bluuebunny/crossref_metadata_2025 huggingface dataset:
Malaria-Induced Murine Pregnancy Failure: Distinct Roles for IFN-γ and TNF
Authors: Poovassery Jayakumar S. , Sarr Demba , Smith Geoffrey , Nagy Tamas , Moore Julie M.
Published: September 2009

Although an important role for excessive proinflammatory cytokines in compromise of pregnancy has been established, an immunological basis for malaria-induced fetal loss remains to be demonstrated. In this study, the roles of IFN-γ and TNF in Plasmodium chabaudi AS-induced fetal loss in mice were directly investigated. Pregnant IFN-γ−/− mice experienced a more severe course of infection compared with intact C57BL/6 mice, characterized by high parasitemia, severe anemia, and marked weight loss. However, fetal loss was delayed in these mice relative to intact controls. Because IFN-γ−/− mice exhibited sustained levels of plasma TNF, the role of this cytokine was examined. Whereas splenic tnf expression in C57BL/6 mice was highest 3 days before peak parasitemia, increased placental expression relative to uninfected mice was sustained, indicating that locally produced TNF may be important in malaria-induced pregnancy failure. Indeed, Ab neutralization of TNF resulted in preservation of embryos until day 12 of gestation, at which point all embryos were lost in untreated mice. Histological analysis revealed that TNF ablation preserved placental architecture whereas placentae from untreated infected mice had widespread hemorrhage and placental disruption, with fibrin thrombi in some maternal blood sinusoids. Consistent with a role for cytokine-driven thrombosis in fetal loss, expression of procoagulant tissue factor was significantly increased in the placentae of infected C57BL/6 mice but was reduced in mice treated with anti-TNF Ab. Together, these results suggest that IFN-γ contributes to malaria-induced fetal loss and TNF is a critical factor that acts by inducing placental coagulopathy.
Field Comparison of High-frequency Seismic Sources for Imaging Shallow (10–250m) Structures
Authors: van der Veen M. , Buness H. A. , Büker F. , Green A. G.
Published: September 2009

Several high-frequency seismic sources (i.e., sledgehammer, pipegun, weightdrop, and small- and intermediate-size vibrators) have been tested at a site characterized by a surface layer of very recent sediments overlying unconsolidated glacial and glaciolacustrine units. Reflections from very shallow [Formula: see text] to moderate [Formula: see text] depths were recorded. Evaluation of the different sources involved analyzing prominent features (e.g., reflections and signal-generated noise that includes complex patterns of interfering direct, guided, refracted, and surface waves) on source gathers, frequency spectra and stacked sections. Our experiments demonstrated that minor changes in local conditions (e.g., changes in ground-water table depth) may influence significantly the characteristics of the resulting data. Of the tested sources, the simple sledgehammer provided the highest resolution images at shallow depths [Formula: see text] and comparably good images at greater depths [Formula: see text]. Local changes in surficial sediments affected the quality of data generated by the small ([Formula: see text] reaction mass) vibrator; at many locations, the input energy was insufficient to illuminate the important geological structures. By comparison, the intermediate-size ([Formula: see text] reaction mass) vibrator provided high quality images to depths as great as [Formula: see text] (corresponding to the deepest reflection from near the base of unconsolidated sediments), but relatively strong airwaves and imprecise vibroseis correlation precluded the resolution of reflections from depths shallower than [Formula: see text]. Despite recent advances in vibratory systems, the humble, but cost-effective sledgehammer continues to be an attractive source for high-resolution seismic experiments.
Improvement in 1D TDEM Interpretation by Simultaneous Inversion of Data from Two Loop Configurations
Authors: Krivochieva Stefi , Chouteau Michel
Published: September 2009

This paper presents simultaneous inversion performed on data from central loop and offset receiver TDEM soundings. It is demonstrated that central loop and offset soundings complement each other and that the simultaneous 1D inversion of both data sets (1) yields rapid convergence and better resolution of the model parameters, (2) reduces the importance of distortion caused by induced polarization on interpretation, and (3) provides a good indication of the subsurface geometry in the measurement zone. Simultaneous inversion of central loop and different offset data sets are initially performed over a layered earth. The simultaneous inversion drastically improves interpretation obtained from the long offset data alone, but yields no noticeable improvement for the short offset sounding interpretation. Individual and simultaneous interpretation of central loop and offset soundings are then compared over a layered earth with a polarizable surface layer. The simultaneous interpretation reduces the importance of IP distortion affecting the central loop data and yields a more reliable model. Finally, central loop and offset data are calculated over a 3D conductive body embedded in layered host and individual and simultaneous inversions are performed. Lack of convergence and mediocre fit in simultaneous inversion indicate the presence of lateral conductivity variations. The simultaneous inversion is applied to two field examples from data collected in the Chalco Sub-Basin (Mexico). The first example consists in simultaneous inversion of two neighboring central loop soundings over an earth with no significant lateral conductivity changes. A slight enhancement in the resolution of model parameters is observed, but no substantial improvement in terms of misfit error or number of iterations is achieved compared to the single-site inversion. The second example shows simultaneous inversion of central loop and offset TDEM soundings when lateral conductivity changes occur. The combination of the two soundings never yields a final model that satisfies both data sets, showing the presence of a 2D or 3D heterogeneity in the vicinity of the two sounding sites.
Field Experimental Studies of a Riverbed Scour Measurement System
Authors: Davies E. B. , Mercado E. J. , O’Neill M. W. , McDonald J. A.
Published: September 2009

The effect of riverbed scour around bridge foundations has led to numerous bridge failures due to the undermining of piers or abutments by scour during floods. Monitoring of scour processes becomes very difficult during flood periods, at the time when scour is most prevalent. The objective of the study described in this paper was to test the concept that seismo-accoustic methods could be used as a basis for a scour monitor system that could operate during flood periods. These methods are based on using travel times of directly transmitted and refracted waves propagating through and in the vicinity of bridge foundations. A series of experiments designed to test these concepts was carried out at a field test site. The test site consisted of a water-filled pond that contained a small-scale replica of a bridge constructed with two cylindrical concrete piers. The pond also contained cased boreholes at various locations. The dimensions of the bridge structure were about one quarter the size of any bridge that might be of interest. Seismic waves were generated in and around the piers by use of a hammer or an air gun as the seismic source. Data were detected using hydrophones deployed in the cased boreholes and recorded with a digital data acquisition system. The hammer source experiments on the piers provided information about the seismic wave propagation velocities in the pier. The refraction experiments with the air gun had limited success due to lack of coupling between the incident wave and the cylindrical pier. Vertical velocity surveys were performed in order to obtain an estimate of seismic wave propagation velocities in the subbottom sediments. The direct arrival experiments provided data that indicated this method could, under certain conditions, detect changes in water bottom topography.
Relating Electrical Response and Petrophysical Properties of Sands Subjected to Stress Changes
Authors: Seabrook Brian C. , Boadu Fred K.
Published: September 2009

The spectral electrical responses (SER) and hydraulic properties of clean sands saturated with deionized water and subjected to varying stress levels in a laboratory environment are investigated and analyzed. A variation of the multi-Cole-Cole dispersion model that predicts the behavior of the SER of sands is suggested for the analysis. This dispersion model is described by circuit elements [Formula: see text], the bulk resistivity, chargeability [Formula: see text], time constant [Formula: see text], and exponent [Formula: see text], representing various conduction mechanisms. The values of [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], which describe the SER are directly affected by changes in the applied stress and the attendant changes in hydraulic properties: porosity and hydraulic conductivity. It is observed that changes in the hydraulic properties of the sands due to changes in the applied effective stress are related to the circuit parameters characterizing this model. In general, a decrease in porosity results in an increase in the relaxation time constant [Formula: see text]. The rate of increase in [Formula: see text] is higher for variable size sands than for monosize sands. The time constant is generally greater for larger monosize sands than for smaller monosize sands, and thus [Formula: see text] may be related directly to the mean grain size. Changes in the applied effective stress are shown to result in changes in the chargeability of the soils. The chargeability [Formula: see text] of the soil decreases with increases in hydraulic conductivity [Formula: see text] and porosity [Formula: see text]. Increases in [Formula: see text] and [Formula: see text] tend to increase the frequency dependence exponent [Formula: see text] of the soil.
Determining the Condition of Hot Mix Asphalt Specimens in Dry, Water-Saturated, and Frozen Conditions Using GPR
Authors: Liu Lanbo , Guo Tieshuan
Published: September 2009

A series of laboratory experiments were conducted to measure the dielectric constant of hot mix asphalt (HMA) pavement specimens in dry, water-saturated, and frozen conditions. We used a [Formula: see text] ground penetrating radar (GPR) system to measure the travel times for direct and reflected waves for computing the electromagnetic (EM) wave velocity. In conjunction with other information on geometry, void ratio, and composition, we computed the dielectric constants of 30 specimens. Our major conclusions are: (1) In general, EM wave velocity is highest in dry conditions, intermediate in frozen, and lowest in water-saturated conditions; (2) EM wave velocity increases slightly with the increase of void ratio for dry samples. In contrast, it decreases significantly with void ratio increase in water-saturated conditions. Correspondingly, the dielectric constant decreases noticeably with an increasing void ratio in dry conditions, and increases appreciably in saturated conditions, in the range of void ratio from zero to 6%; (3) The changes of EM velocity and dielectric constant for dry, saturated, and frozen conditions can be reasonably predicted by the complex refractive index model (CRIM) for porous media; (4) Variations in EM velocity and dielectric constant with respect to asphalt ratio implies that a low asphalt ratio corresponds with a high void ratio; and (5) The observed variations in EM velocity and dielectric constant can be attributed to the change of moisture content of an HMA specimen in different conditions.
Monitoring Carbon Dioxide Floods Using Electrical Resistance Tomography (ERT): Sensitivity Studies
Authors: Ramirez Abelardo L. , Newmark Robin L. , Daily William D.
Published: September 2009

We have conducted a numerical and physical modeling study to evaluate the sensitivity of electrical resistance tomography (ERT) to electrical resistivity changes caused by [Formula: see text] injection and sequestration in geologic reservoirs. We chose the Maljamar [Formula: see text] flood (pilot study) as a basis for our numerical modeling study. We also constructed physical models consisting of blocks of various materials inserted in a water tank to evaluate some of the conclusions of the numerical study. This study quantifies the effects of a variety of factors that affect the resolution and accuracy of the ERT method, under realistic conditions of scale, contrast, and measurement error. It considers scenarios where vertical arrays of point electrodes are used and where metal-cased boreholes are used as long electrodes. Long electrode tomographs provide information such as the shape, location, and lateral extent of the flood. When point electrode arrays or horizontal wells are available, the approximate vertical extent of the flood and coarse estimates of sequestered [Formula: see text] volume may be deduced. Results from physical models support trends observed in the numerical study. Based on this study, we suggest that the ERT method can help confirm the containment of [Formula: see text].
Energy and Soil-Moisture Effects on Nonlinear Deformation Associated with Near-Surface Seismic Reflection Sources
Authors: Malinowski Matthew S. , Baker Gregory S.
Published: September 2009

The ability to collect seismic-reflection data in the upper [Formula: see text] of the subsurface (ultrashallow seismic reflection: USR) is important because it offers an alternative to ground-penetrating radar in regions exhibiting high attenuation of electromagnetic signal. Previous work has demonstrated that the critical controllable factors in obtaining USR data are dense spatial sampling and high [Formula: see text] frequency content. The frequency content is strongly controlled by the characteristics of the sources used to generate the seismic energy. Qualitative experiments have indicated that the higher-energy near-surface seismic reflection projectile sources lack some of the high-frequency energy exhibited by smaller-energy sources. In addition, soil moisture content has been shown to be an important variable in the frequency content of data even if the same source is used. In both cases, the reduction in the frequency content of the data has been hypothesized to correlate with greater amounts of near-source, nonlinear deformation. A corollary of this hypothesis states that source energy and soil-moisture affect the amount of nonlinear deformation generated by near-surface seismic energy sources. As an initial test of this corollary, experiments have been conducted in a controlled laboratory setting to quantitatively determine the relationship between source energy, soil-moisture conditions, and the amount of near-source, nonlinear deformation. Projectile sources with different energy (ammunition) were fired into a sand pit having varied moisture content, and the resulting voids were filled with plaster. The volume of the casts (representing the most substantial region of nonlinear deformation) was then measured. Results indicate that source energy and soil moisture have a direct correlation with the amount of near-source, nonlinear deformation.
Reactivity of Cyclic (Alkyl)(amino)carbenes (CAACs) and Bis(amino)cyclopropenylidenes (BACs) with Heteroallenes: Comparisons with their N‐Heterocyclic Carbene (NHCs) Counterparts
Authors: Kuchenbeiser Glenn , Soleilhavoup Michele , Donnadieu Bruno , Bertrand Guy
Published: September 2009

Similarly to NHCs, CAACa and BACa react with CO2 to give the corresponding betaines. Based on the carbonyl stretching frequencies of cis‐[RhCl(CO)2(L)] complexes, the order of electron donor ability was predicted to be CAACa≈BACa>NHCs. When the betaines νasym(CO2) values are used, the apparent ordering is BACa>NHCs≈CAACa that indicates a limitation for the use of IR spectroscopy in the ranking of ligand σ‐donating ability. Although all carbenes react with carbon disulfide to give the corresponding betaines, a second equivalent of CS2 reacts with the BAC‐CS2 leading to a bicyclic thieno[2,3‐diamino]‐1,3‐dithiole‐2‐thione, which results from a novel ring expansion process. Surprisingly, in contrast to NHCs, CAACa does not react with carbodiimide, whereas BACa exclusively gives a ring expanded product, analogous to that obtained with CS2. The intermediate amidinate can be trapped, using the lithium tetrafluoroborate adduct of BACb as a carbene surrogate.
From the petroeconomy to the bioeconomy: Integrating bioenergy production with agricultural demands
Authors: Mathews John A.
Published: September 2009

Production of biomass for bioenergy generation, and in particular production of biologically derived liquid fuels, is attracting great interest as an alternative to the fossil fuel economy. Biofuels represent as yet only 1% of world agricultural output, but this small extension has triggered widespread fears, many now shown to be groundless, such as the fear that it was biofuels that drove up food prices in 2008. This perspective reviews the literature on the extent to which biofuel production can be integrated into agricultural production, taking a global view of the potential for land, water and other resources to be extended beyond current food, feed and fi ber applications. As opposed to the focus on negative impacts, there are benefi cial practices in biofuels that could be expected to propagate to agriculture more generally and have a positive impact on yields and practices. These include (1) promoting a shift from wasteful annual crops to perennials, particularly low‐input high‐diversity (LIHD) crops; (2) sequestering carbon in soil both organically and as biochar; (3) improving conservative water management practices; and (4) recycling resources. The possibilities of encouraging biofuel production (and biomass for bioenergy generally) in the tropical South, for consumption in the temperate North, based on certifi cation of such sustainable practices in the South, could be expanded if global trade in biofuels were liberalized. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd
Effects of pulsed magnetic field on the formation of magnetosomes in the Magnetospirillum sp. strain AMB‐1
Authors: Pan Weidong , Chen Chuanfang , Wang Xiaoke , Ma Qiufeng , Jiang Wei , Lv Jing , Wu Long‐Fei , Song Tao
Published: September 2009

Magnetotactic bacteria are a diverse group of microorganisms which possess one or more chains of magnetosomes and are endowed with the ability to use geomagnetic fields for direction sensing, thus providing a simple and excellent model for the study of magnetite‐based magnetoreception. In this study, a 50 Hz, 2 mT pulsed magnetic field (PMF) was applied to study the effects on the formation of magnetosomes in Magnetospirillum sp. strain AMB‐1. The results showed that the cellular magnetism (Rmag) of AMB‐1 culture significantly increased while the growth of cells remained unaffected after exposure. The number of magnetic particles per cell was enhanced by about 15% and slightly increased ratios of magnetic particles of superparamagnetic property (size <20 nm) and mature magnetosomes (size >50 nm) were observed after exposure to PMF. In addition, the intracellular iron accumulation slightly increased after PMF exposure. Therefore, it was concluded that 50 Hz, 2 mT PMF enhances the formation of magnetosomes in Magnetospirillum sp. strain AMB‐1. Our results suggested that lower strength of PMF has no significant effects on the bacterial cell morphologies but could affect crystallization process of magnetosomes to some extent. Bioelectromagnetics 31:246–251, 2010. © 2009 Wiley‐Liss, Inc.
Structural transition from dimeric to tetrameric i‐motif, caused by the presence of TAA at the 3′‐end of human telomeric C‐rich sequence
Authors: Kaushik Mahima , Prasad Manoj , Kaushik Shikha , Singh Anju , Kukreti Shrikant
Published: September 2009

Widely dispersed in genomic DNA, the tandem C‐rich repetitive stretches may fold below physiological pH, into i‐motif structures, stabilized by C·C+ pairing. Herein, structural status of a 9‐mer stretch d(CCCTAACCC), [the truncated double repeat of human telomeric sequence], and its extended version, comprising of additional TAA segment at the 3′‐end, representing the complete double repeat d(CCCTAACCCTAA), has been investigated. The pH dependent monophasic UV‐melting, Gel and CD data suggested that while the truncated version adopts a bimolecular i‐motif structure, its complete double repeat (12‐mer) sequence exists in two (bimolecular and tetramolecular) forms. A model is proposed for the tetramolecular i‐motif with conventional C·C+ base pairs, additionally stabilized by asymmetric A·A base pairs at the −3′ TAA flanking ends and Watson–Crick A·T hydrogen bonding between intervening bases on antiparallel strands. Expanding the known topologies of DNA i‐motifs, such atypical geometries of i‐motifs may have implications in their recognition by proteins. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 150–160, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Consumer decision making in low‐income families: The case of conflict avoidance
Authors: Hamilton Kathy
Published: September 2009

This paper explores consumer decision making in low‐income families. The focus is on the issue of conflict avoidance within the family when making consumption choices. Whereas previous studies have focused on conflict resolution strategies, this paper considers the ways in which families prevent conflict from arising in the first instance. These include individual control in purchasing and budgeting decisions, giving in to the requests of children and ensuring open communication about the family's financial situation. Importantly, the connections between the poverty narrative and the family decision making narrative are considered as the decision making strategies employed are not only aimed at avoiding conflict but also making experiences of poverty more manageable.

Copyright © 2009 John Wiley & Sons, Ltd.
Consequences of customer powerlessness: Secondary control
Authors: Bunker Matthew , Ball A. Dwayne
Published: September 2009

This research investigated the consequences of powerlessness when consumers experience service failure with a company that has high‐exit barriers. The specific consequences investigated were three types of secondary control, which are grudge‐holding, avoidance (predictive avoidance), and retaliation desire. These secondary control coping strategies highlight consumers' ability to control their personal behaviors and thoughts, even when they cannot completely control the outcomes of a situation. A qualitative study, followed by a scenario‐based survey and structural equation model, suggest that the primary direct consequences of powerlessness in commercial relationships are grudge‐holding and predictive avoidance, and that both predictive avoidance and a desire to retaliate are further consequences of grudge‐holding. The results of this research underscore the importance of understanding the role of powerlessness and its consequences in consumer–firm relationships.

Copyright © 2009 John Wiley & Sons, Ltd.
Ultrahigh‐Throughput FACS‐Based Screening for Directed Enzyme Evolution
Authors: Yang Guangyu , Withers Stephen G.
Published: September 2009

Directed enzyme evolution has proven to be a powerful tool for improving a range of properties of enzymes through consecutive rounds of diversification and selection. However, its success depends heavily on the efficiency of the screening strategy employed. Fluorescence‐activated cell sorting (FACS) has recently emerged as a powerful tool for screening enzyme libraries due to its high sensitivity and its ability to analyze as many as 108 mutants per day. Applications of FACS screening have allowed the isolation of enzyme variants with significantly improved activities, altered substrate specificities, or even novel functions. This review discusses FACS‐based screening for enzymatic activity and its potential application for the directed evolution of enzymes, ribozymes, and catalytic antibodies.
Distal balloon deflation technique: A new method to facilitate entry of balloon catheter, stent, and guiding catheter to distal lesion
Authors: Ashikaga Takashi , Sakurai Kaoru , Satoh Yasuhiro
Published: September 2009

We occasionally encountered difficult cases of balloon and stent delivery to the distal lesion because of narrow stent strut, severe calcification, or tortuosity of the proximal section. We describe a new technique to deliver balloon, stent, and guiding catheter to the distal lesion using a distal balloon deflation. This technique offers a potential alternative for cases in which the delivery of balloon and stent is difficult. © 2009 Wiley‐Liss, Inc.
Ever heard of the obturator vein?
Authors: Brown Stephen C. , Gewillig Marc
Published: September 2009

We report a complication related to advancement of a large diameter long sheath in the obturator vein. In an adult with a previously thrombosed femoral vein, the obturator vein was inadvertently cannulated. During percutaneous pulmonary valve implantation, the Ensemble® delivery system could not be advanced after repositioning attempt. The obturator vein had been perforated and sheath was coiled up in the pelvis leading to a retroperitoneal pelvic hematoma. Continuity of the vein was established using two self‐expanding covered stents. The obturator vein runs dorsally and joins the inferior caval vein at a very acute angle posterior in the pelvis, creating a corner in which stiff catheters or sheaths may get entrapped. © 2009 Wiley‐Liss, Inc.
Acute compartment syndrome of the forearm that occurred after transradial intervention and was not caused by bleeding or hematoma formation
Authors: Araki Tadashi , Itaya Hideki , Yamamoto Masato
Published: September 2009

Recently, transradial angiography and intervention have been performed with high success rates and low rates of vascular complications. The incidence of compartment syndrome after the transradial approach seems to be very low. However, bleeding in the arm can occur and may lead to the devastating complication of compartment syndrome of the forearm, which if not treated early, can evolve into a disability of the arm. In fact, most cases of such complications are caused by guidewire‐ or catheter‐induced damage to small arterial branches that are considerably proximal to the puncture site. However, we encountered a case of compartment syndrome that was not caused by bleeding or hematoma formation and required urgent fasciotomy for its treatment. The forearm wounds were left open to allow the edema to resolve and closed after 1 week. The patient recovered and was discharged, with full movement of his forearm and hand. We suspect that an arterial spasm induced by the radial sheath or catheter resulted in ischemia of the forearm muscles. To our knowledge, this is the first reported case in which acute compartment syndrome of the forearm occurred after transradial intervention and was not due to bleeding or hematoma formation. © 2009 Wiley‐Liss, Inc.
A challenging case of dislodged stent retrieval with the use of Goose neck snare kit
Authors: Yang Soon Chao , Chong Eric , Sangiorgi Giuseppe M.
Published: September 2009

We report a case of successful transfemoral retrieval of a dislodged and mechanically distorted coronary stent from the right coronary artery in a middle age woman. The distorted stent was recovered via upsizing of her femoral arterial sheath and the use of a microsnare. The procedure was further complicated by significant right common femoral artery dissection, which was treated with percutaneous transluminal angioplasty from her contralateral femoral artery. The patient recovered well and was discharged the following day. © 2009 Wiley‐Liss, Inc.
Trifurcation stenting using two guide catheters
Authors: Puri Aniket , Sethi Rishi , Puri Vijay K.
Published: September 2009

Trifurcating coronary artery disease is a complex atherosclerotic process involving the origin of one or more of three side branches arising from a main trunk. The approach to treat trifurcation lesions has not been standardized. We describe a technique to percutaneously treat this lesion using routine day‐to‐day hardware and a unique two guide catheter technique. © 2009 Wiley‐Liss, Inc.
Synthesis and Studies of the Visible‐Light Photocatalytic Properties of Near‐Monodisperse Bi‐Doped TiO2 Nanospheres
Authors: Li Haiyan , Wang Dejun , Wang Ping , Fan Haimei , Xie Tengfeng
Published: September 2009

Near‐monodisperse Bi‐doped anatase TiO2 nanospheres with almost uniform diameters in the range of 117 to 87 nm were prepared simply by introducing different amounts of bismuth nitrate pentahydrate into the reaction system and subsequent calcinations. X‐ray diffraction, UV‐visible diffuse reflectance spectra, and X‐ray photoelectron spectroscopy confirm that the doped ions substitute some of the lattice titanium atoms, and furthermore, Bi3+ and Bi4+ ions coexist. All the Bi‐doped TiO2 samples show much better photocatalytic activity than pure TiO2 in the degradation of rhodamine B (RhB) under the irradiation of visible light (λ>420 nm), and, interestingly, it was found that the degradation mechanism is different from the conventional one, which has already been reported elsewhere. The detailed mechanism is discussed in this article.
Synthesis, Structure and Reactivity of Disila‐ and Distanna ansa Half‐Sandwich Complexes of Molybdenum and Tungsten
Authors: Bera Holger , Braunschweig Holger , Dörfler Rainer , Hammond Kai , Oechsner Andreas , Radacki Krzysztof , Uttinger Katharina
Published: September 2009

We present the synthesis and characterization of disila‐ and distanna ansa half‐sandwich complexes of Group 6 transition metals. These compounds exhibit high ring strain within the ansa bridge, which is the key factor for the insertion of elemental chalcogens.
Polyfluorophore Labels on DNA: Dramatic Sequence Dependence of Quenching
Authors: Teo Yin Nah , Wilson James N. , Kool Eric T.
Published: September 2009

We describe studies carried out in the DNA context to test how a common fluorescence quencher, dabcyl, interacts with oligodeoxynucleoside fluorophores (ODFs)—a system of stacked, electronically interacting fluorophores built on a DNA scaffold. We tested twenty different tetrameric ODF sequences containing varied combinations and orderings of pyrene (Y), benzopyrene (B), perylene (E), dimethylaminostilbene (D), and spacer (S) monomers conjugated to the 3′ end of a DNA oligomer. Hybridization of this probe sequence to a dabcyl‐labeled complementary strand resulted in strong quenching of fluorescence in 85 % of the twenty ODF sequences. The high efficiency of quenching was also established by their large Stern–Volmer constants (KSV) of between 2.1×104 and 4.3×105 M−1, measured with a free dabcyl quencher. Interestingly, quenching of ODFs displayed strong sequence dependence. This was particularly evident in anagrams of ODF sequences; for example, the sequence BYDS had a KSV that was approximately two orders of magnitude greater than that of BSDY, which has the same dye composition. Other anagrams, for example EDSY and ESYD, also displayed different responses upon quenching by dabcyl. Analysis of spectra showed that apparent excimer and exciplex emission bands were quenched with much greater efficiency compared to monomer emission bands by at least an order of magnitude. This suggests an important role played by delocalized excited states of the π stack of fluorophores in the amplified quenching of fluorescence.
Bipyridinium Array‐Type Porous Polymer Displaying Hydrogen Storage, Charge‐Transfer‐Type Guest Inclusion, and Tunable Magnetic Properties
Authors: Yao Qing‐Xia , Pan Long , Jin Xu‐Hui , Li Jing , Ju Zhan‐Feng , Zhang Jie
Published: September 2009

A multifunctional pillared‐layer porous coordination polymer, {[Mn2(Bpybc)(ox)2]⋅8 H2O}n, has been constructed based on a flexible viologen derivative, 1,1′‐bis(4‐carboxybenzyl)‐4,4′‐bipyridinium dichloride (H2BpybcCl2), and an oxalate (ox) coligand. Single‐crystal X‐ray analysis reveals that the compound possesses multichannels with dimensions of about 6.1×6.6 Å along the [110] and [−110] directions and 4.2×7.6 Å along [100], and a void space of about 41.4 %. Hydrogen adsorption measurements at 77 K and 1 atm indicate that the compound exhibits a hydrogen uptake of 0.71 wt %. Owing to the incorporation of bipyridinium acceptor units, the compound can selectively accommodate aromatic donors into its nanosized pores based on charge‐transfer interactions in an elastic way, and afford a specific color to different guests. Furthermore, the effect of perturbation exerted by the guest molecules on its magnetic properties has been investigated. The results indicate that the donor inclusion has little effect on its antiferromagnetic behavior, whereas dehydration of the compound decreases the strength of the magnetic exchange couplings and results in a change of the antiferromagnetic transition temperature from 14.7 to 9.8 K.
Chemoselective Boron–Carbon Bond Cleavage by Hydroboration of Borirenes
Authors: Braunschweig Holger , Herbst Thomas , Radacki Krzysztof , Frenking Gernot , Celik Mehmet Ali
Published: September 2009

We report on the hydroboration of 1‐[bis(trimethylsilyl)amino]‐2,3‐diethylborirene (3) with 9‐borabicyclo[3.3.1]nonane (9‐BBN), which led through ring‐opening to an amino(vinyl)borane. The viscous borane was subsequently converted into a crystalline borate on treatment with MeLi. Both compounds were fully characterized by multinuclear NMR spectroscopy and in case of the latter by single‐crystal X‐ray diffraction analysis. To elucidate the reaction mechanism of the unexpected boron‐carbon bond cleavage, DFT calculations of energy minima and transition states for the hydroboration were carried out.
Low‐Molecular‐Weight Analogues of the Soluble Methane Monooxygenase (sMMO): From the Structural Mimicking of Resting States and Intermediates to Functional Models
Authors: Siewert Inke , Limberg Christian
Published: September 2009

The active centre of sMMO contains a diiron core ligated by histidine and glutamate residues, which is capable of catalysing a remarkable reaction: the oxidation of methane with O2 yielding methanol. This review describes the results of efforts to prepare low‐molecular‐weight analogues of this active site directing towards 1) the assignment of the spectroscopic signatures identified for certain intermediates of the sMMO catalytic cycle to structural features and 2) the synthesis of molecular compounds that can mimic the reactivity. The historical development of the model chemistry, which is subdivided into structural and functional mimicking, is illustrated and achievements reached so far are highlighted.
Catalytic Conjugate Additions of Geminal Bis(sulfone)s: Expanding the Chemistry of Sulfones as Simple Alkyl Anion Equivalents
Authors: Landa Aitor , Puente Ángel , Santos J. Ignacio , Vera Silvia , Oiarbide Mikel , Palomo Claudio
Published: September 2009

The value of cyclic gem‐bis(sulfone) 4 as a simple alkyl nucleophile equivalent in catalytic C–C bond‐forming reactions is demonstrated. The 1,4‐type nucleophilic additions of bis(sulfone) 4 to α,β‐unsaturated ketones take place by assistance of catalytic guanidine base. On the other hand, pyrrolidines are able to catalyze the conjugate addition of 4 to both enones and enals, likely by means of iminium ion activation. Upon exploration of the best chiral pyrrolidine catalyst, it has been found that the addition of 4 to enals catalyzed by diphenylprolinol silyl ether 10 proceeds with very high enantioselectivity (β‐aryl‐substituted enals >95 % ee; β‐alkyl substituted enals up to 94 % ee; ee=enantiomeric excess). Further reductive desulfonation of adducts gives rise to the corresponding β‐methyl aldehydes, as well as the derived alcohols, acetals, and methyl esters after simple (Mg, MeOH) well‐established protocols. Application of the procedure to the synthesis of biologically relevant phenethyl building blocks is shown. Most interestingly, α‐alkylation of initially obtained bis(sulfone) adducts can be done even with less reactive alkylating reagents, such as long linear‐chain or branched‐chain alkyl halides. Accordingly, upon the desulfonation process, a general, experimentally simple and highly enantioselective access to β‐branched aldehydes, alcohols, or esters is possible. Further exploration of the method includes the use of chiral α,β‐unsaturated aldehydes derived from citronellal as the Michael acceptor partners. In these instances, the sense of the conjugate addition of 4 is controlled by the chirality of the pyrrolidine catalyst, thus allowing for a stereochemically predictable access to 1,3‐dimethyl arrays, such as those present in deoxygenated polyketide‐type natural products. The intramolecular variation of this technology by using doubly unsaturated aldehyde–ester 22 illustrated the site selectivity of the procedure and its potential for tandem processes leading to highly substituted polycyclic systems, such as 24.
ChemInform Abstract: Ab initio Structure Determination of Mg10Ir19B16.
Authors: Xu Qiang , Klimczuk T. , Gortenmulder Ton , Jansen Jacob , McGuire M. A. , Cava R. J. , Zandbergen Henny W.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Co0.50VOPO4·2H2O.
Authors: Meng Lianxia , Ma Yuping , Zhang Xiaoliang , Xu Yan
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Frustrated Orders in the Perovskite (Bi0.5Sr0.5)CrO3.
Authors: Ortega‐San‐Martin Luis , Williams Anthony J. , Storer Alistair , Attfield J. Paul
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mechanistic Study of LiNH2BH3 Formation from (LiH)4+NH3BH3 and Subsequent Dehydrogenation
Authors: Lee Tae Bum , McKee Michael L.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Water Photooxidation by Smooth and Ultrathin α‐Fe2O3 Nanotube Arrays.
Authors: Mohapatra Susanta K. , John Shiny E. , Banerjee Subarna , Misra Mano
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Diatomic Dication PO2+.
Authors: Revesz Agnes , Sztaray Balint , Schroeder Detlef , Franzreb Klaus , Fiser Jiri , Price Stephen D. , Roithova Jana
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Quaternary Alloy Semiconductor Nanobelts with Bandgap Spanning the Entire Visible Spectrum.
Authors: Pan Anlian , Liu Ruibin , Sun Minghua , Ning Cun‐Zheng
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Atom‐Transfer Radical Addition of α‐Iodo Esters to 1‐Alkynyl Sulfides.
Authors: Imoto Junichi , Sato Akinori , Yorimitsu Hideki , Oshima Koichiro
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solvent‐Free Stobbe Condensation: A Green Approach.
Authors: Banerjee Shubhra , Tayde Ravibabu A. , Sharma Bhagyashree D.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Use of 1,2‐O‐Isopropylidene‐α‐D‐xylofuranose as a Chiral Auxiliary in Asymmetric Cyclopropanation Reactions.
Authors: Vega‐Perez Jose M. , Perinan Ignacio , Iglesias‐Guerra Fernando
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Hydroxylative Phenol Dearomatization Through in situ Generation of Iodanes from Chiral Iodoarenes and m‐CPBA.
Authors: Quideau Stephane , Lyvinec Gildas , Marguerit Melanie , Bathany Katell , Ozanne‐Beaudenon Aurelie , Buffeteau Thierry , Cavagnat Dominique , Chenede Alain
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium(II)‐Catalyzed Selective Oxidation of α,β‐Unsaturated Aldehydes to α,β‐Unsaturated Carboxylic Acids with Hydrogen Peroxide.
Authors: Kon Yoshihiro , Imao Daisuke , Nakashima Takuya , Sato Kazuhiko
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium‐Catalyzed Cyanation of Carbon—Carbon Triple Bonds under Aerobic Conditions.
Authors: Arai Shigeru , Sato Takashi , Koike Yuka , Hayashi Michino , Nishida Atsushi
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Iron‐Catalyzed Cross‐Aldol Reactions of ortho‐Diketones and Methyl Ketones.
Authors: Li Haijun , Li Wenjuan , Li Zhiping
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Hydroxyl‐Directed Trifluoromethylation of Hydrazones.
Authors: Dilman Alexander D. , Levin Vitalii V. , Belyakov Pavel A. , Korlyukov Alexander A. , Struchkova Marina I. , Tartakovsky Vladimir A.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sequential Hiyama Coupling/Narasaka Acylation Reaction of (E)‐1,2‐Disilylethylene: Rapid Assembly of α,β‐Unsaturated Carbonyl Motifs.
Authors: Thiot Carine , Mioskowski Charles , Wagner Alain
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium‐Catalyzed Multicomponent Aminocarbonylation of Aryl or Heteroaryl Halides with [Mo(CO)6] and Aryl‐ or Heteroarylamines Using Conventional Heating.
Authors: Begouin Agathe , Queiroz Maria‐Joao R. P.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: One‐Pot Etherification of Ketones and Aldehydes with Organic Halides Using Sodium Hydride as a Reductant
Authors: Meng Qingwei , Gong Bin , Hui Chuang , Gao Zhanxian
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Convenient and Efficient Triton B‐Mediated Synthesis of Functionalized Oxime Ethers.
Authors: Meshram H. M. , Eeshwaraiah B. , Sreenivas M. , Aravind D. , Sundar B. Syama , Yadav J. S.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1,2,3‐Triazole‐Strapped Calix[4]pyrrole: A New Membrane Transporter for Chloride.
Authors: Fisher Matthew G. , Gale Philip A. , Hiscock Jennifer R. , Hursthouse Michael B. , Light Mark E. , Schmidtchen Franz P. , Tong Christine C.
Published: September 2009

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 of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.