bluuebunny/crossref_metadata_2025 huggingface dataset:
Nasofrontal abscess following rhinoplasty
Authors: Barat Michael , Shikowitz Mark J.
Published: October 2006

Infections are the most common objective complication following rhinoplasty. They may remain localized, extend intracranially, or result in generalized septicemia. The most common infections involve the skin and subcutaneous tissues of the nose. We report an uncommon case of nasofrontal abscess following a rhinoplasty that required aggressive surgical and medical treatment.
Multichannel cochlear implantation in obliterated cochleas using the gantz procedure
Authors: Steenerson Ronald L. , Gary Lucinda B.
Published: October 2006

Gantz, et al. reported two patients with extensive cochlear ossification in which cochlear implantation was done with a Nucleus 22‐Channel Cochlear Implant after extensive cochlear drill‐out. One of the patients did well with 20 functioning electrode pairs. We report an additional three patients with extensive cochlear ossification who received Nucleus 22‐Channel Cochlear Implants. All three patients had extensive cochlear drill‐out as described by Gantz, et al. All three patients have use of all 21 electrode pairs with amperages typical of conventional implantation in two of the three and slightly increased levels in the third. Extensive bilateral cochlear ossification does not seem to be an absolute contraindication for multichannel cochlear implantation.
The effect of decongestive nosedrops on human respiratory mucosa in Vitro
Authors: Berg Øystein H. , Lie Kathrine , Steinsvåg Sverre K.
Published: October 2006

The aim of this study was to investigate the morphological effects of decongestive drops and sprays on human respiratory mucosa in vitro. Precultured fragments of adenoid tissue in a specially designed tissue culture system were exposed to decongestive preparations for 10 minutes once a day for 10 days. Tissue exposed to preparations preserved with benzalkonium chloride and tissue exposed to benzalkonium chloride alone underwent severe morphological alterations. Unpreserved decongestive substances did not have this effect. Benzalkonium chloride is a well‐documented toxic substance in several respects. Supported by previous studies, it may seem unfortunate to use it as an additive in decongestive preparations.
Gene transfer into human thyroid follicular cells
Authors: O'Malley Bert W. , Adams R. Mark , Sikes Michael L. , Ledley Fred D.
Published: October 2006

The authors established a means of effective gene transfer into human thyroid follicular cells via retroviral‐mediated mechanisms. Using specific harvest and culture techniques, we investigated the selection of human thyroid cells in serum‐free media. Normal adult human thyroid tissue was obtained after thyroidectomy from fresh specimens sent for frozen‐section analysis. Follicular cells were harvested and grown in hormonally defined, serum‐free media to prevent fibroblast growth with selection for differentiated function assessed by immunohisto‐chemical staining for thyroglobulin. The efficiency of gene transfer into human thyroid cells was compared between the zen‐β‐gal and LNL6 retroviral vectors. The zen‐β‐gal retrovirus encodes the product β‐galactosidase, and gene expression was demonstrated by histochemical staining in 0.1% to 1% of the cells. An improved efficiency of 2% to 3% transduction was demonstrated using the LNL6 vector which carries the gene for neomycin resistance (NEO‐R). Polymerase chain reaction (PCR) identification of the integrated proviral sequence (NEO‐R gene) with Southern blot confirmation was used to quantitate LNL6 transductions and compare confluent versus actively dividing cell cultures. Follicular cell gene therapy has significant potential for treating congenital or acquired diseases of the thyroid as well as disorders of circulating proteins such as diabetes, hypopituitarism, and hemophilia. The ability to culture human follicular cells and perform effective gene transfer is paramount in the eventual realization of thyroid gene therapy.
Crystal-Size Dependence of Illite-Smectite Isotope Equilibration with Changing Fluids
Authors: Williams Lynda B. , Hervig Richard L.
Published: October 2006

Differences in equilibration rates among crystals of different sizes may be used to deduce paleofluid changes over time if the crystal-growth mechanism is known. To explore isotopic equilibration rates as a function of illite growth, we studied B-isotope changes during illitization of smectite. Montmorillonite (<2.0 µm SWy-1, K saturated) was reacted with aqueous boric acid (1000 ppm B) at 300°C, 100 MPa in sealed Au capsules (1:1 fluid:mineral ratio). The initial fluid was 0‰ (NBS 951 standard) but after R1 ordering occurred (65 days of reaction) the fluid was changed to −7‰ in order to examine the rate of isotopic re-equilibration. Samples were taken intermittently throughout the experiment. Each aliquot was NH4 exchanged and size separated into fine (<0.2 µm), medium (0.2–2.0 µm) and coarse (>2.0 µm) fractions. The isotopic composition of B in the tetrahedral sheet was then measured for comparison with the predicted equilibrium values.

The fine fraction showed equilibrium isotope ratios within 10 days, indicating that small, newly nucleated crystals precipitate in equilibrium with the fluid under supersaturated, closed conditions. These fine-fraction minerals did not re-equilibrate when the fluid was changed. The medium fraction gradually equilibrated with the initial fluid as illite grew to values >50%, but did not re-equilibrate with the later fluid. The coarse fraction was slow to begin recrystallization, perhaps due to dissolution kinetics of large crystals or the presence of detrital contaminants. However, it showed the fastest rate of isotopic change with crystal growth after R1 ordering. We conclude that at 300°C, the initial B–O bonds formed in illite are stable, and isotopic re-equilibration only occurs on new crystal growth. Therefore, different isotope ratios are preserved in different crystal size fractions due to different rates of crystal growth. Large crystals may reflect equilibrium with recent fluid while smaller crystals may retain isotope compositions reflecting equilibrium with earlier fluids.
Geology, Mineralogy and Origin of Clay Minerals of the Pliocene Fluvial-Lacustrine Deposits in the Cappadocian Volcanic Province, Central Anatolia, Turkey
Authors: Gürel Ali , Kadır Selahattın
Published: October 2006

The Güzelöz-İncesu Plateaus are situated in the central and eastern parts of the Cappadocian volcanic province (central Anatolia). This province contains many ignimbrite levels, andesite, basalt intercalated with several paleosols, calcrete, carbonate, fluvial sediments, diatomaceous clayey sediments and pyroclastic sedimentary levels. The presence of mottling, sesquioxide, root traces, rhizoids and burrows in continuous, finely bedded and laminated sediments, paleosols, calcrete, the occurrence of bone- and teeth-bearing reworked pyroclastic materials, and the description of the lithofacies in the study area indicate fluvial and shallow-lake environments. These environments are dominated by smectite and illite, with traces of kaolinite, associated mainly with plagioclase, K-feldspar, quartz, calcite, opal-CT, pyroxene (diopside, rare hypersthene), and locally trace amounts of gypsum and sepiolite. Smectite predominates in paleosols and calcrete units, and generally increases upwards in the profiles, coinciding with a gradual increase in the degree of alteration. Partial to complete alteration of plagioclase, K-feldspar, pyroxene and partial devitrification of glass-shard particles in pyroclastic rocks, development of microsparitic to sparitic cement comprising euhedral rhombic calcite crystals between irregular clay nodules in paleosol and calcrete samples, along with the occurrence of dogtooth-type sparitic crystals in fractures, desiccation cracks and geopetal-type fenestrae, indicate alternating periods of drought and wet, resulting in the development of paleosols and calcretes. Micromorphological development of spongiform smectite on mainly relict feldspar and, locally, on glass shards, indicates an authigenic origin, whereas illite formed either authigenically or by conversion of smectite to illite-smectite.
The Smectite-to-Disordered Kaolinite Transition in a Tropical Soil Chronosequence, Pacific Coast, Costa Rica
Authors: Fisher G. Burch , Ryan Peter C.
Published: October 2006

Soils developed on Quaternary fluvial fill terraces in the humid tropics of Costa Rica display progressive changes in mineral assemblage, chemical composition and particle size with age. Clay minerals from B horizons of active floodplains are predominantly smectite with lesser amounts of disordered kaolinite. B horizons in 5 to 10 ka soils consist of sub-equal amounts of smectite and disordered kaolinite, and soils on 37–125 ka terraces consist of disordered kaolinite with only traces of smectite. The composition of the smectite, as determined by EDX scans of smectite-rich pore space, is [(Mg0.2,Ca0.1)(Fe0.6Al1.4)(Si3.6Al0.4)O10(OH)2], consistent with ferruginous beidellite.

Bulk mineral assemblage varies from a smectite-plagioclase-augite-quartz-magnetite assemblage in ⩽ 10 ka terrace soils to a disordered kaolinite-goethite-hematite-quartz-magnetite assemblage in ⩾37 ka terrace soils. Leaching results in rapid loss of soluble base cations and residual concentration of Ti and Zr indicates mass losses of ∼50% by chemical denudation by 125 ka. Plots of terrace age vs. various measures of clay mineralogy, chemical composition, and particle size produce parabolic curves consistent with rapid chemical weathering pre-37 ka and slower to imperceptible rates of change from 37 to 125 ka. For some pedogenic properties, particularly particle size and concentrations of base cations and Zr, soils appear to reach steady-state conditions within 37 ka.

These results were applied to interpretation of landscape evolution in this tectonically active region by: (1) facilitating identification of two Holocene (5 ka and 10 ka) terraces on the Esterillos Block 5–30 m above sea level (masl), and two Pleistocene terraces ⩾ 125 ka on the Parrita Block 30 masl, and, in turn, (2) documenting uplift rates as high as 4.4 m/ka between 37 and 10 ka on the Esterillos Block, and as low as 0.1 m/ka over the past 125 ka on the adjacent Parrita Block. These findings are consistent with previous work indicating that the subduction of anomalous bathymetric features at the Middle America Trench is having a significant impact on fore-arc dynamics and topography over relatively short geological time periods and spatial scales.
Fuzzy Phase Diagrams of Clay Minerals
Authors: Varadachari Chandrika
Published: October 2006

This paper presents a novel concept in the thermodynamic derivation of phase diagrams for clay minerals that incorporates fuzzy transition zones. This new technique yields phase diagrams that have graded (fuzzy) zones of mineral occurrences and includes compositional variability within mineral groups. For the construction of these diagrams, 170 minerals belonging to nine different subgroups were used, based on a fuzzy mathematical description of their ‘grades’ or ‘belonging-ness’. Standard free energies of formation of all the minerals were derived and all possible pairs of mineral equilibria were evaluated. Relative intensities of mineral occurrences were determined and membership values of each type of mineral at various zones in a 2D or 3D space were graphically represented. Computations and graphical representations were carried out using programs developed in Mathematica. Diagrams were derived for 25°C, 1 bar with a solution phase containing Si(OH)4, K+, Na+, H+, Ca2+ and Mg2+ under conditions of gibbsite, goethite and ferrous oxide saturation. The resulting diagrams, unlike conventional phase diagrams, show multimineral assemblages, with varying occurrences of different minerals and provide a realistic representation of clay mineral occurrences formed by surface geochemical processes. They show that on the Earth’s surface, only montmorillonite can almost completely predominate the inorganic phase followed by kaolinite, illite and beidellite. Nontronite, glauconite, celadonite and vermiculite would not be neoformed in substantial amounts. A general conformity of derived phase equilibria with experimentally observed equilibria is also observed.
Preprosthetic Periodontal Surgery in the Proximal Area With Modification of the COL Area: Results Following the Reestablishment of the Contact Point
Authors: Papalexiou Vula , Novaes Arthur B. , Macedo Guilherme O. , Luczyszyn Sonia Mara , Muglia Valdir A.
Published: October 2006

Background: Anatomic characteristics of interproximal areas are dependent on the anatomy, position, and proximal contact of adjacent teeth. The objective of this study was to investigate the influence of the reestablishment of the interproximal contact following the restorative alveolar interface (RAI) procedure on the interproximal gingival COL and formation of the interdental gingival papilla.

Methods: Six mongrel dogs received bilateral apically positioned flaps, crown lengthening, and the RAI procedure on the maxillary fourth bicuspid and first molar. After 2 weeks, in a randomized manner, one side was prepared to receive metallic crowns and the opposite side remained as the control. The crowns were cemented at the 4‐week postoperative period, and the dogs were sacrificed after another 4 weeks, totaling a period of 4 weeks with the full crowns in position and a total of 8 postoperative weeks. Histologic specimens were stained with hematoxylin and eosin and Mallory dyes. Sections 6 μm thick were obtained in a bucco‐lingual plane allowing ample visualization of the interproximal area.

Results: Clinical measurements revealed that, in the restored sides, four animals had complete fill of the interdental spaces with gingival papilla, whereas the other two dogs had a distance from the contact point to the tip of papilla varying from 0.02 to 0.021 mm. In the control group, papillae were totally reepithelialized with keratinized epithelium and a convex form. The epithelium completely covered the connective tissue and showed both epithelial projections and surface desquamation. On the test group, despite the presence of the prosthesis, the COL morphology modified by preprosthetic surgery was not altered, presenting a convex papilla with a triangular form and with a keratinized epithelium. Additional histologic characteristics were the same as found in the control group.

Conclusion: Based on the results of this study, the reestablishment of the contact point does not revert what was obtained with the RAI procedure; the interproximal tissues remain convex and keratinized.
Chromium and nickel toxicity during the biotreatment of high ammonia landfill leachate
Authors: Harper Susan C. , Manoharan Ramanathan , Mavinic Donald S. , Randall Clifford W.
Published: October 2006

Two nitrification‐denitrification systems were used to determine the possible inhibitory and/or toxic effects of supplemental chromium and nickel addition to the nitrification‐denitrification process in the treatment of a relatively high ammonia, low biodegradable carbon, municipal landfill leachate. Results indicated that chromium (Cr+3) and nickel (Ni+2) caused inhibitory effects to the system at soluble concentrations of approximately 0.30 and 0.70 mg/L, respectively. Chromium affected both the nitrification and denitrification process, whereas nickel impaired only the nitrification performance; denitrification was unaffected at the nickel concentrations used. The failures were believed to be due to either the soluble metal levels themselves or the buildup of metals in the solids, although lack of long‐term acclimation cannot be ruled out. No phosphorus deficiency was noted in either case. This ruled out the possibility of system failures due to lack of bioavailable phosphorus, as reported with zinc in the early stages of this study.
Oxygen transfer limitation in a respirometer
Authors: Li Kuyen Y. , Zhang Yuebo B.
Published: October 2006

The oxygen uptake process in a respirometer was analyzed by a mathematical model consisting of oxygen transfer accompanied with oxygen consumption reaction. The criterion to avoid an oxygen‐transfer limitation was derived on the basis of the ratio of the maximum biochemical reaction rate to the maximum possible oxygen‐transfer rate. The maximum biochemical reaction is described by the first‐order rate equation, whereas the maximum possible oxygen‐transfer rate is calculated by multiplying the oxygen‐transfer coefficient with the solubility of oxygen in water. An oxygen‐transfer coefficient in a respirometric reactor was estimated as 1.8 h−1, by using the model analysis of an oxygen uptake data from the same reactor. A simplified criterion for a respirometer without oxygen‐transfer limitation is then obtained as XS ≪ 16.51/K1 where X and S represent concentration of biomass and substrate, respectively, and K1 is the first‐order rate constant, (L/mg VSS)/h.
An empirical study of nitrogen dynamics in lakes
Authors: Hellström Thomas
Published: October 2006

The parameters determining the annual balances of nitrogen (N) and the concentrations of total N in lakes were analyzed. This was carried out by the use of multiple regression analyses on data from a number of northern temperate lakes with a hydraulic detention time of 0.25 yr or more. The result indicated that the removal of N in a lake, which in most cases is dominated by denitrification, seems to be controlled by organic matter. If no major N fixation is taking place, the concentration of total N in the epilimnion during summer is proportional to the load of N and inversely proportional to the concentration of total P or chlorophyll a. For some lakes N fixation is taking place. The increase in total N due to N fixation was found to be proportional to the concentration of total P reduced by a fraction of the estimated N concentration without any fixation. For most lakes, the effect of N fixation is to balance the N content with the P content, which means that the algal biomass is limited by the P content. A ratio of the total concentrations N/P less than approximately 10 indicates a rate of denitrification exceeding the capacity of N fixation. N is not balanced with P, and the algae is controlled by N.
A correction factor for predicting the multicomponent adsorption of air stripper offgas
Authors: O'Connor Thomas P. , Mueller James A. , Mahony John D. , Di Toro Dominic M.
Published: October 2006

Air stripping is a common way to remove volatile organic compounds (VOCs) from drinking water with the off‐gas from air stripping often requiring treatment. The removal of the VOCs from the off‐gas can be achieved by adsorbing the VOCs onto granulated activated carbon (GAC). When the capacity for GAC to adsorb VOCs becomes exhausted, VOCs are again released to the atmosphere. A previous model of the GAC adsorption process used molar volume, VM, as an affinity coefficient to predict the breakthrough curves of the VOCs; however, an additional correction factor, δ, which had no theoretical base was necessary to adequately fit multicomponent breakthrough curves. In this paper, Hilderbrand's cohesive energy density term, c, is applied as the correction factor providing a more theoretical basis for multicomponent adsorption. When c is applied to the VM affinity coefficient, the heat of vaporization (Hv) adequately describes the multicomponent data and does not require additional correction factors to fit the breakthrough curves of a mixture of seven different chlorinated VOCs.
On‐line integrated control system for an industrial activated sludge process
Authors: Nam Sung Woo , Myung Nam Jin , Lee Kwang Soon
Published: October 2006

An on‐line integrated control system was devised for an activated sludge process. The process treats wastewater from a food processing plant where the disposal rate and composition of wastewater fluctuate drastically. The major objectives of the control system were to maintain the process effluent chemical oxygen demand (COD) below 50% of the regional regulation limit and to minimize the cost of aeration. The integrated control system consists of two layers, supervisory control and process control layers. In the process control layer, six independent control loops were configured for four kinds of process variables; influent flow rate, pH, DO, and mixed liquor suspended solids of the series of aeration tanks. In the supervisory control layer, a rule‐based expert system was used to provide optimum set points for the process control layer. In addition, a valve position control loop was designed to minimize the throttling loss through aeration valves and a rule‐based load distribution system was devised to prevent some of the blowers from being excessively worn out. The developed control system has been successfully operated for over 2 yr. After installation of the integrated control system, the average effluent COD was decreased by more than 50% compared with the COD before installation, and at the same time the cost of aeration was reduced by about 50%.
Alternating aerobic‐anoxic process for nitrogen removal: Dynamic modeling
Authors: Huang Jason , Hao Oliver J.
Published: October 2006

A dynamic mathematical model was developed for the alternating aerobic‐anoxic (AAA) completely mixed activated sludge process for the removal of carbonaceous substrate, nitrification, and denitrification. The model is constructed on the Activated Sludge Model No. 1 (ASM 1) of the International Association on Water Pollution Research Control with some revisions including pH and alkalinity. Experimental data obtained from a bench‐scale AAA reactor under different operational conditions were used for parameter estimation and model validation. Model parameters were found to agree well with those used by the ASM 1. Process performance at steady‐state and dynamic conditions can be well predicted by the AAA model. Because nitrite is not treated as a state variable in the ASM 1, a modified model incorporating nitrite as a state variable has been developed to account for nitrite accumulation.
Evaluation of estimation methods for organic carbon normalized sorption coefficients
Authors: Baker James R.
Published: October 2006

A critically evaluated set of 94 soil water partition coefficients normalized to soil organic carbon content (Koc) is presented for 11 classes of organic chemicals. This data set is used to develop and evaluate (Koc) estimation methods using three different descriptors. The three types of descriptors used in predicting (Koc) were octanol/water partition coefficient (Kow), molecular connectivity (mχ1), and linear solvation energy relationships (LSERs). The best results were obtained estimating Koc from Kow, though a slight improvement in the correlation coefficient was obtained by using a two‐parameter regression with Kow and the third order difference term from mχ1. Molecular connectivity correlations seemed to be best suited for use with specific chemical classes. The LSER provided a better fit than mχ1, but not as good as the correlation with Kow. The correlation to predict Koc from Kow was developed for 72 chemicals; log Koc = 0.903* log Kow + 0.094. This correlation accounts for 91% of the variability in the data for chemicals with log Kow ranging from 1.7 to 7.0. The expression to determine the 95% confidence interval on the estimated Koc is provided along with an example for two chemicals of different hydrophobicity showing the confidence interval of the retardation factor determined from the estimated Koc. The data showed that Koc is not likely to be applicable for chemicals with log Kow < 1.7. Finally, the Koc correlation developed using Kow as a descriptor was compared with three nonclass‐specific correlations and two “commonly used” class‐specific correlations to determine which methode(s) are most suitable.
A Benders decomposition model for sewer rehabilitation planning for infiltration and inflow planning
Authors: de Monsabert Sharon , Thornton Paul
Published: October 2006

Infiltration and inflow (I/1) to a wastewater treatment plant can contribute significantly to the quantity and cost of domestic wastewater treatment. A known pipe or manhole defect can be repaired in a number of ways. Leaking pipes, for example, can be chemically grouted, lined, or burst/lined or excavated and repaired/replaced. Each repair option for eliminating the infiltration or inflow has a unique cost and efficiency. A general Benders decomposition model was developed to optimize the repair and replacement strategy for a sewer network. The model determines the least cost solution by minimizing the combined wastewater treatment and repair costs. The results of a detailed analysis of an existing sewer are presented.
A theoretical model for blinding in cake filtration
Authors: Sørensen Birgitte L. , Keiding Kristian , Lauritzen Steffen L.
Published: October 2006

This study concerns blinding of the filter cake during filtration of wastewater solids. A theoretical model is suggested that describes blinding as happening in the filter cake only and not in the filter medium. It is based on the idea of having a filter cake built up by larger particles. This filter cake then serves as a secondary filter for small‐scale solids. Data obtained from filtering wastewater solids show good agreement between the estimated parameters for the amount of small‐scale solids and the degree of blinding. This indicates that the model is plausible.
Detritiation of water using microporous hollow‐fiber membranes
Authors: Kelso Robert C. , Ahmed Tariq , Middlebrooks E. Joe
Published: October 2006

A novel concept of tritium (HTO) removal with microporous hollow fiber membranes was evaluated in this study. Small‐scale laboratory modules were constructed and tested to determine the mass transfer characteristics of the hollow fibers under varying system parameters. Tritiated water is pumped through the fiber lumen and air, saturated with water vapor, is pumped over the exterior of the fibers in a countercurrent mode. The high HTO concentration gradient encourages the HTO to diffuse across the porous membrane wall, and to transfer directly into the saturated air stream. A dimensionless mathematical correlation that predicts the tritium transfer coefficient across the membranes is presented for parallel flow modules. The measured overall mass transfer coefficients in the membrane module are two to three orders of magnitude greater than those of conventional bubble stripping. In addition, factors that influence the mass transfer performance of the membrane modules in practical applications are evaluated. The results indicate that very low concentrations of HTO can be separated from water using microporous hollow fiber membranes.
The role of field trials in development and feasibility assessment of surfactant‐enhanced aquifer remediation
Authors: Fountain John C.
Published: October 2006

The development of surfactants for aquifer remediation involved simultaneous research at laboratory and field scale to expedite technology development. The results of field trials provided direction for laboratory research by identifying the critical parameters that limit performance while the results of laboratory research helped design and interpret the field trials. The combined field and laboratory work has identified the factors to be considered in a feasibility assessment of surfactant‐enhanced remediation. The principal requirements are adequate hydraulic conductivity (> 10−6 m/s), the ability to attain hydraulic control and ability to control downward dissolved nonaqueous phase liquid migration. Field trials have demonstrated that surfactants can rapidly remove mass; however, because heterogeneities cause tailing in contamination removal, restoration to drinking water standards may not be achieved. Optimization of surfactant solution composition can increase the rate of mass removal and hence minimize cost. The fraction of mass removal, the level of contamination remaining and the cost of remediation using surfactants are all dependent upon a site's hydrogeology. Thus both minimization of cost and maximization of nonaqueous phase liquid removal requires detailed site characterization as well as optimization of surfactant solution composition. Field trials provide an essential component both in technology development and detailed feasibility studies.
Increasing implementation of in situ treatment technologies through field‐scale performance assessments
Authors: Gierke John S. , Powers Susan E.
Published: October 2006

In situ treatment technologies are important components of subsurface remediation efforts at a wide variety of sites. Too often, however, innovative technologies are not given adequate consideration by consultants, regulators, and site owners due to a lack of conclusive evidence that they will be effective alternatives. Field‐scale demonstrations of the efficacy of in situ remediation technologies are important for effective engineering design. These types of projects provide an increase in the accuracy of conceptual models of the governing processes and can elucidate the practical aspects of full‐scale implementation. Demonstration projects conducted at the field scale have a number of components necessary for complete assessment of treatment performance. Depending somewhat on the technology, these can include: pre‐ and posttreatment sampling, detailed site characterization of stratigraphy and hydrogeology, and comparisons between predictions of engineering models and actual performance.
Dewatering and settling of activated sludges: The case for using cation analysis
Authors: Higgins Matthew J. , Novak John T.
Published: October 2006

Seven mixed liquor samples from full‐scale activated sludge systems were analyzed for their settling and dewatering properties, and the calcium, magnesium, sodium, and potassium concentrations were measured. The soluble cation concentrations were evaluated in terms of the monovalent to divalent cation ratio and the calcium to magnesium ratio. The monovalent to divalent ratio was positively correlated to activated sludge dewatering properties. In batch tests, the addition of calcium or magnesium to samples with a high monovalent to divalent cation ratio improved the dewatering rate of the suspensions by ≤30%. Conditioning and dewatering experiments were performed on thickened sludges from two of the industrial samples. Calcium was added to each sample, in one case, to lower the monovalent to divalent cation ratio and in the second case, to increase the calcium to magnesium ratio. In each case, addition of calcium to the sample reduced the optimum polymer dose for conditioning by 30% compared with control samples with no added calcium. Laboratory reactor studies were performed using mixed liquor and wastewater from three of the activated sludge plants. Two of the systems were deficient in magnesium, and one system was deficient in calcium. In each case, the deficient cation was added to the feed of the reactors, and settling and/or dewatering properties improved. Addition of cations to the feed of two full‐scale activated sludge systems improved the settling dramatically, and in one system, the thickened solids content was doubled. These results indicate that cation imbalances are a common cause of sludge settling and dewatering problems in industrial activated sludge plants, and these imbalances can be corrected by addition of the cation deemed to be deficient by analysis of the monovalent to divalent ratio or the calcium to magnesium ratio.
Survival and recovery of seeded HIV in water and wastewater
Authors: Casson Leonard W. , Ritter Michael O.D. , Cossentino Lisa M. , Gupta Phalguni
Published: October 2006

Acquired Immunodeficiency Syndrome (AIDS) is one of the major public health concerns in the world today. The Human Immunodeficiency Virus (HIV), the causative agent of AIDS, has been isolated from blood, semen, and other body fluids as well as excretions from infected individuals as both free virions, cell‐free virus, and as productively infected cells, cell‐associated virus. These body fluids and excretions, when discharged into wastewater collection systems, may contribute to the presence of HIV in wastewater. This raw wastewater, which may contain HIV, passes through wastewater treatment systems and may pose a potential health threat to wastewater treatment plant workers. The objectives of this research were to develop a better understanding of the survival of cell‐associated HIV in wastewater and to develop reliable methods for the concentration and recovery of HIV from wastewater. Casson et al. (1992) reported survival of cell‐free HIV in primary and secondary effluent ≤12 h followed by a reduction in titer 1‐ to 2‐ log in 24–48 hr. The infectivity of cell‐associated HIV was observed to be reduced rapidly after exposure to distilled water. However, a subpopulation of cell‐associated HIV was observed to remain stable through 48 h and remain infectious for ≤96 h in distilled water. Preliminary results indicate that cell‐associated HIV infectivity in nonchlorinated secondary effluent was less stable than in distilled water. Using a bentonite adsorption‐elution procedure, the authors have been able to recover HIV from distilled water and primary and secondary effluent at an efficiency of 30–50% to achieve an 8‐ to 10‐fold concentration depending on the initial HIV concentration. The bentonite‐adsorption elution procedure combined with RT‐PCR amplification provided a highly sensitive procedure for the detection of HIV in water and wastewater as low as one HIV particle per 25 m1.
Review of analytical methods for the determination of chlorine dioxide
Authors: Tzanavaras Paraskevas , Themelis Demetrius , Kika Fotini
Published: October 2006

The present study reviews more than twenty years (1985-present) of published research on the development and application of analytical procedures for the determination of chlorine dioxide, a widely used disinfectant and bleaching agent. The review covers a variety of techniques including batch and automated spectrophotometry and fluorimetry, electroanalysis and chromatography. The analytical figures of merit to the methods are presented, while critical discussion regarding their advantages and disadvantages is addressed.
An investigation of skeletal indicators of vitamin D deficiency in adults: Effective markers for interpreting past living conditions and pollution levels in 18th and 19th century Birmingham, England
Authors: Brickley Megan , Mays Simon , Ives Rachel
Published: October 2006

Vitamin D deficiency in adults is referred to as osteomalacia, and this condition has multiple causes related to factors such as environment, living conditions and cultural practices. Therefore, understanding the types and range of expression of osteomalacia in archaeological bone, using a number of investigative techniques, will have significant implications for interpretations made about past communities. This study aimed to understand the expression of vitamin D deficiency in the skeletons of adults through detailed analysis of human bone from the late 18th and 19th century churchyard of St. Martin's, Birmingham, England, at a gross, radiological and histological level. The collection from St. Martin's is unusual for the period as this central burial ground in Birmingham was used by a wide cross section of society rather than a narrow socio‐economic group as at other sites of this date. Macroscopic and radiological analysis of 291 adults identified seven individuals with osteomalacia, and histological analysis using back‐scattered scanning electron microscopy confirmed the findings. Detailed description of the range of pathological alterations observed in the archaeological skeletons are presented, and possible interpretations of the patterns seen considered. The results of this investigation will enable clear diagnosis and interpretation of this vitamin D deficiency disease, an important socio‐economic indicator, to take place in the future. Am J Phys Anthropol, 2006. © 2006 Wiley‐Liss, Inc.
A Substrate‐Based Folding Process Incorporating Chemodifferentiating ABB′ Three‐Component Reactions of Terminal Alkynoates and 1,2‐Dicarbonyl Compounds: A Skeletal‐Diversity‐Oriented Synthetic Manifold
Authors: Tejedor David , Sántos‐Expósito Alicia , García‐Tellado Fernando
Published: October 2006

A novel three‐component reaction (3CR)‐based folding process that is able to generate complexity and skeletal diversity is described. The process utilizes chemodifferentiating organocatalyzed ABB′ 3CRs of a terminal conjugated alkynoate (building block) with α‐dicarbonyl compounds (diversity‐generating blocks) to generate an array of different molecular topologies (γ‐lactones, linear propargylic enol ethers, or 1,3‐dioxolane rings). Amides and esters behave as efficient reactivity‐encoding elements (σ) of the attached keto functionality. Three chemical properties govern the chemical outcome of this folding process: acidity, nucleophilicity (of the catalyst), and carbonyl electrophilicity. Overall, this substrate‐based folding process generates three different molecular architectures from the same modular functionalities (ketones) and under the same reaction conditions (methyl propiolate and tertiary amine). In addition, and very importantly for combinatorial applications, all of the products share a common reactive functionality that allows them to be collective substrates for a subsequent diversity‐generating process.
A Novel Strategy for the Design of 8‐Hydroxyquinolinate‐Based Lanthanide Bioprobes That Emit in the Near Infrared Range
Authors: Comby Steve , Imbert Daniel , Vandevyver Caroline , Bünzli Jean‐Claude G.
Published: October 2006

A new polydentate tripodal ligand T2soxMe was synthesized to take advantage of the chelating effect of tridentate 8‐hydroxyquinolinate subunits. Potentiometric and spectrophotometric titrations reveal seven pKa values of between 3.7 and 10.2. In water, the use of T2soxMe leads to thermodynamically stable and soluble LnIII complexes at physiological pH, with conditional stability constants in the range log β11=7.8–8.6. The chelates are resistant toward hydrolysis and show interesting photophysical properties, particularly in the near infrared (NIR) range. The emission lifetimes of the NdIII and YbIII complexes recorded in D2O and H2O suggest the absence of water molecules in the first coordination sphere of the metal ions. Moreover, the low energy of the triplet state allows efficient energy transfer from the ligand to the metal ions: in water at pH 7.4, the sensitization efficacy of the NIR luminescence reaches 75 and ≈100 % for NdIII and YbIII, respectively, leading to overall quantum yields of 0.027 and 0.13 %; ErIII luminescence is also detected. According to the WST‐1 test, the YbIII podate at concentrations of up to 250 μM does not display sizeable cytotoxicity for Jurkat cells after 24 h of incubation. Finally, the same podate is shown to couple to human serum albumin, leading to an increase of 50 % in the NIR‐luminescence intensity.
Which nido:nido‐Macropolyhedral Boranes Are Most Stable?
Authors: Kiani Farooq Ahmad , Hofmann Matthias , et al. et al.
Published: October 2006

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.
Pb122‐: Plumbaspherene.
Authors: Cui Li‐Feng , Huang Xin , Wang Lei‐Ming , Li Jun , Wang Lai‐Sheng
Published: October 2006

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.
Rhenium Tellurobromide Re6Te16Br6.
Authors: Mironov Yuri V. , Kim Sung‐Jin , Fedorov Vladimir E.
Published: October 2006

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.
Anisotropic Transport and Magnetic Properties of Ternary Uranium Antimonides U3ScSb5 and U3TiSb5.
Authors: Mar Arthur , Tougait Olivier , Potel Michel , Noel Henri , Lopes Elsa B.
Published: October 2006

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 Isothermal Section of the Gd—Dy—Co Ternary System at 800 K.
Authors: Zhuang Y. H. , Zhu Q. M. , Li J. Q. , Zhou K. W. , Deng J. Q. , He W.
Published: October 2006

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.
Dimers of Heptapnictide Anions: As144‐ and P144‐ in the Crystal Structures of [Rb(18‐Crown‐6)]4As14×6NH3 and [Li(NH3)4] 4P14×NH3.
Authors: Hanauer Tobias , Aschenbrenner Juergen C. , Korber Nikolaus
Published: October 2006

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.
Amine‐Intercalated Layered SnII Phosphates with Open‐Framework Structures.
Authors: Ramaswamy Padmini , Natarajan Srinivasan
Published: October 2006

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.
Anodic Fluorination of β,β‐Bis(methylthio)vinyl Phenyl Ketone.
Authors: Cao Yi , Tajima Toshiki , Fuchigami Toshio
Published: October 2006

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.
An Efficient and Highly Stereoselective Synthesis of New P‐Chiral 1,5‐Diphosphanylferrocene Ligands and Their Use in Enantioselective Hydrogenation.
Authors: Chen Weiping , Roberts Stanley M. , Whittall John , Steiner Alexander
Published: October 2006

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.
TEMPO‐Linked Metalloporphyrins as Efficient Catalysts for Selective Oxidation of Alcohols and Sulfides.
Authors: Huang Jian‐Ying , Li Shi‐Jun , Wang Yan‐Guang
Published: October 2006

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 of (Fluoroalkyl)amines by Deoxyfluorination of Amino Alcohols.
Authors: Nomoto Takashi , Fukuhara Tsuyoshi , Hara Shoji
Published: October 2006

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.
Highly Enantioselective Cyanation of Aldehydes Catalyzed by a Multicomponent Titanium Complex.
Authors: Gou Shaohua , Chen Xiaohong , Xiong Yan , Feng Xiaoming
Published: October 2006

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.
Solid Silica Sulfuric Acid (SSA) as a Novel and Efficient Catalyst for Acetylation of Aldehydes and Sugars.
Authors: Wu Hui , Shen Yang , Fan Li‐yan , Wan Yu , Shi Da‐qing
Published: October 2006

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.
Metal‐Catalyzed Bond Reorganization of 1,3‐Diynes.
Authors: Cho Eun Jin , Kim Mansuk , Lee Daesung
Published: October 2006

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.
SiO2‐TBD as New Heterogeneous Catalyst for the Nef Conversion of Secondary Niroalkanes under Neat Conditions.
Authors: Ballini Roberto , Fiorini Dennis , Maggi Raimondo , Oro Chiara , Palmieri Alessandro , Sartori Giovanni
Published: October 2006

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.
Rhodium‐Catalyzed Intermolecular Chelation Controlled Alkene and Alkyne Hydroacylation: Synthetic Scope of β‐S‐Substituted Aldehyde Substrates.
Authors: Willis Michael C. , Randell‐Sly Helen E. , Woodward Robert L. , McNally Steven J. , Currie Gordon S.
Published: October 2006

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.
Novel Tandem Reactions of Ethyl Acetoacetate with Aromatic Aldehydes: Product‐ and Stereoselective Formation of Highly Functionalized Cyclohexanones.
Authors: Srinivasan Murugesan , Perumal Subbu
Published: October 2006

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.
Beneficial Effect of TMSCl in the Lewis Acid‐Mediated Carboxylation of Aromatic Compounds with Carbon Dioxide.
Authors: Nemoto Koji , Yoshida Hiroki , Suzuki Yutaka , Morohashi Naoya , Hattori Tetsutaro
Published: October 2006

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.
One‐Pot Wittig Reactions in Water and in the Presence of a Surfactant.
Authors: Orsini Fulvia , Sello Guido , Fumagalli Tiziano
Published: October 2006

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.
Substituent‐Induced Regioselective Synthesis of 1,2‐Teraryls and Pyrano[3,4‐c]pyran‐4,5‐diones from 2H‐Pyran‐2‐ones.
Authors: Pratap Ramendra , Kumar Brijesh , Ram Vishnu Ji
Published: October 2006

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.
Diversity‐Oriented Synthesis of 2,5‐Disubstituted Tetrahydrofurans Based on a “Cyclization‐Hydrogenation‐Substitution” Strategy.
Authors: Freifeld Ilia , Holtz Edith , Dahmann Georg , Langer Peter
Published: October 2006

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 of Pyrrolidines via Palladium(II)‐Catalyzed Aerobic Oxidative Carboamination of Butyl Vinyl Ether and Styrenes with Allyl Tosylamides.
Authors: Scarborough Christopher C. , Stahl Shannon S.
Published: October 2006

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 of 2‐Aroylmethylidene‐6‐hydroxy‐2,3‐dihydroindol‐3‐ones.
Authors: Gein V. L. , Demeneva A. V. , Rassudikhina N. A. , Vakhrin M. I.
Published: October 2006

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.
3‐Bromopropenyl Methylcarbonate Organic Synthesis: A Straightforward Approach to 4,5‐Disubstituted 5‐Vinyl‐1,3‐dioxolan‐2‐ones.
Authors: Lombardo Marco , Pasi Filippo , Trombini Claudio
Published: October 2006

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.