bluuebunny/crossref_metadata_2025 huggingface dataset:
Apropriação e mobilização de saberes na prática pedagógica: contribuição para a formação de professores
Authors: Zibetti Marli Lúcia Tonatto , Souza Marilene Proença Rebello de
Published: October 2007

Este artigo visa introduzir alguns elementos de reflexão no campo da formação de professores, tomando por base a temática dos saberes docentes em torno da qual tem sido produzido um grande número de pesquisas nos últimos vinte anos. O eixo central da discussão encontra-se na busca de um modelo de formação docente centrado na racionalidade prática, permitindo conhecer de que forma os professores transformam em prática pedagógica as diferentes experiências formativas vividas ao longo da carreira profissional. Conhecer de que forma os saberes docentes são apropriados, modificados e mobilizados na prática pedagógica pode contribuir para a construção de propostas formativas que considerem esses saberes e a sua constituição como o ponto de partida dos projetos de formação, valorizando os professores como produtores de saberes. Para tanto, realizamos uma pesquisa de abordagem etnográfica que se desenvolveu durante um ano e meio com uma professora alfabetizadora, visando compreender o processo de apropriação de saberes docentes à luz da teoria do cotidiano. A pesquisa evidencia pelo menos dois elementos fundamentais na constituição desses saberes docentes: a historicidade e a dialogicidade, resultados de um processo complexo de apropriação/objetivação e criação que ocorre no cruzamento entre a trajetória individual de cada professor e a história das práticas sociais e educativas.
Sensitivity of the Dual‐Probe Heat‐Pulse Method to Spatial Variations in Heat Capacity and Water Content
Authors: Knight John H. , Jin Wei , Kluitenberg Gerard J.
Published: October 2007

Dual‐probe heat‐pulse (DPHP) sensors are useful for measuring soil heat capacity (C) and water content (θ), yet little is known about their effective measurement volume. We have adapted previous work on well testing to investigate the spatial sensitivity of the DPHP method for measuring both C and θ. Spatial sensitivity functions were derived by using a perturbation expansion approach in which C and θ vary with position, but differ only slightly from their uniform values C0 and θ0, respectively. Because the dimensionless forms of these spatial sensitivity functions are identical, the spatial sensitivity of the DPHP method is the same for both C and θ measurements. The spatial sensitivity function is not radially symmetric about the heater probe. Instead, the locations of the temperature and heater probes are of equal importance in defining the spatial sensitivity. The spatial sensitivity is greatest in small areas immediately outside of the heater and temperature probes. Far from the sensor, contours of equal spatial sensitivity approach the shapes of a family of ellipses. For a sensor with a probe spacing of 6 mm, the boundary containing 99% of the total spatial sensitivity is closely approximated by an ellipse with area 168 mm2 and a major axis 15.6 mm in length. The spatial sensitivity for C is unaffected by the magnitude of the soil thermal properties near the sensor, as long as the thermal properties are uniform. Likewise, for θ measurements, the spatial sensitivity is independent of the value of θ near the sensor, as long as θ is uniform.
Quantification of Microbial Methane Oxidation in an Alpine Peat Bog
Authors: Urmann Karina , Gonzalez‐Gil Graciela , Schroth Martin H. , Zeyer Josef
Published: October 2007

Methane (CH4) is an important greenhouse gas that is produced in different subsurface environments. Its main biological sink, microbial CH4 oxidation, can be quantified in situ in the vadose zone using gas push‐pull tests (GPPTs). This field method is based on the comparison of breakthrough curves of the reactant CH4 and a nonreactive tracer. Under diffusion‐dominated transport conditions, previously employed noble gases are unsuitable as tracers to calculate rate constants for CH4 oxidation due to differing diffusion coefficients. Here, we show that by performing two consecutive GPPTs and coinjecting acetylene (C2H2) as an inhibitor of CH4 oxidation in the second test, the reactant CH4 can be used as a substitute tracer. Applying this procedure, apparent first‐order rate constants for CH4 oxidation ranging from 0.38 to 0.82 h−1 were obtained in the vadose zone of three hummocks in an alpine peat bog near Lucerne, Switzerland. Corresponding estimates of in situ rates ranged from 4 to 299 ng CH4 g dry weight−1 h−1 In all but one GPPT, strong stable carbon isotope fractionation due to diffusion masked isotope fractionation due to microbial oxidation. Therefore, stable carbon isotope fractionation is suitable only to a limited extent as an indicator of microbial CH4 oxidation during a GPPT with diffusion‐dominated gas transport. In contrast, the presented procedure for the quantification of microbial CH4 oxidation using GPPTs can be applied without restrictions even in systems with high porosity. Furthermore, the presented method may be useful for quantifying other processes for which suitable inhibitors but no suitable tracers are available.
Outcomes, utilization, and costs among thalassemia and sickle cell disease patients receiving deferoxamine therapy in the United States
Authors: Delea Thomas E. , Hagiwara May , Thomas Simu K. , Baladi Jean‐Francois , Phatak Pradyumna D. , Coates Thomas D.
Published: October 2007

Deferoxamine mesylate (DFO) reduces morbidity and mortality associated with transfusional iron overload. Data on the utilization and costs of care among U.S. patients receiving DFO in typical clinical practice are limited however. This was a retrospective study using a large U.S. health insurance claims database spanning 1/97–12/04 and representing 40 million members in >70 health plans. Study subjects (n = 145 total, 106 sickle cell disease [SCD], 39 thalassemia) included members with a diagnosis of thalassemia or SCD, one or more transfusions (whole blood or red blood cells), and one or more claims for DFO. Mean transfusion episodes were 12 per year. Estimated mean DFO use was 307 g/year. Central venous access devices were required by 20% of patients. Cardiac disease was observed in 16% of patients. Mean total medical costs were $59,233 per year including $10,899 for DFO and $8,722 for administration of chelation therapy. In multivariate analyses, potential complications of iron overload were associated with significantly higher medical care costs. In typical clinical practice, use of DFO in patients with thalassemia and SCD receiving transfusions is low. Administration costs represent a large proportion of the cost of chelation therapy. Potential complications of iron overload are associated with increased costs. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Phase behavior on the binary and ternary mixtures of poly(isooctyl acrylate) + supercritical fluid solvents + isooctyl acrylate and CO2 + isooctyl acrylate system
Authors: Byun Hun‐Soo , Park Young‐Jin , Lim Jong‐Sung
Published: October 2007

Experimental cloud‐point data to the temperature of 180 °C and the pressure up to 2000 bar are presented for ternary mixtures of poly(isooctyl acrylate) + supercritical fluid solvents + isooctyl acrylate systems. Cloud‐point pressures of poly(isooctyl acrylate) + CO2 + isooctyl acrylate system is measured in the temperature range of 60–180°C and to pressures as high as 2000 bar with isooctyl acrylate concentration of 0–44.5 wt. This system changes the pressure–temperature slope of the phase behavior curves from upper critical solution temperature (UCST) region to lower critical solution temperature (LCST) region as the isooctyl acrylate concentration increases. Poly(isooctyl acrylate) does dissolve in pure CO2 to the temperature of 180°C and the pressure of 2000 bar. The phase behavior for poly(isooctyl acrylate) + CO2 + 9.5, 14.8, 30.6, and 41.9 wt % dimethyl ether (DME) mixture show the curve changes from UCST to LCST as the DME concentration increases. Also, the cloud‐point curves are measured for the binary mixtures of poly(isooctyl acrylate) in supercritical propane, propylene, butane, and 1‐butene. High pressure phase behaviors are measured for the CO2 + isooctyl acrylate system at 40, 60, 80, 100, and 120°C and pressure up to 200 bar. This system exhibits type‐I phase behavior with a continuous mixture‐critical curve. The experimental results for the CO2 + isooctyl acrylate system are modeled using the Peng‐Robinson equation of state. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Structure of polycondensates from hydroxymethylphenols
Authors: Christjanson Peep , Pehk Tõnis , Siimer Kadri , Paju Jane
Published: October 2007

The structure of oligomers obtained from mono‐hydroxymethylphenols in melt condensation at 120°C was determined using 13C NMR spectra in CD3OD solution. Alongside of methylene region of spectrum, valuable information was obtained from signals of aromatic carbons. Noncatalytic conditions promote the formation of dihydroxydibenzyl ethers in equilibrium with ortho‐ and para‐benzoquinones of oxymethylene derivatives. The final methylene linked oligomers are formed, mainly, by splitting the ether intermediates with free aromatic positions. In alkaline conditions, highly nucleophilic phenoxide ions of ortho‐hydroxymethyl compounds are responsible for substitution in free aromatic positions. The most favored reaction in the mixture of both hydroxymethylphenols is the formation of p,p′‐methylene. In condensation of para‐hydroxymethylphenol, formation of p,p′‐methylene groups occurs with simultaneous release of formaldehyde. High content of alkali stabilized ortho‐hydroxymethyl groups of fully substituted methylene linked oligomers determines the curing behavior of resol phenol–formaldehyde resins. The role of hemiformals in reactions was insignificant. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Dexamethasone alters sleep and fatigue in pediatric patients with acute lymphoblastic leukemia
Authors: Hinds Pamela S. , Hockenberry Marilyn J. , Gattuso Jami S. , Kumar Srivastava Deo , Tong Xin , Jones Heather , West Nancy , McCarthy Kathy S. , Sadeh Avi , Ash Monica , Fernandez Cheryl , Pui Ching‐Hon
Published: October 2007

BACKGROUND.

Dexamethasone improves the cure rate of childhood acute lymphoblastic leukemia (ALL) but causes physical and behavioral adverse events. The objective of the current study was to determine the effect of dexamethasone exposure on sleep and fatigue in pediatric patients with ALL.

METHODS.

One hundred pediatric patients with low‐risk or standard‐risk ALL were enrolled on 1 of 3 protocols (St. Jude Total XV, Children's Oncology Group [COG] 9904, or COG 9905) at 3 institutions. The mean age of the cohort was 9.24 ± 3.23 years (range, 5.03‐18.14 years). The majority of patients were white (79%) males (62%) with standard‐risk ALL (63%). The cohort was divided into 4 subgroups: St. Jude low‐risk, St. Jude standard‐risk, COG low‐risk, and COG standard‐risk. Patients wore a wrist actigraph to monitor sleep activity during 2 consecutive 5‐day periods: During the first period, they did not receive dexamethasone; and, during the second period, they did. Patients and their parents completed fatigue instruments on Days 2 and 5 of each period, and parents completed sleep diaries.

RESULTS.

Actual sleep minutes, sleep duration, total daily nap minutes, and fatigue increased significantly during the dexamethasone treatment for 3 to 4 of the subgroups. Total daily nap minutes increased significantly for both standard‐risk groups during the dexamethasone treatment. Parents reported significant increases in their child's nighttime awakenings, restless sleep, and nap time during dexamethasone treatment.

CONCLUSIONS.

Dexamethasone treatment during continuation therapy for childhood ALL significantly and adversely altered sleep and fatigue, confirming that sleep and fatigue are behavioral responses to dexamethasone. 2007. © 2007 American Cancer Society.
High circulating HER2 extracellular domain levels correlate with reduced efficacy of an aromatase inhibitor in hormone receptor‐positive metastatic breast cancer: A confirmatory prospective study
Authors: Colomer Ramon , Llombart‐Cussac Antonio , Lloveras Belen , Ramos Manuel , Mayordomo Jose I. , Fernández Roberto , Tusquets Ignasi , Gil Miguel , Barnadas Agustí , Constenla Manuel , Gilabert Montserrat , Alba Emilio
Published: October 2007

BACKGROUND.

In this specifically designed, prospective study, the authors addressed the predictive value of circulating levels of the extracellular domain (ECD) of HER2 in patients with metastatic breast cancer who were treated with letrozole.

METHODS.

Two hundred twenty‐six patients with hormone receptor‐positive, metastatic breast cancer received letrozole (2.5 mg daily) until they developed either disease progression or unacceptable toxicity. Efficacy was measured primarily as the time to progression (TTP) and, secondarily, as the objective response rate (ORR) and overall survival. HER2 ECD levels were determined by using a sandwich enzyme HER2/neu immunoassay before letrozole treatment was initiated. Positive HER2 ECD status was correlated with treatment efficacy.

RESULTS.

Forty‐two patients (19%) had elevated HER2 ECD levels, which were associated with primary tumor HER2 expression (P < .001) but not with age, performance status, location, or number of metastatic sites. The median TTP was significantly shorter among patients who had elevated HER2 ECD compared with the median TTP among patients who had normal levels (4 months vs 14 months; P = .0004), and the ORR was lower in the group with elevated HER2 ECD levels (14% vs 30%; P < .036). Overall survival was significantly shorter among patients with elevated serum HER‐2 ECD (P < .0005).

CONCLUSIONS.

Elevated HER2 ECD concentrations predicted poorer outcomes in postmenopausal women with metastatic hormone receptor‐positive breast cancer who were treated with aromatase inhibitors like letrozole. © 2007 American Cancer Society.
Differential expression of HNK‐1 and p75NTR in adult canine Schwann cells and olfactory ensheathing cells in situ but not in vitro
Authors: Bock Patricia , Beineke Andreas , Techangamsuwan Somporn , Baumgärtner Wolfgang , Wewetzer Konstantin
Published: October 2007

Olfactory ensheathing cells (OECs) are promising candidates for autologous cell transplantation therapies of nervous system injury and disease. Large animal models are relevant for transferring experimental data into clinical practice. In vivo studies have suggested that adult canine OECs may display similar regenerating capacities as their rodent counterpart. However, data on their molecular phenotype required for generating pure cell preparations are still scarce. In the present study, we comparatively analyzed expression of the carbohydrate HNK‐1 epitope and the neurotrophin receptor p75NTR in adult canine Schwann cells and olfactory ensheathing cells in situ and in vitro. Myelinating and nonmyelinating Schwann cells in situ exclusively expressed HNK‐1 and p75NTR, respectively, whereas OECs were negative for both markers. In vitro, OECs and Schwann cells shared cell surface expression of p75NTR but not of HNK‐1, which could be detected transiently in intracellular vesicles. This suggests that Schwann cells and OECs in vitro phagozytose HNK‐1+ cellular debris. The cultivation‐induced downregulation of HNK‐1 expression in Schwann cells and upregulation of p75NTR in OECs argues for the possibility that axonal signals control the expression of both markers in situ. Whereas HNK‐1 expression in Schwann cells is most likely controlled by signals inducing myelination, e.g., neuregulin, the mechanisms that may suppress p75NTR expression in OECs in situ remain to be elucidated. Interestingly, HNK‐1 expression in the adult dog was found in both sensory and motor nerve myelinating Schwann cells. This is reminiscent of humans and differs from rodents; it also underscores the importance of large animal models for translational research. J. Comp. Neurol. 505:572–585, 2007. © 2007 Wiley‐Liss, Inc.
Synthesis, Structure and a DFT/TDDFT Study of a Diimido‐Bridged Asymmetric Dimolybdenum Complex
Authors: Pal Kuntal , Sarkar Sabyasachi
Published: October 2007

The homobimetallic complex (Bu4N)2[MoO(mnt)Mo{o‐aminobenzothiolato(3–)‐N,S}2(mnt)] (2; mnt = 1,2‐dicyanoethylenedithiolate) has been synthesized as a dark green solid by treating (Bu4N)2[Mo2O4(mnt)2] (1) with o‐aminothiophenol in CH3CN. An X‐ray crystal structure analysis of 2 reveals that it possesses an asymmetric structure where one Mo has a distorted octahedral geometry and the other a square‐pyramidal geometry. The basal plane of the two Mo centers makes an angle of 26.41°, which is nearly one quarter of 90°. The shape of the ν(Mo=O) band in the IR spectrum of 2 suggests that these Mo atoms may have different oxidation states. The different reactivity of 1 with o‐aminothiophenol and 2‐aminoethanethiol was followed by EPR spectroscopy, and analysis of the different end‐products from these reactions supports the proposal that 2 is a mixed‐valence compound containing MoVI and MoIV centers. The electronic structures of 1 and 2 have been calculated at the DFT level of theory to analyse the effect of a deviation of the basal plane on the metal–metal bond in 2. The cyclic voltammetric responses of 1 and 2 have been measured to correlate the data with the computational results. TDDFT calculations have been performed on 1 and 2 in the gas phase and also in a solvent medium to assign the transitions corresponding to the peaks found in the respective experimental electronic absorption spectra of these complexes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Order imbalance and the dynamics of index and futures prices
Authors: Fung Joseph K.W. , Yu Philip L.H.
Published: October 2007

This study uses transaction records of index futures and index stocks, with bid/ask price quotes, to examine the impact of stock market order imbalance on the dynamic behavior of index futures and cash index prices. Spurious correlation in the index is purged by using an estimate of the “true” index with highly synchronous and active quotes of individual stocks. A smooth transition autoregressive error correction model is used to describe the nonlinear dynamics of the index and futures prices. Order imbalance in the cash stock market is found to affect significantly the error correction dynamics of index and futures prices. Order imbalance impedes error correction particularly when the market impact of order imbalance works against the error correction force of the cash index, explaining why real potential arbitrage opportunities may persist over time. Incorporating order imbalance in the framework significantly improves its explanatory power. The findings indicate that a stock market microstructure that allows a quick resolution of order imbalance promotes dynamic arbitrage efficiency between futures and underlying stocks. The results also suggest that the unloading of cash stocks by portfolio managers in a falling market situation aggravates the price decline and increases the real cost of hedging with futures. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:1129–1157, 2007
Transactions in futures markets: Informed or uninformed?
Authors: Frino Alex , Kruk Jennifer , Lepone Andrew
Published: October 2007

Using a proprietary data set from the Sydney Futures Exchange, this study reconciles an inconsistency in futures microstructure literature. One strand of the literature documents that single trades in futures markets contain information, whereas another strand finds that trade packages in futures markets do not contain information. This study controls for methodological and sample differences in examining the price impact of individual trades and trade packages. We find little evidence that transactions in futures markets contain information. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:1159–1174, 2007
Memory for spatial location and object‐place associations are differently processed by the hippocampal formation, parahippocampal areas TH/TF and perirhinal cortex
Authors: Bachevalier Jocelyne , Nemanic Sarah
Published: October 2007

To clarify the specific contribution of the medial temporal lobe structures in spatial memory, we tested monkeys (Macaca mulatta) with sham operations and with lesions of either the hippocampal formation, areas TH/TF or perirhinal cortex on two versions of the visual‐paired comparison task, measuring Spatial Location, and Object‐in‐Place associations. In the Spatial Location version, the comparison was between two identical objects presented simultaneously in a familiar and a novel location. In the Object‐in‐Place version, the comparison was between an image consisting of five objects and another image showing the same five objects, but with the position of 2, 3, or 4 of the objects rearranged. Finally, a VPC‐Control task was given to animals with hippocampal and perirhinal lesions, in which the comparison was between an image consisting of five objects and another image showing four of the five familiar objects and a new one. Perirhinal lesions yielded no deficit in the Spatial Location task and a deficit in the Object‐in‐Place task associated with a deficit in the VPC‐control task, suggesting that this cortical area does not participate in spatial memory unless the stimuli have overlapping features. Areas TH/TF lesions produced a deficit in both Spatial Location and Object‐in‐Place tasks, whereas the hippocampal lesions resulted in a deficit of Object‐in‐Place associations only. The data showed that the hippocampal formation, areas TH/TF, and perirhinal cortex appear to contribute interactively to object and spatial memory processes. © 2007 Wiley‐Liss, Inc.
Grid cell firing may arise from interference of theta frequency membrane potential oscillations in single neurons
Authors: Hasselmo Michael E. , Giocomo Lisa M. , Zilli Eric A.
Published: October 2007

Intracellular recording and computational modelling suggest that interactions of subthreshold membrane potential oscillation frequency in different dendritic branches of entorhinal cortex stellate cells could underlie the functional coding of continuous dimensions of space and time. Among other things, these interactions could underlie properties of grid cell field spacing. The relationship between experimental data on membrane potential oscillation frequency (f) and grid cell field spacing (G) indicates a constant scaling factor H = fG. This constant scaling factor between temporal oscillation frequency and spatial periodicity provides a starting constraint that is used to derive the model of Burgess et al. (Hippocampus, 2007). This model provides a consistent quantitative link between single cell physiological properties and properties of spiking units in awake behaving animals. Further properties and predictions of this model about single cell and network physiological properties are analyzed. In particular, the model makes quantitative predictions about the change in membrane potential, single cell oscillation frequency, and network oscillation frequency associated with speed of movement, about the independence of single cell properties from network theta rhythm oscillations, and about the effect of variations in initial oscillatory phase on the pattern of grid cell firing fields. These same mechanisms of subthreshold oscillations may play a more general role in memory function, by providing a method for learning arbitrary time intervals in memory sequences. © 2007 Wiley‐Liss, Inc.
Changes in mechanical properties of bone within the mandibular condyle with age
Authors: Huja Sarandeep S. , Rummel Andrew M. , Beck Frank M.
Published: October 2007

The purpose of the study was to compare indentation modulus (IM) and hardness of condylar bone in young and adult dogs. In addition we desired to examine histologic sections for bone formation activity in the two groups. Mandibular condyles were obtained from adult (1‐ to 2‐year‐old) and young (∼5‐m old) dogs. Two sections/condyle were obtained and one was processed for histomorphometry and the other for mechanical analyses. Indents were made on moist condylar trabecular bone to a depth of 500 nm at a loading rate of 10 nm/s using a custom‐made hydration system to obtain IM and hardness. Histomorphometric analyses measured the bone volume/total volume (BV/TV%) and ratio of labeled to unlabeled bone within the condyle. Data were analyzed using a repeated‐measures factorial analysis of variance and Tukey–Kramer method. Overall, the IM of the adult condyles (10.0 ± 3.4 GPa, Mean ± SD) were significantly (P < 0.0001) higher than in young dogs (5.6 ± 2.6 GPa). There was a greater bone mass in the young (60.2%) versus the adult condyles (42%). Also, significantly more labeled bone in the young (66.1%) condylar bone suggested higher bone forming activity than in adult condyles (27.5%). With age there is a change in mass and material properties in the trabecular bone of the mandibular condyle in dogs. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
The “pseudo‐craniovertebral articulation” in the deep‐sea fish Stomias boa (Teleostei: Stomiidae)
Authors: Schnell Nalani K. , Bernstein Peter , Maier Wolfgang
Published: October 2007

Many predatory deep‐sea fishes show highly specialized modifications of their feeding apparatus, e.g., elongate jaws studded with long daggerlike teeth, often combined with a very distensible stomach, to be capable of swallowing relatively large prey. These striking features can be observed in members of the marine teleost family Stomiidae. The present study gives a detailed morphological description of the mesopelagic predatory fish, Stomias boa, based on a combined approach of clearing and double staining, serial sections and dissection. In this genus, large pads made of dense connective tissue extend from the first enlarged neural arch to the ventral side of the chordal sheath, embracing the prominent exoccipitals and thus constituting a kind of double ball‐ and socket joint for the head. The notochordal occipito‐vertebral gap is enlarged, probably not by loss of vertebral centra as is proposed for other genera of the stomiid family, e.g., in Astronesthes or Photostomias. We conclude that this “pseudo‐craniovertebral articulation” serves as a functional substitute for the absent vertebrae and strengthens the flexible, anterior part of the vertebral column during extreme dorsal expansion of the gape during prey capture and swallowing. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Deep‐UV surface‐enhanced Raman scattering
Authors: Dörfer Thomas , Schmitt Michael , Popp Jürgen
Published: October 2007

The presented work demonstrates, to the best of our knowledge, for the first time the capability of an aluminium surface to act as an SERS‐active substrate for deep‐UV excitation wavelengths. Copyright © 2007 John Wiley & Sons, Ltd.
Capability of thermodynamic calculation in the development of alloys for deposition of corrosion‐protection coatings via thermal spraying
Authors: Born M. , Korb J. , Rafaja D. , Dopita M. , Schülein R. W.
Published: October 2007

The capability of thermodynamic calculations for the development of materials for corrosion protection of steels via thermal spraying is illustrated in several practical examples. Although the thermodynamic calculations are usually performed for the equilibrium state, they can yield important information even about fast chemical reactions that are far from the equilibrium conditions. The relevance and reliability of thermodynamic calculations can be improved significantly if their results are complemented by chemical and microstructural analyses. In this contribution, details on the melting and alloying processes in technically relevant nickel‐based alloys were obtained from the combination of the thermodynamic calculations, differential thermal analysis, local chemical analysis using scanning electron microscopy with energy dispersive spectroscopy of characteristic X‐rays and X‐ray diffraction analysis. Furthermore, the results of the thermodynamic calculations performed on nickel‐based alloys clarified the role of individual chemical elements dissolved in the alloys for the corrosion resistance of the alloys and thus they contributed to the improvement of the chemical stability of these alloys during the chemical reaction with gaseous substances containing chlorine.
Zinc‐Aluminium‐Coatings as Corrosion Protection for Steel
Authors: Büteführ M.
Published: October 2007

An analysis was made to investigate the influence of the alloying of sprayed coatings on the corrosion performance in climates of practical relevance and to evaluate the optimised alloy compositions. Furthermore, the mechanism of corrosion and coating formation was evaluated. The protective effect increased up to an aluminium content of 15 and 22 wt%, respectively, with corrosion rates below 1 µm per year.

Electrochemical investigations found a distinctive decrease in the cathodic reaction together with an accumulation of aluminium in per cent and a depletion of zinc. Due to the increasing concentration of aluminium within the layer and the correlated presence of inhibitive corrosion products, the cathodic reaction and therefore the corrosion of the sprayed zinc‐aluminium coatings can be increasingly eliminated.
A Novel Strategy for the Preparation of Reactively Compatibilized Polymer Blends with Oligomers Containing α‐Methyl Styrene Units
Authors: Deng Jianping , Liang Shujun , Zhang Cairong , Yang Wantai
Published: October 2007

A novel strategy to prepare reactively compatibilized polymer blends is reported. An oligomer that consists of AMS (α‐methyl styrene) and GMA (glycidyl methacrylate) is initially synthesized. When this oligomer is melt blended with poly(propylene) (PP), the GMA units in the oligomer are successfully grafted onto the PP chain, which is proven by measuring the FT‐IR spectrum of the blended PP. When the oligomer is added to a blend of PP/Ny66, an in‐situ compatibilization occurs, which leads to an increase in torque values during blending, a decrease in crystallinity degree of Ny66, and is observed by SEM images of the resulting blends. The compatibilizing effects of the oligomer are also observed in PP/Ny6 and polyethylene/Ny6 blends. A relevant compatibilization mechanism is proposed.

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Live rats resulting from injection of oocytes with spermatozoa freeze‐dried and stored for one year
Authors: Hochi Shinichi , Watanabe Kaori , Kato Megumi , Hirabayashi Masumi
Published: October 2007

This study was designed to examine whether rat spermatozoa after freeze‐drying and 1‐year storage can participate in full‐term development following intracytoplasmic sperm injection (ICSI). Cauda epididymal spermatozoa from Crlj:Wistar rats were frozen in liquid nitrogen (LN2), first dried for 14 hr at 0.37 hPa and then for 3 hr at 0.001 hPa. The dried spermatozoa were stored for 1 year in a desiccator at +25°C, or in a refrigerator at +4°C, or in LN2 at −196°C. Controls consisted of sperm that had only been frozen and stored in LN2. After being stored, spermatozoa were sonicated to dissociate the sperm tail and were injected into oocytes from superovulated Slc:SD rats. The respective fertilization rates of oocytes injected with frozen sperm, or with freeze‐dried sperm stored at +25, +4, and −196°C were 79%, 75%, 70%, and 73%. However, the corresponding cleavage rates of injected oocytes were 63%, 1%, 38%, and 36%. After transfer of >80 zygotes of each group into recipients, the respective percentages of full‐term normal offspring resulting from frozen sperm or from freeze‐dried sperm stored at +25, +4, and −196°C were 36%, 0%, 7%, and 14%. These results demonstrate that the storage temperature significantly influenced the likelihood of term development of rats produced by injection of oocytes with freeze‐dried spermatozoa. Chromosomal analysis of the rat spermatozoa in the ICSI oocytes indicated that chromosomal aberration in freeze‐dried spermatozoa stored at +25°C (100%) occurred more frequently than in frozen control spermatozoa (41%) and freeze‐dried spermatozoa stored at −196°C (35%), and the frequency of chromosomal aberrations in freeze‐dried spermatozoa stored at +4°C (65%) was the intermediate. In conclusion, rat spermatozoa freeze‐dried and stored at +4°C for 1 year are capable of participating in full‐term development after ICSI. Mol. Reprod. Dev. 75: 890–894, 2008. © 2007 Wiley‐Liss, Inc.
Can a faked cystometry deceive patients in their perception of filling sensations? A study on the reliability of spontaneously reported cystometric filling sensations in patients with non‐neurogenic lower urinary tract dysfunction
Authors: De Wachter Stefan , Van Meel Tom David , Wyndaele Jean Jacques
Published: October 2007

Aims

To evaluate the reliability of spontaneously reported bladder sensations during real and faked cystometry in patients with non‐neurogenic lower urinary tract dysfunction.

Methods

Fifty‐nine patients with non‐neurogenic lower urinary tract dysfunction were submitted to a real and faked filling cystometry and were asked to describe all bladder‐related sensations they experienced during the investigations. All patients were told that the bladder had to be filled twice, but during the faked cystometry, no water was infused in the bladder.

Results

During the real cystometry, the normal pattern of filling sensation was reported by 88%. During the faked cystometry, none of the patients reported the normal pattern of filling sensations. Five patients reported first sensation of filling, one first desire to void (FDV). None of the patients reported a strong desire to void (SDV) during the faked cystometry.

Conclusions

Asking patients with a non‐neurogenic lower urinary tract dysfunction to report on the bladder filling sensations during cystometry is a valid method for sensory evaluation. A minority of patients may report some sensation of bladder filling even without actual bladder filling. Memory and habituation may play a role in the perception of bladder sensation and one should be aware of this. However, reporting some sensation during faked cystometry not necessarily means the evaluation of the perception of bladder filling is unreliable. Neurourol. Urodynam. 27:395–398, 2008. © 2007 Wiley‐Liss, Inc.
Reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene using novel heterocycle‐containing chain transfer agents
Authors: Babu Rajendran Prakash , Dhamodharan Raghavachari
Published: October 2007

BACKGROUND: Controlled/‘living’ radical polymerization is a new and robust method to synthesize polymers with predetermined molecular weight, narrow polydispersity and tailored architecture. Several methods have been developed but reversible addition‐fragmentation chain transfer (RAFT) has several advantages over the other methods. It has been reported that the effectiveness of RAFT agents depends strongly on the nature of the Z and R groups.

RESULTS: Three new dithiocarbamates, namely (2‐ethoxy carbonyl)‐prop‐2‐yl‐pyrrole‐1‐carbodithioate (CTA‐A), (1‐phenyl ethyl)‐pyrazole‐1‐carbodithioate (CTA‐B) and (2‐ethoxy carbonyl)‐prop‐2‐yl‐pyrazole‐1‐carbodithioate (CTA‐C), were synthesized for studying the effect of the Z and R group of a chain transfer agent on the RAFT polymerization of styrene, initiated by 2,2′‐azobisisobutyronitrile. Well‐controlled molecular weight with narrow polydispersity (1.10–1.46) was achieved. The increase in molecular weight with conversion is linear and follows first‐order kinetics.

CONCLUSION: The detailed kinetic results show that the structure of the activating (Z) group of dithiocarbamates has significant effects on the reactivity of dithiocarbamates towards the polymerization of styrene. In the homopolymerization of styrene it was found that, from the polydispersity index of polystyrenes obtained and the kinetic results, the pyrazole‐based dithiocarbamates (CTA‐B and CTA‐C) are very effective compared to the pyrrole‐based dithiocarbamate (CTA‐A). All the polymerizations show controlled living characters. Copyright © 2007 Society of Chemical Industry
Lipid laden macrophage indices and reflux finding score in canine gastroesophageal reflux model
Authors: Nino Gustavo , Savchenko Oleg , Vastola Paul , Pagala Murali , Dhadwal Ajay K. , Vaynblat Mikhail , Marcus Michael , Kazachkov Mikhail
Published: October 2007

Laryngeal exposure to acid and aspiration of gastric contents may lead to severe respiratory disorders. This study utilizes the canine model of Gastroesophageal reflux (GER) to identify whether lower esophageal dysfunction is associated with upper and lower airway pathology.

Materials and Methods

Five mongrel dogs underwent GER‐creating surgery (partial cardiomyectomy). Laryngeal reflux finding score (RFS), lipid‐laden macrophage index (LLMI) and BAL fluid cell differential were obtained before and after surgery.

Results

Partial cardiomyectomy in dogs significantly increased the Reflux index (RI) from 0.38 ± 0.21% to 7.56 ± 2.89% (P = 0.048), the duration of the longest reflux episode (DLRE) from 1.22 ± 1.19 min to 66.2 ± 42.03 min postoperatively (P = 0.049) and the total number of episodes in 24 hr from 2.06 ± 1.03 to a postoperative value of 19.24 ± 4.79. There was no statistically significant change in values for RFS, LLMI, and BAL fluid cell differential after the induction of GER.

Conclusions

Acid reflux to the proximal esophagus of this animal model did not cause laryngeal exposure to acid or aspiration of gastric content. The results of this study suggest that presence of GER, secondary to lower esophageal dysfunction is not necessarily associated with upper and lower airway pathology. Pediatr Pulmonol. 2007; 42:1181–1186. © 2007 Wiley‐Liss, Inc.
Robotic radical hysterectomy in early‐stage cervical carcinoma patients, comparing results with total laparoscopic radical hysterectomy cases. The future is now?
Authors: Sert B. , Abeler V.
Published: October 2007

Background

We evaluated the feasibility and efficacy of robotic‐assisted laparoscopic radical hysterectomy and bilateral pelvic lymph node dissection for early cervical carcinoma, comparing the results with those from conventional total laparoscopic radical hysterectomy.

Methods

Type II and III radical hysterectomies were performed in 15 patients with early‐stage cervical carcinoma as a pilot case‐control study at a comprehensive cancer center–university teaching hospital setting. The adequacy of the operations was determined and documented in DVD/video.

Results

All operations were performed according to a well‐established study protocol. No conversions or technical incidents were observed in the robotic group. Median operation time was 241 and 300 min in the robotic and conventional laparoscopic groups, respectively (p = 0.165). The histopathological results concerning the number of lymph nodes, the parametrial tissue and vaginal cuff size were similar in both groups. Less bleeding and a shorter hospital stay were observed in the robotic‐assisted group (p = 0.038 and p = 0.004, respectively).

Conclusions

Although the benefits of this technique have not yet been established in a prospective randomized manner, we showed the technical feasibility of robotic‐assisted laparoscopic radical hysterectomy in early‐stage cervical carcinoma cases and better results than with traditional total laparoscopic radical hysterectomy. Copyright © 2007 John Wiley & Sons, Ltd.
ZIC1 gene expression is controlled by DNA and histone methylation in mesenchymal proliferations
Authors: Pourebrahim Rasoul , Van Dam Kim , Bauters Marijke , De Wever Ivo , Sciot Raf , Cassiman Jean-Jacques , Tejpar Sabine
Published: October 2007

RNA and protein analysis revealed the consistent upregulation of the neural transcription factors ZIC1 and ZIC4 in desmoid tumors and other fibroproliferative disorders. The 5′ flanking region of the ZIC1 promoter was unmethylated in desmoid tumor fibroblasts, while a hypermethylated ZIC1 promoter was found in human and mouse cell lines not expressing the gene. In addition, expressing cells showed a H3K4me2 at the ZIC1 promoter, whereas non‐expressing cells showed higher levels of H3K9me2 in the same region. To our knowledge, this is the first report describing ZIC1 expression in mesenchymal proliferations and a role for DNA methylation in the control of ZIC1 expression.
Characterization of ScORK28, a transmembrane functional protein receptor kinase predominantly expressed in ovaries from the wild potato species Solanum chacoense
Authors: Germain Hugo , Houde Josée , Gray-Mitsumune Madoka , Sawasaki Tatsuya , Endo Yaeta , Rivoal Jean , Matton Daniel P.
Published: October 2007

Solanum chacoense ovule receptor kinase 28 (ScORK28) was found among 30 receptor kinases from an ovule cDNA library enriched for weakly expressed mRNAs. This LRR‐RLK displayed high level of tissue specificity at the RNA and protein levels and was predominantly expressed in female reproductive tissues. Protein expression analyses in planta revealed that ScORK28 was N‐glycosylated and ScORK28::GFP fusion analyses showed that it was localized at the plasma membrane. Bacterial expression of ScORK28 catalytic domain followed by kinase activity assays revealed that ScORK28 is an active Mg2+‐dependent protein kinase and that the juxtamembrane domain is necessary for kinase activity.
Moderate alcohol consumption and the immune system: A review
Authors: Romeo Javier , Wärnberg Julia , Nova Esther , Díaz Ligia E. , Gómez-Martinez Sonia , Marcos Ascensión
Published: October 2007

Increasing evidence suggests that light to moderate amounts of polyphenol-rich alcoholic beverages like wine or beer could have health benefits. Scientists have long debated the effects of alcohol on immune function, showing on the one hand, that high doses of alcohol consumption can directly suppress a wide range of immune responses, and that alcohol abuse is associated with an increased incidence of a number of infectious diseases. On the other hand, moderate alcohol consumption seems to have a beneficial impact on the immune system compared to alcohol abuse or abstinence. Therefore, the link between alcohol consumption, immune response, as well as infectious and inflammatory processes remains not completely understood. With this in mind, it is important to realise that other factors, unrelated or indirectly related to immune function, like drinking patterns, beverage type, amount of alcohol, or gender differences, will affect the influence that alcohol consumption may have on the immune system. This review summarises published data describing the effects that light to moderate amounts of polyphenol-rich beverages like wine or beer seem to have on immunity in healthy adults.
Efforts to emulate human milk oligosaccharides
Authors: María Espinosa Rosa , Taméz Martha , Prieto Pedro
Published: October 2007

Research on human milk oligosaccharides (HMO) began with the characterisation of their chemical structures and is now focused on the elucidation of their biological roles. Previously, biological effects could only be investigated with fractions or structures isolated from breast milk; consequently, clinical observations were limited to comparisons between outcomes from breast-fed infants and their formula-fed counterparts. In some cases, it was inferred that the observed differences were caused by the presence of HMO in breast milk. Presently, analytical techniques allow for the fast analysis of milk samples, thus providing insights on the inherent variability of specimens. In addition, methods for the synthesis of HMO have provided single structures in sufficient quantities to perform clinical studies with oligosaccharide-supplemented formulae. Furthermore, studies have been conducted with non-mammalian oligosaccharides with the purpose of assessing the suitability of these structures to functionally emulate HMO. Taken together, these developments justify summarising current knowledge on HMO to further discussions on efforts to emulate human milk in regard to its oligosaccharide content. The present account summarises published data and intends to provide an historical context and to illustrate the state of the field.
A novel minimal model to describe non-esterified fatty acid kinetics in Holstein dairy cows
Authors: Boston Raymond C , Roche John R , Ward Glen M , Moate Peter J
Published: October 2007

The dynamics of non-esterified fatty acid (NEFA) metabolism in lactating dairy cows requires quantification if we are to understand how dietary treatments and disease influence changes in body condition (adipose reserves) and the production of milk fat. We present here a novel compartmental model that employs the pattern of plasma glucose concentrations to predict the dynamic changes that occur in plasma NEFA concentrations during an intravenous glucose tolerance test (IVGTT) in lactating dairy cows. The model was developed using data obtained from ten early-lactation, Holstein-Friesian cows given a standard IVGTT. The model described all of the major features of the NEFA response to an IVGTT; it was consistent with physiological processes and provided a number of parameters that can be used to quantify NEFA production and utilization. For all of the individual cows, all model parameters were well identified and usually had CV<10% of their estimated values. In the model, elevated plasma glucose concentrations cause an increase in the level of glucose in a remote compartment, which in turn suppresses the rate of entry of NEFA to the plasma compartment. The means (±sd) for the five adjustable parameters of the model were: rate of entry of NEFA to the plasma pool (SFFA) 183±71 [μmol l−1 min−1], rate of removal (oxidation, sequestration in adipose tissue and uptake by the mammary gland for milk production) of NEFA from the plasma pool (KFFA) 0·140±0·047 [min−1], a threshold parameter (gs) representing a plasma glucose concentration above which elevated levels of plasma glucose result in entry of glucose into a ‘remote’ or inaccessible glucose compartment, 3·30±0·52 [mmol/l], a rate constant (K) describing the movement of plasma glucose (above gs) into a remote compartment 0·063±0·033 [min−1] and a parameter Φ which is a Michaelis Menten type affinity constant which modulates the extent to which remote glucose inhibits the provision of NEFA to the plasma pool, 0·812±0·276 [mmol/l]. It is concluded that the model is suitable to describe NEFA kinetics in lactating dairy cows and it may have application in other species.
Anti-Trypanosoma cruzieffects of cyclosporin A derivatives: possible role of a P-glycoprotein and parasite cyclophilins
Authors: BÚA J. , FICHERA L. E. , FUCHS A. G. , POTENZA M. , DUBIN M. , WENGER R. O. , MORETTI G. , SCABONE C. M. , RUIZ A. M.
Published: October 2007

Cyclophilins are target molecules for cyclosporin A (CsA), an immunosuppressive antimicrobial drug. We have previously reported thein vitroanti-Trypanosoma cruziactivity of H-7-94 and F-7-62 non-immunosuppressive CsA analogues. In this work, we continue the study of the parasiticidal effect of H-7-94 and F-7-62 CsA analoguesin vitroandin vivoand we analyse 3 new CsA derivatives: MeIle-4-CsA (NIM 811), MeVal-4-CsA (MeVal-4) and D-MeAla-3-EtVal-4-CsA, (EtVal-4). The most efficient anti-T. cruzieffect was observed with H-7-94, F-7-62 and MeVal-4 CsA analogues evidenced as inhibition of epimastigote proliferation, trypomastigote penetration, intracellular amastigote development andin vivo T. cruziinfection. This trypanocidal activity could be due to inhibition of the peptidyl prolylcis-transisomerase activity on theT. cruzirecombinant cyclophilins tested. Furthermore, CsA and F-7-62 derivative inhibited the efflux of rhodamine 123 fromT. cruziepimastigotes, suggesting an interference with a P-glycoprotein activity. Moreover, H-7-94 and F-7-62 CsA analogues were not toxic as shown by cell viability and by aminopyrine-N-demethylase activity on mammalian cells. Our results show that H-7-94, F-7-62 and MeVal-4 CsA analogues expressed the highest inhibiting effects onT. cruzi, being promissory parasiticidal drugs worthy of further studies.