bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Introduction of Positron Emission Tomography on Adherence to Mediastinal Staging Protocols and Performance of Mediastinoscopy
Authors: Goosens Martijn , Smulders Sietske A. , Smeenk Frank W. , Daniëls-Gooszen Alette W. , Donkers-van Rossum Astrid B. , Edelbroek Michela A. , Huysmans Dyde A. , Michels Arent-Jan , van Straten Bart A.H.M. , Postmus Pieter E. 
Published: September 2007

Purpose In this study, we investigated the impact of implementation of [18F] fluorodeoxyglucose positron emission tomography (FDG-PET) in daily practice on adherence to mediastinal staging protocols and performance of mediastinoscopy in non–small-cell lung cancer (NSCLC) patients who are possible candidates for surgical resection. Institutional review board approval was obtained. Patients and Methods From a nonuniversity teaching hospital and three surrounding community hospitals in Eindhoven, the Netherlands, we studied data from 143 patients with NSCLC who underwent mediastinoscopy and/or thoracotomy in three consecutive periods (1, 0 to 9 months; 2, 10 to 18 months; and 3, 19 to 31 months) after introduction of PET. Mediastinoscopy was indicated in case of enlarged and/or PET-positive nodes. Adherence to these surgical mediastinal staging guidelines and the performance of PET and mediastinoscopy were investigated and compared between the three periods and with our previous study before introduction of PET. Results and Conclusion Guidelines for indicating mediastinoscopy were adequately followed in significantly more instances after introduction of PET (80%), compared with the period before PET (66%). Optimal yield (lymph node stations 4, right and left, and 7) of mediastinoscopy (in 27% of patients) was not significantly different from the period before PET (39% of patients). Compared with the historical data, the percentage of positive mediastinoscopies increased from 15.5 to 17.6 (not significant). We found no significant differences between the three consecutive periods with regard to adequacy of indicating and performance of mediastinoscopy. After introduction of PET, adherence to staging guidelines with respect to mediastinoscopy improved. Although fewer mediastinoscopies had an optimal yield, more proved to be positive for metastases. Nevertheless, when a mediastinoscopy is indicated, surgeons must be encouraged to reach an optimal yield because PET positive nodes might be false negative. This occurred in 5% to 6% of all patients.
27-Hydroxycholesterol Is an Endogenous Selective Estrogen Receptor Modulator
Authors: DuSell Carolyn D. , Umetani Michihisa , Shaul Philip W. , Mangelsdorf David J. , McDonnell Donald P. 
Published: September 2007

AbstractSelective estrogen receptor (ER) modulators (SERMs) are ER ligands whose relative agonist/antagonist activities vary in a cell- and promoter-dependent manner. The molecular basis underlying this selectivity can be attributed to the ability of these ligands to induce distinct alterations in ER structure leading to differential recruitment of coactivators and corepressors. Whether SERM activity is restricted to synthetic ligands or whether molecules exist in vivo that function in an analogous manner remains unresolved. However, the recent observation that oxysterols bind ER and antagonize the actions of 17β-estradiol (E2) on the vascular wall suggests that this class of ligands may possess SERM activity. We demonstrate here that 27-hydroxycholesterol (27HC), the most prevalent oxysterol in circulation, functions as a SERM, the efficacy of which varies when assessed on different endpoints. Importantly, 27HC positively regulates both gene transcription and cell proliferation in cellular models of breast cancer. Using combinatorial peptide phage display, we have determined that 27HC induces a unique conformational change in both ERα and ERβ, distinguishing it from E2 and other SERMs. Thus, as with other ER ligands, it appears that the unique pharmacological activity of 27HC relates to its ability to impact ER structure and modulate cofactor recruitment. Cumulatively, these data indicate that 27HC is an endogenous SERM with partial agonist activity in breast cancer cells and suggest that it may influence the pathology of breast cancer. Moreover, given the product-precursor relationship between 27HC and cholesterol, our findings have implications with respect to breast cancer risk in obese/hypercholesteremic individuals.
American Health Policy: Cracks in the Foundation
Authors: Nyman John A. 
Published: September 2007

Much American health policy over the past thirty-five years has focused on reducing the additional health care that is consumed when a person becomes insured, that is, reducing moral hazard. According to conventional theory, all of moral hazard represents a welfare loss to society because its cost exceeds its value. Empirical support for this theory has been provided by the RAND Health Insurance Experiment, which found that moral hazard—even moral hazard in the form of effective and appropriate hospital procedures—could be reduced substantially using cost-sharing policies with little or no measurable effect on health.This article critically analyzes these two cornerstones of American health policy. It holds that a large portion of moral hazard actually represents health care that ill consumers would not otherwise have access to without the income that is transferred to them through insurance. This portion of moral hazard is efficient and generates a welfare gain. Further, it holds that the RAND experiment's finding (that health care could be reduced substantially with little or no effect on health) may actually be caused by the large number of participants who voluntarily dropped out of the cost-sharing arms of the experiment. Indeed, almost all of the reduction in hospital use in the cost-sharing plans could be attributed to this voluntary attrition. If so, the RAND finding that cost sharing could reduce health care utilization, especially utilization in the form of effective and appropriate hospital procedures, with no appreciable effect on health is spurious.The article concludes by observing that the preoccupation with moral hazard is misplaced and has worked to obscure policies that would better reduce health care expenditures. It has also led us away from policies that would extend insurance coverage to the uninsured.
The Impact of the Adoption of Gag Laws on Trust in the Patient-Physician Relationship
Authors: Patel Mitesh S. , Chernew Michael E. 
Published: September 2007

Physician organizations, policy makers, and patient advocates have expressed concern that health plans have contractually limited the freedom of physicians to communicate with their patients. In response, many states have adopted gag laws that limit the ability of managed care contracts to restrict patient-physician communication. We examine the impact of these laws on patient trust in the physician.We analyzed patients' ratings of trust in their physicians in states before and after adoption of gag laws. Individuals in states that had such laws throughout the study period were used as the comparison group. The analysis is based on a nationally representative sample of adults obtained from the 1996-1997 and 1998-1999 Community Tracking Study Household Surveys.After adjustment for patient characteristics, it was estimated that the adoption of gag laws had no statistically significant impact on trust in the physician for the average patient. However, the adoption of gag laws is estimated to have increased trust in the physician by a modest amount (25 percent of a standard deviation) for health maintenance organization (HMO) enrollees who did not have a usual source of care.Gag laws may assure HMO enrollees without a usual source of care that their physicians are free to speak candidly about treatment options. This does not necessarily imply that physicians are prohibited from speaking freely in the absence of such laws, but gag laws indicate concerns (justified or not) that patients have about unrestricted communication with their health care providers.
Uniform strain in broad muscles: active and passive effects of the twisted tendon of the spotted ratfish Hydrolagus colliei
Authors: Dean Mason N. , Azizi Emanuel , Summers Adam P. 
Published: September 2007

SUMMARY
A muscle's force output depends on the range of lengths over which its fibers operate. Regional variation in fiber shortening during muscle contraction may translate into suboptimal force production if a subset of muscle fibers operates outside the plateau of the length–tension curve. Muscles with broad insertions and substantial shortening are particularly prone to heterogeneous strain patterns since fibers from different regions of the muscle vary in their moment arms, with fibers further from the joint exhibiting greater strains. In the present study, we describe a musculotendon morphology that serves to counteract the variation in moment arm and fiber strains that are inherent in broad muscles. The tendon of the anterior jaw adductor of the spotted ratfish Hydrolagus colliei is twisted such that the distal face of the muscle inserts more proximally than the proximal face. Using quantitative geometric models based on this natural morphology, we show that this inversion of insertion points serves to equalize strains across the muscle such that at any gape angle all fibers in the muscle are operating at similar positions on their length–tension curves. Manipulations of this geometric model show that the natural morphology is `ideal' compared to other hypothetical morphologies for limiting fiber strain heterogeneity. The uniform strain patterns predicted for this morphology could increase active force production during jaw closing and also decrease passive resistance to jaw opening. This divergence from `typical' tendon morphology in the jaw adductors of H. colliei may be particularly important given the demands for high force production in durophagy.
Organometallic Electron-Reservoir Complexes. Concepts and Applications
Authors: Astruc Didier 
Published: September 2007

Abstract
The 19-electron complexes [FeI(η5-C5R5)(η6-arene)] (R=H, arene = C6Me6, 1,3,5-tBu3C6H3; R=Me, arene = C6Me6, C6Et5H) are thermally stable and serve as strong single-electron reductant in a variety of stoichiometric and catalytic electron-transfer processes that are detailed in this review (prototype: [FeI(η5-C5H5)(η6-C6Me6)]). They are electron-reservoirs because their redox potential is very negative and they form a redox system for which both redox forms are stable. In this sense, they are Green redox reagents, since the oxidized form is recovered after use and is even frequently catalytically used. Symmetrically, the 17-electron complex [FeIII(η5-C5R5)(η6-C6Me6)][SbCl6]2, the strongest organometallic single-electron oxidant with a redox potential 1 V more positive than that of its isoelectronic ferrocenium analog, is a reservoir of electron hole.
Demonstration of the Importance of Metal Ion Speciation in Bioactive Systems
Authors: Kiss Tamás , Odani Akira 
Published: September 2007

Abstract
This paper gives insight into chemical speciation. After a brief introduction, the methods available to study solution state of metal ions and the importance of speciation in biology are discussed through different examples. Speciation of toxic AlIII, beneficial CuII and CaII and potentially medicinal PdII and VOIV in various biofluids and tissues is discussed in order to describe the solution state of these metal ions in an organism. The relevance of ternary complex formation with endogenous biomolecules is emphasised. The importance of the biospeciation of AlIII ion in its transport and involvement in neurological disorders, of the actual chemical form of the insulin-mimetic VOIV complexes in its biological occurrence and CaII in mineralization/demineralization processes is discussed. The role of time, i.e., the kinetic aspects of biospeciation, is discussed in the case of the transport of AlIII and CuII and some PdII complexes (models of the anticancer PtII complexes) in blood serum.
Phase Transitions and Molecular Motions in Guanidinium-d6 Trihalogenomercurates(II) [C(ND2)3]HgBr3 and [C(ND2)3]HgI3 as Investigated by Means of 81Br and 127I NQR and 2H NMR
Authors: Yamada Koji , Terao Hiromitsu , Sumimura Kazuko , Hashimoto Masao , Ohki Hiroshi , Okuda Tsutomu 
Published: September 2007

Abstract
The temperature dependence of 2H NMR spectra and 81Br and 127I NQR frequencies was investigated for the deuterated compounds of [C(NH2)3]HgBr3 and [C(NH2)3]HgI3 between 77 and ca. 400 K. Due to deuteration, the phase-transition temperatures of the iodine compound were increased by 2 and 6 K for the second-order (251 K) and the first-order (210 K) phase transitions, respectively. Distinctive 127I NQR frequency-shifts of more than 200 kHz were observed in the intermediate phase of the iodine compound on deuteration. The temperature dependences of the 2H NMR spectra for [C(ND2)3]HgBr3 and [C(ND2)3]HgI3 could be explained by invoking C3 reorientation of the guanidinium cation. The activation energies for the reorientation evaluated from 2H NMR were consistent with the former 1H NMR T1 results with the exception of the low-temperature phase of the iodine compound. The quite low activation energy from 2H NMR spectrum for this phase may indicate that the quenching of the orientation disordering of the cations is responsible for the fade-out phenomenon in the 127I NQR resonance lines below ca. 100 K.
Quantum Chemical Study on Stability and Reactivity of 1-Aminocyclopropane-1-carboxylic Acid Amine Radical Cation
Authors: Ito Mika , Tokiwa Hiroaki 
Published: September 2007

Abstract
The stability and reactivity of the 1-aminocyclopropane-1-carboxylic acid (ACC) amine radical cation, which is a key intermediate of ethylene biosynthesis in plants, were examined by quantum chemical calculations. The local interactions to stabilize radical species were treated with a hydrated cluster. Potential energy curves were obtained for two types of reactions from ACC amine radical cation: (1) direct ring opening of ACC amine radical cation, followed by proton abstraction from the amino group, and (2) proton abstraction from the amino group, followed by ring opening of ACC aminyl radical. A remarkable difference was found in the ring-opening processes of reactions (1) and (2). Rate constants (k) of 6.10×1012 and 8.89×109 s−1 at 298.15 K were estimated for the ring openings of ACC amine radical cation and ACC aminyl radical, respectively, at the B3LYP/6-31+G(d,p) level, and were in agreement with experimental results. The ring opening of ACC amine radical cation was 103-fold faster than that of ACC aminyl radical with almost no barrier height. It was thus quantitatively demonstrated that reaction (1) was more favorable than reaction (2) for ethylene synthesis.
Hydration Structure of l-Hydrogenglutamate Ion in Concentrated Aqueous Solutions
Authors: Kameda Yasuo , Sasaki Motoya , Amo Yuko , Usuki Takeshi 
Published: September 2007

Abstract
Neutron diffraction measurements were carried out on 14N/15N isotopically substituted aqueous 5 mol % sodium l-hydrogenglutamate solutions in D2O in order to obtain direct information concerning the structure of the first hydration shell around the amino-group of the l-hydrogenglutamate ion. Hydration parameters were determined through the least-squares fitting analysis of the observed intermolecular difference function, ΔNinter(Q). It was shown that, on average, 3.1(1) D2O molecules were hydrogen-bonded to the amino-hydrogen atoms of the hydrogenglutamate ion with interatomic distances of rNOW=2.92(2) and rNDW=3.47(1) Å, respectively.
Calorimetric Finding of Phase and Glass Transitions Concerning the Ordering of the Water Located between the Silicate Layers of the Clay Na-RUB-18
Authors: Watanabe Keisuke , Oguni Masaharu 
Published: September 2007

Abstract
The behavior of the water accommodated between the silicate layers of a clay Na8[Si32O64(OH)8]·32H2O was investigated by using adiabatic calorimetry. A phase transition was observed showing a heat-capacity peak at 194 K and its entropy was roughly estimated to be 5.2 J K−1 (H2O-mol)−1. The transition was interpreted to be essentially due to an order–disorder process involving two orientations of the water molecule which can form hydrogen bonds with siloxane-oxygen atoms. It is thought that the water molecules move with a large amplitude of vibration as well as disorder between the two permissible orientations at room temperature and become gradually ordered to take a more stable orientation of the two below 194 K. A glass transition was found at a temperature Tg=106 K, due to freezing of the water molecule in the orientations, which causes a little disorder to remain. The potential barrier (Δεa) of the reorientation was assessed from the Tg to be about 34 kJ mol−1, which corresponds to the energy to break two hydrogen-bonds. There remains a possibility that the silanol-hydrogen atom takes a tunneling state involving two accessible sites between two silanol-oxygen atoms; however, it was not confirmed in this work.
Experimental Thermochemical Study of 6-Chloro-2,3-dimethylquinoxaline 1,4-Dioxide and DFT Evaluation of the N–O Bond Enthalpies in Related Haloquinoxalines
Authors: Gomes José R B , Vieira Mónica A A , Stovall Dawn M , Acree William E , Ribeiro da Silva Maria D M C 
Published: September 2007

Abstract
The standard molar enthalpy of formation at T=298.15 K of 6-chloro-2,3-dimethylquinoxaline 1,4-dioxide in the gas-phase was derived using the values of the enthalpies of combustion for the crystalline solid, measured by using rotating-bomb combustion calorimetry, and of the enthalpies of sublimation, measured by using Calvet microcalorimetry. This value was used for calibrating the computational procedure employed to estimate the gas-phase enthalpies of formation for the deoxygenated quinoxaline derivatives and also to compute the first, second, and mean (N–O) bond dissociation enthalpies in the gas-phase. The B3LYP/6-311+G(2d,2p) calculations were also extended to the fluorine, bromine, and iodine derivatives and to the isomers with a halogen substituted at position 5. When the halogen atom enters the same position in the quinoxaline ring, it was found that the substituent had almost no influence on the computed (N–O) bond dissociation enthalpies, except for 5-fluoro-2,3-dimethylquinoxaline 1,4-dioxide.
Solid-State Structures of trans-[RuCl2{Cl2PN(Me)N(Me)PCl2}2] and cis-[MCl2{Cl2PN(Me)N(Me)PCl2}] (M = PtII and PdII) Studied by X-ray Crystallography and 13C CPMAS NMR Spectroscopy
Authors: Takara Satoshi , Batsanov Andrei S , Schaffer Douglas J , Takase Michael , Kunishige Janice A , Lee Susan J 
Published: September 2007

Abstract
Solid-state structures of trans-[RuCl2{Cl2PN(Me)N(Me)PCl2}2] (1), cis-[PdCl2{Cl2PN(Me)N(Me)PCl2}] (2), and cis-[PtCl2{Cl2PN(Me)N(Me)PCl2}] (3) were studied by using 13C CPMAS NMR spectroscopy and X-ray crystallography. The ruthenium atom in 1 was on a crystallographic inversion center and had a slightly distorted octahedral coordination. 2 and 3 contained palladium and platinum atoms in a square-planar geometry, respectively. In 2, axial sites of the Pd atom were filled by intermolecular Pd···Cl contacts to form an infinite chain. Molecules of 3 pack in an edge-to-face manner and no obvious “axial” contacts at the Pt atom were observed. Different geometries of hydrazide nitrogens in 1, 2, and 3 were observed: in 1 and 2, one of the nitrogen atoms was trigonal planar and the other one was pyramidal; the two hydrazine nitrogen atoms in 3 had trigonal planar geometry. 13C CPMAS NMR spectra are consistent with X-ray data. The P–N distances are shorter than normally accepted P–N single bond lengths, suggesting a degree of P–N π bonding.
Convenient Synthesis of 3-Substituted Benzo[b]thiophenes by Iodine-Mediated Cyclization of α-Substituted 2-(1-Phenylethylthio)styrenes
Authors: Kobayashi Kazuhiro , Nakamura Daizo , Miyamoto Kazuna , Morikawa Osamu , Konishi Hisatoshi 
Published: September 2007

Abstract
A new and convenient method for the preparation of 3-substituted benzo[b]thiophenes was developed. α-Substituted 2-(1-phenylethylthio)styrenes, which could easily be prepared from 2-mercaptophenyl ketones or benzenethiols in two or three steps, respectively, underwent 5-endo cyclization on treatment with iodine in the presence of sodium hydrogencarbonate in acetonitrile at room temperature to give 3-substituted benzo[b]thiophenes in fair to good yields.
Conductive, Magnetic, and Optical Properties of Sterically Hindered Dodecithiophenes. Evidence for the Coexistence of Bipolaron and π-Dimer
Authors: Kurata Tomoyuki , Mohri Takashi , Takimiya Kazuo , Otsubo Tetsuo 
Published: September 2007

Abstract
Conductive, magnetic, and optical properties of sterically hindered dodecithiophenes bearing bulky 2,2-bis(butoxymethyl)-1,3-propanediyl groups were examined. At high doping with FeCl3, a completely hindered dodecithiophene had only a poor conductivity of 5×10−4 S cm−1, but two partially hindered dodecithiophenes had relatively high conductivities of 1.9 and 0.6 S cm−1, which are one or two orders lower than the conductivity (38 S cm−1) of the unhindered dodecithiophene. Despite having different structures and conductivities, all of the doped solids of these dodecithiophenes were magnetically inactive and demonstrated similar optical absorption spectra in the near infrared region, as generally observed for polythiophenes. On the other hand, their optical spectra in dichloromethane were quite different from one another. A solution spectrum of the unhindered dodecithiophene under high doping was characterized by two absorption transitions assignable to a π-dimer. On the other hand, a solution spectrum of the completely hindered dodecithiophene was characterized by an absorption transition due to a bipolaron. Furthermore, the solution spectra of two partially hindered dodecithiophenes could be explained as an overlap of both π-dimeric and bipolaronic bands. From these results, both π-dimer and bipolaron species appear to serve as active charge carriers in conductive poly(oligo)thiophenes.
Cationic Palladium Complex-Catalyzed Hydrosilylative Cross-Coupling of Alkynes with Alkenes. 1,4-Addition of Trichlorosilane to Form 4-Silyl-1-butene Framework
Authors: Shimamoto Takamitsu , Chimori Motoharu , Sogawa Hiroaki , Harada Yuki , Aoki Masaharu , Yamamoto Keiji 
Published: September 2007

Abstract
A new hydrosilylative cross-coupling reaction of a variety of alkynes with several alkenes, which is catalyzed by a cationic palladium complex A (1 mol %) without or with added PPh3 ligand, was studied systematically. The reaction using HSiCl3 as an addend afforded more or less two types of products consisting of four possible derivatives, R1CH=CR2–CHR3–CHR4–SiCl3, which always contained 4-trichlorosilyl-1-butene frameworks, in acceptable combined yields. The coupling pattern was dependent both on the precatalyst A in the absence or presence of PPh3 [also P(C6F5)3] and on the combination of the alkyne and alkene counterpart employed. A possible catalytic cycle that involves an initial hydropalladation of an alkyne, followed by a facile and specific carbopalladation of an alkene, is proposed. At the same time, the lack of regioselectivity in the latter step is noted. The effect of the added phosphine ligand on the coupling pattern is briefly discussed.
Photoisomerization Mechanism of All-Z-Oligo(phenylenevinylene)s
Authors: Ikegami Masashi , Nagao Masato , Katayama Hiroyuki , Ozawa Fumiyuki , Arai Tatsuo 
Published: September 2007

Abstract
Photoisomerization mechanism of para-substituted oligo(phenylenevinylene)s (OPVs) was dependent on the number of olefin units. While mono-olefin OPV1 underwent two-way photoisomerization, other OPVs (OPV2, OPV3, and OPV4) underwent photochemical one-way Z-to-E isomerization. As the number of olefin units increased, contribution of the triplet excited state to the Z-to-E isomerization becomes larger.