by the resulting chelate ring causing the meso-phenyl group to which the arm is attached to twist and thereby introduce chirality to the remote, open face of the metalloporphyrin.
Alkylation of Phenols by Oxidation-Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone and Alkoxydiphenylphosphine
Authors: Shintou Taichi , Kikuchi Wataru , Mukaiyama Teruaki
Published: December 2002

Various alkyl phenyl ethers were obtained in high yields by way of oxidation-reduction condensation where alkoxydiphenylphosphine, prepared easily from chlorodiphenylphosphine and corresponding alcohols, was treated with various phenols in the co-existence of 2,6-dimethyl-1,4-benzoquinone(DMBQ) under mild conditions.
Application of Carbon Nanotubes to Counter Electrodes of Dye-sensitized Solar Cells
Authors: Suzuki Kazuharu , Yamaguchi Makoto , Kumagai Mikio , Yanagida Shozo
Published: December 2002

In order to search for an efficient counter electrode in a dye-sensitized solar cells, three kinds of nano-carbon materials were examined. When single wall carbon nanotubes (SWCNTs) were used as a carbon electrode, the conversion efficiency of the cells is 4.5%. This value is comparable to Grätzel-type dye-sensitized solar cell (counter electrode: platiun-suputtered fluorine-doped tin oxide) under the same experimental condition.
A Novel in situ Template-controlled Route to CuS Nanorods via Transition Metal Liquid Crystals
Authors: Lu Jun , Zhao Yan , Chen Nan , Xie Yi
Published: December 2002

A novel and simple route, called in situ template-controlled (ISTC) method, has been developed to fabricate low-dimensional CuS nanorods by firstly taking advantages of TMLC’s semi-ordered arrangement.
Gas-Occlusion Properties of a Novel Compound: Mononuclear Copper(II) Terephthalate-Pyridine
Authors: Ohmura Tetsushi , Mori Wasuke , Hasegawa Mari , Takei Tohru , Yoshizawa Akira
Published: December 2002

Mononuclear copper(II) terephthalate-pyridine, which has a regular one-dimensional structure, occludes large amounts of gases. The maximum amount of N2 gas that can be occluded by mononuclear copper(II) terephthalate-pyridine is 1.1 mole per mole of copper(II) salt, indicating the presence of a large number of micropores. A porous structure, which is formed by hydrogen bonding and self-assembly of the linear copper(II) terephthalate-pyridine, was determined by X-ray crystallography.
Topotactic Preparation of Preferentially Oriented BaTiO3 and TiO2 Thin Films on Polycrystalline Substrate
Authors: Feng Qi , Kajiyoshi Koji , Yanagisawa Kazumichi
Published: December 2002

A layered titanate H1.08Ti1.73O4 oriented thin film on stainless steel and Ti metal substrates was prepared by using an exfoliation-restacking technique. The layered titanate film can be topotactically transformed to anatase and rutile thin films with preferred orientation along [103] and [110] directions, respectively, by heat-treatment, and to a BaTiO3 thin film with preferred orientation along [110] direction by hydrothermal treatment in a Ba(OH)2 solution.
Coexistence of multiple anomalies in the celiac‐mesenteric arterial system
Authors: Saeed Muhammad , Murshid Khalid R. , Rufai Amin A. , Elsayed Salah E.O. , Sadiq Muhammad Shakil
Published: December 2002

The origins and distribution of arteries of the celiac‐mesenteric system were examined by dissection of 52 formalin‐fixed human cadavers. Seventy‐five percent of the cadavers exhibited the classic Michels' Type I hepatolienogastric pattern; 25% had different branching patterns. Multiple anomalies of the celiac‐mesenteric arterial system were observed in one Caucasian female cadaver: a short lienogastric trunk; a common hepatic artery arising directly from the abdominal aorta; an anomalous course of the hepatic arteries; an accessory left hepatic artery arising from the left and right gastric arterial anastomosis along the lesser curvature of the stomach; a double cystic artery; a common inferior phrenic trunk arising from the celiac trunk; and an aberrant arterial channel connecting the proximal segments of the splenic and gastroduodenal arteries. A patent ductus venosus and an anomalous formation of the portal vein by the confluence of the splenic and superior and inferior mesenteric veins was also observed. Although single anomalies of the celiac‐mesenteric arterial system are common, complex combinations, such as were observed in the present case, represent a significant deviation from the normal developmental pattern. There seems to be no report in the literature of such a combination of anomalies coexisting in one individual. The developmental and clinical significance of these anomalous vessels is discussed. Clin. Anat. 16:30–36, 2003. © 2002 Wiley‐Liss, Inc.
Loss of lipopolysaccharide‐induced nitric oxide production and inducible nitric oxide synthase expression in scrapie‐infected N2a cells
Authors: Lindegren Heléne , Östlund Pernilla , Gyllberg Hanna , Bedecs Katarina
Published: December 2002

In scrapie‐infected cells, the conversion of the cellular prion protein to the pathogenic prion has been shown to occur in lipid rafts, which are suggested to function as signal transduction platforms. Neuronal cells may respond to bacterial lipopolysaccharide (LPS) treatment with a sustained and elevated nitric oxide (NO) release. Because prions and the major LPS receptor CD14 are colocalized in lipid rafts, the LPS‐induced NO production in scrapie‐infected neuroblastoma cells was studied. This study shows that LPS induces a dose‐ and time‐dependent increase in NO release in the murine neuroblastoma cell line N2a, with a 50‐fold increase in NO production at 1 μg/ml LPS after 96 hr, as measured by nitrite in the medium. This massive NO release was not caused by activation of the neuronal NO synthase (nNOS), but by increased expression of the inducible NOS (iNOS) mRNA and protein. However, in scrapie‐infected N2a cells (ScN2a), the LPS‐induced NO production was completely abolished. The absence of LPS‐induced NO production in ScN2a was due not to abolished enzymatic activity of iNOS but to a complete inhibition of the LPS‐induced iNOS gene expression as measured by Western blot and RT‐PCR. These results indicate that scrapie infection inhibits the LPS‐mediated signal transduction upstream of the transcriptional step in the signaling cascade and may reflect the important molecular and cellular changes induced by scrapie infection. © 2002 Wiley‐Liss, Inc.
Molecular and cellular cognitive studies of the role of synaptic plasticity in memory
Authors: Silva Alcino J.
Published: December 2002

Synaptic plasticity has a central role in nearly all models of learning and memory. Besides experiments documenting changes in synaptic function during learning, most of the evidence supporting a role for synaptic plasticity in memory comes from manipulations that either enhance or lesion synaptic processes. In the last decade, mouse transgenetics (knock outs and transgenics) have provided compelling evidence that the molecular mechanisms responsible for the induction and stability of synaptic changes have a critical role in the acquisition and storage of information. Here, I will review this literature, with a special focus on studies of hippocampal‐dependent learning and memory. © 2003 Wiley Periodicals, Inc. J Neurobiol 54: 224–237, 2003
Structural modeling of ataxin‐3 reveals distant homology to adaptins
Authors: Albrecht Mario , Hoffmann Daniel , Evert Bernd O. , Schmitt Ina , Wüllner Ullrich , Lengauer Thomas
Published: December 2002

Spinocerebellar ataxia type 3 (SCA3) is a polyglutamine disorder caused by a CAG repeat expansion in the coding region of a gene encoding ataxin‐3, a protein of yet unknown function. Based on a comprehensive computational analysis, we propose a structural model and structure‐based functions for ataxin‐3. Our predictive strategy comprises the compilation of multiple sequence and structure alignments of carefully selected proteins related to ataxin‐3. These alignments are consistent with additional information on sequence motifs, secondary structure, and domain architectures. The application of complementary methods revealed the homology of ataxin‐3 to ENTH and VHS domain proteins involved in membrane trafficking and regulatory adaptor functions. We modeled the structure of ataxin‐3 using the adaptin AP180 as a template and assessed the reliability of the model by comparison with known sequence and structural features. We could further infer potential functions of ataxin‐3 in agreement with known experimental data. Our database searches also identified an as yet uncharacterized family of proteins, which we named josephins because of their pronounced homology to the Josephin domain of ataxin‐3. Proteins 2003;50:355–370. © 2002 Wiley‐Liss, Inc.
Loss‐of‐function and residual channel activity of connexin26 mutations associated with non‐syndromic deafness
Authors: Bruzzone R. , Veronesi V. , Gomès D. , Bicego M. , Duval N. , Marlin S. , Petit C. , D'Andrea P. , White T.W.
Published: December 2002

Connexins are the protein subunits of gap junction channels that allow a direct signaling pathway between networks of cells. The specific role of connexin channels in the homeostasis of different organs has been validated by the association of mutations in several human connexins with a variety of genetic diseases. Several connexins are present in the mammalian cochlea and at least four of them have been proposed as genes causing sensorineural hearing loss. We have started our functional analysis by selecting nine mutations in Cx26 that are associated with non‐syndromic recessive deafness (DFNB1). We have observed that both human Cx26 wild‐type (HCx26wt) and the F83L polymorphism, found in unaffected controls, generated electrical conductance between paired Xenopus oocytes, which was several orders of magnitude greater than that measured in water‐injected controls. In contrast, most recessive Cx26 mutations (identified in DFNB1 patients) resulted in a simple loss of channel activity. In addition, the V37I mutation, originally identified as a polymorphism in heterozygous unaffected individuals, was devoid of function and thus may be pathologically significant. Unexpectedly, we have found that the recessive mutation V84L retained functional activity in both paired Xenopus oocytes and transfected HeLa cells. Furthermore, both the magnitude of macroscopic junctional conductance and its voltage‐gating properties were indistinguishable from those of HCx26wt. The identification of functional differences of disease causing mutations may lead to define which permeation or gating properties of Cx26 are necessary for normal auditory function in humans and will be instrumental in identifying the molecular steps leading to DFNB1.
Therapeutic trial in the first three Asian cases of ethylmalonic encephalopathy: Response to riboflavin
Authors: Yoon H‐R. , Hahn S. H. , Ahn Y. M. , Jang S. H. , Shin Y. J. , Lee E. H. , Ryu K. H. , Eun B. L. , Rinaldo P. , Yamaguchi S.
Published: December 2002

Three Korean girls with ethylmalonic encephalopathy, the first Asian cases, were identified. In all three cases, we observed slight improvement in motor functions, cognitive behaviours and chronic mucoid diarrhoea after treatment with riboflavin and/or coenzyme Q10 treatment. The precise pathogenesis of ethylmalonic encephalopathy has not been fully elucidated, but riboflavin treatment may be helpful.
Comparison of Symbol Sequences: No Editing, No Alignment
Authors: Sadovsky M. G.
Published: December 2002

The new method to compare two (or several) symbol sequences is developed. The method is based on the comparison of the frequencies of the small fragments of the compared sequences; it requires no string editing or other transformations of the compared objects. The comparison is provided through a calculation of the specific entropy of a frequency dictionary against the special dictionary called the hybrid one; the latter is the statistical ancestor of the group of sequences to be compared. Some applications of the method developed to genetics, bioinformatics, and linguistics are discussed.
2001 DIVISION 27 PRESIDENTIAL ADDRESS: Emotional Intelligence and the Good Community
Authors: Cherniss Cary
Published: December 2002

Suggests various ways in which the concept of emotional intelligence (EI) can inform community research and action. Begins by defining EI and reviewing the growing body of research on its contribution to educational, health, and occupational outcomes. Next distinguishes between EI and the related concept of emotional and social competence. Then considers the connection between EI and several topics of interest to community action researchers including prevention and wellness promotion, implementation and dissemination of innovative programs, community development, and the value of diversity. Concludes by suggesting that the ecological perspective can help inform research and practice relating to EI.
Ties to Influential Adults Among Black and White Adolescents: Culture, Social Class, and Family Networks
Authors: Hirsch Barton J. , Mickus Maureen , Boerger Rebecca
Published: December 2002

Although prior research suggests the importance of nonparental adults to adolescents, the ecological context of those relationships has received little attention. This study examined ties to influential adults among 122 adolescents who varied by race, family structure, and gender. The strongest effects were for race. Blacks reported stronger ties than Whites to the maternal grandmother as well as more supportive interactions with adult males. While race differences in grandparental ties were robust across social class (SES), ties to an influential adult male became nonsignificant upon controlling for SES. African American girls from divorced families consistently reported the strongest ties. Discussion considers the role of culture versus SES in explaining race differences. Implications for mentoring interventions are proposed, with special attention to the role of actualizing latent ties to already existing network members.
CMV hepatitis after liver transplantation: Incidence, clinical course, and long-term follow-up
Authors: Seehofer Daniel , Rayes Nada , Tullius Stefan G. , Schmidt Christian A. , Neumann Ulf P. , Radke Cornelia , Settmacher Utz , Müller Andrea R. , Steinmüller Thomas , Neuhaus Peter
Published: December 2002

Cytomegalovirus (CMV) hepatitis is described as the most frequent manifestation of CMV tissue invasive disease after liver transplantation. Its correlation with HLA-matching, hepatic artery thrombosis, and chronic rejection is still controversial. Risk factors, incidence, clinical course, and complications of CMV hepatitis were retrospectively analyzed in a 12-year series of 1,146 consecutive liver transplantations in 1,054 patients. All patients received only low-dose acyclovir but no gancyclovir prophylaxis. CMV infection was diagnosed by viral culture, pp65 antigenemia, or by polymerase chain reaction (PCR). CMV hepatitis was proven by liver biopsy. Treatment of CMV disease consisted of intravenous ganciclovir for a minimum of 14 days. Long-term follow-up of patients included monthly routine laboratory values and routine liver biopsies 1, 3 and 5 years after transplantation. CMV hepatitis was a rare event after liver transplantation, with a total incidence of 2.1% (24 cases). It was significantly more frequent in CMV seronegative (5.2%) than in seropositive recipients (0.7%). The leading indication in patients with CMV hepatitis was HCV cirrhosis (n = 8). The maximum number of pp65 positive white blood cells was 82 ± 23 per 10,000 cells. Most courses manifested as isolated hepatitis; only 2 patients had disseminated disease. Nine of 24 patients had received OKT3 monoclonal antibodies because of steroid-resistant rejection before CMV hepatitis. In seronegative patients with CMV hepatitis, 71% revealed 1 or 2 HLA DR matches, in contrast to 32% in patients without CMV hepatitis. One-, 3-, and 5-year graft survival was 78%, 65%, and 59% in patients with CMV hepatitis compared with 88%, 81%, and 79% in patients without. Chronic rejection was observed in one patient, but already before onset of CMV hepatitis. Beneath D+R−constellation and OKT3 treatment as risk factors, HLA DR-matched grafts and HCV seem to favor manifestation of CMV hepatitis after liver transplantation. Long-term complications of CMV hepatitis were not observed, and especially no correlation with chronic rejection was found.
Socioeconomic status does not affect the outcome of liver transplantation
Authors: Yoo Hwan Y. , Galabova Violetta , Edwin David , Thuluvath Paul J.
Published: December 2002

The outcome of liver transplantation is dependent on many factors. It was suggested that racial disparities in outcome may be related to differences in socioeconomic status (SES). In this retrospective study, we analyzed the effect of SES on graft and patient survival. Two hundred seventy-six adult patients who underwent liver transplantation at our institution from July 1988 to June 2001 were included in the analysis. Educational and occupation statuses were coded using established criteria (Hollingshead Index of Social Status [HI]). SES then was calculated using the HI formula: SES = education level × 3 + occupation × 5, and categorized into four groups: group 1, score less than 29 (n = 71); group 2, score of 29 to 42 (n = 82); group 3, score of 42 to 53 (n = 69); and group 4, score greater than 53 (n = 54). Kaplan-Meier analysis was used for graft and patient survival, and Cox regression analysis was used to determine the effect of confounding factors. Demographics of all four groups were similar. One-, 2-, and 5-year graft and patient survival did not differ significantly across groups by Kaplan-Meier and Cox regression survival analysis. In conclusion, SES did not predict graft and patient survival after liver transplantation.
Significance of positive cytotoxic cross-match in adult-to-adult living donor liver transplantation using small graft volume
Authors: Suh Kyung-Suk , Kim Sang Beom , Chang Seong-Hwan , Kim Seong Hoon , Minn Kyung Won , Park Myoung Hee , Han Kyou Sup , Lee Kuhn Uk
Published: December 2002

A positive cross-match in cadaveric liver transplantation is relatively acceptable, but its role in living donor liver transplantation (LDLT) is less well known. The aim of this study is to examine the significance of cytotoxic cross-match in adult-to-adult LDLT using small-for-size grafts. Forty-three adult-to-adult LDLTs were performed at Seoul National University Hospital (Seoul, Korea) from January 1999 to July 2001. Subjects consisted of 27 men and 16 women with an average age of 45.4 years. Average liver graft weight was 565.3 ± 145.7 g, and average graft-recipient weight ratio (GRWR) was 0.89% ± 0.20%. HLA cross-match testing by lymphocytotoxicity and flow cytometry was performed routinely preoperatively. Factors that may influence survival, such as age; sex; blood group type A, type B, type O compatibility; cytotoxic cross-match; donor age; surgical time; cold ischemic time; and GRWR, were analyzed. Nine patients (20.9%) died in the hospital. There was a greater in-hospital mortality rate in women than men (37.5% v 11.1%; P = .049). The extra-small-graft group (0.54% ≤ GRWR < 0.8%; n = 14) showed greater in-hospital mortality rates than the small-graft group (0.8% ≤ GRWR ≤ 1.42%; n = 29; 42.9% v 10.3%; P = .022). A positive cross-match was detected in 4 women transplant recipients, and 3 of these patients belonged to the extra-small-graft group. All patients with a positive cross-match died of multiorgan failure after early postoperative acute rejection episodes. Positive cross-match was the only significant factor in multivariate analysis (P = .035). In conclusion, when lymphocytotoxic cross-match and flow cytometry are significantly positive, adult-to-adult LDLT using small-for-size grafts should not be performed.
Plasma deposition of Ultrathin polymer films on carbon nanotubes
Authors: Shi Donglu , Lian Jie , He Peng , Wang L. M. , van Ooij Wim J. , Schulz Mark , Liu Yijun , Mast David B.
Published: December 2002

Ultrathin films of pyrrole were deposited on the surfaces of carbon nanotubes using a plasma polymerization treatment. High-resolution electron transmission microscopy images revealed that an extremely thin film of the polymer layer (2∼7 nm) was uniformly deposited on the outer and inner surfaces of the nanotubes. The nanotubes of all sizes exhibited equally uniform ultrathin films, indicating well-dispersed nanotubes in the fluidized bed reactor during the plasma treatment. In particular, the inner wall of the nanotube was also coated with a uniform ultrathin film of only ∼1–3 nm. Time-of-flight secondary ion mass spectroscopy experiments confirmed the highly branched and cross-linked polymer thin films on the carbon nanotubes. The plasma deposition mechanism is discussed in this letter.
STRUCTURAL PROPERTIES AND D.C. RESISTIVITY OF Li-Zn-Ti FERRITES
Authors: PHANJOUBAM SUMITRA , PRAKASH CHANDRA
Published: December 2002

In this paper we report influence of titanium substitution on the structural properties and d.c. conduction behavior of Li-Zn ferrites. The samples having the compositional formula Li 0.45+0.5t Zn 0.1 Ti t Fe 2.45-1.5t O 4 with t varying from 0 to 1.2 in steps of 0.2 were prepared by the conventional dry ceramic method. XRD analysis showed all the samples to be single phase spinel and the lattice parameter was found to increase with increasing t. D.C. resistivity increases with Ti concentration. The possible mechanisms involved are discussed.
Development and Validation of a Prognostic Model to Predict the Length of Survival in Patients With Carcinomas of an Unknown Primary Site
Authors: Culine Stéphane , Kramar Andrew , Saghatchian Mahasti , Bugat Roland , Lesimple Thierry , Lortholary Alain , Merrouche Yacine , Laplanche Agnès , Fizazi Karim
Published: December 2002

PURPOSE: To identify clinical and biologic variables with significant impact on survival in patients with carcinomas of an unknown primary site and to develop a simple prognostic model for the selection of patients in prospective clinical trials.

PATIENTS AND METHODS: Univariate and multivariate prognostic factor analyses were conducted in a population of 150 unselected patients and led to the construction of two successive classification schemes. An external data set of 116 patients enrolled onto two prospective trials was used for validation.

RESULTS: When studying clinical variables only, poor performance status (2 or 3) and presence of liver metastases were retained in the multivariate analysis. The first classification scheme consisted of three subgroups of patients with median survivals of 10.8, 6.0, and 2.4 months, according to the number of adverse prognostic factors. With the introduction of serum lactate dehydrogenase (LDH) levels in a further step, liver metastases were no longer significant. The second classification scheme therefore included poor performance status (relative risk [RR], 2.1) and elevated serum LDH level (RR, 2.1). Good-risk and poor-risk patients were identified, with median survivals of 11.7 months and 3.9 months, respectively (P < .0001). The 1-year survival rates were 45% and 11%, respectively. This second classification scheme was validated in an external data set: the median survival rates of patients assigned to the good-risk group and the poor-risk group were 12 months and 7 months, respectively (P = .0089). The 1-year survival rates were 53% and 23%, respectively.

CONCLUSION: A simple prognostic model using performance status and serum LDH levels was developed and validated. It allows the assignment of patients into two subgroups with divergent outcome. Further prospective trials will be designed using this prognostic model.
Chemoprevention of Melanoma: An Unexplored Strategy
Authors: Demierre Marie-France , Nathanson Larry
Published: December 2002

The incidence and mortality of melanoma has continued to increase steeply—faster than most other preventable cancers in the United States. Current sun protection strategies have yet to reduce this increased incidence and mortality. Chemoprevention, defined as the use of natural or synthetic agents to delay, reverse, suppress, or prevent premalignant molecular or histologic lesions from progressing to invasive cancer, has become an important area in cancer research. Melanoma, with its associated risk factors and its known precursors or premalignant lesions, should lend itself well to chemoprevention. Prerequisites for this research should include determination of the molecular mechanisms of ultraviolet (UV) melanomagenesis; use of animal models to test candidate prevention agents; use of molecular and histologic markers as surrogate end point markers; collection of epidemiological, basic science, or in vitro data on potential chemoprevention candidate drugs; and selection of a high-risk patient population in which to carry out clinical chemoprevention trials. Preliminary data available in all these areas are reviewed. Possible mechanisms and molecular targets for the chemoprevention of UV-induced melanoma are discussed. This recent information should stimulate research in the chemoprevention of melanoma.
Small-Mammal Data on Early and Middle Holocene Climates and Biotic Communities in the Bonneville Basin, USA
Authors: Schmitt Dave N. , Madsen David B. , Lupo Karen D.
Published: December 2002

Archaeological investigations in Camels Back Cave, western Utah, recovered a series of small-mammal bone assemblages from stratified deposits dating between ca. 12,000 and 500 14C yr B.P. The cave's early Holocene fauna includes a number of species adapted to montane or mesic habitats containing grasses and/or sagebrush (e.g., Lepus townsendii, Marmota flaviventris, Reithrodontomys megalotis, and Brachylagus idahoensis) which suggest that the region was relatively cool and moist until after 8800 14C yr B.P. Between ca. 8600 and 8100 14C yr B.P. these mammals became locally extinct, taxonomic diversity declined, and there was an increase in species well-adapted to xeric, low-elevation habitats, including ground squirrels, Lepus californicus and Neotoma lepida. The early small-mammal record from Camels Back Cave is similar to the 11,300–6000 14C yr B.P. mammalian sequence from Homestead Cave, northwestern Utah, and provides corroborative data on Bonneville Basin paleoenvironments and mammalian responses to middle Holocene desertification.
Late-Glacial and Early Holocene Environmental and Climatic Change at Lake Tambichozero, Southeastern Russian Karelia
Authors: Wohlfarth Barbara , Filimonova Ludmila , Bennike Ole , Björkman Leif , Brunnberg Lars , Lavrova Nadja , Demidov Igor , Possnert Göran
Published: December 2002

High-resolution lithostratigraphy, mineral magnetic, carbon, pollen, and macrofossil analyses, and accelerator mass spectrometry 14C measurements were performed in the study of a sediment sequence from Lake Tambichozero, southeastern Russian Karelia, to reconstruct late-glacial and early Holocene aquatic and terrestrial environmental changes. The lake formed ca. 14,000 cal yr B.P. and the area around the lake was subsequently colonized by arctic plants, forming patches of pioneer communities surrounded by areas of exposed soil. A minor rise in lake productivity and the immigration of Betula pubescens occurred ca. 11,500 cal yr B.P. The rise in summer temperatures probably led to increased melting of remnant ice and enhanced erosion. The distinct increase in lake productivity and the development of open Betula-Populus forests, which are reconstructed based on plant macrofossil remains, indicate stable soils from 10,600 cal yr B.P. onward. Pinus and Picea probably became established ca. 9900 cal yr B.P.
On Markovian Limit in Quantum Open Systems
Authors: Kossakowski Andrzej
Published: December 2002

The dynamics of spherical harmonic oscillator interacting with radiation field is investigated. It is shown that the irreversibility of time evolution is due to the appearance of resonances. Reduced dynamics is given in terms of multi-time correlation functions in the Markovian limit, which includes higher order corrections in the coupling constant.
The prevalence of posttraumatic stress disorder among American Indian Vietnam veterans: Disparities and context
Authors: Beals Janette , Manson Spero M. , Shore James H. , Friedman Matthew , Ashcraft Marie , Fairbank John A. , Schlenger William E.
Published: December 2002

This study employed data from two Congressionally mandated efforts (the American Indian Vietnam Veterans Project and the National Vietnam Veterans Readjustment Study) to examine differential prevalence of posttraumatic stress disorder (PTSD) among 5 ethnically defined samples of male Vietnam theater veterans. Lay interviews assessed individual experiences before, during, and after the war from 1,798 male Vietnam theater veterans. Clinical reinterviews using the SCID were conducted with subsamples (N = 487). The prevalence of both 1‐month and lifetime PTSD was higher for the 2 American Indian samples than for Whites. Once logistic regressions controlled for differential exposure to war‐zone stress, ethnicity was no longer a significant predictor of PTSD.
Migration, Social Security and the Law: Some European Dilemmas
Authors: Vonk Gijsbert
Published: December 2002

This article deals with the role of law in determining the position of migrants in the social security system against the background operation of specific migration policies. It is argued that the inclusion of migrants in the social security system can, in part, be explained in terms of the forces that have led to the gradual development of the right to social security. However, it appears that the quality of the treatment given to migrants in social security is strongly dependent upon the migration policies of the states concerned. It is not the existence of migration, but rather the perceived desirability of migration, which affects the legal position of migrants in social security. This has negative effects, in particular for asylum seekers, illegal immigrants and nationals from countries that are not covered by international social security obligations.
The role of total pressure in gas-phase nucleation: A diffusion effect
Authors: Suh S.-M. , Girshick S. L. , Zachariah M. R.
Published: December 2002

A numerical modeling study is presented concerning the role of total pressure in gas-phase nucleation. We consider a generic self-clustering mechanism for particle production in which the cluster transport properties are assumed to scale with monomer properties. A steady-state isothermal plug flow reactor model is considered in which axial diffusion of gas species is allowed. Species conservation equations with appropriate boundary conditions are solved in the one-dimensional reactor space. A steady-state nucleation current is shown to be achievable when the monomer concentration is fixed, regardless of the total pressure. In the case when the monomer concentration is varied, we demonstrate that diffusion can play a critical role at low pressures, where the nucleation rate is found to be highly pressure-sensitive. In this regime steady-state nucleation is not possible. As pressure increases, the nucleation rate becomes gradually pressure-insensitive and approaches the high-pressure limit. A dimensionless analysis is performed for a series of irreversible clustering reactions, and the effects of dimensionless system parameters on the nucleation rate are presented as a function of pressure. The results indicate that to minimize particle formation in chemical vapor deposition reactors while maintaining high deposition rates one should operate in the pressure-dependent regime, with low total reactor pressures and high partial pressures of reactants.
Effect of composite collector design on the breakdown behavior of InGaP/GaAs double heterojunction bipolar transistor
Authors: Lew K. L. , Yoon S. F.
Published: December 2002

A series of experiments and calculations has been carried out to study the effect of different composite collector designs on InGaP/GaAs/InGaP double heterojunction bipolar transistor breakdown characteristics. A comparison between uncorrected and dead-space corrected models was carried out, and it was found that the dead-space effect is dominant for collector thickness below 300 nm. However, this effect can be neglected for collector thickness larger than 500 nm. The role of lightly doped GaAs (n−-GaAs) and heavily doped InGaP (N+-InGaP) spacer layers is discussed systematically to establish a criterion for designing the composite collector structure. The experimental and theoretical results show that it is necessary to keep the sum of n−-GaAs and N+-InGaP spacer layer thickness below 50 nm to avoid significant degradation of the device breakdown characteristics.
Deformations of the Monge/Riemann hierarchy and approximately integrable systems
Authors: Strachan Ian A. B.
Published: December 2002

Dispersive deformations of the Monge equation ut=uux are studied using ideas originating from topological quantum field theory and the deformation quantization program. It is shown that, to a high order, the symmetries of the Monge equation may also be appropriately deformed, and that, if they exist at all orders, they are uniquely determined by the original deformation. This leads to either a new class of integrable systems or to a rigorous notion of an approximate integrable system. Quasi-Miura transformations are also constructed for such deformed equations.
Connections between second-order Görling–Levy and many-body perturbation approaches in density functional theory
Authors: Ivanov Stanislav , Hirata So , Grabowski Ireneusz , Bartlett Rodney J.
Published: December 2002

Formal connections between the high-density scaling limit of the correlation energy functional Ec[n] in density functional theory and second-order energy expressions from different perturbation theory formulations are presented. It is demonstrated that the second-order correlation potential considered by Grabowski et al. [J. Chem. Phys. 116, 4415 (2002)] is equivalent to the high-density limit of the exact correlation potential, and thus provides the first self-consistent finite-basis-set implementation of a Kohn–Sham (KS) potential correct through second-order. A different second-order correlation functional based on the exchange-only KS approach is introduced. It is shown that this second-order correlation functional leads to the same self-consistent KS realization as the one derived from the second-order component of Ec[n].
Formation and passivation kinetics of gold-hydrogen complexes in n-type silicon
Authors: Zamouche A.
Published: December 2002

Reverse- and zero-bias annealing kinetics of Au-related deep levels in Au diffused P-doped silicon hydrogenated by wet chemical etching, have been determined. The dynamic behavior of these deep levels can enable an estimation of the number of hydrogen atoms in the defects. Differences in the dynamic behavior during both reverse- and zero-bias annealing supports the suggestion that gold and hydrogen form at least two different electrically active complexes (AuH and AuH2) in n-type silicon.
Modeling the extended defect evolution in lateral epitaxial overgrowth of GaN: Subgrain stability
Authors: Romanov A. E. , Fini P. , Speck J. S.
Published: December 2002

The topic of extended defect structure stability in lateral epitaxial overgrowth (LEO) of GaN is addressed. We first summarize experimental results of growth morphology and dislocation structure in LEO GaN on sapphire substrates in the context of the crystallographic orientation of the stripe window openings. For 〈112̄0〉-oriented stripes, the LEO material often exhibits a triangular cross-section morphology with inclined {101̄1} facets. The threading dislocations (TDs) propagate vertically in the window region and then become unstable and bend toward the inclined sidewalls, to eventually lie in the basal plane. In the case of 〈11̄00〉-oriented stripes, vertical {112̄0} sidewalls may develop and, when realized, yield the lowest density of extended defects in the wing (overgrown) regions. Most of the TDs propagate vertically in the window regions and remain in loosely organized cell walls (subgrain boundaries). For this stripe orientation, a discernable crystallographic tilt of the LEO wing regions relative to the window region is also observed. This tilt is related to the appearance of edge dislocation arrays in the transition region between windows and wings. To understand the growth of dislocation-free wing regions, we present a model for dislocation subboundary cell structure stability during lateral overgrowth. The model provides a relation between structural parameters (such as cell size and misorientation) under which lateral defect-free growth is energetically favorable.