bluuebunny/crossref_metadata_2025 huggingface dataset:
Herbicides
Authors: Plimmer Jack R. , Bradow Judith M. , Dionigi Christopher P. , Johnson Richard M. , Wojkowski Suhad
Published: September 2004

Weeds, ie, unwanted plants, reduce crop yields and quality. Of the many approaches used to control weeds, the use of chemical herbicides is considered the most effective and efficient. Herbicides are a critical factor in agricultural productivity and represent a significant economic input in crop production. This review discusses herbicide mode of action, environmental fate, and chemistry, as well as the historical perspectives and future trends in herbicide development. Topics addressed include analytical methods, allelopathy and natural products, biological control, carcinogenicity, herbicide degradation, leaching, sorption, volatilization, movement in soil, enzyme and biosynthesis inhibition, free‐radical induction, photosynthesis and pigment bleaching, plant growth regulators, seed safeners, water quality, and weed seeds. Primary herbicide groups include acid amides, amino acid analogues, aliphatic carboxylic acids, benzonitriles, bipyridiniums, carbamates, dinitroanilines, diphenyl ethers, imidazoles, inorganic and metallorganic compounds, mycoherbicides, phenoxy acids, phenoxyalkanoic acids, pyridines, pyridazones, phthalics, sulfonylureas, thiocarbamates, triazines, and ureas. Miscellaneous herbicides include acrolein, cinmethylin, clethodim, clomazone, ethofumesate, sethoxydim, and tridiphane. A list of herbicide, agrichemical, and toxicology databases is provided.
Latex Technology
Authors: Grady Michael C.
Published: September 2004

Latices are colloidal dispersions of discrete polymer particles, usually in an aqueous medium. Technology used to make and use latex involves many aspects of colloidal and polymer chemistry. This article reviews the fundamentals of emulsion polymerization, the techniques used to make most synthetic latices, general properties of latices, as well as colloidal and polymer compounding ingredients to convert latices into useful products, and discusses the wide variety of applications in which latices are used.
The effects of training professional groups and lay persons to use criteria‐based content analysis to detect deception
Authors: Akehurst Lucy , Bull Ray , Vrij Aldert , Köhnken Günter
Published: September 2004

This experiment was designed to assess, for the first time, the effects of training police officers, social workers and students in Criteria‐Based Content Analysis (CBCA) in an attempt to increase lie detection accuracy. A within‐subjects design was implemented. Participants rated the truthfulness of a maximum of four statements before training in CBCA and rated the truthfulness of a different set of four statements after training. The raters were only exposed to the written transcripts of the communicators. Two thirds of the statements utilized were truthful and one third were based on fabrications. Before training, there were no significant differences in detection accuracy between the police officers (66% accuracy), the social workers (72% accuracy) and the students (56% accuracy). After training, the social workers were 77% accurate and significantly more accurate than the police officers (55%) and the students (61%). However, none of the three groups of raters significantly improved their lie detection accuracy after training, in fact, the police officers performed significantly poorer. Overall, police officers were significantly more confident than social workers and lay persons regardless of accuracy. Further, participants were most confident when labelling a statement truthful regardless of whether or not this was the correct decision. Copyright © 2004 John Wiley & Sons, Ltd.
Inter‐laboratory analysis of endotoxin in cotton dust samples
Authors: Jacobs Robert R. , Chun David
Published: September 2004

Background

Currently there are no mandated exposure limits for endotoxin, but recommended limits have been proposed and interest expressed in developing quantitative standards for endotoxin. A limitation for developing a quantitative standard for endotoxin is the measurement variability between laboratories. Inter‐laboratory variability of up to four orders of magnitude has been reported for replicate samples. To evaluate both the intra‐ and inter‐laboratory variability, Round–Robin studies were conducted using replicate samples of cotton dust.

Methods

Replicate samples of cotton dust were collected using vertical elutriators (VE) in a model cardroom. Each participating laboratory evaluated the samples for endotoxin using: their normal extraction procedure; a common extraction procedure; and a common extraction procedure and the same type and lot of a commercially available endotoxin kit.

Results

These studies demonstrated that both intra‐ and inter‐laboratory variability is reduced by using a common extraction protocol and a common assay kit; however, significant differences remained between the laboratories.

Conclusions

The data suggest that intra‐laboratory assays can be used to assess the relative differences between endotoxin samples, however, the inter‐laboratory variability suggests that limitations remain for developing a reliable exposure assessment assay that could be used for a quantitative exposure standard. Am. J. Ind. Med. 46:333–337, 2004. © 2004 Wiley‐Liss, Inc.
Differences in cellular and inflammatory cytokine profiles in the bronchoalveolar lavage fluid in bagassosis and silicosis
Authors: Zhai Rihong , Ge Xianmin , Li Helin , Tang Zhongquan , Liao Ruiqing , Kleinjans Jos
Published: September 2004

Background

Little is known about the crucial mediators involved in the inflammation and fibrogenesis in bagassosis. The aim of this study was to characterize the cellular and cytokine patterns in the airways of bagassosis and to compare these with silicosis subjects and controls.

Methods

Bronchoalveolar lavage (BAL) was performed in 11 patients with bagassosis, 16 cases with silicosis, and 8 controls. Differential cell counts, total protein concentration, TNF‐α, IL‐1β, IL‐5, IL‐6, and IL‐8 were analyzed in the bronchoalveolar lavage fluid (BALF).

Results

Bagassosis was characterized with hypercellularity with neutrophilia in BALF; while the predominant cell in the BALF in silicosis was macrophage. Compared with control subjects, increased TNF‐α, IL‐1β, IL‐8, and IL‐6 levels were found in the BALFs in both bagassosis and silicosis. Furthermore, IL‐6 levels in the BALF of silicosis subjects were significantly higher than that seen in bagassosis. In contrast, bagassosis had higher level of IL‐8 in BALF than that in silicosis. Relationship among these parameters were found between IL‐8 levels and neutrophils, lymphocytes and IL‐1 β in bagassosis, macrophages and IL‐1β in silicosis. No significant differences of total protein concentrations and IL‐5 in BALF were found between controls or bagassosis, and silicosis.

Conclusions

The findings of this study suggest that neutrophils, TNF‐α, IL‐1β, IL‐8, and IL‐6 are involved in the pathogenesis in bagassosis. The mechanisms underline the different cellular and cytokine profiles in bagassosis and silicosis warrant further investigation. Am. J. Ind. Med. 46:338–344, 2004. © 2004 Wiley‐Liss, Inc.
Acute toxic pneumonitis complicating chronic obstructive pulmonary disease (COPD) in a farmer
Authors: Sigurdarson Sigurdur T. , Donham Kelley J. , Kline Joel N.
Published: September 2004

Background

Toxic pneumonitis or Organic Dust Toxic Syndrome (ODTS) is a common, usually self‐limiting condition among agricultural workers, occurring after high level exposure to agricultural dust.

Case Report

We describe the case of a 68‐year‐old smoker and farmer who became ill with dyspnea, flu‐like symptoms, and hypoxia after cleaning out a grain bin.

Results

Chest radiograph was normal. He was treated with steroids, antibiotics, and oxygen supplementation and recovered over 3 months, but continues with lingering exercise intolerance after 2 years.

Discussion

Although toxic pneumonitis usually follows a relatively benign course with spontaneous recovery and no permanent sequale it can lead to the exacerbation of underlying lung conditions, resulting in incomplete or delayed recovery. Prevention is aimed at limiting exposure by avoidance, by increasing ventilation in closed spaces and by appropriate use of personal protective equipment. Am. J. Ind. Med. 46:393–395, 2004. © 2004 Wiley‐Liss, Inc.
Solubility of endotoxins from Escherichia coli and Pseudomonas aeruginosa
Authors: Eduard Wijnand , Westby Mette Haraldsen , Larsson Lennart
Published: September 2004

Background

The Limulus amebocyte lysate (LAL) assay may underestimate endotoxins because only soluble endotoxins are determined. The solubility of endotoxins was, therefore, studied in two species of Gram‐negative bacteria.

Methods

Cultures were grown in serum broth, cells were harvested by centrifugation and washed in physiological saline. Bacterial suspensions were either filtered through PTFE filters and air dried at room temperature, dried in polypropylene tubes at room temperature in a desiccator, or freeze dried. Samples were extracted with aqueous Tween 20. The soluble and insoluble fractions were dried, methanolysed, and hydroxy‐fatty acid methyl esters were determined by gas chromatography (GC) as markers of endotoxins.

Results

The solubility of the endotoxins from Escherichia coli and Pseudomonas aeruginosa ranged from 9% to 83%. Species and drying conditions had substantial influence on the solubility.

Conclusions

Endotoxin exposure may be underestimated in environmental samples by the LAL test because a substantial fraction can be non‐soluble and is not detected. Am. J. Ind. Med. 46:375–377, 2004. © 2004 Wiley‐Liss, Inc.
Multimetallic Cooperative Activation of N2
Authors: Gambarotta Sandro , Scott Jennifer
Published: September 2004

The impressive number of breakthroughs reported in recent years in the field of dinitrogen activation reiterates the great interest that is still attracted by this molecule as a target for molecular activation studies. In spite of the fact that the discovery of dinitrogen fixation is rapidly approaching its 40th birthday, a thorough understanding of the factors that determine either fixation or activation is yet to be achieved. Nevertheless, substantial progress has recently been made. The aim of this article is to review some of the most recent literature and to assess the necessity of multimetallic attack to dinitrogen as a prerequisite towards further cleavage and functionalization.
Long‐term exposure of several marine benthic animals to static magnetic fields
Authors: Bochert R. , Zettler M.L.
Published: September 2004

Electrical currents in underwater sea cables could induce magnetic fields. The sea cables lie on or within the sea bottom and this is the living area for many invertebrate and vertebrate species. North Sea prawn Crangon crangon (Crustacea, Decapoda), round crab Rhithropanopeus harrisii (Crustacea, Brachyura), glacial relict isopod Saduria entomon (Crustacea, Isopoda), blue mussel Mytilus edulis (Bivalvia), and young flounder Plathichthys flesus (Pisces) were exposed to a static magnetic field (MF) of 3.7 mT for several weeks. The results showed no differences in survival between experimental and control animals. Mussels M. edulis were kept under static magnetic field conditions for 3 months during their reproductive period in spring. The determination of gonad index and condition index revealed no significant differences to the control group. Bioelectromagnetics 25:498–502, 2004. © 2004 Wiley‐Liss, Inc.
Effects of combined DC and AC magnetic fields on germination of hornwort seeds
Authors: Kobayashi Masanori , Soda Naoya , Miyo Takuya , Ueda Yoshiro
Published: September 2004

Seeds of hornwort (Cryptotaenia japonica Hassk) were exposed to sinusoidally time‐varying extremely low frequency (ELF) magnetic fields (AC fields) in combination with the local geomagnetic field (DC field). Exposure lasted 24 h/day for 16 days. Three directions of the AC magnetic fields were considered; the vertical (magnetic flux density $\vec B_{ACV}$), the directions parallel ($\vec B_{AC||}$), and perpendicular ($\vec B_{AC \bot }$) to the direction of total geomagnetic field (magnetic flux density $\vec B_G$) in the geomagnetic plane (GP). Controls consisted of seeds exposed to zero AC magnetic fields in combination with the DC magnetic field. The $\vec B_{ACV}$ in combination with $\vec B_G$ effectively promoted the germination of hornwort seeds when applied at 750 μT (RMS) at 7 Hz or 500 μT (RMS) at 14 Hz from among the cases of individual frequencies f = 3.5, 7.0, 10.5, 14.0 Hz at 500 and 750 μT. The $\vec B_{AC||}$ promoted the germination of hornwort seeds more effectively than the $\vec B_{AC \bot }$ in combination with $\vec B_G$ when 500 and 750 μT at 7 Hz were applied. Bioelectromagnetics 25:552–559, 2004. © 2004 Wiley‐Liss, Inc.
Guidance for exposure design of human studies addressing health risk evaluations of mobile phones
Authors: Kuster Niels , Schuderer Jürgen , Christ Andreas , Futter Peter , Ebert Sven
Published: September 2004

Conflicting results have recently emerged from human provocation studies that addressed the possible health hazards of radio frequency (RF) field exposure from mobile phones. Different findings may have resulted from exposures that are poorly defined and difficult to compare. The aim of this study was to develop guidelines to facilitate the development of exposure systems for human volunteer studies which lead to reproducible results and which provide maximum relevance with respect to the assessment of the safety of mobile technology. The most important exposure parameters are discussed such as the signal, field distribution, and field strength, as well as the minimum requirements for the setup and dosimetry. Bioelectromagnetics 25:524–529, 2004. © 2004 Wiley‐Liss, Inc.
Arteriovenous glomeruli of the human spinal cord and their possible functional implications
Authors: Parke Wesley W.
Published: September 2004

A previous investigation of the radiculomedullary vascular distribution of the human spinal cord showed an immediate filling of the peripheral spinal veins during arterial injections. Because the perfused medium, a mixture of latex and India ink, had a sufficient viscosity to preclude capillary passage, an extensive system of arteriovenous anastomoses (AVA) was indicated. The injection of five additional anatomic cadaver spinal cords was undertaken to specifically determine the intraparenchymal position and structure of these AVA. It was found that only cleared and transilluminated longitudinal parasagittal sections adequately showed that the AVA were formed by an extensive array of intricately coiled arteriovenous glomeruli (AVG) that could pass substantial amounts of blood from third order arterial branches to equivalently sized veins, bypassing the capillary bed. The epithelioid structure of these AVG channel walls, coupled with their highly innervated adventitial tissue indicated a possible functional relationship to similar structures found in the ends (digital pads) of mammalian extremities. Stained serial sections of injected cords showed the vascular relations with nerve fibers derived from the intraspinal parenchyma as well as a possible extraparenchymal autonomic fiber source. The numbers and extent of these AVG complexes suggested they might be involved in the remarkable autoregulation of spinal cord blood flow (SCBF) that is impervious to middle range changes in systemic blood pressure. Future research may more accurately determine the functional role of these previously unreported human spinal AVG, particularly in their possible relation to SCBF autoregulation in normal and injured spines. Clin. Anat. 17:558–563, 2004. © 2004 Wiley‐Liss, Inc.
Regioselective Samarium Diiodide Induced Couplings of Carbonyl Compounds with 1,3‐Diphenylallene and Alkoxyallenes: A New Route to 4‐Hydroxy‐1‐enol Ethers
Authors: Hölemann Alexandra , Reißig Hans‐Ulrich
Published: September 2004

Since its introduction into synthetic organic chemistry, samarium diiodide has found broad application in a variety of synthetically important transformations. Herein, we describe the first successful intermolecular additions of samarium ketyls to typical allenes such as 1,3‐diphenylallene (7), methoxyallene (12) and benzyloxyallene (25). Reaction of different samarium ketyls with 1,3‐diphenylallene (7) occurred exclusively at the central carbon atom of the allene to afford products 9 in moderate to good yields. In contrast, reductive coupling of cyclic ketones to methoxyallene (12) regioselectively provided 4‐hydroxy‐1‐enol ethers 13, which derive from addition to the terminal allene carbon atom of 12, in moderate to good yields. Whereas the E/Z selectivity with respect to the enol ether double bond is low, excellent diastereoselectivity has been observed in certain cases with regard to the ring configuration (e.g. compound 13 b). Studies with deuterated tetrahydrofuran and alcohol were performed to gain information about the reaction mechanism of this coupling process, which involves alkenyl radicals. The couplings of samarium ketyls derived from acyclic ketones and aldehydes gave lower yields, and in several cases cyclopentanols 20 are formed as byproducts. Branched acyclic ketones and conformationally more flexible cyclic ketones such as cycloheptanone led to a relatively high amount of cyclopentanol derivatives 20, whose formation involves an intramolecular hydrogen atom transfer through a geometrically favoured six‐membered transition state followed by a cyclization step. The samarium diiodide mediated addition of 8 b to benzyloxyallene (25) afforded the expected enol ethers 26, albeit in only low yield. Additionally, spirocyclic compounds 27 and 28 were obtained, which are formed by a cascade reaction involving an addition/cyclization sequence. In the novel coupling process described here methoxyallene (12) serves as an equivalent of acrolein. The 1,4‐dioxygenated products obtained contain a masked aldehyde functionality and are therefore valuable building blocks in organic synthesis.
Xenopus paraxis homologue shows novel domains of expression
Authors: Carpio Ronald , Honoré Stella Maris , Araya Claudio , Mayor Roberto
Published: September 2004

The paraxis gene encodes a basic helix‐loop‐helix transcription factor that is expressed in paraxial mesoderm and whose mutant displays an inability to form epithelial somites. Here, the molecular characterization of Xenopus paraxis is reported. paraxis is expressed in the paraxial mesoderm and somites but is down‐regulated during muscle differentiation. In addition to its paraxial mesodermal expression, described in other organisms, two novel expression domains of paraxis were found: the neural tube and the head mesoderm. paraxis expression in the neural tube was compared with the expression of the neural markers Xash and Xiro1, and we concluded that paraxis is expressed in a broad band in the prospective sulcus limitans of the neural tube. Developmental Dynamics 231:609–613, 2004. © 2004 Wiley‐Liss, Inc.
Pacinian corpuscle development involves multiple Trk signaling pathways
Authors: Šedý J. , Szeder V. , Walro J.M. , Ren Z.G. , Naňka O. , Tessarollo L. , Sieber‐Blum M. , Grim M. , Kucera J.
Published: September 2004

The development of crural Pacinian corpuscles was explored in neonatal mutant mice lacking nerve growth factor (NGF), brain‐derived neurotrophic factor (BDNF), neurotrophin‐3 (NT3) or neurotrophin‐4 (NT4), or their cognate Trk receptors. Deficits of the corpuscles and their afferents were greatest in NT3, less in BDNF, and least in NT4 null mice. Deletion of NGF or p75NTR genes had little or no impact. No Pacinian corpuscles were present in NT3;BDNF and NT3;NT4 double or NT3;BDNF;NT4 triple null mice. Deficits were larger in NT3 than TrkC mutants and were comparable to deficits observed in TrkB or TrkA mutants. Afferents of all corpuscles coexpressed TrkA and TrkB receptors, and some afferents coexpressed all three Trk receptors. Our results suggest that multiple neurotrophins, in particular NT3, regulate the density of crural Pacinian corpuscles, most likely by regulating the survival of sensory neurons. In addition, NT3/TrkB and/or NT3/TrkA signaling plays a greater role than NT3/TrkC signaling in afferents to developing Pacinian corpuscles. Developmental Dynamics 231:551–563, 2004. © 2004 Wiley‐Liss, Inc.
Expression of mouse Foxi class genes in early craniofacial development
Authors: Ohyama Takahiro , Groves Andrew K.
Published: September 2004

Recent models of craniofacial development suggest the existence of a common pan‐placodal domain lying next to the neural plate, from which all sensory placodes will arise. In support of this idea, several genes are expressed in the surface ectoderm of the head adjacent to the neural plate, before the appearance of genes in specific cranial placodes. In this study, we examine the expression patterns of the mouse Foxi class genes from embryonic day 6.5 to 10.5. Foxi2 is expressed throughout the cranial ectoderm adjacent to the neural plate from the 4‐somite stage, later becoming excluded from the otic placode. Foxi3 is expressed in a broad region of the pan‐placodal ectoderm adjacent to the neural plate from embryonic day (E) 6.75 to the first somite stage. Its expression becomes restricted to the ectoderm and the endoderm of the branchial pouches at E10.5. Foxi1 expression is first detected in the endolymphatic duct in the otic vesicle at E10.5. These results suggest that the mouse Foxi class genes may play important roles, both during cranial placode specification and in later development of individual cranial sensory structures and other organs derived from the cranial ectoderm. Developmental Dynamics 231:640–646, 2004. © 2004 Wiley‐Liss, Inc.
Salmonella typhimurium infection halts development of type 1 diabetes in NOD mice
Authors: Zaccone Paola , Raine Tim , Sidobre Stéphane , Kronenberg Mitchell , Mastroeni Pietro , Cooke Anne
Published: September 2004

Infectious disease has been proposed as an environmental modifier of autoimmunity in both human populations and the NOD mouse. We found that infection of NOD mice with attenuated, but not killed, Salmonella typhimurium can reduce the incidence of type 1 diabetes (T1D), even if infection occurs after the development of a peri‐islet pancreatic infiltrate. Functional diabetogenic effector T cells are still present, as demonstrated by the initiation of diabetes in NOD‐scid recipients of transferred splenocytes. High levels of IFN‐γ are secreted by splenocytes of infected mice, but there is no evidence of involvement of IL‐10 in the protective effect of the infection. Finally, prolonged changes in cell subsets are observed in infected mice involving invariant Vα14Jα281 NKT and dendritic cells. These data reinforce the idea that prevention of T1D in the NOD mouse cannot be reduced to the simple Th1/Th2 paradigm and that different infections may involve different protective mechanisms.
A Homologous Series of Persubstituted Cyclodextrin Amino Acids: The Quest for Tubular Self‐Assembly
Authors: Kraus Tomáš , Buděšínský Miloš , Císařová Ivana , Závada Jiří
Published: September 2004

The synthesis, conformation and diverse self‐assembling patterns of the homologous series of chemically uniform per(6‐amino‐2‐O‐carboxymethyl‐6‐deoxy‐3‐O‐methyl)‐substituted α‐, β‐ and γ‐cyclodextrins 6a−6c are reported. Helical self‐assembly of the lowest homologue 6a gave rise to a three‐dimensional system of separate collinear channels. For the higher homologues 6b−6c, such a unique architecture is prohibited by unfavorable geometrical factors. A comparison has been made with the corresponding series of native and permethylated cyclodextrins, and the role played by hydrogen bonds in promoting tubular architectures has been assessed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synergetic Effects of Oxidative and Coordinative Promotors to Increase the Yield of a Twofold Pauson−Khand Reaction
Authors: Gleiter Rolf , Schulte J. Hilko , Werz Daniel B.
Published: September 2004

Four medium‐sized cyclic diynes (7, 15−17), two cyclic dithiadiynes (18, 19) and two cyclic tetrathiadiynes (20, 21) were starting materials for Pauson−Khand reactions with ethylene and (octacarbonyl)dicobalt under four different conditions: A with 1 equivalent n‐butylmethyl sulfide (BMS), B with 7.5 equivalents dimethyl sulfoxide (DMSO), C with 7.5 equivalents DMSO and 1 equivalent BMS and D with 7.5 equivalents DMSO and 7.5 equivalents BMS as additives. In the cases of 7 and 15−17, the yields increased strongly by applying protocol C. For 18−21, no increase in the yields was found under conditions A−D. These differences are discussed and ascribed to intramolecular S−Co interactions in the cases of 18−21. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
The Synthesis of the Dimethyl Ester of Quino[4,4a,5,6‐efg]‐Annulated 7‐Demethyl‐8‐deethylmesoporphyrin and Three of Its Isomers with Unprecedented peri‐Condensed Quinoline Porphyrin Structures. Molecules with Outstanding Properties as Sensitizers for Photodynamic Therapy in the Far‐Red Region of the Visible Spectrum
Authors: van der Haas Richard N. S. , de Jong Robertus L. P. , Noushazar Maryam , Erkelens Kees , Smijs Threes G. M. , Liu Yan , Gast Peter , Schuitmaker Hans J. , Lugtenburg Johan
Published: September 2004

The mesoporphyrin dimethyl ester nickel complex has been formylated via the Vilsmeier method. The four possible mono meso‐formyl derivatives were isolated and characterized. Wadsworth−Emmons coupling with the anion of (diethylphosphono)acetonitrile converted these aldehydes into the four novel meso acrylonitriles. Brief treatment of these acrylonitrile systems in hot trichloroacetic acid resulted in the formation of four achiral porphyrin derivatives with unprecedented nickel complexes of quino‐fused porphyrins. Subsequent removal of the nickel gave four quino‐porphyrin free bases: quino[4,4a,5,6‐efg]‐annulated 7‐demethyl‐8‐deethylmesoporphyrin dimethyl ester 6a, 2′‐(methoxycarbonyl)quino[4,4a,5,6‐jkl]‐annulated 12‐demethyl‐13‐de[2′‐(methoxycarbonyl)ethyl]mesoporphyrin dimethyl ester 6b, 2′‐(methoxycarbonyl)quino[4,4a,5,6‐qrs]‐annulated 18‐demethyl‐17‐de(2′‐methoxycarbonylethyl)mesoporphyrin dimethyl ester 6c and quino[4,5,6,7‐abt]‐annulated 2‐demethyl‐3‐deethylmesoporphyrin dimethyl ester 6d. The structures of these systems were unambiguously determined via mass spectroscopy and a plethora of NMR techniques. In the same way, etioporphyrin and octaethylporphyrin were converted into the corresponding peri‐condensed quinoporphyrins as products, which shows that the formation of novel pericondensed quino‐porphyrins is a general reaction in the porphyrin series and will have a wide scope in this field. Also, a plausible reaction mechanism for the formation of the quinoporphyrin systems was derived. As a first test for the use of these systems as sensitizers in far‐red phototherapy, the quantum yield of singlet oxygen generation by 6a in toluene was studied. This quantum yield is 0.77, which is even higher than the singlet oxygen generation by sensitized meso‐tetraphenylporphyrin. Secondly, when Chinese Hamster ovary (CHO) cells were incubated in medium which contained up to 15 μg/ml of 6a, the survival rate of the cells in the dark is complete within experimental error, showing that under these conditions, 6a is not toxic to CHO cells. When CHO cells incubated in medium containing 6a in concentrations of 1 μg/ml and higher were treated with white light of intensity 30 mW/cm2 for 15 minutes, complete cell death was observed. Based on these facts, we expect that all four achiral systems will show very promising properties to form the basis of a photodynamic therapy in far‐red light. The fact that these systems are achiral is an additional bonus for medical applications. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Enantioselective Synthesis and Circular Dichroism of Endocyclic Allenes
Authors: Zelder Claudia , Krause Norbert
Published: September 2004

The novel, enantiomerically enriched nine‐ and ten‐membered cyclic allenes (+)‐5a−c and (−)‐6a−c were synthesized by lipase‐catalyzed kinetic resolution of propargylic acetates 1/2 and subsequent anti‐stereoselective SN2′‐substitution with magnesium cuprates. The CD spectra of these allenes exhibit distinct features that are a function of the ring size and the alkyl substituent at the allene moiety. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Compared performances of different algorithms for estimating annual nutrient loads discharged by the eutrophic River Loire
Authors: Moatar Florentina , Meybeck Michel
Published: September 2004

Good estimates of pollutant fluxes are required for Earth systems sciences and water quality management. The gradual accumulation of water quality data records over the past few decades has increased the value of these data for examining long‐term trends. On many major rivers, however, infrequent sampling of most pollutants makes flux estimates and their analysis difficult. This paper explores the performance of different methods for estimating nutrient fluxes. The objective is to assess the accuracy (bias) and precision (dispersion) of annual nutrient fluxes based on monthly sampling, which is the frequency with which 80% of French water quality surveys have been carried out since 1971. The study is based on a data set of nutrient concentrations surveyed at high frequency during a 5 year pilot study (1981–85) at the Orléans station in the middle reaches of the River Loire, France. The mean specific fluxes were 641 (nitrate‐N), 96 (total‐P) and 37 kg year−1 km−2 (orthophosphate‐P). For each year, the data set was then ‘resampled’ by randomly simulating 12 sampling dates. 100 simulated monthly samplings were generated, upon which seven estimation methods were tested. The evaluations indicate that, when concentrations of specific substances in large rivers exhibit seasonal variation, a simple method based on linear interpolation between samples taken at approximately monthly intervals is advocated. With the monthly sampling interval, the precision (confidence level of 95%) of annual nutrient fluxes obtained by the appropriate methods was 13% for nitrates, 20% for total‐P, 26% for orthophosphates, and 34% for particulate‐P. The frequency of water quality surveys required to obtain an annual nutrient flux with 10% precision was around 15 days for nitrate, 10 days for orthophosphate‐P and total‐P, and about 5 days in the case of particulate‐P. Copyright © 2004 John Wiley & Sons, Ltd.
The MTT assays of bovine retinal pericytes and human microvascular endothelial cells on DLC and Si‐DLC–coated TCPS
Authors: Okpalugo T. I. T. , McKenna E. , Magee A. C. , McLaughlin J. , Brown N. M. D.
Published: September 2004

MTT (Tetrazolium)‐assay suggests that diamond‐like carbon (DLC) and silicon‐doped DLC (Si‐DLC) films obtained under appropriate deposition parameters are not toxic to bovine retinal pericytes, and human microvascular endothelial cells (HMEC). The observed frequency distributions of the optical density (OD) values indicative of cell viability are near Gaussian‐normal distribution. One‐way ANOVA indicates that at 0.05 levels the population means are not significantly different for the coated and control samples. The observed OD values depend on the cell line (cell growth/metabolic rate), possibly cell cycle stage, the deposition parameters‐bias voltage, ion energy, pressure, argon precleaning, and the dopant. For colored thin films like DLC with room temperature photoconductivity and photoelectric effects, it is important to account for the OD contribution from the coating itself. MTT assay, not surprisingly, seems not to be highly sensitive to interfacial cellular interaction resulting from the change in the film's nanostructure, because the tetrazolium metabolism is mainly intracellular and not interfacial. The thin films were synthesized by 13.56 MHz RF‐PECVD using argon and acetylene as source gases, with tetramethylsilane (TMS) vapor introduced for silicon doping. This study could be relevant to biomedical application of the films in the eye, peri‐vascular, vascular compartments, and for cell‐tissue engineering. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 201–208, 2004
Quantitative analysis of interconnectivity of porous biodegradable scaffolds with micro‐computed tomography
Authors: Moore Michael J. , Jabbari Esmaiel , Ritman Erik L. , Lu Lichun , Currier Bradford L. , Windebank Anthony J. , Yaszemski Michael J.
Published: September 2004

Pore interconnectivity within scaffolds is an important parameter influencing cell migration and tissue ingrowth needed to promote tissue regeneration. Methods for assessment of interconnectivity are usually qualitative, restricted to two‐dimensional images, or are destructive. Microcomputed tomography nondestructively provides three‐dimensional (3D) images of intact specimens at high spatial resolutions. We describe an image analysis technique for quantitative assessment of scaffold interconnectivity. Scaffolds were made via a particulate leaching process with 75%, 80%, 85%, and 88% volumetric porogen fractions. Specimens were scanned and resulting 3D, digital images were analyzed with a custom algorithm. A series of virtual, idealized scaffolds were also created for illustration of the algorithm's analysis approach and for its validation. The program calculated accessible void fractions over a range of minimum connection sizes. In real specimens, nearly 100% of the porous volume was connected with outside air for connections greater than or equal to 20 μm in their smallest dimension. In scaffolds made with 75% porogen, the accessible void fraction decreased to 78% if only those connections greater than or equal to 260 μm were considered. The relationship between accessible void fraction and connection size varied as a function of porogen content. The interconnectivity parameter described here may have implications for cell migration and tissue growth into scaffolds. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 258–267, 2004
Pectoral fin and girdle development in the basal actinopterygians Polyodon spathula and Acipenser transmontanus
Authors: Davis Marcus C. , Shubin Neil H. , Force Allan
Published: September 2004

The pectoral fins of Acipenseriformes possess endoskeletons with elements homologous to both the fin radials of teleosts and the limb bones of tetrapods. Here we present a study of pectoral fin development in the North American paddlefish, Polyodon spathula, and the white sturgeon, Acipenser transmontanus, which reveals that aspects of both teleost and tetrapod endoskeletal patterning mechanisms are present in Acipenseriformes. Those elements considered homologous to teleost radials, the propterygium and the mesopterygial radials, form via subdivision of an initially chondrogenic plate of mesenchymal cells called the endoskeletal disc. In Acipenseriformes, elements homologous to the sarcopterygian metapterygium develop separately from the endoskeletal disc as an outgrowth of the endoskeletal shoulder girdle that extends into the posterior margin of the finbud. As in tetrapods, the elongating metapterygium and the metapterygial radials form in a proximal to distal order as discrete condensations from initially nonchondrogenic mesenchyme. Patterns of variation seen in the Acipenseriform fin also correlate with putative homology: all variants from the “normal” fin bauplan involved the metapterygium and the metapterygial radials alone. The primary factor distinguishing Polyodon and Acipenser fin development from each other is the composition of the endoskeletal extracellular matrix. Proteoglycans (visualized with Alcian Blue) and Type II collagen (visualized by immunohistochemistry) are secreted in different places within the mesenchymal anlage of the fin elements and girdle and at different developmental times. Acipenseriform pectoral fins differ from the fins of teleosts in the relative contribution of the endoskeleton and dermal rays. The fins of Polyodon and Acipenser possess elaborate endoskeletons overlapped along their distal margins by dermal lepidotrichia. In contrast, teleost fins generally possess relatively small endoskeletal radials that articulate with the dermal fin skeleton terminally, with little or no proximodistal overlap. J. Morphol. 262:608–628, 2004. © 2004 Wiley‐Liss, Inc.
Coupled‐column liquid chromatography method with photochemically induced derivatization for the direct determination of benzoylureas in vegetables
Authors: Gil García María Dolores , Barranco Martínez Dolores , Martínez Galera María , Parrilla Vázquez Piedad
Published: September 2004

The coupled‐column (LC‐LC) system, consisting of a first column packed with internal surface reversed phase (ISRP) (50×4.6 mm ID) and a Chrompack C18 (100×4.6 mm ID) as second column, allowed the simultaneous determination of five benzoylurea insecticides in dichloromethane (CH2Cl2) extracts of vegetable samples without any clean‐up step. This system was combined with a photochemically induced fluorescence (PIF) post‐column derivatization in order to provide strongly fluorescent photoproducts from the non‐fluorescent benzoylureas. Limits of detection ranged from 0.21 to 0.98 μg L–1 of pesticide (equivalent to 0.14–0.65 μg kg–1 in vegetable samples) and limits of determination ranged from 4.0 to 10.0 μg L–1 (equivalent to 2.7–6.7 μg kg–1). Linearity of the method was established between 2 and 1800 μg L–1, depending upon the compound. Validation of the total method was performed by randomly analyzing recoveries of four vegetable samples (aubergine, cucumber, green bean, and tomato) spiked at two levels of concentration (10.0 and 33.3 μg kg–1). The combination of the LC‐LC system with PIF detection provides a sensitive, selective, and rapid method for the determination of pesticides in vegetable samples at levels lower than the maximum residue levels (MRLs) established for these compounds by Spanish legislation.
Liquid chromatography analysis of monosubstituted sulfobutyl ether‐β‐cyclodextrin isomers on porous graphitic carbon
Authors: Jacquet Romain , Pennanec Rodolphe , Elfakir Claire , Lafosse Michel
Published: September 2004

The retention behaviour of the three positional isomers of monosubstituted sulfobutyl ether‐β‐cyclodextrin was investigated on a porous graphitic carbon (PGC) column. The influence of the mobile phase composition (nature and concentration of organic and electronic modifiers) was studied as well as the effect of column temperature. These hydrophilic and anionic analytes were highly retained on the PGC stationary phase compared to octadecyl bonded phases. The retention is mainly governed by a reversed‐phase mechanism with electronic interaction playing a secondary role. An increase in solute retention and efficiency with temperature was observed. Successful isocratic separation with satisfactory baseline resolution of the three isomers of monosubstituted sulfobutyl ether‐β‐cyclodextrin was achieved at 75°C on a Hypercarb column by using ammonium acetate as electronic modifier in water‐acetonitrile (83 : 17). The chromatographic methodology developed can be easily used for relative quantification of each isomer within a mixture and can be applied for semi‐preparative purification of each one. The evaporative light scattering detector allows the detection of these non UV‐visible absorbing molecules.
Three-dimensional laser display on liquid-crystal medium
Authors: Gonchukov S A , Kompanets I N
Published: September 2004

3D-display implementation on the basis of 2D
acoustooptical laser scanner and volumetric liquid-crystal screen
is presented in this paper. A stack of liquid-crystal layers,
which can be switched into a transmitting or a scattering state,
creates display medium. This display is a powerful and flexible
tool, which can be used in multivarious applications.
High pathological risk of recurrence after surgical resection for hepatocellular carcinoma: An indication for salvage liver transplantation
Authors: Sala Margarita , Fuster Josep , Llovet Josep M. , Navasa Miquel , Solé Manel , Varela María , Pons Fernando , Rimola Antoni , García-Valdecasas Juan Carlos , Brú Concepció , Bruix Jordi
Published: September 2004

Surgical resection and liver transplantation offer a 5-year survival greater than 70% in patients with hepatocellular carcinoma, but the high recurrence rate impairs long-term outcome after resection. Pathological data such as vascular invasion and detection of additional nodules predict recurrence and divide patients into high and low risk profile. Based on this, we proposed salvage liver transplant to resected patients in whom pathology evidenced high recurrence risk even in the absence of proven residual disease. From January 1995 to August 2003 we have evaluated 1,638 patients. Resection was indicated in 77 patients, but only 17 (22%) (all cirrhotics, 14 hepatitis C virus+) were optimal candidates for both resection and transplantation. Of them, 8 exhibited a high risk profile at pathology and were offered transplantation. Among the 8 high risk patients, 7 presented recurrence, compared with only 2 of the 9 at low risk (P = .012). Two of the high risk patients refused transplant and developed multifocal disease during follow-up. The other 6 were enlisted and all but 1 had tumor foci in the explant. Only 1 presented extrahepatic dissemination early after transplant and died 4 months later. The others are free of disease after a median follow-up of 45 months. Two recurrences were detected in low risk patients, 1 of them being transplanted 18 months after surgery. These data in a small series of patients confirm that pathological parameters identify patients at higher risk of recurrence, which allow them to be listed for liver transplantation without proven malignant disease. In conclusion, this policy is clinically effective and could further improve the outcome of resected patients. (Liver Transpl 2004;10:1294-1300.)
Histologic recurrence of chronic hepatitis C virus in patients after living donor and deceased donor liver transplantation
Authors: Shiffman Mitchell L. , Stravitz Todd R. , Contos Melissa J. , Mills Scott A. , Sterling Richard K. , Luketic Velimir A. , Sanyal Arun J. , Cotterell Adrian , Maluf Daniel , Posner Marc P. , Fisher Robert A.
Published: September 2004

Hepatitis C virus (HCV) recurs in nearly all patients after liver transplantation. This recurrence is associated with progressive fibrosis and graft loss. It remains unclear whether the natural course of HCV recurrence is altered in patients who undergo living donor liver transplantation (LDLT). We conducted a prospective, controlled trial using protocol liver biopsies to evaluate the histologic outcome of recurrent HCV in 23 patients who underwent LDLT and 53 patients who underwent transplantation with a deceased donor liver (DDLT) during the same period of time. Patients who did not survive at least 6 months after transplantation or who had hepatocellular carcinoma or any other coexistent liver disease were excluded from analysis. All patients underwent protocol liver biopsy at 6 months and at 12 months and at yearly intervals thereafter. The mean age, sex, racial distribution, and serum HCV RNA and the percentage of patients with genotype 1 were similar in the 2 groups of patients. The model for end-stage liver disease score at the time of transplantation was slightly lower in patients who underwent LDLT, but this difference was not significant. The distribution of immunosuppression agents used, the mean doses of calcineurin agents, the use of mycophenolate mofetil, and the dose and tapering schedule for prednisone were similar in both groups of patients. The mean duration of follow-up was 40 months. No significant difference in either graft or patient survival or the percentage of patients who developed acute rejection was noted in the 2 groups of patients. At 48 months, graft and patient survival were 82% and 82% and 75% and 79% for patients who underwent DDLT and LDLT, respectively. The degree of hepatic inflammation increased stepwise over 3 years but was not significantly different in the 2 patient groups. In contrast, the mean fibrosis score and the percentage of patients with fibrosis increased stepwise after DDLT but appeared to plateau 12 months after LDLT. At 36 months, fibrosis was present in 78% of DDLT patients, and mean fibrosis score was 1.9, compared with 59% with fibrosis and a mean score of .9 after LDLT. In conclusion, these data strongly suggest that fibrosis progression from recurrent HCV is not more severe in patients after LDLT. (Liver Transpl 2004;10:1248-1255.)
Cow's milk allergens identification by two‐dimensional immunoblotting and mass spectrometry
Authors: Natale Massimo , Bisson Carolina , Monti Giovanna , Peltran Amalia , Perono Garoffo Lorenza , Valentini Sabina , Fabris Claudio , Bertino Enrico , Coscia Alessandra , Conti Amedeo
Published: September 2004

Cow's milk allergy (CMA) has become a common disease in early childhood, its prevalence ranging from 1.6% to 2.8% among children younger than 2 years of age. The role of different cow's milk protein (CMP) in the pathogenesis of CMA is still controversial. Even if the proteins most frequently and most intensively recognized by immunoglobulin E (IgE) seem to be the most abundant in milk (caseins and β‐lactoglobulin), with an although great variability all milk proteins appear to be potential allergens, even those that are present in trace amounts (i. e., lactoferrin, IgG, and BSA). In this work proteomics techniques have been applied for CMP allergens analysis. Allergens have been identified by immunoblotting following resolution of CMP components by two‐dimensional electrophoresis. Sera from 20 milk‐allergic subjects, as proven by oral provocation test, CAP‐RAST and skin prick test, have been used for cow's milk major allergen identification. Cow's milk proteins and their isoforms were identified by matrix assisted laser desorption/ionization‐time of flight (MALDI‐TOF)‐mass spectrometry. In our group of patients, the prevalence of CMP allergens, i. e., the total number of subjects sensitized to CMP divided by the total number of the subjects enrolled in the study, was: 55% αs1‐casein, 90% αs2‐casein, 15% β‐casein, 50% κ‐casein, 45% β‐lactoglobulin, 45% BSA, 95% IgG‐heavy chain, 50% lactoferrin, and 0% α‐lactalbumin.
Scheduling recurrent construction
Authors: Schmitt Thomas , Faaland Bruce
Published: September 2004

A problem we call recurrent construction involves manufacturing large, complex, expensive products such as airplanes, houses, and ships. Customers order configurations of these products well in advance of due dates for delivery. Early delivery may not be permitted. How should the manufacturer determine when to purchase and release materials before fabrication, assembly, and delivery? Major material expenses, significant penalties for deliveries beyond due dates, and long product makespans in recurrent construction motivate choosing a release timetable that maximizes the net present value of cash flows. Our heuristic first projects an initial schedule that dispatches worker teams to tasks for the backlogged products, and then solves a series of maximal closure problems to find material release times that maximize NPV. This method compares favorably with other well‐known work release heuristics in solution quality for large problems over a wide range of operating conditions, including order strength, cost structure, utilization level, batch policy, and uncertainty level. Computation times exhibit near linear growth in problem size. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004