bluuebunny/crossref_metadata_2025 huggingface dataset:
Age‐dependent effect of nitric oxide on subventricular zone and olfactory bulb neural precursor proliferation
Authors: Romero‐Grimaldi Carmen , Moreno‐López Bernardo , Estrada Carmen
Published: November 2007

Nitric oxide (NO) synthase (NOS) is developmentally regulated in the embryonic brain, where NO participates in cell proliferation, survival, and differentiation. In adults, NO inhibits neurogenesis under physiological conditions. This work investigates whether the NO action is preserved all along development up to adulthood or whether its effects in adults are a new feature acquired during brain maturation. The relationship between nitrergic neurons and precursors, as well as the functional consequences of pharmacological NOS inhibition, were comparatively analyzed in the subventricular zone (SVZ) and olfactory bulb (OB) of postnatal (P7) and adult (>P60) mouse brains. The SVZ was markedly reduced between P7 and adults, and, at both ages, neurons expressing neuronal NOS (nNOS) were found in its striatal limits. In postnatal mice, these nitrergic neurons contained PSA‐NCAM, and their projections were scarce, whereas, in adults, mature nitrergic neurons, devoid of PSA‐NCAM, presented abundant neuropil. In the OB, local proliferation almost disappeared in the transition to adulthood, and periglomerular nitrergic neurons, some of which were PSA‐NCAM positive, were found in postnatal and adult mice. Administration of the NOS inhibitor L‐NAME did not affect cell proliferation in the SVZ or in the OB of postnatal mice, whereas it significantly enhanced the number of mitotic cells in both regions in adults. Thus, the NO action on SVZ neurogenesis is a phenomenon that appears after the postnatal age, which is probably due to the germinal layer size reduction, allowing exposure of the NO‐sensitive neural precursors to the NO produced in the SVZ‐striatum limits. J. Comp. Neurol. 506:339–346, 2008. © 2007 Wiley‐Liss, Inc.
A diagonal offset algorithm for the polynomial point interpolation method
Authors: Kanber B. , Bozkurt O. Y.
Published: November 2007

A diagonal offset algorithm is presented to overcome the singular moment matrix problem in the polynomial point interpolation method. The value of terms in the diagonal line of moment matrix is changed with different offsets. The effects of the offsets on the Kronecker delta function and partition of unity properties are investigated and an optimum offset range is proposed. The algorithm is validated solving some patch tests and various elasticity problems in 2‐D domain. Their results demonstrate that the proposed algorithm is very easy to implement and completely solves the singular moment matrix problem. The accuracy of the method with proposed algorithm is investigated for regular and irregular local domains. Copyright © 2007 John Wiley & Sons, Ltd.
The developmental construction of heredity
Authors: Jablonka Eva
Published: November 2007

Through his empirical and theoretical work, Gottlieb advanced a sophisticated and integrated view of development, which he saw as a probabilistic process of construction involving bidirectional interactions between structures and functions, and the phenotypic accommodation of the organism to changing environmental conditions. Gottlieb developed these ideas within a broad framework that went beyond the lifecycle of the individual. From his perspective as a developmental psychologist, he contributed to a way of thinking about evolutionary processes that stresses the importance and primacy of the modifications that occur during development. Through their long‐term effects on physiology and behavior, environmentally induced, developmental modifications may contribute to the reconstruction of an animal's developmental and ecological niches, and therefore affect the conditions in which it and its offspring are selected. Gottlieb stressed in particular the effects of prenatal and early postnatal conditions on the development of behavior, and their long‐term effects on the individual and its descendants. In this essay, I consider how the development‐oriented focus that was central to Gottlieb's perspective affects evolutionary theorizing, and, more specifically, I discuss the special status of behaviorally driven evolution. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 808–817, 2007.
Population‐based prevalence of CDKN2A and CDK4 mutations in patients with multiple primary melanomas
Authors: Helsing Per , Nymoen Dag Andre , Ariansen Sarah , Steine Solrun J. , Maehle Lovise , Aamdal Steinar , Langmark Frøydis , Loeb Mitchell , Akslen Lars A. , Molven Anders , Andresen Per Arne
Published: November 2007

The presence of multiple primary cutaneous melanomas (MPM) has been advocated as guidance to identifying melanoma families. Frequencies of CDKN2A mutations in materials of sporadic MPM cases from pigmented lesion clinics vary between 8 and 15%. Patients with MPM have therefore been regarded as good candidates for CDKN2A mutational screening. We describe a population‐based study where all persons in Norway diagnosed with MPM between 1953 and 2004 (n = 738 alive per April 2004) were invited to participate. Three‐hundred‐and‐ninety patients (52.8%) responded confidentially. Mutations in CDKN2A were found in 6.9% of the respondents. Eighty‐one MPM patients (20.8%) reported that they belonged to melanoma families, and 17 (21.0%) of these harboured a CDKN2A mutation, compared to 3.2% of the nonfamilial cases. The probability of finding a CDKN2A mutation increased when the patients had three or more melanomas, or a young age of onset of first melanoma. We identified five novel CDKN2A variants (Ala57Gly, Pro81Arg, Ala118Val, Leu130Val, and Arg131Pro) and four that previously have been reported in melanoma families (Glu27X, Met53Ile, Arg87Trp, and Ala127Pro). A large deletion (g.13623_23772del10150) encompassing exon 1α and the 5′ part of exon 2 was detected in six patients with a family history of melanoma. Three patients, belonging to the same family, had the CDK4 Arg24His mutation. The frequency of CDKN2A mutations was lower than previously reported in other studies, an observation which probably is due to the population‐based design of our study. © 2007 Wiley‐Liss, Inc.
Does use of alternative medicine delay treatment of head and neck cancer? A surveillance, epidemiology, and end results (SEER) cancer registry study
Authors: Kato Ikuko , Neale Anne Victoria
Published: November 2007

Background.

The role of complementary and alternative medicine (CAM) in cancer treatment is controversial. The aim of the study was to assess whether CAM use was associated with a delay in the initiation of conventional cancer treatment for head and neck cancer.

Methods.

CAM usage data were collected by mailed questionnaire for 149 incident head and neck cancer patients who were identified through the Metropolitan Detroit Cancer Surveillance System. Time from cancer diagnosis to the start of conventional cancer treatment was analyzed by the Kaplan–Meier method.

Results.

Overall 79% of the subjects reported use of at least 1 of the CAM items asked in the questionnaire. The time to conventional cancer treatment did not differ by prior CAM use intended to treat cancer (p =.209).

Conclusions.

The results of the present registry‐based study do not suggest that alternative therapy use in patients with head and neck cancer delays conventional cancer treatment. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Subgenotype diversity of hepatitis B virus American genotype F in Amerindians from Venezuela and the general population of Colombia
Authors: Devesa M. , Loureiro C.L. , Rivas Y. , Monsalve F. , Cardona N. , Duarte M.C. , Poblete F. , Gutierrez M.F. , Botto C. , Pujol F.H.
Published: November 2007

The objective of this study was the evaluation of the genetic diversity found in HBV circulating among Venezuelan Amerindians and the general population in Colombia. Phylogenetic analysis of the S region in 194 isolates showed that genotype F is highly predominant in Colombia and Venezuela. This might be related to the genetic background of the population. F3 is the main subgenotype which circulates in both countries. Phylogenetic analysis of 61 complete genome sequences of HBV American genotypes confirms the presence of two genotypes F and H, and 4 F subgenotypes. In Venezuela, subgenotypes F1, F2, and F3 circulate in East and West Amerindians, while only F3 was found among South Amerindians. Japreira community derived from Yucpa Amerindians around 150 years ago. However, several Japreira HBV sequences were forming a clade that can be classified as subgenotype 2b, differing from Yucpa sequences that belong mainly to subgenotype F3. The apparent absence of correlation between the phylogenetic groupings of HBV isolates with the ethnical origin in aboriginal populations might be suggesting a recent origin of HBV American subgenotypes, or a genetic drift effect. J. Med. Virol. 80:20–26, 2008. © 2007 Wiley‐Liss, Inc.
Effect of taro (Colocasia esculenta) flour addition on the functional and alveographic properties of wheat flour and dough
Authors: Njintang Nicolas Y , Mbofung Carl MF , Balaam Facho , Kitissou Pierre , Scher Joel
Published: November 2007

BACKGROUND: Taro is a plant widely produced in tropical areas for its underground corms. Taro corms are highly perishable owing to their high moisture content. In order to limit post‐harvest losses and improve the production and consumption, production and utilization of taro flour have been envisaged. In connection with this, the incorporation of taro flour into wheat‐based products has been reported to increase their keeping quality. Before consideration is given to taro flour as a substitute for wheat in bread manufacture, it is necessary to characterize the functionality of the composite flour and dough. The present study investigated the physicochemical and alveographic properties of wheat–taro composite flour.

RESULTS: Three varieties of taro flour (WCN, RIN and KWN) were incorporated into wheat flour in proportions of 10%, 20% and 30% (w/w) and the water absorption capacity (WAC), retrogradation index (RI), foam capacity (FC) and other functional properties were measured. In addition, characteristics of dough rupture pressure (P), extensibility (L), elasticity index (Ie) and strength (W) of flour made from the different composites were measured using an alveograph. The results showed that WAC significantly increased from 132% (wheat flour) to 156% (30% composite flour), while RI significantly decreased from 38% to a mean value of 22%. Principal component analysis revealed that WAC and P formed a group of variables negatively correlated with a second group made of RI, FC, W, Ie and L.

CONCLUSION: Incorporating taro flour up to a level of 10% had no significant effect on the functional and alveographic properties of the flours. This suggested that in order to guarantee the quality of bread made from wheat–taro composite the level of taro addition should not exceed 10%. Copyright © 2007 Society of Chemical Industry
Keeping quality of tomato fruit by high electrostatic field pretreatment during storage
Authors: Wang Yu , Wang Baogang , Li Lite
Published: November 2007

BACKGROUND: High electrostatic field, as a feasible and non‐chemical technique, applied to food preservation is a new area of study. The present article intensively investigated this new preservation method, together with its effects on post‐harvest physiology and quality of tomato.

RESULTS: Green mature tomatoes were exposed to negative (or positive) high electrostatic field for 2 h at 20 °C and then stored for 30 days at 13 ± 1 °C, 85–90% RH. Our results indicated that negative high electrostatic field (−2 kV cm−1) could delay the decline of firmness and the change in color, total soluble sugar and titratable acidity of tomato fruit during storage. The peak of respiration and ethylene production of tomato fruit during storage were delayed by negative high electrostatic field treatment for 6 days and 3 days, respectively. Increases of malondialdehyde content and electrical conductivity in tomato fruit were inhibited significantly by negative high electrostatic field treatment during storage (P < 0.05).

CONCLUSION: A high electrostatic field of − 2 kV cm−1 can be used to keep the qualities and extend the shelf‐life of tomato fruit. Further research should be highly recommended to understand the mechanisms improving the storability of tomato fruit by negative high electrostatic field. Copyright © 2007 Society of Chemical Industry
Dual‐band filter design of combined half and quarter wavelength SIRs for WLAN applications
Authors: Chen Pow‐Wen , Ho Hao‐Hung , Ho Min‐Hua , Lee Ching‐Her
Published: November 2007

This article presents a dual‐band bandpass filter composed of λ/2 and λ/4 stepped impedance resonators for the wireless local area network applications. The filter covers both the operating frequencies of 2.45 GHz and 5.2‐5.8 GHz. The doubly parallel‐coupling mechanism is used in the filter design to reduce the insertion losses and to gain a wider bandwidth. The cross coupling configuration and the tapped‐line I/O feed are adopted in this filter design to provide the attenuation poles for improving the signal selectivity and stopband rejection levels. Experiments were conducted to verify the circuit performance. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 13–15, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22979
Reduction of numerical dispersion by optimizing second‐order cross product derivative term in the ADI‐FDTD method
Authors: Kong Ki‐Bok , Kim Jong‐Sung , Park Seong‐Ook
Published: November 2007

We propose a new adaptive alternating‐direction implicit finite‐difference time‐domain (ADI‐FDTD) to reduce the anisotropy in the numerical phase velocities. The proposed form has two anisotropic parameters on the first order terms of the time step and one parameter on the second order term of the time step. We introduce a new approach of reducing the error of the numerical phase velocity by controlling the three parameters. The numerical stability is discussed and compared with the previous approach of reducing the numerical dispersion. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 123–127, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22991
The π‐shaped wire antenna for wideband operation
Authors: Rhee Seungyup
Published: November 2007

This article presents a new simple design for a π‐shaped wire antenna for helping achieve wideband operation. The geometry of the proposed antenna is similar to that of an inverted‐L antenna with two extra open wires at each side. The measured return loss results show that the bandwidth of the proposed antenna is about 38% referenced to 3 GHz, which is about four times as wide as that of the conventional inverted‐F antenna (∼8%). The experimental results of the constructed prototype are presented. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 156–158, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22997
A miniaturized three‐port divider/combiner
Authors: Perrier A.‐L. , Duchamp J.‐M. , Ferrari P.
Published: November 2007

We propose a new topology based on a semi‐lumped complex impedance transformer for the design of miniaturized power dividers. Our design is based on an impedance transformer in the input branch and a loop in the output branches. The input impedance transformer is constituted by a transmission line loaded with a capacitor. A prototype has been realized using hybrid technology for a 1 GHz operating frequency. The electrical length of the device is 26.4°. This leads to a miniaturized device, more than three times shorter than a typical Wilkinson power divider. This divider exhibits insertion loss lower than 0.3 dB, return loss better than 20 dB and the isolation between the two output ports above 20 dB. Moreover, the low‐pass behavior of the input impedance transformer leads to a good rejection of the third harmonic. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 72–75, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23008
Lowloss MIC/MMIC compatible microstrip to waveguide transition without a balun
Authors: Reljić Boro M.
Published: November 2007

A new MIC/MMIC compatible microstrip to waveguide transition is introduced. Its main feature is balunless design, which assumes direct feeding of waveguide exciter with microstrip line—i.e., without balun. This offer: high‐frequency, wideband, and lowloss operation, using lowcost low DK substrates, and size reduction of transition more than three times. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 107–111, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23012
Element‐free Galerkin method for transient electromagnetic field simulation
Authors: Liu Xiaofei , Wang Bing‐Zhong , Lai Shengjian
Published: November 2007

Element‐free Galerkin method (EFGM) is extended to simulate transient electromagnetic field. EFGM, which is based on moving least‐square interpolations for the test and trial functions, is a promising method that needs no element connectivity data but only a set of nodes in computational domain and boundaries and does not suffer much degradation in accuracy when nodal arrangements are very irregular. EFGM is applicable to arbitrary shapes; therefore, it can solve some problems that traditional grid‐based methods cannot solve effectively in time‐domain electromagnetic field, such as thin plate problems, narrow gap problems, antenna structure optimization, etc. The numerical examples present the validation of EFGM in transient electromagnetic field and its advantages compared with traditional numerical methods. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 134–138, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23017
A periodic porous‐nanostructured left‐handed material slab at optical frequencies
Authors: Chen P.‐Y. , Wu S.‐C.
Published: November 2007

We have proposed and theoretically investigated a left‐handed material (LHM) slab composed of porous‐nanostructed metal‐dielectric‐metal (MDM) networks for realizing negative refraction index at optical frequencies. In our design, whatever the polarization direction, provided that the electric field vector of incident EM wave is parallel to the metallic network, can “see” an equivalent LHM slab due to the symmetry and periodicity of the porous arrays. Another point needed to be highlighted is that by adjusting the periodicity of the porous arrays, a broad band of negative refraction index can be obtained. This shed the bright light on realizing negative refraction index for nanooptics and imaging applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 216–220, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23022
Miniaturized two‐pole DC‐block semicircular‐patch bandpass filter using spur‐lines
Authors: Liu Haiwen , Sun Lingling , Knoechel Reinhard H. , Schuenemann Klaus F.
Published: November 2007

A miniaturized two‐pole semicircular‐patch bandpass filter (BPF) with spur‐lines is introduced in this letter. Compared to the use of conventional feed lines, a reduction of 48% in the fundamental resonant frequency of the proposed BPF is achieved after adopting the orthogonal feed lines. Furthermore, the degenerate modes located at 5.14 GHz and 5.25 GHz can be excited by adding spur‐line structure. Besides, the gap between the semicircular‐patch resonators offers DC blocking. Finally, the simple and compact two‐pole BPF is demonstrated by measurements. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 210–213, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23027
Generalized early‐time/late‐time evolutionary programming‐based CLEAN
Authors: Choi In‐Sik , Kim Hyo‐Tae
Published: November 2007

A novel method, which is called generalized early‐time/late‐time evolutionary programming (EP)‐based CLEAN algorithm, is proposed for simultaneous extraction of the scattering centers and natural resonance frequencies of a radar target. This algorithm uses a duality between the temporal late‐time response and spectral early‐time response. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 208–210, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23032
Wide‐band compact microwave transistor amplifier methodology and the analysis of its input‐matching mechanism using negative impedance converter
Authors: Kaya Adnan
Published: November 2007

The design of broadband active‐compensated amplifier system is an important problem in microwave systems. In this letter, a wide‐band high‐gain microwave transistor amplifier (MTA) design is presented with −10 dB input reflection coefficient. To achieve its characteristics, a novel input‐matching mechanism is proposed. The recognition and comprehensive interpretation of this new input‐matching mechanism is important for future development of wide‐band MTA. In this article, broad‐band impedance matching is proposed as a method for improving the matching level of amplifier. A new compensation network consisting of negative impedance converter (NIC) circuit is employed at the input of the amplifier operating at 4.2 GHz. The results show that the compensation network can improve the return loss level from −5.9 dB to −13.01 dB, and the resonant frequency can be controlled in a wide RF band. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 192–197, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23046
Wideband patch antenna FED by printed meandering strip
Authors: Lai Hau‐Wah , Luk Kwai‐Man
Published: November 2007

A printed meandering strip (PMS) is proposed for feeding a patch antenna. It is demonstrated that the impedance matching of the antenna can be further improved by using a higher order PMS. A patch antenna fed by a first order meandering strip has an impedance bandwidth of 22% [standing wave ratio (SWR) < 1.5], cross polarization level of less than −25 dB and a gain of 9 dBi. The measured impedance bandwidths of a second order PMS and a third order PMS are 12% (SWR < 1.2) and 8% (SWR < 1.1), respectively. They have an average gain of about 9 dBi and cross polarization levels are low in level. All measurements have been confirmed by simulation. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 188–192, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23047
Electrically small antenna with frequency tuning circuit for wideband applications
Authors: Yoon Ick‐Jae , Park Se‐Hyun , Kim Youngeil , Joong Yoon Young
Published: November 2007

This study proposes the concept of frequency tuning for an electrically small antenna to be used in wideband applications in low frequencies. An electrically small antenna has too narrow bandwidth to be utilized for wideband systems. However, in such mobile TV services that the band is composed of each sub channel in VHF band, the narrow bandwidth can be appropriately utilized with wideband frequency tuning. That is, each service channel is covered by the narrow resonant band of a small sized radiator and the entire service band is satisfied by moving its frequency. To prove the idea of this study, a small helical antenna with the size of less than λ/10 is chosen as a sample and the T‐DMB service, a kind of the mobile TV services allocated to 200‐MHz band, is selected for testing. With the designed tuning circuit constituted of lumped elements and a varactor, a low impedance of the small radiator is matched to about 50 Ω and the wide bandwidth is satisfied by moving its narrow resonant frequency. The validity of the proposed antenna is also proved by the receiving measured result. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 244–247, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23049
Secondary metabolites from Paronychia argentea
Authors: Braca Alessandra , Bader Ammar , Siciliano Tiziana , De Tommasi Nunziatina
Published: November 2007

Two new oleanane saponins (1 and 2) and one new flavonol glycoside (3) together with six known flavonoids, were isolated from the aerial parts of Paronychia argentea. Their structures were elucidated by 1D and 2D NMR experiments including 1D‐TOCSY, DQF‐COSY, NOESY, HSQC, and HMBC spectroscopy, as well as ESI‐MS analysis. Copyright © 2007 John Wiley & Sons, Ltd.
High‐resolution morphological and electrical characterisation of organic bulk heterojunction solar cells by scanning probe microscopy
Authors: Douhéret O. , Swinnen A. , Bertho S. , Haeldermans I. , D'Haen J. , D'Olieslaeger M. , Vanderzande D. , Manca J. V.
Published: November 2007

State‐of‐the‐art organic bulk heterojunction (BH) solar cells, also called excitonic solar cells, are based on intimate mixtures of donor and acceptor organic materials of which the nanoscale morphology strongly influences both the photovoltaic performances and the stability of the device. In particular, the form and the size of the three‐dimensional (3D) interpenetrating network of donor/acceptor material is shown to be crucial for the electrical transport properties and the resulting photovoltaic properties. Powerful high‐resolution characterisation tools to locally map the morphology of these material systems are Scanning and Transmission Electron Microscopy (SEM/TEM), Atomic Force Microscopy (AFM) and Nuclear Magnetic Resonance (NMR). Yet, to correlate morphology with local electrical properties, significant progress has been made by the recent introduction of advanced Scanning Probe Microscopy (SPM) methods based on electrostatic force microscopy (EFM) and conductive atomic force microscopy (C‐AFM). EFM related methods measure the electrostatic interaction between the probe and the surface of the organic thin films, hence to derive the variations in the sample surface potential. C‐AFM based methods perform two‐dimensional (2D) current mapping of sample conductivity and local spectroscopy to analyse transversal charge transport mechanisms in the blends. In case the space charge limiting current (SCLC) regime is dominating the charge transport mechanisms, carrier mobility can also be determined. Finally, the sensitivity of C‐AFM to photovoltaic properties is reported. In this paper a review dealing with the different SPM methods currently used and the respective achievements performed on organic blends for BH solar cells is proposed. Copyright © 2007 John Wiley & Sons, Ltd.
Marked correlations in protein expression identified by proteomic analysis of human spermatozoa
Authors: de Mateo Sara , Martínez‐Heredia Juan , Estanyol Josep Maria , Domíguez‐Fandos David , Vidal‐Taboada José Manuel , Ballescà José Luis , Oliva Rafael
Published: November 2007

The present work was started to explore whether a correlation could be detected among proteomic expression, protamine content and DNA integrity in human sperm cells. Towards this goal, we extracted the proteins present in the sperm cells from 47 sperm samples from infertile patients and from ten semen donors, analysed each sample by 2‐D gel electrophoresis, and quantified the expression of 101 spots identified by MALDI‐TOF analysis. Additionally, the protamine content and DNA integrity were also determined. Several interesting proteins such as transcription factors, prohibitin, heat shock and proteasome proteins have been identified. We have found that the expression of an important number of proteins (58 different 2‐D spots) is correlated in independent sperm samples at high statistical significance (p<0.001 and r>0.5). Additionally, eight proteins have also been found to correlate with DNA integrity and seven with protamine content (p<0.05). To our knowledge, this is the first report describing the correlation between proteomics, DNA integrity and protamine content. It also sheds new light into the fundamental aspects of the human sperm and points to new potential proteins involved in male infertility.
Immuno‐qPCR detection of the tandem affinity purification (TAP)‐tag as a sensitive and accurate tool suitable for large‐scale protein quantification
Authors: Lind Kristina , Norbeck Joakim
Published: November 2007

The tandem affinity purification (TAP)‐tag has rapidly gained a wide popularity, mostly in studies on protein interactions, but lately also in large‐scale protein quantification studies. We have developed an immuno‐quantitative real‐time PCR (qPCR) method to achieve rapid, sensitive and accurate quantification of TAP‐tagged (and protein A‐tagged) proteins in yeast with a detection range between 107 and 1010 molecules. The immuno‐qPCR protein quantification showed an excellent correlation to the published in vivo fluorescent protein (GFP)‐based large‐scale protein quantifications, but allowed for a much higher sensitivity. The correlation with published data from the large‐scale Western blotting‐based quantification of the TAP‐tag was lower, but the sensitivity of detection was on roughly the same level. The practical use of the immuno‐qPCR approach was demonstrated by analysis of osmo‐regulated proteins, where the 2000‐fold increase in expression of Catalase (Ctt1p), from an extremely low basal expression, could be accurately quantified. All steps of the method, from cell growth, to protein extraction and determination and the immuno‐qPCR reaction itself are potentially amenable to automatization. Therefore, since the TAP‐tag and protein A are useful in most model organisms, the immuno‐qPCR method is both generic and suitable for large‐scale studies.
Tunnel coupling in asymmetric semimagnetic double quantum wells
Authors: Zaitsev S. V. , Welsch M. K. , Forchel A. , Bacher G.
Published: November 2007

The influence of the tunnel coupling on the steady‐state photoluminescence has been studied in Cd(Mg,Mn)Te‐based asymmetric double quantum wells (ADQWs) in a magnetic field up to B = 8 T. As grown structures were annealed to introduce Mn and Mg atoms from the opposite barriers inside pure CdTe quantum wells, resulting in a formation of the magnetic (MW) and nonmagnetic (NMW) wells, respectively. Radiative recombination in the ADQW with a wide barrier (9 nm) shows two bands, corresponding to excitons, localized in two decoupled QWs with a markedly different spin splitting: small splitting in the NMW due to the positive exciton Landé band g ‐factor and large splitting in the MW due to the giant Zeeman effect. Contrary, in the ADQW with a narrow barrier (3 nm) an unusual exciton splitting is observed with a negative value of the exciton g ‐factor and a strong circular polarization of the exciton bands. Simultaneously, a complete reduction of the MW emission is found, indicating strong interwell exciton relaxation. Calculations show that it is a strong electron coupling between the wells which is responsible for the observed behaviour. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure and gas transmission characteristics of microperforations in plastic films
Authors: Allan‐Wojtas P. , Forney C. F. , Moyls L. , Moreau D. L.
Published: November 2007

Bright field transmitted light microscopy (BFTLM), differential interference contrast light microscopy (DICLM), conventional scanning electron microscopy (SEM) and low‐vacuum scanning electron microscopy (LV‐SEM) were used to observe microperforations in plastic film used for modified atmosphere packaging. Characteristics of the microperforations, including size, shape and obstructions are indicators of consistency and reproducibility of the process used to produce the microperforations. In addition, the microperforations appeared differently on the upper and lower surfaces of the plastic films, including a local thickening at the site of the microperforation and size of the opening. Microperforations in the range of 30 to 100 µm in diameter exhibited a linear increase of both O2 and CO2 transmission rates with hole area, for diffusion under calm conditions. Further testing indicated that microperforations larger than 55 µm in diameter can lose their diffusion constant if convection is present. Holes with a diameter less than 55 µm should therefore be used to achieve the required oxygen transmission rates (OTR). Copyright © 2007 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Liquid chromatography/multi‐stage mass spectrometry of bisphenol A and its halogenated derivatives
Authors: Gallart‐Ayala Héctor , Moyano Encarnación , Galceran Maria T.
Published: November 2007

We report a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for analyzing bisphenol A (BPA) and its halogenated derivatives. Since only tetrachlorobisphenol A and tetrabromobisphenol A (TBBPA) are commercially available, mono‐, di‐ and trichlorobisphenol A were synthesized and purified in order to be used as analytical standards. This family of compounds was studied using electrospray ionization and an ion trap mass analyzer in order to characterize the new compounds and to propose fragmentation pathways. Multi‐stage mass spectrometry was used to confirm the genealogical relationship between the ions. Some product ions were traced from MS/MS to MS4 and the labelled compounds BPA‐d16 and TBBPA‐13C12 were used to assign some product ion structures. In general, the deprotonated molecule [MH]− loses a methyl and/or a halogen group during both MS/MS and MS3, while the neutral loss of CO was also observed in MS3 spectra. We selected the most intense and characteristic MS/MS transitions for LC/MS/MS analysis. LC separation was performed in a reversed‐phase column; methanol/water (no additives) was used as the mobile phase in gradient elution mode; and BPA‐d16 was chosen as the internal standard. Solid‐phase extraction (SPE) was used to pre‐concentrate and to clean up water samples. The SPE LC/MS/MS method allows BPA and its halogenated derivatives to be detected at a few parts‐per‐billion (ppb) in surface water. Copyright © 2007 John Wiley & Sons, Ltd.
Determination of the effect of humidity and relative speed on the coefficient of friction using response surface methodology
Authors: Abdo Jamil , Al‐Rawahi Nabeel
Published: November 2007

In order to clarify the influence of duration of rubbing, humidity, and relative speed and their cross influence on friction coefficient (CoF) an analytical model is developed based on experimental results to obtain friction function using response surface methodology (RSM). The CoF with the variation of the factor levels is investigated experimentally on a micro‐tribometer machine. The surface conditions of the mild steel disc base plate were ‘as‐turned’ and tested at different humidity conditions of 50, 65, and 80%, at relative speed of 0.5, 2.25, and 4 m/s and duration of rubbing of 0.5, 2.5, and 5 min. The humidity was controlled by passing a suitable combination of atmospheric air and water into a closed chamber. A standard RSM design called a central composite design (CCD) that is suited to fit a quadratic surface is utilized to study the CoF in dry contact. It is found that the CoF increased nonlinearly with the duration of rubbing at different levels of humidity and relative speed. The CoF is decreased almost linearly with humidity and relative speed at various levels of duration of rubbing. Copyright © 2008 John Wiley & Sons, Ltd.
Seismic performance of tubular structures with buckling restrained braces
Authors: Kim Jinkoo , Park Junhee , Shin Sung‐Woo , Min Kyung‐Won
Published: November 2007

In this study 36‐ and 72‐story framed and braced tubular structures were designed according to the current design code and their seismic performances were evaluated by nonlinear static and dynamic analysis. According to the analysis results, the tubular structures generally showed high earthquake‐resisting capability. The framed tube structure showed lowest stiffness and strength compared with the other model structures. The braced tube structures showed larger strength but lower overall ductility compared with framed tube structures. When buckling‐restrained braces were used instead of conventional braces, strength increased significantly compared with the framed tube, and ductility was enhanced compared with braced tube structures. As the load–displacement relationship estimated by static pushover analysis formed the lower bound of the dynamic analysis results, the response modification factors obtained based on the static pushover curve may safely be used for seismic design. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of Prognostic Factors Influencing Long‐term Survival After Hepatic Resection for Metastatic Colorectal Cancer
Authors: Arru Marcella , Aldrighetti Luca , Castoldi Renato , Di Palo Saverio , Orsenigo Elena , Stella Marco , Pulitanò Carlo , Gavazzi Francesca , Ferla Gianfranco , Di Carlo Valerio , Staudacher Carlo
Published: November 2007

Background

The aim of this study was to analyze the prognostic factors associated with long‐term outcome after liver resection for colorectal metastases. The retrospective analysis included 297 liver resections for colorectal metastases.

Methods

The variables considered included disease stage, differentiation grade, site and nodal metastasis of the primary tumor, number and diameter of the lesions, time from primary cancer to metastasis, preoperative carcinoembryonic antigen (CEA) level, adjuvant chemotherapy, type of resection, intraoperative ultrasonography and portal clamping use, blood loss, transfusions, complications, hospitalization, surgical margins status, and a clinical risk score (MSKCC‐CRS).

Results

The univariate analysis revealed a significant difference (p < 0.05) in overall 5‐year survival rates depending on the differentiation grade, preoperative CEA >5 and >200 ng/ml, diameter of the lesion >5 cm, time from primary tumor to metastases >12 months, MSKCC‐CRS >2. The multivariate analysis showed three independent negative prognostic factors: G3 or G4 grade, CEA >5 ng/ml, and high MSKCC‐CRS.

Conclusions

No single prognostic factor proved to be associated with a sufficiently disappointing outcome to exclude patients from liver resection. However, in the presence of some prognostic factors (G3–G4 differentiation, preoperative CEA >5 ng/ml, high MSKCC‐CRS), enrollment of patients in trials exploring new adjuvant treatments is suggested to improve the outcome after surgery.
Flipping burgers or flipping pages? Student employment and academic attainment in post-Soviet Latvia
Authors: Auers Daunis , Rostoks Toms , Smith Kenneth
Published: November 2007

Latvian higher education has undergone a dramatic transition since 1991. This study employs a survey of nearly 1000 social science students studying in 13 different institutions in Latvia to consider the impact of the increase in the number of students who are working while studying. Evidence indicates employment has a strong and significant negative impact on school performance, and the negative impact increases as weekly hours worked increase. This manifests itself through reduced class attendance and reduced time spent in independent study. Finally, we find that the probability of student employment is most significantly affected by the availability of financial aid, gender, ethnicity, and age.
Autumn-winter anomalous variations in bottom water and sediment temperatures in Lake Teletskoe
Authors: Duchkov A.D. , Kazantsev S.A.
Published: November 2007

We discuss the results of bottom temperature monitoring run in October through December 2005 in the deepwater basin of Lake Teletskoe at a lake depth of 320 m using an autonomous recorder. The obtained temperature patterns of water and sediments to a depth of ~1.4 m show sudden large changes. Bottom water temperature fluctuated between 2.9 and 4 °C, and the sediment geothermal gradient changed from –360 to +170 mK/m for the period of measurements. Water temperature became 0.6 °C warmer through November and suddenly switched to cooling after 5 December, and the drop reached 1.15 °C for the following 22 days. The change in water temperature caused the respective change in sediments, namely, gave rise to a positive geothermal gradient. Estimating the deep component of geothermal gradient (heat flow) with this climate noise requires a longer experiment of more than one year.
Formation of the superdeep South Caspian basin: subsidence driven by phase change in continental crust
Authors: Artyushkov E.V.
Published: November 2007

The large hydrocarbon basin of South Caspian is filled with sediments reaching a thickness of 20–25 km. The sediments overlie a 10–18 km thick high-velocity basement which is often interpreted as oceanic crust. This interpretation is, however, inconsistent with rapid major subsidence in Pliocene-Pleistocene time and deposition of 10 km of sediments because the subsidence of crust produced in spreading ridges normally occurs at decreasing rates. Furthermore, filling a basin upon a 10–18 km thick oceanic crust would require twice less sediments. Subsidence as in the South Caspian, of ≥20 km, can be provided by phase change of gabbro to dense eclogite in a 25–30 km thick lower crust. Eclogites which are denser than the mantle and have nearly mantle P velocities but a chemistry of continental crust may occur beneath the Moho in the South Caspian where consolidated crust totals a thickness of 40–50 km. The high subsidence rates in the Pliocene-Pleistocene may be attributed to the effect of active fluids infiltrated from the asthenosphere to catalyze the gabbro-eclogite transition. Subsidence of this kind is typical of large petroleum provinces. According to some interpretations, historic seismicity with 30–70 km focal depths in a 100 km wide zone (beneath the Apsheron-Balkhan sill and north of it) has been associated with the initiation of subduction under the Middle Caspian. The consolidated lithosphere of deep continental sedimentary basins being denser than the asthenosphere, can, in principle, subduct into the latter, while the overlying sediments can be delaminated and folded. Yet, subduction in the South Caspian basin is incompatible with the only 5–10 km shortening of sediments in the Apsheron-Balkhan sill and south of it and with the patterns of earthquake foci that show no alignment like in a Benioff zone and have mostly extension mechanisms.
A new genus and two new species of African Fruit-flies
Authors: Austen Ernest E.
Published: November 2007

Closely allied to Ceratitis, MacLeay, and agreeing therewith in thoracic chætotaxy† and, venation : differing in general facies of body, in shape of scutellum, and in that of ovipositor, the first segment of which, instead of being flattened and truncate triangular in shape, is thickened and tubular, resembling that of Urophora.
Seasonal abundance of the parasitoid complex associated with the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) in Hangzhou, China
Authors: Liu Shu-Sheng , Wang Xin-Geng , Guo Shi-Jian , He Jun-Hua , Shi Zu-Hua
Published: November 2007

An investigation of insect parasitoids of the diamondback moth, Plutella xylostella(Linnaeus), in brassica vegetable crops in the suburbs of Hangzhou was conducted during five periods from 1989 to 1997. Eight species of primary parasitoids were recorded: Trichogramma chilonis Ishii, Cotesia plutellae Kurdjumov, Microplitis sp., Oomyzus sokolowskii Kurdjumov, Diadromus collaris(Gravenhorst), Itoplectis naranyae (Ashmead), Exochus sp. and Brachymeria excarinata Gahan. Seven species of hyperparasitoids were also collected. Rates of parasitism of eggs of P. xylostella were usually very low. However, rates of parasitism of larvae and pupae were substantial and showed two peaks each year, around June–July and September–November respectively. Rates of parasitism during peaks were usually 10–60% and reached over 80% on a few occasions. Cotesia plutellae, O. sokolowskii and D. collaris were the major larval, larval-pupal and pupal parasitoids respectively. In the field, C. plutellae was active throughout the year. Oomyzus sokolowskii was active from May to October, entered a quiescent pupal stage in October–November to overwinter and did not emerge until next April–May. Diadromus collariswas recorded from April to July and October. Rates of parasitism of P. xylostellain radish and mustard fields were usually higher than those in cabbage and Chinese cabbage fields in the same locality. Negative correlations of parasitism rates between C. plutellae and O. sokolowskii indicate a competitive relationship for host larvae between these two larval parasitoids.
Advantageous attributes of larval whitefringed weevil, Naupactus leucoloma (Coleoptera: Curculionidae) for bioassaying soil fumigants, and responses to pure and plant-derived isothiocyanates
Authors: Matthiessen J.N. , Shackleton M.A.
Published: November 2007

First instars of the soil-inhabiting whitefringed weevil, Naupactus leucoloma(Boheman), are a particularly good bioassay model for assessing volatile soil fumigants and biofumigants. Eggs are readily obtained and can be stored for long periods with larvae hatched on demand and the first instar is non-feeding, surviving without food or shelter. Longevity varies with temperature, but readily accommodates the period required to conduct bioassays without appreciable mortality of untreated controls. In vitro bioassays of pure methyl isothiocyanate, the active ingredient from metham sodium soil fumigant, and the less volatile 2-phenylethyl isothiocyanate, sensitively detected differences in toxicity and effects of temperature. Bioassay of volatiles emitted from hydrolysed tissue of various isothiocyanate-producing Brassicaplants revealed widely varying toxicity effects, indicating that bioassays with N. leucoloma are a sensitive and relevant indicator of the potential of different plants for biofumigation of soil-borne pest organisms.
Impact of adult diet on demographic and population parameters of the tropical fruit flyAnastrepha serpentina(Diptera: Tephritidae)
Authors: Jácome I. , Aluja M. , Liedo P.
Published: November 2007

The effect of artificial and natural sources of adult food on the survival and reproduction of the tropical fruit fly,Anastrephaserpentina(Wiedemann) was studied. Caged adult flies were exposed during their whole lifespan to water and one of the following diets: sucrose, intact fruit, open fruit, bird faeces, sucrose plus intact fruit, sucrose plus open fruit, sucrose plus yeast hydrolysate, and sucrose plus bird faeces. All flies exposed to intact fruit or bird faeces died within the first five days of adult life without laying eggs. Females exposed to open fruit exhibited the greatest mean longevity (56.7 days). The highest net fecundity rate was recorded from individuals exposed to sucrose plus yeast hydrolysate (164 eggs per female), followed by those exposed to bird faeces plus sucrose and open fruit (38 and 26 eggs per female, respectively). Some individuals were able to lay viable eggs late in life (>105 days of age). Only populations in which adult flies had access to either sucrose plus yeast hydrolysate, open fruit, or sucrose plus bird faeces exhibited positive intrinsic rates of increase (r). Flies offered a combination of dry sucrose plus open fruit exhibited greatly reduced net fecundity levels when compared with those individuals exposed to open fruit. Even more significantly, populations of flies offered the combination of open fruit plus sucrose exhibited negative rates of increase while those exposed to open fruit alone, grew. We postulate that this reduction in egg production can be explained by a ‘junk food syndrome’.