bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electron spin resonance and quantum critical phenomena in VOx multiwall nanotubes
Authors: Demishev S. V. , Chernobrovkin A. L. , Goodilin E. A. , Glushkov V. V. , Grigorieva A. V. , Samarin N. A. , Sluchanko N. E. , Semeno A. V. , Tretyakov Yu. D. 
Published: July 2008

AbstractBasing on the high frequency (60 GHz) electron spin resonance study of the VOx multiwall nanotubes (VOx ‐NTs) carried out in the temperature range 4.2–200 K we report: (i) the first direct experimental evidence of the presence of the antiferromagnetic dimers in VOx ‐NTs and (ii) the observation of an anomalous low temperature growth of the magnetic susceptibility for quasi‐free spins, which obey the power law χ (T)∼1/T α with the exponent α ≈ 0.6 in a wide temperature range 4.2–50 K. We argue that the observed departures from the Curie–Weiss behaviour manifest the onset of the quantum critical regime and formation of the Griffiths phase as a magnetic ground state of these spin species. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adaptive charting schemes based on double sequential probability ratio tests
Authors: Li Yan , Pu Xiaolong , Tsung Fugee 
Published: July 2008

AbstractSequential probability ratio test (SPRT) control charts are shown to be able to detect most shifts in the mean or proportion substantially faster than conventional charts such as CUSUM charts. However, they are limited in applications because of the absence of the upper bound on the sample size and possibly large sample numbers during implementation. The double SPRT (2‐SPRT) control chart, which applies a 2‐SPRT at each sampling point, is proposed in this paper to solve some of the limitations of SPRT charts. Approximate performance measures of the 2‐SPRT control chart are obtained by the backward method with the Gaussian quadrature in a computer program. On the basis of two industrial examples and simulation comparisons, we conclude that the 2‐SPRT chart is competitive in that it is more sensitive and economical for small shifts and has advantages in administration because of fixed sampling points and a proper upper bound on the sample size. Copyright © 2008 John Wiley & Sons, Ltd.
The characterization of selected drugs with infrared laser desorption/tunable synchrotron vacuum ultraviolet photoionization mass spectrometry
Authors: Pan Yang , Yin Hao , Zhang Taichang , Guo Huijun , Sheng Liusi , Qi Fei 
Published: July 2008

AbstractSome selected drugs including captopril, fudosteine and racecadotril have been analyzed by infrared (IR) laser desorption/tunable synchrotron vacuum ultraviolet (VUV) photoionization mass spectrometry (PIMS). The molecular ions of captopril and racecadotril are exclusively observed without any fragments at near threshold single‐photon ionization (SPI). However, fudosteine easily forms fragments even at a photon energy near the ionization threshold, indicating the instability of its molecular ion. For these drugs, a number of fragments are yielded with the increase of photon energy. The structures of such fragments proposed by IR LD/VUV PIMS are supported by electron ionization time‐of‐flight mass spectrometry (EI‐TOFMS) results. Fragmentation pathways are discussed in detail. Copyright © 2008 John Wiley & Sons, Ltd.
Gas chromatography flow rates for determining deuterium/hydrogen ratios of natural gas by gas chromatography/high‐temperature conversion/isotope ratio mass spectrometry
Authors: Jia Wanglu , Peng Ping'an , Liu Jinzhong 
Published: July 2008

AbstractThe effects of the gas chromatography flow rate on the determination of the deuterium/hydrogen (D/H) ratios of natural gas utilising gas chromatography/high‐temperature conversion/isotope ratio mass spectrometry (GC/TC/IRMS) have been evaluated. In general, the measured δD values of methane, ethane and propane decrease with increase in column flow rate. When the column flow rate is 1 mL/min or higher, which is commonly used for the determination of D/H ratios of natural gas, the organic H in gas compounds may not be completely converted into hydrogen gas. Based on the results of experiments conducted on a GC column with an i.d. of 0.32 mm, a GC flow rate of 0.6 mL/min is proposed for determining the D/H ratios of natural gas by GC/TC/IRMS. Although this value may be dependent on the instrument conditions used in this work, we believe that correct δD values of organic compounds with a few carbon atoms are obtained only when relatively low GC flow rates are used for D/H analysis by GC/TC/IRMS. Moreover, as the presence of trace water could significantly affect the determination of D/H ratios, a newly designed inlet liner was used to remove trace water contained in some gas samples. Copyright © 2008 John Wiley & Sons, Ltd.
A laboratory comparison of two methods used to estimate the isotopic composition of soil δ13CO2 efflux at steady state
Authors: Kayler Zachary E. , Sulzman Elizabeth W. , Marshall John D. , Mix Alan , Rugh William D. , Bond Barbara J. 
Published: July 2008

AbstractThe stable isotopic composition of soil 13CO2 flux is important for monitoring soil biological and physical processes. While several methods exist to measure the isotopic composition of soil flux, we do not know how effective each method is at achieving this goal. To provide clear evidence of the accuracy of current measurement techniques we created a column filled with quartz sand through which a gas of known isotopic composition (−34.2‰) and concentration (3000 ppm) diffused for 7 h. We used a static chamber at equilibrium and a soil probe technique to test whether they could identify the isotopic signature of the known gas source. The static chamber is designed to identify the source gas isotopic composition when in equilibrium with the soil gas, and the soil probe method relies on a mixing model of samples withdrawn from three gas wells at different depths to identify the gas source. We sampled from ports installed along the side of the sand column to describe the isotopic and concentration gradient as well as to serve as a control for the soil probe. The soil probe produced similar isotopic and concentration values as the control ports, as well as Keeling intercepts. The static chamber at equilibrium did not identify the source gas but, when applied in a two end‐member mixing model, did produce a similar Keeling intercept produced from the control ports. Neither of the methods was able to identify the source gas via the Keeling plot method probably because CO2 profiles did not reach isotopic steady state. Our results showed that the static chamber at equilibrium should be used only with a Keeling plot approach and that the soil probe is able to provide estimates of uncertainty for the isotopic composition of soil gas as well as information pertinent to the soil profile. Copyright © 2008 John Wiley & Sons, Ltd.
The patch mosaic of an old‐growth warm‐temperate forest: patch‐level descriptions of 40‐year gap‐forming processes and community structures
Authors: Manabe Tohru , Shimatani Kenichiro , Kawarasaki Satoko , Aikawa Shin‐Ichi , Yamamoto Shin‐Ichi 
Published: July 2008

AbstractOld‐growth forests consist of various types of small patches that reflect their own gap‐forming process, which includes changes in environmental conditions occurring over several decades. We reconstructed the gap‐forming processes that had occurred during a 40‐year period for eight representative patches of an old‐growth evergreen broad‐leaved forest in Japan, and examined the current community structure. The selected patches were based on (1) changes in canopy heights estimated from aerial photographs taken in four different years, (2) long‐term ecological research (LTER) monitoring records, and (3) a recent field survey, so that they sufficiently covered characteristic gap‐forming processes such as a new gap, an old gap and consistently closed canopy. Height and diameter at breast height (DBH) were measured on all living trees taller than 1.3 m. In their height distributions, currently almost closed patches that were open in 1966 show a rotated sigmoid, whereas their DBH distributions are an inverse J‐shape. In contrast, patches that have been consistently under a closed canopy exhibit gentle inverse J‐shapes for both distributions. For species composition, there are no clear contrasts associated with the past gap‐forming processes except for the existence of fast‐growing deciduous species in large currently open patches. Our results suggested that the variation in several decades of gap‐forming processes played a central role in the high patch diversity and the complex patch mosaic of the forest. Diverse gap‐forming processes created micro‐environmental heterogeneity both vertically and horizontally, and contributed to the maintenance of the species‐rich, warm‐temperate old‐growth forest.
An Improved Method for Separating Cardiolipin by HPLC
Authors: Barceló‐Coblijn Gwendolyn , Murphy Eric J. 
Published: July 2008

AbstractHerein we report an improved method to separate cardiolipin (Ptd2Gro) from tissue total lipid extracts using a biphasic solvent system combined with high performance liquid chromatography. This method uses a normal phase silica column and two mobile phases: mobile phase A that was n‐hexane:2‐propanol (3:2 by vol) and mobile phase B that was n‐hexane:2‐propanol:water (56.7:37.8:5.5 by vol). The initial solvent conditions were 95% A and 5% B, with a flow rate of 1.5 mL/min. The samples were from non‐derivatized aliquots of liver, heart, or brain lipid extracts. The peak corresponding to Ptd2Gro appeared at 31 min, was well defined and did not overlap with neighboring peaks. The adjacent peak corresponded to ethanolamine glycerophospholipids and the remaining phospholipids were eluted in a single peak. The identity of the phospholipids separated by this method was verified by thin layer chromatography (TLC) and fatty acid analysis, which confirmed that the Ptd2Gro was well resolved from other phospholipids. This method is useful to separate and quantify Ptd2Gro from small tissue samples thereby avoiding the variability associated with TLC methods.
18O Labeling for a Quantitative Proteomic Analysis of Glycoproteins in Hepatocellular Carcinoma
Authors: Chaerkady Raghothama , Thuluvath Paul J. , Kim Min-Sik , Nalli Anuradha , Vivekanandan Perumal , Simmers Jessica , Torbenson Michael , Pandey Akhilesh 
Published: July 2008

AbstractIntroductionQuantitative proteomics using tandem mass spectrometry is an attractive approach for identification of potential cancer biomarkers. Fractionation of complex tissue samples into subproteomes prior to mass spectrometric analyses increases the likelihood of identifying cancer-specific proteins that might be present in low abundance. In this regard, glycosylated proteins are an interesting class of proteins that are already established as biomarkers for several cancers.Materials and MethodsIn this study, we carried out proteomic profiling of tumor and adjacent non-cancer liver tissues from hepatocellular carcinoma (HCC) patients. Glycoprotein enrichment from liver samples using lectin affinity chromatography and subsequent18O/16O labeling of peptides allowed us to obtain relative abundance levels of lectin-bound proteins. As a complementary approach, we also examined the relative expression of proteins in HCC without glycoprotein enrichment. Lectin affinity enrichment was found to be advantageous to quantitate several interesting proteins, which were not detected in the whole proteome screening approach. We identified and quantitated over 200 proteins from the lectin-based approach. Interesting among these were fetuin, cysteine-rich protein 1, serpin peptidase inhibitor, leucine-rich alpha-2-glycoprotein 1, melanoma cell adhesion molecule, and heparan sulfate proteoglycan-2. Using lectin affinity followed by PNGase F digestion coupled to18O labeling, we identified 34 glycosylation sites with consensus sequence N-X-T/S. Western blotting and immunohistochemical staining were carried out for several proteins to confirm mass spectrometry results.ConclusionThis study indicates that quantitative proteomic profiling of tumor tissue versus non-cancerous tissue is a promising approach for the identification of potential biomarkers for HCC.
NF‐κB‐dependency and consequent regulation of IL‐8 in echinomycin‐induced apoptosis of HT‐29 colon cancer cells
Authors: Park Ju Youn , Chang Jae‐Ho , Bae Keum Seok , Lee Kyoung Ho , Choi Sun Ju , Park Joo Young , Ryang Yong Suk , Kim Soo‐Ki 
Published: July 2008

AbstractThe present study was to see whether echinomycin‐induced apoptosis would be NF‐κB‐dependent and if so, whether echinomycin would activate or inhibit NF‐κB as well as resultant chemokine IL‐8 expression. In HT‐29 cells echinomycin activated NF‐κB in time‐dependent manner. EMSA in the presence of antibodies specific for p50 and p65 subunits indicated that echinomycin‐induces the translocation of p50–p65 heterodimeric subunits of NF‐κB. Levels of IκB were detected at initial echinomycin treatment and thereafter decreased, faintly seen after a 6 h treatment. In contrast p‐IκB levels were clearly detected throughout 6–24 h of echinomycin treatment, albeit initially fainted. To clarify the role of NF‐κB on IL‐8 expression in echinomycin‐mediated apoptosis of HT‐29 cells, ELISA plus RT‐PCR clearly showed that IL‐8 production is inducible by echinomycin treatment. Using a specific inhibitor, IL‐8 regulation at echinomycin treatment in HT‐29 cells occurred via both caspase‐3 and NF‐κB‐dependent signal pathway. To confirm whether two different pathways (NF‐κB and caspase) would be coupled, only NF‐κB inhibitor (PDTC) and caspase‐3 specific inhibitor (Z‐DEVD‐FMK) together significantly attenuated echinomycin‐initiated apoptosis of HT‐29 cells, pretreatment of HT‐29 cells with PDTC rarely affected echinomycin‐induced caspase‐3 activation. So echinomycin‐induced apoptosis in HT‐29 cells occurs via NF‐κB activation independent of caspase‐3 activation modulating the resultant‐linked key chemokine IL‐8 expression and echinomycin‐induced apoptosis is NF‐κB‐dependant and directly related to NF‐κB activation, consequently regulating IL‐8 expression.
Interactions between the budding yeast IQGAP homologue Iqg1p and its targets revealed by a split‐EGFP bimolecular fluorescence complementation assay
Authors: Pathmanathan Sevvel , Barnard Emma , Timson David J. 
Published: July 2008

AbstractA split‐EGFP based bimolecular fluorescence complementation (BiFC) assay has been used to detect interactions between the Saccharomyces cerevisiae cytoskeletal scaffolding protein Iqg1p and three targets: myosin essential light chain (Mlc1p), calmodulin (Cmd1p) and the small GTPase Cdc42p. The format of the BiFC assay used ensures that the proteins are expressed at wild type levels thereby avoiding artefacts due to overexpression. This is the first direct in vivo detection of these interactions; in each case, the complex is localised to discrete regions of the yeast cytoplasm. The labelling with EGFP fragments results in changes in growth kinetics, cell size and budding frequency. This is partly due to the reassembled EGFP locking the complexes into essentially permanent interactions. The consequences of this for Iqg1p interactions and BiFC assays in general are discussed.
Chronic pain and other sequelae in long‐term breast cancer survivors: Nationwide survey in Denmark
Authors: Peuckmann V. , Ekholm O. , Rasmussen N.K. , Groenvold M. , Christiansen P. , Møller S. , Eriksen J. , Sjøgren P. 
Published: July 2008

ABSTRACTObjectives: To investigate self‐reported chronic pain and other sequelae in a nationally representative sample of long‐term breast cancer survivors (BCS).Design: Age‐stratified random sample of 2,000 female BCS ≥ 5 years after primary surgery without recurrence drawn from the Danish Breast Cancer Cooperative Group register, which is representative regarding long‐term BCS in Denmark.Assessment: Self‐administered questionnaire including questions on sociodemography, chronic pain (≥6 months), health‐related quality of life (HRQOL) and other sequelae related to breast cancer. Associations with treatment were investigated. Report of chronic pain was compared to normative data.Results: The response rate was 79%. Chronic pain prevalence of 42% was significantly higher in BCS compared to general population women (SRR: 1.32; 95% CI: 1.23–1.42). Sequelae related to breast cancer were paraesthesia 47%, chronic pain 29%, arm/shoulder swelling 25%, phantom sensations 19%, and allodynia 15%. Chronic pain related to breast cancer was significantly associated with poorer HRQOL and higher medicine consumption, and, in multiple logistic regression analysis, with age (<70 years), short education, being single (divorced, widowed, separated), radiotherapy, and time since operation <10 years. Radiotherapy and younger age were significantly associated with most sequelae.Conclusion: Chronic pain was more prevalent in BCS compared to the general population. Significant predictors for sequelae related to breast cancer were radiotherapy and younger age. Future research should therefore prioritize sequelae prevention.
Prenatal exposure to a non‐steroidal anti‐inflammatory drug or saline solution impairs sciatic nerve morphology: a stereological and histological study
Authors: Canan Sinan , Aktaş Abit , Ulkay M. Basak , Colakoglu Serdar , Ragbetli Murat Cetin , Ayyildiz Mustafa , Geuna Stefano , Kaplan Suleyman 
Published: July 2008

AbstractThe toxic effect of non‐steroidal anti‐inflammatory drugs (NSAIDs) during development has been widely investigated. While it has been shown that these drugs impair central nervous development and compromise the neural activity, the effects of these substances on the development of peripheral nerves are still not clarified. In the present study, sciatic nerves withdrawn from three experimental groups of 4‐week‐old rats, prenatally exposed to either saline solution, or diclofenac sodium, and controls not exposed to any substance, were evaluated in terms of axon number, cross‐sectional area of axon and myelin sheet thickness as well as of the ultrastructure of nerve fibers. Comparisons of stereological estimations among these three groups showed that axon number and mean axon cross‐sectional area, but not average myelin sheet thickness, were significantly decreased in rats that were exposed to both diclofenac sodium and also to the saline solution, in comparison of the control group. Electron microscope analysis revealed, in both treated groups, deterioration of myelin sheaths that was more pronounced in rats that were exposed to diclofenac sodium. Altogether, these findings show that the prenatal administration of both diclofenac sodium and saline solution impairs peripheral nervous system development, thus suggesting that this potential teratogenic effect should be also taken into consideration in the clinical use of these substances in pregnant patients.
Clinical and metabolic effects of medroxyprogesterone acetate and ethinyl estradiol plus drospirenone in women with polycystic ovary syndrome
Authors: Özdemir Suna , Görkemli Hüseyin , Gezginç Kazim , Özdemir Mustafa , Kiyici Aysel 
Published: July 2008

AbstractObjectives: To investigate the effects of treatment with medroxyprogesterone acetate (MPA), 10 days per month for 6 months, on lipid and carbohydrate metabolism in women with polycystic ovary syndrome (PCOS). Methods: Sixty‐three women with PCOS were randomized to receive MPA or ethinyl estradiol plus drospirenone. Results: There were no changes in lipid or carbohydrate metabolism in the MPA group, but serum levels of luteinizing hormone (P < 0.001) and total testosterone (P < 0.003) significantly decreased, as did the free androgen index (P < 0.02) and acne (P < 0.03) and seborrhea (P < 0.04) scores. In the ethinyl estradiol plus drospirenone group lipid and hormone values significantly increased whereas acne, seborrhea, hair loss, and Ferriman‐Gallwey scores decreased. There was no statistically significant change in the total cholesterol to high‐density cholesterol ratio in either group. Conclusion: Treatment of PCOS patients with MPA provided good menstrual cycle control, beneficial changes in hormonal values associated with hyperandrogenism, and no significant changes in lipid or carbohydrate metabolism.
Human defensins and cytokines in vaginal lavage fluid of women with bacterial vaginosis
Authors: Fan S.R. , Liu X.P. , Liao Q.P. 
Published: July 2008

AbstractObjectiveTo measure the concentrations of interferon gamma (IFN‐γ), interleukin (IL)‐2, IL‐4, IL‐5, human β‐defensin 2 (HBD‐2), and human defensin 5 (HD‐5) in the vaginal lavage fluid (VLF) of healthy women and women with bacterial vaginosis (BV).MethodsVLF samples were obtained from 73 women with BV, 15 women with intermediate vaginal flora, 33 healthy women with vaginal pH greater than or equal to 4.5, and a control group of 39 healthy women with vaginal pH less than 4.5. The concentrations of IFN‐γ, IL‐2, IL‐4, IL‐5, HBD‐2, and HD‐5 were measured using enzyme‐linked immunosorbent assay kits.ResultsConcentrations of HBD‐2 and HD‐5 in the VLF of women with BV were significantly higher than in the control group (P < 0.05). IL‐4 concentration was significantly lower in the VLF of women with BV than in the control group (P < 0.05).ConclusionsHBD‐2 and HD‐5 may be involved in defending against invasion by BV‐related microorganisms and the decrease in IL‐4 concentration may increase susceptibility to BV.
A 14,300-year-long record of fire–vegetation–climate linkages at Battle Ground Lake, southwestern Washington
Authors: Walsh Megan K. , Whitlock Cathy , Bartlein Patrick J. 
Published: July 2008

AbstractHigh-resolution macroscopic charcoal analysis was used to reconstruct a 14,300-year-long fire history record from the lower Columbia River Valley in southwestern Washington, which was compared to a previous vegetation reconstruction for the site. In the late-glacial period (ca. 14,300-13,100 cal yr BP), Pinus/Picea-dominated parkland supported little to no fire activity. From the late-glacial to the early Holocene (ca. 13,100-10,800 cal yr BP), Pseudotsuga/Abies-dominated forest featured more frequent fire episodes that burned mostly woody vegetation. In the early to middle Holocene (ca. 10,800-5200 cal yr BP), Quercus-dominated savanna was associated with frequent fire episodes of low-to-moderate severity, with an increased herbaceous (i.e., grass) charcoal content. From the middle to late Holocene (ca. 5200 cal yr BP to present), forest dominated by Pseudotsuga, Thuja-type, and Tsuga heterophylla supported less frequent, but mostly large or high-severity fire episodes. Fire episodes were least frequent, but were largest or most severe, after ca. 2500 cal yr BP. The fire history at Battle Ground Lake was apparently driven by climate, directly through the length and severity of the fire season, and indirectly through climate-driven vegetation shifts, which affected available fuel biomass.