bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Enantiopure Chiral Amino‐[D1]methyllithium Compounds and Determination of Their Micro‐ and Macroscopic Configurational Stabilities
Authors: Kapeller Dagmar C. , Hammerschmidt Friedrich
Published: April 2009

The smaller the better: Enantiopure aminomethyllithiums, such as depicted, the smallest of their kind, have been prepared and tested for their micro‐ and macroscopic configurational stabilities, which are delicately influenced by R1 and R2. The species with R1=R2=Bn is macroscopically configurationally stable below −95 °C.

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Chiral amino‐[D1]methyllithiums have been tested with regard to their microscopic and macroscopic configurational stabilities. The N‐Boc‐N‐diethoxyphosphinyl‐substituted analogue immediately rearranged, showing complete retention of configuration at up to 0 °C. The N‐Boc‐N‐PMB‐protected analogue enantiomerized at −78 °C, but displayed an ee value of 65 % at −95 °C under macroscopic conditions when quenched with benzaldehyde seconds after its generation. Isocyanomethyllithium proved to be configurationally labile at this temperature and racemized completely, even on the microscopic timescale. Only the non‐stabilized N,N‐dibenzylaminomethyllithium was found to be virtually macroscopically configurationally stable below −95 °C.
Metathesis‐like Splitting Reactions of Metallated [36]Octaphyrins(1.1.1.1.1.1.1.1): Experimental and Computational Investigations
Authors: Tanaka Yasuo , Shinokubo Hiroshi , Yoshimura Yosuke , Osuka Atsuhiro
Published: April 2009

Do the splits! Metalation of [36]octaphyrin (1) and the metathesis‐like splitting behavior of 1–metal complexes were examined both experimentally and theoretically. Complexes 1–CuCu and 1–CoCu underwent quantitative splitting reactions into two metalloporphyrins, whereas 1–Cu, 1–Co, and 1–ZnZn did not show such reactivity.

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meso‐Octakis(pentafluorophenyl)‐substituted [36]octaphyrin(1.1.1.1.1.1.1.1) (1) is a figure‐of‐eight nonaromatic macrocycle that serves as a unique platform to induce a metathesis‐like splitting reaction upon bis‐CuII metalation. To get a better understanding of this splitting reaction, we examined the metalation of 1 with several metal ions. In contrast with the smooth and quantitative splitting reaction of bis‐CuII complex 1–CuCu, free‐base 1, mono‐CuII complex 1–Cu, and bis‐ZnII complex 1–ZnZn do not undergo the splitting reaction. Mono‐CoII complex 1–Co was selectively produced from metalation with the CoII ion, from which hybrid complex 1–CoCu was synthesized. The hybrid complex 1–CoCu undergoes the splitting reaction to give 2–Co and 2–Cu quantitatively. Activation parameters of the splitting reactions were determined: Ea=104 kJ mol−1, ΔH≠=101 kJ mol−1, ΔS≠=−25.0 J mol−1 K−1, and ΔV≠=18 cm3 mol−1 for 1–CuCu and Ea=105 kJ mol−1, ΔH≠=102 kJ mol−1, and ΔS≠=−29.9 J mol−1 K−1 for 1–CoCu. A marked difference between the splitting reaction reactivity of 1–CuCu and 1–ZnZn has been examined by DFT calculations at the B3LYP/631SDD//B3LYP/LANL2DZ level, which revealed that the reaction proceeds through a stepwise route involving initial C1C20 bond formation to give INT1 as the rate‐determining step and subsequent C21C40 bond formation to give a spirocyclobutane intermediate (INT2), followed by a radical reverse cycloaddition reaction to give two metalloporphyrins. Inherent instability of 1–CuCu, which may arise from its strongly distorted structure, was indicated to be a main factor in the smooth splitting reaction. Finally, a new bis‐PdII complex (5–PdPd) was isolated in the metalation of 1 with Pd(OAc)2 in a 9:1 mixture of 2,2,2‐trifluoroethanol and methanol as a manifestation of the transannular electronic interaction in metalated octaphyrin complexes. Collectively, these results underscore the importance of the transannular electronic interactions that are enhanced by metalation, depending upon the coordinated metal ions.
Cover Picture: Palladium‐Catalyzed Carbon–Carbon Bond Formation and Cleavage of Organo(hydro)fullerenes (Chem. Eur. J. 19/2009)
Authors: Nambo Masakazu , Itami Kenichiro
Published: April 2009

An unexpected CH bond dimerization reaction and CC bond‐cleavage reaction in organo(hydro)fullerenes have been discovered. In their Communication on page 4760 ff., K. Itami and M. Nambo describe the use of Pd catalysts for a number of interesting reactions of such fullerenes.

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Excision is indicated for intraductal papilloma of the breast diagnosed on core needle biopsy
Authors: Jaffer Shabnam , Nagi Chandandeep , Bleiweiss Ira J.
Published: April 2009

BACKGROUND:

Although it has been accepted that intraductal papillomas with atypia or malignancy diagnosed on core needle biopsy require surgical excision, the management of pure intraductal papillomas has been controversial. Because some series reported a small but definite incidence of atypia or malignancy, whereas others claimed that radiologic follow‐up was adequate, this study evaluated results of excision of all pure intraductal papillomas diagnosed on core needle biopsy at this institution.

METHODS:

By using computerized pathology files from January of 2000 to December of 2004, 200 cases of intraductal papillomas on core needle biopsy were identified. Information regarding excision was available in 104 cases. All specimens were reviewed to confirm both the diagnoses as well as the presence of biopsy site changes in excision specimens, and the findings were correlated with radiologic data.

RESULTS:

The age of the patients ranged from 25 to 82 years (mean, 55.5). The diagnoses on excision were as follows: intraductal papillomas = 71 cases (68.3%), no residual intraductal papillomas = 16 (15.3%), atypical duct hyperplasia = 8 (7.7%), ductal carcinoma in situ = 6 (5.8%), and invasive carcinoma = 3 (2.9%). In cases with atypia or malignancy, these findings were adjacent to but not in the biopsy site. In cases with atypical duct hyperplasia or ductal carcinoma in situ, a spectrum of histologic changes ranging from florid to atypical duct hyperplasia (14 cases), to ductal carcinoma in situ (6 cases) were present, all involving intraductal papillomas.

CONCLUSIONS:

The upstage rate of pure intraductal papillomas on core needle biopsy to atypia or malignancy on excision was 16.4%. Because of sampling error and the close proximity of atypia or malignancy to the intraductal papillomas (suggesting precancerous potential), excision was recommended of these lesions diagnosed on core needle biopsy. Close radiologic‐pathologic correlation was important in the evaluation of these lesions. Cancer 2009. © 2009 American Cancer Society.
Change in health‐related quality of life of newly diagnosed cancer patients, cancer survivors, and controls*
Authors: Baker Frank , Denniston Maxine , Haffer Samuel C. , Liberatos Penny
Published: April 2009

BACKGROUND:

Data from the 1998 Health Outcomes Survey (HOS) of patients who were enrolled in Medicare managed care and follow‐up data from the 2000 HOS resurvey were analyzed to examine changes in health‐related quality of life (HRQOL) of newly diagnosed cancer patients, cancer survivors, and patients without cancer.

METHODS:

In 1998, the HOS was mailed to a random sample of 279,135 beneficiaries, and 167,096 respondents (60%) returned completed surveys. Those who were diagnosed with cancer (22,747) were frequency age‐matched to an equal number of patients with no cancer. In 2000, the HOS was mailed to the same cohort of beneficiaries. Complete data at both baseline and follow‐up were available on 16,850 individuals for inclusion in the current study.

RESULTS:

After 2 years, respondents who had been diagnosed with cancer at baseline continued to have lower scores on all but 3 scales of the 36‐item short‐form HRQOL measure. However, there was no evidence that they were declining any faster than or catching up with noncancer patients. Those who had been newly diagnosed with cancer since the baseline survey had lower mean scale scores than the no‐cancer group on all scales and lower mean scores than the cancer survivors on all subscales except Bodily Pain, Vitality, and Mental Health.

CONCLUSIONS:

This study demonstrated that, after 2 years, cancer survivors continued to have poorer HRQOL than the no‐cancer group. Newly diagnosed cancer patients had poorer quality of life than both the longer term cancer survivors and the no‐cancer group. Cancer 2009. Published 2009 by the American Cancer Society*.
Phase 1 trial of temozolomide plus irinotecan plus O6‐benzylguanine in adults with recurrent malignant glioma
Authors: Quinn Jennifer A. , Jiang Sara Xiaoyin , Reardon David A. , Desjardins Annick , Vredenburgh James J. , Gururangan Sridharan , Sampson John H. , McLendon Roger E. , Herndon James E. , Friedman Henry S.
Published: April 2009

BACKGROUND:

The current study was a phase 1 clinical trial conducted with patients who had recurrent or progressive malignant glioma (MG). The trial was designed to determine the maximum tolerated dose (MTD) and toxicity of irinotecan (CPT‐11) when administered with temozolomide (TMZ) and O6‐benzylguanine (O6‐BG).

METHODS:

All 3 drugs, CPT‐11, TMZ, and O6‐BG, were administered on Day 1 of a 21‐day treatment. First, patients were treated with a 1‐hour bolus infusion of O6‐BG at a dose of 120 mg/m2 followed immediately by a 48‐hour continuous infusion of O6‐BG at a dose of 30 mg/m2/d. Second, within 60 minutes of the end of the 1‐hour bolus infusion of O6‐BG, TMZ was administered orally at a dose of 355 mg/m2. Third, 1 hour after administration of TMZ, CPT‐11 was infused over 90 minutes. Patients were accrued to 1 of 2 strata based on CYP3A1‐ and CYP3A4‐inducing antiepileptic drug (EIAED) use; dose escalation was conducted independently within these strata.

RESULTS:

Fifty‐five patients were enrolled. In both strata, the dose‐limiting toxicities were hematologic and included grade 4 neutropenia, febrile neutropenia, leukopenia, and/or thrombocytopenia. For Stratum 1 (EIAEDs), when TMZ was administered at a dose of 355 mg/m2, the MTD of CPT‐11 was determined to be 120 mg/m2. In contrast, for Stratum 2 (no EIAEDs), when TMZ was administered at a dose of 200 mg/m2, the MTD of CPT‐11 was determined to be 80 mg/m2.

CONCLUSIONS:

The authors believe that the results of the current study provide the foundation for a phase 2 trial of O6‐BG in combination with CPT‐11 and TMZ in patients with MG. Cancer 2009. © 2009 American Cancer Society.
Natural history, growth kinetics, and outcomes of untreated clinically localized renal tumors under active surveillance
Authors: Crispen Paul L. , Viterbo Rosalia , Boorjian Stephen A. , Greenberg Richard E. , Chen David Y. T. , Uzzo Robert G.
Published: April 2009

BACKGROUND:

The growth kinetics of untreated solid organ malignancies are not defined. Radiographic active surveillance (AS) of renal tumors in patients unfit or unwilling to undergo intervention provides an opportunity to quantify the natural history of untreated localized tumors. The authors report the radiographic growth kinetics of renal neoplasms during a period of surveillance.

METHODS:

The authors identified patients with enhancing renal masses who were radiographically observed for at least 12 months. Clinical and pathological records were reviewed to determine tumor growth kinetics and clinical outcomes. Tumor growth kinetics were expressed in terms of absolute and relative linear and volumetric growth.

RESULTS:

The authors identified 172 renal tumors in 154 patients under AS. Median tumor diameter and volume on presentation were 2.0 cm (mean, 2.5; range, 0.4‐12.0) and 4.18 cm3 (mean, 20.0; range, 0.033‐904). Median duration of follow‐up was 24 months (mean, 31; range, 12‐156). A significant association between presenting tumor size and proportional growth was noted, with smaller tumors growing faster than larger tumors. Thirty‐nine percent (68 of 173) of tumors underwent delayed intervention, and 84% (57 of 68) were pathologically malignant. Progression to metastatic disease was noted in 1.3% (2 of 154) of patients.

CONCLUSIONS:

The authors demonstrated the association between a tumor's volume and subsequent growth, with smaller tumors exhibiting significantly faster volumetric growth than larger tumors, consistent with Gompertzian kinetics. Surveillance of localized renal tumors is associated with a low rate of disease progression in the intermediate term, and suggests potential overtreatment biases in select patients. Cancer 2009. © 2009 American Cancer Society.
High‐dose chemotherapy and autologous hematopoietic progenitor cell rescue in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors
Authors: Butturini Anna M. , Jacob Mary , Aguajo Jennifer , Vander‐Walde Noam A. , Villablanca Judy , Jubran Rima , Erdreich‐Epstein Anat , Marachelian Araz , Dhall Girish , Finlay Jonathan L.
Published: April 2009

BACKGROUND:

The role of myeloablative chemotherapy in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors (MB/ST‐PNET) is controversial, in particular in patients who develop recurrent disease after craniospinal radiotherapy.

METHODS:

In this retrospective analysis, the authors investigated the outcome of children with recurrent MB/ST‐PNET who were referred for myeloablative chemotherapy and autologous hematopoietic progenitor cell rescue at Childrens Hospital Los Angeles.

RESULTS:

Thirty‐three children were referred for myeloablative chemotherapy: Fourteen of those children were never transplanted because of pre‐transplant adverse events, and 19, including 6 without and 13 with previous irradiation, underwent transplant. Conditioning regimens included a backbone of thiotepa, which was given either in a single cycle or in multiple sequential cycles. The 3‐year post‐transplant event‐free survival rate in unirradiated versus previously irradiated children was 83% ± 15% versus 20% ± 12%, respectively (P = .04). One child who had never been exposed to radiotherapy died of toxicity; the other children received post‐transplant radiotherapy and remained disease free. Nine previously irradiated children experienced 4 toxic deaths and 6 tumor recurrences (1 patient had both): An interval of <1 year between initial radiotherapy and myeloablative chemotherapy predicted a greater risk of toxic death (P = .02), whereas a history of meningeal metastases at diagnosis and a poor response to the initial rescue therapy predicted a greater risk of post‐transplant recurrence (P = .03 and P = .08, respectively).

CONCLUSIONS:

Myeloablative doses of thiotepa‐based chemotherapy and radiotherapy were able to cure most children who had radiotherapy‐naive, chemoresponsive recurrences. Children who developed recurrences after craniospinal radiotherapy had poorer outcomes; however, cure was possible in those who had good prognostic features at presentation, chemoresponsive recurrences, and a long interval between initial radiotherapy and myeloablative chemotherapy. Cancer 2009. © 2009 American Cancer Society.
Brief guidance document on the appropriate use of human papillomavirus testing issued by the Cytology Education and Technology Consortium
Authors: Birdsong George G.
Published: April 2009

A brief, easy‒to‒use guidance document regarding the appropriate use of human papillomavirus (HPV) testing has been released by the Cytology Education and Technology Consortium. Use of this document will help in preventing unnecessary or inappropriate HPV testing.
Quenched large deviations for random walk in a random environment
Authors: Yilmaz Atilla
Published: April 2009

We take the point of view of a particle performing random walk with bounded jumps on ℤd in a stationary and ergodic random environment. We prove the quenched large‐deviation principle (LDP) for the pair empirical measure of the so‐called environment Markov chain. By an appropriate contraction, we deduce the quenched LDP for the mean velocity of the particle and obtain a variational formula for the corresponding rate function. We propose an ansatz for the minimizer of this formula. When d = 1, we verify this ansatz and generalize the nearest‐neighbor result of Comets, Gantert, and Zeitouni to walks with bounded jumps. © 2009 Wiley Periodicals, Inc.
Experimental comparison of phase‐noise in cross‐coupled RC‐ and LC‐oscillators
Authors: Oliveira Luis Bica , Allam Ahmed , Filanovsky Igor M. , Fernandes Jorge R. , Verhoeven Chris J. M. , Silva Manuel M.
Published: April 2009

Relaxation RC‐oscillators are notorious for their poor phase‐noise performance. However, there are reasons to expect a phase‐noise reduction in quadrature oscillators obtained by cross‐coupling two relaxation oscillators. We present measurements on 5 GHz oscillators, which show that in RC‐oscillators the coupling reduces both the phase‐noise and quadrature error, whereas in LC‐oscillators the coupling reduces the quadrature error, but increases the phase‐noise. A comparison using standard figures of merit indicates that quadrature RC‐oscillators may be a viable alternative to LC‐oscillators when area and cost are to be minimized. Copyright © 2009 John Wiley & Sons, Ltd.
A single‐stage phase‐shifted full‐bridge AC/DC converter with variable frequency control
Authors: Chiu Huang‐Jen , Lo Yu‐Kang , Lee Ting‐Peng , Chuang Ching‐Chun , Mou Shann‐Chyi
Published: April 2009

This letter presents a single‐stage soft‐switched full‐bridge AC/DC converter for low‐voltage/high‐current output applications. A phase‐shifted method with a variable frequency control is used to regulate the DC bus voltage and the output voltage of the single‐stage AC/DC converter. The proposed circuit topology and control scheme exhibit superior performances (i.e. high power factor, high‐efficiency, and ring‐free features). Correspondingly, a laboratory prototype, 500 W 5V/100A AC/DC converter, is implemented to verify the feasibility of the proposed design. Copyright © 2009 John Wiley & Sons, Ltd.
Capacity lower bound and energy efficiency of training‐based MIMO systems over correlated channels
Authors: Pang Jiyong , Li Jiandong , Jin Shan
Published: April 2009

The behavior of training‐based multiple‐input multiple‐output wireless communications over correlated channels is studied in the low signal‐to‐noise ratio (SNR) regime from an energy efficiency perspective. To start with, a relaxed but analytically more tractable capacity lower bound is derived where the impacts of channel spatial correlation are considered simply through the ranks of correlation matrices. It shows that, different from the independent and identically distributed case, the optimal training length no longer equals the number of transmit antennas but is just the same as the rank of transmit correlation matrix. Next, the bit energy requirements are analyzed based on the derived capacity lower bound. It shows that the minimum bit energy required for reliable communication is achieved at a nonzero SNR value below, which the bit energy grows to infinity with a zero‐approaching wideband slope. Flash training and transmission scheme is also studied and shown to improve the energy efficiency. In addition, the impacts of spatial correlation, channel coherence interval and antenna number on the energy efficiency are analyzed. It shows that stronger spatial correlation leads to less bit energy, i.e. higher‐energy efficiency. The minimum bit energy is achieved at lower SNR in a more correlated channel. Spatial correlation also helps to reduce the signal peakiness in the flash scheme. And larger coherence interval always improves energy efficiency at all SNR. Finally, the validity of the proposed results is verified by numerical simulations. Copyright © 2009 John Wiley & Sons, Ltd.
Mechanistic Information on CuII Metalation and Transmetalation of Chlorophylls
Authors: Orzeł Łukasz , van Eldik Rudi , Fiedor Leszek , Stochel Grażyna
Published: April 2009

Chlorophyll a and pheophytin a have been treated with various metal salts in solution. As a result, metallo derivatives of photosynthetic pigments were formed, or the chlorine ring was oxidized. These studies showed that both effects can be caused by CuII ions depending on the redox potential of its complexes formed in specific media. In this report the results of studies on metal insertion and exchange reactions are presented. According to the common use of the “acetate method” in the synthesis of metallotetrapyrroles, and the fact that acetates coordinated to CuII ions protect chlorophylls from oxidative degradation, CuII acetate monohydrate was selected as main reagent. The metalation and transmetalation processes were investigated with spectroscopic (UV/Vis absorption and emission) and kinetic (conventional and high‐pressure) techniques. It turned out that differences in solvent properties can significantly affect not only the rates (metalation), but also the course (transmetalation) of the reaction. The most pronounced effect was found for the transmetalation reaction in acetonitrile, which was terminated at the very initial stage. As shown elsewhere, some special agents/factors, such as excess of acetate, are required to facilitate the dissociation of Mg2+ and to push the reaction forward towards formation of the CuII derivative of chlorophyll. The mechanisms of two other reactions are proposed on the basis of the determined activation parameters, which correspond to the general mechanisms for metalation and transmetalation of tetrapyrroles with sitting‐atop and bimetallic intermediates, respectively. The bimetallic complex of chlorophyll in methanol is probably the most stable complex of this type observed ever. It confirms that spontaneous exchange of Mg2+ by CuII occurring in plants must result from specific conditions and/or involve contribution from other components of the photosystem.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Potentiometric, Spectroscopic and DFT Study of the VIVO Complexes Formed by Di(pyridin‐2‐yl) Ligands
Authors: Pisano Luisa , Kiss Dóra , Várnagy Katalin , Sanna Daniele , Micera Giovanni , Garribba Eugenio
Published: April 2009

The coordinating properties of a series of di(pyridin‐2‐yl) derivatives towards the VIVO2+ ion have been studied through the combined application of potentiometric and spectroscopic (electronic absorption and EPR spectroscopies) methods. In particular, di(pyridin‐2‐yl)amine (DPA), di(pyridin‐2‐yl)methane (DPM), di(pyridin‐2‐yl) ketone (DPK), di(pyridin‐2‐yl)methanol (DPMO), 2‐acetylpyridine (2‐AP) and 2‐hydroxymethylpyridine (2‐HMP), and two amino acid derivatives of di(pyridin‐2‐yl)methylamine (DPMA), namely N‐glycyl‐DPMA and N‐histidyl‐DPMA, have been examined. The stability constants of proton and VIVO complexes (logβ) were measured at 25 °C and at a constant ionic strength of 0.2 M (KCl). The results show that the simple di(pyridin‐2‐yl) derivatives having only pyridine nitrogen atoms form mono‐chelated species with the (Npyr, Npyr) donor set, whereas those provided with carbonyl or hydroxy groups form mono‐ and bis‐chelated complexes with (Npyr, CO) or (Npyr, O–) coordination. The square pyramidal species with 2×(Npyr, O–) coordination exists in equilibrium with the octahedral isomer, which has an axially bound water molecule and is characterized by an anomalously low value of the 51V hyperfine coupling constant along the z‐axis (Az). DFT calculations were used to optimize the geometry of the complexes and to predict the Az values measured in the EPR spectra for the penta‐ and hexacoordinate complexes formed by DPK, DPMO, 2‐AP and 2‐HMP and for the [VOLH–1]+ and[VOLH–2] species formed by the amino acid derivatives of DPMA. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Dependence of DNA double strand break repair pathways on cell cycle phase in human lymphoblastoid cells
Authors: Takashima Yoshio , Sakuraba Mayumi , Koizumi Tomoko , Sakamoto Hiroko , Hayashi Makoto , Honma Masamitsu
Published: April 2009

DNA double‐strand breaks (DSBs) are usually repaired by nonhomologous end‐joining (NHEJ) or homologous recombination (HR). NHEJ is thought to be the predominant pathway operating in mammalian cells functioning in all phases of the cell cycle, while HR works in the late‐S and G2 phases. However, relative contribution, competition, and dependence on cell cycle phases are not fully understood. We previously developed a system to trace the fate of DSBs in the human genome by introducing the homing endonuclease I‐SceI site into the thymidine kinase (TK) gene of human lymphoblastoid TK6 cells. Here, we use this system to investigate the relative contribution of HR and NHEJ for repairing I‐SceI‐induced DSBs under various conditions. We used a novel transfection system, Amaxa™ nucleofector, which directly introduces the I‐SceI expression vector into cell nuclei. Approximately 65% of transfected cells expressed the I‐SceI enzyme and over 50% of the cells produced a single DSB in the genome. The relative contribution of NHEJ and HR for repairing the DSB was ∼100:1 and did not change with transfection efficiency. Cotransfection with KU80‐siRNA significantly diminished KU80 protein levels and decreased NHEJ activity, but did not increase HR. We also investigated HR and NHEJ in synchronized cells. The HR frequency was 2–3 times higher in late‐S/G2 phases than in G1, whereas NHEJ was unaffected. Even in late‐S/G2 phases, NHEJ remained elevated relative to HR. Therefore, NHEJ is the major pathway for repairing endonuclease‐induced DSBs in mammalian cells even in late‐S/G2 phase, and does not compete with HR. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.
The functional significance of centrosomes in mammalian meiosis, fertilization, development, nuclear transfer, and stem cell differentiation
Authors: Schatten Heide , Sun Qing‐Yuan
Published: April 2009

Centrosomes had been discovered in germ cells and germ cells continue to provide excellent but also challenging material in which to study complex centrosomal dynamics. The present review highlights the importance of centrosomes for meiotic spindle integrity and the susceptibility of meiotic spindle centrosomes to aging and drugs or toxic agents which may be associated with female infertility, aneuploidy, and developmental abnormalities. We discuss cell and molecular aspects of centrosomes during fertilization, a critical stage in which centrosomes play crucial roles in precisely organizing the sperm aster that allows apposition of male and female genomes followed by formation of the zygote aster that is important for the formation of the bipolar spindle apparatus during cell division. Development of an embryo involves sequential cell divisions in which centrosomes play a critical role in establishing asymmetry that allows differentiation of cells and targeted signal transductions for the developing embryo. Asymmetric centrosome dynamics are also critical for stem cell division to maintain one daughter cell as a stem cell while the other daughter cell undergoes centrosome growth in preparation for differentiation. This review also discusses the complex interactions of somatic cell centrosomes with the recipient oocyte in reconstructed (cloned) embryos in which centrosome remodeling is crucial to fulfill functions that are carried out by the zygote centrosome in fertilized eggs. We close our discussion with a look at centrosome dysfunctions and implications for male fertility and assisted reproduction. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.
Evaluation of genome damage and its relation to oxidative stress induced by glyphosate in human lymphocytes in vitro
Authors: Mladinic Marin , Berend Suzana , Vrdoljak Ana Lucic , Kopjar Nevenka , Radic Bozica , Zeljezic Davor
Published: April 2009

In the present study we evaluated the genotoxic and oxidative potential of glyphosate on human lymphocytes at concentrations likely to be encountered in residential and occupational exposure. Testing was done with and without metabolic activation (S9). Ferric‐reducing ability of plasma (FRAP), thiobarbituric acid reactive substances (TBARS) and the hOGG1 modified comet assay were used to measure glyphosate's oxidative potential and its impact on DNA. Genotoxicity was evaluated by alkaline comet and analysis of micronuclei and other nuclear instabilities applying centromere probes. The alkaline comet assay showed significantly increased tail length (20.39 μm) and intensity (2.19%) for 580 μg/ml, and increased tail intensity (1.88%) at 92.8 μg/ml, compared to control values of 18.15 μm for tail length and 1.14% for tail intensity. With S9, tail length was significantly increased for all concentrations tested: 3.5, 92.8, and 580 μg/ml. Using the hOGG1 comet assay, a significant increase in tail intensity was observed at 2.91 μg/ml with S9 and 580 μg/ml without S9. Without S9, the frequency of micronuclei, nuclear buds and nucleoplasmic bridges slightly increased at concentrations 3.5 μg/ml and higher. The presence of S9 significantly elevated the frequency of nuclear instabilities only for 580 μg/ml. FRAP values slightly increased only at 580 μg/ml regardless of metabolic activation, while TBARS values increased significantly. Since for any of the assays applied, no clear dose‐dependent effect was observed, it indicates that glyphosate in concentrations relevant to human exposure do not pose significant health risk. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.
Sediment storage and transport in Pancho Rico Valley during and after the Pleistocene‐Holocene transition, Coast Ranges of central California (Monterey County)
Authors: García Antonio F. , Mahan Shannon A.
Published: April 2009

Factors influencing sediment transport and storage within the 156·6 km2 drainage basin of Pancho Rico Creek (PRC), and sediment transport from the PRC drainage basin to its c. 11 000 km2 mainstem drainage (Salinas River) are investigated. Numeric age estimates are determined by optically stimulated luminescence (OSL) dating on quartz grains from three sediment samples collected from a ‘quaternary terrace a (Qta)’ PRC terrace/PRC‐tributary fan sequence, which consists dominantly of debris flow deposits overlying fluvial sediments. OSL dating results, morphometric analyses of topography, and field results indicate that the stormy climate of the Pleistocene‐Holocene transition caused intense debris‐flow erosion of PRC‐tributary valleys. However, during that time, the PRC channel was backfilled by Qta sediment, which indicates that there was insufficient discharge in PRC to transport the sediment load produced by tributary‐valley denudation. Locally, Salinas Valley alluvial stratigraphy lacks any record of hillslope erosion occurring during the Pleistocene‐Holocene transition, in that the alluvial fan formed where PRC enters the Salinas Valley lacks lobes correlative to Qta. This indicates that sediment stripped from PRC tributaries was mostly trapped in Pancho Rico Valley despite the relatively moist climate of the Pleistocene‐Holocene transition.

Incision into Qta did not occur until PRC enlarged its drainage basin by c. 50% through capture of the upper part of San Lorenzo Creek, which occurred some time after the Pleistocene‐Holocene transition. During the relatively dry Holocene, PRC incision through Qta and into bedrock, as well as delivery of sediment to the San Ardo Fan, were facilitated by the discharge increase associated with stream‐capture. The influence of multiple mechanisms on sediment storage and transport in the Pancho Rico Valley‐Salinas Valley system exemplifies the complexity that (in some instances) must be recognized in order to correctly interpret terrestrial sedimentary sequences in tectonically active areas. Copyright © 2009 John Wiley & Sons, Ltd.
Reducing the peak and average power for OFDM systems using QAM by constellation shaping
Authors: Sterian Corneliu Eugen D. , Wesolowski Krzysztof , Wu Yi , Pätzold Matthias
Published: April 2009

In this paper, we present a shell mapping scheme to reduce the peak and average power of orthogonal frequency division multiplexing (OFDM) signals using quadrature amplitude modulation (QAM) by constellation shaping. Our approach can be considered as an extension of the shell mapping technique introduced originally in the V.34 recommendation of ITU‐T. The shell mapping method uses multiple cost functions, each having the OFDM block lengthNas a parameter. The cost functions are presented in closed form for anyN. The main advantage of the proposed scheme is that the peak and average power can be reduced without sacrificing the data rate, and no side information is needed at the receive side. We apply our constellation shaping technique to OFDM systems withNequal to 16, 32 and 128 subcarriers. The results show that the peak and average power decrease with increasing values ofN. This advantage is partly offset by a slightly higher system complexity. Copyright © 2009 John Wiley & Sons, Ltd.
Interaction of a phosphorus‐based FR, a nanoclay and PA6—Part 1: Interaction of FR and nanoclay
Authors: Ramani Alwar , Hagen Martin , Hereid Johan , Zhang Jianping , Bakirtzis Dimitri , Delichatsios Michael
Published: April 2009

The thermal decomposition of organophosphorus fire‐retardant (OP1311) and/ or organonanoclay (Cloisite 30B) is hereby investigated employing thermogravimetric analysis (TGA), to give an insight into their intrinsic behaviour and interaction in polymer nanocomposites for fire safety applications, because the addition of OP1311 and Cloisite 30B in Polyamide 6 (PA6) seems to have a synergistic effect on the thermal decomposition of PA6 (part 2 of the paper). An important objective of this research was to determine to what extent phosphorus components escape in the gaseous phase, which will affect the heat of combustion of the fire‐retarded polymer. The decomposition products arising from pyrolysis and combustion are investigated by means of Fourier transform infrared spectroscopy. Under pyrolytic conditions, the inclusion of Cloisite 30B into OP1311 (FR) shows a synergistic effect on the initial mass loss at low temperature of ∼280–420°C and leads to the acceleration of the thermal degradation process. While the DTG curve of Cloisite 30B shows two distinct degradation peaks (steps) that of OP1311 and OP1311 plus Cloisite 30B show four degradation steps. TGA measurements of OP1311 in nitrogen show more mass loss than in air, whereas Cloisite 30B gives similar amounts of mass loss in air and nitrogen. In nitrogen, the major evolved gaseous species from Cloisite 30B alone are hydrocarbons, 2‐(diethylamino)ethanol and water, whereas the evolved gases from that of OP1311 at ∼320°C are mainly water, at ∼420°C, carbon dioxide, water and ammonia and at 480–570°C diethylphosphinic acid. Under thermo‐oxidative conditions, the gases evolved are mainly carbon dioxide and water from both Cloisite 30B and OP1311. Copyright © 2009 John Wiley & Sons, Ltd.
On the stability and dissipation of wall boundary conditions for compressible flows
Authors: Lamarque N. , Porta M. , Nicoud F. , Poinsot T.
Published: April 2009

Characteristic formulations for boundary conditions have demonstrated their effectiveness to handle inlets and outlets, especially to avoid acoustic wave reflections. At walls, however, most authors use simple Dirichlet or Neumann boundary conditions, where the normal velocity (or pressure gradient) is set to zero. This paper demonstrates that there are significant differences between characteristic and Dirichlet methods at a wall and that simulations are more stable when using walls modelled with a characteristic wave decomposition. The derivation of characteristic methods yields an additional boundary term in the continuity equation, which explains their increased stability. This term also allows to handle the two acoustic waves going towards and away from the wall in a consistent manner. Those observations are confirmed by stability matrix analysis and one‐ and two‐dimensional simulations of acoustic modes in cavities. Copyright © 2009 John Wiley & Sons, Ltd.
Gefitinib ‐ a potential new treatment option in lung cancer
Authors: Blackhall Fiona , Chaplin Steve
Published: April 2009

Lung cancer is the second most common cancer in the UK, accounting for one in seven new cases, 24% of cancer deaths among men and 20% among women.1 In this article, Dr Fiona Blackhall and Steve Chaplin consider the use of gefitinib for lung cancer its mechanism of action, efficacy and adverse effects are described, followed by its effect on quality of life and its potential place in disease management. Pharmacist Geoff Saunders provides a commentary on the article and remarks on the selective use of gefitinib in lung cancer therapy. Copyright © 2009 John Wiley & Sons, Ltd.
Agomelatine: a new treatment for depression
Authors: Deakin Bill
Published: April 2009

It is estimated that depression carries the greatest burden of disability in established economies. A range of treatments are available, and selective serotonin reuptake inhibitors (SSRIs) are currently the most commonly prescribed class of antidepressant. In this article, the author discusses agomelatine, a novel antidepressant recently licensed by the European Medicines Agency (EMEA), the evidence for its use, and its potential place in therapy. Copyright © 2009 John Wiley & Sons, Ltd.
Calcium aluminate coated and uncoated free form fabricated CoCr implants: A comparative study in rabbit
Authors: Palmquist A. , Jarmar T. , Hermansson L. , Emanuelsson L. , Taylor A. , Taylor M. , Engqvist H. , Thomsen P.
Published: April 2009

The purpose of this study was to compare the integration in bone of uncoated free form fabricated cobalt chromium (CoCr) implants to the same implant with a calcium aluminate coating. The implants of cylindrical design with a pyramidal surface structure were press‐fit into the limbs of New Zealand white rabbits. After 6 weeks, the rabbits were sacrificed, and samples were retrieved and embedded. Ground sections were subjected to histological analysis and histomorphometry. The section counter part was used for preparing an electron transparent transmission electron microscopy sample by focused ion beam milling. Calcium aluminate dip coating provided a significantly greater degree of bone contact than that of the native CoCr. The gibbsite hydrate formed in the hardening reaction of the calcium aluminate was found to be the exclusive crystalline phase material in direct contact with bone. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
A study on the influence of biocompatible composites with bioactive ligands toward their effect on cell adhesion and growth for the application in bone tissue engineering
Authors: Roeker Stefanie , Böhm Stefanie , Diederichs Solvig , Bode Franziska , Quade Antje , Korzhikov Victor , van Griensven Martijn , Tennikova Tatiana B. , Kasper Cornelia
Published: April 2009

The aim of this study was the transformation of the macroporous zirconium dioxide ceramic Sponceram® into a biomimetic composite material. To enhance the adhesion of cells and to induce their differentiation into osteoblasts poly‐L‐lysine and BMP‐2 were coupled to polymers and copolymers based on 2‐deoxy‐N‐methacrylamido‐D‐glucose (ox.p(MAG) and p(MVA)) used as spacer, which were adsorbed onto the ceramic surface. The development of the composite materials was validated step by step qualitatively and quantitatively. The bioactive potential of the composite materials was tested under static and dynamic conditions using an osteoblastic model cell line and human mesenchymal stem cells. Both composite materials showed potential to enhance the adhesion of cells in the first 10 days of their cultivation. One of the composite materials, namely Sponceram®/ox.p(MAG)‐BMP‐2, was tested into a rotating‐bed bioreactor with regard to its osteogenic differentiation‐inducing potential. Compared with Sponceram® modified with BMP‐2 without a polymer spacer, it showed increased expression of osteogenic markers determined by PCR analysis. In summary, the in vitro testing of the developed composite materials demonstrated a promising potential for their application as biomimetic scaffold materials with controllable properties. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Comparative analysis of the performance of commonly available density functionals in the determination of geometrical parameters for zinc complexes
Authors: Sousa Sérgio F. , Carvalho Emanuela S. , Ferreira Diana M. , Tavares Isabel S. , Fernandes Pedro A. , Ramos Maria João , Gomes JosÉ A. N. F.
Published: April 2009

A set of 44 Zinc‐ligand bond‐lengths and of 60 ligand‐metal‐ligand bond angles from 10 diverse transition‐metal complexes, representative of the coordination spheres of typical biological Zn systems, were used to evaluate the performance of a total of 18 commonly available density functionals in geometry determination. Five different basis sets were considered for each density functional, namely two all‐electron basis sets (a double‐zeta and triple‐zeta formulation) and three basis sets including popular types of effective‐core potentials: Los Alamos, Steven‐Basch‐Krauss, and Stuttgart‐Dresden. The results show that there are presently several better alternatives to the popular B3LYP density functional for the determination of Zn‐ligand bond‐lengths and angles. BB1K, MPWB1K, MPW1K, B97‐2 and TPSS are suggested as the strongest alternatives for this effect presently available in most computational chemistry software packages. In addition, the results show that the use of effective‐core potentials (in particular Stuttgart‐Dresden) has a very limited impact, in terms of accuracy, in the determination of metal‐ligand bond‐lengths and angles in Zinc‐complexes, and is a good and safe alternative to the use of an all‐electron basis set such as 6‐31G(d) or 6‐311G(d,p). © 2009 Wiley Periodicals, Inc. J Comput Chem 2009
Hydrogenation of m‐dinitrobenzene to m‐phenylenediamine over La2O3‐promoted Ni/SiO2 catalysts
Authors: Liu Yingxin , Wei Zuojun , Deng Shuguang , Zhang Jiyan
Published: April 2009

BACKGROUND: Liquid‐phase catalytic hydrogenation of m‐dinitrobenzene is an environmentally friendly routine for m‐phenylenediamine production. The key to increasing product yield is to develop catalysts with high catalytic performance. In this work, La2O3‐modified Ni/SiO2 catalysts were prepared and applied to the hydrogenation of m‐dinitrobenzene to m‐phenylenediamine. The effect of La2O3 loading on the properties of Ni/SiO2 was investigated. The reaction kinetic study was performed in ethanol over Ni/3%La2O3–SiO2 catalyst, in order to clarify the reaction mechanism of m‐dinitrobenzene hydrogenation.

RESULTS: It was found that the activity of the silica supported nickel catalysts is obviously influenced by La2O3 loading. Ni/3%La2O3–SiO2 catalyst exhibits high activity owing to its well dispersed nickel species, with conversion of m‐dinitrobenzene and yield of m‐phenylenediamine up to 97.1% and 94%, respectively. The results also show that Ni/3%La2O3–SiO2 catalyst can be reused at least six times without significant loss of activity.

CONCLUSION: La2O3 shows strong promotion of the effect of Ni/SiO2 catalyst for liquid‐phase hydrogenation of m‐dinitrobenzene. La2O3 loading can affect the properties of Ni/SiO2 catalyst. Based on the study of m‐dinitrobenzene hydrogenation kinetics over Ni/3%La2O3–SiO2 catalyst, a possible reaction mechanism is proposed. Copyright © 2009 Society of Chemical Industry
Retracted:Effluent treatment using a bipolar electrochemical reactor with rotating cylinder electrodes of woven‐wire meshes
Authors: Grau Javier M. , Bisang José M.
Published: April 2009

The following article from the Journal of Chemical Technology and Biotechnology, ‘Effluent treatment using a bipolar electrochemical reactor with rotating cylinder electrodes of woven‐wire meshes’ by Javier M. Grau and José M. Bisang (DOI: 10.1002/JCTB.2202), published online on 28 April 2009 in Wiley InterScience (www.interscience.wiley.com), has been retracted by agreement between the authors and John Wiley & Sons, Ltd. The retraction has been agreed because a duplicate version of the article was published on 6 May 2009 (DOI: 10.1002/JCTB.2199). This occurred due to a technical error. The publishers wish to apologise for this error.
Conflict and resolution between phylogenies inferred from molecular and phenotypic data sets for hagfish, lampreys, and gnathostomes
Authors: Near Thomas J.
Published: April 2009

One of the most problematic issues in vertebrate phylogenetics is the disagreement between phenotypic and molecular inferences regarding the relationships among hagfishes, lampreys, and gnathostomes. Phenotypic characters support monophyly of lampreys and gnathostomes, whereas nearly all published analyses of molecular data sets support monophyly of hagfishes and lampreys. In this study I present results of phylogenetic analyses of combined phenotypic and molecular data sets that focus on relationships among hagfishes, lampreys, and gnathostomes. Maximum parsimony analyses of 115 phenotypic characters combined with 4,638 rRNA sites and more than 10,000 amino acids each result in monophyly of lampreys and gnathostomes, demonstrating that the addition of relatively few phenotypic characters can alter phylogenetic inferences from large molecular data sets. On the other hand, Bayesian analyses of the combined data sets support monophyly of hagfish and lampreys, indicating that model‐based analyses may be prone to data “swamping,” where the phylogenetic signal of the larger molecular data sets overwhelm the signal present in the much smaller phenotypic data set. Nodes that relate hagfish and lampreys were recovered at a low frequency in parametric bootstrapping analyses, indicating that the timing of diversification among hagfishes, lampreys, and gnathostomes has created a difficult phylogenetic problem for molecular data. The fact that addition of relatively few phenotypic characters can alter phylogenetic inferences of cyclostome monophyly obtained from molecular data sets, and the inability of simulated data sets to recover key nodes in the craniate phylogeny provide reasons to view the strong support for cyclostome monophyly inferred from molecular data sets with a measured degree of skepticism. J. Exp. Zool. (Mol. Dev. Evol.) 312B:749–761, 2009. © 2009 Wiley‐Liss, Inc.
Fin regeneration from tail segment with musculature, endoskeleton, and scales
Authors: Shao Jinhui , Qian Xiaojing , Zhang Chengxia , Xu Zenglu
Published: April 2009

It is well known that fish caudal fins can be completely regenerated after fin amputation. Although much research on fin regeneration has been carried out, there have been very few reports regarding fin regeneration after tail amputation. In this study, we used grass carp, common carp, koi carp, and zebrafish as experimental organisms. Some caudal fins could be distinctly regenerated in 2 weeks after tail amputation. After all‐trans‐retinoic acid treatment and tail amputation, zebrafish were unable to regenerate caudal fins that could be seen with the naked eye. However, after tail amputation, more than half of the zebrafish tested were able to regenerate caudal fins. Caudal fin regeneration depended on the presence of musculature and endoskeleton at the site of amputation. These caudal fins arose from segments of the endoskeleton, which contrast with currently accepted knowledge. J. Exp. Zool. (Mol. Dev. Evol.) 312B:762–769, 2009. © 2009 Wiley‐Liss, Inc.