bluuebunny/crossref_metadata_2025 huggingface dataset:
Ion trap mass analysis at high pressure: an experimental characterization
Authors: Song Qingyu , Xu Wei , Smith Scott A. , Gao Liang , Chappell William J. , Cooks R. Graham , Ouyang Zheng
Published: October 2009

In recent years, it has become increasingly interesting to understand the performance of mass spectrometers at pressures much higher than those employed with conventional operating conditions. This interest has been driven by several influences, including demand for the development of reduced‐power miniature mass spectrometers, desire for improved ion transfer into and through mass spectrometers, enhanced‐yield preparative mass separations, and mass filtering at the atmospheric pressure interface. In this study, an instrument was configured to allow for the performance characterization of a rectilinear ion trap (RIT) at pressures up to 50 mtorr with air used as the buffer gas. The mass analysis efficiency, mass resolution, isolation efficiency, and collision‐induced dissociation (CID) efficiency were evaluated at pressures ranging from 1 to 50 mtorr. The extent of degradation of mass resolution, isolation efficiency and ion stability as functions of pressure were characterized. Also, the optimal resonance ejection conditions were obtained at various pressures. Operations at 50 mtorr demonstrated improved CID efficiency in addition to peak widths of 2 and 5 m/z units (full width at half‐maximum, FWHM) for protonated caffeine (m/z 195) and Ultramark (m/z 1521) respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Impact of various food ingredients on the retention of furan in foods
Authors: Van Lancker Fien , Adams An , Owczarek Agnieszka , De Meulenaer Bruno , De Kimpe Norbert
Published: October 2009

Since furan is classified as “possibly carcinogenic to humans,” many studies investigated furan concentrations in foods. However, no data are available on the impact of food ingredients on the retention or release of furan from food. These data are important, since they explain the differences in furan removal during domestic food preparation. Furan retention was studied by spiking various samples with D4‐furan and comparing D4‐furan evaporation from these samples with comparable aqueous solutions. In addition, furan concentrations were determined. Furan retention caused by starch gels was negligible. Oils caused high furan retention: peak areas of furan in oils ranged from 22 to 25% of the corresponding aqueous solutions. In addition, in coffee, furan retention was mainly caused by the lipophilic fraction. However, since furan retention was also found in defatted coffee and coffee grounds, other coffee constituents also have the ability to retain furan. Peak areas of furan in the headspace of baby foods ranged from 71 to 97% of those in water. In addition, in this case, the highest retention was found in baby foods with added oils. Baby food containing spinach showed the highest furan concentration (172 ppb) as well as the highest furan retention.
3,3′‐Dihydroxyisorenieratene prevents UV‐induced formation of reactive oxygen species and the release of protein‐bound zinc ions in human skin fibroblasts
Authors: Lutter Kaya , De Spirt Silke , Kock Sebastian , Kröncke Klaus‐Dietrich , Martin Hans‐Dieter , Wagener Tanja , Stahl Wilhelm
Published: October 2009

3,3′‐Dihydroxyisorenieratene (DHIR) is a structurally unusual carotenoid exhibiting bifunctional antioxidant properties. It is synthesized by Brevibacterium linens, used in dairy industry for the production of red smear cheeses. The compound protects cellular structures against photo‐oxidative damage and inhibits the UV‐dependent formation of thymidine dimers. Here we show that DHIR prevents a UV‐induced intracellular release of zinc ions from proteins in human dermal fibroblasts. The effect is correlated with a decreased formation of intracellular reactive oxygen species. In contrast, zinc release from cellular proteins induced by hyperthermia is not affected by pretreatment of cells with the antioxidant DHIR. It is suggested that the intracellular zinc release upon UV irradiation is due to oxidative modifications of the zinc ligands in proteins (e.g. cysteine) and that protection by DHIR is due to intracellular scavenging of reactive oxygen species generated in photo‐oxidation.
Malaria. Die wichtigste tropische Infektionskrankheit
Authors: Stich August
Published: October 2009

Malaria ist eine der großen Seuchen der Menschheit! Nach Schätzungen der Weltgesundheitsorganisation erleiden jedes Jahr 500 bis 600 Millionen Menschen einen Malariaanfall, mehr als eine Million sterben. Die größte Last tragen Kinder im subsaharischen Afrika, wo die Malaria einen entscheidenden Anteil zur hohen Kindersterblichkeit beiträgt. Damit ist die Malaria die wichtigste tropische Infektionskrankheit.
Wirkstoffe gegen Malaria: Was ist in der Pipeline? Wenig Neues im Kampf gegen die Malaria
Authors: Schlitzer Martin
Published: October 2009

Der überwiegende Teil der Wirkstoffe in der klinischen Entwicklung entstammt zweier, seit längerem verwendeter Substanzklassen, den 4‐Aminochinolinen und den Endoperoxiden. Nur T3 und Fosmidomycin weisen neue Wirkmechanismen auf. Die Entwicklung geeigneter Wirkstoffe gegen Malaria ist kein leichtes Unterfangen – der Zustrom weiterer Testkandidaten wird spärlich bleiben.
Wirkstoffe zur Behandlung von Leishmaniosen. Antimon und mehr
Authors: Ryczak Jasmin , Kunick Conrad
Published: October 2009

Infektionen mit einzelligen Parasiten der Gattung Leishmania verursachen sehr unterschiedliche Krankheitsbilder. Obwohl in den ärmeren Ländern der Subtropen und Tropen mehr als 10 Millionen Menschen an diesen Erkrankungen leiden, wird ihnen in den Industrieländern wenig Aufmerksamkeit entgegengebracht. Die in der Vergangenheit relativ bescheidenen Forschungsaktivitäten zur Suche nach antileishmaniellen Wirkstoffen sind dafür verantwortlich, dass die aktuell verfügbaren Therapieoptionen begrenzt sind.
Die afrikanische Schlafkrankheit. Eine alte Bedrohung kehrt zurück
Authors: Stich August
Published: October 2009

Überraschend spät haben Öffentlichkeit und internationale Fachwelt ein Phänomen zur Kenntnis genommen, das sich bereits seit den 1960er Jahren auf dem afrikanischen Kontinent abzeichnet: die Rückkehr der Schlafkrankheit. Diese uralte Seuche Afrikas wurde in den Zeiten der Herrschaft kolonialer Regime erfolgreich zurückgedrängt. In den letzten zwei Jahrzehnten hat sie jedoch wieder epidemische Dimensionen erreicht und gilt heute bereits in einigen Regionen des Kongo oder Nord‐Angolas als eine der häufigsten Todesursachen junger Erwachsener.
Phosphated crosslinked pectin as a potential excipient for specific drug delivery: preparation and physicochemical characterization
Authors: Souto‐Maior João Fhilype Andrade , Reis Adriano Valim , Pedreiro Liliane Neves , Cavalcanti Osvaldo Albuquerque
Published: October 2009

Pectin was chemically modified with different amounts of trisodium trimetaphosphate (STMP) in aqueous solution (pH = 12), thereby giving a material with reduced water solubility. The physiochemical characterization of this new material was carried out through Fourier transform infrared and thermogravimetric analyses. Phosphated pectin (Pect‐STMP) together with prebiotic (oligosaccharide) were incorporated into an aqueous dispersion of polymethacrylate (Eudragit® RS 30 D) in order to obtain free films using a casting process (50 °C) on a Teflon plate. The free films were evaluated using water vapour transmission, average swelling index in simulated gastric fluid (SGF) and simulated intestinal fluid, scanning electron microscopy and a diffusion study with theophylline in buffer solution with and without pectinolytic enzyme. The results suggest that the new material can be used in the coating process for oral solid‐reservoir systems, to prevent the premature release of drugs in SGF (pH = 1.2). Furthermore, the presence of both Pect‐STMP and oligosaccharide favours the specific degradation of the pellicle by the action of the enzymes produced by colonic microflora. The material obtained in this work has the potential to be applied in devices for drug delivery in the colon, making possible modified release of drugs. Nevertheless, subsequent colon‐specific experiments in vivo need to be carried out in order to confirm the possible application of this new material. Copyright © 2009 Society of Chemical Industry
Proteome changes in human bronchoalveolar cells following styrene exposure indicate involvement of oxidative stress in the molecular‐response mechanism
Authors: Mörbt Nora , Mögel Iljana , Kalkhof Stefan , Feltens Ralph , Röder‐Stolinski Carmen , Zheng Jiang , Vogt Carsten , Lehmann Irina , von Bergen Martin
Published: October 2009

Styrene is a volatile organic compound that is widely used as an intermediate in many industrial settings. There are known adverse health effects at environmentally significant concentrations, but little is known about the molecular effect of exposure to styrene at sub‐acute toxic concentrations. We exposed human lung epithelial cells, at a wide range of concentrations (1 mg/m3–10 g/m3), to styrene and analyzed the effects on the proteome level by 2‐DE, where 1380 proteins spots were detected and 266 were identified unambiguously by MS. A set of 16 protein spots were found to be significantly altered due to exposure to styrene at environmentally significant concentrations of 1–10 mg/m3 (0.2–2.3 ppm). Among these, superoxide dismutase as well as biliverdin reductase A could be correlated with the molecular pathway of oxidative stress, while eukaryotic translation initiation factor 5A‐1, ezrin, lamin B2 and voltage‐dependent anion channel 2 have been reported to be involved in apoptosis. Treatment with styrene also caused the formation of styrene oxide–protein adducts, specifically for thioredoxin reductase 1. These results underline the relevance of oxidative stress as a primary molecular response mechanism of lung epithelial cells to styrene exposure at indoor‐relevant concentrations.
Synthesis and characterization of perfluoro‐3‐methylene‐2,4‐dioxabicyclo[3,3,0] octane: Homo‐ and copolymerization with fluorovinyl monomers
Authors: Mikes Frantisek , Teng Hongxiang , Kostov George , Ameduri Bruno , Koike Yasuhiro , Okamoto Yoshiyuki
Published: October 2009

The synthesis of perfluoro‐3‐methylene‐2,4‐dioxabicyclo[3,3,0] octane (D), its radical homopolymerization, and copolymerization with fluoroolefins are presented. Fluorodioxolane (D) was synthesized through direct fluorination of the corresponding hydrocarbon precursor in a fluorinated solvent by F2/N2 gas. It was polymerized in bulk using perfluorodibenzoyl peroxide as the initiator. The resulting homopolymer had a limited solubility in fluorinated solvents, and its glass transition temperature (Tg) was in the range of 180–190 °C. The polymeric films prepared by casting from hot hexafluorobenzene (HFB) solution were transparent with low refractive index (1.329 at 633 nm). These films were thermally stable (Td > 350 °C), and were hard and brittle. The copolymers of monomer (D) were prepared with fluorovinyl monomers such as chlorotrifluoroethylene (CTFE), perfluoropropyl vinyl ether, perfluoromethyl vinyl ether, and vinylidene fluoride. The kinetics of radical copolymerization of monomer (D) with CTFE led to the assessment of the reactivity ratios of both comonomers: rD = 3.635 and rCTFE = 0.737 at 74 °C, respectively. The copolymers obtained were soluble in HFB and perfluoro‐2‐butyltetrahydrofuran, with Tg in the range of 84–145 °C depending on the copolymer composition. The films of the copolymers were flexible and clear with a low refractive index (1.3350–1.3770 at 532 nm). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6571–6578, 2009
Organoboronium amphiphilic block copolymers
Authors: Cui Chengzhong , Bonder Edward M. , Jäkle Frieder
Published: October 2009

A new class of amphiphilic organometallic block copolymers with cationic organoboron pendant groups was developed. Selective replacement of one of the bromine substitutents on each boryl group of the block copolymer PSBBr2‐b‐PS with an organometallic reagent ArM (ArM = 2,4,6‐trimethylphenyl copper, 4‐t‐butylphenyltrimethyl tin) followed by treatment with 2,2′‐bipyridine gave the novel block copolymers [3Ar](Br)n as light yellow solid materials that show good stability in air and moisture and high solubility in most organic solvents. Their structure and composition were confirmed by multinuclear NMR, GPC, and elemental analysis. Highly regular micellar aggregates form in block‐selective solvents (e.g., MeOH, toluene) as demonstrated by 1H NMR, dynamic light scattering, and transmission electron microscopy. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6612–6618, 2009
Models for adhesion at weak polymer interfaces
Authors: Zhang Jianbin , Lodge Timothy P. , Macosko Christopher W.
Published: October 2009

The weak interfaces between immiscible polymer pairs typically fail through chain scission. The critical facture toughness for such interfaces is closely related to the density of intermolecular entanglements at the interface. From scaling analysis, a simple correlation between facture toughness and chain entanglement was developed. It predicts well the interfacial adhesion for many immiscible polymer pairs found in the literature. For an interface with block copolymer reinforcement, its critical fracture toughness comes from both intermolecular entanglements of homopolymers and copolymer bridges. In the chain scission regime (low copolymer coverage), the block copolymer contribution is found proportional to copolymer interfacial coverage, with the coefficient being the energy to stretch and break a copolymer chain. The chain‐breaking energy for different copolymers was evaluated and compared to literature data. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2313–2319, 2009
Poly(L‐lactide) crystallization induced by multiwall carbon nanotubes at very low loading
Authors: Xu Hong‐Sheng , Dai Xiujuan J. , Lamb Peter R. , Li Zhong‐Ming
Published: October 2009

Poly(L‐lactide) (PLLA)/multiwall carbon nanotube (MWNT) composites were prepared by the solvent‐ultrasonic‐casting method. Only very low concentrations of MWNTs (<0.08 wt %) were added in the composites. Isothermal and nonisothermal crystalline measurements were carried out on PLLA/MWNT composites to investigate the effect of MWNTs on PLLA crystalline behavior. DSC results showed that the incorporation of MWNTs significantly shortened the crystalline induction time and increased the final crystallinity of the composite, which indicated MWNTs have a strong nucleation effect on PLLA even at very low concentrations. The nonisothermal crystallization measurements showed that the MWNTs greatly speed up crystallization during cooling. From isothermal crystallization results, both PLLA and PLLA/MWNT composites samples closely followed a relationship based on Lauritzen‐Hoffman theory, with the regime II to III transition shifting to lower temperature with increasing MWNT concentration. A double melting peak appeared in both nonisothermal and isothermal measurements. The conditions under which it appeared were found to closely depend on the regime II‐III transition temperature obtained from Lauritzen‐Hoffman theory. From the magnitude and position of melting peaks, it is proposed that the double melting peak is caused by a disorder‐order crystal phase transition. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2341–2352, 2009
Small‐angle X‐ray scattering investigation of carbon nanotube‐reinforced polyacrylonitrile fibers during deformation
Authors: Wang Wenjie , Murthy N. Sanjeeva , Chae Han Gi , Kumar Satish
Published: October 2009

Structural changes during deformation in solution‐ and gel‐spun polyacrylonitrile (PAN) fibers with multi‐ and single‐wall carbon nanotubes (CNTs), and vapor‐grown carbon nanofibers were investigated using synchrotron X‐ray scattering. Previously published wide‐angle X‐ray scattering (WAXS) results showed that CNTs deform under load, alter the response of the PAN matrix to stress, and thus enhance the performance of the composite. In this article, we find that the elongated scattering entities that give rise to the small‐angle X‐ray scattering (SAXS) in solution‐spun fibers are the diffuse matrix‐void interfaces that follow the Porod's law, and in gel‐spun fibers these are similar to fractals. The observed smaller fraction of voids in the gel‐spun fibers accounts for the significant increase in the strength of this fiber. The degree of orientation of the surfaces of the voids is in complete agreement with those of the crystalline domains observed in WAXS, and increases reversibly upon stretching in the same way as those of the crystalline domains indicating that the voids are integral parts of the polymer matrix and are surrounded by the crystalline domains in the fibrils. The solution‐spun composite fibers have a larger fraction of the smaller (<10 nm) voids than the corresponding control PAN fibers. Furthermore, the size distribution of the voids during elongation changes greatly in the solution spun PAN fiber, but not so in its composites. The scattered intensity, and therefore the volume fraction of the voids, decreases considerably above the glass transition temperature (Tg) of polymer. Implications of these observations on the interactions between the nanotubes and the polymer are discussed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2394–2409, 2009
Ferroelectric poly(vinylidene fluoride) PVDF films derived from the solutions with retainable water and controlled water loss
Authors: Li Xue , Chen Shuting , Yao Kui , Tay Francis Eng Hock
Published: October 2009

To obtain β‐phase dominant ferroelectric poly(vinylidene fluoride) (PVDF) homopolymer thin films on aluminum‐coated silicon substrates, the retaining and loss of water were manipulated by introducing several hydrated and hygroscopic chemicals in the precursor solutions, including aluminum nitrate nonahydrate, aluminum chloride hexahydrate, chromium nitrate nonahydrate, tetra‐n‐butylammonium chloride, and one hygroscopic but nonhydrated chemical, ammonium acetate. Their ability of retaining water during the thermal annealing of the films and the relationship between water retaining and the effects on promoting the β phase were investigated. The results showed an ideal scenario was that the added hydrated salts should be able to retain substantial amount of water during the PVDF crystallization to effectively promote the β phase but completely dehydrate or decompose at the further elevated annealing temperature in order to obtain β‐phase dominant PVDF film without substantially incorporating water and deteriorating the electrical properties. As one of the hydrated chemicals well satisfying the above requirements, Al(NO3)3·9H2O, of different amounts was introduced to the PVDF precursor solutions and the optimal resulting β‐phase dominant ferroelectric PVDF thin films exhibited smooth morphology, low dielectric loss, high remnant polarization of 89 mC/m2, and large effective piezoelectric coefficient d33 of −14.5 pm/V (under the clamping of the substrate). © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2410–2418, 2009
Experiencing one's body after a diagnosis of cancer—a phenomenological study of young adults
Authors: Snöbohm Christina , Friedrichsen Maria , Heiwe Susanne
Published: October 2009

Young adults with cancer are still in the process of shaping their lives and are therefore at a vulnerable stage. Altered body image may change how patients cope with the disease and impact rehabilitation capacity.

Objective: To describe the essence of how young adults with cancer experience their bodies.

Methods: Interviews (12 informants), transcribed verbatim. Analysis: Giorgi's phenomenological method.

Results: Identified themes: experience of ‘physical body change’, ‘discomfort’, ‘the body at the moment without reflecting on the disease and treatment’, ‘body image’ and ‘grasping the illness’. Essences: The body as the bearer of life; conflict between age and disease; manifest changes in appearance, physically and mentally; the body no longer a whole; the body as influenceable and able to recover and heal.

Conclusions: These patients undergo physical and mental changes that affect their self‐image and health‐related life quality. Thus, future studies need to explore interventions that may enhance the individualś perception of their body. Copyright © 2009 John Wiley & Sons, Ltd.
The impact of optimism on anxiety, depression and quality of life in urogenital cancer patients
Authors: Zenger Markus , Brix Christina , Borowski Johannes , Stolzenburg Jens‐Uwe , Hinz Andreas
Published: October 2009

Objective: The purpose of the present study was to examine the relationship between optimism and anxiety, depression and health‐related quality of life (HRQOL). A further aim was to investigate the predictive value of optimism for anxiety, depression and HRQOL, quantified with and without controlling the corresponding base level.

Methods: A total of 427 urogenital cancer patients were asked to complete the Life Orientation Test (LOT), the Hospital Anxiety and Depression Scale (HADS) and the health survey SF‐8 during their stay in the hospital (T1), two weeks later (T2) and three months later.

Results: Finally, 275 patients (64.4%) completed all questionnaires. Optimism at T1 was significantly associated with anxiety (r=−0.35), depression (r=−0.41) and HRQOL (physical: r=0.29; mental: r=0.27) and can predict outcome variables three months later. After controlling for the base levels of anxiety, depression and HRQOL, the predictive value of optimism remained significant but small. The incrementally variance explained by the LOT varied between 2.1% in anxiety and 8.2% in physical HRQOL.

Conclusion: Especially patients with a low level of optimism and a high level of pessimism are at risk for higher levels of anxiety and depression in addition to lowered HRQOL. Copyright © 2009 John Wiley & Sons, Ltd.
The Posttraumatic Growth Inventory: an examination of the factor structure and invariance among breast cancer survivors
Authors: Brunet Jennifer , McDonough Meghan H. , Hadd Valerie , Crocker Peter R. E. , Sabiston Catherine M.
Published: October 2009

Objective: The present study tested the proposed five‐factor structure and invariance of the Posttraumatic Growth Inventory (PTGI; Tedeschi & Calhoun, 1996) in a sample of physically active breast cancer survivors.

 Methods: A sample of breast cancer survivors (N=470, Mage=57.3, SD=7.8 years) completed the PTGI and a demographic questionnaire. The factor structure, factorial invariance, and latent mean invariance were tested using maximum likelihood structural equation modeling.

 Results: Preliminary analyses showed acceptable reliability for the PTGI subscales (α<0.83). Confirmatory factor analysis (CFA) supported the five related factors corresponding to: relating to others, new possibilities, personal strength, spiritual change, and appreciation of life (χ2(179)=822.53, CFI=0.97, NNFI=0.96, SRMR=0.05, RMSEA=0.09). Multigroup CFA supported the invariance of the PTGI across age groups, treatment type, time since diagnosis, and time since last treatment.

 Conclusions: These findings provide support for (1) the multidimensional nature and factorial validity of the PTGI, and (2) the use of the PTGI in future research examining posttraumatic growth within samples of physically active breast cancer survivors. Copyright © 2009 John Wiley & Sons, Ltd.
Quality‐of‐life and surgical treatments for rectal cancer—a longitudinal analysis using the California Cancer Registry
Authors: Smith‐Gagen Julie , Cress Rosemary D. , Drake Christiana M. , Romano Patrick S. , Yost Kathleen J. , Ayanian John Z.
Published: October 2009

Background: Heterogeneous results for research investigating health‐related quality of life (HRQL) in patients undergoing sphincter‐ablating procedures for rectal cancer are likely due to single institution experiences and measurement of HRQL. To address this heterogeneity, we evaluated HRQL in patients with rectal cancer by type of surgery, location of tumor, and receipt of adjuvant therapy using an HRQL instrument that has not been used to address rectal cancer patients in a population‐based sample over time.

Methods: The Functional Assessment of Cancer Therapy‐Colorectal instrument was administered at 9 and 19 months after diagnosis to a consecutive sample of 160 patients in Northern California identified by the California Cancer Registry. A broad multidimensional interpretation of HRQL was used to examine the impact of tumor location and treatment status, stage of disease, age, and gender.

Results: In general, men had lower social well‐being scores, and younger patients had lower physical and emotional well‐being scores and colorectal concerns scores. We found no differences in HRQL by either tumor location or type of surgery, at either 9 or 19 months after diagnosis. Lower physical well‐being and greater adverse colorectal concerns were reported at 9 months among patients who received adjuvant therapy; however, only adverse colorectal concerns persisted over time.

Conclusions: This study provides additional evidence that sphincter‐ablating procedures do not necessarily reduce quality of life in patients with rectal cancer. Distinctive features of this study include a broad multidimensional interpretation of HRQL, the 19 months of longitudinal follow‐up, and a prospective population‐based study design. Copyright © 2009 John Wiley & Sons, Ltd.
Is the Rotational Temperature of OH(A–X) for Discharges in and in Contact with Liquids a Good Diagnostic for Determining the Gas Temperature?
Authors: Bruggeman Peter , Schram Daan C. , Kong Michael G. , Leys Christophe
Published: October 2009

In this paper the rotational temperature of OH(A–X) and rotational population distribution of OH(A) are investigated for streamer discharges in bubbles and glow discharges with liquid electrodes, both at atmospheric pressure. The influence of the filling gas is investigated in detail and the non‐Boltzmann nature of the rotational population distributions is discussed. It is shown that the rotational population distribution of OH(A) is even at atmospheric pressure an image of the formation process or is at least influenced by it. As a consequence the rotational temperature is in this case not a good estimate of the gas temperature as the rotational population distribution is not an image of a kinetic temperature. In some cases rotational states with small rotational numbers offer a possibility to obtain the gas temperature. The influence of these results on the determination of gas temperatures in the field of liquid plasmas is discussed.

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Both nongenomic and genomic effects are involved in estradiol's enhancing the phenotype of smooth muscle cells in cultured prostate stromal cells
Authors: Zhang Zhisong , Wang Liang , Mei Mei , Zhu Yan , Du Xiaoling , Lee Chung , Park Irwin , Zhang Ju , Shi Jiandang
Published: October 2009

BACKGROUND

Stromal smooth muscle cells (SMCs) play an important role in the pathogenesis and clinical symptom of benign prostatic hyperplasia. We had reported that estrogen enhances the phenotype of SMC in cultured prostate stromal cells (PRSCs). Here we further investigate the mechanism by which estrogen affects the differentiation of PRSCs.

METHODS

Primary cultured PRSCs were stimulated with E2 or BSA‐E2. The mRNA level of SMC‐specific genes, smoothelin, and SM‐MHC were measured by qRT‐PCR. The SM‐MHC protein was measured by Western blot. The mRNA and protein levels of TGF‐β1 were measured by qRT‐PCR and ELISA. The MAPK inhibitor PD98059, the estrogen receptor antagonist ICI182,780 and neutralizing antibody to TGF‐β1 were used to reveal the mechanism of estrogen effect.

RESULTS

E2 and BSA‐E2 significantly up‐regulate the expression of SMC‐specific genes in PRSCs. Both forms of estrogen could increase the expression of TGF‐β1, which can be blocked by pre‐treating with PD98059. Moreover, PD98059 and TGF‐β1 neutralizing antibody could abrogate the effect of BSA‐E2 on cell differentiation. However, they could only inhibit part of E2‐induced SMC phenotype enhancement. ICI182,780 could partially suppress the pro‐differentiation effect of E2 but had no influence on the effect of BSA‐E2. Combined treatment with ICI182,780 and PD98059 can completely abrogate the effect of E2.

CONCLUSIONS

Estrogen could promote the expression of TGF‐β1 in PRSCs through nongenomic activation of MAPK pathway, and in turn enhance the SMC phenotype. Besides for this nongenomic effect, estrogen can also enhance the SMC phenotype through classical genomic action. Prostate 70: 317–332, 2010. © 2009 Wiley‐Liss, Inc.
Optical and electrical properties of Nd‐doped BiFeO3 thin films and heterostructures
Authors: Vengalis Bonifacas , Devenson Jelena , Oginskis Antanas K. , Lisauskas Vaclovas , Anisimovas Fiodoras , Butkute Renata , Dapkus Leonas
Published: October 2009

High quality BiFeO3 (BFO) and Bi0.9Nd0.1FeO3 (BNFO) thin films (d = 150‐350 nm) were grown at 650‐750°C by RF sputtering on dielectric (SrTiO3; ZrO2) and conducting (Nb‐doped SrTiO3(100); n‐type Si) substrates. A direct band gap at 2.57 eV and 2.62 eV (at T =295 K) have been estimated for the BFO/YSZ and BNFO/YSZ films from optical transmittance spectra while an unset of weak absorption has been indicated for the films at 2.20 eV. Transverse electrical transport of the (BFO, BNFO)/(STON, Si) heterostructures revealed nonlinear current versus voltage behavior and clearly defined rectifying properties. Schottky junction model has been applied for the heterojunctions at T =300 K although complicated shape of I‐U curves demonstrated increasing role of space charge limited current with T decreasing down to 78 K. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High speed photoswitching: from material properties to device performances
Authors: Roux J.‐F. , Delord J.‐M. , Coutaz J.‐L.
Published: October 2009

In this paper we show how the characteristics of semiconductor (SC) material with very short carriers trapping time impact the performances of ultrafast optoelectronic devices used for generation and detection of radiofrequency or TeraHertz signals. The impact of properties such as concentration of deep‐level trapping centres, free carrier drift velocity saturation and long time relaxation of deep‐level trapping centres are studied. For devices based on low‐temperature grown GaAs we observe that working above typical ratings in term of input optical power, laser repetition rate or biasing electrical field lead, to reduction of electrical signal bandwidth and amplitude and linearity of RF signal samplers. All our experimental results are sustained by numerical simulations that allow us to quantify the limitations induced by SC material properties. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of photoconductivity and mobility in TlBr
Authors: Kažukauskas Vaidotas , Ziminskij Andžej , Davidyuk Georgyi , Bozhko Vladimir , Mironchuk Galina
Published: October 2009

We have investigated photoconductivity and mobility in TlBr from –30 ΩC up to +20 ΩC, where the ionic conductivity is pronounced. Mobility‐related conductivity maximum superimposed on an interband‐generation conductivity growth was observed. It could be caused by the recharge of the scattering centre at about 1.65 eV. From spectral dependencies defect‐related transitions at 0.55; 0.83, 1.1; 1.32 and 1.65 eV were identified, being dependent on sample prehistory, i.e., its excitation by light and/or voltage. The transient photocurrent kinetics has demonstrated a complex behaviour that could be explained by the combined influence of electron generation/recombination processes superimposed upon the ionic conductivity. The thermally activated ionic conductivity was still effective at –20 ΩC. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of effective charge carrier mobility in ZnPc/C60 solar cells after ageing
Authors: Kažukauskas Vaidotas , Arlauskas Andrius , Pranaitis Mindaugas , Lessmann Rudolf , Riede Moritz , Leo Karl
Published: October 2009

We have investigated the ageing of ZnPc/C60 solar cells in terms of changes of the charge carrier mobility and potential barrier height. The initial fast degradation of device performance within several hours was followed by a much slower one. The mobility decreases during degradation by about 30 to 50%. Moreover, an increase of the effective barrier height at ZnPC/C60 interface from ∼0.55 eV up to ∼0.65 eV was observed. Meanwhile thermal activation energy values of the electrical conductivity grew from about 0.28 eV to about 0.34 eV after ageing. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The 1,3 dipolar cycloaddition of azomethine ylides to graphene, single wall carbon nanotubes, and C60
Authors: Denis Pablo A. , Iribarne Federico
Published: October 2009

Herein, we perform a comparative study on the addition of azomethine ylides to graphene, carbon nanotubes, C60, ethene, pyrene and a C48H18 hydrocarbon. The calculated binding energies and free energy corrections suggest that the addition of azomethine ylide to perfect graphene is not spontaneous (ΔG > 0). However, the presence of Stones–Wales defects significantly increases reactivity: the binding energy between SW‐defective graphene and the azomethine ylide is 0.83 eV, close to that determined for a (5,5) SWCNT. The electronic properties of the sheet are not modified by the 1,3 cycloaddition. The binding energies determined for the addition of an azomethine ylide to a (5,5) SWCNT are significantly lower than previously reported. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Lineage Enforcement by Inductive Mesenchyme on Adult Epithelial Stem Cells across Developmental Germ Layers
Authors: Taylor Renea A. , Wang Hong , Wilkinson Sarah E. , Richards Michelle G. , Britt Kara L. , Vaillant François , Lindeman Geoffrey J. , Visvader Jane E. , Cunha Gerald R. , St. John Justin , Risbridger Gail P.
Published: October 2009

During development, cell differentiation is accompanied by the progressive loss of pluripotent gene expression and developmental potential, although de-differentiation in specialized cells can be induced by reprogramming strategies, indicating that transdifferentiation potential is retained in adult cells. The stromal niche provides differentiating cues to epithelial stem cells (SCs), but current evidence is restricted to tissue types within the same developmental germ layer lineage. Anticipating the use of adult SCs for tissue regeneration, we examined if stroma can enforce lineage commitment across germ layer boundaries and promote transdifferentiation of adult epithelial SCs. Here, we report tissue-specific mesenchyme instructing epithelial cells from a different germ layer origin to express dual phenotypes. Prostatic stroma induced mammary epithelia (or enriched Lin−CD29HICD24+/MOD mammary SCs) to generate glandular epithelia expressing both prostatic and mammary markers such as steroid hormone receptors and transcription factors including Foxa1, Nkx3.1, and GATA-3. Array data implicated Hh and Wnt pathways in mediating stromal-epithelial interactions (validated by increased Cyclin D1 expression). Other recombinants of prostatic mesenchyme and skin epithelia, or preputial gland mesenchyme and bladder or esophageal epithelia, showed foci expressing new markers adjacent to the original epithelial differentiation (e.g., sebaceous cells within bladder urothelium), confirming altered lineage specification induced by stroma and evidence of cross-germ layer transdifferentiation. Thus, stromal cell niche is critical in maintaining (or redirecting) differentiation in adult epithelia. In order to use adult epithelial SCs in regenerative medicine, we must additionally regulate their intrinsic properties to prevent (or enable) transdifferentiation in specified SC niches.

Disclosure of potential conflicts of interest is found at the end of this article.
Ethanol and PTZ effects on siRNA‐mediated GABAB1receptor: Down regulation of intracellular signaling pathway in prenatal rat cortical and hippocampal neurons
Authors: Naseer M.I. , Lee H.Y. , Ullah N. , Ullah I. , Park M.S. , Kim S.H. , Kim M.O.
Published: October 2009

GABABreceptors (R) are widely expressed and distributed in the nervous system, and have been implicated in variety of neurodegenerative and pathophysiological disorders. However, the exact molecular mechanism regarding responsibility of GABAB1R in downstream signaling pathway is not well understood. The present study was undertaken to explore the downstream signaling and role of GABAB1R upon acute ethanol and pentylenetetrazol (PTZ) exposure for (20 min) in cortical and hippocampal neuronal cell cultures by using GABAB1R RNA interference (i) (30 nM, 48 h) at gestational days 17.5. The results showed that GABAB1R and protein kinase A‐α (PKA) showed decreased expression upon ethanol and PTZ exposure in cortical and hippocampal neurons during transfected and nontransfected conditions, whereas these effects could lead to significant changes in phosphorylation of cAMP‐response element binding protein (p‐CREB) expression where GABAB1R was knocked down. Furthermore, intracellular Ca+2concentrations were also reduced in some groups after transfection with GABAB1R RNAi. These results showed a critical role of GABAB1R upon ethanol and PTZ exposure by modulating downstream signaling pathway. Finally, these findings suggested that inhibition of GABAB1R results in the modulation of PKA, p‐CREB pathway may play a role in long‐term changes in the nervous system, and may be an underlying cause of ethanol's effects. Synapse 64:181–190, 2010. © 2009 Wiley‐Liss, Inc.
An end‐to‐end framework of transport layer mobility management
Authors: Wu Yi , Le Yanqun , Zhang Dongmei
Published: October 2009

As an end‐to‐end transport layer mobility solution, the TCP Migrate allows mobile nodes to remain reachable and retain existing connections while changing their point of attachment (i.e., IP address) to the Internet. However, our study shows that the referenced transport layer mobility solution has to face a challenge of simultaneous movements which may also exist in MIPv6 with route optimization. In this paper we extend the TCP Migrate work by resolving the simultaneous mobility issue that the existing transport layer approaches lack of and propose an improved end‐to‐end framework of TCP Migrate scheme with an efficient DNS assistant for handover redirection and transmission resuming. The handover performance of the proposed scheme has been evaluated by ns‐2 simulations. Copyright © 2009 John Wiley & Sons, Ltd.
Les complications urinaires des traumatismes du bassin: aspects anatomocliniques et thérapeutiques au CHU de Conakry, Guinée
Authors: Bah I. , Bobo Diallo A. , Camara T. , Bah M. L. , Diallo T. M. O. , Amougou B. , Kouyaté K. , Bobo Diallo M.
Published: October 2009

Objectif

Ressortir les aspects anatomocliniques et évaluer les résultats thérapeutiques d’une série de complications urinaires des traumatismes du bassin suivie au service d’urologie-andrologie du CHU de Conakry.

Matériel et méthode

Il s’agit d’une étude rétrospective colligeant 52 cas de complications urinaires des traumatismes du bassin sur une période de cinq ans.

Résultats

Les complications urinaires des traumatismes du bassin représentaient 3 % de l’ensemble des hospitalisations durant la période d’étude. L’âge moyen de nos patients était de 33 ans, avec des extrêmes de 10 et 63 ans. Les traumatismes étaient dus aux accidents de la voie publique dans 54,9 % des cas. Sur le plan clinique, la symptomatologie était essentiellement constituée par la rétention aiguë d’urines avec 80,7 % des cas et d’hémorragie (hématurie et urétrorragie). La principale complication urinaire observée après le traumatisme du bassin était une lésion de l’urètre postérieur, avec 82,7 % des cas. Tous les patients ont bénéficié d’un traitement chirurgical. Les résultats thérapeutiques ont été jugés après un recul moyen de 52 mois sur les plans urinaire et sexuel. Ainsi, sur le plan urinaire, les résultats ont été jugés bons dans 59,6 % des cas, moyens dans 17,3 % et mauvais dans 23,1 % des cas. Sur le plan sexuel, on a noté que 53,8 % (n= 28) des patients ne présentaient pas de dysfonction érectile, 25 % (n= 13) des patients avaient une dysfonction modérée et 21,2 % (n= 11) une dysfonction sévère.

Conclusion

La prise en charge des complications urinaires des traumatismes du bassin est controversée, cependant, nous insistons sur la nécessité d’une étroite collaboration avec les orthopédistes, car la stabilisation des fractures du bassin constitue un élément capital de cette prise en charge.
Petrogenesis and tectonic implications of Late Mesozoic granites in the NE Yangtze Block, China: further insights from the Jiuhuashan–Qingyang complex
Authors: XU XI-SHENG , SUZUKI KAZUHIRO , LIU LEI , WANG DE-ZI
Published: October 2009

The Jiuhuashan–Qingyang complex is one of the Mesozoic granite complexes in the NE Yangzte Block, China. New petrographical and petrochemical data show that the complex comprises a dominant granodiorite–monzogranite, the Qingyang body, which was intruded by the Jiuhuashan granite body. The two are characterized by distinct mineral components and trace element patterns. Compared to the Qingyang granodiorite and monzogranite, the Jiuhuashan granite is enriched in Rb, Th, U, Nb, Ta, Hf, Yb and Lu, and depleted in Ba, Sr, Nd, Sm, Eu, Gd and Ti, which are ascribable to the separation of plagioclase and biotite, and crystallization of thorite and fergusonite during the magmatism. New LA-ICPMS zircon U–Pb dating suggests that the crystallization age of the Qingyang body is 139–133 Ma, and the Jiuhuashan granite followed at 127 Ma. Moreover, the new zircon U–Pb dates reveal that Archaean materials were involved in the formation of these magmas, and that a sodium-rich metasomatic event occurred at about 100 Ma. The CHIME monazite and zircon ages studied for the Jiuhuashan body agree well with the LA-ICPMS zircon ages. Integrating this information with previous studies for granites in the NE Yangtze Block and in the coastal area of SE China, we believe that all of these Late Mesozoic granites were produced under the tectonic regime of palaeo-Pacific plate subduction towards the SE China continent in a NW direction, but the granites in the NE Yangtze Block are basically derived by crustal melting with limited mixing of juvenile material during the magma generation.
Proceedings of the Forty-first Meeting of the Agricultural Research Modellers' Group
Authors: CROMPTON L. A. , WHEELER T. R.
Published: October 2009

This group, which is concerned with the applications of mathematics to agricultural science, was formed in 1970 and has since met at approximately yearly intervals in London for one-day meetings. The forty-first meeting of the group, chaired by Dr Derek Rose of the School of Agriculture, Food and Rural Development, University of Newcastle upon Tyne, was held in the Kohn Centre at the Royal Society, 6–9 Carlton House Terrace, London, on Friday, 3 April 2009 when the following papers were read.
Dispersion properties of electrostatic oscillations in quantum plasmas
Authors: ELIASSON BENGT , SHUKLA PADMA KANT
Published: October 2009

We present a derivation of the dispersion relation for electrostatic oscillations in a zero-temperature quantum plasma, in which degenerate electrons are governed by the Wigner equation, while non-degenerate ions follow the classical fluid equations. The Poisson equation determines the electrostatic wave potential. We consider parameters ranging from semiconductor plasmas to metallic plasmas and electron densities of compressed matter such as in laser compression schemes and dense astrophysical objects. Owing to the wave diffraction caused by overlapping electron wave function because of the Heisenberg uncertainty principle in dense plasmas, we have the possibility of Landau damping of the high-frequency electron plasma oscillations at large enough wavenumbers. The exact dispersion relations for the electron plasma oscillations are solved numerically and compared with the ones obtained by using approximate formulas for the electron susceptibility in the high- and low-frequency cases.
Sir George Strong Nares (18311915)
Authors: Deacon Margaret , Savours Ann
Published: October 2009

Nares is perhaps best known as the commander of the Challenger expedition from 1872 to 1874, a voyage of exploration which, it has been said, laid the foundations of almost every branch of oceanography as we know it today (British Museum, 1973). He also achieved fame as commander of the British Arctic Expedition of 187576, and as the author of Seamanship, which went through many editions in the second half of the 19th century. He is a fine example of the serving naval officer in the tradition of Parry, Franklin and Ross, one who could combine a naval career with a broad interest in science and the active pursuit of geographical exploration.
Norwegian-Canadian Svalbard Expedition, winter 1975
Authors: Berkey F. T. , Harang O. E.
Published: October 2009

Current theories and observations in magnetospheric physics suggest that low-energy particle fluxes, exhibiting the characteristics of solar-wind particles, have direct access to certain regions of the high-latitude polar ionosphere (Akasofu and Lanzerotti, 1975). The precipitation of these particles occurs over a few degrees of latitude and several hours of magnetic time (centred on geomagnetic noon) and this region has been termed the dayside magnetospheric cleft (Vasyliunas, 1974). The resultant phenomena, such as dayside auroral emissions, have not been extensively studied due to the rather remote location of accessible land mass at latitudes high enough for observations at local apparent noon to be made (Fig 1). Magnetospheric cleft observations have been carried out from instrumental aircraft (Whalen and Pike, 1973) and from Cape Parry, NWT (Peterson and Shepherd, 1974) in previous winters. Aircraft observations are, obviously, of limited duration and twilight at Cape Parry severely restricts photometric observations.
The first attempts at motor transport in Antarctica, 1907–1911
Authors: Dibbern J. Stephen
Published: October 2009

One of the most spectacular achievements during the late 1950's was the attainment of the South Pole and the subsequent crossing of Antarctica by Vivian Fuchs with the support of Edmund Hillary. Both parties reached the pole driving over-snow vehicles ranging from modified farm tractors to mechanically complex Sno-cats. The first and last bases on the crossing were named after Scott and Shackleton, in honour of Britain's two most celebrated names during the ‘heroic age’ of Antarctic exploration. The fact that it was Shackleton and Scott who introduced the ‘motor age’ to Antarctica is perhaps even more significant. Their attempts to introduce motor transport to Antarctica make an interesting footnote to their famous exploits.
Counting Harp Seals with ultra-violet photography
Authors: Lavigne D. M.
Published: October 2009

The Harp Seal Pagophilus groenlandicus is a gregarious, migratory seal inhabiting Arctic and sub-Arctic waters of the North Atlantic Ocean. In spring, asthe ice recedes, the largest of three known breeding populations migrates up the east coas of Canada from the Gulf of St Lawrence, along the coast of Labrador, to the Canadian Archipelago, Hudson Bay, and the west coast of Greenland. After spending the summer feeding in Arctic waters, the seals move southward ahead of the Arctic ice pack, reaching the coast of Labrador and the Gulf of St Lawrence sometime in late December or early January. They reappear at the end of February and in early March in whelping ‘patches’ or concentrations on ice inthe Gulf of St Lawrence west of the Magdalen Islands, and off the coast of Labrador in an areaknown as the ‘Front’. One of the two smaller and probably distinct breeding populations is to be found in the White Sea, the other in the Vestisen [West Ice] between Jan Mayen and Svalbard.