bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment and survival outcomes in young men diagnosed with prostate cancer
Authors: Lin Daniel W. , Porter Michael , Montgomery Bruce
Published: May 2009

BACKGROUND:

Outcomes of treatment for young men compared with older men with prostate cancer are poorly defined outside of limited institutional series. In this study, the authors examined the association between age at diagnosis and grade, stage, treatment, and survival outcomes in men who were diagnosed during the era of prostate‐specific antigen testing.

METHODS:

The National Cancer Institute's Surveillance, Epidemiology, and End Results database was used to identify men who were diagnosed with prostate cancer between 1988 and 2003. Men ages 35 years to 74 years were stratified by age at diagnosis to examine differences in tumor characteristics, treatment, and survival within each age group.

RESULTS:

In total, 318,774 men ages 35 years to 74 years were identified who had been diagnosed with adenocarcinoma of the prostate between 1988 and 2003. The proportion of men aged ≤55 years at diagnosis increased over the study period from 2.3% between the years 1988 and 1991 to 9% between the years 2000 and 2003, and the median age at diagnosis decreased from 72 years in 1988 to 68 years in 2003. Younger men were diagnosed less frequently with organ‐confined tumors (P < .001) but were less likely to be diagnosed with high‐grade cancer (P < .001). Older men were more likely to receive no local therapy or external beam radiation than young men (P < .001 for trend). Among men who had tumors with a Gleason score between 5 and 7, overall survival was worse with advancing age. However, among all age groups with high grade and stage, the youngest men (ages 35‐44 years) were at the highest risk of all‐cause and cancer‐specific death.

CONCLUSIONS:

Age at diagnosis among men with prostate cancer continued to decline. Younger men were more likely to undergo prostatectomy, have lower grade cancer, and, as a group, to have better overall and equivalent cancer‐specific survival at 10 years compared with older men. Among men with high grade and locally advanced prostate cancer, the youngest men had a particularly poor prognosis compared with older men. Cancer 2009. Published 2009 by the American Cancer Society.
Characteristics and treatment modalities for African American women diagnosed with stage III breast cancer
Authors: Rizzo Monica , Lund Mary Jo , Mosunjac Marina , Bumpers Harvey , Holmes Leslie , O'Regan Ruth , Brawley Otis W. , Gabram Sheryl
Published: May 2009

BACKGROUND:

Stage III breast cancers account for about 6% to 7% of all invasive breast cancers diagnosed annually in the United States. In African American (AA) women, the incidence of stage III breast cancers is almost double that in Caucasian women. The aim of this study was to correlate age, receptor status, nuclear grade, and differences in treatment modalities for stage III breast cancer in an inner‐city hospital serving a large AA population.

METHODS:

A retrospective review was performed for all stage III primary breast cancers diagnosed and or treated from 2000 to 2006.

RESULTS:

Of 840 primary invasive breast cancers, the authors identified 107 as stage III, 40.2% IIIA, 32.7% IIIB, 16.8% T4D, and 10.3% IIIC. The majority of the patients were AA (n = 93, 86.9%). Stage IIIC patients were younger (P < .05). Triple negative tumors (TNT) accounted for 29.0%. TNT were more likely among the inflammatory breast cancers (50.0%) compared with the other 3 groups (P < .05). Twenty‐two patients (20.5%) refused chemotherapy, and 24 of the 91 patients (26.3%) who should have received chest wall radiation refused. There was no difference in race, marital status, religion, or age in the patients that refused chemotherapy or radiation therapy versus the majority of patients in this series who received standard care.

CONCLUSIONS:

Stage III breast cancers in AA women have distinct clinical characteristics. A high number of these patients refused chemotherapy and radiation therapy. Reasons for refusal need to be better defined so strategies can be implemented to improve compliance for these advanced stage patients. Cancer 2009. © 2009 American Cancer Society.
Mobile gSET—secure business workflows for Mobile‐Grid clients
Authors: Mangler J. , Witzany C. , Jorns O. , Schikuta E. , Wanek H. , Ul Haq I.
Published: May 2009

Until now, the research community mainly focused on the technical aspects of Grid computing and neglected commercial issues. However, recently the community tends to accept that the success of the Grid is crucially based on commercial exploitation. In our vision Foster's and Kesselman's statement ‘The Grid is all about sharing.’ has to be extended by ‘… and making money out of it!’. To allow for the realization of this vision, the trustworthiness of the underlying technology needs to be ensured. This can be achieved by the use of Gridified Secure Electronic Transaction as a basic technology for trust management and secure accounting in the presented grid‐based workflow. We present a framework, conceptually and technically, from the area of the Mobile‐Grid, which justifies the Grid infrastructure as a viable platform to enable commercially successful business workflows. Copyright © 2009 John Wiley & Sons, Ltd.
Fluorophores as Optical Sensors for Local Forces
Authors: Marawske Stefan , Dörr Denis , Schmitz Daniel , Koslowski Axel , Lu You , Ritter Helmut , Thiel Walter , Seidel Claus A. M. , Kühnemuth Ralf
Published: May 2009

The main aim of this study is to investigate correlations between the impact of an external mechanical force on the molecular framework of fluorophores and the resultant changes in their fluorescence properties. Taking into account previous theoretical studies, we designed a suitable custom‐tailored oligoparaphenylenevinylene derivative (OPV5) with a twisted molecular backbone. Thin foils made of PVC doped with 100 nM OPV were prepared. By applying uniaxial force, the foils were stretched and three major optical effects were observed simultaneously. First, the fluorescence anisotropy increased, which indicates a reorientation of the fluorophores within the matrix. Second, the fluorescence lifetime decreased by approximately 2.5 % (25 ps). Finally, we observed an increase in the emission energy of about 0.2 % (corresponding to a blue‐shift of 1.2 nm). In addition, analogous measurements with Rhodamine 123 as an inert reference dye showed only minor effects, which can be attributed to matrix effects due to refractive index changes. To relate the observed spectroscopic changes to the underlying changes in molecular properties, quantum‐chemical calculations were also performed. Semiempirical methods had to be used because of the size of the OPV5 chromophore. Two conformers of OPV5 (C2 and Ci symmetry) were considered and both gave very similar results. Both the observed blue‐shift of fluorescence and the reduced lifetime of OPV5 under tensile stress are consistent with the results of the semiempirical calculations. Our study proves the feasibility of fluorescence‐based local force probes for polymers under tension. Improved optical sensors of this type should in principle be able to monitor local mechanical stress in transparent samples down to the single‐molecule level, which harbors promising applications in polymer science and nanotechnology.
Cover Picture: Tuning the Rates of Long‐Range Charge Transfer across Phenylene Wires (ChemPhysChem 8/2009)
Authors: Walther Mathieu E. , Wenger Oliver S.
Published: May 2009

The central part of the cover picture shows that the rates for long‐range charge transfer across covalent phenylene bridges can be very sensitive to the chemical substituents attached to the individual bridging units. The peripheral parts of the picture illustrate the flash–quench technique employed to investigate intramolecular charge transfer between a phenothiazine donor and a photochemically generated ruthenium(III) complex. On page 1203, M. E. Walther and O. S. Wenger explain their experimental findings in terms of donor‐bridge energy matching for hole transfer.

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Sensitivity improvement of the receiver module in the passive tag‐based RFID reader
Authors: Chun Jonghun , Rhee Seunghak , Kang Gwangwon , Moon Yongseon , Park Jongan
Published: May 2009

In this paper, we have designed an RFID reader receiver system for improving the performance of the passive Tag‐based 908.5–914 MHz RFID reader, and analyzed the system performance vis‐à‐vis frequency, reader, and tag properties. The commercial receiver system causes a loss in sensitivity because of its 24 capacitors and six inductors. To improve the overall sensitivity of the receiver, we have designed a system using a circulator, low noise amplifier (LNA) and a SAW filter. The experimental results show that the use of a circulator to separate the Tx/Rx paths eliminates interference, the LNA improves the sensitivity of the Rx module and SAW filter eliminates the noise and spurious components in the received signal. Copyright © 2009 John Wiley & Sons, Ltd.
Examining processes or/and outcomes? Evaluation concepts in European governance of natural resources
Authors: Rauschmayer Felix , Berghöfer Augustin , Omann Ines , Zikos Dimitrios
Published: May 2009

Effectively evaluating the governance of natural resources is a precondition for its improvement in contexts of change. In order to do so, one can use methods for evaluating (1) the outcome of a governance process or (2) the governance process itself. Outcome‐oriented and process‐oriented approaches have different strengths and weaknesses. This paper explores the challenges associated with both options when applied to European biodiversity and water governance – namely the implementation of the Habitats Directive (Natura 2000 network) and the Water Framework Directive.

Current evaluation practice, concerned with governance processes for EU policy implementation, focuses mainly on outcomes. In this paper, we examine the methodology involved and argue that, for three reasons, it makes sense to combine the two approaches: a normative reason, relating to standards of good governance; a substantive reason, relating to the complexity of the system to be governed; and a third, instrumental, reason relating to the task of policy evaluation and implementation itself. Combining outcome‐ and process‐oriented evaluation of governance processes is not without caveats, but it appears a promising approach in the light of current problems in European governance of natural resources. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Inclusive risk governance: concepts and application to environmental policy making
Authors: Renn Ortwin , Schweizer Pia‐Johanna
Published: May 2009

The concept of inclusive risk governance is based on a normative belief that the integration of knowledge and values can best be accomplished by involving those actors in the decision‐making process that are able to contribute all the respective knowledge as well as the variability of values necessary to make effective, efficient, fair and morally acceptable decisions about risk. In the risk arena the major actors are governments, the economic sector, scientific communities and representatives of civil society. The paper addresses the conceptual issues of how to integrate the contributions of the different actor groups in risk governance. Who and what is or should be included in the deliberations, and how is closure accomplished or reached in such settings? The main thesis in the paper is that these two questions can only be answered in the context of six underlying concepts of deliberation in democratic societies. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
The Variable Binding Modes of Phenylbis(pyrid‐2‐ylmethyl)phosphane and Bis(pyrid‐2‐ylmethyl) Phenylphosphonite with AgI and CuI
Authors: Hung‐Low Fernando , Renz Amanda , Klausmeyer Kevin K.
Published: May 2009

A series of new bridging phosphane and phosphonite structures forming three‐ and six‐membered rings with the metal centers were synthesized and characterized. The resulting compounds of phenylbis(pyrid‐2‐ylmethyl)phosphane (1) with the silver(I) salts of trifluoroacetate (tfa–), tetrafluoroborate (BF4–), and trifluoromethanesulfonate (OTf–), and copper tetrakis(acetonitrile) hexafluorophosphate (PF6–) shows the flexibility of the ligand by displaying different coordination modes associated with the electronic and structural characteristics of the corresponding anion. Accordingly, ligand 1 in these complexes displays two different binding modes. With Agtfa and AgBF4 compounds 3 and 4 are obtained where the ligand chelates to two silver atoms that exhibit normalAg–Ag contacts in the range of 2.9 Å. When AgOTf or Cu(NCCH3)4PF6 are used, one molecule of 1 bridges the metal centers through a phosphorus atom while another is terminally bound. This induces short M–M distances of 2.6871 and 2.568 Å for 5 and 6, respectively. Similarly, the coordination behavior of the heterofunctional bis(pyrid‐2‐ylmethyl) phenylphosphonite ligand (2) is reported with Cu(NCCH3)4PF6 (7) and AgBF4 (8) to form two novel discrete molecules. In these complexes 2 coordinates through the P and N atoms, with the difference that in 7 the O atom of one of the carbinol arms is also bound to the Cu. Elemental analysis, variable‐temperature multinuclear NMR spectroscopy, single‐crystal X‐ray diffraction, and low‐temperature luminescence studies were carried out to fully characterize the compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Electron Transfer Processes at Aryl‐Modified Glassy Carbon Electrode
Authors: Schauff Siri , Ciorca Mircea , Laforgue Alexis , Bélanger Daniel
Published: May 2009

The effect of a layer of electrochemically grafted 4‐diazo‐N,N‐diethylaniline (DEA) groups on the electron transfer kinetics of redox systems, displaying fast and slow heterogeneous electron transfer rate constants at edge and basal planes of carbon, was investigated. The properties of the modified electrode were characterized by cyclic voltammetry using four different inorganic redox systems (Fe(CN)$\rm{ {_{6}^{3-/4-}}}$, Co(phen)$\rm{ {_{3}^{2+/3+}}}$, Ru(NH3)$\rm{ {_{6}^{2+/3+}}}$, and IrCl$\rm{ {_{6}^{2-/3-}})}$ in acidic, neutral, and basic media. Two distinct blocking behaviors and electrostatic effects were observed. More precisely, a strong blocking effect of the grafted layer on Fe(CN)$\rm{ {_{6}^{3-/4-}}}$ and Co(phen)$\rm{ {_{3}^{2+/3+}}}$ was found, whereas Ru(NH3)$\rm{ {_{6}^{2+/3+}}}$ and IrCl$\rm{ {_{6}^{2-/3-}}}$ showed to be rather unaffected by the presence of the DEA grafted layer.
Radioprotective effects of Daflon against genotoxicity induced by gamma irradiation in human cultured lymphocytes
Authors: Hosseinimehr Seyed Jalal , Ahmadi Amirhossein , Mahmoudzadeh Aziz , Mohamadifar Soheila
Published: May 2009

The ability of Daflon to protect against genotoxicity induced by gamma irradiation has been investigated in vivo and in vitro in cultured lymphocytes from healthy human volunteers. Peripheral human blood samples were collected predose (10 min before) and 1, 2, and 3 hr after a single oral ingestion of 1000 mg of Daflon. At each time point, whole blood was exposed in vitro to 150 cGy of cobalt‐60 gamma rays, and then the lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis‐blocked binucleated cells. For each volunteer, the results showed a significant increase in the incidence of micronuclei after exposure to gamma irradiation as compared to control unexposed samples. As early as 1 hr after Daflon administration, a significant decrease in the incidence of micronuclei was observed in comparison with similarly irradiated lymphocytes collected before administration. The maximum protection was reached 1 hr after administration of Daflon with a significant decrease in the frequency of micronuclei of 40%. These findings suggest the possible application of Daflon for the protection of human lymphocytes from the genetic damage and side effects induced by gamma irradiation. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.
Simple formulas for the dynamic stiffness of pile groups
Authors: Taherzadeh Reza , Clouteau Didier , Cottereau Régis
Published: May 2009

Simple formulas are derived for the dynamic stiffness of pile group foundations subjected to horizontal and rocking dynamic loads. The formulations are based on the construction of a general model of impedance matrices as the condensation of matrices of mass, damping, and stiffness, and on the identification of the values of these matrices on an extensive database of numerical experiments computed using coupled finite element–boundary element models. The formulations obtained can be readily used for the design of both floating piles on homogeneous half‐space and end‐bearing piles and are applicable for a wide range of mechanical and geometrical parameters of the soil and piles, in particular for large pile groups. For the seismic design of a building, the use of the simple formulas rather than a full computational model is shown to induce little error on the evaluation of the response spectra and time histories. Copyright © 2009 John Wiley & Sons, Ltd.
Sediment transport due to tree root throw: integrating tree population dynamics, wildfire and geomorphic response
Authors: Gallaway J. M. , Martin Y. E. , Johnson E. A.
Published: May 2009

A field study was conducted to analyze root throw and associated sediment transport in Hawk Creek Watershed, Canadian Rockies. A large crown fire in 2003 allowed the opportunity to study pre‐fire and post‐fire root throw. Based on field data, a significant relation was found between gradient and root plate volume, as well as individual root plate dimensions. Given that tree diameters increase as trees age and that a relation in the field data was found between tree diameter and root plate volumes, sediment transport due to root throw is expected to change in response to forest disturbance and stand age. Sediment disturbance, which is the amount of sediment upheaved during tree topple and does not take into account transport distance, shows higher values on steeper gradients. Sediment transport was notable for the steepest plots, with pre‐fire values of 0·016 cm3 cm–1 a–1and post‐fire values of 0·18 cm3 cm–1 a–1. A tree population dynamics model is then integrated with a root throw transport model calibrated for the Canadian Rockies to examine the temporal dynamics of sediment transport. Fire is incorporated as a disturbance that initiates development of a new forest, with the model cycling through generations of forest. Trees fall according to an exponential rate that is based on time since death, resulting in a time lag between tree mortality and sediment transport. When values of time‐since‐previous‐fire are short, trees are generally <13 cm, and minimal sediment is upheaved during toppling. If trees reach a critical diameter at breast height (dbh) at time of fire, a pulse of sediment occurs in the immediate post‐fire years due to falling of killed trees, with tree fall rates decreasing exponentially with time‐since‐fire. A second pulse of root throw begins at about 50 years after the previous fire, once new recruits reach a critical dbh and with initiation of competition‐induced mortality. Copyright © 2009 John Wiley & Sons, Ltd.
Electrochemical Evaluation of Porous Non‐Platinum Oxygen Reduction Catalysts for Polymer Electrolyte Fuel Cells
Authors: Olson T. S. , Blizanac B. , Piela B. , Davey J. R. , Zelenay P. , Atanassov P.
Published: May 2009

A porous non‐platinum electrocatalyst for the oxygen reduction reaction (ORR), obtained by pyrolysing a cobalt porphyrin precursor, was evaluated by electrochemical means. The reactivity of the non‐platinum ORR catalyst was investigated with a rotating disc electrode (RDE) experimental set up. RDE data were collected in an acidic electrolyte containing N2, O2, CO and under mixed reactant O2/methanol conditions. The electrochemical performance of such‐obtained non‐platinum catalyst is discussed and compared to platinum‐based ORR catalysts. Based on the results collected here, we are able to propose and test possible proton exchange fuel cell (PEFC) operating conditions where non‐platinum ORR catalysts can be utilised. Direct methanol fuel cell (DMFC) data demonstrating a superior performance of the non‐platinum catalyst relative to platinum black, often perceived as the state‐of‐the‐art oxygen–reduction catalyst for the DMFC cathode is presented.
Metal/Ceramic Interface Properties and Their Effects on SOFC Development
Authors: Tietz F. , Nikolopoulos P.
Published: May 2009

Development of solid oxide fuel cells (SOFCs) involves multidisciplinary research, which needs input from many directions. As an example, this contribution describes the influence of basic metallurgical experiments on the selection or the modification of specific materials used in SOFCs. Wettability studies, although typically regarded as model experiments, give clear indications of the combinations of materials, which show better compatibility and might be more successfully integrated in SOFC designs, especially when metal/ceramic interfaces are involved. Various material combinations, i.e. anode cermets, glass/steel and ceramic/silver/steel compounds, are discussed in more detail showing the impact of fundamental studies on the SOFC development actually applied. This work gives a short overview on the basic aspects of selected material combinations.
Preparation and Properties of Cross‐linked Sulphonated Poly(sulphide sulphone) Membranes for Fuel Cell Applications
Authors: Xu N. , Guo X. , Fang J. , Yin J. , Yuan M. , Chen B.
Published: May 2009

A series of cross‐linked sulphonated poly(sulphide sulphone) (SPSSF) membranes have been prepared via a polyphosphoric‐acid‐catalysed condensation reaction at 180 °C for a period of time (1.5–5.0 h) and the resulting cross‐linking bonds are the highly stable sulphonyl groups. The cross‐linking density could be controlled by regulating the reaction time. Cross‐linking caused significant enhancement in the mechanical properties and large reduction in both water uptake (WU) and methanol permeability. The SPSSF‐60 membrane (the numeral 60 refers to the degree of sulphonation), e.g. had a tensile strength increased from 16 to 27 MPa (wet membranes) after cross‐linking for 5 h, while the WU substantially decreased from 320 to 58 wt.‐% and the methanol permeability decreased from 1.9 × 10–6 to 2.7 × 10–7 cm2 s–1 (30 °C). Single cell test on hydrogen/oxygen revealed that the cross‐linked SPSSF‐50 (1.5 h) membrane displayed higher open circuit voltage (OCV, 1.02 V), higher maximum output power density (1.32 W cm–2) and significantly slower OCV decay rate than the uncross‐linked SPSSF‐40 membrane under the same operating conditions despite their similar ion exchange capacities. The cross‐linked SPSSF‐60 (5.0 h) and SPSSF‐50 (1.5 h) membranes showed significantly better fuel cell performance than Nafion 212.
A Novel Cell‐Array Design for Single Chamber SOFC Microstack
Authors: Liu Mingliang , Lü Zhe , Wei Bo , Huang Xiqiang , Chen Kongfa , Su Wenhui
Published: May 2009

A novel design of single chamber solid oxide fuel cell (SC‐SOFC) microstack with cell‐array arrangement is fabricated and operated successfully in a methane–oxygen–nitrogen mixture. The small stack, consisting of five anode‐supported single cells connected in series, exhibits an open circuit voltage (OCV) of 4.74 V at the furnace temperature of 600 °C and a maximum power output of 420 mW (total active electrode area is 1.4 cm2) at the furnace temperature of 700 °C. A gas mixture of CH4/O2 = 1 leads to best performance and stability.
Detecting the effects of spatial variability of rainfall on hydrological modelling within an uncertainty analysis framework
Authors: Younger P. M. , Freer J. E. , Beven K. J.
Published: May 2009

Spatial patterns of rainfall are known to cause differences in observed flow. In this paper, the effects of perturbations in rainfall patterns on changes in parameter sets as well as model output are explored using the hydrological model Dynamic TOPMODEL for the Brue catchment (135 km2) in southwest England. Overall rainfall amount remains the same at each time step so the perturbations act as effectively treated errors in the spatial pattern. The errors were analysed with particular emphasis on when they could be detected under an uncertainty framework.

Higher rainfall perturbations (multipliers of × 4 and greater) in the low lying and high areas of the catchment resulted in changes to event peaks and accompanying compensation in the baseflow. More significantly, changes in the effective model parameter values required by the best models to take account of the more extreme patterns were able to be detected by noting when distributions of parameters change under uncertainty. Copyright © 2009 John Wiley & Sons, Ltd.
Eradication of Helicobacter pylori prevents cancer development in subjects with mild gastric atrophy identified by serum pepsinogen levels
Authors: Yanaoka Kimihiko , Oka Masashi , Ohata Hiroshi , Yoshimura Noriko , Deguchi Hisanobu , Mukoubayashi Chizu , Enomoto Shotaro , Inoue Izumi , Iguchi Mikitaka , Maekita Takao , Ueda Kazuki , Utsunomiya Hirotoshi , Tamai Hideyuki , Fujishiro Mitsuhiro , Iwane Masataka , Takeshita Tatsuya , Mohara Osamu , Ichinose Masao
Published: May 2009

A longitudinal cohort study was conducted in Helicobactor pylori‐infected middle‐aged Japanese males to evaluate the preventive effects of H. pylori eradication on the development of gastric cancer according to the extent of chronic atrophic gastritis (CAG). The extent of CAG was monitored by baseline serum pepsinogen (PG) levels. We followed 3,656 subjects with persistent H. pylori infection and 473 subjects with successful H. pylori eradication for cancer development for a mean (SD) of 9.3 (0.7) years. Groups with and without extensive CAG were categorized based on PG test‐positive criteria to detect extensive CAG of PG I ≤ 70 ng/ml and PG I/II ratio ≤ 3.0. During the study period, 5 and 55 gastric cancers developed in H. pylori‐eradicated and the noneradicated subjects, respectively, indicating no significant reduction in cancer incidence after H. pylori eradication. Among the noneradicated subjects, 1,329 were PG test‐positive and 2,327 were PG test‐negative. Gastric cancer was confirmed in 30 and 25 subjects, respectively. Among subjects whose infection was eradicated, 155 were PG test‐positive and 318 were PG test‐negative. Of these subjects, gastric cancer was confirmed in 3 and 2 subjects, respectively. Significant reduction in cancer incidence after eradication was observed only in PG test‐negative subjects (p < 0.05; log‐rank test). The results of this study strongly indicate that cancer development after eradication depends on the presence of extensive CAG before eradication and that H. pylori eradication is beneficial to most PG test‐negative subjects with mild CAG as defined by the aforementioned criteria. © 2009 UICC
Assessment of irrigation water allocation based on optimization and equitable water reduction approaches to reduce agricultural drought losses: The 1999 drought in the Zayandeh RUD irrigation system (IRAN)
Authors: Moghaddasi M. , Morid S. , Araghinejad S. , Alikhani M. Agha
Published: May 2009

Drought is common to Iran and the agricultural sector is its main victim. Reducing demand for irrigation water is considered the best management practice to alleviate losses. An equitable water reduction approach has been traditionally applied in the management of irrigation systems. This research work examines and compares this approach with that based on the optimization method to manage agricultural water demand during drought to minimize damage. To evaluate these methodologies, the 1999 drought in the Zayandeh Rud irrigation system was selected and the required models developed. In the optimization method, crop growth stages and their sensitivity to water stress at different stages are embedded in the calculations. The results show that the optimization method resulted in 42% more income for the agricultural sector using the same amount of water allocated in the 1999 drought. This difference emphasizes the importance of water allocation with respect to growth stages rather than simply cutting allocations on an equitable basis to combat water scarcity. However, managing the system using the optimization method is more complex and requires a new framework and planning to make it operational. Copyright © 2009 John Wiley & Sons, Ltd.
Yield, water use and yield response factor of flue‐cured tobacco under different levels of water supply at various growth stages
Authors: Çakir Recep , Çebi Ulviye
Published: May 2009

The study aiming to determine the effect of different irrigation regimes and water stress imposed at different growth stages on water use and leaf yield of flue‐cured tobacco plant (Nicotiana tabacum L.), was carried out during the period of 2000–03. The field trials were conducted on a silty loam Entisol soil, poor in organic matter and rich in potassium on the fields of the Atatürk Soil and Water Resources Research Institute in Kırklareli. A randomised complete block design with three replications was applied and K‐326 Virginia tobacco cultivar was used in the experiment. Three known stages of the plant, vegetative (V), yield formation (F) and ripening (R), were considered and a total of 14 (including rain‐fed) irrigation treatments were applied. All the experimental treatments were irrigated on the same day in each growth stage with the amount of water required to fill the 0–90 cm soil depth to field capacity, and three levels of water amount reductions (0, 40 and 60%) were applied at each development stage. A single irrigation was applied during the second part of the vegetative stage, while subsequent water applications were at the 50 and 70% depletion level during the yield formation and ripening stages, respectively. Results of the 3‐year study show that either total irrigation water amounts and number of applications, or leaf yields are closely related to precipitation rate and distribution during the growing year. While the seasonal irrigation amounts applied in the adequate irrigation treatment (VFR) were greater (945 and 815 mm respectively in the drier experimental years of 2000 and 2001), they were much lower (587 mm) during the rainy year of 2003. The highest leaf yields in the range of 5170–6050 kg ha−1 were obtained from the fully irrigated programme (VFR), from treatments with 40% reduction in irrigation water amount at any stage (V1FR; VF1R, VFR1) and irrigation programme (FR) including omitted irrigation at vegetative stage and fully irrigated during the next two stages. It was also determined that close linear relationships exist between seasonal evapotranspiration rate and leaf yield, and seasonal evapotranspiration deficit and relative yield reduction, during each of the experimental years. Copyright © 2009 John Wiley & Sons, Ltd.
Role of microRNAs in cardiac hypertrophy and heart failure
Authors: Wang Nan , Zhou Zhen , Liao Xinghua , Zhang Tongcun
Published: May 2009

MicroRNAs (miRNAs) are a class of endogenous, highly conserved, small noncoding RNAs that regulate gene expression post‐transcriptionally. Recent studies have demonstrated that miRNAs are aberrantly expressed in the cardiovascular system. The implications of miRNAs in cardiovascular disease have recently been recognized, representing the most rapidly evolving research field. Gain‐ and loss‐of‐function studies in mice models have identified distinct roles for specific miRNAs during cardiac hypertrophy, heart failing, and myocardial infarction. In the present article, the currently relevant findings on the role of miRNAs in cardiac hypertrophy and heart failure will be summarized and the target genes and signaling pathways linking these miRNAs will be discussed. Furthermore, we focus on the use of miRNA mimics and antagonists (antagomirs) as tools for disease therapy in the cardiovascular system in the future. Taken together, the recent studies showed that miRNAs are key regulators of gene expression in cardiovascular biology and suggested the potential importance of miRNAs as diagnostic markers and therapeutic targets for cardiovascular disease. © 2009 IUBMB IUBMB Life, 61(6): 566–571, 2009
The role of the neutral amino acid transporter B0AT1 (SLC6A19) in Hartnup disorder and protein nutrition
Authors: Bröer Stefan
Published: May 2009

Hartnup disorder (OMIM 234500) is an autosomal recessive disorder, which was first described in 1956 as an aminoaciduria of neutral amino acids accompanied by a variety of symptoms, such as a photo‐sensitive skin‐rash and cerebellar ataxia. The disorder is caused by mutations in the neutral amino acid transporter B0AT1 (SLC6A19)1. To date 21 mutations have been identified in more than twenty families. SLC6A19 requires either collectrin or angiotensin‐converting enzyme 2 for surface expression in the kidney and intestine, respectively. This ties SLC6A19 together with more complex functions such as blood‐pressure control, glomerular structure, and exocytosis. © 2009 IUBMB IUBMB Life, 61(6): 591–599, 2009
p38 Mitogen‐activated protein kinase‐dependent regulation of SRC‐3 and involvement in retinoic acid receptor α signaling in embryonic cortical neurons
Authors: Chai Zhi , Yang Lihong , Yu Baofeng , He Quanren , Li Wan‐I , Zhou Ran , Zhang Ting , Zheng Xiaoying , Xie Jun
Published: May 2009

Appropriate retinoic acid (RA) signaling is essential in the development of the central nervous system (CNS). Previous studies have shown that RA activates p38 mitogen‐activated protein kinase (MAPK) and steroid receptor coactivator (SRC)‐3 in tumor cells in vitro. It is unknown whether the activation of p38 MAPK and SRC‐3 is involved in RA‐mediated CNS development. The current study investigated a possible role for p38 MAPK in the regulation of (SRC)‐3 phosphorylation/degradation and in retinoic acid receptor (RAR)α signaling in mouse fetal cortical neurons treated with all‐trans retinoic acid (ATRA). Results showed that ATRA treatment rapidly activated p38 MAPK, which in turn resulted in phosphorylation with subsequent degradation of SRC‐3. Inhibition of p38 MAPK by SB203580 blocked the phosphorylation and degradation of SRC‐3. The binding of RARα to retinoic acid responsive element (RARE) was rapidly increased in neurons following ATRA treatment. Inhibition of p38 MAPK significantly enhanced the RARα‐RARE binding activity, but had no effects on ATRA‐induced decrease of RARα. Treatment of the fetal cortical neurons with ATRA significantly increased the expression of HOXd3, a retinoid‐target gene. The increase of HOXd3 expression was augmented when p38 MAPK activity was inhibited by a specific inhibitor, SB203580. Results suggest that ATRA activates the p38 MAPK signal pathway with resultant degradation of SRC‐3, and that p38 MAPK is involved in the regulation of RARα‐mediated signaling in developing neurons. © 2009 IUBMB IUBMB Life, 61(6): 670–678, 2009
Unraveling the mysteries of endostatin
Authors: Fu Yan , Tang Huadong , Huang Yujie , Song Nan , Luo Yongzhang
Published: May 2009

Endostatin, a 20‐kDa C‐terminal proteolytic fragment of collagen XVIII, is a specific endogenous angiogenesis inhibitor discovered more than a decade. The structure, stability, and mechanism of actions of endostatin have been extensively investigated during the past 12 years, among which controversial reports remain unclarified. The mysteries include the following: 1) Why controversial efficacies were observed with endostatin regarding tumor inhibition? Particularly, why does an N‐terminal modified endostatin show good clinical responses in China, whereas the clinical trials of the wild type endostatin were terminated at the early stage of phase II in the USA? 2) What is the contribution of zinc‐binding to the stability and biological functions of endostatin? 3) Why does insoluble endostatin shrink tumors? 4) How to ensure that endostatin is correctly refolded? 5) How does endostatin exert its biological functions? Recent progress regarding the biophysical properties, biological functions, signaling pathways, and clinical trials of endostatin are reviewed here. Surprising findings show that the integrity of the N‐terminal sequence, the capability of zinc‐binding, and the correct folding are three essential elements for assurance of structural stability and biological functions of endostatin. This review provides clues to understand the mysteries of endostatin and its derivatives. © 2009 IUBMB IUBMB Life, 61(6): 613–626, 2009
Regulation of DGK‐θ
Authors: Tu‐Sekine Becky , Raben Daniel M.
Published: May 2009

Diacylglycerol kinases are important regulators of lipid signaling and, consequently, important regulators of many diglyceride‐dependent and PA‐dependent proteins. Research over the last twenty years has clearly demonstrated that individual DGK isoforms can be connected with disparate cellular processes, indicating the presence of a sophisticated regulatory network for diglyceride and phosphatidic acid signaling through the regulation of individual DGK isoforms. This review presents the progress on the characterization of a primarily neuronal isoform DGK‐θ, and examines current data on the primary structure, regulation and potential cellular functions of this enzyme. J. Cell. Physiol. 220: 548–552, 2009. © 2009 Wiley‐Liss, Inc.
Molecular characterization of a human cation‐Cl− cotransporter (SLC12A8A, CCC9A) that promotes polyamine and amino acid transport
Authors: Daigle Nikolas D. , Carpentier Gabriel A. , Frenette‐Cotton Rachelle , Simard Michael G. , Lefoll Marie‐Hélène , Noël Micheline , Caron Luc , Noël Josette , Isenring Paul
Published: May 2009

Cation‐Cl− cotransporters (CCCs) belong to a large family of proteins that includes 9 isoforms, two of which have still not been ascribed a transport function (CCC8 and CCC9) while the others are all known to promote Cl−‐coupled Na+ and/or K+ movement at the cell surface. The CCCs are also included in a larger family termed amino acid‐polyamine‐organocation carriers (APCs). In contrast to the CCCs, however, polyamine (PA) transporters have thus far been isolated from unicellular species exclusively and do not all belong to the APC family. In this work, we have found that a splice variant of CCC9 (CCC9a) promotes PA‐amino acid transport at the surface of HEK‐293 cells. We have also found that the influx of PAs in CCC9a‐expressing cells is inhibited by pentamidine as well as furosemide, and that it increases further in the presence of specific amino acids but not of Na+, K+, or Cl−. Hence, a group of substrates that are directly transported by CCC9 and the molecular identity of a PA transport system in animal cells may have been uncovered for the first time. These findings are of special interest given that intracellular PAs play a key role in cell proliferation. J. Cell. Physiol. 220: 680–689, 2009. © 2009 Wiley‐Liss, Inc.
Environmental regulation of notochordal gene expression in nucleus pulposus cells
Authors: Rastogi Anshu , Thakore Pratiksha , Leung Aileen , Benavides Magda , Machado Monica , Morschauser Michael A. , Hsieh Adam H.
Published: May 2009

Cells of the nucleus pulposus (NP) in the intervertebral disc are derived directly from the embryonic notochord. In humans, a shift in NP cell population coincides with the beginning of age‐related changes in the extracellular matrix that can lead to spinal disorders. To begin identifying the bases of these changes, the manner by which relevant environmental factors impact cell function must be understood. This study investigated the roles of biochemical, nutritional, and physical factors in regulating immature NP cells. Specifically, we examined cell morphology, attachment, proliferation, and expression of genes associated with the notochord and immature NP (Sox9, CD24, and type IIA procollagen). Primary cells isolated from rat caudal discs were exposed to different media formulations and physical culture configurations either in 21% (ambient) or 2% (hypoxic) O2. As expected, cells in alginate beads retained a vacuolated morphology similar to chordocytes, with little change in gene expression. Interestingly, NP tissues not enzymatically digested were more profoundly influenced by oxygen. In monolayer, α‐MEM preserved vacuolated morphology, produced the highest efficiency of attachment, and best maintained gene expression. DMEM and Opti‐MEM cultures resulted in high levels of proliferation, but these appeared to involve small non‐vacuolated cells. Gene expression patterns for cells in DMEM monolayer cultures were consistent with chondrocyte de‐differentiation, with the response being delayed by hypoxia. Overall, results indicate that certain environmental conditions induce cellular changes that compromise the notochordal phenotype in immature NP. These results form the foundation on which the mechanisms of such changes can be elucidated. J. Cell. Physiol. 220: 698–705, 2009. © 2009 Wiley‐Liss, Inc.
Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin‐induced barrier breakdown
Authors: Baumer Y. , Spindler V. , Werthmann R.C. , Bünemann M. , Waschke J.
Published: May 2009

Barrier stabilizing effects of cAMP as well as of the small GTPase Rac 1 are well established. Moreover, it is generally believed that permeability‐increasing mediators such as thrombin disrupt endothelial barrier functions primarily via activation of Rho A. In this study, we provide evidence that decrease of both cAMP levels and of Rac 1 activity contribute to thrombin‐mediated barrier breakdown. Treatment of human dermal microvascular endothelial cells (HDMEC) with Rac 1‐inhibitor NSC‐23766 decreased transendothelial electrical resistance (TER) and caused intercellular gap formation. These effects were reversed by addition of forskolin/rolipram (F/R) to increase intracellular cAMP but not by the cAMP analogue 8‐pCPT‐2′‐O‐Methyl‐cAMP (O‐Me‐cAMP) which primarily stimulates protein kinase A (PKA)‐independent signaling via Epac/Rap 1. However, both F/R and O‐Me‐cAMP did not increase TER above control levels in the presence of NSC‐23766 in contrast to experiments without Rac 1 inhibition. Because Rac 1 was required for maintenance of barrier functions as well as for cAMP‐mediated barrier stabilization, we tested the role of Rac 1 and cAMP in thrombin‐induced barrier breakdown. Thrombin‐induced drop of TER and intercellular gap formation were paralleled by a rapid decrease of cAMP as revealed by fluorescence resonance energy transfer (FRET). The efficacy of F/R or O‐Me‐cAMP to block barrier‐destabilizing effects of thrombin was comparable to Y27632‐induced inhibition of Rho kinase but was blunted when Rac 1 was inactivated by NSC‐23766. Taken together, these data indicate that decrease of cAMP and Rac 1 activity may be an important step in inflammatory barrier disruption. J. Cell. Physiol. 220: 716–726, 2009. © 2009 Wiley‐Liss, Inc.
Diffusion‐weighted echo‐planar magnetic resonance imaging for the assessment of tumor cellularity in patients with soft‐tissue sarcomas
Authors: Schnapauff Dirk , Zeile Martin , Niederhagen Manuel Ben , Fleige Barbara , Tunn Per‐Ulf , Hamm Bernd , Dudeck Oliver
Published: May 2009

Purpose

To investigate the eligibility of diffusion‐weighted imaging (DWI) for the evaluation of tumor cellularity in patients with soft‐tissue sarcomas.

Materials and Methods

Thirty consecutive patients with a total of 31 histologically‐proven soft‐tissue sarcomas prospectively underwent magnetic resonance imaging (MRI) including DWI with echo‐planar imaging (EPI) technique immediately before open biopsy (N = 1) or tumor resection (N = 30). Fourteen patients had no previous anticancer treatment, 16 had received neoadjuvant therapy. Tumor cellularity as determined from histological sections was compared with minimum apparent diffusion coefficient (ADC).

Results

Tumor cellularity correlated well with minimum ADC in a linear fashion, with a Pearson correlation coefficient of –0.88 (95% confidence interval [CI]: –0.75 to –0.96). This relationship was not influenced by prior anticancer treatment. There was only a tendency toward lower ADC in tumor with higher grading but no significant dependency (P = 0.08).

Conclusion

DWI has proven useful for the assessment of tumor cellularity in soft‐tissue sarcomas. In result, DWI may be used as a powerful noninvasive tool to monitor responses of cytotoxic treatment as reflected by changes in tumor cellularity. J. Magn. Reson. Imaging 2009. © 2009 Wiley‐Liss, Inc.
Optimized high‐resolution mapping of magnetization transfer (MT) at 3 Tesla for direct visualization of substructures of the human thalamus in clinically feasible measurement time
Authors: Gringel Tabea , Schulz‐Schaeffer Walter , Elolf Erck , Frölich Andreas , Dechent Peter , Helms Gunther
Published: May 2009

Purpose

To optimize contrast‐to‐noise and spatial resolution of a FLASH‐based magnetization transfer (MT) protocol for visualization of substructures in human thalamus.

Materials and Methods

Healthy adults were examined at 3 Tesla with a three‐dimensional (3D) spoiled gradient‐echo sequence. The signal‐to‐noise ratio (SNR) was increased by averaging eight bipolar echo acquisitions (mean echo time = 12.3 ms; bandwidth = 370 Hz/pixel). Three isotropic datasets with different weighting (proton density: flip angle/repetition time = 7°/30 ms; T1: 20°/30 ms and MT: 10°/48 ms, Gaussian MT prepulse) yielded maps of T1, signal amplitude, MT ratio and MT saturation for comparison to MP‐RAGE images. Measuring time was 23 min using partial k‐space acquisition. First, the SNR of MT saturation maps in thalamus was optimized by means of the excitation flip angle. Then, noise and partial volume effects were traded off by means of the resolution. Finally, the contrast within the thalamus and to adjacent structures was compared between different maps.

Results

The optimized MT saturation maps at 0.95 mm isotropic resolution provided the highest contrast. It was most prominent between structures of high axonal content (internal medullary lamina, ventral nuclei) and those containing predominantly neuronal somata (pulvinar, mediodorsal thalamus, geniculate bodies).

Conclusion

Semiquantitative MT saturation maps provide an enhanced intra‐thalamic contrast. The borders and nuclear groups of the thalamus are reliably delineated; individual assignment of singular nuclei seems feasible. J. Magn. Reson. Imaging 2009;29:1285–1292. © 2009 Wiley‐Liss, Inc.
Rosette spectroscopic imaging: Optimal parameters for alias‐free, high sensitivity spectroscopic imaging
Authors: Schirda Claudiu V. , Tanase Costin , Boada Fernando E.
Published: May 2009

Purpose

To optimize the Rosette trajectories for fast, high sensitivity spectroscopic imaging experiments and to compare this acquisition technique with other chemical shift imaging (CSI) methods.

Materials and Methods

A framework for comparing the sensitivity of the Rosette Spectroscopic Imaging (RSI) acquisition to other spectroscopic imaging experiments is outlined. Accounting for hardware constraints, trajectory parameters that provide for optimal sampling and minimal artifact production are found. Along with an analytical expression for the number of excitations to be used in an RSI experiment that is provided, the theoretical precompensation weights used for optimal image reconstruction are derived.

Results

The spectral response function for RSI is shown to be approximately the same as the point spread function of standard Fourier reconstructions. While the signal‐to‐noise ratio (SNR) for an RSI experiment is reduced by the inherent nonuniform sampling of these trajectories, their circular k‐space support and speed of spatial encoding leads to greater SNR efficiency and improvements in the total data acquisition time relative to the gold standard CSI approach with square k‐space support and to similar efficiency to spiral CSI acquisitions. Numerical simulations and in vivo experimental data are presented to demonstrate the properties of this data acquisition technique.

Conclusion

This work demonstrates the use of Rosette trajectories and how to achieve improved efficiency for these trajectories in a two‐dimensional spectroscopic imaging experiment. J. Magn. Reson. Imaging 2009;29:1375–1385. © 2009 Wiley‐Liss, Inc.