bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction of molybdate to molybdenum blue by Enterobacter sp. strain Dr.Y13
Authors: Shukor M.Y. , Rahman M.F. , Shamaan N.A. , Syed M.A
Published: May 2009

Extensive use of metals in various industrial applications has caused substantial environmental pollution. Molybdenum‐reducing bacteria isolated from soils can be used to remove molybdenum from contaminated environments. In this work we have isolated a local bacterium with the capability to reduce soluble molybdate to the insoluble molybdenum blue. We studied several factors that would optimize molybdate reduction. Electron donor sources such as glucose, sucrose, lactose, maltose and fructose (in decreasing efficiency) supported molybdate reduction after 24 h of incubation with optimum glucose concentration for molybdate reduction at 1.5% (w/v). The optimum pH, phosphate and molybdate concentrations, and temperature for molybdate reduction were pH 6.5, 5.0, 25 to 50 mM and 37 °C, respectively. The Mo‐blue produced by cellular reduction exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium, cadmium, copper, silver and mercury caused approximately 73, 71, 81, 77 and 78% inhibition of the molybdenum‐reducing activity, respectively. All of the respiratory inhibitors tested namely rotenone, azide, cyanide and antimycin A did not show any inhibition to the molybdenum‐reducing activity suggesting components of the electron transport system are not responsible for the reducing activity. The isolate was tentatively identified as Enterobacter sp. strain Dr.Y13 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Legionella pneumophila Dps homolog is regulated by iron and involved in multiple stress tolerance
Authors: Yu Ming‐jia , Ren Jun , Zeng Yong‐lun , Zhou Shi‐ning , Lu Yong‐jun
Published: May 2009

Iron homeostasis is essential to almost all organisms. In this study, we identified the putative homolog of the iron‐storage protein‐encoding gene, dpsL, in the intracellular pathogen Legionella pneumophila and demonstrated its expression under iron‐limited conditions and its responses to multiple stresses. Quantitative real‐time PCR analysis indicated that the expression of dpsL was enhanced under iron limitation regardless of the growth phase. Compared with the wild‐type cells, the cells devoid of dpsL were heat and H2O2‐sensitive. In contrast to the dps mutants of other bacteria, the growth of the dpsL mutant in an iron‐deprived medium was delayed but finally reached the same cell density as wild‐type cells during the stationary phase of growth. The finding that the dpsL mutant is salt resistant suggested the involvement of DpsL in virulence. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phenotypic and genotypic characterizations of rhizobia isolated from root nodules of peanut (Arachis hypogaea L.) grown in Moroccan soils
Authors: El‐Akhal M. Rabie , Rincon Ana , Mourabit Nourdin El , Pueyo Jose J. , Barrijal Said
Published: May 2009

The phenotypic and genotypic characterization of sixty‐two rhizobial isolates obtained from nodules of Arachis hypogaea in north‐western Morocco was performed. Their physiological and biochemical properties revealed a great deal of diversity among them. Isolates were classified into two major groups based on the numerical analysis of their phenotypic and genotypic characteristics. Isolates in the first group were alkali‐ and salt‐sensitive, slow or extra‐slow growers; they did not use disaccharides as carbon source and varied in the use of amino acids. ARDRA analysis of the 16S rDNA region grouped them together with reference strains belonging to the genus Bradyrhizobium. In the second group, isolates were fast growers, acid‐sensitive, and alkali‐ and salt‐tolerant; they used both mono and disaccharides as carbon sources, and methionine was the only amino acid they could metabolize as a nitrogen source. ARDRA analysis grouped them with fast‐growing reference strains. Both groups exhibited a range of variability in tolerance to heavy metals. The Intergenic Spacer (IGS)‐PCR fingerprinting analysis confirmed a high genotypic diversity at the strain level. This characterization provides a basis for the selection of peanut‐nodulating rhizobia which may have applications in formulating appropriate inocula for improving peanut crop yield on Moroccan soils, including saline and acidic marginal areas. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative proteomic analysis of passaged Helicobacter pylori
Authors: Zhang Mao‐Jun , Zhao Fei , Xiao Di , Gu Yi‐Xin , Meng Fan‐Liang , He li‐Hua , Zhang Jian‐Zhong
Published: May 2009

In order to identify the proteins associated with Helicobacter pylori colonization in mice, we used 2‐dimensional gel electrophoresis (2‐DE) to analyze the membrane‐ and soluble‐cellular proteins extracted from H. pylori strain 26695 and the mouse‐passaged homolog 88‐3887. We defined 2‐ and 3‐fold changes in protein expression as the threshold values for differential expression in the membrane‐protein and whole‐cell‐protein fractions, respectively. The differentially expressed proteins were identified by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF/TOF). A total of 29 proteins, including 16 membrane‐ or membrane‐associated proteins (13 upregulated, 3 downregulated) and 13 cellular proteins (10 upregulated, 3 downregulated) were differentially expressed between the strains 26695 and 88‐3887. Among the upregulated proteins, 10 proteins had been previously shown to be associated with the mouse colonization, and 13 upregulated proteins were shown to be associated with the adaptation of H. pylori in murine hosts for the first time in this study. The identified proteins were classified as proteins related to metabolism, stress response, virulence, or adhesion. The data presented in this report indicated that there were subsets of upregulated proteins in mouse‐adapted H. pylori. In particular, the adhesins, virulence factors, and stress‐response proteins are likely to contribute to colonization in mice. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Annual temperature history in Southwest Tibet during the last 400 years recorded by tree rings
Authors: Yang Bao , Kang Xingcheng , Liu Jingjing , Bräuning Achim , Qin Chun
Published: May 2009

We present a tree ring‐width record from the southern Tibetan Plateau (TP) which spans from 1612–1998 AD (387 years). The series was developed from Tibetan juniper (Juniperus tibetica Kom) growing at sites near the western distribution limit of the species. Two versions of the chronology, a traditionally standardized chronology (TSC) and a regional curve standardization (RCS)chronology were developed. Linear regression models between ring width and mean annual temperature account for 41% (TSC) and 43% (RCS) of the annual (July–June) temperature variance for the period 1957–1998. According to the TSC reconstruction, warm periods occurred during the 1620s, 1650–1675, 1720s, 1740–1790, 1810s, 1850s–1890s, 1935–1950, and 1957–1964 and since 1980. Cold conditions prevailed during the 1630s–1640s, 1680s–1710s, 1730s, 1820–1840s, 1900s–1920s and the 1970s. Within the last 400 years, the late‐20th century warming is distinctive but still within the range of natural climatic variability of this region. Comparison of our TSC reconstruction with proxy temperature records from other parts of the TP shows that the cold conditions during the 1730s, 1900s–1920s, and 1970s, and the warm periods during the 1770–1800, 1850s–1890s, 1935–1950, and 1957–1964 and since 1980 were synchronously occurring broad‐scale climate anomalies on the whole TP. Differences between the reconstructions are found during the 17th century and around 1760, which were probably caused by local differences in temperature change and different sensitivity in seasonality. The RCS series portrays low‐frequency variations such as warm periods during 1620–1640, 1650–1690, 1715–1790, and 1845–1875, and cold conditions during 1640–1650, 1690–1715, and 1875–1995. These long‐term trends need to be verified by developing other proxy records that target to capture low‐frequency signals in the future. Copyright © 2009 Royal Meteorological Society
Posttyphoon prevalence of posttraumatic stress disorder, major depressive disorder, panic disorder, and generalized anxiety disorder in a Vietnamese sample
Authors: Amstadter Ananda B. , Acierno Ron , Richardson Lisa K. , Kilpatrick Dean G. , Gros Daniel F. , Gaboury Mario T. , Tran Trinh Luong , Trung Lam Tu , Tam Nguyen Thanh , Tuan Tran , Buoi La Thi , Ha Tran Thu , Thach Tran Duc , Galea Sandro
Published: May 2009

In 2006, typhoon Xangsane disrupted a multiagency health needs study of 4,982 individuals in Vietnam. Following this disaster, 798 of the original participants were reinterviewed to determine prevalence and risk factors associated with posttraumatic stress disorder (PTSD), major depressive disorder (MDD), panic disorder (PD), and generalized anxiety disorder (GAD). Posttyphoon prevalences were PTSD 2.6%, MDD 5.9%, PD 9.3%, and GAD 2.2%. Of those meeting criteria for a disorder, 70% reported only one disorder, 15% had two, 14% had three, and 1% met criteria for all four disorders. Risk factors for posttyphoon psychopathology differed among disorders, but generally were related to high typhoon exposure, prior trauma exposure, and in contrast to Western populations, higher age, but not gender.
Stability of global and exponential attractors for a three‐dimensional conserved phase‐field system with memory
Authors: Mola Gianluca
Published: May 2009

We consider a conserved phase‐field system on a tri‐dimensional bounded domain. The heat conduction is characterized by memory effects depending on the past history of the (relative) temperature ϑ, which is represented through a convolution integral whose relaxation kernelkis a summable and decreasing function. Therefore, the system consists of a linear integrodifferential equation for ϑ, which is coupled with a viscous Cahn–Hilliard type equation governing the order parameter χ. The latter equation contains a nonmonotone nonlinearityϕand the viscosity effects are taken into account by a term −αΔ∂tχ, for some α⩾0. Rescaling the kernelkwith a relaxation time ε>0, we formulate a Cauchy–Neumann problem depending on ε and α. Assuming a suitable decay ofk, we prove the existence of a family of exponential attractors {ℰα,ε} for our problem, whose basin of attraction can be extended to the whole phase–space in the viscous case (i.e. when α>0). Moreover, we prove that the symmetric Hausdorff distance of ℰα,εfrom a proper lifting of ℰα,0tends to 0 in an explicitly controlled way, for any fixed α⩾0. In addition, the upper semicontinuity of the family of global attractors {𝒜α,ε} as ε→0 is achieved for any fixed α>0. Copyright © 2009 John Wiley & Sons, Ltd.
Characterization of response to radiation mediated gene therapy by means of multimodality imaging
Authors: Haney Chad R. , Parasca Adrian D. , Fan Xiaobing , Bell Rebecca M. , Zamora Marta A. , Karczmar Gregory S. , Mauceri Helena J. , Halpern Howard J. , Weichselbaum Ralph R. , Pelizzari Charles A.
Published: May 2009

Imaging techniques are under development to facilitate early analysis of spatial patterns of tumor response to combined radiation and antivascular gene therapy. A genetically modified, replication defective adenoviral vector (Ad.EGR‐TNFα), injected intratumorally, mediates infected cells to express tumor necrosis factor alpha (TNFα), which is increased after exposure to radiation. The goal of this study was to characterize an image based “signature” for response to this combined radiation and gene therapy in mice with human prostate xenografts. This study is part of an imaged guided therapy project where such a signature would be useful in guiding subsequent treatments. Changes in the tumor micro‐environment were assessed using MRI registered with electron paramagnetic resonance imaging which provides images of tissue oxygenation. Dynamic contrast‐enhanced MRI was used to assess tissue perfusion. When compared with null vector (control) treatment, the ratio of contrast agent (Gd‐DTPA‐BMA) washout rate to uptake rate was lower (P = 0.001) after treatment, suggesting a more balanced perfusion. Concomitantly, oxygenation significantly increased in the treated animals and decreased or did not change in the control animals (P < 0.025). This is the first report of minimally invasive, quantitative, absolute oxygen measurements correlated with tissue perfusion in vivo. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Motion artifact correction in free‐breathing abdominal MRI using overlapping partial samples to recover image deformations
Authors: White M. J. , Hawkes D. J. , Melbourne A. , Collins D. J. , Coolens C. , Hawkins M. , Leach M. O. , Atkinson D.
Published: May 2009

This article presents a method to reconstruct liver MRI data acquired continuously during free breathing, without any external sensor or navigator measurements. When the deformations associated with k‐space data are known, generalized matrix inversion reconstruction has been shown to be effective in reducing the ghosting and blurring artifacts of motion. This article describes a novel method to obtain these nonrigid deformations. A breathing model is built from a fast dynamic series: low spatial resolution images are registered and their deformations parameterized by overall superior–inferior displacement. The correct deformation for each subset of the subsequent imaging data is then found by comparing a few lines of k‐space with the equivalent lines from a deformed reference image while varying the deformation over the model parameter. This procedure is known as image deformation recovery using overlapping partial samples (iDROPS). Simulations using 10 rapid dynamic studies from volunteers showed the average error in iDROPS‐derived deformations within the liver to be 1.43 mm. A further four volunteers were imaged at higher spatial resolution. The complete reconstruction process using data from throughout several breathing cycles was shown to reduce blurring and ghosting in the liver. Retrospective respiratory gating was also demonstrated using the iDROPS parameterization. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Antibiotics taken for other illnesses and spontaneous clearance of Helicobacter pylori infection in children
Authors: Broussard Cheryl S , Goodman Karen J , Phillips Carl V , Smith Mary Ann , Fischbach Lori A , Day R Sue , Aragaki Corinne C
Published: May 2009

Purpose

Factors that determine persistence of untreated Helicobacter pylori (H. pylori) infection in childhood are not well understood. We estimated risk differences for the effect of incidental antibiotic exposure on the probability of a detected clearance at the next test after an initial detected H. pylori infection.

Methods

The Pasitos Cohort Study (1998–2005) investigated predictors of H. pylori infection in children from El Paso, Texas, and Juarez, Mexico. Children were screened for infection at 6‐month target intervals from 6 to 84 months of age, using the 13C‐urea breath test corrected for body‐size‐dependent variation in CO2 production. Exposure was defined as courses of any systemic antibiotic (systemic) or those with anti‐H. pylori action (HP‐effective) reported for the interval between initial detected infection and next test. Binomial regression models included country of residence, mother's education, adequacy of prenatal care, age at infection, and interval between tests.

Results

Of 205 children with a test result and antibiotic data following a detected infection, the number of children who took ≥1 course in the interval between tests was 74 for systemic and 33 for HP‐effective. The proportion testing negative at the next test was 66% for 0 courses, 72% for ≥1 systemic course, and 79% for ≥1 HP‐effective course. Adjusted risk differences (95%CI) for apparent clearance, comparing ≥1 to 0 courses were 10% (1–20%) for systemic and 11% (0–21%) for HP‐effective.

Conclusions

Incidental antibiotic exposure appears to influence the duration of childhood H. pylori infection but seems to explain only a small portion of spontaneous clearance. Copyright © 2009 John Wiley & Sons, Ltd.
Dimensional stability of single‐site ethylene copolymers in rotational molding
Authors: Bellehumeur C.T. , Medina A. , Xu H.
Published: May 2009

The dimensional stability of ethylene copolymers in rotational molding was studied by comparing the warpage observed for a series of conventional and single‐site catalyzed ethylene copolymers. Bench‐scale molding trials were carried out under controlled molding conditions. The rapid cooling of the mold using a water spray resulted in greater warpage. Under such conditions, molded parts made using the single‐site resins showed less warpage compared to the Ziegler‐catalyzed copolymers with otherwise comparable densities. The Ziegler‐catalyzed copolymers were characterized by a faster crystallization rate, and were shown to generate larger crystallinity gradients through the part thickness during the cooling process. Second to temperature gradients, crystallinity gradients are a leading cause for the development of residual stresses and causing warpage. Differences in the crystallization rates between single‐site and Ziegler‐catalyzed copolymers are discussed based on their intermolecular comonomer distributions. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Comparison of orbital and linear vibration welding of thermoplastics
Authors: Grewell David A. , Benatar Avraham
Published: May 2009

This work was conducted to determine if there were any benefits with orbital vibration welding compared to linear vibration welding. The experiments were conducted using standard full‐factorial designs with each process and each material. Four materials, polypropylene/polyethylene copolymer (PP/PE), polycarbonate (PC), acrylonitrile‐butadiene‐styrene (ABS) and Nylon (PA), were studied with each process. The equipment used was a modified Branson VW‐4 with an orbital head that had isolated magnets. The same machine was used to weld with both linear and orbital motions. This was achieved by modifying the controlling parameters of the drive. It was found that compared to linear vibration welding, orbital welding had a reduction of cycle time by 36% and 50% in Phase I and Phase III, respectively. It was also found that orbital welding dissipated 56% and 100% more power than linear vibration welding in Phase I and Phase III, respectively. In addition, it was seen that orbital welding was able to universally join unsupported walls with higher strengths and better consistency compared to linear welding. Other benefits included: a difference in the appearance of weld flash and small increase in weld strength. Some of the limitations of orbital welding that were identified included the effects of disengagement and residual stresses. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
An innovative method of die design and evaluation of flow balance for thermoplastics extrusion profiles
Authors: Zolfaghari Abbas , Behravesh Amir Hossein , Shakouri Ehsan , Soury Ehsan
Published: May 2009

In this article, a computational and experimental method for flow balancing of a U‐shaped die profile with nonuniform thicknesses is presented. The approach was to implement a flow restricting mechanism along the melt flow path. A parametric study based on the restrictor dimensions was carried out to attain a preliminary optimal design. Simulations were performed using Fluent software to analyze the flow velocity at the die exit. Experimental study was then carried out at various restrictor positions for the purpose of attaining a desirable flow balance. The velocity at various segments of the die exit was measured utilizing an innovative procedure by implementing the “separating blades.” Experimental findings were compared with those of simulations which showed an acceptable agreement. The results suggest that a flexible die can be designed to achieve a flow balance under various processing conditions. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Personality traits of Russians from the observer's perspective
Authors: Allik Jüri , Realo Anu , Mõttus René , Pullmann Helle , Trifonova Anastasia , McCrae Robert R. ,   and 56 Members of the Russian Character and Personality Survey
Published: May 2009

Data were collected by the members of the Russian character and personality survey from 39 samples in 33 administrative areas of the Russian Federation. Respondents (N = 7065) identified an ethnically Russian adult or college‐aged man or woman whom they knew well and rated the target using the Russian observer rating version of the Revised NEO Personality Inventory, which measures neuroticism, extraversion, openness to experience, agreeableness and conscientiousness. Factor analyses within samples showed that the factor structure of an international sample combining data from 50 different cultures was well replicated in all 39 Russian samples. Sex differences replicated the known pattern in all samples, demonstrating that women scored higher than men on most of the neuroticism, openness, agreeableness and conscientiousness facet scales. Cross‐sectional analyses demonstrated consistent age differences for four factors: Older individuals compared to younger ones were less extraverted and open but more agreeable and conscientious. The mean levels of traits were similar in all 39 samples. Although in general personality traits in Russians closely followed the universal pattern, some reliable culture‐specific effects were also found that future studies can help interpret. Copyright © 2009 John Wiley & Sons, Ltd.
Ground temperatures in permafrost south of treeline, Mackenzie Delta, Northwest Territories
Authors: Kanigan J. C. N. , Burn C. R. , Kokelj S. V.
Published: May 2009

Surface conditions and ground temperatures from 50‐cm to 20‐m depth were measured at 26 forested sites in the Mackenzie Delta, to determine if differences in forest structure and organic cover between four common white spruce forest community types were associated with variations in ground temperature. The mean annual temperature at 1‐m depth was lowest (−4.4°C) in the closed/spruce‐feathermoss (CSF) community associated with a thick canopy and thin snow cover, and highest in the recent permafrost of the spruce/alder‐bearberry (SAB) community (−1.0°C) with an open canopy and deep snow. The open‐canopy spruce/crowberry‐lichen (SCL) forest, with a thick surface organic cover and deep snow, had a higher mean annual temperature at 1‐m depth (−2.1°C) than the CSF forest, indicating the importance of canopy cover for snow accumulation and ground heat loss in winter. Seasonal and inter‐annual variation of 4‐m ground temperatures was greatest beneath the CSF community, highlighting the importance of greater winter cooling due to a thin snow cover and a lower unfrozen water content. Temperatures at 20‐m depth ranged from −0.6°C to −1.5°C in SAB forests, and were significantly lower in CSF, open/spruce‐feathermoss and SCL communities (−1.6°C to −2.9°C). Variation in near‐surface temperatures between spruce forest types diminishes with depth due to the thermal influence of water bodies. There was no significant variation of ground temperatures at 20‐m depth within spruce forest communities in different parts of the delta. Copyright © 2009 John Wiley & Sons, Ltd. and Her Majesty the Queen in right of Canada.
Stratigraphy and palaeoenvironments of Richards Island and the eastern Beaufort Continental Shelf during the last glacial‐interglacial cycle
Authors: Murton Julian B.
Published: May 2009

The Pleistocene lithostratigraphy exposed on northern Richards Island comprises seven units that correlate with the offshore seismostratigraphy of the eastern Beaufort Continental Shelf. Land‐sea correlations, cryostratigraphic observations and proxy indicators of environmental change provide a record of palaeoenvironmental history that commences before the last glacial‐interglacial cycle. After the high sea‐level stand of the Last (Sangamonian) Interglaciation, marine regression exposed a large area of the eastern Beaufort Shelf to cold subaerial conditions and permafrost aggradation. Northward progradation of a braided river system was abruptly replaced by aeolian activity, probably as a result of diversion of the palaeo‐Porcupine River by the advancing Laurentide Ice Sheet during the Late Wisconsinan. Glaciation of Richards Island by the Mackenzie palaeo‐ice stream was brief (sometime between ∼22 000 and 16 000 cal. yr BP), and deglaciation had certainly commenced by 14 300 cal. yr BP and perhaps by ∼16 000 cal. yr BP or earlier. Major fluvial erosion during the Last Glacial‐Interglacial Transition incised cross‐shelf valleys and formed a regional erosion surface. The Holocene marine transgression trimmed some of the erosion surface and offshore, covered it with marine deposits. Copyright © 2009 John Wiley & Sons, Ltd.
Temporal expression profiling of the effects of secreted factors from prostate stromal cells on embryonal carcinoma stem cells
Authors: Pascal Laura E. , Vêncio Ricardo Z.N. , Goo Young Ah , Page Laura S. , Shadle Christina P. , Liu Alvin Y.
Published: May 2009

BACKGROUND

There is a growing body of evidence indicating that epigenetic influences originating from stromal cells in the immediate microenvironment may play a role in carcinogenesis. Determining the molecular mechanisms involved in stromal–stem cell interaction could provide critical insight into prostate development and disease progression, particularly with regard to their relationship to and influence on the putative cancer stem cell.

METHODS

Prostate and bladder stromal cells prepared from tissue specimens were co‐cultured with the pluripotent embryonal carcinoma cell line NCCIT. Transcriptome analysis was used to characterize NCCIT cell response to prostate or bladder signaling.

RESULTS

A systems approach demonstrated that prostate stromal cells were capable of inducing gene expression changes in NCCIT through secreted factors. Induction led to a loss of embryonic stem cell markers, with concurrent up‐regulation of many genes characteristic of stromal mesenchyme cells as well as some of epithelial and cancer stem cells. Bladder stromal signaling produced gene expression changes different from those of prostate signaling.

CONCLUSIONS

This study indicates that paracrine stromal cell signaling can affect cancer stem cell response in an organ‐specific manner and may provide insight for future development of treatment strategies such as differentiation therapy. Prostate 69:1353–1365, 2009. © 2009 Wiley‐Liss, Inc.
Tuning the orthorhombic–rhombohedral phase transition temperature in sodium potassium niobate by incorporating barium zirconate
Authors: Wang Ruiping , Bando Hiroshi , Katsumata Tetsuhiro , Inaguma Yoshiyuki , Taniguchi Hiroki , Itoh Mitsuru
Published: May 2009

We report that the orthorhombic–rhombohedral phase transition temperature in sodium potassium niobate could be tuned from lower to higher than room temperature by incorporating barium zirconate into it. It is revealed that when barium zirconate is between 8 mol% and 15 mol%, the solid solution exhibits rhombohedral symmetry at room temperature. Rietveld analysis shows that the space group of the rhombohedral phase is R3m. It is suggested that a relatively larger B‐cation favors the low‐temperature phase which is a common phenomenon for perovskite ferroelectrics. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Glabridin inhibits lipopolysaccharide‐induced activation of a microglial cell line, BV‐2, by blocking NF‐κB and AP‐1
Authors: Park Sun Hong , Kang Jong Soon , Yoon Yeo Dae , Lee Kiho , Kim Kang‐Jeon , Lee Ki Hoon , Lee Chang Woo , Moon Eun‐Yi , Han Sang‐Bae , Kim Bong Hee , Kim Hwan Mook , Park Song‐Kyu
Published: May 2009

Glabridin, a flavonoid present in licorice root, is known to have antiinflammatory and cardiovascular protective activities. The present study reports an inhibitory effect of glabridin on microglial activation. Glabridin dose‐dependently attenuated lipopolysaccharide (LPS)‐induced production of inflammatory mediators, including nitric oxide, tumor necrosis factor‐α and interleukin‐1β, in BV‐2 cells, a murine microglia cell line. Moreover, mRNA expression of these inflammatory mediators was also suppressed by glabridin in LPS‐stimulated BV‐2 cells. Further study demonstrated that glabridin inhibited LPS‐induced DNA binding activity of NF‐κB and AP‐1 in BV‐2 cells. Collectively, the results presented in this report demonstrate that glabridin inhibits the production of inflammatory mediators in BV‐2 cells and this is mediated, at least in part, by blocking NF‐κB and AP‐1 activation. The results suggest that glabridin might be a potential therapeutic agent for the treatment of neuroinflammatory and neurodegenerative diseases. Copyright © 2009 John Wiley & Sons, Ltd.
Orbital‐dependent magnetic properties of molecular cluster containing high‐spin Co(II) ions
Authors: Wang Fan , Zhao Fei , Wang Bing‐Wu , Wang Ming‐Wei , Zhang Yuan‐Zhu , Wang Wei , Gao Song , Chen Zhi‐Da
Published: May 2009

To shed light on magnetic properties of the magnetic exchange molecular cluster containing the constituent metal ion with unquenched orbital angular momentum, as representative examples two octahedrally coordinated high‐spin Co(II)‐cluster complexes were synthesized and characterized: complex (1) [Co3(Hbzp)6][ClO4]2· 2CH3OH·H2O (bzp = 2‐benzoylpyridine) with a linear core Co(III)‐Co(II)‐Co(III) and complex (2) [Co4L(N3)4(CH3CN)4](ClO4)4·2H2O (L = Macrocyclic schiff base of tetra‐2,6‐pyridinedicarboxaldehyde‐tetra‐ethane‐1,2‐diamine) comprised by two nearly independent Co(II)‐dimers. Following Lines' isotropic exchange approximation the magnetic interaction effective Hamiltonian was introduced, which includes the exchange interactions, the spin‐orbit coupling, the low‐symmetry crystal field, and the intercluster exchange interaction. On the basis of the irreducible tensor operator approach to solve Hamiltonian we have coded the software, BJMAG package, and performed the best‐fit procedure for experimentally temperature variable magnetic susceptibilities for the complexes (1) and (2). The best‐fit parameters were obtained as follows: λ = −126 cm−1, Δ = 432 cm−1, κ = 0.96, mJ′ = 2.7 cm−1 for the complex (1) and λ = −165 cm−1, Δ = 960 cm−1, κ = 0.95, J′ = 9 cm−1, mJ′ = −0.1 cm−1 for the complex (2). To further elucidate the individual role of each interaction in the employed model, the effects of the key factors governing the magnetic properties on temperature variable magnetic susceptibilities were examined in detail. The significance of the intercluster exchange interactions at low temperatures was briefly discussed and a self‐consistent molecular field to calculate the thermally average spin of the nearest neighbor in the intercluster interaction was proposed. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
The biophysical basis of Benveniste experiments: Entropy, structure, and information in water
Authors: Widom Allan , Srivastava Yogendra , Valenzi Vincenzo
Published: May 2009

Benveniste had observed that highly dilute (and even in the absence of physical molecules) biological agents still triggered relevant biological systems. Some of these experiments were reproduced in three other laboratories who cosigned the article, (Davenas et al., Nature 1988, 333, 816). Further works, [(Medical Hypotheses 2000, 54, 33), (Rivista di Biologia/Biology Forum 97, 2004, 169)], showed that molecular activity in more than 50 biochemical systems and even in bacteria could be induced by electromagnetic signals transferred through water solutes. The sources of the electromagnetic signals were recordings of specific biological activities. These results suggest that electromagnetic transmission of biochemical information can be stored in the electric dipole moments of water in close analogy to the manner in which magnetic moments store information on a computer disk. The electromagnetic transmission would enable in vivo transmissions of the specific molecular information between two functional biomolecules. In the present work, the physical nature of such biological information storage and retrieval in ordered quantum electromagnetic domains of water will be discussed. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Energetics of 1,n‐didehydro‐polyene diradicals and performance of reduced multireference coupled‐cluster method
Authors: Li Xiangzhu , Paldus Josef
Published: May 2009

The reduced multireference coupled‐cluster method with singles and doubles (RMR CCSD) and its RMR CCSD(T) version are employed to study the energetics of 1,n‐didehydro‐polyenes. The RMR CCSD method accounts for quasi‐degeneracy by exploiting a multireference (MR) CISD wave function as an external source of the most important (primary) triples and quadruples while the subsequent perturbative correction for the secondary triples leads to RMR CCSD(T). The resulting energies are compared with those yielded by the standard single‐reference (SR) CCSD and CCSD(T) approaches. We first determine the optimal geometry for each species considered. Using the CC methods just mentioned we then compute the energy of the lowest‐lying singlet and triplet states, the implied singlet‐triplet splitting, and determine the spin multiplicity of the ground state. We point out the relationship between the degree of the diradical character, the extent of quasi‐degeneracy or the MR nature of the state considered, the distance separating the radical centers and, finally, the size of the largest doubly excited cluster amplitude in the CC wave functions. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Unusual low‐intensity regime in laser‐induced molecular photodissociation
Authors: Lefebvre R. , Atabek O.
Published: May 2009

Previous investigations of laser‐induced photodissociation of a diatomic molecule (Atabek et al., Phys Rev A 2006, 74, 063412 and Atabek and Lefebvre, Phys Rev A 2008, 78, 043419) have shown that some of the Floquet eigenstates have the property that at some critical intensities their width is vanishing. These intensities are wavelength dependent. We exploit further this property by showing that by a proper choice of the wavelength, the critical intensity for a Floquet state originating from a given field‐free vibrational state can be made vanishingly small. In such a case, the rate increases with intensity in an abnormally slow way. The wavelengths, which are required to reach this regime, can be derived accurately from the semiclassical criterion to obtain a zero‐width resonance. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Relativistic perturbation theory calculation of the hyperfine structure parameters for some heavy‐element isotopes
Authors: Khetselius O. Yu
Published: May 2009

The energies and hyperfine structure constants for some Li‐like multicharged ions and atoms of 133Cs and 181Hg are calculated within the quantum electrodynamics (QED) perturbation theory formalism with correct taking into account the correlation, relativistic, nuclear, and radiative corrections. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Laparoscopic robot‐assisted completion cholecystectomy: a report of three cases
Authors: Kohn Geoffrey P. , Martinie John B.
Published: May 2009

Background

Gangrenous cholecystitis remains a serious, life‐threatening, surgical emergency. Surgeons are occasionally forced to perform a subtotal cholecystectomy and forego formal dissection of the cystic duct and artery, in an attempt to avoid iatrogenic injury to the common bile duct. Not infrequently, a patient may develop a persistent biliary fistula or symptomatic gall bladder remnant, which may ultimately require operative intervention.

Methods

Three patients were referred to the University of North Carolina Hospitals for evaluation and treatment. All patients initially presented with gangrenous cholecystitis and had undergone open cholecystectomies and placement of surgical drains at outside medical facilities. All three patients had subsequently developed persistent biliary leaks or had significant gall bladder remnants. Due to the anticipated difficulty and complexity of performing a laparoscopic completion cholecystectomy in this setting, the DaVinci® robot (Intuitive Surgical, Sunnyvale, CA, USA) was utilized for these three consecutive patients. Dissection was performed using two robotic instrument arms, as well as assistant ports for suction/irrigation devices, clips and endostaplers.

Results

All three patients were found to have significant gall bladder and cystic duct remnants, some with sizeable retained stones in the infundibulum. All procedures were completed laparoscopically with robotic assistance, with no complications. At follow‐up, all patients were without biliary leaks or symptoms.

Conclusion

Laparoscopic robot‐assisted completion cholecystectomy is a feasible option in the setting of a reoperative, hostile abdomen following gangrenous cholecystitis. Copyright © 2009 John Wiley & Sons, Ltd.
A reliable cooperative and distributed management for wireless industrial monitoring and control
Authors: Manfredi S.
Published: May 2009

This paper is concerned with the analysis, design and validation of a reliable management strategy for industrial monitoring and control over wireless sensor network (WSN). First, we investigate the interactions between contention resolution and congestion control mechanisms in Wireless Industrial Sensor Network (briefly WISN). An extensive set of simulations are performed in order to quantify the impacts of several network parameters (i.e. buffer, sensors reporting rate) on the overall network performance (i.e. reliability, packet losses). This calls for cross‐layer mechanisms for efficient data delivery over WISN. Second, a reliable sink resource allocation strategy based on log‐utility fairness criteria is proposed. It is shown that the resource sink manager can plan strategies to better allocate the available resource among competing sensors. Finally, the analysis, design and validation of a reliable sinks cooperative control for WISN are introduced. A sufficient condition for wireless network stability in presence of multiple sinks and heterogeneous sensors with different time delays is given and it is used for network parameters design. The stability condition and the resulting cooperative control performance in terms of fairness, link utilization, packet losses, reliability and latency are validated by Matlab/Simulink‐based simulator TrueTime, which facilitates co‐simulation of controller task execution in real‐time kernels and in the wireless network environment. Copyright © 2009 John Wiley & Sons, Ltd.
Coping with participant heterogeneity in dichotomous responses
Authors: Meilijson Isaac , Meilijson Sara
Published: May 2009

Participant heterogeneity induces spurious dependence that may obscure dependence patterns displayed by a covariance matrix. A parsimonious method is proposed for the reduction of this confounding effect. The method is applied to dichotomous behavioral response data of participants diagnosed with schizophrenia, as assessed by the Pragmatic Protocol (J. Speech Hear. Disord. 1987; 52:105–119). Copyright © 2009 John Wiley & Sons, Ltd.
Measurement in clinical trials: A neglected issue for statisticians?
Authors: Senn Stephen , Julious Steven
Published: May 2009

Biostatisticians have frequently uncritically accepted the measurements provided by their medical colleagues engaged in clinical research. Such measures often involve considerable loss of information. Particularly, unfortunate is the widespread use of the so‐called ‘responder analysis’, which may involve not only a loss of information through dichotomization, but also extravagant and unjustified causal inference regarding individual treatment effects at the patient level, and, increasingly, the use of the so‐called number needed to treat scale of measurement. Other problems involve inefficient use of baseline measurements, the use of covariates measured after the start of treatment, the interpretation of titrations and composite response measures. Many of these bad practices are becoming enshrined in the regulatory guidance to the pharmaceutical industry. We consider the losses involved in inappropriate measures and suggest that statisticians should pay more attention to this aspect of their work. Copyright © 2009 John Wiley & Sons, Ltd.
Power and sample size calculations for current status survival analysis
Authors: Williamson John M. , Lin Hung‐Mo , Kim Hae‐Young
Published: May 2009

Although sample size calculations have become an important element in the design of research projects, such methods for studies involving current status data are scarce. Here, we propose a method for calculating power and sample size for studies using current status data. This method is based on a Weibull survival model for a two‐group comparison. The Weibull model allows the investigator to specify a group difference in terms of a hazards ratio or a failure time ratio. We consider exponential, Weibull and uniformly distributed censoring distributions. We base our power calculations on a parametric approach with the Wald test because it is easy for medical investigators to conceptualize and specify the required input variables. As expected, studies with current status data have substantially less power than studies with the usual right‐censored failure time data. Our simulation results demonstrate the merits of these proposed power calculations. Copyright © 2009 John Wiley & Sons, Ltd.
Stage‐specific cancer incidence: An artificially mixed multinomial logit model
Authors: Chefo Solomon , Tsodikov Alex
Published: May 2009

Early detection of prostate cancer using the prostate‐specific antigen test led to a sharp spike in the incidence of the disease accompanied by an equally sharp improvement in patient prognoses as evaluated at the point of advanced diagnosis. Observed outcomes represent age at diagnosis and stage, a categorical prognostic variable combining the actual stage and the grade of tumor. The picture is summarized by the stage‐specific cancer incidence that represents a joint survival‐multinomial response regressed on factors affecting the unobserved history of the disease before diagnosis (mixture). Fitting the complex joint mixed model to large population data is a challenge. We develop a stable and structured MLE approach to the problem allowing for the estimates to be obtained iteratively. Factorization of the likelihood achieved by our method allows us to work with only a fraction of the model dimension at a time. The approach is based on generalized self‐consistency and the quasi‐EM algorithm used to handle the mixed multinomial part of the response through Poisson likelihood. The model provides a causal link between the screening policy in the population and the stage‐specific incidence. Copyright © 2009 John Wiley & Sons, Ltd.
Zinc in native tissues and cultured cell lines of human prostate studied by SR‐XRF and XANES
Authors: Podgórczyk M. , Kwiatek W. M. , Zaja̧c W. M. , Dulińska‐Litewka J. , Welter E. , Grolimund D.
Published: May 2009

During longlasting attempts to understand the aetiology of prostate cancer (CaP) on molecular level, attention has been paid to a unique capability of prostate epithelial cells to accumulate zinc. The latter plays role in a wide range of cellular processes such as the function of immune system, angiogenesis or apoptosis. Zinc has a significant antioxidant function, and its presence in prostate cells is strongly connected with their metabolism. This paper reports on the analysis of zinc concentration and oxidation level in the samples of human CaP tissues and cultured human prostate cell lines such as DU‐145, LNCaP and PC‐3, aided by x‐ray bioimaging. The study was performed by means of synchrotron radiation (SR) techniques. Bioimaging on cellular level, available through the SR x‐ray fluorescence (SR‐XRF) methods, applied to the samples of native prostate tissue, revealed a complexity of structures, while cell culture samples provided areas of homogeneity required for reliable analysis. SR‐XRF enabled us to establish the dependence of zinc concentration upon histological status of tissue (healthy, hyperplastic or cancerous). In‐depth studies of local chemical environment of an x‐ray absorbing zinc atom, including determination of Zn K‐edge position, were possible through the use of x‐ray absorption near edge structure (XANES) analysis. Copyright © 2009 John Wiley & Sons, Ltd.
A Mono‐Cobalt Substituted Wells–Dawson Phosphotungstate with an Antenna Ligand
Authors: Liu Hong‐Sheng , Peng Jun , Wang Li‐Xia
Published: May 2009

A mono‐cobalt substituted Wells–Dawson polyoxometalate with an antenna ligand linked to the CoII atom, was prepared by reaction of the mono‐vacant Wells–Dawson precursor [P2W17O61]10– with a imidazole‐cobalt complex by using the bench method. It was isolated as the imidazole salt: (HIm)7H[P2W17O61Co(Im)]·4H2O (1) (Im = imidazole). Compound 1 was characterized by elemental analysis, IR and UV/Vis spectroscopy, TG analysis, cyclic voltammetry and single‐crystal/powder X‐ray diffraction. This is the first example of the 3d transition metal mono‐substituted Wells–Dawson polyoxometalate with an antenna ligand.
Systematic review: photodynamic therapy for unresectable cholangiocarcinoma
Authors: Gao Fei , Bai Yu , Ma Shu‐Ren , Liu Feng , Li Zhao‐Shen
Published: May 2009

Background

Palliative therapies for unresectable cholangiocarcinoma such as stent, radiotherapy and chemotherapy have generally been disappointing. Therefore, it is necessary to find a new approach to fighting the disease. Several published clinical trials have reported the therapeutic effect of photodynamic therapy (PDT) for unresectable cholangiocarcinoma.

Objective

To assess the safety and efficacy of photodynamic therapy for patients with unresectable cholangiocarcinoma.

Methods

Relevant studies were retrieved from the Medline, Current Contents, Embase, and Cochrane Library databases. Inclusion of papers was determined by using a predetermined protocol; independent assessments and the final consensus decision were performed by two independent reviewers. Acceptable study designs included randomized controlled trials (RCTs), controlled clinical trials (CCTs), case studies, and case reports. Twenty studies met the inclusion criteria, and were tabulated and critically appraised in terms of characteristics, methods, outcomes, and complications.

Results

Twenty studies were included. The quality of the available evidence was low to moderate with the majority of studies being uncontrolled before and after design and thus limited by the retrospective nature of much of the available data. After PDT, it is reported that bilirubin serum levels declined, quality of life improved and survival time increased in most of the patients. At the same time, there were few complications.

Conclusions

Based on currently available evidence, PDT was safe and effective for patients with inoperable cholangiocarcinoma.
Neuroimaging findings in children with paediatric neurotransmitter diseases
Authors: Lee Wang‐Tso , Weng Wen‐Chin , Peng Shinn‐Forng , Tzen Kai‐Yuan
Published: May 2009

Paediatric neurotransmitter diseases consist of a group of inherited neurometabolic diseases in children, and include disorders related to γ‐amino butyric acid (GABA) metabolism, monoamine biosynthesis, etc. The diagnosis of paediatric neurotransmitter diseases remain a great challenge for paediatricians and child neurologists. In addition to clinical manifestations and CSF neurotransmitter measurement, neuroimaging findings can also be very informative for the diagnosis and evaluation of the patients. For patients with monoamine biosynthesis disorders, the functional evaluation of dopaminergic transmission also plays an important role. Understanding of the possible neuroimaging changes in paediatric neurotransmitter diseases is therefore of great value for the investigation of these patients.