bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictors of Prophylactic Bilateral Salpingo-Oophorectomy Compared With Gynecologic Screening Use in BRCA1/2 Mutation Carriers
Authors: Madalinska Joanna B. , van Beurden Marc , Bleiker Eveline M.A. , Valdimarsdottir Heiddis B. , Lubsen-Brandsma Lottie , Massuger Leon F. , Mourits Marian J.E. , Gaarenstroom Katja N. , van Dorst Eleonora B.L. , van der Putten Hans , Boonstra Henk , Aaronson Neil K.
Published: January 2007

Purpose

Women with BRCA1/2 gene mutations who have completed their childbearing are strong candidates for risk-reducing prophylactic bilateral salpingo-oophorectomy (PBSO). The aim of the current study was to identify baseline predictors of PBSO versus gynecologic screening (GS) in this group of high-risk women.

Patients and Methods

Baseline questionnaires were available from 160 BRCA1/2 carriers who participated in a nationwide, longitudinal, observational study of the psychosocial consequences of prophylactic surgery versus periodic screening. Topics addressed by the questionnaire included generic quality of life, cancer-specific distress, risk perception, knowledge of ovarian cancer, and perceived pros and cons of surgery versus screening. PBSO use during the 12-month period after the first gynecologic consultation was determined on the basis of medical record data.

Results

During the 12-month follow-up period, 74% of women had undergone PBSO, and 26% opted for screening. Statistically significant multivariate predictors of PBSO included education, general health perceptions, perceived incurability of ovarian cancer, and perceived benefits of surgery.

Conclusion

Women with lower educational levels, with poorer general health perceptions, who view ovarian cancer as an incurable disease, and who believe more strongly in the benefits of surgery are more likely to undergo PBSO. Clinicians should ensure that high-risk women are well informed about the low predictive value of GS techniques and about the lethal threat posed by ovarian cancer because of its limited curability.
Impact of Chemoradiotherapy After Disease Control With Chemotherapy in Locally Advanced Pancreatic Adenocarcinoma in GERCOR Phase II and III Studies
Authors: Huguet Florence , André Thierry , Hammel Pascal , Artru Pascal , Balosso Jacques , Selle Frédéric , Deniaud-Alexandre Elisabeth , Ruszniewski Philippe , Touboul Emmanuel , Labianca Roberto , de Gramont Aimery , Louvet Christophe
Published: January 2007

Purpose

The management of locally advanced (LA) pancreatic cancer patients remains controversial. To select patients who could benefit from chemoradiotherapy (CRT), the therapeutic strategy used by the Groupe Coopérateur Multidisciplinaire en Oncologie (GERCOR) consisted of initial chemotherapy (CT) for at least 3 months. The decision to administer CRT or continue CT in nonprogressive patients was the investigator's choice.

Patients and Methods

Retrospective analysis of outcome in 181 patients with LA pancreatic cancer (76 women and 105 men; mean age, 61 years; range, 37 to 85 years) enrolled onto prospective phase II and III GERCOR studies was performed to compare the survival of patients who received CRT with that of patients who continued CT alone.

Results

Median progression-free survival (PFS) and overall survival (OS) times for the 181 patients were 6.3 and 11.4 months, respectively. Fifty-three patients (29.3%) had metastatic disease after 3 months of CT and were not eligible for CRT. Among the 128 remaining patients (70.3%) who had no disease progression and who were, therefore, eligible for CRT, 72 (56%) received CRT (group A), whereas 56 (44%) continued with CT (group B). The two groups were balanced for initial characteristics (performance status, sex, age, and type of CT), as well as for induction CT results. In groups A and B, the median PFS times were 10.8 and 7.4 months, respectively (P = .005), and the median OS times were 15.0 and 11.7 months, respectively (P = .0009).

Conclusion

These results suggest that, after control of disease by initial CT, CRT could significantly improve survival in patients with LA pancreatic cancer compared with CT alone. A prospective phase III study is ongoing to evaluate this strategy.
Induction Chemoradiation and Surgical Resection for Superior Sulcus Non–Small-Cell Lung Carcinomas: Long-Term Results of Southwest Oncology Group Trial 9416 (Intergroup Trial 0160)
Authors: Rusch Valerie W. , Giroux Dorothy J. , Kraut Michael J. , Crowley John , Hazuka Mark , Winton Timothy , Johnson David H. , Shulman Lawrence , Shepherd Frances , Deschamps Claude , Livingston Robert B. , Gandara David
Published: January 2007

Purpose

Traditional treatment for superior sulcus non–small-cell lung cancers (SS NSCLC), radiation plus surgery, yields a 50% rate of complete resection and a 30% 5-year survival. On the basis of improved outcomes in other subsets of stage III NSCLC, this trial tested the feasibility of induction chemoradiotherapy for SS NSCLC.

Patients and Methods

Patients with T3-4, N0-1 SS NSCLC received two cycles of cisplatin and etoposide concurrently with radiation (45 Gy). Patients with stable or responding disease underwent thoracotomy. All patients received two more cycles of chemotherapy. Survival was calculated by the Kaplan-Meier method and prognostic factors were assessed by Cox regression analysis.

Results

From April 1995 to November 1999, 110 eligible patients (76 men, 34 women) were entered onto the study (78 T3, 32 T4 tumors). Induction therapy was completed by 104 (95%) patients. Of 95 patients eligible for surgery, 88 (80%) underwent thoracotomy, two (1.8%) died postoperatively, and 83 (76%) had complete resection. Pathologic complete response (CR) or minimal microscopic disease was seen in 61 (56%) resection specimens. Five-year survival was 44% for all patients and 54% after complete resection, with no difference between T3 and T4 tumors. Pathologic CR led to better survival than when any residual disease was present (P = .02). Disease progression occurred mainly in distant sites.

Conclusion

This combined-modality approach is feasible and is associated with high rates of complete resection and pathologic CR in both T3 and T4 tumors. Local control and overall survival seem markedly improved relative to previous studies of radiation plus resection.
Convergent extension, planar-cell-polarity signalling and initiation of mouse neural tube closure
Authors: Ybot-Gonzalez Patricia , Savery Dawn , Gerrelli Dianne , Signore Massimo , Mitchell Claire E. , Faux Clare H. , Greene Nicholas D. E. , Copp Andrew J.
Published: January 2007

Planar-cell-polarity (PCP) signalling is necessary for initiation of neural tube closure in higher vertebrates. In mice with PCP gene mutations, a broad embryonic midline prevents the onset of neurulation through wide spacing of the neural folds. In order to evaluate the role of convergent extension in this defect, we vitally labelled the midline of loop-tail(Lp) embryos mutant for the PCP gene Vangl2. Injection of DiI into the node, and electroporation of a GFP expression vector into the midline neural plate, revealed defective convergent extension in both axial mesoderm and neuroepithelium, before the onset of neurulation. Chimeras containing both wild-type and Lp-mutant cells exhibited mainly wild-type cells in the midline neural plate and notochordal plate, consistent with a cell-autonomous disturbance of convergent extension. Inhibitor studies in whole-embryo culture demonstrated a requirement for signalling via RhoA-Rho kinase, but not jun N-terminal kinase, in convergent extension and the onset of neural tube closure. These findings identify a cell-autonomous defect of convergent extension, requiring PCP signalling via RhoA-Rho kinase, during the development of severe neural tube defects in the mouse.
FoxI1e activates ectoderm formation and controls cell position in theXenopusblastula
Authors: Mir Adnan , Kofron Matt , Zorn Aaron M. , Bajzer Matej , Haque Mansoor , Heasman Janet , Wylie Christopher C.
Published: January 2007

The segregation of the vertebrate embryo into three primary germ layers is one of the earliest developmental decisions. In Xenopus, where the process is best understood, the endoderm is specified by a vegetally localized transcription factor, VegT, which releases nodal signals that specify the adjacent marginal zone of the blastula to become mesoderm. However, little is known about how the ectoderm becomes specified. In this paper, we show that the forkhead protein FoxI1e (also known as Xema) is required at the blastula stage for normal formation of both the central nervous system and epidermis,the two early derivatives of the ectoderm. In addition, FoxI1e is required to maintain the regional identity of the animal cells of the blastula, the cells that are precursors of ectodermal structures. In its absence, they lose contact with the animal cap, mix with cells of other germ layers and differentiate according to their new positions. Because FoxI1e is initially expressed in the animal region of the embryo and is rapidly downregulated in the neural plate, its role in neural and epidermal gene expression must precede the division of the ectoderm into neural and epidermal. The work also shows that FoxI1e plays a role in the embryo in the poorly understood process of differential adhesion, which limits cell mixing as primary germ layers become specified.
Notch2, but not Notch1, is required for proximal fate acquisition in the mammalian nephron
Authors: Cheng Hui-Teng , Kim Mijin , Valerius M. Todd , Surendran Kameswaran , Schuster-Gossler Karin , Gossler Achim , McMahon Andrew P. , Kopan Raphael
Published: January 2007

The Notch pathway regulates cell fate determination in numerous developmental processes. Here we report that Notch2 acts non-redundantly to control the processes of nephron segmentation through an Rbp-J-dependent process. Notch1 and Notch2 are detected in the early renal vesicle. Genetic analysis reveals that only Notch2 is required for the differentiation of proximal nephron structures (podocytes and proximal convoluted tubules)despite the presence of activated Notch1 in the nuclei of putative proximal progenitors. The inability of endogenous Notch1 to compensate for Notch2 deficiency may reflect sub-threshold Notch1 levels in the nucleus. In line with this view, forced expression of a γ-secretase-independent form of Notch1 intracellular domain drives the specification of proximal fates where all endogenous, ligand-dependent Notch signaling is blocked by aγ-secretase inhibitor. These results establish distinct (non-redundant),instructive roles for Notch receptors in nephron segmentation.
Mechanics of dog walking compared with a passive, stiff-limbed, 4-bar linkage model, and their collisional implications
Authors: Usherwood James R. , Williams Sarah B. , Wilson Alan M.
Published: January 2007

Here, we present a simple stiff-limbed passive model of quadrupedal walking, compare mechanics predicted from the model with those observed from forceplate measurements of walking dogs and consider the implications of deviation from model predictions, especially with reference to collision mechanics. The model is based on the geometry of a 4-bar linkage consisting of a stiff hindleg, back, foreleg and the ground between the hind and front feet. It uses empirical morphological and kinematic inputs to determine the fluctuations in potential and kinetic energy, vertical and horizontal forces and energy losses associated with inelastic collisions at each foot placement. Using forceplate measurements to calculate centre of mass motions of walking dogs, we find that (1) dogs may, but are not required to, spend periods of double support (one hind- and one forefoot) agreeing with the passive model;(2) legs are somewhat compliant, and mechanical energy fluctuates during triple support, with mechanical energy being lost directly after hindfoot placement and replaced following forefoot placement. Footfall timings and timing of mechanical energy fluctuations are consistent with strategies to reduce collisional forces, analogous to the suggested role of ankle extension as an efficient powering mechanism in human walking.
Neuroethology of female preference in the synchronously singing bushcricket Mecopoda elongata (Tettigoniidae; Orthoptera): why do followers call at all?
Authors: Fertschai Ismene , Stradner Jürgen , Römer Heiner
Published: January 2007

Imperfect synchrony between male calls occurs in the acoustically interacting bushcricket Mecopoda elongata, and males establishing the temporal leadership attract more females in choice experiments. An asymmetrical representation of leader and follower signals in pairs of direction-selective neurons of the auditory pathway was suggested to represent the neural basis for the preference of females. We investigated the time–intensity trading effect, which occurs when the temporal advantage of the leader signal is compensated, and can be reversed, by an additional sound pressure level of the follower. In behavioural arena trials the intensity trading of the preference of females for leader signals depends on the playback level; a higher sound pressure level (SPL) is needed for compensation at higher playback levels. We studied the simultaneous neuronal representation of leader and follower signals, and the time–intensity trading function in the pair of omega-neurons in the CNS. Consistent with the behavioural data, the representation of leader and follower signals can be reversed with an additional loudness of the follower, and the steepness of the trading function depends on the playback level. We also implemented data on the neuronal representation of synchronized signals in individual receivers into computer-based agents, which performed phonotaxis in a virtual sound field. Results of these simulations closely resemble those obtained from real females with respect to the overall preference under the various time–intensity trading conditions. Furthermore, in combination with the observed trading functions these simulations demonstrate, that under more realistic field conditions the ultimate success of followers in attracting females is much higher than suggested from arena trials. We discuss the evolutionary consequences for male calling strategies in synchronously calling Orthoptera.
Thermogenesis, food intake and serum leptin in cold-exposed lactating Brandt's volesLasiopodomys brandtii
Authors: Zhang Xue-Ying , Wang De-Hua
Published: January 2007

Lactation is the most energetically expensive period for mammals and is associated with increased metabolism and energy intake, but decreased thermogenic capacity. It is well known that small mammals increase both food intake and thermogenesis in the cold. The present study aimed to examine whether Brandt's voles Lasiopodomys brandtii could adjust energy intake and thermogenesis to accommodate simultaneous lactation and cold exposure. The voles were placed into two temperature treatments: warm(23±1°C) and cold (5±1°C). Animals at each temperature treatment were further divided into two groups: non-reproductive (NR) and lactating females. We found that lactating voles at peak lactation in the cold enhanced food intake by 2.6 g day–1 compared with those in the warm, and increased uncoupling protein 1 (UCP1) content in brown adipose tissue (BAT), to the same level as the cold-exposed NR females. Serum leptin levels decreased significantly during lactation and were positively correlated with body mass and fat mass. After correcting for the effects of body mass,residual serum leptin was negatively correlated with residual gross energy intake and residual RMR. In addition, residual serum leptin levels were positively correlated with UCP1 contents in the warm, but not in the cold. Together, these data suggest that lactating voles can increase thermogenic capacity and energy intake to meet the high energetic costs of simultaneous lactation and cold exposure. Further, serum leptin appears to be involved in the energy intake regulation and thermoregulation, but the thermoregulation in the cold may be mainly mediated by other factors.
Biting releases constraints on moray eel feeding kinematics
Authors: Mehta Rita S. , Wainwright Peter C.
Published: January 2007

We present an analysis of prey capture functional morphology in eels by comparing two species of moray eels, Muraena retifera and Echidna nebulosa (Family Muraenidae), to the American eel Anguilla rostrata (Family Anguillidae). The skulls of both moray species exhibited extreme reductions of several prominent components of the suction-feeding mechanism, including the hyoid bar, the sternohyoideus muscle and the pectoral girdle. Associated with these anatomical modifications, morays showed no evidence of using suction during prey capture. From 59 video sequences of morays feeding on pieces of cut squid we saw no hyoid depression and no movement of prey toward the mouth aperture during the strike, a widely used indicator of suction-induced water flow. This was in contrast to A. rostrata, which exhibited a robust hyoid, sternohyoideus muscle and pectoral girdle, and used suction to draw prey into its mouth. Average prey capture time in morays, about 500 ms, was roughly 10 times longer than in A. rostrata, and morays frequently reversed the direction of jaw and head rotation in the midst of the strike. We tested whether the absence of suction feeding reduces temporal constraints on feeding kinematics, permitting greater variance in traits that characterize timing and the extent of motion in the neurocranium, by comparing moray eel species with A. rostrata,two Centrarchids and a cichlid. Kinematic variance was roughly 5 times higher in morays than the suction-feeding species. Prey capture by suction demands a rapid, highly coordinated series of cranial movements and the loss of this mechanism appears to have permitted slower, more variable prey capture kinematics in morays. The alternative prey capture strategy in morays, biting,may be tied to their success as predators in the confined spaces of reef crevices where they hunt for cephalopods, crustaceans and fish.
Effect of maternal myostatin antibody on offspring growth performance and body composition in mice
Authors: Liang Yu-Chuan , Yeh Jan-Ying , Ou Bor-Rung
Published: January 2007

Myostatin (GDF8) is a member of the transforming growth factor beta(TGF-β) superfamily. The finding that animals with a knockout or mutation of the myostatin-encoding gene show increased muscle mass suggests that myostatin negatively regulates muscle growth. The study reported here was designed to investigate the effect of induction of maternal myostatin antibody on the growth performance and body composition of the mouse. Female mice were induced to produce myostatin antibody by immunization with synthetic myostatin peptide prior to mating with male mice. The body masses of offspring were measured weekly and the body compositions of offspring were determined at 8 weeks of age. The results showed that myostatin antibody was detected in both immunized female mice and their 8-week-old offspring. The growth performance of offspring from the myostatin antibody-induced (mstn Ab-induced) group was higher than that from the control group at 8 weeks of age. The body composition of both male and female offspring from the mstn Ab-induced group contained higher crude protein and lower crude fat than those from the control group (P<0.05). The litter number from the maternal mstn Ab-induced group was less than that from control mice, while embryo development was normal in both groups. However, the amount of developing follicle in ovaries of the mstn Ab-induced group was lower than that in the control group. It is concluded that induction of maternal mstn Ab enhances the growth performance of offspring and influences the offspring body composition by increasing the crude protein and reducing crude fat.
Excitable properties of adult skeletal muscle fibres from the honeybeeApis mellifera
Authors: Collet Claude , Belzunces Luc
Published: January 2007

In the hive, a wide range of honeybees tasks such as cell cleaning,nursing, thermogenesis, flight, foraging and inter-individual communication(waggle dance, antennal contact and trophallaxy) depend on proper muscle activity. However, whereas extensive electrophysiological studies have been undertaken over the past ten years to characterize ionic currents underlying the physiological neuronal activity in honeybee, ionic currents underlying skeletal muscle fibre activity in this insect remain, so far, unexplored. Here, we show that, in contrast to many other insect species, action potentials in muscle fibres isolated from adult honeybee metathoracic tibia,are not graded but actual all-or-none responses. Action potentials are blocked by Cd2+ and La3+ but not by tetrodotoxin (TTX) in current-clamp mode of the patch-clamp technique, and as assessed under voltage-clamp, both Ca2+ and K+ currents are involved in shaping action potentials in single muscle fibres. The activation threshold potential for the voltage-dependent Ca2+ current is close to–40 mV, its mean maximal amplitude is –8.5±1.9 A/F and the mean apparent reversal potential is near +40 mV. In honeybees, GABA does not activate any ionic membrane currents in muscle fibres from the tibia, but L-glutamate, an excitatory neurotransmitter at the neuromuscular synapse induces fast activation of an inward current when the membrane potential is voltage clamped close to its resting value. Instead of undergoing desensitization as is the case in many other preparations, a component of this glutamate-activated current has a sustained component, the reversal potential of which is close to 0 mV, as demonstrated with voltage ramps. Future investigations will allow extensive pharmacological characterization of membrane ionic currents and excitation–contraction coupling in skeletal muscle from honeybee, a useful insect that became a model to study many physiological phenomena and which plays a major role in plant pollination and in stability of environmental vegetal biodiversity.
Dimorphic sperm and the unlikely route to fertilisation in the yellow seahorse
Authors: Van Look Katrien J. W. , Dzyuba Borys , Cliffe Alex , Koldewey Heather J. , Holt William V.
Published: January 2007

Uniquely among vertebrates, seahorses and pipefishes (Family Syngnathidae)incubate their eggs within a male brood pouch. This has contributed to a widespread, but poorly founded belief, that the eggs are fertilised using spermatozoa that are deposited directly into the brood pouch via an internal sperm duct. Anatomical dissections showed, however, not only that direct sperm deposition into the pouch is physically impossible, but that spermatozoa must somehow travel a significant distance (>4 mm) outside the body of the male, to reach and fertilise eggs in the pouch. Observations of courtship and mating behaviour also revealed that the pouch closes immediately after mating, and that sperm transfer must occur within a time window of no more than 6 s. In addition to this, the yellow seahorse produces extraordinarily low quantities of dimorphic spermatozoa, but is nevertheless highly fertile and can produce broods that exceed 100 embryos. The entire fertilisation process in seahorses is therefore uniquely efficient among vertebrates, yet paradoxically involves several steps that would seem to complicate, and even appear to prevent, the interaction of the gametes. Although we are still unable to describe the exact fertilisation mechanism, we speculate that spermatozoa are ejaculated into a mixture of ovarian fluid and eggs, while the male and female are in close contact. Thereafter, this mixture must enter the pouch, whereupon the spermatozoa encounter seawater. These observations also support the view, indirectly inferred in previous publications, that sperm competition in seahorses is not only non-existent but impossible.
Active space of a movement-based signal: response to the Jacky dragon(Amphibolurus muricatus) display is sensitive to distance, but independent of orientation
Authors: Peters Richard A. , Evans Christopher S.
Published: January 2007

The efficacy of any animal signal is constrained by the range over which it remains above the sensory threshold of potential receivers. The spatial area in which reliable detection occurs defines active space; this is influenced by signal structure, the signalling environment and the sensory characteristics of receivers. Identification of the factors influencing active space has provided valuable insights into signal design, particularly in bioacoustics,in which signal distortion and degradation can be easily quantified. In the present study, we consider whether active space can similarly help to explain the design of a movement-based visual signal. The Jacky dragon(Amphibolurus muricatus) threat display is composed of five distinct motor patterns delivered in an obligatory sequence: tail-flicks, backward and forward foreleg waves, a push-up and a `body-rock'. In contrast to other communication systems, the introductory element is characterized by reduced intensity (average speed) but greater duration than subsequent motor patterns. Furthermore, the tail-flick sweeps a three-dimensional (3D) space around the lizard, whereas the motor patterns that follow are largely restricted to a single plane. Structural properties thus suggest that the active space of the tail-flick might be greater than that of the other motor patterns in the display, which would provide a parsimonious explanation for its use as an alerting component. We tested this prediction in a playback experiment incorporating 3D animations of lizard displays, comparing response probabilities to the factorial combination of three motor patterns, three viewing angles and three distances. Results suggest that the tail-flick does not have a greater active space than other display motor patterns, but that each degrades predictably with distance, thereby providing potential ranging cues. In addition, display components are remarkably robust to variation in receiver orientation, so that efficacy should be maximized in most potential signalling situations. These findings are consistent with the hypothesis that duration is the principal determinant of signal efficacy in this system.
Sonochemical Fabrication and Photoluminescence Properties of Ordered Mesoporous Carbon–Tin Oxide Nanocomposites
Authors: Cao Yulin , Cao Jieming , Liu Jinsong , Zheng Mingbo , Shen Kai
Published: January 2007

A new ordered mesoporous carbon–tin oxide (OMC–SnO2) nanocomposite has been prepared for the first time by a simple and efficient sonochemical route at room temperature. The resulting SnO2 nanoparticles are about 3 nm in size and highly dispersed on ordered mesoporous carbon. The photoluminescence properties of the OMC–SnO2 composites are also firstly described. This method is proposed as a simple and general method to prepare new functionalized ordered mesoporous carbon materials with other nanoparticles for various applications.
Solid-state 2H NMR Study of Nanocrystal Formation of D2O and Their Dynamic Aspects in ACF Hydrophobic Nanospaces
Authors: Omichi Hiroaki , Ueda Takahiro , Miyakubo Keisuke , Eguchi Taro
Published: January 2007

Molecular motion of heavy water confined in activated carbon fiber (ACF) was investigated using solid-state 2H NMR. The 2H NMR spectrum indicated that π-flip motion as well as tetrahedral jump of D2O was active below 190 K, suggesting the formation of nanocrystal of D2O in the ACF nanoslits.
Polyoxometalate-based Colloidal Crystal Thin Film
Authors: Chai Fang , Wang Xiaohong , Tan Rongxin , Cao Fenghua , Zhai Fengying , Xu Linlin , Shao Changlu , Liu Yichun
Published: January 2007

An inverse opal structure three-dimensional array film of polyoxometalates (POMs) was constructed by using polystyrene (PS) colloidal crystals as templates. The thin film has exact inverse opal structure and the POMs remained Keggin stucture.
Novel Electron-transport Material Containing Boron Atom with a High Triplet Excited Energy Level
Authors: Tanaka Daisaku , Takeda Takashi , Chiba Takayuki , Watanabe Soichi , Kido Junji
Published: January 2007

Tris-[3-(3-pyridyl)mesityl]borane (3TPYMB) with high triplet excited energy level was synthesized and investigated as an electron-transport material for organic light-emitting devices (OLEDs). Larger current density and higher luminance were observed for the OLED using 3TPYMB, compared with the OLED with a conventional electron-transport material, tris(8-quinolinolato)aluminum (Alq3).
Novel Preparation Method of Cross-linked Sulfonated Polyimide Membranes for Fuel Cell Application
Authors: Kido Masayoshi , Hu Zhaoxia , Ogo Takahiro , Suto Yoshiki , Okamoto Ken-ichi , Fang Jianhua
Published: January 2007

A facile cross-linking method has been successfully developed for sulfonated polyimide (SPI) membranes. The SPIs with electron-rich phenyl rings in the non-sulfonated diamine moiety were readily cross-linked by immersing the membranes into a solution of phosphorous pentoxide and methanesulfonic acid at 30–80 °C. The resulting SPI membranes cross-linked via sulfonyl groups showed greatly improved water stability compared with the uncross-linked ones, while high proton conductivity was maintained. They have potential for fuel cells at high temperatures above 80 °C.
The Effect of Axial Ligand on the Reactivity of Oxomanganese(V) Corrole
Authors: Liu Hai-Yang , Zhou Hua , Liu Lan-Ying , Ying Xiao , Jiang Huan-Feng , Chang Chi-Kwong
Published: January 2007

The effect of axial ligand on the reactivity of oxomanganese(V) 5,10,15-tris(pentafluorophenyl)corrole (tpfc)MnVO had been investigated by kinetic method. It was found the reactivity of (tpfc)MnVO towards styrene could be greatly enhanced by axial coordination interaction. Catalytic experiments indicated that the turnover frequency (TOF) of (tpfc)MnIII-catalyzed epoxidation of styrene with PhIO was increased about 7 times in the presence of imidazole (catalyst/ligand, 1:10). Theoretical calculations showed that axial coordination will lower the binding energy of Mn=O bond in (tpfc)MnVO.
Azaspirovesamicols—Regioselective Synthesis and Crystal Structure Analysis of a Novel Class of Vesamicol Analogues as Potential Ligands for the Vesicular Acetylcholine Transporter
Authors: Wenzel Barbara , Bats Jan W , Scheunemann Matthias , Steinbach Jörg
Published: January 2007

This report describes the high regioselectivity of nucleophilic epoxide ring-opening reactions which resulted in two of four possible regioisomers of N-benzoyl- (5a and 5b) and N-fluorobenzoylazaspirovesamicol derivatives (6a and 6b), respectively. Based on structural information obtained from X-ray crystal structure analyses of 5a and 5b the mode of epoxide ring-opening is discussed.
A Hydrogen-bonded Supramolecular Hexagonal Columnar Liquid Crystal Composed of a Tricarboxylic Triphenylene and Monopyridyl Dendrons
Authors: Ishihara Shinsuke , Furuki Yuusuke , Takeoka Shinji
Published: January 2007

Tricarboxylic triphenylene (TPC5) and monopyridyl dendron (DenC12) were mixed in 1:2, 1:3, and 1:4 molar ratios, and investigation by IR, DSC, and XRD studies proved that TPC5 and DenC12 self-assembled to form a hexagonal columnar liquid crystal with 1:3 molar stoichiometry via complementary hydrogen-bonds.
Multiphoton Ionization Detection of Aromatic Hydrocarbons at 157.6 nm
Authors: Kanno Nozomu , Yabushita Akihiro , Kawasaki Masahiro , Tonokura Kenichi
Published: January 2007

Multiphoton ionization at 157.6 nm using F2 laser has been used for the detection of benzene, toluene, and chlorobenzene. In all the photoionization spectra, the fragment ion signal intensities were stronger than those of the molecular ions. The detection limits of the compounds are discussed in terms of the multiphoton ionization schemes of the compounds.
Main Chain-type Polyrotaxane with Controlled Ratio of Rotaxanated Units
Authors: Takata Toshikazu , Kohsaka Yasuhiro , Konishi Gen-ichi
Published: January 2007

A novel main-chain type polyrotaxane having a rotaxanated crown ether backbone was synthesized by the rotaxanation of poly(crown ether). The rotaxanated ratio of the main chain increased up to ca. 100% with increase of amount of sec-ammonium axle used.
Spin Orientation of Iron Films Produced by Laser Deposition
Authors: Yamada Yasuhiro , Namiki Kentarou
Published: January 2007

Iron films deposited on Al substrates were investigated using Mössbauer spectroscopy and scanning electron microscopy. It was found that the nuclear spin orientation of iron films produced by deposition of Fe atoms vaporized by resistive heating was perpendicular to the substrate surface, while that of films produced by laser deposition of Fe was parallel to the substrate surface. The droplets produced by laser deposition have a disk-like shape and perturb the spin orientation of the film.
Research on Innovation: A Review and Agenda forMarketing Science
Authors: Hauser John , Tellis Gerard J. , Griffin Abbie
Published: January 2007

Innovation is one of the most important issues in business research today. It has been studied in many independent research traditions. Our understanding and study of innovation can benefit from an integrative review of these research traditions. In so doing, we identify 16 topics relevant to marketing science, which we classify under five research fields:

Consumer response to innovation, including attempts to measure consumer innovativeness, models of new product growth, and recent ideas on network externalities; Organizations and innovation, which are increasingly important as product development becomes more complex and tools more effective but demanding;. Market entry strategies, which includes recent research on technology revolution, extensive marketing science research on strategies for entry, and issues of portfolio management; Prescriptive techniques for product development processes, which have been transformed through global pressures, increasingly accurate customer input, Web-based communication for dispersed and global product design, and new tools for dealing with complexity over time and across product lines; Defending against market entry and capturing the rewards of innovating, which includes extensive marketing science research on strategies of defense, managing through metrics, and rewards to entrants.

For each topic, we summarize key concepts and highlight research challenges. For prescriptive research topics, we also review current thinking and applications. For descriptive topics, we review key findings.
Brands and Branding: Research Findings and Future Priorities
Authors: Keller Kevin Lane , Lehmann Donald R.
Published: January 2007

Branding has emerged as a top management priority in the last decade due to the growing realization that brands are one of the most valuable intangible assets that firms have. Driven in part by this intense industry interest, academic researchers have explored a number of different brand-related topics in recent years, generating scores of papers, articles, research reports, and books. This paper identifies some of the influential work in the branding area, highlighting what has been learned from an academic perspective on important topics such as brand positioning, brand integration, brand-equity measurement, brand growth, and brand management. The paper also outlines some gaps that exist in the research of branding and brand equity and formulates a series of related research questions. Choice modeling implications of the branding concept and the challenges of incorporating main and interaction effects of branding as well as the impact of competition are discussed.
Invited Commentary—Research and the Motion Picture Industry
Authors: Weinberg Charles B.
Published: January 2007

The motion picture industry features challenging management problems and appealing research opportunities. Based on research findings, three challenges for managers are the need to (1) view movies as just one part of the product line, (2) consider the evolution of the first-run exhibition channel, and (3) take a global perspective in decision making. For researchers, the motion picture industry is a data-intensive natural laboratory that allows for empirical testing of important research questions. The study of competitive dynamics and contractual issues are highlighted as topics of particular relevance.
The Motion Picture Industry: Critical Issues in Practice, Current Research, and New Research Directions
Authors: Eliashberg Jehoshua , Elberse Anita , Leenders Mark A.A.M.
Published: January 2007

The motion picture industry has provided a fruitful research domain for scholars in marketing and other disciplines. The industry has high economic importance and is appealing to researchers because it offers both rich data that cover the entire product lifecycle for many new products and because it provides many unsolved “puzzles.” Although the amount of scholarly research in this area is rapidly growing, its impact on practice has not been as significant as in other industries (e.g., consumer packaged goods). In this article, we discuss critical practical issues for the motion picture industry, review existing knowledge on those issues, and outline promising research directions. Our review is organized around the three key stages in the value chain for theatrical motion pictures: production, distribution, and exhibition. Focusing on what we believe are critical managerial issues, we propose various conjectures—framed either as research challenges or specific research hypotheses—related to each stage in the value chain and often involved in understanding consumer movie-going behavior.
Invited Commentary—Empirical Analysis of Theory-Based Models in Marketing
Authors: Srinivasan Kannan
Published: January 2007

There has been rapidly growing interest in structural models, and the review paper by Chintagunta et al. (2006) is a timely contribution. The paper identifies the key issues and provides an excellent assessment. A contemporaneous paper by Erdem et al. (2005) also offers a critical examination on some of the issues. My comments are in three areas. First, I selectively revisit some of the key issues in the paper and, in doing so, I hope I shed additional insight on these issues. Second, I discuss some of the recent papers that build on established psychological consumer behaviors. Third, I offer a brief list of potentially significant substantive problems for which structural models will be insightful.
Customer Metrics and Their Impact on Financial Performance
Authors: Gupta Sunil , Zeithaml Valarie
Published: January 2007

The need to understand the relationships among customer metrics and profitability has never been more critical. These relationships are pivotal to tracking and justifying firms’ marketing expenditures, which have come under increasing pressure. The objective of this paper is to integrate existing knowledge and research about the impact of customer metrics on firms’ financial performance. We investigate both unobservable or perceptual customer metrics (e.g., customer satisfaction) and observable or behavioral metrics (e.g., customer retention and lifetime value). We begin with an overview of unobservable and observable metrics, showing how they have been measured and modeled in research. We next offer nine empirical generalizations about the linkages between perceptual and behavioral metrics and their impact on financial performance. We conclude the paper with future research challenges.
Invited Commentary—Marketing Structural Models: “Keep It Real”
Authors: Mazzeo Michael J.
Published: January 2007

In their article, “Structural Modeling in Marketing: Review and Assessment,” Chintagunta, Erdem, Rossi, and Wedel (2006) provide a comprehensive survey of the contributions to the empirical marketing literature made by researchers using structural econometric modeling. More importantly, their review poses the question of whether structural methods should become more prominent in marketing research. Addressing that question requires a careful consideration of the potential gains of employing structure in this context, as well as the compromises necessary for implementation. Instead of specifically referencing many of the interesting papers cited by the authors, I will focus my comment on evaluating the value of structural approaches in marketing in more general terms.
Commentary—Antibusiness Movies and Folk Marketing
Authors: Shugan Steven M.
Published: January 2007

We observe a disproportional number of movies that vividly portray business and businesspeople with an unfavorable bias, often depicting ordinary business activity as zero-sum and sometimes depicting it as callous, immoral, and criminal. These movies also often aggrevate existing economic misconceptions that might include what we could call folk marketing. Folk marketing includes false ideas, such as marketing being a zero-sum game (rather than adding value), marketing research being intrusive clandestine surveillance (rather than advocating the buy viewpoint), and secrecy about market data being evidence of nefarious activities (rather than simply hiding strategies from competitors). Marketing scholars need to combat vigorously these false ideas. Moreover, when advertisements sponsor movies, it might be necessary to consider the conjoined movie content and the consistency of that content with the desired brand image.
Editorial: Fifty Years of Marketing Science
Authors: Shugan Steven M.
Published: January 2007

We have observed conspicuous changes in the 25 years after Frank M. Bass, John D. C. Little, and Donald G. Morrison begot Marketing Science. Marketing Science benefited from five subsequent editors and fifty different area editors. New submissions grew from 40 to over 320. Published articles grew from 16 to over 45 per year. We discuss six possible developments for the next 25 years. (1) The Internet’s extraordinary search capabilities will diminish the distinctiveness of each journal. (2) The Internet will allow any researcher to publish research without journals. (3) Faster dissemination is inevitable. (4) Many economical electronic journals will enter the market. (5) The business model of print journals must change. (6) We will publish new forms of content (e.g., videos, blogs, running reviews, and subsequent comments by the authors).
An Analytical Model for Traffic Delays and the Dynamic User Equilibrium Problem
Authors: Perakis Georgia , Roels Guillaume
Published: January 2007

In urban transportation planning, it has become critical (1) to determine the travel time of a traveler and how it is affected by congestion, and (2) to understand how traffic distributes in a transportation network. In the first part of this paper, we derive an analytical function of travel time, based on the theory of kinematic waves. This travel-time function integrates the traffic dynamics as well as the effects of shocks. Numerical examples demonstrate the quality of the analytical function, in comparison with simulated travel times. In the second part of this paper, we incorporate the travel-time model within a dynamic user equilibrium (DUE) setting. We prove that the travel-time function is continuous and strictly monotone if the flow varies smoothly. We illustrate how the model applies to solve a large network assignment problem through a numerical example.
Expected Value of Distribution Information for the Newsvendor Problem
Authors: Yue Jinfeng , Chen Bintong , Wang Min-Chiang
Published: January 2007

This paper extends previous work on the distribution-free newsvendor problem, where only partial information about the demand distribution is available. More specifically, the analysis assumes that the demand distribution f belongs to a class of probability distribution functions (pdf) ℱ with mean μ and standard deviation σ. While previous work has examined the expected value of distribution information (EVDI) for a particular order quantity and a particular pdf f, this paper aims at computing the maximum EVDI over all f ∈ ℱ for any order quantity. In addition, an optimization procedure is provided to calculate the order quantity that minimizes the maximum EVDI.
Piled-Slab Searches
Authors: Washburn Alan
Published: January 2007

This paper deals with the conflict between simplicity and optimality in searching for a stationary target whose location is distributed in two dimensions, thus continuing an analysis that was begun in World War II. The search is assumed to be of the “piled-slab” type, where each slab consists of a uniform search of some simple region. The measure of simplicity is the number of regions (smaller is simpler). If each of a fixed number of elliptical regions is searched randomly, we find the optimal region size and the optimal division of effort between regions. Rectangular regions are also considered, as are problems where the regional searches are according to the inverse-cube law, instead of random search. There is a strong tendency for optimal inverse-cube law searches to consist of a single slab. We also consider problems where the amount of effort for each region is optimized myopically, with no consideration for the search of future regions.
Online Low-Price Guarantees—A Real Options Analysis
Authors: Marcus Benjamin , Anderson Chris K.
Published: January 2007

A common practice among large retailers is the low-price guarantee, rebating consumers if they find an identical product cheaper elsewhere. This provides consumers with some level of comfort in their purchase decision. A similar low-price guarantee is provided by numerous service industries that allow reservation of capacity, yet do not penalize the consumer for failure to keep that reservation—examples include hotels and car rental. Given that a consumer is not required to keep the reservation, they may make another reservation, either at a competing firm or the same firm, if future prices decline. The increasing availability of pricing information on the Internet affords consumers the opportunity to be more strategic in their purchasing behavior. As consumers, we are able to quickly and easily check prices from numerous service or goods providers. The ease of price information potentially makes these guarantees very costly to the service or good provider. We analyze the implied costs associated with these guarantees by making analogies to financial options. Motivation for this research comes from a large car rental firm, Dollar Thrifty Automotive Group Inc., that considered offering a low-price guarantee to all consumers that book a reservation though their website.
On the Effects of Dimension Reduction Techniques on Some High-Dimensional Problems in Finance
Authors: Wang Xiaoqun
Published: January 2007

Many problems in finance can be formulated as high-dimensional integrals, which are often attacked by quasi-Monte Carlo (QMC) algorithms. To enhance QMC algorithms, dimension reduction techniques, such as the Brownian bridge (BB) and principal component analysis (PCA), are used to reduce the effective dimension. This paper explores in depth the effects of these techniques on the dimension structure of some typical high-dimensional problems from finance: the pricing of path-dependent options and bond valuation according to term structure models. By deriving explicit expressions for the underlying integrands and the associated weights that control the relative importance of different variables, and by investigating the variance ratios, the effective dimensions, the mean dimension, and their limiting behavior as the nominal dimension tends to infinity, we show theoretically and empirically how and to what extent the BB and PCA algorithms change the dimension structure (including the degree of additivity) of the underlying functions. They change the functions to be strongly weighted and substantially reduce the effective dimensions and the mean dimension; and they enhance the degree of additivity, which is particularly important for QMC. Moreover, the resulting functions are of low effective dimension, not only in the superposition sense, but also in the truncation sense. The variance ratios, the effective dimensions, and the mean dimension associated with these techniques are very insensitive to the nominal dimension (they are essentially constant), which highlights the possibility of removing the curse of dimensionality when dimension reduction techniques are used in combination with QMC. A counterexample is also shown for which the BB and PCA may increase the effective dimension. The investigation provides further insight into the effects of dimension reduction techniques.