bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating the Influence of Nitrogen Transformations on Nitrate Leaching in Soils
Authors: Ren Li , Ma Junhua , Zhang Renduo
Published: August 2007

It is challenging to estimate N leaching in soils attributable to complicated physical, chemical, and biological processes. In this study, a transfer function model was developed to simulate the outflow concentration of NO3 in the field, considering the influence of transient water flow, input of applied N, initial residual N in the soil, and main N transformations on the NO3–N leaching process. The N transformations in the model included immobilization, mineralization, volatilization, and plant uptake. In the probability density function of NO3–N, a weighting factor was introduced to quantify the leaching contributions from applied and residual N. A field experiment was conducted for 196 d during the growing seasons of winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.). Soil water potential and NO3 concentrations were measured during the study period along two soil profiles to a depth of 2 m: at 0.10‐m intervals from the soil surface to the 1‐m depth, and at 0.20‐m intervals from 1 to 2 m. A comparison between the experimental data and simulated results with the transfer function showed that the model provided reasonable predictions of the N leaching process as well as the total amount leached at the 2‐m depth. Results also indicated that by considering the transient water condition and N transformations, the transfer function significantly increased the estimation accuracy. Compared with the measured data, relative errors of the estimated total N leached were 1 and 20% with and without considering the transient water condition and the N transformations, respectively. The transfer function with the weighting factor can be useful to estimate the contributions from the applied and residual N to the leaching process in the field.
Mechanism of Dinitrophenol Herbicide Sorption by Smectites in Aqueous Suspensions at Varying pH
Authors: Pereira Tanya R. , Laird David A. , Johnston Cliff T. , Teppen Brian J. , Li Hui , Boyd Stephen A.
Published: August 2007

The compound 4,6‐dinitro‐o‐cresol (DNOC) is an important pesticide that is strongly adsorbed by smectite clays. Because DNOC is a weak acid with an acid dissociation constant (pKa) of about 4.4, pH was hypothesized to be a dominant state variable controlling sorption. In this study, we quantified the effect of pH, saturating cation (K+ and Ca2+), and freeze‐drying on adsorption of DNOC by two reference smectites with different charge densities (SWy‐2 and SAz‐1) in dilute aqueous suspensions. The smectite–DNOC systems were adjusted from pH 3 to 7. Nearly 100% of added DNOC was adsorbed by K+–saturated SWy‐2 at pH 3, and sorption decreased with increasing pH to 62% at pH 7. Sorption of DNOC on K+–saturated SAz‐1 decreased from 94% at pH 3 to 31% at pH 7. Suspended Ca2+–saturated SWy‐2 adsorbed 82% of added DNOC at pH 3 but sorption decreased to 18% for pH 4 and above. Across the entire pH range, Ca2+–saturated SAz‐1 sorbed about 12% of added DNOC. Slightly larger amounts of DNOC were adsorbed by the “never dried” (not freeze‐dried) smectites compared with the freeze‐dried and rehydrated smectites. Analysis of supernatants from the K+–saturated SAz‐1–DNOC systems indicated co‐adsorption of K+ with DNOC in the phenolate form at pH values above the pKa of DNOC. At lower pH values, DNOC adsorption and complexation with interlayer K+ resulted in less K+ exchange by H+ compared with the control without DNOC. These mechanisms explain the minimal influence of pH on the adsorption of DNOC by the K+–saturated smectites.
Sediment Retention by a Stiff Grass Hedge under Subcritical Flow Conditions
Authors: Hussein J. , Ghadiri H. , Yu B. , Rose C.
Published: August 2007

Reduction of diffuse fluxes of sediments from catchments is frequently achieved through the use of vegetative buffers, but the dynamics of this reduction are not fully understood. The physical processes involved in sediment deposition by a stiff grass buffer (hedge) at a low, subcritical flow rate were therefore examined. Flow experiments were performed in the Griffith University tilting‐flume simulated rainfall facility using a 0.3‐m‐width, vetiver (Vetiveria zizaniodes L., sterile cultivar Monto) hedge at a 5% slope. Sediments comprising a sandy soil (Podzol) and red clay (Ferralsol) were introduced into the flow upstream of the buffer and the resultant hydrology, sediment deposition, and outflow characteristics were measured. Flow retardation produced a backwater upstream of the vetiver hedge and sediment deposition varied with soil type in this backwater. The backwater region was greatly extended by the deposition process, increasing overall sediment trapping efficiency. Buffering action reduced mean sediment loads in the outflow to 3.2 and 6.0% of the inflow concentration for the Podzol and Ferralsol, respectively, with a significant difference (P < 0.01) between the soils. In contrast to other buffer research where deposited sediments were coarsest upstream of the backwater, we found the coarsest particles at the downstream end for the Podzol and Ferralsol, indicating possible bed load movement in addition to the deposition and entrainment processes that dominate supercritical flow. The type of flow therefore affects the size distribution as well as the amount and efficiency of sediment deposition in front of vetiver hedges.
Noncontact Shrinkage Curve Determination for Soil Clods and Aggregates by Three‐Dimensional Optical Scanning
Authors: Sander Till , Gerke Horst H.
Published: August 2007

The classical saran resin method for determination of the soil shrinkage characteristic (SSC) curves based on volume determination of saran‐coated clods is limited by water penetration during submersion, requires correction for the volume of coatings, and does not account for swelling. This study compared a novel noncontact method for SSC curve determination with the classical saran method. Natural, irregularly shaped clods of 18 to 45 g detached from four horizons of a clayey to loamy Chinese paddy soil were capillary saturated to a matric potential of −4 cm. During air drying, the changing clod volume was repeatedly measured by three‐dimensional optical scanning and the water content determined gravimetrically. After resaturation of the same clods, measurements were repeated with the saran method. Optical scanning of clods from various positions resulted in sets of point clouds that required comprehensive data processing. The final three‐dimensional volume objects were generated by adaptive triangulation. When assuming 0.3 to 0.8 g of water penetration for the saran method and a correction to account for a 20 and 18% loss of mass of air‐ and oven‐dry saran coatings, respectively, the SSC curves of the two methods were relatively similar. Spearman's rank correlation coefficient was 0.88 at the 95% confidence level. Errors for the new three‐dimensional method may occur during manual data processing. The new, three‐dimensional optical method is suitable to determine the SSC curve of relatively small, irregularly shaped clods with low to medium shrinkage in a wide range of water contents.
Contribution of Root vs. Leaf Litter to Dissolved Organic Carbon Leaching through Soil
Authors: Uselman Shauna M. , Qualls Robert G. , Lilienfein Juliane
Published: August 2007

Very little is known about dissolved organic matter (DOM) originating from fine roots in forest soils in comparison to DOM originating from leaf litter. To compare the fate of root‐ vs. leaf‐derived dissolved organic carbon (DOC), we added 14C‐labeled root litter at depths of 10 cm, a “shallow root treatment,” and 40 cm, a “deep root treatment,” and leaf litter to 50‐cm column soil microcosms. We analyzed the solution leached from the columns during a 47‐d simulated snowmelt treatment, trapped respired 14CO2, and measured translocation of 14C within the columns. In general, total C losses, as a percentage of 14C added, were substantial and highest for the leaf treatment (8.2% leached as DOC, 13.4% translocated, and 14.8% respired), intermediate for the shallow root treatment (2.3, 5.2, and 3.9%, respectively) and lowest for the deep root treatment (2.4, 1.9, and 2.9%, respectively). The C lost to DOC leaching was similar, however, for the deep and shallow root treatments. As a percentage of total losses (i.e., the sum of DOC leaching, respiration, and translocation), 14C lost as DOC leaching was significantly higher in the deep root treatment than other treatments. These observations suggest that leaf‐derived DOC may contribute to the formation of an A horizon and even to accumulation of soil organic carbon (SOC) in the B horizon during soil development, either by adsorption or microbial biomass incorporation. The 14C data further showed that root‐derived DOC, especially from root litter at greater depths, may help explain both the presence of SOC at depth and a portion of the DOC draining from soil profiles.
Automation and Use of Mini Disk Infiltrometers
Authors: Madsen Matthew D. , Chandler David G.
Published: August 2007

Measurement replication and objectivity of field soil hydraulic properties can be increased through automation. The goals of this study were to test two automated mini disk infiltrometers (AMDI). Both devices were fitted with differential pressure transducers connected to compact data loggers. Instrument design, method of calculation, and soil moisture condition all affected measured unsaturated hydraulic conductivity [K(h)] and sorptivity (S) at pressure head h = −2.0 cm. We found that the type of AMDI with a capillary tube head control can be operated at inclination angles up to 25° and returned the least variance in K(h) and S if data were not partitioned for calculation. Changing the initial soil moisture content from 0.07 to 0.26 m3 m−3, however, was found to influence K(h) calculation by up to 50% for a silt loam soil. The K(h) measured by the type of AMDI with a bubble chamber head control and larger disk diameter was less dependent on soil moisture content, but more sensitive to inclination.
Sample Pretreatment and Phosphorus Speciation in Wetland Soils
Authors: Turner Benjamin L. , Newman Susan , Cheesman Alexander W. , Reddy K. Ramesh
Published: August 2007

We assessed the influence of sample pretreatment on the amounts and forms of P extracted in NaOH–EDTA (ethylenediamine tetraacetic acid) from a series of contrasting wetland soils from the Florida Everglades. Samples of unconsolidated benthic floc and underlying soil (0–10 cm) were extracted either fresh (overnight refrigeration only), air dried (10 d at ∼30°C), or frozen at −80°C and lyophilized (∼48 h), before extraction and solution 31P nuclear magnetic resonance (NMR) spectroscopy. Significant differences in total P extraction following pretreatment were detected for one out of four benthic floc samples and three out of four soil samples, although the changes were inconsistent: in two cases the total P extraction increased, while in two others it decreased. Assessment of the P composition by solution 31P NMR spectroscopy revealed differences among treatments, although these were mostly within the range of error associated with replicate analyses; however, DNA was not detected in a fresh sample of calcareous benthic floc, despite representing an important component of the organic P extracted from dried samples. The apparent sample‐specific nature of the changes confirms the importance of carefully assessing pretreatment effects in studies of soil organic P in wetlands.
Infiltration Rate vs. Gas Composition and Pressure in Soil Columns
Authors: Prunty Lyle , Bell Joel
Published: August 2007

Infiltration is influenced by soil gases. Studies have found that CO2 has a large impact on infiltration. Since CO2 is highly soluble, soil flooded with it before infiltration has greater saturation and a greater infiltration rate. Our objective was to compare infiltration rates when soil pore gas consisted of (i) CO2 at atmospheric pressure, (ii) air at atmospheric pressure, and (iii) air at various vacuum levels. A vacuum should, similar to CO2, reduce encapsulated gas and increase the infiltration rate. Results were that infiltration under 1‐ to 2‐mm constant‐head conditions tended to be more rapid at low air pressures. Falling‐head infiltration, from 67.8‐ to 13.8‐cm water head, was fastest with CO2, intermediate with a vacuum that removed all dry air gases, and slowest with air at atmospheric pressure. The final falling‐head infiltration rates with CO2 and vacuum were 1.9 and 1.6 times faster, respectively, than with atmospheric air.
Advanced fractionation technology for the oleochemical industry
Authors: Faessler Peter , Kolmetz Karl , Seang Kek Wan , Lee Siang Hua
Published: August 2007

Steadily increasing requirements on fractionation demands in the oleochemical industry require advanced separation technology. Today, often a distillation column has not only to process several different feeds, but also be able to produce two different products simultaneously. Divided wall columns have been proposed and used in the chemical industry, but there are, presently, few applications of divided wall columns in the oleochemical sector. The main reason prohibiting their use might be in the limited familiarity, higher requirements on operation, potential corrosion problems and last but not least, limited flexibility.

Fractionation columns with added side stripper are a well‐proven way to satisfy increased demand of separation duties. The availability of second‐generation structured packing increases the efficiency and reduces pressure drops while making it possible to increase capacity and/or product purities. A lower pressure drop has a positive impact on the separation itself. Combining these effects with an increase in capacity will result in a synergy effect on the separation performance.

The newly developed BXPlus structured packing is a powerful tool for advanced Glycerin separation, combining good wettability resulting in high efficiency with low‐pressure drop. New columns can be designed much more compactly. Revamps will improve both capacity and/or purity. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
The energy challenge of direct contact membrane distillation in low temperature concentration
Authors: Bui V. A. , Nguyen M. H. , Muller J.
Published: August 2007

Direct contact membrane distillation (DCMD) was operated at low temperatures from 25 to 40 °C to suit the purpose of thermally concentrating sensitive liquid foods, especially fruit juices to high solid content concentrate with most of the quality attributes preserved.

A lab scale DCMD unit has been set up at the Centre for Plant and Food Science, University of Western Sydney. Hollow fibre modules (HFM) using five types of fibres of polyvinylidene fluoride (PVDF) and Halar material, with mass transfer areas ranging from 281 to 573 cm2 were employed. Experiments for concentration of glucose solutions from 30 to 60% (w/w) were carried out. Results indicated that not only the operating conditions were important, but also the membrane properties. It was found that Halar fibres were performing 2–3 times better than PVDF fibres in term of removing water from the feed, and 3–4 times better in term of energy saving. Results also showed that an increase of the feed inlet temperature from 25 to 40 °C improved the mass flux up to 6 times and energy efficiency (EE) up to 2.5 times depending on the feed concentration.

With flux up to 2.88 kg m−2 h−1 for PVDF and 5.83 kg m−2 h−1 for Halar fibres when concentrating 30% glucose solution at 40 °C, DCMD appeared to be an attractive concentration technique, when product quality is the priority. However, with EE from as low as 2.1–14.9%, PVDF fibres employed in the study seemed not to be very suitable for DCMD liquid food concentration under low temperature condition. DCMD in Halar fibres with EE up to 45.6% still encounters the challenge of energy and could only be cost competitive to osmotic distillation and evaporative concentration when cheaper energy sources or heat recovery measures are employed. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
gem‐Dihalocyclopropanes as Building Blocks in Natural‐Product Synthesis: Enantioselective Total Syntheses of ent‐Erythramine and 3‐epi‐Erythramine
Authors: Stanislawski Pauline C. , Willis Anthony C. , Banwell Martin G.
Published: August 2007

ent‐Erythramine ((−)‐1), the enantiomer of the alkaloid erythramine, was prepared in 15 steps from known compounds. The first of three pivotal bond‐forming steps in the synthesis was a Suzuki–Miyaura cross‐coupling reaction of the starting materials to give a bis‐silyl ether. The second involved silver(I)‐induced electrocyclic ring opening of the gem‐dichlorocyclopropane formed in the next step and trapping of the ensuing π‐allyl cation by the tethered nitrogen atom to give, following cleavage of the allyloxycarbonyl protecting group, an approximately 5:6 mixture of the chromatographically separable diastereoisomeric spirocyclic products. In the third critical bond‐forming reaction, the iodide formed from one of the diastereoisomers underwent a radical‐addition/elimination reaction sequence that led to (−)‐1 in 89 % yield. The application of the same sequence of transformations to the other diastereoisomer afforded 3‐epi‐(+)‐erythramine (3‐epi‐(+)‐1).
Dosimetric evaluation and comparison of different RF exposure apparatuses used in human volunteer studies
Authors: Boutry Clémentine M. , Kuehn Sven , Achermann Peter , Romann Albert , Keshvari Jafar , Kuster Niels
Published: August 2007

The aim of this study was to provide the information necessary to enable the comparison of exposure conditions in different human volunteer studies published by the research groups at the Universities of Turku, Swinburne, and Zurich. The latter applied a setup optimized for human volunteer studies in the context of risk assessment while the first two applied a modified commercial mobile phone for which detailed dosimetric data were lacking. While the Zurich Setup exposed the entire cortex of the target hemisphere, the other two setups resulted in only very localized exposure of the upper cheek, and concentrated on a limited area of the middle temporal gyrus just above the ear. The resulting peak spatial SAR averaged over 1 g of the cortex was 0.19 W/kg of the Swinburne Setup, and 0.31 W/kg for the Turku Setup, compared to 1 W/kg for the Zurich Setup. The average exposure of the thalamus was 5% and 9% of the Zurich Setup results for the Swinburne and Turku Setups, respectively. In general, the phone‐based setup results in only reasonably defined exposures in a very limited area around the maximum exposure; the exposure of the rest of the cortex was low, and may vary greatly as a function of the setup, position, and local anatomy. The analysis confirms the need for a carefully designed exposure setup that exposes the relevant brain areas to a well‐defined level in human volunteer studies, and shows that studies can only be properly compared and replicated if sufficiently detailed dosimetric information is available. Bioelectromagnetics 29:11–19, 2008. © 2007 Wiley‐Liss, Inc.
Lack of promotion effects of 50 Hz magnetic fields on 7,12‐dimethylbenz(a)anthracene‐induced malignant lymphoma/lymphatic leukemia in mice
Authors: Negishi Tadashi , Imai Setsuo , Shibuya Kazumoto , Nishimura Izumi , Shigemitsu Tsukasa
Published: August 2007

New‐born CD‐1 mice were initiated with a single subcutaneous injection of 60 µg 7,12‐dimethylbenz(a)anthracene (DMBA) within 24 h after birth. After weaning, the mice were randomly divided into five groups of 100, 50 males and 50 females each. One group served as a cage control. The other four groups of mice were exposed to either 0 (sham‐exposed), 7, 70, or 350 µT(rms) circularly polarized 50 Hz magnetic fields (MFs) for 22 h/day, 7 days/week for 30 weeks. Animals were observed daily and the development of malignant lymphoma/lymphatic leukemia was examined histopathologically. The experiment was conducted twice. There was no observed sexual difference in the cumulative proportions of mice with malignant lymphoma/lymphatic leukemia and a 3‐way analysis of deviance using the Cox regression model revealed no interactions between experiment, sex, or group. The cumulative proportions of mice with malignant lymphoma/lymphatic leukemia in the MF‐exposed groups were not significantly higher than those in the sham‐exposed group of each sex in individual experiments and in males and females combined in each experiment, and in all the animals from the two experiments combined. These data provide no evidence to support the hypothesis that power frequency MFs is a significant risk factor for hematopoietic neoplasia. Bioelectromagnetics 29:29–38, 2008. © 2007 Wiley‐Liss, Inc.
Mobile phone base station radiation does not affect neoplastic transformation in BALB/3T3 cells
Authors: Hirose H. , Suhara T. , Kaji N. , Sakuma N. , Sekijima M. , Nojima T. , Miyakoshi J.
Published: August 2007

A large‐scale in vitro study focusing on low‐level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT‐2000) cellular system was conducted to test the hypothesis that modulated RF fields affect malignant transformation or other cellular stress responses. Our group previously reported that DNA strand breaks were not induced in human cells exposed to 2.1425 GHz Wideband Code Division Multiple Access (W‐CDMA) radiation up to 800 mW/kg from mobile radio base stations employing the IMT‐2000 cellular system. In the current study, BALB/3T3 cells were continuously exposed to 2.1425 GHz W‐CDMA RF fields at specific absorption rates (SARs) of 80 and 800 mW/kg for 6 weeks and malignant cell transformation was assessed. In addition, 3‐methylcholanthrene (MCA)‐treated cells were exposed to RF fields in a similar fashion, to assess for effects on tumor promotion. Finally, the effect of RF fields on tumor co‐promotion was assessed in BALB/3T3 cells initiated with MCA and co‐exposed to 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). At the end of the incubation period, transformation dishes were fixed, stained with Giemsa, and scored for morphologically transformed foci. No significant differences in transformation frequency were observed between the test groups exposed to RF signals and the sham‐exposed negative controls in the non‐, MCA‐, or MCA plus TPA‐treated cells. Our studies found no evidence to support the hypothesis that RF fields may affect malignant transformation. Our results suggest that exposure to low‐level RF radiation of up to 800 mW/kg does not induce cell transformation, which causes tumor formation. Bioelectromagnetics 29:55–64, 2008. © 2007 Wiley‐Liss, Inc.
The Reactivity of Calicheamicin γ1I in the Minor Groove of DNA: The Decisive Role of the Environment
Authors: Kraka Elfi , Tuttle Tell , Cremer Dieter
Published: August 2007

Triggering and Bergman cyclization of calicheamicin γ1I outside and inside the minor groove of the duplex 9mer‐B‐DNA sequence d(CACTCCTGG)⋅d(CCAGGAGTG) were investigated by using density functional theory and molecular mechanics (DFT and MM) descriptions in which the ligand is completely described at the DFT and the receptor at the MM level. The calculated docking energy of calicheamicin γ1I (−12.5 kcal mol−1) is close to the measured value of −9.7 kcal mol−1 and the site specificity is in line with experimental observations. Calicheamicin is triggered in the minor groove in such a way that out of a cyclohexenone by Michael addition an E rather than a Z form of a cyclohexanone is formed, which in turn adopts a chair rather than a twistboat form. Decisive for the stereochemistry of the Michael addition is the orientation of the carbamate substituent at the headgroup of calicheamicin. Triggered calicheamicin can undergo the Bergman cyclization at body temperature only if present in its E chair form (activation enthalpy 16.4 kcal mol−1). An intermediate biradical is formed (docking energy −13.6 kcal mol−1), which has a sufficient lifetime to abstract two hydrogen atoms. Hydrogen abstraction is a two‐ rather than one‐step process and involves the C5(H5′) atom first and then the T22(H4′) atom in line with experimental observations. The decisive role of using a DFT rather than an MM description for the ligand is documented.
Organocatalysed Asymmetric β‐Amination and Multicomponent syn‐Selective Diamination of α,β‐Unsaturated Aldehydes
Authors: Jiang Hao , Nielsen Johanne B. , Nielsen Martin , Jørgensen Karl Anker
Published: August 2007

An easy and affordable route for obtaining chiral β‐aminated‐ and α,β‐diaminated aldehydes, 1,3‐aminoalcohols, and related compounds by using organocatalysis is presented. The chiral secondary amine (S)‐2‐[bis(3,5‐bistrifluoromethylphenyl)trimethylsilanyloxymethyl]pyrrolidine is used as the catalyst to activate α,β‐unsaturated aldehydes, which allows succinimide to add in a 1,4‐regio‐ and stereoselective fashion thereby forming N‐protected 1,3‐aminoaldehydes in good yields and enantioselectivities. This is followed by two easy transformations giving rise to optically active 1,3‐aminoalcohols, a common motif in many biologically active compounds, for example, fibrinogen receptor antagonists. Furthermore, optically active α,β‐syn‐diaminated aldehydes were obtained by the addition of diethyl azodicarboxylate in a one‐pot reaction.
New Silver Tellurates — The Crystal Structures of a Third Modification of Ag2Te2O6 and of Ag4TeO5.
Authors: Weil Matthias
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Structural Characterization of Two New Hexagonal Osmates: Ba2Fe0.92Os1.08O6 and Ba2Co0.77Os1.23O6.
Authors: Gemmill William R. , Smith Mark D. , zur Loye Hans‐Conrad
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantioselective Addition of Alkenylzinc Reagents to Aldehydes with Organoboronates as the Alkenyl Source.
Authors: Chai Zhuo , Liu Xin‐Yuan , Zhang Jun‐Kang , Zhao Gang
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Stereocontrolled Access to α‐Fluoro‐β‐ketoesters.
Authors: Delarue‐Cochin Sandrine , Bahlaouan Bouchaib , Hendra Frederic , Ourevitch Michele , Joseph Delphine , Morgant Georges , Cave Christian
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Chemical Properties of 5‐Alkylsulfonyl‐1‐(4‐nitrophenyl)tetrazoles (III).
Authors: Egorova N. G. , Artamonova T. V. , Koldobskii G. I.
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Discovery of 4‐Amino‐5,6‐biaryl‐furo[2,3‐d]pyrimidines as Inhibitors of Lck: Development of an Expedient and Divergent Synthetic Route and Preliminary SAR.
Authors: DiMauro Erin F. , et al. et al.
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Double Mannich‐Type Reaction in the 1,4,5,6‐Tetrahydropyridine‐2‐thiolate Series: A Convenient Approach to Functionalized 3,7‐Diazabicyclo[3.3.1]nonane Derivatives.
Authors: Dotsenko Victor V. , Krivokolysko Sergey G. , Litvinov Victor P.
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The First Total Synthesis of Telephiose A.
Authors: Sato Ken‐ichi , Sakai Koudai , Tsushima Keiko , Akai Shoji
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Inflammatory breast cancer (IBC) and patterns of recurrence
Authors: Cristofanilli Massimo , Valero Vicente , Buzdar Aman U. , Kau Shu‐Wan , Broglio Kristine R. , Gonzalez‐Angulo Ana Maria , Sneige Nour , Islam Rabiul , Ueno Naoto T. , Buchholz Thomas A. , Singletary Sonja E. , Hortobagyi Gabriel N.
Published: August 2007

BACKGROUND.

Inflammatory breast cancer (IBC) is the most aggressive manifestation of primary breast cancer. The authors compared the prognostic features of IBC and non‐IBC locally advanced breast cancer (LABC) to gain insight into the biology of this disease entity.

METHODS.

This retrospective analysis consisted of 1071 patients, comprising 240 patients with IBC and 831 patients with non‐IBC LABC who were enrolled in 10 consecutive clinical trials (5 from each disease group). All patients received similar multidisciplinary treatment. The authors measured time to disease recurrence for each individual site from the start of treatment to the date of disease recurrence or last follow‐up (recurrence‐free survival) and overall survival rates to the date of last follow‐up or death.

RESULTS.

The median follow‐up period was 69 months (range, 1–367 months). Pathologically complete response rates were 13.9% and 11.7% in the IBC and non‐IBC LABC groups, respectively (P = .42). The 5‐year estimates of cumulative incidence of recurrence were 64.8 % and 43.4% (P < .0001), respectively, for IBC and non‐IBC LABC. IBC had significantly higher cumulative incidence of locoregional recurrence and distant soft‐tissue and bone disease. The 5‐year overall survival (OS) rate was 40.5% for the IBC group (95% CI, 34.5%–47.4%) and 63.2% for the non‐IBC LABC group (95% CI, 60.0%–66.6%; P < .0001).

CONCLUSIONS.

IBC was associated with a worse prognosis and a distinctive pattern of early recurrence compared with LABC. These data suggested that investigating factors affecting “homing” of cancer cells may provide novel treatment strategies for IBC. Cancer 2007. © 2007 American Cancer Society.
Patient selection, cancer control, and complications after salvage local therapy for postradiation prostate‐specific antigen failure
Authors: Nguyen Paul L. , D'Amico Anthony V. , Lee Andrew K. , Warren Suh W.
Published: August 2007

Among men who experience prostate‐specific antigen (PSA) failure after external beam radiation or brachytherapy (RT), many will harbor occult micrometastases; however, a significant minority will have a true local‐only failure and, thus, potentially may benefit from a salvage local therapy. Those most likely to have a local‐only failure initially have low‐risk disease (PSA < 10 ng/mL, Gleason score ≤6, clinical T1c or T2a tumor status), pretreatment PSA velocity < 2.0 ng/mL per year at the time of initial presentation, interval to PSA failure > 3 years, PSA doubling time > 12 months, negative bone scan and pelvic imaging, and positive rebiopsy. In addition, men with presalvage PSA levels > 10 ng/mL, presalvage T3/T4 disease, or presalvage Gleason scores ≥7 on a rebiopsy sample without significant RT effects are unlikely to be cured by salvage local therapy. Based on a review of all series of post‐RT salvage prostatectomy, cryosurgery, and brachytherapy published in English since 1990, morbidity can be substantial. Although urinary incontinence appeared to be greater after salvage prostatectomy (41%) or cryosurgery (36%) than after brachytherapy (6%), patients who received salvage brachytherapy faced a 17% risk of grade 3 or 4 genitourinary complications and a fistula risk that averaged 3.4% across all series. From this review, the authors concluded that prospective randomized studies are needed to determine the relative efficacy of the 3 major local salvage modalities and that additional research is needed to identify factors associated with an increased risk of significant complications to improve patient selection and to augment the benefit/risk ratio associated with attempts to cure local‐only recurrences after radiation therapy. Cancer 2007. © 2007 American Cancer Society.
Oxidation of NIII and N–I by an {Mn4O6}4+ Core in Aqueous Media: Proton‐Coupled Electron Transfer
Authors: Das Suranjana , Mukhopadhyay Subrata
Published: August 2007

[Mn4(μ‐O)6(bipy)6]4+ (14+; bipy = 2,2′‐bipyridine) and its conjugate acid [Mn4(μ‐O)5(μ‐OH)(bipy)6]5+ (1H5+) quantitatively oxidise NIII (HNO2 and NO2–) and N–I (NH3OH+ and NH2OH) to NV (nitrate) and NI (nitrous oxide), respectively, in aqueous solution (pH 2.0–6.0), with 1H5+ reacting much faster than 14+. An uncommon feature of these reactions is the kinetic superiority of HNO2 over its conjugate base NO2–. NH2OH, however, behaves normally ― the conjugate acid NH3OH+ is less reactive than NH2OH. These reactions show remarkable kinetic isotope effects: the observed rate of NIII oxidation increases in D2O media whereas the N–I oxidation rate slows down in media enriched with D2O. A search of the available data on the redox kinetics of multinuclear oxidants suggests that the title {Mn4O6}4+ reduction by NIII, the rate of which is accelerated in D2O, is the only one established so far. A hydrogen atom transfer (HAT) mechanism (1e, 1H+; electroprotic) is proposed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Reactions of 1,2,4‐Trithiolanes with Nonacarbonyldiiron: Sulfurdithiolatodiiron and ‐tetrairon Complexes as Mimics for the Active Site of [Fe‐only] Hydrogenase
Authors: Windhager Jochen , Görls Helmar , Petzold Holm , Mloston Grzegorz , Linti Gerald , Weigand Wolfgang
Published: August 2007

The reactions of 1,2,4‐trithiolane (1a), 3,3,5,5‐tetramethyl‐1,2,4‐trithiolane (1b), 3,3,5,5‐tetraethyl‐1,2,4‐trithiolane (1c), 3,3,5,5‐bis(pentamethylene)‐1,2,4‐trithiolane (1d) and di‐spiro{tricyclo[3.3.1.1]decane‐2,3″‐(1,2,4)‐trithiolane‐5′,2′‐tricyclo[3.3.1.1]decane} (1e) with nonacarbonyldiiron (2) have been investigated. The sulfurdithiolatodiiron complexes 3a–e, which can be considered as novel model complexes of the active site of the [Fe‐only] hydrogenase, were isolated as the main products of these reactions. X‐ray structure analyses were performed on compounds 3b–e. The carbon dithiolato (SCR2S)‐bridged diiron side‐products 4a–e and the tetranuclear clusters 6b–d were also obtained and characterised by X‐ray diffraction analysis (4b–e and 6b–d). In contrast, the reaction of 1e with 2 affords the trinuclear complex 7, which contains a side‐on bonded adamantanethione, besides 3e and 4e. Finally, the reaction of 3a with two equivalents of (Et4N)CN gives the monocyanide complex 8 in good yield. Density functional calculations have been performed to evaluate the bonding situation in the di‐ and tetranuclear clusters. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Antecedents, consequences, and moderators of time perspective heterogeneity for knowledge management in MNO teams
Authors: Gibson Cristina B. , Waller Mary J. , Carpenter Mason A. , Conte Jeffrey M.
Published: August 2007

Multinational organizations (MNOs), more so than other organizations, are likely to require individuals with different perspectives, experiences, and backgrounds to form teams and collaboratively manage knowledge. We develop a framework that shows why variations in time perspectives among members of teams occur and how such differences can exert significant but unacknowledged influences on knowledge management efforts in MNOs, including: (1) innovativeness of knowledge created (2) speed of knowledge creation and (3) speed of knowledge transfer between teams. We also provide new insights into benefits of time perspective heterogeneity for teams managing knowledge. Copyright © 2007 John Wiley & Sons, Ltd.
Faking emotional intelligence (EI): comparing response distortion on ability and trait‐based EI measures
Authors: Day Arla L. , Carroll Sarah A.
Published: August 2007

We compared the susceptibility of two emotional intelligence (EI) tests to faking. In a laboratory study using a within‐subjects design, participants completed the EQ‐i and the MSCEIT in two sessions. In the first session (i.e., the ‘applicant condition’), participants were given a job description and asked to respond to the EI measures as though they were applying for that job. Participants returned 2 weeks later to repeat the tests in a ‘non‐applicant’ condition in which they were told to answer as honestly as possible. Mean differences between conditions indicated that the EQ‐i was more susceptible to faking than the MSCEIT. Faking indices predicted applicant condition EQ‐i scores, after controlling for participants' non‐applicant EQ‐i scores, whereas the faking indices were unrelated to applicant condition MSCEIT scores, when the non‐applicant MSCEIT scores were controlled. Using top‐down selection, participants were more likely to be selected based on their applicant condition EQ‐i scores than their non‐applicant EQ‐i scores, but they had an equal likelihood of being selected based on their MSCEIT scores from each condition. Implications for the use of these two EI tests are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
The relationship between rock glacier and contributing area parameters in the Front Range of Colorado
Authors: Janke Jason , Frauenfelder Regula
Published: August 2007

Rock glaciers are an end unit of the coarse debris system that links frost weathering and rockfall to debris transport in mountainous environments. By examining topographic and climatic controls on creep, a better understanding of rock glacier formation and evolution could be obtained. A series of statistical tests were run comparing contributing area parameters (width, length, area, slope, headwall height, etc.) and rock glacier variables (width, length, area, thickness, slope, creep and temperature) in the Front Range of Colorado. Results showed that rock glacier width had the strongest correlation with contributing area width due to an abundance of lobate rock glaciers (r = 0.78). Rock glacier area and contributing area size were also related (r = 0.74), but are also a function of talus production factors. Mean surface velocity appears to be better correlated with thickness (r = 0.58) and length (r = 0.62), rather than slope (r = 0.33). Mean annual air temperature had a stronger exponential relationship with maximum velocities (r = 0.76) compared to mean annual velocity (r = 0.60). Front Range rock glacier velocities tend to decrease with warming, suggesting that the volume of ice and debris, rates of shear in plastic layers, or melt water may have a greater influence on deformation. Copyright © 2007 John Wiley & Sons, Ltd.
Development of a two‐step screening ESI‐TOF‐MS method for rapid determination of significant stress‐induced metabolome modifications in plant leaf extracts: The wound response in Arabidopsis thaliana as a case study
Authors: Grata Elia , Boccard Julien , Glauser Gaetan , Carrupt Pierre‐Alain , Farmer Edward E. , Wolfender Jean‐Luc , Rudaz Serge
Published: August 2007

To study the stress‐induced effects caused by wounding under a new perspective, a metabolomic strategy based on HPLC‐MS has been devised for the model plant Arabidopsis thaliana. To detect induced metabolites and precisely localise these compounds among the numerous constitutive metabolites, HPLC‐MS analyses were performed in a two‐step strategy. In a first step, rapid direct TOF‐MS measurements of the crude leaf extract were performed with a ballistic gradient on a short LC‐column. The HPLC‐MS data were investigated by multivariate analysis as total mass spectra (TMS). Principal components analysis (PCA) and hierarchical cluster analysis (HCA) on principal coordinates were combined for data treatment. PCA and HCA demonstrated a clear clustering of plant specimens selecting the highest discriminating ions given by the complete data analysis, leading to the specific detection of discrete‐induced ions (m/z values). Furthermore, pool constitution with plants of homogeneous behaviour was achieved for confirmatory analysis. In this second step, long high‐resolution LC profilings on an UPLC‐TOF‐MS system were used on pooled samples. This allowed to precisely localise the putative biological marker induced by wounding and by specific extraction of accurate m/z values detected in the screening procedure with the TMS spectra.
Integration of arbuscular mycorrhiza inoculation in hydroseeding technology: effects on plant growth and inter‐species competition
Authors: Estaún V. , Vicente S. , Calvet C. , Camprubí A. , Busquets M.
Published: August 2007

Hydroseeding is a technique increasingly used to establish vegetation on large degraded areas, such as large‐scale road construction sites and quarries. Native grasses and legume species are used on rehabilitation and restoration projects as a first step in the recovery of such places, prior to the establishment of native forbs and shrubs that occurs at a slower pace. The effect of mycorrhizal inoculation on the development of nine species of grasses and legumes that can be potentially used in restoration processes in the Mediterranean area was studied, in microcosm experiments under greenhouse conditions. The effect of adding arbuscular mycorrhizal (AM) inoculum to a hydroseeding mixture was also investigated in greenhouse and in field conditions. In the hydroseeding experiments the mycorrhizal inoculum was added to the seed slurry in a jet agitated hydroseeding machine and sprayed to the soil surface with a pressurised spray in a one‐step application. The study shows that Glomus intraradices Schenk & Smith BEG72 is able to establish the symbiosis when applied at sowing while Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe BEG116 is not. It also confirms that legumes are more highly mycotrophic than grasses. The results of the hydroseeding experiments demonstrate the establishment of the symbiosis using this technology, both in the greenhouse and in the field. Mycorrhizal inoculation improved above ground plant growth and increased the legumes/grasses ratio. Copyright © 2007 John Wiley & Sons, Ltd.
Substrate‐Independent Stable and Adherent Reactive Surface Coatings and their Conversion with Amines
Authors: Kessler Daniel , Metz Nadine , Theato Patrick
Published: August 2007

Summary: To create stable, adherent and reactive surface coatings, a hybrid polymer composed of poly(methylsilsesquioxane) (PMSSQ) and poly(pentafluorophenyl acrylate) PFPA with a Mn of 32000 g/mol was prepared by a RAFT polymerization procedure. These hybrid polymer has been used for coating experiments. The PFPA part enabled a variable functionalization of the coating afterwards. The stability on various substrates (e.g. glass, PMMA, steel) was tested in an ISO tape test. These reactive surface coatings were modified using different amines, such as amino‐terminated PEG, dodecyl amine and N‐isopropyl amine. The conversion was analyzed by FT‐IR and contact angle measurements.
Photoinitiator‐Free Photopolymerization of Silicon‐Containing Maleimides Based on Electron‐Donor‐Acceptor Systems
Authors: Ahn Kwang‐Duk , Kang Jong‐Hee , Yoo Kynug Wook , Choo Dong Joon
Published: August 2007

Summary: Photocured coatings promise enhanced performance, higher productivity and an improved environmental impact on the favorable reduction or near elimination of volatile organic compounds. Increasing interest in the photocuring industry has been imposed on the “photoinitiator‐free photopolymerization [PIFP]” system based on the electron‐donor‐acceptor [EDA] concept, which commonly employs a mixture of a vinyl ether monomer (donor) and an N‐substituted maleimide or bismaleimide monomer (acceptor). The PIFP systems employing silicon‐containing maleimides together with vinyl ether monomers were firstly investigated and their photoreactions resulted in quite fast curing comparable to the conventional acrylate‐ based photocurable systems.
Colloidal Systems on the Basis of Novel Reactive Surfmers
Authors: Hevus Orest , Kohut Ananiy , Fleychuk Roman , Mitina Natalija , Zaichenko Oleksandr
Published: August 2007

Summary: New anion surfmers of the family of maleic acid asymmetrical esters have been synthesized. Some of its features in the process of emulsion copolymerization with styrene have been studied. The characteristics of covering, obtained on the basis of such latexes of new generation have been investigated as well.
Emulsion Polymerization of Styrene and Vinyl Acetate with Cationic Surfactant
Authors: Erkal Durdane , Senkal B. Filiz , Sarac Ayfer
Published: August 2007

Summary: In this study, the emulsion homopolymerization system containing vinyl acetate and styrene, potassium persulfate, and a new cationic surfactant was studied in the classical glass emulsion polymerization reactor. The effects of new polymeric emulsifier on the physicochemical properties of obtained vinyl acetate and styrene latex properties were investigated depending on surfactant percentage in homopolymerizations.
Effects of Confinement on the Kinetics of Formation of Sequential Semi‐Interpenetrating Polymer Networks
Authors: Alekseeva Tatiana , Lipatov Yuri , Sorochinskaya Lyubov , Dudarenko Galina
Published: August 2007

Summary: Peculiarities of formation kinetics of sequential semi‐interpenetrating polymer networks (semi‐IPNs) based on crosslinked polyurethane (PU) with different cross‐linking density and linear polystyrene (PS), polybutylmethacrylate (PBMA) and polymethacrylate acid (PMAA) have been studied. The experimental data show the dependence of the kinetic parameters of polymerization on Mc, this dependence being different for various monomers. Sharp discrepancy in molecular mass distribution of polymers formed in various matrices has been observed. The differences in dependencies of reaction kinetics and molecular mass distribution are supposed to be connected to various dependence of the chain growth and termination of various monomers on the density of network, i.e. on the confinements imposed by the intranetwork space.
Crystallization and Properties of Novel Polyurethanes Based on the Chain Extender Ethylene Glycol and Aromatic Diisocyanates of Variable Flexibility
Authors: Prisacariu Cristina , Scortanu Elena
Published: August 2007

Summary: Novel polyurethane elastomers (PUs) were synthesized with ethylene glycol (EG) as a chain extender. The macrodiol was poly(ethylene adipate) (PEA), MW = 2000 ± 50. Two isocyanates were employed: 4,4′‐methylene bis(phenyl isocyanate) (MDI) and 4,4′‐dibenzyl diisocyanate (DBDI). The conformational mobility of DBDI causes an unusually wide range of mechanical, physical and chemical properties, associated with the possibility of pronounced phase separation into a domain – matrix morphology, and with a higher tendency to crystallization and self‐association by hydrogen bonding. Materials were characterized by wide angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic mechanical analyses (DMA), and mechanical measurements. Results were discussed in terms of the effect of PUs crystallinity. In the case where the chain extender–diisocyanate couple was EG‐DBDI, the hard segments were observed to crystallize. The DBDI based PUs displayed higher flow stress in the hard phase caused by stronger phase segregation.