bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparison of Site Response Techniques Using Weak-Motion Earthquakes and Microtremors
Authors: Molnar Sheri , Cassidy John F.
Published: March 2006

The applicability of the microtremor spectral ratio method is examined by comparing microtremor and weak-motion earthquake site responses at seven permanent strong-motion sites in Victoria, British Columbia. For each site, a weak-motion earthquake standard spectral ratio (bedrock reference), the average horizontal-to-vertical spectral ratio of up to five weak-motion earthquakes, and the average microtremor (Nakamura method) spectral ratio are compared. The geologic setting of Victoria is ideal for site response studies with a near-surface high impedance contrast between thin geologic layers of Victoria clay (about 11 m maximum in this study) and Pleistocene till or bedrock. Regardless of excitation source (weak-motion earthquakes or microtremors) and spectral ratio method, similar peak amplitudes and fundamental frequencies were found. Thicker material (>10 m) sites displayed higher peak amplitudes (up to six times amplification) at frequencies of 2–5 Hz compared to sites with a thin lens of material (<3 m) over bedrock that showed peak amplitudes at frequencies of >8 Hz.
Cost-Effectiveness of Stronger Woodframe Buildings
Authors: Porter Keith A. , Scawthorn Charles R. , Beck James L.
Published: March 2006

We examine the cost-effectiveness of improvements in woodframe buildings. These include retrofits, redesign measures, and improved quality in 19 hypothetical woodframe dwellings. We estimated cost-effectiveness for each improvement and each zip code in California. The dwellings were designed under the CUREE-Caltech Woodframe Project. Costs and seismic vulnerability were determined on a component-by-component basis using the Assembly Based Vulnerability method, within a nonlinear time-history structural-analysis framework and using full-size test specimen data. Probabilistic site hazard was calculated by zip code, considering site soil classification, and integrated with vulnerability to determine expected annualized repair cost. The approach provides insight into uncertainty of loss at varying shaking levels. We calculated present value of benefit to determine cost-effectiveness in terms of benefit-cost ratio (BCR). We find that one retrofit exhibits BCRs as high as 8, and is in excess of 1 in half of California zip codes. Four retrofit or redesign measures are cost-effective in at least some locations. Higher quality is estimated to save thousands of dollars per house. Results are illustrated by maps for the Los Angeles and San Francisco regions and are available for every zip code in California.
Fragility Functions for Older Reinforced Concrete Beam-Column Joints
Authors: Pagni Catherine A. , Lowes Laura N.
Published: March 2006

Fragility functions are developed to predict the method of repair required for older reinforced concrete beam-column joints damaged due to earthquake loading. The results of previous experimental studies are used to develop empirical relationships between damage states and engineering demand parameters, such as interstory drift, joint deformation, and number of load cycles. Damage states are proposed and linked deterministically with commonly employed methods of repair; these damage states are characterized by parameters such as concrete crack width, extent of concrete spalling, and yielding and buckling of reinforcement. Probability distributions are fit to the empirical data and evaluated using standard statistical methods. The results of this effort are families of fragility functions that predict the required method of repair for a damaged joint.
Effect of Modifying Bearing Fixities on the Seismic Response of Short- to Medium-Length Bridges with Heavy Substructures
Authors: Hindi Riyadh , Dicleli Murat
Published: March 2006

The effect of modifying the fixity conditions of the bearings on the seismic response and vulnerability of existing bridges with heavy substructures is studied. For this purpose, nonlinear seismic analysis of a typical bridge with heavy substructures is conducted to assess its seismic response and vulnerabilities. Next, the bearings are modified to obtain four different configurations of bearing fixities over the substructures. Nonlinear seismic analyses of the bridge are conducted to assess its seismic response and vulnerability for each bearing fixity configuration. It is found that changing the fixities of the bearings may be an effective response modification technique to mitigate the effect of seismic forces on vulnerable substructures of the bridge under consideration. The thermal load effects on the bridge with fixed bearings are found to be generally negligible compared to seismic load effects. Thus such a response modification technique may be used for the economical design of new or seismic retrofitting of existing short- to medium-length bridges similar to that considered in this study and subjected to low- to moderate-intensity ground motions.
Management of Venous Thromboembolism in Patients With Primary and Metastatic Brain Tumors
Authors: Gerber David E. , Grossman Stuart A. , Streiff Michael B.
Published: March 2006

Venous thromboembolism occurs commonly throughout the clinical course of patients with brain tumors. A number of hemostatic and clinical factors contribute to this hypercoagulable state. Concern over the possibility of intracranial bleeding has limited the use of anticoagulation in this population. However, mechanical approaches such as vena cava filters have high complication and treatment failure rates in patients with intracranial malignancies. In addition, the available data suggest that anticoagulation can be used safely and effectively in most of these patients. Patients with thrombocytopenia, recent neurosurgery, and tumor types prone to bleeding require special consideration. When intracranial hemorrhage does occur, it is often due to overanticoagulation, requiring prompt anticoagulation reversal and neurosurgical consultation.
Physiologic and Metabolic Magnetic Resonance Imaging in Gliomas
Authors: Cao Yue , Sundgren Pia C. , Tsien Christina I. , Chenevert Thomas T. , Junck Larry
Published: March 2006

Magnetic resonance (MR) imaging provides excellent soft tissue differentiation and in vivo assessment of physiologic and metabolic properties of tissue. As new and more aggressive treatment modalities and combined modalities are being investigated for brain tumor treatment, it is becoming more important to accurately define tumor volumes for treatment planning, to determine the most aggressive tumor regions for intensified radiation treatment, to identify early regional response to therapy for reoptimization of treatment, and to detect early indicators of developing normal tissue toxicity. Readily available MR techniques of physiologic and metabolic imaging can currently provide useful information regarding tumor tissue properties including chemical composition, cerebral blood volume, perfusion, vascular permeability, and water mobility. This article will focus on the potential value of MR physiologic and metabolic imaging in the clinical management of malignant gliomas.
Diagnosis and Treatment of Recurrent High-Grade Astrocytoma
Authors: Butowski Nicholas A. , Sneed Patricia K. , Chang Susan M.
Published: March 2006

High-grade gliomas represent a significant source of cancer-related death, and usually recur despite treatment. In this analysis of current brain tumor medicine, we review diagnosis, standard treatment, and emerging therapies for recurrent astrocytomas. Difficulties in interpreting radiographic evidence, especially with regard to differentiating between tumor and necrosis, present a formidable challenge. The most accurate diagnoses come from tissue confirmation of recurrent tumor, but a combination of imaging techniques, such as magnetic resonance spectroscopy imaging, may also be relevant for diagnosis. Repeat resection can prolong life, but repeat irradiation of the brain poses serious risks and results in necrosis of healthy brain tissue; therefore, reirradiation is usually not offered to patients with recurrent tumors. We describe the use of conventional radiotherapy, intensity-modulated radiotherapy, brachytherapy, radiosurgery, and photodynamic therapy for recurrent high-grade glioma. The use of chemotherapy is limited by drug distribution and toxicity, but the development of new drug-delivery techniques such as convection-enhanced delivery, which delivers therapeutic molecules at an effective concentration directly to the brain, may provide a way to reduce systemic exposure to cytotoxic agents. We also discuss targeted therapies designed to inhibit aberrant cell-signaling pathways, as well as new experimental therapies such as immunotherapy. The treatment of this devastating disease has so far been met with limited success, but emerging knowledge of neuroscience and the development of novel therapeutic agents will likely give patients new options and require the neuro-oncology community to redefine clinical trial design and strategy continually.
Primary CNS Lymphoma
Authors: Batchelor Tracy , Loeffler Jay S.
Published: March 2006

Primary CNS lymphoma (PCNSL), an uncommon form of extranodal non-Hodgkin's lymphoma (NHL), has increased in incidence during the last three decades and occurs in both immunocompromised and immunocompetent hosts. PCNSL in immunocompetent patients is associated with unique diagnostic, prognostic, and therapeutic issues, and the management of this malignancy is different from that of other forms of extranodal NHL. Characteristic imaging features should be suggestive of the diagnosis, avoidance of corticosteroids, if possible, and early neurosurgical consultation for stereotactic biopsy. Because PCNSL may involve the brain, CSF, and eyes, diagnostic evaluation should include assessment of all of these regions as well as screening for possible occult systemic disease. Resection provides no therapeutic benefit and should be reserved for the rare patient with neurologic deterioration due to brain herniation. Whole-brain radiation therapy (WBRT) alone is insufficient for durable tumor control and is associated with a high risk of neurotoxicity in patients older than age 60. Neurotoxicity typically is associated with significant cognitive, motor, and autonomic dysfunction, and has a negative impact on quality of life. Chemotherapy and WBRT together improve tumor response rates and survival compared with WBRT alone. Methotrexate-based multiagent chemotherapy without WBRT is associated with similar tumor response rates and survival compared with regimens that include WBRT, although controlled trials have not been performed. The risk of neurotoxicity is lower in patients treated with chemotherapy alone.
Current Strategies in Treatment of Oligodendroglioma: Evolution of Molecular Signatures of Response
Authors: Jaeckle Kurt A. , Ballman Karla V. , Rao Ravi D. , Jenkins Robert B. , Buckner Jan C.
Published: March 2006

Oligodendroglioma frequently (≥ 70%) responds to radiation and chemotherapy, and is the first CNS neoplasm in which a genetic signature (1p and 19q deletion) has been associated with outcome within the context of large clinical trials. Current translational investigations focus on deletions or mutations of potential tumor suppressor genes, epigenetic alterations, amplification or mutation of growth factor and regulatory genes, and characterization of signaling events and regulatory protein expression. The most compelling data has involved 1p and 19q loss, which is observed in over 50% of anaplastic oligodendrogliomas. In two randomized phase III trials (Radiation Therapy Oncology Group 9402 and European Organisation for Research and Treatment of Cancer 26951), the addition of neoadjuvant or adjuvant procarbazine, lomustine, and vincristine (PCV; respectively) to radiotherapy did not produce superior survival as compared with radiotherapy alone. A modest increase in progression-free survival was observed with the addition of PCV, but at the cost of increased toxicity. Combined 1p and 19q loss identified a favorable prognostic group in both studies, which appeared to be independent of treatment arms. However, it is unclear whether these deletions represent surrogate markers of a favorable biologic tumor behavior, or are predictive of outcome after specific treatment. Currently, there is insufficient data to allow therapeutic decisions to be made solely on the basis of 1p and 19q gene deletion status. Future phase III trials are evaluating other chemotherapeutic and targeted agents, including temozolomide, and include correlative investigations of aberrant molecular events in these neoplasms, which may lead to future therapeutic strategies that are based on specific molecular signatures.
Diffusely Infiltrative Low-Grade Gliomas in Adults
Authors: Lang Frederick F. , Gilbert Mark R.
Published: March 2006

Diffusely infiltrating low-grade gliomas (LGGs) include astrocytomas, oligodendrogliomas, and mixed oligoastrocytomas (WHO grade 2). Due to the routine use of magnetic resonance imaging, there is an increasing need to formulate treatment guidelines for patients with LGGs. However, there is little consensus about the optimal treatment strategy for diffusely infiltrative LGGs, and the clinical management of LGGs is one of the most controversial areas in neurooncology. Although the standard of care has not been established, several randomized trials are beginning to provide some answers. Furthermore, laboratory correlative studies are defining subsets of LGG that may identify patients with better prognoses and increased chance of responding to therapy. This article reviews the most recent data regarding the treatment of LGG, emphasizing evidenced based approaches from current clinical trials.
Varp is a Rab21 guanine nucleotide exchange factor and regulates endosome dynamics
Authors: Zhang Xinjun , He Xi , Fu Xin-Yuan , Chang Zhijie
Published: March 2006

The small GTPases Rab5 and Rab21 are closely related, and play essential roles in endocytic trafficking. Rab5 is regulated by VPS9-domain-containing guanine nucleotide exchange factors. Here, we describe a new VPS9-domain protein with ankyrin repeats, the VPS9-ankyrin-repeat protein (Varp). Varp interacts preferentially with GDP-bound Rab21 and has a much stronger guanine nucleotide exchange activity towards Rab21 than Rab5. Furthermore, RNAi-mediated depletion of endogenous Varp significantly disrupts the activity of Rab21 in HeLa cells. Ectopically expressed Varp mainly localizes to early endosomes and causes enlargement of early endosomes and giant late endosomes. Both the VPS9 domain and ankyrin-repeats are required for the endosomal localization and the activity of Varp in vivo. These results suggest that Varp is a potential Rab21 guanine nucleotide exchange factor and might regulate endosome dynamics in vivo.
ER-bound PTP1B is targeted to newly forming cell-matrix adhesions
Authors: Hernández Mariana V. , Sala Maria G. Davies , Balsamo Janne , Lilien Jack , Arregui Carlos O.
Published: March 2006

Here, we define the mechanism through which protein tyrosine phosphatase 1B (PTP1B) is targeted to cell-matrix adhesion sites. Green fluorescent protein (GFP)-labeled PTP1B bearing the substrate-trapping mutation D181A was found in punctate structures in lamellae. The puncta co-localized with focal adhesion kinase (FAK) and Src, and defined the distal tips of cell-matrix adhesion sites identified with paxillin and vinculin. PTP1B is largely associated with the external face of the endoplasmic reticulum (ER) and the puncta develop from ER projections over cell-matrix adhesion sites, a process dependent on microtubules. Deletion of the ER-targeting sequence resulted in cytosolic localization and altered the distribution of PTP1B at cell-matrix foci, whereas mutations disrupting interactions with Src homology 3 (SH3) domains, and the insulin and cadherin receptors had no effect. PTP1B recognizes substrates within forming adhesion foci as revealed by its preferential association with paxillin as opposed to zyxin-containing foci. Our results suggest that PTP1B targets to immature cell-matrix foci in newly forming lamellae by dynamic extensions of the ER and contributes to the maturation of these sites.
The plasma membrane recycling pathway and cell polarity in plants: studies on PIN proteins
Authors: Boutté Yohann , Crosnier Marie-Thérèse , Carraro Nicola , Traas Jan , Satiat-Jeunemaitre Béatrice
Published: March 2006

The PIN-FORMED (PIN) proteins are plasma-membrane-associated facilitators of auxin transport. They are often targeted to one side of the cell only through subcellular mechanisms that remain largely unknown. Here, we have studied the potential roles of the cytoskeleton and endomembrane system in the localisation of PIN proteins. Immunocytochemistry and image analysis on root cells from Arabidopsis thaliana and maize showed that 10-30% of the intracellular PIN proteins mapped to the Golgi network, but never to prevacuolar compartments. The remaining 70-90% were associated with yet to be identified structures. The maintenance of PIN proteins at the plasma membrane depends on a BFA-sensitive machinery, but not on microtubules and actin filaments.

The polar localisation of PIN proteins at the plasmamembrane was not reflected by any asymmetric distribution of cytoplasmic organelles. In addition, PIN proteins were inserted in a symmetrical manner at both sides of the cell plate during cytokinesis. Together, the data indicate that the localisation of PIN proteins is a postmitotic event, which depends on local characteristics of the plasma membrane and its direct environment. In this context, we present evidence that microtubule arrays might define essential positional information for PIN localisation. This information seems to require the presence of an intact cell wall.
The Rab4 effector Rabip4 plays a role in the endocytotic trafficking of Glut 4 in 3T3-L1 adipocytes
Authors: Mari Muriel , Monzo Pascale , Kaddai Vincent , Keslair Frédérique , Gonzalez Teresa , Le Marchand-Brustel Yannick , Cormont Mireille
Published: March 2006

Insulin regulates glucose uptake in the adipocytes by modulating Glut 4 localization, a traffic pathway involving the endocytic small GTPases Rab4, Rab5, and RabThe expression of the Rab4 effector Rabip4 leads to a 30% increase in glucose uptake and Glut 4 translocation in the presence of insulin, without modifications in the basal condition. This effect was not due to modifications of Glut 4 expression or insulin signaling, suggesting that Rabip4 controls Glut 4 trafficking. We present evidence that Rabip4 defines a subdomain of early endosomes and that Rabip4 is redistributed to the plasma membrane by insulin. Rabip4 is mostly absent from structures positive for early endosome antigen 1, Rab11 or transferrin receptors and from Glut 4 sequestration compartments. However, Rabip4 vesicles can be reached by internalized transferrin and Glut 4. Thus, Rabip4 probably defines an endocytic sorting platform for Glut 4 towards its sequestration pool. The expression of a form of Rabip4 unable to bind Rab4 does not modify basal and insulin-induced glucose transport. However, it induces an increase in the amount of Glut 4 at the plasma membrane and perturbs Glut 4 traffic from endosomes towards its sequestration compartments. These observations suggest that the uncoupling between Rabip4 and Rab4 induces the insertion of Glut 4 molecules that are unable to transport glucose into the plasma membrane.
The return of the peroxisome
Authors: van der Zand Adabella , Braakman Ineke , Geuze Hans J. , Tabak Henk F.
Published: March 2006

Of the classical compartments of eukaryotic cells, peroxisomes were the last to be discovered. They are small, single-membrane-bound vesicles involved in cellular metabolism, most notably the β-oxidation of fatty acids. Characterization of their properties and behavior has progressed rather slowly. However, during the past few years, peroxisomes have entered the limelight as a result of several breakthroughs. These include the observations that they are not autonomously multiplying organelles but are derived from the endoplasmic reticulum, and that partitioning of peroxisomes to progeny cells is an active and well-controlled process. In addition, we are discovering more and more proteins that are not only dedicated to peroxisomes but also serve other organelles.
Photo-Control of Magnetization by Photochromic Compounds
Authors: Einaga Yasuaki
Published: March 2006

The development of new magnetic materials in which magnetic properties are combined with optical properties has been extensively studied. So far, several photo-responsive molecular solids have been reported. However, the strategies that are necessary to achieve photoinduced switching in a solid state are yet to be clarified. Here, I have focused on composite materials as a novel strategy for realizing such photo-functional magnetic systems. These include the incorporation of organic photochromes into magnetic systems, e.g., photo-controllable magnetic vesicles and LB films containing Prussian blue or iron oxide nanoparticles and azobenzene.
Infrared Intensity Study on Molecular Interactions in Quinhydrone
Authors: Kanesaka Isao , Nagami Hideyuki , Kobayashi Kaori , Ohno Keiichi
Published: March 2006

The infrared intensities of the triclinic and monoclinic crystal modifications of quinhydrone (QH) have been measured, along with those of the parent molecules of p-hydroquinone (HQ) and p-benzoquinone (BQ) in solutions and in crystal form. The infrared spectra calculated by the density functional theory indicate that the hydrogen bond between HQ and BQ gives large changes in the infrared intensities of some bands of HQ, but gives rather small changes in the bands of BQ, even in ν(C=O). Charge-transfer interaction in QH is suggested to play an important role for the change in the infrared intensities of ν19a at 1520 cm−1 and τ(C–H) at 530 cm−1 in HQ. In the two crystal modifications of QH, the hydrogen bond is stronger in triclinic QH than in monoclinic QH, whereas the electrostatic interaction is stronger in monoclinic QH than in triclinic QH. The intensity differences of BQ between the CCl4 solution and the crystal are analyzed on the basis of the electrostatic model.
Circular Dichroism of Porphyrin J-Aggregates Induced by Adsorbed d-Tartaric Acid on Mesoporous TiO2 Film
Authors: Fujii Yusuke , Tsukahara Yasunori , Wada Yuji
Published: March 2006

Circular dichroism (CD) signals of J-aggregates of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) fixed on mesoporous TiO2 film were induced by adsorption of d-tartaric acid. The intensity of the induced CD signal at 477 nm derived from TPPS4 J-aggregates adsorbed on TiO2 film increased depending strongly on the concentration of d-tartaric acid dissolved in the surrounding water and the immersion time of TPPS4-adsorbed TiO2 film in acidic water. Especially, in acidic water with high concentrations of d-tartaric acid, the CD intensity increased enormously with the elapse of immersion time, accompanying a decrease of J-aggregates adsorbed on TiO2 film. The amount of d-tartaric acid adsorbed on TiO2 film should determine the CD intensity of J-aggregates. When d-tartaric acid dimethyl ester, which has an effect similar to d-tartaric acid on the induction of CD of TPPS4 J-aggregates in an aqueous solution, was used instead of d-tartaric acid, a slight CD at 477 nm was observed, clearly showing that the chemisorption of chiral molecules on the TiO2 surface through an anchoring group was critical for inducing the CD signal of J-aggregates.
Surface Free Energy and Morphology of Chlorapatite Crystals Grown from Sodium Chloride Flux
Authors: Suzuki Takaomi , Shimuta Mitsunobu , Oishi Shuji
Published: March 2006

Well-formed crystals of barium chlorapatite [Ba5Cl(PO4)3] and strontium chlorapatite [Sr5Cl(PO4)3] were grown from a sodium chloride flux. The contact angle of water on the () face of each chlorapatite crystal was observed using a modified Wilhelmy method, where we measured the change of liquid weight instead of the crystal weight. The contact angle depends on the aspect ratio of the crystal. Both the advancing and receding contact angles were larger for Ba5Cl(PO4)3 and Sr5Cl(PO4)3 crystals with larger aspect ratios. The surface free energy of the () face was calculated using Neumann’s equation. The () face of the crystals of larger aspect ratios has a smaller surface free energy, indicating that such crystals have a more stable () face than the crystals of smaller aspect ratios. This result corresponds to the morphology of the chlorapatite crystals because the crystals have a tendency to elongate into the [0001] direction.
Simultaneous Preconcentration and Determination of Copper, Nickel, Cobalt, Lead, and Iron Content Using a Surfactant-Coated Alumina
Authors: Ghaedi Mehrorang , Asadpour Enayat , Vafaie Azam
Published: March 2006

A sensitive and simple method for the simultaneous determination of nutritionally important minerals including copper, nickel, and iron in real samples is in great demand. Atomic absorption spectrometry (AAS) coupled with a preconcentration method is shown to be an appropriate technique for this objective. The method is based on the formation of mineral complexes by α-benzyl dioxime (BDO) supported on sodium dodecyl sulfate (SDS)-coated alumina. The metal contents in the complexes are eluted using 5 mL of 6 mol L−1 HNO3, and then detected by AAS at respective maximum wavelengths. In this procedure, minerals such as Cu, Ni, Pb, Co, and Fe can be analyzed in one run by carrying out the simultaneous separation and quantification of them. The low detection limit of these elements makes it a superior alternative to UV–vis and in several applications, also an alternative to ICP-MS techniques. The method has been successfully applied for these metal content evaluations in some real samples including waste water, river water, spring water, tap water, vegetable, and baking powder.
Synthesis and Luminescence of New Cu(I) Complexes Containing a Binap Ligand and a Diimine Ligand
Authors: Saito Ken , Tsukuda Toshiaki , Tsubomura Taro
Published: March 2006

A series of novel Cu(I) complexes with an s-binap ligand and a diimine ligand, [Cu(s-binap)(bpy)]PF6, [Cu(s-binap)(phen)]PF6, and [Cu(s-binap)(dmp)]PF6, were synthesized, where bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, and s-binap = (S)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl. All three complexes show intense photoluminescence in the solid state, whereas [Cu(s-binap)(dmp)]PF6 is a comparatively good emitter in CH2Cl2 solutions. These luminescence bands have been assigned to the emission from 3MLCT states. The complexes [Cu(s-binap)(bpy)]PF6 and [Cu(s-binap)(dmp)]PF6 were characterized by X-ray structure analyses. Although the distorted tetrahedral structures around the central metals of the two complexes are similar, the photophysical properties of the dmp complex differ from those of the other complexes in solution. The structures and the photophysical properties of the three complexes have been discussed.
Environmentally Friendly and Efficient Synthesis of Various 1,4-Dihydropyridines in Pure Water
Authors: Wang Guan-Wu , Xia Jing-Jing , Miao Chun-Bao , Wu Xue-Liang
Published: March 2006

An environmentally friendly and efficient synthesis of a series of 1,4-dihydropyridines was developed by the practical one-pot reactions of aldehydes with ammonium acetate and 1,3-dicarbonyl compounds such as alkyl acetoacetate, 5,5-dimethyl-1,3-cyclohexanedione, 1,3-cyclohexanedione, and 2,4-pentanedione in water without any additives under refluxing conditions.
Controlled Deposition of SnS into/onto SnO2 Nano-Particle Film and Application to Photoelectrochemical Cells
Authors: Niinobe Daisuke , Wada Yuji
Published: March 2006

The selective deposition of SnS into/onto SnO2 nano-particle films was performed. The disposition of SnS was controlled by the pH of a source tin solution. The photocurrent of the photoelectrochemical cells using these SnS-deposited SnO2 films depended on where SnS was deposited.
New Water-soluble Organic Ligands for Actinide Cations Complexation
Authors: Sasaki Yuji , Suzuki Hideya , Sugo Yumi , Kimura Takaumi , Choppin Gregory R
Published: March 2006

Novel water-soluble organic ligands, N,N,N′,N′-tetramethyldiglycolamide (TMDGA), N,N,N,N′-tetraethyldiglycolamide (TEDGA), N,N,N′,N′-tetrapropyldiglycolamide (TPDGA), and N,N-dipropyldiglycolamic acid (DPDGAc), were synthesized and examined for complexation with An(III) and An(IV). These reagents are readily soluble in water and form more stable complexes with Pu(IV) and Am(III) than does EDTA of hexadentate ligand. TEDGA and TPDGA can back-extract effectively An into the aqueous phase.
Synthesis of Silicon-bridged Oligothiophenes and Applications to Thin Film Transistors
Authors: Kim Dong-Ha , Ohshita Joji , Kosuge Takao , Kunugi Yoshihito , Kunai Atsutaka
Published: March 2006

Mono- and disilanylene-bridged oligothiophenes were synthesized and their TFT properties were investigated as p-type semiconductors. Among them, the best TFT performance was achieved by using bis(ethylquinquethienyl)dibutylsilane as the active compound whose mobility and on/off ratio were determined to be 2.2 × 10−2 cm2 V−1 s−1 and 105, respectively.
Syntheses and Properties of Oligothiophenes with Cyano and Hexyl Groups
Authors: Wada Hiroshi , Taguchi Tomohiro , Goto Masanao , Kambayashi Takuya , Mori Takehiko , Ishikawa Ken , Takezoe Hideo
Published: March 2006

Syntheses of new oligothiophenes which have cyano and hexyl groups at the ends of quarter- and ter-thiophenes are described. The observations of DSC and polarizing microscopy indicate the presence of liquid-crystalline (LC) phases over a wide temperature range. The energy gaps are discussed on the basis of the absorption and photoluminescence (PL) spectra and cyclic voltammetry. Thin films of oligothiophenes fabricated by vacuum deposition are investigated by AFM and XRD measurements.
Photoluminescence Properties of Ca2Si5N8:Eu2+ Nitride Phosphor Prepared by Carbothermal Reduction and Nitridation Method
Authors: Piao Xianqing , Horikawa Takashi , Hanzawa Hiromasa , Machida Ken-ichi
Published: March 2006

Eu2+ ion-doped nitride phosphor, Ca2Si5N8:Eu2+, was synthesized by the carbothermal reduction and nitridation (CRN) method and the photoluminescence properties were characterized. It showed a broad absorption band between 250 and 550 nm which was efficiently excited by blue LEDs (400–470 nm) and a strong emission band peaking at 600 nm with a FWHM of 80 nm. The obtained phosphor provided saturated color chromaticity (0.589, 0.407) to generate warm-white light in phosphor-converted white LEDs.
Effect of 10 MPa Ammonia Treatment on the Activity of Visible Light Responsive Ta3N5 Photocatalyst
Authors: Lee Yungi , Nukumizu Kota , Watanabe Tomoaki , Takata Tsuyoshi , Hara Michikazu , Yoshimura Masahiro , Domen Kazunari
Published: March 2006

The photocatalytic activity of tantalum nitride (Ta3N5) for H2 evolution under visible-light irradiation (λ > 420 nm) is improved fivefold by 10 MPa ammonia treatment at 823 K. The rate of H2 evolution of the treated samples is highly related to the treatment time and treatment temperature.
Fabrication of an Organic Field-effect Transistor on a Mica Gate Dielectric
Authors: Matsumoto Akira , Onoki Ryo , Ueno Keiji , Ikeda Susumu , Saiki Koichiro
Published: March 2006

We fabricated pentacene-based organic field-effect transistors (OFETs) using single-crystalline natural mica substrates as the gate dielectric. Substrate temperatures during the deposition of pentacene films were varied from room temperature (RT) to 90 °C. Epitaxial growth of the pentacene film on the mica surface was observed even at RT. The FET working characteristics on the mica gate dielectric have been observed for the first time.
Wettability and Superhydrophilic TiO2 Film Formed by Chemical Vapor Deposition
Authors: Kuo Chien-Sheng , Tseng Yao-Hsuan , Li Yuan-Yao
Published: March 2006

A superhydrophilic TiO2 film was prepared by CVD method. In this study, the thickness and roughness of TiO2 film were increased with the increase of oxygen fraction in the inlet flow. A rough surface of TiO2 film exhibited a better original wettability and photoinduced superhydrophilic rate than smooth one. The reasons for the original wettability and photoinduced super-hydrophilicity were explained by Wenzel’s law and the degree of crystallization.
Diastereo- and Enantioselective Tandem Michael Addition and Lactonization between Silyl Enolates and α,β-Unsaturated Ketones Catalyzed by a Chiral Quaternary Ammonium Phenoxide
Authors: Tozawa Takashi , Yamane Yoshinobu , Mukaiyama Teruaki
Published: March 2006

Diastereo- and enantioselective tandem Michael addition and lactonization between various silyl enolates derived from phenyl carboxylates and α,β-unsaturated ketones were successfully carried out by using an efficient organic catalyst, a cinchonidine-derived chiral quaternary ammonium phenoxide. In this asymmetric tandem reaction, the corresponding trans-3,4-dihydropyran-2-ones were obtained in high yields with almost complete diastereoselectivities and good to excellent enantioselectivities.
Two Cubic Phases of 1,2-Bis(4′-n-alkoxybenzoyl)hydrazines (BABH-n)
Authors: Mori Hiroyuki , Kutsumizu Shoichi , Ito Takeya , Fukatami Machiko , Saito Kazuya , Sakajiri Koichi , Moriya Keiichi
Published: March 2006

The structure type of bicontinuous cubic phase formed by 1,2-bis(4′-n-alkoxybenzoyl)hydrazines (BABH) was strongly dependent on the alkoxy chain length, showing the phase sequence of Ia3d–Im3m–Ia3d with lengthening the chain.
Utilization of Microporous and Mesoporous Materials as Supports of Cobalt Catalysts for Regulating Product Distributions in Fischer–Tropsch Synthesis
Authors: Tang Qinghu , Wang Ping , Zhang Qinghong , Wang Ye
Published: March 2006

The utilization of different types of microporous and mesoporous materials as the supports of cobalt catalyst for Fischer–Tropsch synthesis could produce hydrocarbon fuels with different distributions. Among various catalysts investigated, Co/beta and Co/SBA-15 exhibited the highest selectivities to C5–C9 (gasoline fuel fraction) and C10–C20 (diesel fuel fraction) hydrocarbons, respectively.
Book Reviews
Authors: Lev Benjamin
Published: March 2006

The range of books reviewed is wide, covering theory and applications in operations research, statistics, management science, econometrics, mathematics, computers, and information systems (no software is reviewed). In addition, we include books in other fields that emphasize technical applications. Publishers who wish to have their books reviewed should send them to Professor Benjamin Lev. We list the books received; not all books received can be reviewed because space is limited. Those who would like to review books are urged to send me their names, addresses, and specific areas of expertise. We commission all reviews and do not accept unsolicited book reviews. Readers are encouraged to suggest books that might be reviewed or to ask publishers to send me copies of such books.

The authors or editors of the books reviewed in this issue are James Antonio Bucklew, Amiya K. Chakravarty, Jehoshua Eliashberg, Urmila Diwekar, Michael L. Pinedo, Reuven Y. Rubinstein, and Dirk P. Kroese.
An OR/MS Approach to Managing Nanzan Gakuen (Nanzan Educational Complex): From the Strategic to the Daily Operational Level
Authors: Suzuki Atsuo , Sawaki Katsushige , Hasegawa Toshiharu
Published: March 2006

We applied OR/MS methodology to the management of the Nanzan School complex. The administrators recognized OR/MS as a strong effective management tool. They understand that OR/MS is the only tool that can be used to help the school complex change so that it can survive the increasing competition among institutions of higher education. The OR team solved school bus problems, school time problems, and the problem of assigning supervisors for entrance examinations. The team’s initiatives have improved the financial situation of the school complex by saving more than US$2 million between 2003 and 2004. In addition to the direct cost saving, the OR/MS success persuaded many students to choose OR as their major. It also enabled an upgrade of the education quality for the school complex and helped it to retain its prestigious reputation in the region, which helps OR graduates find jobs in Japanese corporations and organizations where they will use OR/MS to induce changes in Japan’s conservative society.
A Scheduling and Capable-to-Promise Application for Swift & Company
Authors: Bixby Ann , Downs Brian , Self Mike
Published: March 2006

Swift & Company uses an integrated system of 45 linear-programming models based on three model formulations to dynamically schedule its beef-fabrication operations at five plants in real time as it receives orders. This scheduling application resulted in documented improvements in key metrics, such as order fulfillment, on-time delivery, and the percentage of a week’s scheduled production for which there are existing orders. The application enabled Swift & Company to execute its business strategy and obtain a 200 percent return on investment in its first year of production.
Changing the Game in Strategic Sourcing at Procter & Gamble: Expressive Competition Enabled by Optimization
Authors: Sandholm Tuomas , Levine David , Concordia Michael , Martyn Paul , Hughes Rick , Jacobs Jim , Begg Dennis
Published: March 2006

Procter & Gamble put into practice CombineNet’s approach to building sourcing networks, called expressive competition. At its heart is a vision that looks past lowest-price reverse auctions and combinatorial package bidding toward a highly expressive commerce relationship with suppliers. It enables suppliers to make electronic offers that express rich forms of capabilities and efficiencies. As the buyer, P&G also uses an expressive language to state constraints and preferences. The detailed expressions of supply and demand are brought together via an advanced optimization engine to decide the optimal allocation of business to the suppliers. By March 2005, over a period of two and a half years, P&G had sourced over $3 billion through expressive commerce and seen $294.8 million (9.6 percent) in recommended savings. In the process, P&G’s suppliers benefited from the win-win approach: expressive competition matched demand to the most efficient means of production (rather than squeezing suppliers’ profit margins) and removed the exposure risks in making offers. Beyond direct monetary savings, the benefits included the redesign of supply networks with quantitative understanding of the trade-offs and the ability to implement in weeks instead of months.
Optimal Component Stocking Policy for Assemble-to-Order Systems with Lead-Time-Dependent Component and Product Pricing
Authors: Hsu Vernon Ning , Lee Chung Yee , So Kut C.
Published: March 2006

Short delivery time and the efficient management of component inventories are two crucial elements that determine the competitiveness of many contract assembly manufacturers, especially in the electronics industry. In this paper, we develop and analyze an optimization model to determine the optimal stocking quantities for components of an assemble-to-order product in an environment where demand is uncertain and the price for the final product and the costs of components depend on their delivery lead times. We provide an efficient solution procedure to solve the problem in which the manufacturer must deliver the full order quantity possibly in multiple shipments. We further extend our model to the situation where the manufacturer has the option of not delivering the full quantity but instead takes the penalty for a delivery shortage. We derive some analytical results that illustrate how different model parameters affect the optimal solution and provide useful insights for managing components in the assemble-to-order environment.
Research Note—Sell First, Fix Later: Impact of Patching on Software Quality
Authors: Arora Ashish , Caulkins Jonathan P. , Telang Rahul
Published: March 2006

We present a model of fixing or patching a software problem after the product has been released in the market. Specifically, we model a software firm’s trade-off in releasing a buggy product early and investments in fixing it later. Just as the marginal cost of producing software can be effectively zero, so can the marginal cost of repairing multiple copies of defective software by issuing patches. We show that due to the fixed cost nature of investments in patching, a software vendor has incentives to release a buggier product early and patch it later in a larger market. Thus, a software monopolist releases a product with fewer bugs but later than what is socially optimal. We contrast this result with physical good markets where market size does not play any role in quality provision. We also show that for comparable costs, a software monopolist releases the product with more bugs but invests more in post-patching support later than the physical good monopolist.
Robustness of Neural Coding inDrosophilaPhotoreceptors in the Absence of Slow Delayed Rectifier K+Channels
Authors: Vähäsöyrinki Mikko , Niven Jeremy E. , Hardie Roger C. , Weckström Matti , Juusola Mikko
Published: March 2006

Determining the contribution of a single type of ion channel to information processing within a neuron requires not only knowledge of the properties of the channel but also understanding of its function within a complex system. We studied the contribution of slow delayed rectifier K+channels to neural coding inDrosophilaphotoreceptors by combining genetic and electrophysiological approaches with biophysical modeling. We show that theShabgene encodes the slow delayed rectifier K+channel and identify a novel voltage-gated K+conductance. Analysis of thein vivorecorded voltage responses together with their computer-simulated counterparts demonstrates thatShabchannels inDrosophilaphotoreceptors attenuate the light-induced depolarization and prevent response saturation in bright light. We also show that reduction of theShabconductance in mutant photoreceptors is accompanied by a proportional drop in their input resistance. This reduction in input resistance partially restores the signaling range, sensitivity, and dynamic coding of light intensities ofShabphotoreceptors to those of the wild-type counterparts. However, loss of theShabchannels may affect both the energy efficiency of coding and the processing of natural stimuli. Our results highlight the role of different types of voltage-gated K+channels in the performance of the photoreceptors and provide insight into functional robustness against the perturbation of specific ion channel composition.
Differential Contributions ofCaenorhabditis elegansHistone Deacetylases to Huntingtin Polyglutamine Toxicity
Authors: Bates Emily A. , Victor Martin , Jones Adriana K. , Shi Yang , Hart Anne C.
Published: March 2006

Expansion of a polyglutamine tract in the huntingtin protein causes neuronal degeneration and death in Huntington's disease patients, but the molecular mechanisms underlying polyglutamine-mediated cell death remain unclear. Previous studies suggest that expanded polyglutamine tracts alter transcription by sequestering glutamine rich transcriptional regulatory proteins, thereby perturbing their function. We tested this hypothesis inCaenorhabditis elegansneurons expressing a human huntingtin fragment with an expanded polyglutamine tract (Htn-Q150). Loss of function alleles and RNA interference (RNAi) were used to examine contributions ofC. eleganscAMP response element-binding protein (CREB), CREB binding protein (CBP), and histone deacetylases (HDACs) to polyglutamine-induced neurodegeneration. Deletion of CREB (crh-1) or loss of one copy of CBP (cbp-1) enhanced polyglutamine toxicity inC. elegansneurons. Loss of function alleles and RNAi were then used to systematically reduce function of eachC. elegansHDAC. Generally, knockdown of individualC. elegansHDACs enhanced Htn-Q150 toxicity, but knockdown ofC. elegans hda-3suppressed toxicity. Neuronal expression ofhda-3restored Htn-Q150 toxicity and suggested thatC. elegans HDAC3(HDA-3) acts within neurons to promote degeneration in response to Htn-Q150. Genetic epistasis experiments suggested that HDA-3 and CRH-1 (C. elegansCREB homolog) directly oppose each other in regulating transcription of genes involved in polyglutamine toxicity.hda-3loss of function failed to suppress increased neurodegeneration inhda-1/+;Htn-Q150animals, indicating that HDA-1 and HDA-3 have different targets with opposing effects on polyglutamine toxicity. Our results suggest that polyglutamine expansions perturb transcription of CREB/CBP targets and that specific targeting of HDACs will be useful in reducing associated neurodegeneration.
Glial Cell Line-Derived Neurotrophic Factor-Dependent Recruitment of Ret into Lipid Rafts Enhances Signaling by Partitioning Ret from Proteasome-Dependent Degradation
Authors: Pierchala Brian A. , Milbrandt Jeffrey , Johnson Eugene M.
Published: March 2006

The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRαs. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.
Three-Dimensional Kinematics at the Level of the Oculomotor Plant
Authors: Klier Eliana M. , Meng Hui , Angelaki Dora E.
Published: March 2006

Motor systems often require that superfluous degrees of freedom be constrained. For the oculomotor system, a redundancy in the degrees of freedom occurs during visually guided eye movements and is solved by implementing Listing’s law and the half-angle rule, kinematic constraints that limit the range of eye positions and angular velocities used by the eyes. These constraints have been attributed either to neurally generated commands or to the physical mechanics of the eye and its surrounding muscles and tissues (i.e., the ocular plant). To directly test whether the ocular plant implements the half-angle rule, critical to the maintenance of Listing’s law, we microstimulated the abducens nerve with the eye at different initial vertical eye positions. We report that the electrically evoked eye velocity exhibits the same eye position dependence as seen in visually guided smooth-pursuit eye movements. These results support an important role for the ocular plant in providing a solution to the degrees-of-freedom problem during eye movements.