bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of micropump‐actuated negative pressure pinched injection for parallel electrophoresis on array microfluidic chip
Authors: Li Bowei , Jiang Lei , Xie Hua , Gao Yan , Qin Jianhua , Lin Bingcheng
Published: August 2009

A micropump‐actuated negative pressure pinched injection method is developed for parallel electrophoresis on a multi‐channel LIF detection system. The system has a home‐made device that could individually control 16‐port solenoid valves and a high‐voltage power supply. The laser beam is excitated and distributes to the array separation channels for detection. The hybrid Glass‐PDMS microfluidic chip comprises two common reservoirs, four separation channels coupled to their respective pneumatic micropumps and two reference channels. Due to use of pressure as a driving force, the proposed method has no sample bias effect for separation. There is only one high‐voltage supply needed for separation without relying on the number of channels, which is significant for high‐throughput analysis, and the time for sample loading is shortened to 1 s. In addition, the integrated micropumps can provide the versatile interface for coupling with other function units to satisfy the complicated demands. The performance is verified by separation of DNA marker and Hepatitis B virus DNA samples. And this method is also expected to show the potential throughput for the DNA analysis in the field of disease diagnosis.
Potentiometric titrations for the characterization of functional groups on solid wastes of the olive oil production
Authors: Calero Mónica , Hernáinz Francisco , Blázquez Gabriel , Martín‐Lara María Ángeles
Published: August 2009

In this article, the identification and quantification of the acid active sites present in three solid materials, namely, olive stone, olive mill waste‐water (alpeorujo), and olive tree pruning have been made, as the first step to assess their possible use as biosorbents of heavy metals. Using the continuous potentiometric titration technique, the effect of the atmosphere in the titrator and the time interval between successive additions of titrant has been studied. Potentiometric titrations on the biosorbents subjected to selective extractions (for elimination of fat compounds and polyphenols) and pretreated by acids have been also carried out. Modeling of the experimental data demonstrated that the acid‐base properties of these solids were of a complex nature and could be described considering the presence of three different types of surface functional groups; two of which are presumably carboxyl and hydroxyl groups. © 2009 American Institute of Chemical Engineers Environ Prog, 2010
A two‐dimensional finite volume morphodynamic model on unstructured triangular grids
Authors: Benkhaldoun Fayssal , Sahmim Slah , Seaïd Mohammed
Published: August 2009

We discuss the application of a finite volume method to morphodynamic models on unstructured triangular meshes. The model is based on coupling the shallow water equations for the hydrodynamics with a sediment transport equation for the morphodynamics. The finite volume method is formulated for the quasi‐steady approach and the coupled approach. In the first approach, the steady hydrodynamic state is calculated first and the corresponding water velocity is used in the sediment transport equation to be solved subsequently. The second approach solves the coupled hydrodynamics and sediment transport system within the same time step. The gradient fluxes are discretized using a modified Roe's scheme incorporating the sign of the Jacobian matrix in the morphodynamic system. A well‐balanced discretization is used for the treatment of source terms. We also describe an adaptive procedure in the finite volume method by monitoring the bed–load in the computational domain during its transport process. The method uses unstructured meshes, incorporates upwinded numerical fluxes and slope limiters to provide sharp resolution of steep bed gradients that may form in the approximate solution. Numerical results are shown for a test problem in the evolution of an initially hump‐shaped bed in a squared channel. For the considered morphodynamical regimes, the obtained results point out that the coupled approach performs better than the quasi‐steady approach only when the bed–load rapidly interacts with the hydrodynamics. Copyright © 2009 John Wiley & Sons, Ltd.
The cost of diagnosing dementia in a community setting
Authors: Jedenius Erik , Wimo Anders , Strömqvist Jan , Jönsson Linus , Andreasen Niels
Published: August 2009

Objectives

In order to cope with the increasing number of individuals with dementia, it is crucial to develop the diagnostic capacity in primary care in cooperation with dementia specialists. Further, in order to establish prerequisites for care and planning it is important to identify the cost of dementia diagnosis. This study aims to evaluate the cost of establishing a dementia diagnosis.

Methods

This is a prospective, time‐ and resource utilization study for the identification of the total cost associated with diagnosing dementia (from start of the diagnostic process to time for established or rejected dementia diagnosis) both at the specialist and primary care level.

Results

Dementia evaluation in primary care took between 2 weeks and 2 months before reaching diagnosis. The average cost for all patients evaluated at the primary care level was 477 Euro (€), whereas evaluations done on a specialist level reached a cost of 1115 €. Thus, the costs per true diagnosed case consist of the cost for all dementia investigations divided by the number of finalized diagnoses.

Conclusions

In this study the cost for diagnosing dementia per true diagnosed patient is 849 € at the primary care level and 1334 € at the specialist level. Based on this result we estimated that the cost of establishing a dementia diagnosis is 1% of the total cost of dementia. Copyright © 2009 John Wiley & Sons, Ltd.
PI3K pathway activation in breast cancer is associated with the basal‐like phenotype and cancer‐specific mortality
Authors: López‐Knowles Elena , O'Toole Sandra A. , McNeil Catriona M. , Millar Ewan K.A. , Qiu Min R. , Crea Paul , Daly Roger J. , Musgrove Elizabeth A. , Sutherland Robert L.
Published: August 2009

Breast cancer is a common malignancy with current biological therapies tailored to steroid hormone (ER, PR) and HER2 receptor status. Understanding the biological basis of resistance to current targeted therapies and the identification of new potential therapeutic targets is an ongoing challenge. The PI3K pathway is altered in a high proportion of breast cancers and may contribute to therapeutic resistance. We undertook an integrative study of mutational, copy number and expression analyses of key regulators of the PI3K pathway in a cohort of 292 invasive breast cancer patients with known treatment outcomes. The alterations identified in this cohort included PIK3CA mutations (12/168, i.e. 7%), PIK3CA copy number gain (28/209, i.e. 14%), PTEN loss (73/258, i.e. 28%) and AKT activation (62/258, i.e. 24%). Overall at least 1 parameter was altered in 72% (139/193) of primary breast cancers. PI3K pathway activation was significantly associated with ER negative (p = 0.0008) and PR negative (p = 0.006) status, high tumor grade (p = 0.032) and a “basal‐like” phenotype (p = 0.01), where 92% (25/27) of tumors had an altered pathway. In univariate analysis, PI3K pathway aberrations were associated with death from breast cancer; however, this relationship was not maintained in multivariate analysis. No association was identified between an activated pathway and outcome in tamoxifen‐ or chemotherapy‐treated patients. We concluded that >70% of breast cancers have an alteration in at least 1 component of the PI3K pathway and this might be exploited to therapeutic advantage especially in “basal‐like” cancers.
Toll‐like receptors on B‐CLL cells: expression and functional consequences of their stimulation
Authors: Rožková Daniela , Novotná Linda , Pytlík Robert , Hochová Ivana , Kozák Tomáš , Bartůňková Jiřina , Špíšek Radek
Published: August 2009

Toll‐like receptor (TLR) stimulation plays a crucial role in the homeostasis of human B cells. We investigated the expression of TLRs 1–9 on the cells of B‐cell chronic lymphocytic leukemia (B‐CLL) and analyzed the functional consequences of TLR stimulation on leukemic cells. We showed that B‐CLL cells express similar set of TLRs as memory B cells of healthy donors, i.e. TLR‐1, TLR‐2, TLR‐6, TLR‐7 and TLR‐9. However, in contrast to memory B cells, B‐CLL cells lack TLR‐4 expression. Expression of TLRs correlates with their capacity to respond to specific TLR agonists. At the level of phenotype, ODN2006 (TLR‐9 agonist) is the most potent stimulus. B‐CLL cells also respond to the stimulation with loxoribine, Pam3CSK4 and MALP‐2 (TLR‐7, TLR1/TLR2 and TLR2/TLR6 agonists, respectively). TLR‐7 and TLR‐9 stimulation induces production of IL‐6 and TNFα. In 47% of tested patients, treatment with ODN2006, MALP‐2 and Pam3CSK4 reduced leukemic cells survival. Stimulation of B‐CLL cells with TLR‐9 agonists, loxoribine, MALP‐2 and Pam3CSK4 induces significant proliferation. We report that TLR stimulation induces expression of CD38, a negative prognostic marker, on B‐CLL cells. Expression of CD38 is induced by direct stimulation of B‐CLL cells through TLR‐7 and TLR‐9 or CD38 can be induced on B‐CLL cells indirectly by a soluble factor induced in non‐B‐CLL cells after stimulation with TLR‐2, TLR‐3 or TLR‐5 agonists; the nature of this factor remains unknown. Our results argue for cautious evaluation of immunointervention strategies based on the administration of TLR agonists in the treatment of B‐CLL as their effects on B‐CLL cells may be tumor promoting as well as tumor suppressing.
Productive infection of Piscirickettsia salmonis in macrophages and monocyte‐like cells from rainbow trout, a possible survival strategy
Authors: Rojas Verónica , Galanti Norbel , Bols Niels C. , Marshall Sergio H.
Published: August 2009

Piscirickettsia salmonis is the etiologic agent of the salmonid rickettsial septicemia (SRS), an endemic disease which causes significant losses in salmon production. This intracellular bacterium is normally cultured in salmonid epithelial cell lines inducing characteristic cytopathic effects (CPEs). In this study we demonstrate that P. salmonis is able to infect, survive, replicate, and propagate in the macrophages/monocytes cell line RTS11 derived from rainbow trout spleen, without inducing the characteristic CPEs and the host cells showing the same expression levels as non‐infected control cell. On the other hand, bacteria were capable of expressing specific proteins within infected cells. Infected macrophages cease proliferation and a fraction of them detached from the plate, transform to non‐adhesive, monocyte‐like cells with proliferative activity. Productive infection of P. salmonis into salmonid macrophage/monocyte cells in culture provides an excellent model for the study of host–pathogen interactions, almost unknown in the case of P. salmonis. Our results suggest that the infection of cells from the salmonid innate immune system without inducing an important cell death response should lead to the persistence of the bacteria and consequently their dissemination to other tissues, favoring the evasion of the first line of defense against pathogens. J. Cell. Biochem. 108: 631–637, 2009. © 2009 Wiley‐Liss, Inc.
Contribution of the fibrinolytic pathway to hematopoietic regeneration
Authors: Heissig Beate , Ohki Makiko , Ishihara Makoto , Tashiro Yoshihiko , Nishida Chiemi , Gritli Ismael , Rosenkvist Jeanette , Hattori Koichi
Published: August 2009

Hematopoietic stem cells (HSCs) can differentiate and proliferate in response to hematopoietic stress (e.g., myelosuppression, infections, and allergic reactions), thereby ensuring a well‐regulated supply of mature and immature hematopoietic cells within the circulation and prompt adjustment of blood cell levels within normal ranges. The recovery of tissues and organs from hematopoietic stress (e.g., myelosuppression or ionizing irradiation) is dependent on two cell types: resident HSCs which repopulate the bone marrow (BM) cavity, and stromal cells. BM regeneration critically depends on the release of soluble factors from cells such as stromal cells, a process regulated by proteases. Two proteolytic systems, the fibrinolytic system and the matrix metalloproteinases (MMPs), have recently been shown to be involved in this process (Heissig B, 2007, Cell Stem Cell 1: 658–670). The plasminogen/plasmin system is mostly recognized for its fibrinolytic activity, but it is also involved in processes such as cell invasion, chemotaxis, growth factor activity modulation, and tissue remodeling. This review focuses on the role of plasmin and its activators as key players in controlling the hematopoietic stress response after myelosuppression (hematopoietic regeneration). Aspects of plasmin regulation, especially regulation of its ability to activate MMPs and the functional consequences of this enzyme activation, such as plasmin‐mediated release of biologically relevant cytokines from the matrix and cell surfaces, will be discussed. J. Cell. Physiol. 221: 521–525, 2009. © 2009 Wiley‐Liss, Inc.
Two types of organophosphate pesticides and their combined effects on heterotrophic growth rates in activated sludge process
Authors: Pai Tzu‐Yi , Wang Shun‐Cheng , Lin Ching‐Yuan , Liao Wan‐Chun , Chu Hsiao‐Hsing , Lin Tung‐Sheng , Liu Chun‐Chih , Lin Shu‐Wen
Published: August 2009

BACKGROUND: Pesticides are sometimes non‐biodegradable and, moreover, toxic to microorganisms. If pesticides exceed the tolerance of microorganisms, failure of the activated sludge process (ASP) occurs. Therefore the effects of two types of organophosphate pesticides on heterotrophic growth rate constant in sludge from ASP were investigated. Oxygen uptake rate was employed to measure the rate constants.

RESULTS: The results indicated that the value of heterotrophic growth rate constant decreased from 3.88 d−1 to 1.46 d−1 or by 62% when 0.5 mg L−1 of glyphosate was added. When adding 0.5 mg L−1 of malathion, the value of heterotrophic growth rate constant decreased to 1.33 d−1 or by 66%. The value of heterotrophic growth rate constant decreased to 1.98 d−1 or by 49% when 0.5 mg L−1 of pesticide combination (50% for each) was added.

CONCLUSIONS: The inhibitory effects of glyphosate and malathion were in good agreement with non‐competitive inhibition kinetics, but pesticide combination did not follow non‐competitive kinetics. The inhibition coefficient values for glyphosate, malathion and their combination were 0.29, 0.29 and 0.58 mg L−1, respectively. For comparison, linear and exponential types of models were derived by regression. According to non‐competitive kinetics, and linear and exponential models, the inhibitory effects of glyphosate and malathion were almost consistent. Finally, the degree of inhibition was simulated using different types of model. It was found that the toxicity of the two pesticides agreed with the antagonism well. Copyright © 2009 Society of Chemical Industry
Measurement of the overall volumetric oxygen transfer coefficient in alkane‐aqueous dispersions
Authors: Correia Leslie DC , Clarke Kim G
Published: August 2009

BACKGROUND: A reliable procedure for the determination of the volumetric oxygen transfer coefficient (KLa) in hydrocarbon–aqueous dispersions is critical to the assessment of oxygen transfer in hydrocarbon‐based bioprocesses. The pressure step procedure (PSP) and gassing out procedure (GOP) for KLa determination were evaluated in n‐C10–13 alkane–aqueous dispersions over agitation rates (600 to 1200 rpm) and alkane concentrations (up to 20%) typical of hydrocarbon‐based bioprocesses.

RESULTS: KLa from the procedures diverged progressively as agitation increased, with KLa underprediction attenuated at high alkane. At 1200 rpm and 5% alkane, KLa from the GOP was underpredicted by 49%. Compared with KLa from the PSP, KLa from the PSP without nitrogen transport was the same, but KLa from the PSP without response lag (PSP‐lag) was underpredicted by approximately 50% at 1200 rpm. Moreover, KLa from the PSP‐lag was lower than KLa from the GOP, except at 1200 rpm and alkane concentration up to 5%.

CONCLUSION: The PSP was superior to the GOP in alkane–aqueous dispersions, particularly at extreme agitation and low alkane concentrations. This was attributable to the probe response lag and the non‐uniformity of gas composition inherent in the GOP and independent of the rate of coincident nitrogen transport. Copyright © 2009 Society of Chemical Industry
Ambient imaging mass spectrometry by electrospray ionization using solid needle as sampling probe
Authors: Chen Lee Chuin , Yoshimura Kentaro , Yu Zhan , Iwata Rikiya , Ito Hajime , Suzuki Hiroaki , Mori Kunihiko , Ariyada Osamu , Takeda Sen , Kubota Takeo , Hiraoka Kenzo
Published: August 2009

Although being an atmospheric pressure ion source, electrospray ionization (ESI) has rarely been used directly for ambient imaging mass spectrometry because the sample has to be introduced as liquid solution through the capillary. Instead of capillary, probe electrospray ionization (PESI), which has been developed recently, uses a solid needle as the sampling probe, as well as the electrospray emitter, and has been applied not only for liquid solutions but also for the direct sampling on wet samples. Biological tissues are composed of cells that contain 70–90% water, and when the surface is probed by the needle tip, the biological fluid adhering to the needle can be electrosprayed directly or assisted by additional solvent added onto the needle surface. Here, we demonstrate ambient imaging mass spectrometry of mouse brain section using PESI, incorporated with an auxiliary heated capillary sprayer. The solvent vapor generated from the sprayer condensed on the needle tip, re‐dissolving the adhered sample, and at the same time, providing an indirect means for needle cleaning. The histological sections were prepared by fixation using paraformaldehyde, and the spatial analysis was automated by maintaining an equal sampling depth into the sample in addition to raster scan. Phospholipids and galactosylceramides were readily detected from the mouse brain section in the positive ion mode, and were mapped with 60 µm lateral resolution to form mass spectrometric images. Copyright © 2009 John Wiley & Sons, Ltd.
Spatial variation of soil test phosphorus in a long‐term grazed experimental grassland field
Authors: Fu Weijun , Tunney Hubert , Zhang Chaosheng
Published: August 2009

The spatial variation of soil test P (STP) in grassland soils is becoming important because of the use of STP as a basis for policies such as the recently EU‐introduced Nitrate Directive. This research investigates the spatial variation of soil P in grazed grassland plots with a long‐term (38 y) experiment. A total of 326 soil samples (including 14 samples from an adjacent grass‐wood buffer zone) were collected based on a 10 × 10 m2grid system. The samples were measured for STP and other nutrients. The results were analyzed using conventional statistics, geostatistics, and a geographic information system (GIS).

Soil test P concentrations followed a lognormal distribution, with a median of 5.30 mg L–1and a geometric mean of 5.35 mg L–1. Statistically significant (p< 0.01) positive correlation between STP and pH was found. Spatial clusters and spatial outliers were detected using the local Moran's I index (a local indicator of spatial association) and were mapped using GIS. An obvious low‐value spatial‐cluster area was observed on the plots that received zero‐P fertilizer application from 1968 to 1998 and a large high‐value spatial‐cluster area was found on the relatively high‐P fertilizer application plots (15 kg ha–1y–1). The local Moran's I index was also effective in detecting spatial outliers, especially at locations close to spatial‐cluster areas. To obtain a reliable and stable spatial structure, semivariogram of soil‐P data was produced after elimination of spatial outliers. A spherical model with a nugget effect was chosen to fit the experimental semivariogram. The spatial‐distribution map of soil P was produced using the kriging interpolation method. The interpolated distribution map was dominated by medium STP values, ranging from 3 mg to 8 mg L–1. An evidently low‐P‐value area was present in the upper side of the study area, as zero or short‐term P fertilizer was applied on the plots. Meanwhile, high‐P‐value area was located mainly on the plots receiving 15 kg P ha–1y–1(for 38 y) as these plots accumulated excess P after a long‐term P‐fertilizer spreading. The high‐ or low‐value patterns were in line with the spatial clusters. Geostatistics, combined with GIS and the local spatial autocorrelation index, provides a useful tool for analyzing the spatial variation in soil nutrients.
Some Holocene palaeoclimatic and palaeoenvironmental perspectives on Arctic/Subarctic climate warming and the IPCC 4th Assessment Report
Authors: MacDonald Glen M.
Published: August 2009

The IPCC 4th Assessment Report (FAR) is considered in light of Holocene palaeo‐records of Arctic and Subarctic land temperatures and the response of the boreal forest–tundra boundary to past and present warming. The palaeo‐records appear to support and amplify some of the conclusions in FAR and raise questions about others. Comparison of the FAR estimates for late 21st‐century warming with Arctic and Subarctic palaeoclimatic records suggests that anticipated future warming will be unprecedented compared to earlier Holocene warming including the Holocene Thermal Maximum (HTM) and subsequent Medieval Warm Period (MWP). Annual warming and winter warming will likely be greater than during earlier periods in the Holocene, but summer temperatures projected by FAR may approximate or not far exceed the summer warming of the HTM. The geographically synchronous pattern of 21st‐century warming projected by FAR will differ from the observed geographic variability in the timing of the HTM, particularly in the western Arctic. Further palaeo‐record syntheses are required to fully delineate the similarities and differences between the HTM and the projected conditions of the 21st century. In addition, palaeo‐records suggest that the Arctic and Subarctic climate may be sensitive to relatively small changes in solar irradiance and understanding the potential effects of natural variations in irradiance on the future climate of the Arctic and Subarctic remains a question deserving further research. FAR mapped estimates of a significant northward displacement of boreal forest and woodland due to warming imply that boreal forest or woodland will displace tundra as far north as the Arctic coastline by AD 2100. In Eurasia the estimated AD 2100 location of the tree line appears to approximate the HTM location. In North America an advance of forest to the coastline on the north slope of Alaska, central Canada and northern Quebec would far outdistance the relatively limited northward advances of boreal forest during the HTM. However, rates of tree species advance and subsequent forest development based on palaeo‐records and currently observed tree line advances raise questions about the likelihood that northward migration and subsequent increases in the population sizes of boreal tree species could occur rapidly enough to establish continuous forest and woodland as far north as the Arctic coastlines of Eurasia and North America by AD 2100. Determining potential rates of northward advance of the northern forests requires further ecological and palaeoecological investigations. Copyright © 2009 John Wiley & Sons, Ltd.
Measurement of the absolute Raman scattering cross section of the 1584‐cm−1 band of benzenethiol and the surface‐enhanced Raman scattering cross section enhancement factor for femtosecond laser‐nanostructured substrates
Authors: Aggarwal R. L. , Farrar L. W. , Diebold E. D. , Polla D. L.
Published: August 2009

The absolute Raman scattering cross section (σRS) for the 1584‐cm−1 band of benzenethiol at 897 nm (1.383 eV) has been measured to be 8.9 ± 1.8 × 10−30 cm2 using a 785‐nm pump laser. A temperature‐controlled, small‐cavity blackbody source was used to calibrate the signal output of the Raman spectrometer. We also measured the absolute surface‐enhanced Raman scattering cross section (σSERS) of benzenethiol adsorbed onto a silver‐coated, femtosecond laser‐nanostructured substrate. Using the measured values of 8.9 ± 1.8 × 10−30 and 6.6 ± 1.3 × 10−24 cm2 for σRS and σSERS respectively, we calculate an average cross‐section enhancement factor (EF) of 0.8 ± 0.3 × 106. Copyright © 2009 John Wiley & Sons, Ltd.
Seeking the perfect customer experience: a case study of British Telecom
Authors: Ojiako Udechukwu , Maguire Stuart
Published: August 2009

In order to construct an understanding of best practices in customer‐focused change, this study investigates how customer‐oriented strategies facilitate the enhancement of service experience.

This paper explores a conceptual strategic approach for the effective delivery of customer‐focused change. This approach is based on principles originating from a case study of a customer experience program instituted by British Telecommunications plc (BT).

There is an urgent need to enhance the experience of UK telecommunications customers, especially as these companies now recognize the relationship between exploitation of core organizational competencies and customer experience enhancement.

This paper has implications for all organizations concerned with the retention of existing customers and the acquisition of new customers in a dynamic business environment.

Copyright © 2009 John Wiley & Sons, Ltd.
Effect of seed moisture content on flaxseed (Linum usitatissimum L.) milling and milled product characteristics
Authors: Schorno Anton L , Manthey Frank A , Hall Clifford A
Published: August 2009

BACKGROUND: Research was conducted to determine the effect of seed moisture content on flaxseed milling and milled product characteristics. Flaxseed with 55, 80, and 105 g kg−1 moisture contents were milled on a centrifugal cutting mill (CCM) configured with a 0.475 and 9.5 kg min−1 feed rate; a hammer mill configured with a blunt hammer face, 0.35 kg min−1 feed rate, 3.1 mm screen, and 2,795 m min−1 hammer tip speed; and a hammer mill configured with a sharp hammer face, 0.35 kg min−1 feed rate, 2.7 mm screen, and 3,870 m min−1 hammer tip speed.

RESULTS: Fine‐particle fraction (≤600 µm) yield was greater from flaxseed with 55 than with 105 g kg−1 moisture content. Surface lipid content correlated positively with fine‐particle yield (r = 0.82, P = 0.01). At each moisture level, the surface lipid extracted from the fine‐particle fraction was greater with 9.5 than 0.475 kg min−1 configuration of CCM and tended to be greater with the blunt than with the sharp hammer configuration of the hammer mill.

CONCLUSION: Results indicated that flaxseed was more difficult to mill to a fine particle size at high than at low moisture content regardless of the mill configuration. Enhanced lipid oxidation was not detected in freshly milled flaxseed. Copyright © 2009 Society of Chemical Industry
Amphiphilic Polymer Nanoparticles: Characterization and Assessment as New Drug Carriers
Authors: Dutta Pranabesh , Shrivastava Saurabh , Dey Joykrishna
Published: August 2009

An amino‐acid‐based hydrophobically modified biocompatible copolymer, poly[(sodium N‐acryloyl‐L‐valinate)‐co‐(N‐octylacrylamide)] was synthesized and characterized. Techniques such as fluorescence probes, DLS, and TEM were used to investigate its aggregation behavior in aqueous solution. The copolymer was observed to form micellar aggregates having diameters in the nanometer range in aqueous solution (pH = 8) through inter‐chain hydrophobic association. This behavior was found to be similar to that of poly[(sodium N‐acryloyl‐L‐valinate)‐co‐(N‐dodecylacrylamide)]. The compact micellar nanostructures were observed to be stable with respect to changes of pH and temperature. The encapsulation and release of griseofulvin, a hydrophobic model drug, was studied.

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Spontaneous Deposition of FITC‐Labeled Dextran into Covalently Assembled (PGMA/PAH)4 Microcapsules
Authors: Feng Zhiqiang , Gao Changyou , Shen Jiacong
Published: August 2009

Spontaneous deposition of fluorescein isothiocyanate labeled dextran (FITC‐dextran) in covalently assembled poly(glycidyl methylacrylate) (PGMA)/poly(allylamine hydrochloride) (PAH) microcapsules was studied and its mechanism was proposed. Incubation of the microcapsules in the FITC‐dextran solution resulted in strong fluorescence emission from the capsule interiors. The deposition was found to be molecular weight ($\overline M _{\rm w}$) dependent and the number of capsules filled with FITC‐dextran was increased along with the $\overline M _{\rm w}$ of FITC‐dextran. Furthermore, the correlation between the deposited substances and the charged species in the capsules was explored quantitatively through UV–Vis and fluorescence spectroscopy.

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Synthesis of Photoisomerizable Block Copolymers by Atom Transfer Radical Polymerization
Authors: Huang Chih‐Feng , Chen Wei , Russell Thomas P. , Balazs Anna C. , Chang Feng‐Chih , Matyjaszewski Krzysztof
Published: August 2009

A series of polystyrene‐block‐poly(n‐butyl methacrylate) (PS‐b‐PnBMA) diblock copolymers (di‐BCPs) with an azobenzene moiety [trans‐4‐methacryloyloxyazobenzene (MOAB)] in the PnBMA segment was prepared by atom transfer radical polymerization (ATRP). P(nBMA‐co‐MOAB) macroinitiators were prepared by activators regenerated by electron transfer (ARGET) ATRP. The MOAB was slightly more reactive than nBMA, resulting in a weak gradient fashion of copolymer. The macroinitiators were subsequently chain‐extended with styrene. Acceleration of the ATRP rate was observed in the presence of a reducing agent. P(nBMA‐co‐MOAB)‐b‐PS di‐BCPs were obtained with relatively narrow molecular weight distributions ($\overline M _{\rm w}$/$\overline M _{\rm n}$ = 1.16–1.49) and the molecular weights were in good agreement with the theoretical values. The efficiency of photoisomerization of the MOAB units was above 80%. DSC traces showed a single Tg suggesting the block copolymers were miscible before UV irradiation. After UV irradiation, the X‐ray reflectivity measurements showed the beating of two frequencies, indicating the formation of island‐hole structure.

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Preparation of a Poly(furfuryl alcohol)‐Coated Highly Porous Polystyrene Matrix
Authors: Lépine Olivier , Birot Marc , Deleuze Hervé
Published: August 2009

Highly porous PS/DVB monoliths were prepared by polymerisation of the continuous phase of a high internal phase emulsion. To improve the mechanical properties of these brittle materials, the monoliths were placed in the presence of FA vapours and the adsorbed monomer was polymerised by heating to create a coating onto the matrix surface. The influence of the coating on the material porous structure was investigated by SEM, mercury intrusion porosimetry and nitrogen adsorption/desorption analyses. The progressive increase in PFA content induced a porosity decrease and a modification of the pore distribution. The more pronounced effect of the coating was the remarkable improvement in the material mechanical properties.

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Well‐Controlled Microcellular Biodegradable PLA/Silk Composite Foams Using Supercritical CO2
Authors: Kang Dong Jin , Xu Deng , Zhang Zhen Xiu , Pal Kaushik , Bang Dae Suk , Kim Jin Kuk
Published: August 2009

PLA biodegradable composites reinforced with various silk fibroin powder contents (0, 1, 3, 5 and 7 wt.‐%) were prepared by solution processing technique using CH2Cl2 as solvent. After that the composites and virgin PLA were foamed by using supercritical CO2. The influence of silk contents on PLA/silk fibroin powder composite foams were investigated by using SEM, XRD and DSC. Compared with PLA foam, the composite foams exhibited a reduction in cell size and increase in cell density at high silk content. With an increase in saturation temperature and pressure, the cell size was increasing and both the cell density and foam density were decreased simultaneously.

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Synthesis and Characterization of Novel Polyurethane Composites Based on Hybrid Inorganic/Organic Phosphazene‐Containing Microspheres
Authors: Zhou Yubo , Huang Xiaobin , Kang Xiaoqi , Fu Jianwei , Zhu Yan , Tang Xiaozhen
Published: August 2009

Novel polyurethane (PU) composites were prepared, based on hybrid inorganic/organic phosphazene‐containing microspheres. The FT‐IR spectra have shown that the microspheres have been linked with PU matrix. The microstructure of the composites is investigated by SEM. In comparison with PU, the glass transition temperatures and thermal stability of the composites are increased. The results from tensile testing of the composites have indicated that tensile strength is improved and elongation at break is almost invariable. The investigation on the surface properties of the composites showed that the water contact angles are obviously increased by adding 2 and 4 wt.‐% microspheres to the matrix.

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Metal‐Free Activation in the Anionic Ring‐Opening Polymerization of Cyclopropane Derivatives
Authors: Illy Nicolas , Boileau Sylvie , Penelle Jacques , Barbier Valessa
Published: August 2009

The successful activation observed when using ButP4 phosphazene base and thiophenol or bisthiols for the anionic ring opening polymerization (ROP) of di‐n‐propyl cyclopropane‐1,1‐dicarboxylate is described. Well‐defined monofunctional or difunctional polymers with a very narrow molecular weight distribution were obtained through a living process. Quantitative end‐capping of the propagating malonate carbanion was accessible by using either an electrophilic reagent such as allyl bromide or a strong acid such as HCl. Kinetics studies demonstrated a much higher reactivity compared to the conventional route using alkali metal thiophenolates.

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Development and application of novel ring‐opening polymerizations to functional networked polymers
Authors: Endo Takeshi , Sudo Atsushi
Published: August 2009

This Highlight gives an overview of the recent progress in development of new ring‐opening polymerizations (ROPs) and their applications to functional networked polymers in our group. The described ROPs involve thermally induced polymerization of 1,3‐benzoxazine, anionic alternating copolymerizations of epoxides and lactones, and those exhibiting equilibrium nature. These ROPs were successfully applied to the syntheses of the relevant networked polymers, leading to their distinctive features such as high thermal stability, small volume shrinkage, and selective decrosslinking ability, which enabled design and development of next generation materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4847–4858, 2009
Study of Inductive Coupled Hydrogen and Argon Plasma Interaction with SiO2 Glass
Authors: Skudra Atis , Revalde Gita , Gavare Zanda , Zorina Natalia
Published: August 2009

This work is devoted to the diagnostics of interaction between hydrogen and argon with the surface of SiO2 glass walls. For diagnostics of the interaction, special high‐frequency electrodeless light sources were prepared, filled with pure argon of 1 Torr or argon‐hydrogen of total pressure of 1 Torr (Ar/H2 mixing ratio is 9:1). Besides the mostly used spherical and cylindrical lamps, dumbbell type lamps have also been investigated. The spectroscopic and AFM measurements showed that in comparison with pure argon plasma, the argon‐hydrogen plasma causes non‐uniform changes of the SiO2 surface. For these modifications active OH are primarily responsible molecules, created in the reactions of hydrogen molecules with oxygen molecules, adsorbed from the walls.
Properties of ta‐C Films for Tools and Machinery Parts
Authors: Präßler Frank , Grimm Werner , Chudoba Thomas
Published: August 2009

The pulsed vacuum arc discharge is an effective technology for the deposition of ta‐C coatings on tools and machinery parts. The properties of these carbon coatings differ substantially from conventional hard nitride films particularly with regard to hardness and wear‐resistance. The paper shows analytical results of ta‐C films in comparison to such hard coatings. Thereby different methods are applied for determination of adhesion, friction, wear‐resistance, and indentation hardness. A simple correlation was found between indentation hardness and wear‐resistance over a wide range of hard materials. Furthermore, all investigated films have a strong adhesion on steel in conventional Rockwell tests. But in scratch tests with increasing normal forces brittle ta‐C films delaminate at lower forces from the surface compared to nitride coatings.
Gas Phase Modification of Superhard Carbon Coatings Deposited by Pulsed DC‐Arc‐Process
Authors: Grimm Werner , Weihnacht Volker
Published: August 2009

The pulsed vacuum arc discharge (pulsed arc) is the most efficient PVD technology for deposition of hard amorphous carbon coatings on tools and machinery parts. Due to the pulsed arc discharge a stable evaporation process and the efficient deposition of hydrogen‐free a‐C type coatings is possible. This paper shows that the pulsed arc enables the deposition of ta‐C and modified a‐C coatings with interesting coating properties in a wide pressure range of argon, acetylene and ammonia gas atmosphere. Coatings with different gas flow rates of these gases were deposited on steel substrates. The coating properties were characterized by using different analytical methods for determination of structure, hardness, friction and wear behaviour. The changes of film properties in dependence of the kind and the rate of gas flow are compared and discussed.
Characterization of a N2/CH4 Microwave Plasma With a Solid Additive Si Source Used for SiCN Deposition
Authors: Bulou Simon , Le Brizoual Laurent , Hugon Robert , De Poucques Ludovic , Belmahi Mohammed , Migeon Henri‐Noël , Bougdira Jamal
Published: August 2009

Microwave plasma assisted chemical vapour deposition of CH4/N2 gas mixture using an additive solid silicon is used to synthesize SiCN. To better understand the mechanisms involved, species such as C, Si, NH, CN, C2 and N2 are observed by means of optical emission spectroscopy. In situ Fourier transform infrared spectroscopy (FTIR) is used as a plasma diagnostic and CH4, NH3, HCN and C2H2 have been detected. Deposits are achieved at various CH4 ratios (1, 4 and 8%) and analysed by means of scanning electron microscopy, energy dispersion X‐ray spectroscopy and FTIR spectroscopy. Adding a silicon source permits to obtain thicker layers confirming the major role of Si in the carbonitride deposition process. Deposits obtained at 8% of CH4 have a composition about 35% of Si, 30% C and 30% N and showed evidence of ternary SiCN system.
Effect of Methane Pressure on the Size of Carbon Nanoparticles Deposited by Pulsed Plasma Enhanced Chemical Vapor Deposition
Authors: Rastkar Ahmad R. , Shokri Babak , Kabir Mojtaba , Amirzadeh Maria , Rahimipour Mohammad R.
Published: August 2009

The nanoparticles of carbon were deposited from methane under the potential of a pulsed direct current discharge. The deposition was carried without external heating. The size, chemistry, and structure of carbon nanoparticles were characterized using transmission electron microscopy (TEM), X‐ray diffraction (XRD), Raman and Fourier transform infrared (FTIR) spectroscopy. The minimum size of the nanoparticles was as low as 10 nm as shown by TEM. The nanocrystalline or amorphous structure of the particles was revealed by XRD. Raman spectroscopy indicated on the sp2 bonds of carbon and FTIR spectroscopy identified the other bonds of carbon.
The protective effect of diabetes mellitus against prostate cancer: Role of sex hormones
Authors: Baradaran N. , Ahmadi H. , Salem S. , Lotfi M. , Jahani Y. , Baradaran N. , Mehrsai A.R. , Pourmand G.
Published: August 2009

BACKGROUND

Diabetes mellitus (DM) has been associated with decreased risk of prostate cancer (PC) in several reports. Hormonal environment of diabetic patients is believed to be an important contributing factor in this regard.

METHODS

Using data from a multi‐center case–control study in Iran, base line testosterone, sex hormone binding globulin (SHBG), estradiol, and albumin levels as well as thorough demographic and medical characteristics of 194 newly diagnosed prostate cancer patients were determined. There were 317 ethnicity‐matched men with no cancer as controls as well. Data was analyzed for hormones of interest in DM patients regarding their cancer status.

RESULTS

Of 511 enrolled patients, twenty‐one cases and 63 controls were diagnosed as DM. Patients with DM were significantly less likely to have PC (OR: 0.44, P = 0.003). Time since DM diagnosis was also inversely correlated with the risk of cancer (P trend < 0.0001). Control patients had significantly higher testosterone, estradiol, and testosterone/SHBG ratio (P < 0.05). As time since DM diagnosis increased by quartiles, testosterone significantly increased (P trend < 0.05). The risk of PC also significantly declined (P trend < 0.0001) following an initial remarkable increase early after DM diagnosis. After including the hormones in the logistic regression model, there was a weak, yet significant inverse association of testosterone/SHBG and DM duration with the risk of PC.

CONCLUSIONS

Based on our results DM duration is inversely correlated with the risk of prostate cancer. Our results do not support the hypothesis that sex hormones, including testosterone, play a major role in the protective effect of DM against PC. Prostate 69: 1744–1750, 2009. © 2009 Wiley‐Liss, Inc.
The expression of androgen‐responsive genes is Up‐Regulated in the epithelia of benign prostatic hyperplasia
Authors: O'Malley Katherine J. , Dhir Rajiv , Nelson Joel B. , Bost James , Lin Yan , Wang Zhou
Published: August 2009

BACKGROUND

Benign prostatic hyperplasia (BPH) is one of the most common diseases among aging men in the United States. In addition to aging, the presence of androgens is another major risk factor in BPH development. However, whether androgen signaling is altered in BPH remains unclear. To determine androgen signaling in BPH, we characterized the expression of four different androgen‐responsive genes, Eaf2/U19, ELL2, FKBP5, and PSA, in BPH and adjacent normal glandular epithelial cells.

METHODS

A set of 17 BPH specimens were resected from patients over 60 years of age with clinical symptoms of BPH. Laser‐capture microdissection (LCM) was used to isolate glandular epithelial cells from BPH areas and adjacent normal areas, separately. LCM isolated cells from individual specimens were lysed and RNA isolation, reverse transcription, and real‐time PCR were performed using CellsDirect™ One‐Step qRT‐PCR Kit (Invitrogen, Carlsbad, CA).

RESULTS

All of the assayed genes displayed increased expression, from ∼2‐ to ∼6‐fold, in BPH as compared to the adjacent normal epithelial cells. We also generated a composite androgen response index based on the expression levels of the four genes, which provides a reliable readout for overall androgen action. Our study showed that the composite androgen response index in BPH is ∼4‐fold as compared to that in the adjacent normal tissues.

CONCLUSIONS

Androgen signaling is significantly elevated in BPH relative to the adjacent normal prostate. Understanding the mechanisms causing elevated androgen signaling may lead to novel approaches for prevention and/or treatment of BPH. Prostate 69: 1716–1723, 2009. © 2009 Wiley‐Liss, Inc.
Dielectric and piezoelectric properties of (Bi0.9Li0.10)(Sc0.90Ta0.10)O3PbTiO3 high‐temperature relaxor piezoelectric ceramics
Authors: Zhao Yi , Jiang Yihang , Zhu Jianguo
Published: August 2009

(1 − x)(Bi0.90Li0.10)(Sc0.90Ta0.10)O3xPbTiO3 (BLSTPTx; x = 0.60–0.65) ceramics were prepared using the conventional mixed oxide method. X‐ray diffraction analysis revealed that BLSTPTx has a pure perovskite structure. In the vicinity of the morphotropic phase boundary, which was observed in the compositional range 0.61 ≤ x ≤ 0.62 from phase structure measurements, the BLSTPTx ceramics showed enhanced piezoelectric properties: piezoelectric constant d33 = 516 pC/N, planar electromechanical coupling factors kp = 57%. The temperature of the permittivity maximum increased with increasing measurement frequency, over the range 302–313 °C, higher than that of conventional relaxor materials such as Pb(B1B2)O3PbTiO3 systems. The ceramics show relaxor ferroelectric features.
Analytic normal forms and symmetries of strict feedforward control systems
Authors: Tall Issa Amadou , Respondek Witold
Published: August 2009

This paper deals with the problem of convergence of normal forms of control systems. We identify ann‐dimensional subclass of control systems, calledspecial strict feedforward form, shortly (SSFF), possessing a normal form which is a smooth (resp. analytic) counterpart of the formal normal form of Kang. We provide a constructive algorithm and illustrate by several examples including the Kapitsa pendulum and the cart–pole system. The second part of the paper is concerned about symmetries of single‐input control systems. We show that any symmetry of a smooth system in SSFF is conjugated to ascaling translationand any 1‐parameter family of symmetries is conjugated to a family of scaling translations along the first variable. We compute explicitly those symmetries by finding the conjugating diffeomorphism. We illustrate our results by computing the symmetries of the cart–pole system. Copyright © 2009 John Wiley & Sons, Ltd.
Gene expression associations with the growth inhibitory effects of small molecules on live cells: Specificity of effects and uniformity of mechanisms
Authors: Shedden Kerby , Yang Yang , Rosania Gus
Published: August 2009

The NCI60 human tumor cell line screen is a public resource for studying selective and nonselective growth inhibition of small molecules against cancer cells. By coupling growth inhibition screening data with biological characterizations of the different cell lines, it becomes possible to infer mechanisms of action underlying some of the observable patterns of selective activity. Using these data, mechanistic relationships have been identified including specific associations between single genes and small families of closely related compounds, and less specific relationships between biological processes involving several cooperating genes and broader families of compounds. Here, we aim to characterize the degree to which such specific and general relationships are present in these data. A related question is whether genes tend to act with a uniform mechanism for all associated compounds, or whether multiple mechanisms are commonly involved. We address these two issues in a statistical framework placing special emphasis on the effects of measurement error in the gene expression and chemical screening data. We find that as measurement accuracy increases, the pattern of apparent associations shifts from one dominated by isolated gene/compound pairs, to one in which families consisting of an average of 25 compounds are associated to the same gene. At the same time, the number of genes that appear to play a role in influencing compound activities decreases. For less than half of the genes, the presence of both positive and negative correlations indicates pleiotropic associations with molecules via different mechanisms of action. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 175–185, 2009