bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal total mesorectal excision for rectal cancer is by dissection in front of Denonvilliers' fascia (Br J Surg 2004; 91: 121–123)
Authors: Flati G , Porowska B , Procacciante F
Published: August 2004

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.
Relative Stabilities of Weakly Coordinating Anions: A Computational Study
Authors: Krossing Ingo , Raabe Ines
Published: August 2004

This article describes BP86/SV(P) (DFT) calculations on a representative set of weakly coordinating anions (WCAs) of type [M(L)n]−, their parent neutral Lewis acids M(L)n−1 and their ate complexes with fluoride, that is, [FM(L)n]n−1 (M=B, L=F, OTeF5, C6H5, C6F5, C6H3(CF3)2, CF3; M=P, As, Sb, L=F, OTeF5; M=Al, L=OC(CF3)3). Compounds with fluoride bridges, that is, SbnF5n and [SbnF5n+1]− (n=2, 3, 4), Al2(L)5F and [(L)3Al‐F‐Al(L)3]− (L=OC(CF3)3), (F4C6{1,2‐B(L)2}2, [F4C6{1,2‐B(L)2}2F]−, [F4C6{1,2‐B(L)2}2OMe]− (L=C6F5) were also calculated. Based on these BP86/SV(P) and auxiliary MP2/TZVPP, G2, and CBS‐Q calculations the relative stabilities and coordinating abilities of these WCAs were established with regard to the fluoride ion affinities (FIA) of the parent Lewis acids, the ligand affinity (LA) of the WCAs, the decomposition of a given WCA in the presence of a hard (H+, proton decomposition PD) and a soft electrophile (Cu+, copper decomposition CuD), the position of the HOMO, the HOMO–LUMO gap, and population analyses of the anions providing partial charges for all atoms. To obtain data that is more reliable, the assessed quantities were calculated through isodesmic reactions. If parts of the calculations could not be done isodesmically, higher levels such as MP2/TZVPP, G2, and CBS‐Q were used to obtain reliable values for these reactions. Although the obtained results can not be taken as absolute, the relative ordering of the stabilities of all WCAs will undoubtedly be correct, since a single methodology was chosen for the investigation. To include media effects the decomposition reactions of a subset of 14 WCAs with the SiMe3+ and [Cp2ZrMe]+ ions were also calculated in PhCl and 1,2‐F2C6H4 (COSMO solvation model). We found that in most cases gas‐phase calculations and solution calculations give comparable results for the stability of the anion. Applications of the LA and FIA that allow one to decide, on thermodynamic grounds, which WCA or Lewis acid is the most suitable for a given problem are sketched.
Mouse α1B‐adrenergic receptor is expressed in neurons and NG2 oligodendrocytes
Authors: Papay Robert , Gaivin Robert , McCune Dan F. , Rorabaugh Boyd R. , Macklin Wendy B. , McGrath John C. , Perez Dianne M.
Published: August 2004

α1‐Adrenergic receptors (ARs) are well‐known mediators of the sympathetic nervous system, are highly abundant in the brain, but are the least understood in the central nervous system. The particular cell types in the brain that contain these receptors or their functions are not known because of the lack of high avidity antibodies and selective ligands. We developed transgenic mice that endogenously overexpress the α1B‐AR subtype fused with the enhanced green fluorescent protein (EGFP). Endogenous expression was obtained by using a 3.4 kb fragment of the mouse α1B‐AR promoter. Using this model, we determined cellular localization of the α1B‐AR throughout the brain. The α1B‐AR‐EGFP fusion protein is expressed in neurons throughout the brain and in the Purkinje cells of the cerebellum. The α1B‐AR is also expressed in NG2 oligodendrocyte precursor cells in both neonatal cell cultures and in the adult cerebral cortex, but is weakly expressed in mature oligodendrocytes. The α1B‐AR was not observed in astrocytes or in cerebral vascular smooth muscle, cell types previously suggested to contain α1‐ARs. We conclude that the α1B‐AR is highly abundant throughout the brain, predominately in neurons, and may be involved in the development of the oligodendrocyte. In adult NG2 cells, implicated in stem cell‐like functions, the α1B‐AR may also play a role. This is the first report of a transgenic tagged‐GPCR approach to determine in vivo localization of a receptor. J. Comp. Neurol. 478:1–10, 2004. © 2004 Wiley‐Liss, Inc.
Expression of Islet1 marks the sensory and neuronal lineages in the mammalian inner ear
Authors: Radde‐Gallwitz Kristen , Pan Ling , Gan Lin , Lin Xi , Segil Neil , Chen Ping
Published: August 2004

Several basic helix‐loop‐helix (bHLH) genes have been shown to be essential for the generation of the auditory sensory hair cells or the spiral ganglion (SG) neurons that innervate the hair cells in the cochlea, as well as a variety of cell types in the other nervous systems. However, it remains elusive what cellular context‐dependent mechanisms confer the inner ear–specific neuronal or sensory competency/identities. We explored the possibility that one of the mechanisms responsible for generating cellular diversity in the nervous system through cooperative action of bHLH and LIM‐homeodomain (LIM‐HD) transcriptional factors might also contribute to the inner ear–specific sensory and/or neuronal competency. Here, we show that Islet1 (Isl1), a LIM‐HD protein, is expressed early in the otocyst in the region that gives rise to both the auditory sensory organ, the organ of Corti, and SG neurons. Subsequently, the expression of Isl1 is maintained in SG neurons but is transitory in the sensory lineage. At embryonic day 12 (E12) in mice, the expression of Isl1 marks distinctively the ventral portion of the nascent cochlear epithelium encompassing the primordial organ of Corti. At E13, Isl1 is maintained at relatively high levels in the sensory primordium while down‐regulated in the other regions of the cochlear duct. As the sensory epithelium starts to differentiate, it is down‐regulated in the entire cochlear epithelium. The expression of Isl1 in the developing inner ear reveals an early and likely a common step in the development of both sensory and neuronal lineages of the inner ear, and suggests its potential role in the inner ear‐specific sensory and neuronal cell development. J. Comp. Neurol. 477:412–421, 2004. © 2004 Wiley‐Liss, Inc.
Hypothalamic paraventricular nucleus neurons regulate medullary catecholamine cell responses to restraint stress
Authors: Dayas Christopher V. , Buller Kathryn M. , Day Trevor A.
Published: August 2004

Both physical and psychological stressors recruit catecholamine cells (CA) located in the ventrolateral medulla (VLM) and the nucleus of the solitary tract (NTS). In the case of physical stressors, this effect is initiated by signals that first access the central nervous system at or below the level of the medulla. For psychological stressors, however, CA cell recruitment depends on higher structures within the neuraxis. Indeed, we have recently provided evidence of a pivotal role for the medial amygdala (MeA) in this regard, although such a role must involve a relay, as MeA neurons do not project directly to the medulla. However, some of the MeA neurons that respond to psychological stress have been found to project to the hypothalamic paraventricular nucleus (PVN), a structure that provides significant input to the medulla. To determine whether the PVN might regulate medullary CA cell responses to psychological stress, animals were prepared with unilateral injections of the neurotoxin ibotenic acid into the PVN (Experiment 1), or with unilateral injections of the retrograde tracer wheat germ agglutinin‐gold (WGA‐Au) into the CA cell columns of the VLM or NTS (Experiment 2). Seven days later, animals were subjected to a psychological stressor (restraint; 15 minutes), and their brains were subsequently processed for Fos plus appropriate cytoplasmic markers (Experiment 1), or Fos plus WGA‐Au (Experiment 2). PVN lesions significantly suppressed the stress‐related induction of Fos in both VLM and NTS CA cells, whereas tracer deposits in the VLM or NTS retrogradely labeled substantial numbers of PVN cells that were also Fos‐positive after stress. Considered in concert with previous results, these data suggest that the activation of medullary CA cells in response to psychological stress may involve a critical input from the PVN. J. Comp. Neurol. 478:22–34, 2004. © 2004 Wiley‐Liss, Inc.
Identification and morphological classification of horizontal, bipolar, and amacrine cells within the zebrafish retina
Authors: Connaughton V.P. , Graham D. , Nelson R.
Published: August 2004

Horizontal, bipolar, and amacrine cells in the zebrafish retina were morphologically characterized using DiOlistic techniques. In this method, 1,1′‐dioctadecyl‐3,3,3′,3′‐tetramethylindocarbocyanine perchlorate (DiI)‐coated microcarriers are shot at high speed onto the surfaces of living retinal slices where the DiI then delineates axons, somata, and dendrites of isolated neurons. Zebrafish retinal somata were 5–10 μm in diameter. Three horizontal cell types (HA‐1, HA‐2, and HB) were identified; dendritic tree diameters averaged 25–40 μm. HA somata were round. Cells classified as HA‐2 were larger than HA‐1 cells and possessed an axon. HB somata were flattened, without an axon, although short fusiform structure(s) projected from the soma. Bipolar cells were separated into 17 morphological types. Dendritic trees ranged from 10 to 70 μM. There were six Bon types with axon boutons only in the ON sublamina of the inner plexiform layer (IPL), and seven Boff types with axon boutons or branches only in the OFF sublamina. Four types of bistratified bipolar cells displayed boutons in both ON and OFF layers. Amacrine cells occurred in seven types. Aoff cells (three types) were monostratified and ramified in the IPL OFF sublamina. Dendritic fields were 60–150 μM. Aon pyriform cells (three types) branched in the ON sublamina. Dendritic fields were 50–170 μM. Adiffuse cells articulated processes in all IPL strata. Dendritic fields were 15–90 μM. These findings are important for studies examining signal processing in zebrafish retina and for understanding changes in function resulting from mutations and perturbations of retinal organization. J. Comp. Neurol. 477:371–385, 2004. Published 2004 Wiley‐Liss, Inc.
Expression of vanilloid receptor TRPV1 in the rat trigeminal sensory nuclei
Authors: Bae Yong Chul , Oh Jung Min , Hwang Se Jin , Shigenaga Yoshio , Valtschanoff Juli G.
Published: August 2004

Little is known about the central projection patterns of trigeminal afferent neurons expressing the vanilloid receptor TRPV1 and their coexpression of neuromodulatory peptides. To address these issues, we examined the distribution of TRPV1‐positive neurons in the trigeminal ganglion (TG) and trigeminal sensory nuclei principalis (Vp), oralis (Vo), interpolaris (Vi), and caudalis (Vc) in the rat via light and electron microscopy. In addition, we studied the colocalization of TRPV1‐positive neurons with substance P (SP) and calcitonin gene‐related peptide (CGRP) via confocal microscopy. In TG, only small and medium‐sized neurons were immunopositive for TRPV1. The staining for TRPV1 was found in axon collaterals in the dorsal parts of Vp, Vo, and Vi and in terminals and fibers throughout lamina I and the outer zone of lamina II (IIo) of Vc. With electron microscopy, TRPV1‐positive fibers in the ascending and descending trigeminal tracts were found to be unmyelinated. Almost all TRPV1‐positive terminals in Vc contained numerous large dense‐core vesicles and formed synaptic contacts with single small dendrites. Multiple immunofluorescence revealed a high degree of colocalization of TRPV1 with SP and CGRP in TG neurons as well as in fibers and terminals confined to laminae I and IIo of Vc. These results suggest that the central projections of unmyelinated (C) afferents sensitive to noxious heat and capsaicin are organized differently between Vc and the rostral trigeminal nuclei and that Vc may play a role in the development of hyperalgesia. J. Comp. Neurol. 478:62–71, 2004. © 2004 Wiley‐Liss, Inc.
Localization of myosin phosphatase target subunit 1 in rat brain and in primary cultures of neuronal cells
Authors: Lontay Beáta , Serfőző Zoltán , Gergely Pál , Ito Masaaki , Hartshorne David J. , Erdődi Ferenc
Published: August 2004

Myosin phosphatase (PP1M) is composed of the δ isoform of the PP1 catalytic subunit (PP1cδ), the myosin phosphatase target subunit (MYPT), and a 20 kDa subunit. Western blots detected higher amounts of the MYPT1 isoform compared to MYPT2 in whole brain extracts. The localization of MYPT1 was studied in rat brain and in primary cell cultures of neurons using specific antibodies. Analysis of lysates of brain regions for MYPT1 and PP1M by Western blots using anti‐MYPT1 antibodies and by phosphatase assays with myosin as substrate suggested a ubiquitous distribution. Immunohistochemistry of tissue sections revealed that MYPT1 was distributed in all areas of the brain, with staining observed in many different cell types. Depending on the method used for fixation, the MYPT1 appeared with varying intensity in nuclei, in nucleoli, and in the cytoplasm. In primary hippocampal cultures, MYPT1 was identified by confocal microscopy in the cytoplasm and in the nucleus, whereas a predominantly cytoplasmic localization was found in cochlear nucleus cells. In cultured cells, MYPT1 and PP1cδ colocalized with synaptophysin. PP1M activity was high in synaptosomes isolated from the cerebral cortex, but was relatively low in the postsynaptic densities. The interaction of MYPT1 with synaptophysin and with known partners (Rho‐kinase, PP1cδ) in brain extracts was shown by immunoprecipitation with anti‐MYPT1. Pull‐down assays from synaptosomes, using GST‐MYPT1, also confirmed these interactions. In conclusion, the widespread cellular and subcellular localization of MYPT1 implies that PP1M may play an important role in the dephosphorylation of key regulatory proteins in neuronal cells. J. Comp. Neurol. 478:72–87, 2004. © 2004 Wiley‐Liss, Inc.
Neuroanatomical distribution of huntingtin‐associated protein 1‐mRNA in the male mouse brain
Authors: Fujinaga Ryutaro , Kawano June , Matsuzaki Yumiko , Kamei Kyoko , Yanai Akie , Sheng Zijing , Tanaka Mayumi , Nakahama Ken‐Ichi , Nagano Mamoru , Shinoda Koh
Published: August 2004

Huntingtin‐associated protein 1 (HAP1) was identified as an interactor of the gene product (Huntingtin) responsible for Huntington's disease and found to be a core component of the stigmoid body. Even though HAP1 is highly expressed in the brain, detailed information on HAP1 distribution has not been fully described. Focusing on the neuroanatomical analysis of HAP1‐mRNA expression using in situ hybridization histochemistry, the present study clarified its detailed regional distribution in the entire mouse brain. Mouse HAP1 (Hap1)‐mRNAs were abundantly expressed in the limbic‐related forebrain regions and midline/periventricular brainstem regions including the olfactory bulb, limbic‐associated cortices, hippocampus, septum, amygdala, bed nucleus of the stria terminalis, preoptico‐hypothalamic regions, central gray, raphe nuclei, locus coeruleus, parabrachial nuclei, nucleus of the solitary tract, and area postrema. In contrast, little expression was detected in the striatum and thalamus, implying that Hap1 is associated with neurodegeneration‐sparing regions rather than target lesions in Huntington's disease. The distribution pattern, resembling that of the stigmoid body, suggests that HAP1 and the stigmoid body are implicated in protection from neuronal death rather than induction of neurodegeneration in Huntington's disease, and that they play an important role in integrating instinct behaviors and underlying autonomic, visceral, arousal, drive, memory, and neuroendocrinergic functions, particularly during extensive homeostatic or emotional processes. These data will provide an important morphological base for a future understanding of functions of HAP1 and the stigmoid body in the brain. J. Comp. Neurol. 478:88–109, 2004. © 2004 Wiley‐Liss, Inc.
Mineral soil surface crusts and wind and water erosion
Authors: Singer Michael J. , Shainberg Isaac
Published: August 2004

The ﬁrst few millimetres of soil largely control the soil's response to the eroding forces of wind and water. The tendency of soils to form surface seals and crusts inﬂuences the processes of wind and water erosion differently. For wind, dry particle size distribution and particle organization determine the shear strength and threshold wind velocity necessary to initiate particle movement. In loams and clay loams, seals and crusts decrease roughness but increase surface soil strength, generally decreasing wind erosion. Conversely, in sand and sandy loams, loose erodible sandy material may either deposit on the crust and is subject to erosion or it may disrupt the crust, accelerating the erosion process. For water erosion, particle size distribution and structure determine inﬁltration rate, time to ponding, and energy required for soil particle detachment. Seals and crusts tend to decrease inﬁltration rate and time to ponding thus increasing overland ﬂow and soil erosion. This paper brieﬂy reviews how permanent and time‐dependent soil properties inﬂuence surface seals and crusts and how these affect soil erosion by wind and water. The tendency of a soil to form a seal and crust depends to some degree on the time‐dependent property of soil structural stability, which tends to increase with increasing clay content and smectitic mineralogy which are permanent properties. These permanent properties and their effect on structure are variable depending on dynamic properties of exchangeable sodium percentage and soil solution electrical conductivity. Antecedent water content prior to irrigation or rainfall, rate of wetting before an erosive event and aging, the time between wetting and an erosive event, greatly inﬂuence the response of soil structure to raindrop impact. The effect of these dynamic processes is further inﬂuenced by the static and dynamic properties of the soil. Weak structure will be less inﬂuenced by wetting rate than will a soil with strong structure. Process‐based models of wind and water erosion need to consider the details of the interactions between soil static and dynamic properties and the dynamic processes that occur prior to erosive events. Copyright © 2004 John Wiley & Sons, Ltd.
A conceptual framework of faculty trust and participation in governance
Authors: Pope Myron L.
Published: August 2004

There is a link between faculty trust of administration and their subsequent levels of participation in the governance process.
Xrcc3 is recruited to DNA double strand breaks early and independent of Rad51
Authors: Forget Anthony L. , Bennett Brian T. , Knight Kendall L.
Published: August 2004

Rad51‐mediated homologous recombination (HR) is essential for maintenance of genome integrity. The Xrcc3 protein functions in HR DNA repair, and studies suggest it has multiple roles at different stages in this pathway. Defects in vertebrate XRCC3 result in elevated levels of spontaneous and DNA damage‐induced chromosomal abnormalities, as well as increased sensitivity to DNA damaging agents. Formation of DNA damaged‐induced nuclear Rad51 foci requires Xrcc3 and the other Rad51 paralog proteins (Rad51B, Rad51C, Rad51D, Xrcc2), thus supporting a model in which an early function of Xrcc3 involves promoting assembly of active Rad51 repair complexes. However, it is not known whether Xrcc3 or other Rad51 paralog proteins accumulate at DNA breaks, and if they do whether their stable association with breaks requires Rad51. Here we report for the first time that Xrcc3 forms distinct foci in human cells and that nuclear Xrcc3 begins to localize at sites of DNA damage within 10 min after radiation treatment. RNAi‐mediated knock down of Rad51 has no effect on the DNA damage‐induced localization of Xrcc3 to DNA breaks. Our data are consistent with a model in which Xrcc3 associates directly with DNA breaks independent of Rad51, and subsequently facilitates formation of the Rad51 nucleoprotein filament. © 2004 Wiley‐Liss, Inc.
Antibacterial activities and total phenolic contents of grape pomace extracts
Authors: Özkan Gülcan , Sagdiç Osman , Göktürk Baydar Nilgün , Kurumahmutoglu Zehra
Published: August 2004

The aim of this study was to determine the total phenolic contents and antibacterial effects of grape pomace extracts (cultivars Emir and Kalecik karasi) against 14 bacteria, and the effects of the extracts on the growth and survival of two of the bacteria during storage. The total phenolic contents of grape pomace of Emir and Kalecik karasi cultivars extracted with acetone/water/acetic acid (90:9.5:0.5) were 68.77 and 96.25 mg GAE g−1, respectively. The agar well diffusion method was used to test the antibacterial activity of the extracts at 1, 2.5, 5, 10 and 20% (w/v) concentrations in methanol on spoilage and pathogenic bacteria including Aeromonas hydrophila, Bacillus cereus, Enterobacter aerogenes, Enterococcus faecalis, Escherichia coli, Escherichia coli O157:H7. Mycobacterium smegmatis, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus and Yersinia enterocolitica. All the bacteria tested were inhibited by extract concentrations of 2.5, 5, 10 and 20%, except for Y enterocolitica which was not inhibited by the 2.5% concentration. However, pomace extracts at 1% concentration had no antibacterial activity against some of the bacteria. According to the agar well diffusion method, E coli O157:H7 was the most sensitive of the bacteria. Generally, using the serial dilution method, while the extracts at 0.5% concentration had bacteriostatic activities on E coli O157:H7 and S aureus, the extracts appeared to have bactericidal effects at 1 and 2.5% concentrations. In accordance with this method, S aureus was more sensitive than E coli O157:H7 to the extracts. Copyright © 2004 Society of Chemical Industry
Investigation of foam‐active polypeptides during beer fermentation
Authors: Kordialik‐Bogacka Edyta , Ambroziak Wojciech
Published: August 2004

During ale fermentation there was an accumulation of total and hydrophobic polypeptides in the foam relative to the wort. Comparisons were made not only of the total and hydrophobic polypeptide contents but also of the molecular weights of these polypeptides present in wort, partially fermented wort and its concomitant foam. Wort, fermented wort and foam fractions had very similar polypeptide compositions with a major group having molecular weights of 40–43 kDa. Material of molecular weight in the range of 5–17 kDa and at 66 kDa was also detected. The polypeptides accumulated in foam displayed both hydrophobic and non‐hydrophobic character. The presence of yeast polypeptides in foam was confirmed. Comparison was also made between the fermentations of 10°Plato and 15°Plato wort. The results of the work may contribute to a better understanding of the mechanism of foam formation during beer fermentation, leading to reduced foaming and enabling an increase in the working capacities of fermenters. Copyright © 2004 Society of Chemical Industry
Production of gluten‐free bread using soybean flour
Authors: Ribotta Pablo D , Ausar Salvador F , Morcillo Martin H , Pérez Gabriela T , Beltramo Dante M , León Alberto E
Published: August 2004

The effect of soybean flour on gluten‐free bread quality was studied. Full‐fat enzyme‐active, semiactive and inactive soybean flours were evaluated. Active soybean flour improved the volume and structure of gluten‐free bread, while semiactive and inactive soybean flours did not have positive effects on bread quality. The particle size and concentration of the soybean flours also affected bread quality. Levels of addition between 125 and 150 g kg−1 and particle sizes between 90 and 120 µm of active soybean flour yielded the best results. Heating the active soybean flour destroyed its improving effect. The analysis of proteins by sodium dodecyl sulphate polyacrylamide gel electrophoresis and size exclusion chromatography showed that heating soybean flour at 60–200°C caused protein aggregation. The overall results indicated that the addition of active soybean flour improved gluten‐free bread quality, and this effect seemed to be due to both the structural proteins and the enzymatic activities of the soybean flour. Copyright © 2004 Society of Chemical Industry
A DFT Quantum‐Chemical Study of the Structure of Precursors and Active Sites of Catalyst Based on 2,6‐Bis(imino)pyridyl Fe(II) Complexes
Authors: Zakharov Ivan I. , Zakharov Vladimir A.
Published: August 2004

Summary: A DFT method has been applied for quantum‐chemical calculations of the molecular structure of charge‐neutral complex LFeMe(μMe)2AlMe2 which is formed in system LFeMe2 + AlMe3 (L = 2,6‐bis(imino)pyridyl). Calculations suggested the formation of highly polarized complex LFeMe(μMe)2AlMe2 (II) in system LFeMe2 + AlMe3, characterized by r(FeμMe) = 3.70 Å and r(AlμMe) = 2.08 Å and deficient electron density on fragment [LFeMe]Q (Q = +0.80 e). Polarization of the complex progresses with the bounding of two AlMe3 molecules (complex LFeMe(μMe)2AlMe2 · 2AlMe3 (III)) and with replacement of AlMe3 by MeAlCl2 (complex LFeMe(μMe)2AlCl2 (IV)). The activation energy of ethylene insertion into the FeMe bond of these complexes has been calculated. It was found that the heat of π‐complex formation increases with increasing of polarization extent in the order II < III < IV. Activation energy of the insertion of coordinated ethylene into FeMe bond decreases in the same order: II > III > IV.

Calculated model complex (NH3)3FeMe2; tridentate bis(imino)pyridyl ligand was substituted by three coplanar NH3 groups.

image

Calculated model complex (NH3)3FeMe2; tridentate bis(imino)pyridyl ligand was substituted by three coplanar NH3 groups.
Ignition Characteristics of Metastable Intermolecular Composites
Authors: Asay Blaine W. , Son Steven F. , Busse James R. , Oschwald David M.
Published: August 2004

Metastable Intermolecular Composite (MIC) materials are comprised of a mixture of oxidizer and fuel with particle sizes in the nanometer range. They are a subclass of materials known as thermites. The mechanism responsible for the propagation of reaction in loose compacts is not well understood. We have conducted a series of experiments using high‐speed photography and pressure transducers in an attempt to identify the dominant mechanism. We studied a mixture of aluminum and molybdenum trioxide. Of the four possible candidates (radiation, convection, conduction, and acoustic/compaction), these preliminary studies identify convection as the most likely. However, the extent of contribution of the other modes is not yet known and this will receive further study.
Tetrazine Explosives
Authors: Chavez David E. , Hiskey Michael A. , Naud Darren L.
Published: August 2004

The synthesis and properties of various 1,2,4,5‐tetrazine explosives and energetic materials are described. These are the nitrate and perchlorate salts of 3,6‐diguanidino‐1,2,4,5‐tetrazine, the nitrate and perchlorate salts of 3,6‐diguanidino‐1,2,4,5‐tetrazine‐1,4‐di‐N‐oxide, 3,6‐bis(1H‐1,2,3,4‐tetrazol‐5‐ylamino)‐1,2,4,5‐tetrazine and its 1,4‐di‐N‐oxide derivative, 3,3′‐azobis(6‐amino‐1,2,4,5‐tetrazine) and its oxidation products.
Work‐Principle Model for Predicting Toxic Fumes of Nonideal Explosives
Authors: Wieland Michael S.
Published: August 2004

The work‐principle from thermodynamics was used to formulate a model for predicting toxic fumes from mining explosives in underground chamber tests, where rapid turbulent combustion within the surrounding air noticeably changes the resulting concentrations. Two model constants were required to help characterize the reaction zone undergoing rapid chemical transformations in conjunction with heat transfer and work output: a stoichiometry mixing fraction and a reaction‐quenching temperature. Rudimentary theory with an unsteady uniform concentration gradient was taken to characterize the combustion zone, yielding 75% for the mixing fraction. Four quenching temperature trends were resolved and compared to test results of ammonium nitrate compositions with different fuel‐oil percentages (ANFO). The quenching temperature 2345 K was the optimum choice for fitting the two major components of fume toxicity: carbon monoxide (CO) and total nitrogen oxides (NOX). The resulting two‐constant model was used to generate comparisons for test results of ANFO compositions with additives. Though respectable fits were usually found, charge formulations which reacted weakly could not be resolved numerically. The work‐principle model yields toxic concentrations for a range of charge formulations, making it a useful tool for investigating the potential hazard of released fumes and reducing the risk of unwanted incidents.
Low‐temperature thermodynamic properties of one‐dimensional disordered electron lattice system
Authors: Slavin V.
Published: August 2004

The ground state and low‐temperature thermodynamic properties of a one‐dimensional Generalized Wigner crystal on disordered host‐lattice have been studied. It is established that the spectrum of elementary excitations has a gapless structure. An instability of the ground state with respect to arbitrary small disordering of host‐lattice is revealed. This instability leads to long‐range correlations breaking. An influence of long‐range action of the inter‐particle repulsion potential on thermodynamic properties is studied. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of YAB:Cr3+ nanocrystallite sizes on two‐photon absorption of YAB:Cr3+
Authors: Majchrowski A. , Kityk I. V. , Ebothé J.
Published: August 2004

An influence of nanocrystalline sizes of YAB:Cr particles incorporated within olygoetheracrylate polymer matrix on the two‐photon absorption was investigated. Maximal values of the two‐photon absorption diagonal tensor component was observed at low temperatures (about 4.2 K) and corresponded to concentration of the YAB:Cr NC about the 3% by weight and about 22 nm in sizes. The Cr3+ ions inside investigated NC play the crucial role in the observed nonlinear optical phenomena. The observed temperature dependence is explained within a model of anharmonic electron–phonon contribution in the nanocrystallites. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependence of interatomic separation for alkali halides
Authors: Fang Zheng‐Hua
Published: August 2004

A simple relation for predicting temperature dependence of the interatomic separation in alkali halides is developed based on the diffusional driving force models reported in the literature. The input parameters needed for the calculation are the volume thermal expansion coefficient and the isothermal Anderson–Gruneisen parameter both at room temperature and zero‐pressure, which are available from the literature. The tests on eight alkali halide crystals from room temperature to their melting points demonstrate that the agreement between the calculated results obtained by this relation and the corresponding experimental data is excellent. The comparisons with the other similar relations given by earlier workers also lent support strongly to the applicability of the relation presented here for the temperature dependence of interatomic separation for alkali halides. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Perinatally lethal, short‐limbed dwarfism with distinct features—Schneckenbecken dysplasia
Authors: Varkey J. J. , Jones R. A. K.
Published: August 2004

The clinical, radiographical and histological features are described for a case of Schneckenbecken dysplasia, presenting antenatally with increased nuchal thickness and severe skeletal dysplasia. Intrauterine death occurred in the third trimester and the precise diagnosis was made postmortem. This is the first case reported in the UK. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Opioids in chronic non‐cancer pain, indications and controversies
Authors: Breivik Harald
Published: August 2004

The use of opioid analgesics for long term management of chronic non‐cancer pain is now an accepted, although still a controversial medical practice. In some well selected patients with long‐lasting or recurrent pain, severe enough to markedly reduce their quality of life, and for whom no other more effective and less risky therapy is available, opioid analgesics may reduce intensity of pain, increase functioning and improve quality of life for prolonged periods. The type of pain and pain history of the patients do not predict reliably the chance of long term success or risk of complications from opioid therapy. However, the outlook for successful long term opioid therapy is better in a patient with a stable psychosocial situation having nociceptive type pain that is markedly relieved by a moderate dose of a long lasting oral or transdermal opioid, than a patient from a complex and unstable psychosocial background having neuropathic type pain that is relieved only partly by a higher dose of a potent opioid. When a patient is managed by a multidisciplinary team, the compliance is better and risk of loss of control and complications are less than when a single doctor is managing the patient. The evidence base for this type of pain management is meagre because the needed randomized controlled trials, which ideally should last for several years, have not been performed. Therefore a number of national and international guidelines are being published, recommending experts' opinion on appropriate use and responsible follow‐up of long term treatment with opioids for chronic non‐cancer pain.
What to learn from in vivo opioidergic brain imaging?
Authors: Sprenger Till , Berthele Achim , Platzer Stefan , Boecker Henning , Tölle Thomas Rudolf
Published: August 2004

Ligand‐PET studies are attracting increasing interest in experimental and clinical research. As the most elaborated of PET techniques, ligand‐PET allows the demonstration of receptor distributions, and thus, the delineation of neurochemical pathologies in the disease state. Recent developments are promising that ligand‐PET will even allow to characterize dynamic and short‐term changes in neurotransmission and will tremendously add to the understanding of neurophysiology on the receptor level. In pain studies, mainly the μ‐opioidergic agonist {11C}‐carfentanil and the unspecific opioid receptor antagonist {11C}‐diprenorphine are applied. Utilizing these ligands the thalamus, prefrontal and cingulate cortex, basal ganglia and midbrain structures have been shown to possess high amounts of opioidergic receptors in vivo and it is well accepted, that the receptor density is higher in projections of the medial than those of the lateral pain system. Changes in receptor availability were observed in patients suffering from chronic pain. Rheumatoid arthritis, trigeminal neuralgia and central poststroke pain (CPSP) all lead to decreased ligand binding in pain processing regions during the painful period in comparison to pain free intervals or healthy subjects. These decreases may either be the consequence of increased endogenous release or indicate receptor internalization/down‐regulation or loss of neurons carrying these receptors. Recent studies also evidenced {11C}‐carfentanil binding changes due to acute experimental pain. One possible interpretation of these changes is that the PET‐ligand might be displaced by endogenous opioidergic ligands. One major region, where this “ligand displacement” was observed, was the thalamus. These findings highlight the importance of the opioidergic system in pain processing and the power of ligand‐PET to advance the understanding of pain.
Altered processing of pain‐related information in patients with fibromyalgia
Authors: Montoya Pedro , Pauli Paul , Batra Anil , Wiedemann Georg
Published: August 2004

Pressure pain thresholds (PPTs) and event‐related potentials (ERPs) elicited by emotional words were analyzed in 12 patients with fibromyalgia (FM) and 12 matched healthy subjects. PPTs were assessed at the middle finger of both hands, before and after the experiment. Overall, FM patients and healthy subjects did not differ in PPT. Nevertheless, FM patients as compared with healthy controls were characterized by a significant enhancement of pain sensitivity from the beginning to the end of the experiment indicating a long lasting sensitization due to repeated stimulation. ERPs were recorded during a language decision task where subjects had to react to unpleasant pain‐related and emotionally neutral words depending on syntactic or orthographic cues. An emotional category effect was observed on N400 and P300 components of the ERP, indicating that unpleasant words elicited more positive amplitudes than neutral words. A significant group effect was observed on P200 amplitudes, showing reduced amplitudes in FM patients as compared to healthy controls. Furthermore, unpleasant pain‐related compared to neutral words triggered significantly enhanced late positive slow waves in healthy controls, while a comparable effect was not found in FM patients. The ERP and PPT data suggest that FM patients are characterized by an altered cognitive processing of pain‐related information and by an abnormal adaptation to mechanical pain stimuli, respectively.
PTSD symptoms, demographic characteristics, and functional status among veterans treated in VA primary care clinics
Authors: Magruder Kathryn M. , Frueh B. Christopher , Knapp Rebecca G. , Johnson Michael R. , Vaughan James A. , Carson Toni Coleman , Powell Donald A. , Hebert Renée
Published: August 2004

We hypothesized that PTSD symptomatology would have an inverse relationship with functional status and would vary as a function of sociodemographic variables. Primary care patients (N = 513) at two VA Medical Centers were randomly selected and recruited to participate. After adjustment for other demographic variables. PTSD symptom levels were significantly related to age (younger patients had more severe symptoms), employment status (disabled persons had higher symptom levels), war zone experience, and clinic location. PTSD symptomatology was inversely related to mental and physical functioning, even after control for potential confounding. These findings have implications for screening and service delivery in VA primary care clinics, and support the more general finding in the literature that PTSD is associated with impaired functioning.
Posttraumatic stress disorder symptoms and parenting satisfaction among a national sample of male Vietnam veterans
Authors: Samper Rita E. , Taft Casey T. , King Daniel W. , King Lynda A.
Published: August 2004

This study examined relationships between posttraumatic stress disorder (PTSD) symptoms and parenting satisfaction. Total PTSD severity scores and avoidance and emotional numbing symptoms were significantly associated with parenting satisfaction. These associations remained significant even after controlling for partner violence, major depression, and alcohol abuse/dependence. Results suggest that higher levels of PTSD symptoms and avoidance and emotional numbing symptoms in particular may have a deleterious effect on parent–child relationship satisfaction.
Posttraumatic growth in child survivors of a road traffic accident
Authors: Salter Emma , Stallard Paul
Published: August 2004

Although the negative consequences of trauma have been well researched and described, posttraumatic growth has only recently come to the attention of researchers. This paper considers whether children (aged 7–18 years) who have been involved in a road traffic accident can experience posttraumatic growth outcomes. From 158 children who took part in an interview, qualitative analysis of interview notes found that 67 (42%) reported some aspect of posttraumatic growth, most notably in terms of their philosophy of life. Of these, 25 (37%) were also assessed as experiencing posttraumatic stress disorder.
Investigation of transport processes across the sea surface microlayer by infrared imagery
Authors: Schimpf U. , Garbe C. , Jähne B.
Published: August 2004

Heat is used as a proxy tracer for gases to study the transport processes across the sea surface microlayer. Infrared imaging techniques permit fast measurements of heat transfer velocities and give an insight into the transport mechanisms across the thermal sublayer. The observed fluctuations of the sea surface temperature suggest that surface renewal is the major turbulent transport mechanism at medium and high wind speeds. The scale space analysis of the temperature patterns at the sea surface with respect to their contribution to the skin‐bulk temperature difference shows the turbulent nature of the transport process. Large‐scale turbulence dominates the transport at low friction velocities, whereas small‐scale turbulence is more dominant at higher wind friction. The skin‐bulk temperature difference is estimated by fitting the measured sea surface temperature distribution with a PDF function based on a surface renewal model. Periodic heat flux switching in the wind‐wave flume delivers independent estimates of surface and bulk temperature and verifies the statistical approach, whereas at very low wind speeds and film‐covered surfaces the statistical method underestimates the skin‐bulk temperature difference across the thermal sublayer. The large scatter of the transfer velocities when plotted versus wind speed indicates that not only the wind shear but also other processes such as the wave field and surfactants influences near‐surface turbulence and thus air‐water gas transfer.
Sea level pressure variability over the southern Indian Ocean inferred from a glaciochemical record in Princess Elizabeth Land, east Antarctica
Authors: Xiao Cunde , Mayewski Paul A. , Qin Dahe , Li Zhongqin , Zhang Mingjun , Yan Yuping
Published: August 2004

A 250‐year, high‐resolution, multivariate ice core record from LGB65 (70°50′07″S, 77°04′29″E; 1850 m asl), Princess Elizabeth Land (PEL), is used to investigate sea level pressure (SLP) variability over the southern Indian Ocean (SIO). Empirical orthogonal function (EOF) analysis reveals that the first EOF (EOF1) of the glaciochemical record from LGB65 represents most of the variability in sea salt throughout the 250‐year record. EOF1 is negatively correlated (95% confidence level and higher) to instrumental mean sea level pressure (MSLP) at Kerguelen and New Amsterdam islands, SIO. On the basis of comparison with NCEP/NCAR reanalysis, strong correlations were found between sea‐salt variations and a quasi‐stationary low that lies to the north of Prydz Bay, SIO. Comparison with a 250‐year‐long summer transpolar index (STPI) inferred from sub‐Antarctic tree ring records reveals strong coherency. Decadal‐scale SLP variability over SIO suggests shifting of the polar vortex. Prominent decadal‐scale deepening of the southern Indian Ocean low (SIOL) exists circa 1790, 1810, 1835, 1860, 1880, 1900, and 1940 A.D., continuously after the 1970s, and prominent weakening circa 1750, 1795, 1825, 1850, 1870, 1890, 1910, and 1955 A.D. The LGB65 sea‐salt record is characterized by significant decadal‐scale variability with a strong ∼21‐year periodic structure (99.9% confidence level). The relationship between LGB65 sea salt and solar irradiance changes shows that this periodicity is possibly the solar Hale cycle (22 years).
The partitioning of acetone to different types of ice and snow between 198 and 223 K
Authors: Bartels‐Rausch T. , Guimbaud C. , Gäggeler H. W. , Ammann M.
Published: August 2004

The air – ice partitioning of acetone to four different laboratory ice and natural snow samples was investigated at a surface coverage between 0.1 and 6% and temperatures between 198 and 223 K using a chromatographic column coupled to an atmospheric pressure chemical ionization mass spectrometer. The adsorption enthalpy and entropy were obtained from the temperature dependence of the measured partitioning coefficient. No significant difference was found among the four ice and snow samples substantially differing in crystallinity and chemical composition. An average adsorption enthalpy of 52 ± 2 kJ/mol and a standard adsorption entropy of −96 ± 16 J/(mol K) was obtained. A short outlook on partitioning coefficients under atmospheric conditions is given, and the adsorption mechanism is discussed based on the adsorption entropy and enthalpy found.
Long‐range transport of Siberian biomass burning emissions and impact on surface ozone in western North America
Authors: Jaffe Dan , Bertschi Isaac , Jaeglé Lyatt , Novelli Paul , Reid Jeffrey S. , Tanimoto Hiroshi , Vingarzan Roxanne , Westphal Douglas L.
Published: August 2004

During the summer of 2003, biomass fires burned a large area of Siberia, the largest in at least 10 years. We used the NRL Aerosol Analysis and Prediction System (NAAPS) model to forecast the transport of the smoke from these fires. Transport of these airmasses to North America was confirmed by aircraft and surface observations. The fires resulted in enhancements in summer background CO and O3of 23–37 and 5–9 ppbv, respectively, at 10 sites in Alaska, Canada and the Pacific Northwest. From the area burned, we estimate that the Siberian fires generated 68 Tg of CO and 0.82 Tg of NOx(as N). In addition, we show that the background O3enhancement contributed to an exceedance of the ozone air quality standard in the Pacific Northwest. These results show that regional air quality and health are linked to global processes, including climate, forest fires and long‐range transport of pollutants.
Observed one‐dimensional return stroke propagation speeds in the bottom 170 m of a rocket‐triggered lightning channel
Authors: Olsen R. C. , Jordan D. M. , Rakov V. A. , Uman M. A. , Grimes N.
Published: August 2004

The return‐stroke propagation speeds of five strokes from a seven‐stroke triggered lightning flash are measured, with a 2 ns sampling interval, using a vertical array of photodiodes. Various methods for determining the reference point to be tracked are explored, and the speed is seen to vary over nearly an order of magnitude depending upon which method is chosen. The speeds are generally in agreement with the values found in the literature. The return‐stroke speed appears to increase with height and then decrease with height in four of the five strokes examined.