bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation Cohorts and Personal Values: A Comparison of China and the United States
Authors: Egri Carolyn P. , Ralston David A.
Published: April 2004

This study investigated the generation cohort value orientations of 774 Chinese and 784 U.S. managers and professionals. The three Chinese generations (Consolidation, Cultural Revolution, Social Reform) since the establishment of Communist China were significantly more open to change and self-enhancement but less conservative and self-transcendent than the Republican Era generation. The value orientations of U.S. generations (Generation X, Baby Boomer, Silent generation) followed an age-related pattern with the exception of self-transcendence values. The least similar value orientations were between Chinese and U.S. generations that had grown up during Communist China's closed-door policy. The more entrepreneurial value orientations of the most recent Chinese generations appear to be compatible with organizational changes currently under way in China's state-owned sector.
Employment Relationships in China: Do Workers Relate to the Organization or to People?
Authors: Hui Chun , Lee Cynthia , Rousseau Denise M.
Published: April 2004

This study investigates the contribution of organizational support and personal relations in accounting for Chinese workers' affective commitment to the organization for which they work and their organizational citizenship behavior. In a sample of 605 matched cases of employees and their immediate supervisors from a large, reformed state-owned firm, organizational support was found to relate to affective commitment more strongly than to organizational citizenship behavior. Personal relations, however, were found to relate similarly to affective commitment and organizational citizenship behavior. Moderator effects are evident with the less-traditional Chinese employees manifesting greater citizenship behavior than do more-traditional Chinese, in response to a high-quality relationship with their supervisor. More-traditional Chinese contribute citizenship behavior that is moderately high, regardless of the quality of their relationship with their supervisor. These findings suggest a need to revise certain assumptions regarding the nature of the employee-employer exchange relationship in China and in similar transitional societies.
Organizational Citizenship Behavior in the People's Republic of China
Authors: Farh Jiing-Lih , Zhong Chen-Bo , Organ Dennis W.
Published: April 2004

In recent years, Western scholars have increasingly emphasized the importance of organizational citizenship behavior (OCB)—employees' behavior and actions that are not specifically designated in their formal job duties. Almost the entire body of empirical research on OCB is based on studies conducted in the United States, using U.S. employee populations as samples. Taking an inductive approach, we examined forms of OCB in the People's Republic of China (China). From a diverse sample of 158 employees and managers in 72 state-owned, collective, town and village, foreign-invested, and private enterprises in China, we collected 726 OCB incidents or items that were commonly observed in the workplace. We then subjected these to a content analysis to identify major forms of OCB. Results of our analysis revealed 10 dimensions of OCB, with at least one dimension not evident at all in the Western literature, and four that do not figure importantly in established OCB measures. The type of Organizations influenced the reporting of several forms of OCB. Results suggested that Chinese formulation of OCB differs from that in the West, and is embedded in its unique social and cultural context. We discuss these results in terms of their implications for future research in OCB.
Organization and Management in the Midst of Societal Transformation: The People's Republic of China
Authors: Tsui Anne S. , Schoonhoven Claudia Bird , Meyer Marshall W. , Lau Chung-Ming , Milkovich George T.
Published: April 2004

Twenty-five years of economic reform has propelled China to the center of the world's economic stage. Based on current trends, in the foreseeable future China is likely to become the largest economy in the world. China's dramatic growth may be envied by other developing economies, but for management scholars it presents an exciting intellectual puzzle. In this paper we describe the empirical context of China today, review contemporary research on Chinese management and organizations, and describe the nine papers in this special issue of Organization Science. The papers provide a close examination of how massive corporate transformation in China has influenced interfirm relationships, affected opportunity structures and social processes, and modified individual behaviors within firms. We identify the many paradoxes in this intellectual terrain and present a guide to the challenging research agenda ahead. We recommend that scholars of organizations think deeply about China as a context and consider China as an empirical setting where the boundaries of existing knowledge on organizations can be extended.
Size Separation of Circulatory DNA in Maternal Plasma Permits Ready Detection of Fetal DNA Polymorphisms
Authors: Li Ying , Zimmermann Bernhard , Rusterholz Corinne , Kang Anjeung , Holzgreve Wolfgang , Hahn Sinuhe
Published: April 2004

Background: Analysis of fetal DNA in maternal plasma has recently been introduced as a new method for noninvasive prenatal diagnosis, particularly for the analysis of fetal genetic traits, which are absent from the maternal genome, e.g., RHD or Y-chromosome-specific sequences. To date, the analysis of other fetal genetic traits has been more problematic because of the overwhelming presence of maternal DNA sequences in the circulation. We examined whether different biochemical properties can be discerned between fetal and maternal circulatory DNA.

Methods: Plasma DNA was examined by agarose gel electrophoresis. The fractions of fetal and maternal DNA in size-fractionated fragments were assayed by real-time PCR. The determination of paternally and maternally inherited fetal genetic traits was examined by use of highly polymorphic chromosome-21-specific microsatellite markers.

Results: Size fractionation of circulatory DNA indicated that the major portion of cell-free fetal DNA had an approximate molecular size of <0.3 kb, whereas maternally derived sequences were, on average, considerably larger than 1 kb. Analysis of size-fractionated DNA (≤0.3 kb) from maternal plasma samples facilitated the ready detection of paternally and maternally inherited microsatellite markers.

Conclusions: Circulatory fetal DNA can be enriched by size selection of fragment sizes less than ∼0.3kb. Such selection permits easier analysis of both paternally and maternally inherited DNA polymorphisms.
Detection and Quantification of Heteroplasmic Mutant Mitochondrial DNA by Real-Time Amplification Refractory Mutation System Quantitative PCR Analysis: A Single-Step Approach
Authors: Bai Ren-Kui , Wong Lee-Jun C
Published: April 2004

Background: The A3243G mitochondrial tRNA leu(UUR) point mutation causes mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome, the most common mitochondrial DNA (mtDNA) disorder, and is also found in patients with maternally inherited diabetes and deafness syndrome (MIDD). To correlate disease manifestation with mutation loads, it is necessary to measure the percentage of the A3243G mtDNA mutation.

Methods: To reliably quantify low proportions of the mutant mtDNA, we developed a real-time amplification refractory mutation system quantitative PCR (ARMS-qPCR) assay. We validated the method with experimental samples containing known proportions of mutant A3243G mtDNA generated by mixing known amounts of cloned plasmid DNA containing either the wild-type or the mutant sequences.

Results: A correlation coefficient of 0.9995 between the expected and observed values for the proportions of mutant A3243G in the experimental samples was found. Evaluation of a total of 36 patient DNA samples demonstrated consistent results between PCR–restriction fragment length polymorphism (RFLP) analysis and real-time ARMS-qPCR. However, the latter method was much more sensitive for detecting low percentages of mutant heteroplasmy. Three samples contained allele-specific oligonucleotide-detectable but RFLP-undetectable mutations.

Conclusions: The real-time ARMS-qPCR method provides rapid, reliable, one-step quantitative detection of heteroplasmic mutant mtDNA.
Quantitative, Wide-Range, 5-Minute Point-of-Care Immunoassay for Total Human Chorionic Gonadotropin in Whole Blood
Authors: von Lode Piia , Rainaho Jarmo , Pettersson Kim
Published: April 2004

Background: Human chorionic gonadotropin (hCG) is among the most common analytes available for point-of-care immunotesting, with most assays currently based on simple manual assay devices. However, as the importance of good analytical performance of rapid assays is increasingly emphasized, more sophisticated immunoassay techniques are needed to meet the future challenges of rapid yet quantitative POC testing.

Methods: We developed a simple, dry-reagent, all-in-one immunoassay for the quantitative measurement of hCG in whole blood, plasma, or serum. The noncompetitive assay equally measures intact, nicked, and hyperglycosylated hCG as well as nonnicked and nicked hCG β-subunit with a rapid and simple procedure consisting of a 5-min, one-step incubation and, subsequent to washing, the measurement of time-resolved fluorescence directly from a wet well surface.

Results: The assay had a detection limit (background + 3 SD) of 0.4 IU/L hCG. The within-run CV was <15% down to 2 IU/L, and the assay was linear to 6000 IU/L. The within- and between-run CVs in heparinized whole blood and plasma were ≤10% throughout the measured range (4.0–4400 IU/L). The mean (95% confidence interval) difference between whole blood and plasma was −42 (−24 to −61)% without hematocrit correction and 6.5 (−14 to 27)% with hematocrit correction (n = 106). Regression analysis with the Diagnostic Products IMMULITE® 2000 hCG method yielded the following: slope (SD), 1.02 (0.01); y-intercept (SD), −6 (10) IU/L; Sy|x = 99 IU/L (n = 124; range, 1.6–4746 IU/L; r = 0.995).

Conclusions: Combined with the fully automated instrumentation, the 5-min, dry-reagent assay allows quantitative and reproducible determination of hCG in whole blood while sustaining the speed and simplicity of conventional rapid assays.
On the Palladium(II)‐Catalysed Oxidative Rearrangement of Propargylic Acetates
Authors: Bartels A. , Mahrwald R. , Müller K.
Published: April 2004

The catalytic transformation of propargylic acetates into the corresponding α‐acetoxyenones in the presence of palladium(II) chloride is described. Water is a necessary component in this unusual oxidative rearrangement.
Highly Enantioselective Copper‐Catalyzed Allylic Alkylation with Phosphoramidite Ligands
Authors: van Zijl Anthoni W. , Arnold Leggy A. , Minnaard Adriaan J. , Feringa Ben L.
Published: April 2004

New phosphoramidites were applied as chiral ligands in the Cu‐catalyzed allylic alkylation with dialkylzinc reagents. A variety of substrates, reagents and chiral ligands were screened, resulting in improved catalytic methodology for allylic bromides in which enantioselectivities up to 88% were reached.
Solventless Silane Alcoholysis Catalyzed by Recoverable Dirhodium(II) Perfluorocarboxylates
Authors: Biffis Andrea , Braga Mirko , Basato Marino
Published: April 2004

We have developed a novel reaction protocol for the highly efficient and sustainable catalysis of the silane alcoholysis reaction. The catalysts of choice are dirhodium(II) perfluorocarboxylates bearing long perfluoroalkyl chains, which are easily prepared in one step from commercial precursors. Under optimized reaction conditions, these catalysts exhibit up to about 50 times higher activity and 100 times higher productivity than analogous dirhodium(II) complexes described in the prior art. Furthermore, the reaction can be run in a completely solventless fashion. Finally, heterogenization of these catalysts has been accomplished through a novel strategy based on fluorous chemistry. Indeed, perfluorinated catalysts of this kind are easily adsorbed on silica which has been previously functionalized at its surface with perfluoroalkyl chains. Use of such supported catalysts (bonded fluorous phase catalysts) allows an easy and almost complete catalyst separation and recycling with improved catalytic performance.
Liquid–liquid phase separation in gravity settler with inclined plates
Authors: Schlieper Lars , Chatterjee Michael , Henschke Martin , Pfennig Andreas
Published: April 2004

Experimental investigations were made into the separation behavior of three different liquid–liquid dispersions in horizontal phase separators including internals. The test setup used, consisting of two separators of 200 mm diameter, enables direct comparative measurement of different internal configurations. The investigation focused on how inflow to the plates, the plate material, and the distance between the plates influenced separation length in the separator. Measurements performed for a range of total volume flows and phase ratios reveal that internals can achieve a reduction in the separation length required of up to 75% compared to that of a separator with no internals. It was also shown that discontinuous settling tests in a glass cylinder including internals can be used in achieving an initial engineering design for separators including internals. © 2004 American Institute of Chemical Engineers AIChE J, 50: 802–811, 2004
Porous anodic alumina microreactors for production of hydrogen from ammonia
Authors: Ganley Jason C. , Seebauer E. G. , Masel Richard I.
Published: April 2004

The synthesis and properties are described of a ruthenium‐impregnated anodic aluminum catalyst for use in microreactors for the production of hydrogen from an ammonia feed. The catalyst structure was synthesized using microelectric discharge machining to create a series of 300 × 300‐μm posts on an aluminum substrate. The posts were anodized to yield a 60‐μm covering of anodic alumina, with an average surface area of 16 m2/gm and an average pore size of 50 nm. Ruthenium metal was dispersed on the alumina using conventional wet impregnation. A 0.9 × 0.9‐cm reactor containing 250 posts decomposed 95% of anhydrous ammonia at 650°C to yield 15 sccm of hydrogen. A possible application of these microreactor fabrication methods is hydrogen generation for fuel cells in mobile power production. 2004 American Institute of Chemical Engineers AIChE J, 50:829–834, 2004
Effects of cigarette smoking on diagnostic tests for work‐related hypersensitivity pneumonitis: Data from an outbreak of lung disease in metalworkers
Authors: Dangman Kenneth H. , Storey Eileen , Schenck Paula , Hodgson Michael J.
Published: April 2004

Background

It is widely believed that development of hypersensitivity pneumonitis (HP) is forestalled in cigarette smokers. We encountered the largest outbreak of HP in metalworkers yet reported [Hodgson et al. (2001): Am J Ind Med 39:616–628] and subsequently did a chart review of the 61 patients seen in connection with the outbreak [Dangman et al. (2002a): Am J Resp Crit Care Med 165(8):A528; Dangman et al. (2002b): Am J Ind Med 42:150–162], developing a diagnostic index for this disease.

Methods

A re‐examination of data from the chart review was carried out to explore possible effects of cigarette smoking on the clinical tests used to diagnose HP [Hodgson et al. (2001): Am J Ind Med 39:616–628].

Results

Cigarette smokers with HP were less likely than non‐smokers with HP to develop crackles in the lungs, elevated erythrocyte sedimentation rates (ESRs), and restrictive spirometry. Smoking habits had little effect on diffusion capacity and alveolar‐arterial oxygen gradients in the patients with HP. Smokers were more likely to have abnormal gallium scans than non‐smokers.

Conclusions

It appears that cigarette smoking can affect the physical examination findings, spirometry, and ESR changes associated with HP, making these tests less sensitive and specific, and potentially obscuring the diagnosis. Such changes may contribute to the apparent “protective” effect of smoking on the development of HP. Am. J. Ind. Med. 45:455–467, 2004. Published 2004 Wiley‐Liss, Inc.
Spondyloepiphyseal dysplasia omani type: A new recessive type of SED with progressive spinal involvement
Authors: Rajab A. , Kunze J. , Mundlos Stefan
Published: April 2004

We report a large inbred kindred from Oman with a distinct type of spondyloepiphyseal dysplasia (SED). We evaluated eight individuals from two consanguineous sibships, one male and seven females between the ages of 2 and 22. The pedigrees strongly suggest autosomal recessive inheritance and both families are likely to be related through distant consanguineous loops. The clinical features include near to normal length at birth, short stature with final height of 110–130 cm, shortening of the upper segment due to severe progressive kyphoscoliosis, severe arthritic changes with joint dislocations, rhizomelic limbs, genu valgum, cubitus valgus, mild brachydactyly, camptodactyly, microdontia, and normal intelligence. Minor radiographic metaphyseal changes were found, but major manifestations were in the spine and the epiphyses. During the first year of life the vertebral bodies are of normal height but the endplates are irregular and intervertebral space is narrow. With age, the vertebral endplates become increasingly irregular, the intervertebral space diminishes further and individual vertebrae start to fuse resulting in a severe short trunk dwarfism with kyphoscoliosis. The epiphysis are small and precocious osteoarthropathy was observed involving small and large joints. The elbow, wrist, and hip joints were affected starting in infancy and showed restricted movement. Osteoarthropathy and spinal involvement resulted in physical handicap in early adulthood. Comparison of these patients with other skeletal dysplasias suggests that they represent a previously undescribed variant of SED. © 2003 Wiley‐Liss, Inc.
X‐linked cardioskeletal myopathy and neutropenia (Barth syndrome): An update
Authors: Barth Peter G. , Valianpour Fredoen , Bowen Valerie M. , Lam Jan , Duran Marinus , Vaz Frédéric M. , Wanders Ronald J.A.
Published: April 2004

X‐linked cardioskeletal myopathy and neutropenia (Barth syndrome, MIM302060, BTHS) is a disorder with mitochondrial functional impairments and 3‐methylglutaconic aciduria that maps to Xq28. The associated G4.5 or TAZ gene has been identified but the encoded proteins have not yet been characterized. Following the prediction that the gene encodes one or more acyltransferases, lipid studies have shown a deficiency of cardiolipin, especially its tetralinoleoyl form (L4‐CL). Deficiency of L4‐CL was subsequently demonstrated in a variety of tissues, and determination in thrombocytes or cultured skin fibroblasts is now the most specific biochemical test available. BTHS is the first identified inborn error of metabolism that directly affects cardiolipin, a component of the inner mitochondrial membrane, necessary for proper functioning of the electron transport chain. We report here the finding of deficient docosahexaenoic acid and arachidonic acid in a proportion of patients with BTHS. The initial impression of a uniformly lethal infantile disease has to be modified. Age distribution in 54 living patients ranges between 0 and 49 years and peaks around puberty. Mortality is the highest in the first 4 years. The apex of the survival curve around puberty and the emergence of adults may reflect a dynamic shift towards increased survival. This trend is exemplified in a large pedigree previously published. © 2004 Wiley‐Liss, Inc.
A severe form of amyloidotic polyneuropathy in a Costa Rican family with a rare transthyretin mutation (Glu54Lys)
Authors: Busse Andreas , Sánchez María A. , Monterroso Victoria , Alvarado Marco V. , León Pedro
Published: April 2004

Four affected siblings in a Costa Rican family presented an aggressive polyneuropathy with widespread involvement of many visceral organs and onset during the third decade of life with rapid loss of muscle mass in the lower limbs and severe dysautonomy. The medical histories include vitreous opacity, cardiac enlargement, dermal and gastrointestinal infiltration, and autonomic dysfunction including circulatory compromise and gastrointestinal disturbances. Histological studies using Congo red stain and immunohistochemical assays with antibodies against the transthyretin (TTR) protein showed widespread deposition of amyloid in extracellular areas, including dermis and gastrointestinal lamina propia, endo‐ and perineural spaces, and vascular walls. A mutation search in the transthyretin (ttr) gene was performed seeking the cause of this severe form of familial amyloidotic polyneuropathy (FAP). We applied single‐stranded conformational polymorphism (SSCP)‐analyses followed by sequencing of the four exons of the ttr gene, revealing a point mutation in exon 3, a G to A transition that causes a Glu54Lys codon change. Western blots of plasma proteins incubated with anti‐transthyretin antibodies after gel electrophoresis provided separation of wild‐type and mutant TTR protein in affected family members. © 2004 Wiley‐Liss, Inc.
Osteocyte dendrogenesis in static and dynamic bone formation: An ultrastructural study
Authors: Palumbo Carla , Ferretti Marzia , Marotti Gastone
Published: April 2004

The present ultrastructural investigation into osteocyte dendrogenesis represents a continuation of a previous study (Ferretti et al., Anat. Embryol., 2002; 206:21–29), in which we pointed out that, during intramembranous ossification, the well‐known dynamic bone formation (DBF), performed by migrating osteoblast laminae, is preceded by static bone formation (SBF), in which cords of stationary osteoblasts transform into osteocytes in the same site where they differentiated. The research was carried out on the perichondral center of ossification surrounding the mid shaft level of various long bones of chick embryos and newborn rabbits. Transmission electron microscope observations showed that the formation of osteocyte dendrites is quite different in the two types of osteogenesis, mainly depending on whether or not osteoblast movement occurs. In DBF, osteoblasts transform into small ovoidal/ellipsoidal osteocytes and their dentrites form in an asynchronous and asymmetrical manner in concomitance with, and depending on, the advancing mineralizing surface and the receding osteogenic laminae. In SBF, stationary osteoblasts give rise to big globous osteocytes, located inside confluent lacunae, with short and symmetrical dendrites that can radiate simultaneously all around their cell body because they are completely surrounded by unmineralized matrix. Contacts and gap junctions were observed between all osteocytes (both SBF‐ and DBF‐derived) and between osteocytes and osteoblasts. Finally, a continuous osteocyte network extends throughout the bone, regardless of its static or dynamic origin. This network has the characteristic of a functional syncytium, potentially capable of modulating, by wiring transmission, the cells of the osteogenic lineage covering the bone surfaces. Anat Rec Part A 278A:474–480, 2004. © 2004 Wiley‐Liss, Inc.
Synthesis and Evaluation of Anticonvulsant and Antimicrobial Activities of 3‐Hydroxy‐6‐methyl‐2‐substituted 4H‐Pyran‐4‐one Derivatives
Authors: Aytemir Mutlu Dilsiz , Çaliş Ünsal , Özalp Meral
Published: April 2004

In this study, thirteen 3‐hydroxy‐6‐methyl‐2‐substituted 4H‐pyran‐4‐one derivatives were synthesized for the evaluation of their potential anticonvulsant activity. Mannich bases were prepared by the reaction of substituted piperazine derivatives with allomaltol and formaline. The structures of the synthesized compounds were confirmed by IR, 1H‐NMR and elemental analysis. Their anticonvulsant activities were determined in vivo by maximal electroshock (MES), sub‐cutaneous Metrazol (scMet), and rotorod toxicity tests for neurological deficits. The antimicrobial activities of the synthesized compounds were investigated in vitro against some bacteria and fungi using the microdilution broth method. Ac‐cording to the activity studies, 3‐hydroxy‐6‐methyl‐2‐[4‐(2‐trifluoromethyl‐phenyl)‐piperazin‐1‐ylmethyl]‐4H‐pyran‐4‐one (3i) was the compound determined to be most active in the scMet test for all doses at four hours and for the 300 mg/kg dose at half an hour. 2‐[4‐(4‐Chloro‐phenyl)‐piperazin‐1‐ylmethyl]‐3‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one (3f) was found to be protective against MES whereas 2‐chlorophenyl derivative (3e) was not. Looking at the antifungal activity results, compounds 3b, 3h, and 3i were determined to have activity against all fungi.
Novel Antiprotozoal Products: Imidazole and Benzimidazole N‐Oxide Derivatives and Related Compounds
Authors: Aguirre Gabriela , Boiani Mariana , Cerecetto Hugo , Gerpe Alejandra , González Mercedes , Sainz Yolanda Fernández , Denicola Ana , de Ocáriz Carmen Ochoa , Nogal Juan José , Montero David , Escario José Antonio
Published: April 2004

The syntheses and biological evaluation of the first anti‐protozoa imidazole N‐oxide and benzimidazole N‐oxide and their derivatives are reported. They were tested in vitro against two different protozoa, Trypanosoma cruzi and Trichomonas vaginalis. Derivative 7c, ethyl‐1‐(i‐butyloxycarbonyloxy)‐6‐nitrobenzimid‐azole‐2‐carboxylate, displayed activity on both protozoa. Lipophilicity and redox potential were experimentally determined in order to study the relationship with activity of the compounds. These properties are well related with the observed bioactivity. Imidazole and benzimidazole N‐oxide derivatives are becoming leaders for further chemical modifications and advanced biological studies.
Aging properties of the residual life length of k‐out‐of‐n systems with independent but non‐identical components
Authors: Li Xiaohu , Chen Jing
Published: April 2004

The k‐out‐of‐n structure is a very popular type of redundancy in fault‐tolerant systems, it has founded wide applications in industrial and military systems during the past several decades. This paper will investigate the residual life length of a k‐out‐of‐n system with independent (not necessarily identical) components, given that the (n−k)th failure has occurred at time t⩾0. Behaviour of PF2, IFR, DRHR, DMRL, NBU(2) and NBUC classes of life distributions are derived in terms of the monotonicity of the residual life given the time of the (n−k)th failure. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of the CuA center in the cytochrome c oxidase from Thermus thermophilus for the spectral range 1800–500 cm−1 with a combined electrochemical and Fourier transform infrared spectroscopic setup
Authors: Wolpert M. , Maneg O. , Ludwig B. , Hellwig P.
Published: April 2004

In this study we present the electrochemically induced Fourier transform infrared (FTIR) difference spectra of the CuA center derived from the ba3‐type cytochrome c oxidase of Thermus thermophilus in the spectral range from 1800 to 500 cm−1. The mid infrared is dominated by the ν(CO) vibrations of the amide I modes at 1688, 1660, and 1635 cm−1, reflecting the redox‐induced perturbation of the predominantly β‐sheet type structure. The corresponding amide II signal is found at 1528 cm−1. In the lower frequency range below 800 cm−1, modes from amino acids liganding the CuA center are expected. On the basis of the absorbance spectrum of the isolated amino acids, methionine is identified as an important residue, displaying C—S vibrations at these frequencies. This spectral range was previously disregarded by protein IR spectroscopists, mainly due to the strong absorbance of the solvent, H2O. With an optimized setup, however, IR is found suitable for structure/function studies on proteins. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Exogenous compounds in studying the mechanism of electron‐excited state formation in bioluminescence
Authors: Kudryasheva N. S. , Nemtseva E. V. , Kirillova T. N.
Published: April 2004

Using a series of exogenous fluorescent molecules as potential energy acceptors, the hypothesis on the activity of the upper electron‐excited states in bioluminescence was tested. The results in bacterial and firefly bioluminescent enzyme systems were compared. Similar activity to the energetic precursor in bacterial bioluminescence was not proven in the case of the firefly system, the result of a very efficient intramolecular energy transfer in the emitter of the firefly bioluminescence. The influence of a number of metallic salts on a bacterial bioluminescent enzyme system was studied. Bioluminescence inhibition coefficients were compared to the free energies of electron withdrawing of cations. The correlation shows that inhibition and activation of luminescence intensity result from the effects of cations on electron transfer in the bioluminescent system. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Fast relaxation processes and structural changes in immunoactive biomolecules
Authors: Borisevich N. A. , Dubovsky V. L. , Mikhalchuk A. L. , Raichyonok T. F. , Tikhomirov S. A. , Tolstorozhev G. B.
Published: April 2004

Based upon an analysis of the absorption spectra, the fluorescence and fluorescence excitation spectra, and the lifetime of the excited states of aqueous solutions (pH 7.4) of 2,3‐dimethoxy‐8‐azagona‐1,3,5(10),13‐tetraene‐12,17‐dione, it is established that two centers of different type exist: one emits long‐wave (L‐centers) and the other short‐wave (S‐centers) fluorescence. Irradiation of solutions increases the number of L‐centers and greatly decreases that of S‐centers. Examination of the picosecond transient absorption spectra and their kinetics revealed that the initial photochemical stage is defined as the ionization of a considered molecule and the subsequent one, as the formation, most probably, of the dehydroderivative of a parent molecule. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Sentinel lymph node detection in primary melanoma with preoperative dynamic lymphoscintigraphy and intraoperative γ probe guidance
Authors: Tiffet O , Perrot J L , Gentil-Perret A , Prevot N , Dubois F , Alamartine E , Cambazard F
Published: April 2004

Background

This study assessed the value of the radioisotopic method used alone, and factors influencing relapse rates, for sentinel lymph node (SLN) mapping in primary melanoma.

Methods

One hundred and thirty-three patients with a diagnosis of melanoma (thickness greater than 0·75 mm) underwent γ probe-directed lymphatic mapping in a prospective single-centre study.

Results

Mean Breslow thickness was 3 mm. At least one SLN was identified in 132 patients (mean 1·8 nodes per patient); the success rate was 99·2 per cent. Twenty-two patients (16·7 per cent) had a metastasis within the SLN. The mean tumour thickness in patients with a metastatic SLN was 4·4 mm compared with 2·7 mm for patients with a negative SLN (P < 0·001). The median time to recurrence was 20·4 months in SLN-negative patients compared with 8·5 months in those with SLN metastasis (P < 0·001). Ten (9·1 per cent) of the 110 SLN-negative patients developed recurrence. Three patients relapsed in the previously mapped lymphatic basin after a median follow-up of 27·1 months.

Conclusion

This study confirmed the reliability and accuracy of SLN mapping using a radioisotope technique, and also the importance of the SLN as a predictive factor for survival. There was a low risk of locoregional recurrence when the SLN was not involved.
Entwicklungen im Waagenbau: Antworten auf die Globalisierung
Authors: Oldendorf Christian
Published: April 2004

Moderner Waagenbau mit seiner hochentwickelten Funktionalität ist einer hohen Dynamik unterworfen. Was vor 100 Jahren noch in einer technischen Werkstatt entstehen konnte, wird heute in einem ausgeklügelten weltweiten Geflecht gefertigt und zum Kunden gebracht.
Ein gelungenes Lexikon — und das umsonst
Authors: Roth Klaus
Published: April 2004

Buchbesprechung: Chemiker von A‐Z — Eine biografischlexikalische Übersicht über die Chemie und ihre bedeutendsten Vertreter in Ostdeutschland von Chemieverbände Nordost, Berlin
Färben in überkritischem Kohlendioxid
Authors: Feil Sylvia
Published: April 2004

Wasser ist das Medium, das bislang vorrangig beim Färben von Textilien eingesetzt wird. Eine Alternative könnte das Färben in überkritischem Kohlenstoffdioxid werden.
Molecular dissection of the fibroblast‐traction machinery
Authors: Sawhney Ravi K. , Howard Jonathon
Published: April 2004

Motile fibroblasts generate forces that can be expressed as cell migration or as traction, the drawing‐in of extracellular matrix. Traction by cultured fibroblasts can induce a rapid concerted reorganization of collagen gel, creating a pattern of collagen alignment similar to that seen in tendons and ligaments. In such fibrous connective tissues, after pattern morphogenesis is complete, ongoing traction may be responsible for the maintenance of proper form and function. The molecules that generate and transmit forces have been catalogued; however, how these nanometer‐scale molecules contribute to millimeter‐scale patterns has not been directly tested. Here, we placed pairs of explants of human periodontal ligament fibroblasts in collagen gels, where ligament‐like straps of anisotropic collagen formed on the axes between them. We scrutinized the traction apparatus using electron microscopy, video microscopy, and computer‐based pattern analysis, augmented with pharmacologic inhibitors of cytoskeletal function. Patterning was marked by the co‐alignment of collagen, fibroblasts, and their actin cytoskeletons, all parallel to the axis between explants. The pattern was diminished by depolymerizing actin filaments or by blocking myosin activity, but was accentuated by depolymerizing microtubules. The plasma membrane also seems to contribute to the traction force. These molecular components combine to exert a sub‐maximal traction force on the matrix, suggesting that the force may be regulated to ensure tissue tensional homeostasis. Cell Motil. Cytoskeleton 58:175–185, 2004. © 2004 Wiley‐Liss, Inc.
The development of interval breast malignancies in patients with BRCA mutations
Authors: Komenaka Ian K. , Ditkoff Beth‐Ann , Joseph Kathie‐Ann , Russo Donna , Gorroochurn Prakash , Ward Marie , Horowitz Elizabeth , El‐Tamer Mahmoud B. , Schnabel Freya R.
Published: April 2004

BACKGROUND

At present, there is no consensus regarding how frequently BRCA mutation carriers should be screened for malignancies using breast imaging techniques. An interval malignancy is defined as a malignancy that becomes evident during the period between annual screening mammography scans; the finding of such a malignancy indicates that the malignancy either went undetected by the last breast imaging scan or developed during the interval since that last scan.

METHODS

The authors retrospectively reviewed the medical charts of all BRCA mutation carriers who were followed by the genetic counselor at the Columbia‐Presbyterian Comprehensive Breast Center (New York, NY) between September 1995 and September 2002.

RESULTS

Thirteen BRCA mutation carriers elected to undergo close surveillance and thus were followed at our institution. Three of these 13 patients (23%) did not develop breast carcinoma, 4 (31%) developed breast carcinoma that was detected at the time of annual screening, and 6 (46%) developed palpable interval malignancies in less than 12 months. Among the six patients who developed interval malignancies, the mean time between the last screening mammogram and disease presentation was 5.1 months (range, 2–9 months); the average tumor size in this patient subgroup was 1.7 cm (range, 0.8–3 cm). Two of these six patients had ductal carcinoma in situ, whereas the remaining four had invasive breast carcinoma; three patients had positive lymph nodes at presentation. All six patients who developed interval disease exhibited dense breast tissue on the previous mammogram. Focused breast ultrasonography was able to identify the tumor mass in 3 of 4 patients (75%).

CONCLUSIONS

Nearly half of all BRCA‐positive women who chose to undergo close surveillance in the current study developed malignant disease less than a year after exhibiting normal findings on screening mammography. Half of these interval malignancies were positive for lymph node involvement. These results suggest that strong consideration should be given to screening BRCA‐positive women at more frequent intervals and to using additional imaging techniques, such as breast ultrasonography and/or breast magnetic resonance imaging, as a part of this screening. Cancer 2004. © 2004 American Cancer Society.
Analysis of random access channel in UTRA‐TDD on AWGN channel
Authors: Yang Yang , Yum Tak‐Shing Peter
Published: April 2004

The random access channel (RACH) in UTRA‐TDD systems is an uplink contention‐based transport channel that is mainly used to carry control information from mobile stations to base stations. In this paper, we study the performance of RACH on an additive white Gaussian noise (AWGN) channel whereby successful transmission of a burst requires the spreading code chosen to be collision‐free and the burst is error‐free after convolutional decoding. Based on this model, the code‐collision probability, the data bit error probability and the RACH channel capacity are derived. The random retransmission delay mechanism is not specified in UTRA‐TDD. We therefore choose an access mechanism with binary exponential backoff delay procedure similar to that in IEEE 802.11. Based on that mechanism, the blocking probability and the first two moments of the delay are also derived. Compared with the mean, the standard deviation is found to be very high. Copyright © 2004 John Wiley & Sons, Ltd.
An entropy estimator improving mean squared error
Authors: Yokota Yasunari , Shiga Motoki
Published: April 2004

Entropy estimation for a memory‐less information source has mainly been performed by the following process under the condition that the occurrence probability of each source symbol is unknown: First, the occurrence probabilities of source symbols are estimated; then the entropy is estimated by substituting the estimated occurrence probabilities into the entropy function. Such an entropy estimation is not optimum in the sense of least squares error; it causes a large error, particularly for small sample size. In this paper, we propose an entropy estimator that strictly minimizes the mean squared error for a two‐ary memory‐less information source; it is formulated as a function of the number of one type of source symbols contained in the sample set. Furthermore, we propose a technique for estimating entropy of an arbitrary M‐ary memory‐less information source by recursively applying the proposed entropy estimator for a two‐ary memory‐less information source. Numerical experiments show that this technique improves mean squared error compared to the conventional method even though the guarantee that it is the least squares error estimator has been lost. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 1–10, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10163
A watermarking scheme without reference images for broadcast monitoring
Authors: Tachibana Takashi , Fujiyoshi Masaaki , Kiya Hitoshi
Published: April 2004

In this paper, to automate broadcast monitoring, which is typified by the verification of the transmission of the material ID code of a commercial message (CM) or program, the authors propose a watermarking scheme without reference images, which does not require a reference image when the watermark sequence is extracted. By embedding a watermark sequence formed by using standard normal random numbers after discretizing the embedding‐target coefficients in the DCT domain, the proposed technique makes a reference image unnecessary when the watermark sequence is extracted. In addition, since the proposed technique enables a watermark image having the desired image quality (PSNR) to be achieved for any image, it has the advantage that the image quality can always be maintained regardless of the image. Therefore, the same procedure can always be used to embed the watermark sequence in a full‐motion video image without obtaining parameters for each image and to extract that watermark sequence without using a reference image. The authors used simulations to verify that an image quality of at least 56 dB, which is the HDTV digital VTR guideline, can be maintained even in the watermarked image, that the watermark sequence can be extracted without using a reference image, and that the proposed technique is robust with respect to MPEG. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 22–32, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20101
Fast feedback control of plasma horizontal position by using DSP and IGBT inverter
Authors: Toyoda Mitsuhiro , Kikuchi Yusuke , Uesugi Yoshihiko , Takamura Shuichi
Published: April 2004

To achieve high confinement properties of a tokamak plasma, it is necessary to control the plasma position, current profile, shape of magnetic surface, and so on. In addition, it has been found that a resistive wall mode (RWM) may limit the achievable plasma beta in present tokamak devices. Therefore, it is expected that an active feedback control using external coils is necessary to stabilize the RWM. A power supply for plasma control coils requires an accurate controllability and a fast response against such plasma disturbances. Recent development of high‐power fast‐switching semiconductors, such as Insulated Gate Bipolar Transistor (IGBT) and MOSFET, improves the temporal response of power supply to a great extent. A small tokamak device, HYBTOK‐II, is equipped with IGBT inverter power supplies for Joule and vertical field coils. In this paper a real‐time feedback control of the plasma horizontal position has been employed with a Digital Signal Processor (DSP). The experimental results on plasma response with such a feedback control have been compared with analysis of plasma column motion using transfer functions. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 1–10, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10295
A control strategy for active filters using quasi‐instantaneous positive sequence extraction filters
Authors: Furukawa Kouji , Tarafdar Haque M. , Ise Toshifumi , Kumagai Sadatoshi
Published: April 2004

A novel control strategy for active filters, employing quasi‐instantaneous positive sequence extraction of utility voltage, can be useful in harmonic polluted and/or imbalanced utility voltage. In this paper, the authors examined its transient response, its performance under the change of fundamental frequency of utility voltage and its performance under utility voltage with harmonics and unbalance. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 54–65, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10307
A multi‐teacher learning automata computing model for graph partitioning problems
Authors: Ikebo Shigeya , Qian Fei , Hirata Hironori
Published: April 2004

Graph partitioning is an important problem that has extensive applications in many areas, including VLSI design, scientific computing, data mining, geographical information systems, and job scheduling. The graph partitioning problem (GPP) is NP‐complete. There are several heuristic algorithms developed for finding a reasonably good solution. The most famous partitioning methods are simulated annealing (SA) and the mean field algorithm (MFA), both known to produce good partitioning for a wide class of problems, and they are used quite extensively. However, these methods are very expensive in terms of time and very sensitive to parameter tuning methods. In this paper, a new parameter‐free algorithm for GPP has been proposed. The algorithm has been constructed using the S‐model learning automata with multi‐teacher random environments. As shown in our experiments, the proposed algorithm has some advantages over SA, MFA, and ParMeTiS. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 46–53, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10310
Characteristics of thin film deposition by photo‐CVD using a Xe2 excimer lamp
Authors: Miyano Junichi , Yokotani Atsushi , Kurosawa Kou
Published: April 2004

Recently, a novel method of photochemical vapor deposition using vacuum ultraviolet (VUV) excimer lamps (VUV‐CVD) has been developed. We have been attempting to make thin films from organic precursors at room temperature by VUV‐CVD. We present the characteristics of VUV‐CVD films and the reaction properties of VUV‐CVD as a function of the addition of O2, the substrate temperature, and the illumination intensity, examining the growth rate, film quality, and gap‐filling properties when various organic siloxane gases are used as chemical precursors. VUV photons dissociate the organic precursor and produce radical reactants that consist of Si‐O and impurities such as C‐H and O‐H. They finally condense into deposition films including SiO2 and impurities. Therefore, the VUV‐CVD films are very similar in composition to the precursors. The reaction is altered by adding O2, which produces ozone and activated oxygen as a result of dissociation by VUV photons. The deposition efficiency is improved by both a low substrate temperature and the higher light intensity of the excimer lamp. Film deposition at room temperature in VUV‐CVD without thermal‐ or plasma‐induced damage constitutes an important innovation in thin film preparation. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 43–50, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10325
Prediction of the operational impedance of rotating machines by various DC testing methods
Authors: Yamamoto Shu , Gotou Takashi , Ara Takahiro
Published: April 2004

This paper presents methods to determine the operational impedance of rotating machines by Fourier transformation of the voltage and current measured when a step (or pulse) voltage is applied to the two stator winding terminals. These standstill tests using a small‐capacity DC power supply unit are tentatively termed DC testing methods. We also describe in detail the case using a DC power source with ripple and the case in which a step (or pulse) voltage is applied with current flowing. These methods are applied to a 5.5‐kW squirrel‐cage induction motor having semiclosed rotor slots. The validity of the proposed prediction methods is demonstrated by comparing the calculated and measured speed characteristics of the tested induction machine. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 51–59, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10348
Two Contrasting Asymmetric Approaches to Muscarine Based on 5‐endo‐trig Cyclisations
Authors: Knight David W. , Shaw Duncan E. , Staples Emily R.
Published: April 2004

5‐endo‐trig cyclisation of the (Z)‐hydroxyalkenoate 17 using iodine as the electrophile gave a good yield of the β‐hydroxytetrahydrofuran 18, probably via the corresponding iodohydrin. A variety of one‐carbon degradation methods were then used to generate precursors to (−)‐muscarine (25d). An alternative strategy featured control of a 5‐endo‐trig iodocyclisation by an allylic hydroxyl group, which can be used for the highly stereocontrolled synthesis of hydroxy‐iodotetrahydrofurans 28. Application of this strategy to the (Z)‐alkenediol derivative 38 led to an excellent yield of the tetrahydrofuran 39 when iodine monobromide was used as the electrophile. Two simple and efficient transformations then gave the (+)‐muscarine precursor 40b. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)