bluuebunny/crossref_metadata_2025 huggingface dataset:
59.3: Paving the Way for Novel Top‐Emitting AMOLED Architecture through New Cathode and ETL Materials
Authors: Lee Jong Hyuk , Kim Won‐Jong , Yang Seung Gak , Lee Chang Ho , Kim Yong Tak , Shin Jung Han , Choi Jin Baek , Kim Hee Yeon , Ko Hee Joo , Zang Dong Sik , Chung Ho Kyun
Published: August 2007

A novel top‐emitting AMOLED structure with transparent cathode has been successfully developed. Newly designed thermal deposition enabled to avoid damages to organic layers and to realize totally transparent conducting oxide cathode material with low work‐function. Besides, new ETL material with excellent electron transporting characteristics has been designed and synthesized for the new top‐emitting structure. Owing to the breakthrough in the transparent cathode and ETL materials, we could make a progress in overcoming the drawbacks of current microcavity‐ structured top‐emitting AMOLED architecture.
60.3: Advanced Application of Direct Laser Process on SnO2 Thin Films for FPDs
Authors: Usui Reo , Mihara Yu , Satoh Ryohei , Mihara Yu , Morinaga Eiji , Iwata Yoshiharu
Published: August 2007

A Nd:YAG laser process on pure and doped SnO2 thin films was investigated as a key technology for a next generation flat panel displays manufacture replacing photolithography etching process on Indium‐Tin‐Oxide that is currently in use. It is found that the laser process is capable of making fine micro patterns on SnO2 thin films that have high carrier concentration by as low laser energy as 6J/cm2.
60.4: Single Layer Al‐Ni Interconnections for TFT‐LCDs using Direct Contacts with ITO and a‐Si
Authors: Kugimiya Toshihiro , Yoneda Yoichiro , Yoshikawa Kazuo , Gotoh Hiroshi , Kawakami Nobuyuki
Published: August 2007

It was demonstrated for the first time that the use of Al‐Ni alloy films and a‐Si surface nitridation for the direct contacts of interconnection lines with both ITO and a‐Si were feasible for the TFT technology. The mechanism how the direct contact, described in the present paper, works was studied using various analysis technique.
61.1: Motion‐Compensated Impulsive Driving Technique for LCD‐TV
Authors: Park Jae‐Hyeung , Kim Yun‐Jae , Park Minkyu , Amino Tadashi , Oh Jaeho , Kim Nam Deog , Kim Sang Soo
Published: August 2007

otion‐estimation/motion‐compensation (ME/MC) provides superior motion picture quality but its huge computation load results in high cost. Impulsive driving is a cost‐effective solution but it suffers from large flicker and brightness loss. Motion compensated impulsive driving technology has been developed to achieve high motion picture quality in a cost‐effective implementation by combining ME/MC and impulsive driving. The key idea is to apply ME/MC or impulsive driving selectively according to the motion vector distribution of the incoming image sequence. In this paper, the description of the algorithm and the experimental results are provided.
62.3: Doped Multilayer Polymer Cholesteric‐Liquid‐Crystal (PCLC) Flakes: A Novel Electro‐Optical Medium for Highly Reflective Color Flexible Displays
Authors: Marshall Kenneth L. , Hasman Katherine , Leitch Molly , Cox Gerald , Kosc Tanya Z. , Trajkovska‐Petkoska Anka , Jacobs Stephen D.
Published: August 2007

Polymer cholesteric‐liquid‐crystal (PCLC) flake/fluid‐host suspensions are a novel particle display technology for full‐color reflective display applications on rigid or flexible substrates. These “polarizing pigments” require no polarizers or color filters, switch rapidly at very low voltages, and produce highly saturated colors with a reflection efficiency approaching 80%.
62.4: Liquid‐Crystal Etalon Device for High‐Efficiency Field‐Sequential Display Enkh‐Amgalan Dorjgotov
Authors: Bos Philip J. , Bhowmik Achintya K.
Published: August 2007

We propose a pixel design using liquid crystal etalon device for high efficiency mobile field sequential color display. The new device is nearly loss‐less for monochromatic primary light sources. High efficiency transmittance is achieved through the use of a polarization insensitive, high transmittance etalon device which consists of dielectric mirrors on either side of a cavity filled with twisted nematic liquid crystal material. The device is simulated using numerical modeling program, and preliminary design results are presented.
63.2: Distinguished Paper: A Full‐Color, Top‐Emission AM‐OLED Display Driven by OTFTs
Authors: Yagi Iwao , Hirai Nobukazu , Noda Makoto , Imaoka Ayaka , Miyamoto Yoshihiro , Yoneya Nobuhide , Nomoto Kazumasa , Kasahara Jiro , Yumoto Akira , Urabe Tetsuo
Published: August 2007

We have developed an integration architecture for high‐resolution organic‐TFT (OTFT) arrays with top pixel electrodes on a plastic film. In this architecture, no damage isolation method of organic semiconductor (OSC) in a photolithographically defined resolution is employed. All the insulators in the backplane consist of organic polymers, enhancing both the mechanical flexibility of the backplane and the manufacturing throughput. These technologies have been successfully applied to produce a flexible, full‐color and top‐emission active‐matrix organic light‐emitting diode (AM‐OLED) display on a plastic substrate with a resolution of 80 ppi.
63.4L: Late News Paper: High Mobility Solution‐Processed Organic Thin‐Film Transistor Array for Active‐Matrix Color Liquid Crystal Displays
Authors: Kawasaki M. , Imazeki S. , Hirota S. , Arai T. , Shiba T. , Ando M. , Natsume Y. , Minakata T. , Uemura S. , Kamata T.
Published: August 2007

We have fabricated a solution‐processed 240 × 960 organic thin‐film transistor array to drive a liquid crystal display, where the semiconductor, gate dielectric and passivation films have been all formed using solution processes. A field effect mobility of 1.6 cm2/Vs obtained is the highest value for solution‐processed TFTs ever reported.
64.1: Invited Paper: Polarized OLEDS as Backlight for Liquid Crystal Displays
Authors: Culligan Sean W. , Chen Andrew C.‐A. , Wallace Jason U. , Tang Ching W. , Chen Shaw H.
Published: August 2007

This work aims at the design, synthesis, and characterization of novel conjugated glassy‐nematic liquid crystals for highly efficient and strongly polarized OLEDs. In addition to deep blue emission using oligofluorenes, emission of standard green, red, and white‐light has also been accomplished through chemical modification and physical doping.
65.1: Invited Paper: An Overview of Display Interconnect Technology Trends: Technologies & Markets
Authors: Opdahl Peter
Published: August 2007

This paper will address general technology and market trends for the assembly of display modules, concentrating on how the maturation of the display industry is affecting technology choices and market segmentation. The year 2007 promises to be one of great change in the world of flat panel displays, with non‐LCD technology getting its first real foothold in mobile phone main screen applications, a continuing glut of glass manufacturing capacity, and the migration of display assembly factories into Eastern Europe and Mexico. This, coupled with double‐digit percentage declines in the ASPs of almost every color display technology, means that manufacturers are continuing to squeeze out production costs wherever possible. As a result, companies are reviewing the back‐end interconnect assembly portion of display manufacturing in a way that they have not done before now. The long‐term end result is likely to be a higher level of segmentation in the display industry as it follows a path similar to the semiconductor industry before it. In the shorter term, companies will aggressively review technical requirements, assembly techniques, and material choices in their quest for lower costs.
67.1: Invited Paper: Hybrid Transflective Displays using Vertically Integrated Transparent OLED and Reflective LCD
Authors: Lee Jiun‐Haw , Xianyu Haiqing , Ge Zhibing , Zhu Xinyu , Lu Yen‐Hsun , Teng Chao‐Wen , Liu Kou‐Chen , Wu Shin‐Tson
Published: August 2007

We demonstrate a hybrid device by vertically integrating a reflective LCD and a transparent OLED. The vertical alignment (VA) LC cell operated at normally black (NB) mode is placed beneath the transparent OLED to improve device transmittance. Under dark ambient, OLED is the primary display but the NB‐RLCD absorbs the incoming light which in turn increases the ambient contrast ratio (A‐CR). However, it also absorbs the photons from the OLED emission and decreases the efficiency. In our hybrid device, by placing the transparent OLED on top of the reflective LCD, the transmittance of the hybrid device is enhanced by 57.3% due to the asymmetric emission intensities from both sides of the transparent OLED. Under bright ambient conditions, the OLED could be washed out but the RLCD is activated. Hence, the tandem display exhibits a high contrast ratio (>105:1) under any ambient light conditions.
68.2: 3.5 Inch QCIF+ AM‐OLED Panel Based on Oxide TFT Backplane
Authors: Lee Ho‐Nyun , Kyung Jaewoo , Kang Sun Kil , Kim Do Youl , Sung Myeon‐Chang , Kim Seong‐Joong , Kim Chang Nam , Kim Hong Gyu , Kim Sung‐tae
Published: August 2007

IGZO TFTs were fabricated on a glass substrate by conventional photo‐lithography and wet‐etching processes. The real mobility of our device was about 95 cm2/Vs and had very low dependence on the variation of W/L, channel length and channel width. An IGZO TFT array was also fabricated and a top emission OLED device was successfully driven by it. Therefore, the oxide TFT could be one of the promising candidates as a backplane for the OLED device.
68.3: Invited Paper: Transparent Amorphous Oxide Semiconductors for High Performance TFT
Authors: Hosono Hideo
Published: August 2007

This paper briefly describes unique electron transport properties of transparent amorphous oxide semiconductors (TAOS) for TFT performance along with our material design concept. Emphasized is essential importance of indium ion for emergence of high field effect mobility on the basis of recent results on electronic structure calculation on amorphous InGaZnO4.
69.3: Polymer/Metal‐Oxide Composite: A Novel Buffer Layer for Solution‐Processible OLEDs
Authors: Suzuki Tsunenori , Takasu Takako , Yamagata Sachiko , Seo Satoshi , Nomura Ryoji , Yamazaki Shunpei
Published: August 2007

We developed a novel polymer‐metal oxide composite which is suitable as a buffer layer for solution‐processible OLEDs. The composite, which consists of vanadium oxide and an amine‐containing polymer, was fabricated by a sol‐gel technique. It is possible to create Ohmic contact between the composite and electrodes, and this enabled the production of OLEDs with low driving voltage and high current efficiency.
16‐4: Development of Nano‐Sized Protective Layers for Flat Fluorescent Lamps (FFLs)
Authors: Jung K. T. , Evstropiev S. K. , Lee K. Y. , Lee K. S.
Published: August 2007

The preparation of different thin and uniform continuous oxide and mixed oxide‐fluoride coatings on the glass and on the surface of particulate layers (multi‐component phosphor layers; reflective layer; MgO layer) which layers are disposed inside lamp bulb, was studied. The use of simple and industrially available technique with acidic salt solutions provides the fabrication of these coatings. The effectiveness of the using of these coatings in FFL has been demonstrated.
Defining Spirituality and Giving Meaning to Occupation: The Perspective of Community-Dwelling Older Adults with Autonomy Loss
Authors: Griffith Jennifer , Caron Chantal D. , Desrosiers Johanne , Thibeault Rachel
Published: August 2007

Background. In the Canadian Model of Occupational Performance, meaningful occupation involves interaction between spirituality and environment. However little research exists on the process of giving meaning to occupation.Purpose. This study explored both meaningful occupation and the definition of spirituality from the perspective of community-dwelling older adults with autonomy loss.Method. Using a qualitative approach, grounded theory method of Glaser and Strauss (1967), eight cognitively intact persons were interviewed individually.Results. The process of giving meaning to occupation involves an intrinsic link between identity and meaningful occupation, with identity being central to the person. Following autonomy loss, a process of adjusting identity, involving social, psychological and spiritual aspects, occurs over time. Spirituality is defined in terms of its close links to religion and belief in a benevolent greater power.Implications of Research. This study contributes to the discussion of the concepts of spirituality, identity and meaning in occupational therapy.
Successful Participation: The Lived Experience among Children with Disabilities
Authors: Heah Tom , Case Tara , McGuire Brianna , Law Mary
Published: August 2007

Background. Children with disabilities are at risk for limited daily occupational participation. This paper presents a phenomenological study describing the meaning of participation in activities outside of school to children with physical and neurological disabilities and their parents. Methods. Semi-structured interviews were conducted with eight children and their parents. Results. Nine themes, organized under three categories, describe what successful participation means, and the personal and environmental supports and barriers to participation. Successful participation is defined in terms of being with others and being able to perform tasks independently. Conclusions. This study demonstrates that children with physical and neurological disabilities enjoy the same activities as those children without these disabilities. Activities allowing children to experience enjoyment have the best chance of ensuring children's participation. The role of the parent in providing opportunities for participation, and the importance of environmental and personal resources are particularly important. Finally, implications for occupational therapy and research are discussed.
Experiences of Social Class: Learning from Occupational Therapy Students
Authors: Beagan Brenda L.
Published: August 2007

Background and Purpose. Despite the potential in occupational therapy models, there has been little investigation of the ways social class may affect occupations or occupational therapy. This paper explores the occupational impacts of poverty. Methods. Essays by 17 occupational therapy students, who identify as lower class, were coded and analyzed inductively. Results. Class-based shame and stigma led to attempts to “pass” as middle class-an occupation consuming time and energy. Exclusion from middle-class leisure occupations left students with gaps in their adult knowledge. Family was a site of both shame and safety, as well as pressure to succeed. Educational occupations embody marginalization. Practice Implications. Class is not only about money, but also having the right norms, values, and experiences to fit easily in middle-class society. Educational and health care institutions epitomize middle-class assumptions. The experiences of these students may help therapists to examine where they unwittingly enact middle-class norms in practice.
Exploring Canadian Occupational Therapists' Understanding of and Experiences in Community Development
Authors: Lauckner Heidi , Pentland Wendy , Paterson Margo
Published: August 2007

Background. Occupational therapists are increasingly recognizing the importance of working with communities as a way to enhance health and well-being. Such work can occur through community development, a community-driven process in which communities are supported in identifying and addressing their health priorities. Purpose. This paper presents the qualitative findings of a study that explored the experiences of occupational therapists in Canada working in community development including how they understand community development and how they designed their role in this field. Methods. Occupational therapists working in community development shared their experiences and understanding of community development during 12 interviews. Results. The results of this study describe the iterative, reflexive process occupational therapists have undergone in coming to establish their role in this field. Implications. Recommendations are made regarding the preparation of future occupational therapists and for supporting those currently working in this field.
A Quantitative and Qualitative Investigation of Using Alice Programming to Improve Confidence, Enjoyment and Achievement among Non-Majors
Authors: Bishop-Clark Cathy , Courte Jill , Evans Donna , Howard Elizabeth V.
Published: August 2007

In this investigation, the use of the Alice programming language in an introductory computing class was studied from both a quantitative and qualitative perspective. Students in an introductory computing class participated in a 2.5–week unit to learn programming through the graphical programming environment of Alice. Quantitatively, students were surveyed before and after their Alice experience. One hundred and fifty-four students completed a short questionnaire about their enjoyment and confidence with computer programming along with a content test about their understanding of computer programming concepts. After the students completed a short tutorial on Alice and completed two short programming exercises, they completed the same questionnaire and content test. Qualitatively, three focus groups were held and students were asked to comment on their experience. Students were also required to write an essay requiring them to reflect on their Alice experiences. Data from student reflective essays were coded and analyzed Both the t-tests of the pre- and post-test survey data and the analysis of student essays show that students show significant increases in enjoyment of programming, confidence in programming, and understanding of programming concepts. Focus group comments provide additional insight to these findings.
Cephalometric Standards for Polish 10-Year-Olds with Normal Occlusion
Authors: Obloj Barbara , Fudalej Piotr , Dudkiewicz Zofia
Published: August 2007

Objective: To establish gender-specific normative data for Polish children at the age of 10 years.

Materials and Methods: Thirty-nine boys and 34 girls (mean age 10.37, SD = 0.52) of Polish ethnicity were selected based on the following criteria: Class I molar relationship, lack of crossbite or scissor-bite, positive overjet and overbite less than 5 mm, adequate amount of space in both dental arches, no visible asymmetry, and good facial proportions. Lateral cephalograms of each subject were scanned and analyzed with the use of NemoCeph NX2005 software. Descriptive statistics (mean and standard deviation) were calculated for all measured variables. Independent t-tests were performed to assess the intergender differences. The results were compared to the published norms of other white populations. Normative data were presented in the tables.

Results: Intergender differences included anterior cranial base length (sella-nasion), total and lower anterior facial height (nasion-menton and ANS-menton, respectively), posterior facial height (sella-gonion), SNA angle, point A to nasion perpendicular distance, pogonion to nasion perpendicular distance, and facial axis.

Conclusions: Polish 10-year-old boys had a larger anterior cranial base, and larger total anterior, lower anterior and posterior facial heights than girls. The maxillae and chin protrusion were more pronounced in girls.
Changes in Horizontal Jaw Position and Intraoral Pressure
Authors: Takada Jun-ichi , Ono Takashi , Takahashi Shigeki , Honda Ei-ichi , Kurabayashi Tohru
Published: August 2007

Objective: To determine the effect of an imbalance in buccolingual pressure that may be involved in molar dental compensation in the mandible and asymmetry of the dental arch in subjects with facial asymmetry.

Materials and Methods: We performed simultaneous measurement of the buccolingual pressure on the mandibular right first molar when subjects without facial asymmetry experimentally shifted the mandible laterally. Buccolingual pressures in the rest position (RP), right-shifted position (RS), and left-shifted position (LS) were compared. Moreover, T1-weighted magnetic resonance images were obtained in RP, RS, and LS.

Results: Tongue pressure tended to decrease in the order LS > RP > RS, while cheek pressure tended to increase in the order LS < RP < RS. The tongue/cheek pressure ratio tended to decrease in the order LS > RP > RS. There were significant positive (in RS) and negative (in LS) correlations between displacement of the tongue and tongue pressure.

Conclusions: This imbalance in buccolingual pressures in the laterally-shifted mandibular position may partly explain molar dental compensation in the mandible and asymmetry of the dental arch in subjects with facial asymmetry.
Diagnosis, Screening and Treatment of Root Resorption in Orthodontic Practices in Greece and Sweden
Authors: Makedonas Dimitrios , Hansen Ken
Published: August 2007

Objective: To evaluate the perception of Greek and Swedish orthodontic practitioners regarding the possible occurrence and prognosis of root resorption occurring during orthodontic treatment and to estimate practitioners' approaches to the diagnosis of preexisting root resorption, screening of prevalence, and treatment planning approach when moderate or severe root resorption is present.

Materials and Methods: Questionnaires were received from randomly selected Greek (n = 90) and Swedish (n = 106) practitioners. Topics of the questions included (a) the presence of history; (b) the radiographic evaluation of root resorption before, during, and after treatment; (c) the treatment approach of initial prevention and protocols in cases of radiographic diagnosis of root resorption during treatment.

Results: Of the respondents, 47.1% of the Swedish practitioners and 32.3% of the Greek practitioners use periapical and panoramic radiographs to diagnose root resorption, mostly in the anterior region. Both groups recognize trauma, root form, and oral habits as predisposing factors. The majority of Swedish orthodontists perform radiographic follow-up in the first 6 months. In contrast, the Greek orthodontists perform it at 1 year or at the end of treatment. The treatment approach for root resorption that is most frequently used by Swedish orthodontists is altering the treatment plan, using light forces, and allowing resting periods, while the Greek orthodontists most frequently use lighter forces and reduce the total duration of the treatment.

Conclusions: Because there is no specific approach offered in the literature, the prevention and treatment reassessment in cases of root resorption relies on individual practitioner perception.
Insertion Torque of Orthodontic Miniscrews According to Changes in Shape, Diameter and Length
Authors: Lim Seon-A. , Cha Jung-Yul , Hwang Chung-Ju
Published: August 2007

Objective: To determine the variation in the insertion torque of orthodontic miniscrews according to the screw length, diameter, and shape.

Materials and Methods: The maximum insertion torque (MIT) was measured using a torque tester at a constant speed of 3 rotations per minute. Cylindrical and taper type of miniscrews (Biomaterials Korea Inc, Seoul, Korea) with different lengths, diameters, and pitches were tested.

Results: The results showed that the insertion torque significantly increased with increasing screw length (P < .01). In particular, there was a significant increase in torque with increasing screw length and diameter (P < .01). An analysis of the serial insertion torque of miniscrews revealed the cylindrical type screw to have much higher insertion torque at the incomplete screw thread, while the taper type screw showed a much higher insertion torque at the final inclination part of the screw thread. The insertion torque was affected by the outer diameter, length, and shape in that order.

Conclusions: An increase in screw diameter can efficiently reinforce the initial stability of the miniscrew, but the proximity of the root at the implanted site should be considered.
Maxillary Protraction Appliance Effect on the Size of the Upper Airway Passage
Authors: Oktay Hüsamettin , Ulukaya Esengül
Published: August 2007

Objective: To test the hypothesis that maxillary protraction appliances (MPA) have no effect on the size of the upper airway passage and craniofacial structures in adolescent patients.

Materials and Methods: Twenty patients (5 male and 15 female; mean age 11.5 years) with skeletal Class III malocclusion were included in this study. The records of all patients who had maxillary protraction treatment and had lateral head radiographs taken before and after their protraction treatments were obtained from the files of treated cases. Treatment changes were determined by means of linear, angular, and area measurements. Data were analyzed statistically by means of paired t-test and correlation analysis.

Results: Significant increases were observed in the width and area of the pharyngeal airway. Significant increases also occurred in the sagittal growth of the maxilla, while a clockwise rotation and inhibition of sagittal growth were observed in the mandible.

Conclusions: The hypothesis was rejected. The size of the upper airway can be increased by means of MPA application.
Electronic and Steric Effects of Atropisomeric Ligands SYNPHOS® and DIFLUORPHOS®vs. BINAPs in Rh(I)‐Catalyzed Asymmetric Pauson–Khand Reaction
Authors: Kim Dong Eun , Choi Choong , Kim In Su , Jeulin Séverine , Ratovelomanana‐Vidal Virginie , Genêt Jean‐Pierre , Jeong Nakcheol
Published: August 2007

The electronic and steric effects of chiral biaryl diphosphine ligands on the Rh(I)‐catalyzed asymmetric Pauson–Khand type reaction were examined. We demonstrated that enantioselectivity and reaction yield were influenced by the electronic density on phosphorus, the dihedral angle of ligands and the electronic density of the alkyne substrate. Ligands bearing a narrower dihedral angle than Binap, such as Synphos (L4) and Difluorphos (L5), were found to increase substantially the enantioselectivity of the reaction, compared to Binap‐type ligands. Ligands having a deshielded phosphine, such as p‐CF3‐Binap (L3) and Difluorphos (L5) provided better enantioselectivity than Binap, with reduced formation of side products, especially with electron‐poor alkyne substrates.
Nitrogen Ligands in Copper‐Catalyzed Arylation of Phenols: Structure/Activity Relationships and Applications
Authors: Ouali Armelle , Spindler Jean‐Francis , Jutand Anny , Taillefer Marc
Published: August 2007

In spite of the importance of ligand/copper‐catalyzed arylations of nucleophiles in organic chemistry, the structural and electronic features that make a ligand efficient in these reactions have not been determined until now. In this work, several bidentate ligands involving pyridine and/or imine nitrogen binding sites such as our lead ligand 1 have been synthesized, and tested in phenol arylations with a view to highlight relationships between the structure of the chelates and their efficacy. This study allowed us to more precisely define the role of each type of N‐binding site during the catalytic process, and to discover new efficient ligands. Among them, the iminopyridine 6a, which is cheap and easy‐to‐prepare in high yield, is very attractive for industrial applications. Some examples of its field of application are presented here. In the future, the development of this work could allow a more rational design of efficient ligands in arylation reactions, without resorting to classical ligand screening.
New C2‐Symmetric Diphosphite Ligands Derived from Carbohydrates: Effect of the Remote Stereocenters on Asymmetric Catalysis
Authors: Axet M. Rosa , Benet‐Buchholz Jordi , Claver Carmen , Castillón Sergio
Published: August 2007

The synthesis of new modular chiral diphosphite ligands with C2‐symmetry and carbohydrate backbone is reported. We also report here the synthesis of the corresponding rhodium complexes [Rh(COD)(L)]BF4 (L=diphosphite). All these species have been characterised in solution by NMR spectroscopy and in some cases in the solid state by X‐ray diffraction. The solution structures of the hydridorhodiumcarbonyl species [RhH(CO)2(L)], where L=diphosphites 12a–14a, 12b, have been studied using high‐pressure NMR spectroscopy. The configuration and substitution of the remote stereocentres in positions 2 and 5 of the tetrahydrofuran ring of the diphosphite ligands were observed to have a considerable influence on the results obtained in the rhodium‐catalysed hydroformylation and hydrogenation reactions. Thus, the configuration of the major isomer obtained in the hydroformylation reaction may be controlled by changing the configuration of these stereocentres.
Second Generation Artificial Hydrogenases Based on the Biotin‐Avidin Technology: Improving Activity, Stability and Selectivity by Introduction of Enantiopure Amino Acid Spacers
Authors: Rusbandi Untung E. , Lo Cheikh , Skander Myriem , Ivanova Anita , Creus Marc , Humbert Nicolas , Ward Thomas R.
Published: August 2007

We report on our efforts to create efficient artificial metalloenzymes for the enantioselective hydrogenation of N‐protected dehydroamino acids using either avidin or streptavidin as host proteins. Introduction of chiral amino acid spacers – phenylalanine or proline – between the biotin anchor and the flexible aminodiphosphine moiety 1, combined with saturation mutagenesis at position S112X of streptavidin, affords second generation artificial hydrogenases displaying improved organic solvent tolerance, reaction rates (3‐fold) and (S)‐selectivities (up to 95 % ee for N‐acetamidoalanine and N‐acetamidophenylalanine). It is shown that these artificial metalloenzymes follow Michaelis–Menten kinetics with an increased affinity for the substrate and a higher kcat than the protein‐free catalyst (compare kcat 3.06 min−1 and KM 7.38 mM for [Rh(COD)Biot‐1]+ with kcat 12.30 min−1 and KM 4.36 mM for [Rh(COD)Biot‐(R)‐Pro‐1]+ ⊂ WT Sav). Finally, we present a straightforward protocol using Biotin‐Sepharose to immobilize artificial metalloenzymes (>92 % ee for N‐acetamidoalanine and N‐acetamidophenylalanine using [Rh(COD)Biot‐(R)‐Pro‐1]+ ⊂ Sav S112W).
Synthesis of Hexahydrocyclopenta[c]furans by an Intramolecular Iron‐Catalyzed Ring Expansion Reaction
Authors: Hilt Gerhard , Bolze Patrick , Heitbaum Maja , Hasse Katrin , Harms Klaus , Massa Werner
Published: August 2007

The intramolecular iron‐catalyzed ring expansion reaction of epoxyalkenes was investigated with a preformed iron(salen) [Fe(Salen)] complex. The formal insertion of the alkene into the epoxide generated hexahydrocyclopenta[c]furan derivatives in moderate to good yields and diastereoselectivities depending on other functional groups present in the starting materials. In addition, oxygen‐tethered epoxyalkenes were used for the synthesis of lignan isomers. The scope and limitations of the Fe(Salen)‐catalyzed process of the reaction are discussed.
Palladium‐Catalyzed Regioselective Cross‐Coupling Reactions of 3‐Bromo‐4‐tosyloxyquinolin‐2(1H)‐one with Arylboronic Acids. A Facile and Convenient Route to 3,4‐Disubstituted Quinolin‐2(1H)‐ones
Authors: Wang Zhiyong , Fan Renhua , Wu Jie
Published: August 2007

The palladium‐catalyzed regioselective cross‐coupling reaction of 3‐bromo‐4‐tosyloxyquinolin‐2(1H)‐one with arylboronic acid is described, which provides a simple, general, efficient, and practical route for the synthesis of 3,4‐disubstituted quinolin‐2(1H)‐ones.
Substituted Benzocarbocycles by Palladium‐Catalyzed Cascade Reactions Featuring a C(sp3)H Activation Step
Authors: Hitce Julien , Baudoin Olivier
Published: August 2007

Valuable 4‐ and 5‐membered benzocarbocycles were synthesized via selective palladium‐catalyzed cascade reactions which combined C(sp3)H activation, Heck cyclization, Heck arylation or olefin hydrogenation. In all cases, all mechanistically independent steps were catalyzed by a single multi‐functional catalyst.
An Improved Protocol for the Direct Asymmetric Aldol Reaction in Ionic Liquids, Catalysed by Onium Ion‐Tagged Prolines
Authors: Lombardo Marco , Pasi Filippo , Easwar Srinivasan , Trombini Claudio
Published: August 2007

Two onium ion‐tagged prolines, imidazolium bis(trifluoromethylsulfonyl)imide‐substituted proline 6 and butyldimethylammonium bis(trifluoromethylsulfonyl)imide‐substituted proline 7, were synthesised and their catalytic activity in the direct asymmetric aldol condensation was studied in ionic liquids. For the reaction of acetone with various aldehydes, using 5 % of the catalyst, the yields of the aldols varied between 50–85 % while the ee values were in the 80–85 % range. Other ketones were studied too, the yields obtained in those cases being in the 35–78 % range while the enantioselectivities varied between 75–94 %.
Chiral Phosphoric Acid‐Catalyzed Enantioselective Aza‐Friedel–Crafts Reaction of Indoles
Authors: Terada Masahiro , Yokoyama Shigeko , Sorimachi Keiichi , Uraguchi Daisuke
Published: August 2007

A highly enantioselective 1,2‐aza‐Friedel–Crafts reaction of N‐tert‐butyldimethylsilylindole with N‐tert‐butoxycarbonyl aromatic imines is demonstrated using a BINOL‐derived monophosphoric acid catalyst. The present approach provides efficient access to 3‐indolylmethaneamines with aryl substituents in excellent enantioselectivities (up to 98 % ee). An inversion in the sense of enantioselection was found between monophosphoric acid catalysts bearing different substituents introduced at the 3,3′‐position of binaphthyl backbone. We also calculated the three‐dimensional structure of the monophosphoric acid catalysts to speculate on the inversion of the stereochemical outcome.
Olefin Metathesis of Amine‐Containing Systems: Beyond the Current Consensus
Authors: Compain Philippe
Published: August 2007

Olefin metathesis is one of the most powerful synthetic tool to access amine‐containing heterocycles and alkaloids. A major drawback associated with the use of amines concerns their ability to coordinate to metal‐alkylidene complexes and to interfere unproductively with catalytic activity. Based on literature precedents, it has been established as a “dogma” that efficient metathesis reactions are suppressed in the presence of basic amines and that such substrates must invariably be deactivated by conversion of the amines to the corresponding carbamates or ammonium salts. However, an increasing number of examples of amine‐containing compounds that are good substrates for metathesis is being reported in the literature. How can this “non‐classical” reactivity be rationalized and exploited? The purpose of this review is to provide an overview of successful metathesis reactions performed with amine‐containing compounds in order to allow some guidelines to be formulated. A special emphasis is placed on the different parameters that may influence the outcome of the reaction such as steric effects, amine basicity, and the nature of the catalyst.
Triphasic Liquid Systems for Improved Separations. Trioctylmethylammonium Chloride‐Immobilised Rhodium Trichloride: A Phosphine‐Free Hydroformylation Catalytic System
Authors: Paganelli Stefano , Perosa Alvise , Selva Maurizio
Published: August 2007

A liquid triphasic system made of isooctane, water, and trioctylmethylammonium chloride allows one to carry out the hydroformylation of model olefins using neat RhCl3 as catalyst precursor. By using the triphasic system, the catalyst is kept separate from the reagents and products. This allows one to simply remove the product and to recycle the catalyst numerous times. No leaching of rhodium into the organic phase is observed.
Evaluation of opioid induced nausea and vomiting in sickle cell disease
Authors: Shord Stacy Shifflett , Chew Lita , Villano John
Published: August 2007

A common side effect of opioids is nausea and vomiting; however, the incidence in hospitalized patients receiving opioids for acute pain is unknown. We performed a retrospective study in adult patients with sickle cell disease admitted for an acute pain crisis during a six‐month period to evaluate the incidence of nausea and vomiting and characterize the prescribing of antiemetics. Eligibility included normal hepatic and renal function. Thirty‐four subjects with a total of 97 admissions were evaluated. As expected, opioids were prescribed during all admissions. Fifty percent of the subjects experienced nausea or vomiting during the study period and these same patients accounted for the majority of the admissions, 17 subjects with 71 admissions (Group I). Nausea was reported in 18 (25%) of these admissions and vomiting was reported in 24 (34%) of these admissions. The most common antiemetics prescribed were: prochlorperazine, metoclopramide, and promethazine and antiemetics were ordered during 22 (23%) separate admissions for all subjects included in the study. The clinical benefit of these medications is limited due to uneven documentation. In conclusion, many of our patients experienced nausea or vomiting with antiemetics infrequently prescribed on an as needed basis. This suggests a need for better approaches to manage nausea and vomiting in patients receiving opioids. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Daily differences in patterns of physical activity among overweight/obese children engaged in a physical activity program
Authors: Aires Luísa , Santos Rute , Silva Pedro , Santos Paula , Oliveira José , Ribeiro José C. , Rego Carla , Mota Jorge
Published: August 2007

The aim of this study was to compare the physical activity of overweight/obese children during days when they attended a physical activity program, and days when they did not. This is a cross‐sectional intervention study of daily physical activity. The participants were referred by family, doctors, or hospital pediatricians to take part in a 10‐month interdisciplinary, outpatient obesity intervention program for children. The subjects included 41 overweight and obese children aged 8–16 years, 19 boys (46%) and 22 girls (54%); BMI: 25.7 + 3.3 kg m−2. The MTI Actigraph was used as an objective measure of daily physical activity over seven consecutive days. Physical activity program days presented a significantly higher percentage of time (4.68%) spent in moderate‐to‐vigorous activity compared with no physical activity program days (3.16%) and weekend (2.7%). The results of this study suggest that a physical activity program can help increasing daily physical activity in obese children, with a special focus on MVPA level. Our data point that obese children are less active at weekend than during weekdays. Am. J. Hum. Biol., 2007. © 2007 Wiley‐Liss, Inc.
Social inequality in premature mortality among polish urban adults during economic transition
Authors: Kołodziej Halina , Łopuszańska Monika , Bielicki Tadeusz , Jankowska Ewa Anita
Published: August 2007

Rates of premature mortality among adults are important measures of the economic and psychosocial well‐being of human populations. In many countries, such rates are, as a rule, inversely related to the level of attained education. We examined changes in educational group‐specific mortality rates among urban adults in Poland during the country's rapid transition in the 1990s from a socialist command economy to a free market system. Two census‐based analyses of individual death records of urban dwellers aged 35–64 years were compared. We utilized all records of death, which occurred during the 2‐year periods 1988–89 and 2001–02. Population denominators were taken from the censuses of 1988 and 2002. The age‐specific mortality rates were used to evaluate absolute differences in mortality. To assess relative differences between educational levels, mortality rate ratios (MRRs) with 95% CI (confidence interval) were calculated using Poisson regression. A regular educational gradient in mortality persisted in each 10‐year age group throughout the period covered by our data. Moreover, age‐specific mortality rates declined steadily in all educational groups, and this decline was most marked in the two oldest age groups (45–54 and 55–64 years). The trend was accompanied by widening of educational differences in mortality as expressed by MRRs. Systemic political transformation in Poland has brought a mixture of beneficial and detrimental effects on the well‐being of society. With regard to the changes in rates of premature mortality among adults, the benefits have prevailed, although individuals with the lowest educational level benefited less than those with the highest education. Am. J. Hum. Biol., 2007. © 2007 Wiley‐Liss, Inc.
Spermiogenesis in Soft‐Shelled Turtle, Pelodiscus sinensis
Authors: Zhang Li , Han Xiang‐Kun , Li Mei‐Ying , Bao Hui‐Jun , Chen Qiu‐Sheng
Published: August 2007

Spermiogenesis in the soft‐shelled turtle, Pelodiscus sinensis, was examined by transmission electron microscopy. The process includes nuclear elongation, chromatin condensation, acrosomal and flagellar development, and elimination of excess cytoplasm. In stage I, the proacrosomal vesicle occurs next to a shallow fossa of the nucleus, and a dense acrosomal granule forms beneath it. A smaller subacrosomal granule in the middle of the fibrous layer is related to the development of intranuclear tubules. The nucleus begins to move eccentrically. In stage II, the round proacrosomal vesicle is flattened by protrusion of the nuclear fossa, and the dense acrosomal granule diffuses into the vesicle, as the fibrous layer forms the subacrosomal cone. Circular manchettes develop around the nucleus, and the chromatin coagulates into small granules. The movement of the nucleus causes rearrangement of the cytoplasm. In stage III, the front of the elongating nucleus protrudes out of the spermatid and is covered by the flat acrosome; coarse granules replace the small ones within the nucleus. At the posterior pole of the head, mitochondria move backward. Numerous microtubules begin to assemble the axoneme of flagellum. In stage IV, the chromatin concentrates to dense homogeneous phase. The circular manchette is reorganized longitudinally. The Sertoli process covers the acrosome and the residues of the cytoplasmic lobes are eliminated. In stage V, the sperm head matures. After dissolution of the longitudinal manchette, the mitochondria arrange themselves around the proximal and distal centrioles. Caudal to the mitochondrial mass, a fibrous sheath surrounds the proximal portion of the flagellum. Anat Rec, 290:1213‐1222, 2007. © 2007 Wiley‐Liss, Inc.
Ermüdungsbeanspruchungen von Betonbrücken unter zunehmendem Schwerverkehr
Authors: Grünberg Jürgen , Hansen Michael , Liebig Jan Peter
Published: August 2007

Der erwartete Anstieg des Schwerverkehraufkommens führt zu größeren Ermüdungsbeanspruchungen an Brückentragwerken. Dabei sind die Auswirkungen in Längsrichtung der Brücken abhängig von dem Lastmodellgewicht und dem Verhältnis zwischen der Lastmodelllänge und der Tragwerkstützweite. Das Institut für Massivbau der Leibniz Universität Hannover hat im Auftrag des Bundesministers für Verkehr, Bau und Stadtentwicklung (BMVBS) ein Forschungsvorhaben durchgeführt, in dem Brückentragwerke aus Beton mit verschiedenen Querschnittsausbildungen (Kastenträger, schiefwinklige Platte, zweistegiger Plattenbalken) im Hinblick auf ihren Ermüdungswiderstand analysiert worden sind. Die Beanspruchungen für den Beton und den Bewehrungsstahl sind mit aufwändigen numerischen Modellen in Längs‐ und Quertragrichtung der Brücken ermittelt worden. Neben den Einwirkungskombinationen nach DIN‐Fachbericht für die Nachweise der Ermüdungsbeanspruchungen wurden auch die Beanspruchungen infolge der 60 t‐Fahrzeugkombination nach dem modularen Nutzfahrzeugkonzept bestimmt, um die zukünftige Entwicklung des Schwerlastverkehrs einzubeziehen.
Sicherheitskonzept von unterspannten Konstruktionen
Authors: Ploch Jan , Novák Balthasar
Published: August 2007

Ständige Einwirkungen und Vorspannung werden in den Regelwerken als unabhängige Einwirkungen behandelt und mit unterschiedlichen (Teil‐)Sicherheitsbeiwerten versehen. Dem gegenüber gibt es Vorschläge, bei Tragwerken, deren Geometrie während des Vorspannens kontrolliert wird, Eigenlasten und Vorspannung als gemeinsamen Lastfall “ständige Einwirkungen” anzusehen und somit denselben Sicherheitsbeiwert auf sie anzuwenden. Diese beiden Ansätze werden systematisch hinsichtlich der Sicherheit der Tragwerke verglichen. Es wird gezeigt, dass die Auffassung von Eigenlasten und Vorspannung als gemeinsamer Lastfall nicht zu einem ausreichenden Sicherheitsniveau führt. Aus den Ergebnissen der Untersuchungen wird ein Vorschlag entwickelt, der den Einfluss von Geometriekontrollen während des Vorspannens durch Modifikation des Teilsicherheitsbeiwerts für die Vorspannung berücksichtigt und zum geforderten Zuverlässigkeitsniveau bei gleichzeitig wirtschaftlicheren Dimensionierungen führt.
Neue Sichtbetontechnologie im Praxistest an einer 12 Meter hohen Wand
Authors: Lohaus Ludger , Fischer Karen , Gläser Thomas , Fuchs Andreas
Published: August 2007

Am Institut für Baustoffe der Leibniz Universität Hannover wurden mit Hilfe von zwei Prüfschalungen neue betontechnologische Ansätze für robuste Sichtbetonzusammensetzungen entwickelt. Da das Verhalten dieser sehr weichen bis fließfähigen Frischbetone von herkömmlichen Rüttelbetonen abweicht, wird ein Weg zur Umsetzung der neuen Sichtbetontechnologie in die Praxis vorgeschlagen. Beim Betonieren einer rund 12 Meter hohen Sichtbetonwand beim Neubau eines Wissenschaftszentrums im Kompetenzzentrum für nachwachsende Rohstoffe in Straubing ist ein erster Praxistest gelungen. Hierbei führten die Ansätze der neuen Sichtbetontechnologie im Zusammenspiel mit der Nutzung von Sichtbetonprüfschalungen sowie der Herstellung von Erprobungsflächen zu einem guten Gesamtergebnis der unter schwierigen Betonierbedingungen erstellten Sichtbetonwand.
Optimal Response‐Adaptive Designs for Continuous Responses in Phase III Trials
Authors: Biswas Atanu , Bhattachary Rahul , Zhang Lanju
Published: August 2007

Optimal response‐adaptive designs in phase III clinical trial set up are gaining more interest. Most of the available designs are not based on any optimal consideration. An optimal design for binary responses is given by Rosenberger et al. (2001) and one for continuous responses is provided by Biswas and Mandal (2004). Recently, Zhang and Rosenberger (2006) proposed another design for normal responses. This paper illustrates that the Zhang and Rosenberger (2006) design is not suitable for normally distributed responses, in general. The approach cannot be extended for other continuous response cases, such as exponential or gamma. In this paper, we first describe when the optimal design of Zhang and Rosenberger (2006) fails. We then suggest the appropriate adjustments for designs in different continuous distributions. A unified framework to find optimal response‐adaptive designs for two competing treatments is proposed. The proposed methods are illustrated using some real data. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Maternity Length of Stay Modelling by Gamma Mixture Regression with Random Effects
Authors: Lee Andy H. , Wang Kui , Yau Kelvin K. W. , McLachlan Geoffrey J. , Ng Shu Kay
Published: August 2007

Maternity length of stay (LOS) is an important measure of hospital activity, but its empirical distribution is often positively skewed. A two‐component gamma mixture regression model has been proposed to analyze the heterogeneous maternity LOS. The problem is that observations collected from the same hospital are often correlated, which can lead to spurious associations and misleading inferences. To account for the inherent correlation, random effects are incorporated within the linear predictors of the two‐component gamma mixture regression model. An EM algorithm is developed for the residual maximum quasi‐likelihood estimation of the regression coefficients and variance component parameters. The approach enables the correct identification and assessment of risk factors affecting the short‐stay and long‐stay patient subgroups. In addition, the predicted random effects can provide information on the inter‐hospital variations after adjustment for patient characteristics and health provision factors. A simulation study shows that the estimators obtained via the EM algorithm perform well in all the settings considered. Application to a set of maternity LOS data for women having obstetrical delivery with multiple complicating diagnoses is illustrated. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)