bluuebunny/crossref_metadata_2025 huggingface dataset:
Kräfte im Nano‐ und Pikonewtonbereich messen
Authors: Brand Uwe , Nesterov Vladimir
Published: April 2009

In der Biophysik, Pharmazie und Medizin werden seit einigen Jahren sehr feine Kraftmessungen an einzelnen Zellen, Molekülen oder Proteinen ausgeführt. Hieraus lassen sich viele Eigenschaften dieser Objekte ableiten. Für diese Manipulationen verwendet man Rasterkraftmikroskope. Doch die gemessenen Kräfte sind meist mit einer großen Unsicherheit behaftet. An der Physikalisch‐Technischen Bundesanstalt (PTB) in Braunschweig haben wir eine empfindliche Messeinrichtung entwickelt, mit der sich Kräfte im Nano‐ und Pikonewtonbereich zuverlässig messen lassen.
Der Körper als Wärmemaschine
Authors: Müller Andreas
Published: April 2009

Die Serie Fermis Corner bringt physikalische Aufgaben aus dem Alltag, die sich durch einfaches Abschätzen lösen lassen. Bislang folgte die Lösung einer jeweiligen Aufgabe erst im darauf folgenden Heft. Zukünftig werden wir dies ändern. Die Serie wird in lockerer Folge erscheinen und die Lösung im Anschluss an die Frage präsentiert. Hier die Lösung aus dem letzten Heft.
On the influence of unsaturation on the macrolactonization of hydroxy fatty acids
Authors: Caruso Tonino , Donnamaria Carmen , Artillo Antonietta , Peluso Andrea , Spinella Aldo , Monaco Guglielmo
Published: April 2009

Regioselectivity and yields of Yamaguchi cyclization of (15S,16S)‐15,16‐dihydroxy‐otadecyl‐(6Z,9Z,12Z)‐trienoic acid and its saturated homologue have been compared at different temperatures and concentrations. For the unsaturated species the regioselectivity of cyclization depends on temperature to such an extent that the preferred regioisomer changes as the temperature changes, whereas for the saturated homologue the even‐membered ring turns out to be always the preferred one. Molecular mechanics is used to interpret these findings. For both dihydroxyacids, there is experimental evidence that the yields of the two monocyclic regioisomers are thermodynamically controlled, unlike those of the analogue monohydroxy lactones. The higher cyclization yield of the unsaturated monohydroxyacid is interpreted in terms of conformational pre‐organization. Copyright © 2009 John Wiley & Sons, Ltd.
Structure and properties of the nanocomposite films of chitosan reinforced with cellulose whiskers
Authors: Li Qian , Zhou Jinping , Zhang Lina
Published: April 2009

Bio‐based nanocomposite films were successfully developed using cellulose whiskers as the reinforcing phase and chitosan as the matrix. Cellulose whiskers, with the lengths of 400 ± 92 nm and diameters of 24 ± 7.5 nm on average, were prepared by hydrolyzing cotton linter with sulfuric acid solution. The effects of whisker content on the structure, morphology and properties of the nanocomposite films were characterized by SEM, XRD, FTIR, UV‐vis spectroscopy, DMA, TG, tensile testing, and swelling experiment. The results indicated that the nanocomposites exhibited good miscibility, and strong interactions occurred between the whiskers and the matrix. With increasing whisker content from 0 to 15–20 wt %, the tensile strength of the composite films in dry and wet states increased from 85 to 120 MPa and 9.9 to 17.3 MPa, respectively. Furthermore, the nanocomposite films displayed excellent thermal stability and water resistance with the incorporation of cellulose whiskers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1069–1077, 2009
Compression elastic modulus of neutral, ionic, and amphoteric hydrogels based on N‐vinylimidazole
Authors: Valencia Joaquin , Baselga Juan , Pierola Ines F.
Published: April 2009

Several hydrogels of N‐vinylimidazole and sodium styrenesulfonate have been prepared by radical cross‐linking copolymerization in aqueous solution, using N,N′‐methylene‐bisacrylamide as crosslinker. Depending on composition, these hydrogels were neutral, amphoteric, cationic or anionic. Compression‐strain measurements were performed on samples as‐synthesized and swollen in deionized water or in acid aqueous solutions, with and without salt. It was thus found that the cross‐linking densities determined by compression measurements on as‐synthesized samples are in good accordance with those calculated by means of the model of polymer networks with pendant vinyl groups. A non‐Gaussian parameter (β) was introduced to explain that the elastic moduli (G) of samples swollen at equilibrium are larger than predicted by the Gaussian model. The β values of the neutral or ionized systems increase with swelling and fall into a single curve, which denotes a common behavior. Swelling has two opposite effects on G; on the one hand G decreases because the polymer volume fraction diminish and the system shifts from the affine limit to the phantom one; on the other, β increases and contributes to increasing G. The balance of those two opposite effects determines the variation of G with swelling. The possible contribution of ionic crosslinks to νe for the polyampholyte and for the polycation wearing divalent counteranions was discussed. A peculiar system is poly(sodium styrenesulfonate), whose cross‐linking density is much lower than expected. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1078–1087, 2009
Reinforcement of solid‐melt interfaces for semicrystalline polymers in a sequential two‐staged injection molding process
Authors: Jiang Genjie , Wu Hong , Yan Bowen , Guo Shaoyun , Huang Jian
Published: April 2009

The solid‐melt interfaces between polyethylene (PE) and polyamide 6 (PA6) reinforced by in situ reactive compatibilization in a sequential two‐staged injection molding process has been studied in this work. The effects of the maleic anhydride grafted PE content and processing parameters, such as injection pressure, injection speed, melt temperature, and mold temperature, on the interfacial adhesion were investigated experimentally. The results of the interfacial adhesion characterized by lap shear measurement showed that the interfacial temperature and heat transfer between PE and PA6 interfaces play a very significant role in the bonding process. The fracture surfaces of the specimens prepared at different calculated interfacial temperature were investigated by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), which suggested that the fracture failure changes from adhesive to cohesive failure with increasing interfacial temperature. The contribution of crystalline parts of the in situ formed copolymers to the enhancement in interfacial adhesion also was determined by DSC analysis. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1112–1124, 2009
Physical and psychological impairments of women with upper limb lymphedema following breast cancer treatment
Authors: Chachaj Angelika , Małyszczak Krzysztof , Pyszel Krystian , Lukas Joanna , Tarkowski Radosław , Pudełko Marek , Andrzejak Ryszard , Szuba Andrzej
Published: April 2009

Objective: The aim of the study was to identify factors associated with worse physical and emotional functioning of breast cancer survivors with upper extremity lymphedema.

Methods: 1250 sets of questionnaires consisting of WHO‐DAS II, EORTC QLQ‐C30, EORTC QLQ‐BR23 and GHQ‐30 were mailed to women who underwent a breast cancer surgery at the Lower Silesian Oncology Center in Poland between January 1998 and December 2005.

Results and conclusions: The response rate was 33.47%. 117 women were included into a lymphedema group and 211 into a group without this complication. Women with lymphedema were more disabled (overall disability (DAS) score 39.78 versus 34.67; p<0.001), reported symptoms from the upper extremity (shoulder or arm pain and difficulties in arm movement) and from the operated breast (pain and swelling) 2–3 times more often, experienced poorer quality of life (global quality of life (QOL) score 0.50 versus 0.57; p=0.005) and higher psychological distress (GHQ score 10.61 versus 8.01; p=0.007) in comparison to breast cancer survivors without lymphedema. The factors associated with higher DAS score, higher GHQ score and lower QOL score in women with lymphedema were as following: pain in the upper limb (mainly shoulder and arm), pain in operated breast, difficulties with arm movement, localization of lymphedema within the hand or in operated breast, a history of dermatolymphangitis and of receiving chemotherapy. Severity of lymphedema, younger age, BMI and localization of lymphedema within the dominant limb were not considerably related to worse outcomes in these women. Copyright © 2009 John Wiley & Sons, Ltd.
Quality of life of family caregivers at 2 years after a relative's cancer diagnosis
Authors: Kim Youngmee , Spillers Rachel L.
Published: April 2009

Purpose: Although a growing body of research has documented the quality of life (QOL) of cancer survivors beyond the initial phase of the survivorship, similar knowledge about family caregivers of cancer survivors remains limited. Thus, the current study aimed: (a) to characterize the multidimensional aspects of the QOL of family caregivers of cancer survivors at 2 years after the diagnosis and (b) to predict certain aspects of caregivers' QOL by their demographic and caregiving characteristics.

Methods: A total of 1635 caregivers of cancer survivors participated in the nationwide Quality of Life Survey for Caregivers. Multidimensional aspects of QOL were assessed, including mental and physical health, as well as psychological adjustment and spirituality at 2 years post‐diagnosis of their relatives' cancer.

Results: Family caregivers reported normal levels of QOL after 2 years post‐diagnosis, except that they were more likely to experience increased awareness of spirituality than do individuals who personally experience a chronic illness. In addition, caregivers' age and income and care‐recipients' poor mental and physical functioning were significant predictors of their QOL at 2 years post‐diagnosis.

Conclusions: The findings suggest that younger, relatively poor caregivers who are providing care to relatives with poor mental and physical functioning may benefit from interventions to help in their spirituality and psychological and physical adjustment, 2 years after the initial cancer diagnosis. In addition, older, relatively poor caregivers may benefit from programs to reduce the physical burden of caregiving. These findings have implications for advancing public health research and practice. Copyright © 2009 John Wiley & Sons, Ltd.
Botulinum Toxin Type A Inhibits the Growth of LNCaP Human Prostate Cancer Cells In Vitro and In Vivo
Authors: Karsenty Gilles , Rocha Joice , Chevalier Simone , Scarlata Eleonora , Andrieu Claudia , Zouanat Fatima Z. , Rocchi Palma , Giusiano Sophie , Elzayat Ehab A. , Corcos Jacques
Published: April 2009

INTRODUCTION AND OBJECTIVE

Botulinum toxin type A (BTA) intraprostatic injection induces an improvement of urinary symptoms related to benign prostatic hypertrophy (BPH). Infra‐clinical prostate cancer (PCa) foci and pre‐neoplasic lesions occur concomitantly with BPH in a significant number of patients. The objective of this study was to address whether BTA influences the growth of prostate tumors.

METHODS

Proliferation of PC‐3 and LNCaP cell lines exposed or not to BTA (Botox) was assessed and compared. Presence of synaptic vesicle 2 (SV2) protein, the membrane receptor of BTA, was studied in both cell lines. After nude mice bearing LNCaP xenografts received intra‐tumoral BTA or saline injection, tumor volume, serum PSA, histopathology and detection of apoptosis were comparatively assessed.

RESULTS

BTA significantly reduced LNCaP cell proliferation and increased apoptosis in a dose‐dependent manner but did not affect PC‐3. The SV2 receptor was present in both cell lines at a ratio of 4:1 (LNCaP/PC‐3). One unit of BTA resulted in a significantly lower growth rate and slower PSA progression over 28 days compare to controls. The tumors were morphologically similar. There were significantly more apoptotic cells compared to controls.

CONCLUSION

BTA inhibits the growth of LNCaP human PCa cells in vitro and in vivo. These findings indicate that intra‐prostatic BTA injections to treat BPH are unlikely to promote the growth of co‐existing infra‐clinical PCa foci in men. A potential inhibitory effect of BTA on the growth of human PCa should be further studied. Prostate 69:1143–1150, 2009. © 2009 Wiley‐Liss, Inc.
Detection of interactions of the β‐amyloid peptide with small molecules employing transferred NOEs
Authors: Benaki Dimitra , Stathopoulou Konstantina , Leondiadis Leondios , Ferderigos Nikolaos , Pelecanou Maria , Mikros Emmanuel
Published: April 2009

The interaction of pineal hormone melatonin, the histological dye thioflavin T, and the olive tree polyphenol oleuropein, with the 28 amino acid residue N‐terminal fragment of the β‐amyloid peptide (β‐AP) of Alzheimer's disease, [β‐AP(1‐28)], was detected in solution through the observation of transferred NOEs (trNOEs) in 1D and 2D NOE spectroscopy (NOESY) experiments. The trNOE method is applied for the first time in the detection of interactions of soluble β‐AP(1‐28) with small molecules and may provide a means of screening for the identification of possible inhibitors of the formation of neurotoxic β‐AP assemblies. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Insulator–semiconductor–metallic state transition induced by electric fields in Mn‐doped NaNbO3
Authors: Molak Andrzej , Szot Krzysztof
Published: April 2009

The electro‐forming procedure was applied to NaNbO3:Mn and NaNbO3 insulator crystals. The electric current flow induced a transition to the metallic‐type temperature dependence of the resistance. The Mn dopant shortened the time needed for the transition. The LC‐AFM measurement showed a non‐homogeneous distribution in local resistance resulting from the electric field via the AFM tip. We ascribe this effect to percolation in the network of the highly conducting filaments, whose formation is facilitated by the Mn ions. We conclude that the insulator–metal transition is induced within a subsystem of extended defects already existing in the NaNbO3:Mn crystal lattice host. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantification of hepcidin using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Bansal Sukhvinder S. , Halket John M. , Fusova Jane , Bomford Adrian , Simpson Robert J. , Vasavda Nisha , Thein Swee Lay , Hider Robert C.
Published: April 2009

Hepcidin is known to be a key systemic iron‐regulatory hormone which has been demonstrated to be associated with a number of iron disorders. Hepcidin concentrations are increased in inflammation and suppressed in hemochromatosis. In view of the role of hepcidin in disease, its potential as a diagnostic tool in a clinical setting is evident. This study describes the development of a matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) assay for the quantitative determination of hepcidin concentrations in clinical samples. A stable isotope labeled hepcidin was prepared as an internal standard and a standard quantity was added to urine samples. Extraction was performed with weak cation‐exchange magnetic nanoparticles. The basic peptides were eluted from the magnetic nanoparticles using a matrix solution directly onto a target plate and analyzed by MALDI‐TOF MS to determine the concentration of hepcidin. The assay was validated in charcoal stripped urine, and good recovery (70–80%) was obtained, as were limit of quantitation data (5 nmol/L), accuracy (RE <10%), precision (CV <21%), within ‐day repeatability (CV <13%) and between‐day repeatability (CV <21%). Urine hepcidin levels were 10 nmol/mmol creatinine in healthy controls, with reduced levels in hereditary hemochromatosis (P < 0.000005) and elevated levels in inflammation (P < 0.0007). In summary a validated method has been developed for the determination of hepcidin concentrations in clinical samples. Copyright © 2009 John Wiley & Sons, Ltd.
Structural studies on Helicobacter pylori 3‐deoxy‐D‐manno‐2‐octulosonate‐8‐phosphate synthase using electrospray ionization mass spectrometry: a tetrameric complex composed of dimeric dimers
Authors: Li Zhili , Sau Apurba Kumar
Published: April 2009

Helicobacter pylori 3‐deoxy‐D‐manno‐2‐octulosonate‐8‐phosphate (KDO8P) synthase catalyzes the conversion of D‐arabinose‐5‐phosphate (A5P) and phosphoenolpyruvate (PEP) to produce KDO8P and inorganic phosphate. Since this protein is absent in mammals, it might therefore be an attractive target for the development of new antibiotics. Unlike E. coli KDO8P synthase (class I), the H. pylori counterpart is a class II enzyme, where it requires a divalent transition metal ion for catalysis. Although the metal ions have been shown to be important for catalysis, their role in the structure is not understood. Using electrospray ionization mass spectrometry (ESI‐MS), the role of the metal ions in H. pylori KDO8P synthase has been investigated. This protein is found to be a tetramer in the gas phase but dissociates into the dimer with increasing declustering potential (DP2) suggesting an existence of a ‘structurally specific’ tetramer. An examination of mass spectra revealed that the tetrameric state of the Cd2+‐reconstituted enzyme is less stable than those of the Zn2+‐, Co2+‐ and Cu2+‐enzymes. The stoichiometry of metal binding to the protein depends on the nature of the metal ion. Taken together, our data suggest that divalent metal ions play an important role in the quaternary structure of the protein and the tetrameric state may be primarily responsible for catalysis. This study demonstrates the first structural characterization and stoichiometry of metal binding in class II KDO8P synthase using electrospray ionization quadrupole time‐of‐flight mass spectrometry under nondenaturing conditions. Copyright © 2009 John Wiley & Sons, Ltd.
Learning to teach elementary school science as argument
Authors: Zembal‐Saul Carla
Published: April 2009

New views of proficiency in K‐8 science that highlight the importance of engaging children in the discourses and practices of science have raised the stakes for elementary teachers and the teacher educators who prepare them. In this paper, a framework for teaching science as argument is presented. The framework is advanced as a means of addressing problems of practices faced by preservice teachers, creating coherence for the design of teacher education experiences, and serving as a tool for shaping a design‐based research agenda. Findings of three research studies that examined preservice teachers' developing understandings and practices for teaching science as argument and the ways in which teacher education experiences mediated learning are synthesized. Across the studies, findings suggest that the framework serves as a powerful scaffold for preservice teachers' developing thinking and practice. More specifically, early attention to evidence and argument can leverage other important aspects of effective science teaching, such as attention to classroom discourse and the role of the teacher in monitoring and assessing children's thinking. In closing, a case is made for coherence among science learning opportunities, learning to teach science experiences, and field experiences. © 2009 Wiley Periodicals, Inc. Sci Ed 93:687–719, 2009
Incident angle and energy dependences of low‐energy Ar+ ion sputtering of GaAs/AlAs multilayered system
Authors: Nagatomi T. , Bungo T. , Takai Y.
Published: April 2009

Dependences of the depth resolution in Auger electron spectroscopy sputter‐depth profiling of a GaAs/AlAs superlattice reference material on the incident angle and energy of primary Ar+ ions were investigated. The results revealed that the depth resolution is improved for the lower primary energy as a square root of the primary energy of ions at both the incident angles of 50° and 70° , except for 100 eV at 50° , where the significant deterioration of the depth resolution is induced by the preferential sputtering of As in AlAs, and the difference in the etching rate between GaAs and AlAs. The deterioration of the depth resolution, i.e. the difference in the etching rate and the preferential sputtering, observed for 100 eV at 50° was suppressed by changing the incident angle of ions from 50° to 70° , resulting in the high‐depth resolution of ∼1.3 nm. The present results revealed that the glancing incidence of primary ions is effective to not only reducing the atomic mixing but also suppressing the difference in the etching rates between GaAs and AlAs and the preferential sputtering in the GaAs/AlAs multilayered system. The results also suggest that careful attention is required for the optimization of conditions of sputter‐depth profiling using GaAs/AlAs superlattice materials under low‐energy ion irradiation. Copyright © 2009 John Wiley & Sons, Ltd.
Addressing between‐study heterogeneity and inconsistency in mixed treatment comparisons: Application to stroke prevention treatments in individuals with non‐rheumatic atrial fibrillation
Authors: Cooper Nicola J. , Sutton Alex J. , Morris Danielle , Ades A. E. , Welton Nicky J.
Published: April 2009

Mixed treatment comparison models extend meta‐analysis methods to enable comparisons to be made between all relevant comparators in the clinical area of interest. In such modelling it is imperative that potential sources of variability are explored to explain both heterogeneity (variation in treatment effects between trials within pairwise contrasts) and inconsistency (variation in treatment effects between pairwise contrasts) to ensure the validity of the analysis.

The objective of this paper is to extend the mixed treatment comparison framework to allow for the incorporation of study‐level covariates in an attempt to explain between‐study heterogeneity and reduce inconsistency. Three possible model specifications assuming different assumptions are described and applied to a 17‐treatment network for stroke prevention treatments in individuals with non‐rheumatic atrial fibrillation.

The paper demonstrates the feasibility of incorporating covariates within a mixed treatment comparison framework and using model fit statistics to choose between alternative model specifications. Although such an approach may adjust for inconsistencies in networks, as for standard meta‐regression, the analysis will suffer from low power if the number of trials is small compared with the number of treatment comparators. Copyright © 2009 John Wiley & Sons, Ltd.
Stock market reaction to CEO certification: the signaling role of CEO background
Authors: Zhang Yan , Wiersema Margarethe F.
Published: April 2009

As a direct result of the corporate scandals that started with Enron and led to general unrest in the financial markets, the Securities and Exchange Commission required chief executive officers (CEOs) and chief financial officers of large publicly traded companies to certify their financial statements. Using market signaling theory, we propose that attributes of the CEO send important signals to the investment community as to the credibility of the CEO certification and thus the quality of the firm's financial statements, which in turn impact the stock market reaction to the CEO certification. We find that a CEO's shareholdings and external directorships are positively related to the abnormal returns of CEO certification. Further, the stock market penalizes a firm with a CEO who is associated with the firm's prior financial restatement and rewards a firm with a CEO who is appointed after the firm's prior financial restatement. Copyright © 2009 John Wiley & Sons, Ltd.
Metal‐exchanged clay and zeolite additives as smoke suppressants and fire retardants for poly(vinyl chloride)
Authors: Zestos Alexander G. , Grinnell Cole L. , Vinh Long J. , Pike Robert D. , Starnes William H.
Published: April 2009

Cone calorimetry studies showed that various metal‐exchanged clays and zeolites containing only 3–4% of Cu(II), Cu(I), Zn(II), or Al(III) were effective smoke suppressants and fire retardants for plasticized poly(vinyl chloride). Copper(II)‐Zn(II) and Cu(II)‐Al(III) synergism for smoke and heat reduction was observed with binary blends of the clays, and the effectiveness of the additives was usually improved considerably by heating plasticizer‐additive mixtures under very high shear before combining them with the polymer. Possible mechanisms of action of the additives are described. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Preparation and characterization of PVC/montmorillonite nanocomposites—A review
Authors: Pagacz Joanna , Pielichowski Krzysztof
Published: April 2009

This article presents an overview of the preparation and characterization of poly(vinyl chloride)/montmorillonite (PVC/MMT) nanocomposites. Different methods of PVC/MMT nanocomposite preparation are discussed. The incorporation of MMT into the PVC matrix results in an increase of thermal stability and induces changes in the mechanical properties. However, the properties of PVC/MMT nanocomposites depend strongly on the MMT organic modification procedure that governs the extent of MMT penetration by PVC macrochains and plays an important role with regard to the morphology formation. Flammability as well as other properties—barrier, optical, etc.—of PVC/MMT nanomaterials are also described. Finally, a future outlook is given. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
Uncommon Compounds in Antimony Pentachloride – Ionic Liquid Systems: Synthesis, Crystal Structure and Vibrational Spectra of the Complexes [TPT][SbCl6] and [Cl‐EMIm][SbCl6]
Authors: Gjikaj Mimoza , Xie Tao , Brockner Wolfgang
Published: April 2009

Single crystals of 2,3,5‐triphenyltetrazolium hexachloroantimonate(V), [TPT][SbCl6] (1) and of 1‐ethyl‐3‐methyl‐4‐chloroimidazolium hexachloroantimonate(V), [Cl‐EMIm][SbCl6] (2) could be obtained and their crystal structures determined. Compound 1 crystallizes in the monoclinic space group P21/c (C2h5) with a = 1328.7(2), b = 1085.2(1), c = 1752.4(3) pm, β = 111.51(1)°, and Z = 4, whereas compound 2 crystallizes in the same monoclinic space group P21/c (C2h5) with a = 716.9(1), b = 1378.0(3), c = 1589.5(2) pm, β = 97.61(1)°, and Z = 4. The compound 1 is composed of a pair of ions, the 2,3,5‐triphenyltetrazolium cation and the hexachloroantimonate(V) anion. 2 is an ionic 1:1 compound with 1‐ethyl‐3‐methyl‐4‐chloroimidazolium cations, formed by chlorination of [EMIm]+ by SbCl5 and hexachloroantimonate(V) anions. The FT‐Raman spectra of the title compounds have been recorded and interpreted, especially with respect to the inorganic part respective to the [SbCl6]–.
Synthesis, Structure, and Reactivity of Pentacoordinate Hydrosilanes Bearing a 2‐(Phenylazo)phenyl Group
Authors: Yamamura Masaki , Kano Naokazu , Kawashima Takayuki
Published: April 2009

Coordination states of trihydrosilane (E)‐1, chlorodihydrosilane (E)‐2, and tetrahydrodisiloxane (E,E)‐4 bearing 2‐(phenylazo)phenyl groups were revealed by X‐ray crystallographic analysis and NMR spectroscopy. Trihydrosilane (E)‐1 with a tetracoordinate silicon showed higher reactivity with CuCl2 than trihydrophenylsilane. Photoirradiation of (E)‐2 and (E,E)‐4, which have pentacoordinate silicon atom(s), successfully gave the corresponding (Z)‐isomers. Each reaction of trihydrosilane (E)‐1 and tetrahydrodisiloxane (E,E)‐4 with fluoride ion gave 1,2‐diphenylhydrazine through an intramolecular hydrosilylation.
Feedback in laparoscopic skills acquisition: an observational study during a basic skills training course
Authors: Schaafsma B. E. , Hiemstra E. , Dankelman J. , Jansen F. W.
Published: April 2009

This study aimed to obtain insight in the effect of expert feedback during a basic laparoscopic skills training course for residents. A questionnaire was held among participants regarding provided feedback and the self-perceived laparoscopic skills improvement. The participants (n = 24) who completed the questionnaire were in their first to fifth postgraduate year. Most feedback was directed at intracorporeal knot tying (47% reported extensive feedback), while camera navigation and body positioning received the least feedback (40% and 43%, respectively, responded to have received no feedback at all). After the course, the self-perceived competence in intracorporeal knot tying and cutting had improved significantly, while camera navigation, body positioning, pointing, and grasping tasks did not improve. In conclusion, most benefit from expert feedback can be obtained at the start of the learning curve. Therefore, the basic laparoscopic skills course should be attended early in residency. Additionally, it is crucial that training objectives are clear prior to a course for both the expert and the trainee, in order to focus the feedback on all training objectives.
Management and outcome in 75 individuals with long‐chain fatty acid oxidation defects: results from a workshop
Authors: Spiekerkoetter U. , Lindner M. , Santer R. , Grotzke M. , Baumgartner M. R. , Boehles H. , Das A. , Haase C. , Hennermann J. B. , Karall D. , de Klerk H. , Knerr I. , Koch H. G. , Plecko B. , Röschinger W. , Schwab K. O. , Scheible D. , Wijburg F. A. , Zschocke J. , Mayatepek E. , Wendel U.
Published: April 2009

At present, long‐chain fatty acid oxidation (FAO) defects are diagnosed in a number of countries by newborn screening using tandem mass spectrometry. In the majority of cases #Affected newborns are asymptomatic at time of diagnosis and acute clinical presentations can be avoided by early preventive measures. Because evidence‐based studies on management of long‐chain FAO defects are lacking, we carried out a retrospective analysis of 75 patients from 18 metabolic centres in Germany, Switzerland, Austria and the Netherlands with special regard to treatment and disease outcome. Dietary treatment is effective in many patients and can prevent acute metabolic derangements and prevent or reverse severe long‐term complications such as cardiomyopathy. However, 38% of patients with very long‐chain acyl‐CoA dehydrogenase (VLCAD) deficiency had intermittent muscle weakness and pain despite adhering to therapy. Seventy‐six per cent of patients with disorders of the mitochondrial trifunctional protein (TFP)‐complex including long‐chain 3‐hydroxyacyl‐CoA dehydrogenase (LCHAD) deficiency, had long‐term myopathic symptoms. Of these, 21% had irreversible peripheral neuropathy and 43% had retinopathy. The main principle of treatment was a fat‐reduced and fat‐modified diet. Fat restriction differed among patients with different enzyme defects and was strictest in disorders of the TFP‐complex. Patients with a medium‐chain fat‐based diet received supplementation of essential long‐chain fatty acids. l‐Carnitine was supplemented in about half of the patients, but in none of the patients with VLCAD deficiency identified by newborn screening. In summary, in this cohort the treatment regimen was adapted to the severity of the underlying enzyme defect and thus differed among the group of long‐chain FAO defects.
Comparison of molecular fingerprinting methods for analysis of soil microbial community structure
Authors: Okubo Atsushi , Sugiyama Shu‐ichi
Published: April 2009

Denaturing gradient gel electrophoresis (DGGE), terminal‐restriction fragment length polymorphism (T‐RFLP) analysis, and automated ribosomal intergenic spacer analysis (ARISA) have been widely used as molecular fingerprinting methods for analysis of microbial communities. To find suitable methods, we compared the three fingerprinting methods by analyzing soil fungal communities in four differing land‐use types: bare ground, crop fields, grasslands, and forests. We also examined optimal primer pairs for DGGE analysis by comparing single and mixed DNA samples of cultured fungal populations. Principal coordinate analysis (PCO), nonmetric multidimensional scaling method (NMDS), and analysis of similarities (ANOSIM), which are major multivariate statistical analyses for quantifying fingerprint patterns, were compared. All three fingerprinting methods yielded clear discrimination of soil fungal communities among the four land‐use types, irrespective of statistical methods. The advantages and disadvantages of the three fingerprinting methods were discussed.
Accelerated soil CO2 efflux after conversion from secondary oak forest to pine plantation in southeastern China
Authors: Shi Zheng , Li Yiqing , Wang Shaojun , Wang Guobing , Ruan Honghua , He Rong , Tang Yanfei , Zhang Zengxin
Published: April 2009

Soil respiration (Rs) is an important component of the carbon cycle in terrestrial ecosystems, and changes in soil respiration with land cover alteration can have important implications for regional carbon balances. In southeastern China (Xiashu Experimental Forest, Jiangsu Province), we used an automated LI‐8100 soil CO2 flux system to quantify diurnal variation of soil respiration in a secondary oak forest and a pine plantation. We found that soil respiration in the pine plantation was significantly higher than that in the secondary oak forest. There were similar patterns of soil respiration throughout the day in both the secondary oak forest and the pine plantation during our 7‐month study (March–September 2005). The maximum of Rs occurred between 4:00 pm and 7:00 pm. The diurnal variations of Rs were usually out of phase with soil surface (0.5 cm) temperature (Tg). However, annual variation in Rs correlated with surface soil temperature. Soil respiration reached to a maximum in June, and decreased thereafter. The Q10 of Rs in the secondary oak forest was significantly higher than that in the pine plantation. The higher Q10 value in the secondary oak forest implied that it might release more CO2 than the pine plantation under a global‐warming scenario. Our results indicated that land‐use change from secondary forest to plantation may cause a significant increase in CO2 emission, and reduce the temperature sensitivity of soil respiration in southeastern China.
Reconstructing the Rheumatoid Wrist: A Utility Analysis Comparing Total Wrist Fusion and Total Wrist Arthroplasty from the Perspectives of Rheumatologists and Hand Surgeons
Authors: Cavaliere Christi M. , Oppenheimer Adam J. , Chung Kevin C.
Published: April 2009

Rheumatologists and hand surgeons have historically demonstrated strikingly divergent attitudes toward the benefits of surgical intervention, either total wrist fusion or total wrist arthroplasty, for the rheumatoid wrist. A utility analysis was conducted to compare a national random sample of hand surgeons and rheumatologists regarding their opinions about surgical management of severe rheumatoid wrist disease. A web-based trade-off utility survey was developed, and participants were presented with survey scenarios comparing well-controlled rheumatoid arthritis with operative and non-operative management. Utility values were calculated for each scenario, and a decision analytic model was constructed. Utility values for rheumatologists and hand surgeons did not differ significantly for any scenario. Total wrist arthroplasty was associated with the highest expected gain in quality-adjusted life-years for each subgroup. This decision analytic model demonstrates similar opinions between two subspecialties that have historically demonstrated divergent attitudes towards rheumatoid hand surgery.
Type IV FDP Avulsion: Lessons Learned Clinically and through Review of the Literature
Authors: Henry Steven L. , Katz Mark A. , Green David P.
Published: April 2009

The type IV flexor digitorum profundus avulsion is a rare injury involving fracture of the volar base of the distal phalanx and separation of the tendon from the fracture fragment. Recommendations for management are sparse and are substantiated only by a few isolated case reports. We recently encountered two of these injuries, both of which proved challenging, particularly with regard to joint incongruity and tendon adhesions. In reviewing the literature, it is apparent that no consensus exists regarding surgical strategies. However, based on our experience and that of other authors, we can suggest the following: (1) high index of suspicion of this potentially deceptive injury, with use of magnetic resonance imaging or ultrasound if preoperative confirmation is needed; (2) rigid bony fixation that prevents dorsal subluxation of the distal phalanx; (3) tendon repair that is independent of the bony fixation; and (4) early range of motion therapy.
Color Measurements in Blue‐Tinted Cups for Virgin‐Olive‐Oil Tasting
Authors: Melgosa M. , Gómez‐Robledo L. , Huertas R. , Capitán‐Vallvey L. F. , Moyano M. J. , Heredia F. J.
Published: April 2009

Color measurements have been performed using eighteen virgin‐olive‐oil tasting cups with ten different commercial virgin olive oils, positioned in a color cabinet with a D65 source. Three geometries (spectroradiometer tilted 0°, 30°, and 60°) were employed, simulating different positions of the taster’s eye. Our main goal was to test whether traditional blue‐tinted cups effectively conceal the color of virgin olive oils, as desired in sensorial analyses. None of the cups employed had all their geometrical dimensions within the standardized values, despite being cups used in official sensorial analyses. Measuring a magnitude similar to the spectral transmittance, we found substantial differences among the glasses of the eighteen tasting cups. Comparing color variability for one virgin olive oil in different tasting cups, and one tasting cup with different virgin olive oils, we discovered that: (1) variability was higher in the case of one virgin olive oil in different cups; (2) in both cases the variability increased with the tilt of the spectroradiometer; (3) even when the variability was lowest (i.e., 0° measurements for two oils in the same cup), the average color difference was above typical visual thresholds in simultaneous comparison experiments. In the most usual case of a successive comparison between two oils in the same tasting cup, it is expected that in most cases tasters will perceive color differences between the oils when their eyes are tilted 60° with respect to the horizontal, but not when they observe the cup in the horizontal direction. In summary, blue‐tinted olive‐oil‐tasting cups reduce, but do not completely conceal, oil color. The use of opaque tasting cups with black walls is suggested.
Alternative splicing of CCN mRNAs …. it has been upon us
Authors: Perbal Bernard
Published: April 2009

Variant CCN proteins have been identified over the past decade in several normal and pathological situations. The production of CCN truncated proteins have been reported in the case of CCN2(ctgf), CCN3(nov), CCN4(wisp‐1) and CCN6(wisp‐3). Furthermore, the natural CCN5 is known to miss the C‐terminal domain that is present in all other members of the CCN family of proteins. In spite of compelling evidence that assign important biological activities to these truncated CCN variants, their potential regulatory functions have only recently begun to be widely accepted. The report of CCN1(cyr61) intron 3 retention in breast cancer cells now confirms that, in addition to well documented post‐translational processing of full length CCN proteins, alternative splicing is to be regarded as another effective way to generate CCN variants. These observations add to a previous bulk of evidence that support the existence of alternative splicing for other CCN genes. It has become clearly evident that we need to recognize these mechanisms as a means to increase the biological diversity of CCN proteins.
Compared effects of surgical and natural menopause on climacteric symptoms, osteoporosis, and metabolic syndrome
Authors: Özdemir Suna , Çelik Çetin , Görkemli Hüseyin , Kıyıcı Aysel , Kaya Buğra
Published: April 2009

Objective

To compare the effects of surgical (ie, earlier) and natural (ie, later) menopause on climacteric symptoms, osteoporosis, and metabolic syndrome.

Method

The study was conducted with 94 women who underwent hysterectomy and bilateral oophorectomy and 95 women who were older than 40 years and in natural menopause. None had received hormone theraphy or osteoporosis treatment. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III.

Results

The rates of hot flushes (P = 0.001), sweating (P = 0.001), poor memory (P = 0.04), change in sexual desire (P = 0.04), and osteoprosis (diagnosed in the hip bone, P = 0.005) were significantly higher among the women in surgical menopause, but the rate of metabolic syndrome was similar in the 2 groups (47.8% and 40%; P = 0.28).

Conclusion

Compared with natural menopause, surgical menopause was found to be associated with highter rates of climacteric symptoms and osteoporosis but not of of metabolic syndrome.
The Fernbank interglacial site near Ithaca, New York, USA
Authors: Karrow Paul F. , Bloom Arthur L. , Haas Jean Nicolas , Heiss Andreas G. , McAndrews John H. , Miller Barry B. , Morgan Alan V. , Seymour Kevin L.
Published: April 2009

The Fernbank interglacial site, on the west side of Cayuga Lake, New York, has been recently subjected to more detailed study. To a lengthened mollusc list are added ostracodes, insects, fish, pollen, and plant macrofossils. Of these, plants are well preserved and diverse, whereas other groups are poorly preserved and incomplete. Nevertheless, all support the interglacial assignment (Sangamon), which is further supported by minimum age radiocarbon dates (>50,000 14C yr BP) and a TL date of 81 ± 11 ka. In the plant record near the top of the sequence, abundant tree charcoal indicates forest fires. Like the Toronto interglacial record, the plants show a declining July mean temperature from 24 to 18°C (according to transfer functions) through the sequence, from mixed deciduous forest to boreal forest.
Increased bioavailability of hesperetin-7-glucoside compared with hesperidin results in more efficient prevention of bone loss in adult ovariectomised rats
Authors: Habauzit Véronique , Nielsen Inge-Lise , Gil-Izquierdo Angel , Trzeciakiewicz Anna , Morand Christine , Chee Winnie , Barron Denis , Lebecque Patrice , Davicco Marie-Jeanne , Williamson Gary , Offord Elizabeth , Coxam Véronique , Horcajada Marie-Noëlle
Published: April 2009

Hesperidin (Hp), a citrus flavonoid predominantly found in oranges, shows bone-sparing effects in ovariectomised (OVX) animals. In human subjects, the bioavailability of Hp can be improved by the removal of the rhamnose group to yield hesperetin-7-glucoside (H-7-glc). The aim of the present work was to test whether H-7-glc was more bioavailable and therefore more effective than Hp in the prevention of bone loss in the OVX rat. Adult 6-month-old female Wistar rats were sham operated or OVX, then pair fed for 90 d a casein-based diet supplemented or not with freeze-dried orange juice enriched with Hp or H-7-glc at two dose equivalents of the hesperetin aglycone (0·25 and 0·5 %). In the rats fed 0·5 %, a reduction in OVX-induced bone loss was observed regarding total bone mineral density (BMD):+7·0 % in OVX rats treated with Hp (HpOVX) and +6·6 % in OVX rats treated with H-7-glc (H-7-glcOVX)v.OVX controls (P < 0·05). In the rats fed 0·25 % hesperetin equivalents, the H-7-glcOVX group showed a 6·6 % improvement in total femoral BMDv.the OVX controls (P < 0·05), whereas the Hp diet had no effect at this dose. The BMD of rats fed 0·25 % H-7-glc was equal to that of those given 0·5 % Hp, but was not further increased at 0·5 % H-7-glc. Plasma hesperetin levels and relative urinary excretion were significantly enhanced in the H-7-glcv.Hp groups, and the metabolite profile showed the absence of eriodictyol metabolites and increased levels of hesperetin sulphates. Taken together, improved bioavailability of H-7-glc may explain the more efficient bone protection of this compound.
Attenuation of proteolysis and muscle wasting by curcumin c3 complex in MAC16 colon tumour-bearing mice
Authors: Siddiqui Rafat A. , Hassan Samira , Harvey Kevin A. , Rasool Tamkeen , Das Tapas , Mukerji Pradip , DeMichele Stephen
Published: April 2009

Muscle wasting or cachexia is caused by accelerated muscle protein breakdown via the ubiquitin–proteasome complex. We investigated the effect of curcumin c3 complex (curcumin c3) on attenuation of muscle proteolysis usingin vitroandin vivomodels. Ourin vitrodata indicate that curcumin c3 as low as 0·50 μg/ml was very effective in significantly inhibiting (30 %;P < 0·05) tyrosine release from human skeletal muscle cells, which reached a maximum level of inhibition of 60 % (P < 0·05) at 2·5 μg/ml. Curcumin c3 at 2·5 μg/ml also inhibited chymotrypsin-like 20S proteasome activity in these cells by 25 % (P < 0·05). Forin vivostudies, we induced progressive muscle wasting in mice by implanting the MAC16 colon tumour. Thein vivodata indicate that low doses of curcumin c3 (100 mg/kg body weight) was able to prevent weight loss in mice bearing MAC16 tumours whereas higher doses of curcumin c3 (250 mg/kg body weight) resulted in approximately 25 % (P < 0·05) weight gain as compared with the placebo-treated animals. Additionally, the effect of curcumin c3 on preventing and/or reversing cachexia was also evident by gains in the weight of the gastrocnemius muscle (30–58 %;P < 0·05) and with the increased size of the muscle fibres (30–65 %;P < 0·05). Furthermore, curcumin inhibited proteasome complex activity and variably reduced expression of muscle-specific ubiquitin ligases: atrogin-1/muscle atrophy F-box (MAFbx) and muscle RING finger 1 (MURF-1). In conclusion, oral curcumin c3 results in the prevention and reversal of weight loss. The data imply that curcumin c3 may be an effective adjuvant therapy against cachexia.
Dietary lipid level affects growth performance and nutrient utilisation of Senegalese sole (Solea senegalensis) juveniles
Authors: Borges Pedro , Oliveira Beatriz , Casal Susana , Dias Jorge , Conceição Luis , Valente Luísa M. P.
Published: April 2009

Over the last few years, several aspects of Senegalese sole (Solea senegalensis) culture have been developed and optimised but the dietary lipid level for optimal growth has never been determined. Hence, five isonitrogenous diets (56 % dietary protein) with increasing dietary lipid levels (4, 8, 12, 16 and 20 % DM) were fed to satiation to triplicate groups of twenty fish (mean initial weight 10 g). Fifteen tanks were randomly assigned one of the five diets. Feed was distributed using automatic feeders, and fish were fed over a 16-week period. At the end of the experiment the fish fed on diets containing the two lowest dietary lipid levels (4 and 8 %) showed a 3-fold body-weight increase with a significantly higher daily growth index than fish fed higher lipid levels (1·2v.0·8). Moreover, these fish displayed a significantly lower dry feed intake (12 g/kg per d) and feed conversion ratio (1·0) compared with fish fed higher lipids levels (16–19 g/kg per d; feed conversion ratio 2·0). Low dietary lipid levels ( < 12 %) significantly improved nutrient retention and gain and hence growth, without major effects on whole-body composition. Despite the slight alteration inn-3 PUFA muscle content in the fish fed low-fat-diets, this fish fed low dietary lipid still remains a richn-3 PUFA product and generally maintained its nutritional value. These results evidenced a low lipid tolerance of Senegalese sole juveniles and suggest a maximal dietary inclusion level of 8 % lipids for both optimal growth and nutrient utilisation without compromising flesh quality.
Epistemology and Possibility
Authors: Hanrahan Rebecca
Published: April 2009

Recently the discussion surrounding the conceivability thesis has been less about the link between conceivability and possibility per se and more about the requirements of a successful physicalist program. But before entering this debate it is necessary to consider whether conceivability provides us with evenprima faciejustification for our modal beliefs. I argue that two methods of conceiving—imagining that p and telling a story about p—can provide us with such justification, but only if certain requirements are met. To make these arguments, I consider those of Paul Tidman, whose position I use as a foil.