bluuebunny/crossref_metadata_2025 huggingface dataset:
UPPER SEMICONTINUITY OF ATTRACTORS FOR THE KLEIN–GORDON–SCHRÖDINGER EQUATION
Authors: LU KENING , WANG BIXIANG
Published: March 2005

In this paper, we consider the Klein–Gordon–Schröodinger equation defined on Rn (n ≤ 3) and Ωm = {x ∈ Rn : |x| ≤ m}. Let [Formula: see text] and [Formula: see text] be the global attractors of the equation corresponding to Rn and Ωm, respectively. Then we prove that for any neighborhood U of [Formula: see text], the global attractor [Formula: see text] enters U when m is large enough.
Development of a three-dimensional physiological model of the internal anal sphincter bioengineered in vitro from isolated smooth muscle cells
Authors: Hecker Louise , Baar Keith , Dennis Robert G. , Bitar Khalil N.
Published: March 2005

Fecal incontinence affects people of all ages and social backgrounds and can have devastating psychological and economic consequences. This disorder is largely attributed to decreased mechanical efficiency of the internal anal sphincter (IAS), yet little is known about the pathophysiological mechanisms responsible for the malfunction of sphincteric smooth muscle at the cellular level. The object of this study was to develop a three-dimensional (3-D) physiological model of the IAS bioengineered in vitro from isolated smooth muscle cells. Smooth muscle cells isolated from the IAS of rabbits were seeded in culture on top of a loose fibrin gel, where they migrated and self-assembled in circumferential alignment. As the cells proliferated, the fibrin gel contracted around a 5-mm-diameter SYLGARD mold, resulting in a 3-D cylindrical ring of sphincteric tissue. We found that 1) the bioengineered IAS rings generated a spontaneous basal tone, 2) stimulation with 8-bromo-cAMP (8-Br-cAMP) caused a sustained decrease in the basal tone (relaxation) that was calcium-independent, 3) upon stimulation with ACh, bioengineered IAS rings showed a calcium- and concentration-dependent peak contraction at 30 s that was sustained for 4 min, 4) addition of 8-Br-cAMP induced rapid relaxation of ACh-induced contraction and force generation of IAS rings, and 5) bioengineered sphincter rings show striking functional differences when compared with bioengineered rings made from isolated colonic smooth muscle cells. This is the first report of a 3-D in vitro model of a gastrointestinal smooth muscle IAS. Bioengineered IAS rings demonstrate physiological functionality and may be used in the elucidation of the mechanisms causing sphincter malfunction.
C-type Natriuretic Peptide Inhibits L-type Ca2+Current in Rat Magnocellular Neurosecretory Cells by Activating the NPR-C Receptor
Authors: Rose Robert A. , Anand-Srivastava Madhu B. , Giles Wayne R. , Bains Jaideep S.
Published: March 2005

Magnocellular neurosecretory cells (MNCs), of the paraventricular and supraoptic nuclei of the hypothalamus, secrete the hormones vasopressin and oxytocin. As a result, they have an essential role in fundamental physiological responses including regulation of blood volume and fluid homeostasis. C-type natriuretic peptide (CNP) is present at high levels in the hypothalamus. Although CNP is known to decrease hormone secretion from MNCs, no studies have examined the role of the natriuretic peptide C receptor (NPR-C) in these neurons. In this study, whole cell recordings from acutely isolated MNCs, and MNCs in a coronal slice preparation, show that CNP (2 × 10−8M) and the selective NPR-C agonist, cANF (2 × 10−8M), significantly inhibit L-type Ca2+current ( ICa(L)) by ∼50%. This effect on ICa(L)is mimicked by dialyzing a Gi-activator peptide (10−7M) into these cells, implicating a role for the inhibitory G protein, Gi. These NPR-C–mediated effects were specific to ICa(L). T-type Ca2+channels were unaffected by CNP. Current-clamp experiments revealed the ability of CNP, acting via the NPR-C receptor, to decrease (∼25%) the number of action potentials elicited during a 500 ms depolarizing stimulus. Analysis of action potential duration revealed that CNP and cANF significantly decreased 50% repolarization time (APD50) in MNCs. In summary, our findings show that CNP has a potent and selective inhibitory effect on ICa(L)and on excitability in MNCs that is mediated by the NPR-C receptor. These data represent the first electrophysiological evidence of a functional role for the NPR-C receptor in the mammalian hypothalamus.
Impaired Cl−Extrusion in Layer V Pyramidal Neurons of Chronically Injured Epileptogenic Neocortex
Authors: Jin Xiaoming , Huguenard John R. , Prince David A.
Published: March 2005

In the mature brain, the K+/Cl−cotransporter KCC2 is important in maintaining low [Cl−]i, resulting in hyperpolarizing GABA responses. Decreases in KCC2 after neuronal injuries result in increases in [Cl−]iand enhanced neuronal excitability due to depolarizing GABA responses. We used the gramicidin perforated-patch technique to measure ECl(∼ EGABA) in layer V pyramidal neurons in slices of partially isolated sensorimotor cortex of adult rats to explore the potential functional consequence of KCC2 downregulation in chronically injured cortex. EGABAwas measured by recording currents evoked with brief GABA puffs at various membrane potentials. There was no significant difference in EClbetween neurons in control and undercut animals (–71.2 ± 2.6 and –71.8 ± 2.8 mV, respectively). However, when loaded with Cl−by applying muscimol puffs at 0.2 Hz for 60 s, neurons in the undercut cortex had a significantly shorter time constant for the positive shift in EClduring the Cl−loading phase (4.3 ± 0.5 s for control and 2.2 ± 0.4 s for undercut, P < 0.01). The positive shift in ECl3 s after the beginning of Cl−loading was also significantly larger in the undercut group than in the control, indicating that neurons in undercut cortex were less effective in maintaining low [Cl−]iduring repetitive activation of GABAAreceptors. Application of furosemide eliminated the difference between the control and undercut groups for both of these measures of [Cl−]iregulation. The results suggest an impairment in Cl−extrusion resulting from decreased KCC2 expression that may reduce the strength of GABAergic inhibition and contribute to epileptogenesis.
Object Motion Computation for the Initiation of Smooth Pursuit Eye Movements in Humans
Authors: Wallace Julian M. , Stone Leland S. , Masson Guillaume S.
Published: March 2005

Pursuing an object with smooth eye movements requires an accurate estimate of its two-dimensional (2D) trajectory. This 2D motion computation requires that different local motion measurements are extracted and combined to recover the global object-motion direction and speed. Several combination rules have been proposed such as vector averaging (VA), intersection of constraints (IOC), or 2D feature tracking (2DFT). To examine this computation, we investigated the time course of smooth pursuit eye movements driven by simple objects of different shapes. For type II diamond (where the direction of true object motion is dramatically different from the vector average of the 1-dimensional edge motions, i.e., VA ≠ IOC = 2DFT), the ocular tracking is initiated in the vector average direction. Over a period of less than 300 ms, the eye-tracking direction converges on the true object motion. The reduction of the tracking error starts before the closing of the oculomotor loop. For type I diamonds (where the direction of true object motion is identical to the vector average direction, i.e., VA = IOC = 2DFT), there is no such bias. We quantified this effect by calculating the direction error between responses to types I and II and measuring its maximum value and time constant. At low contrast and high speeds, the initial bias in tracking direction is larger and takes longer to converge onto the actual object-motion direction. This effect is attenuated with the introduction of more 2D information to the extent that it was totally obliterated with a texture-filled type II diamond. These results suggest a flexible 2D computation for motion integration, which combines all available one-dimensional (edge) and 2D (feature) motion information to refine the estimate of object-motion direction over time.
Long-Lasting Modulation by Stimulus Context in Primate Auditory Cortex
Authors: Bartlett Edward L. , Wang Xiaoqin
Published: March 2005

A sound embedded in an acoustic stream cannot be unambiguously segmented and identified without reference to its stimulus context. To understand the role of stimulus context in cortical processing, we investigated the responses of auditory cortical neurons to 2-sound sequences in awake marmosets, with a focus on stimulus properties other than carrier frequency. Both suppressive and facilitatory modulations of cortical responses were observed by using combinations of modulated tone and noise stimuli. The main findings are as follows. 1) Preceding stimuli could suppress or facilitate responses to succeeding stimuli for durations >1 s. These long-lasting effects were dependent on the duration, sound level, and modulation parameters of the preceding stimulus, in addition to the carrier frequency. They occurred regardless of whether the 2 stimuli were separated by a silent interval. 2) Suppression was often tuned such that preceding stimuli whose parameters were similar to succeeding stimuli produced the strongest suppression. However, the responses of many units could be suppressed, although often weaker, even when the 2 stimuli were dissimilar. In some cases, only a dissimilar preceding stimulus produced suppression in the responses to the succeeding stimulus. 3) In contrast to suppression, facilitation of responses to succeeding stimuli by the preceding stimulus was usually strongest when the 2 stimuli were dissimilar. 4) There was no clear correlation between the firing rate evoked by the preceding stimulus and the change in the firing rate evoked by the succeeding stimulus, indicating that the observed suppression was not simply a result of habituation or spike adaptation. These results demonstrate that persistent modulations of the responses of an auditory cortical neuron to a given stimulus can be induced by preceding stimuli. Decreases or increases of responses to the succeeding stimuli are dependent on the spectral, temporal, and intensity properties of the preceding stimulus. This indicates that cortical auditory responses to a sound are not static, but instead depend on the stimulus context in a stimulus-specific manner. The long-lasting impact of stimulus context and the prevalence of facilitation suggest that such cortical response properties are important for auditory processing beyond forward masking, such as for auditory streaming and segregation.
X- and Y-chromosome specific variants of the amelogenin gene allow sex determination in sheep (Ovis aries) and European red deer (Cervus elaphus)
Authors: Pfeiffer I , Brenig B
Published: March 2005

Background

Simple and precise methods for sex determination in animals are a pre-requisite for a number of applications in animal production and forensics. However, some of the existing methods depend only on the detection of Y-chromosome specific sequences. Therefore, the abscence of a signal does not necessarily mean that the sample is of female origin, because experimental errors can also lead to negative results. Thus, the detection of Y- and X-chromosome specific sequences is advantageous.

Results

A novel method for sex identification in mammals (sheep, Ovis aries and European red deer, Cervus elaphus) is described, using a polymerase chain reaction (PCR) and sequencing of a part of the amelogenin gene. A partial sequence of the amelogenin gene of sheep and red deer was obtained, which exists on both X and Y chromosomes with a deletion region on the Y chromosome. With a specific pair of primers a DNA fragment of different length between the male and female mammal was amplified.

Conclusion

PCR amplification using the amelogenin gene primers is useful in sex identification of samples from sheep and red deer and can be applied to DNA analysis of micro samples with small amounts of DNA such as hair roots as well as bones or embryo biopsies.
Efficacy of acupuncture for cocaine dependence: a systematic review & meta-analysis
Authors: Mills Edward J , Wu Ping , Gagnier Joel , Ebbert Jon O
Published: March 2005

Background

Acupuncture is a commonly used treatment option for the treatment of addictions such as alcohol, nicotine and drug dependence. We systematically reviewed and meta-analyzed the randomized controlled trials of acupuncture for the treatment of cocaine addiction.

Methods

Two reviewers independently searched 10 databases. Unpublished studies were sought using Clinicaltrials.gov, the UK National Research Register and contacting content experts. Eligible studies enrolled patients with the diagnosis of cocaine dependence of any duration or severity randomly allocated to either acupuncture or sham or other control. We excluded studies of acupuncture methods and trials enrolling patients with polysubstance use or dependence. We abstracted data on study methodology and outcomes. We pooled the studies providing biochemical confirmation of cocaine abstinence.

Results

Nine studies enrolling 1747 participants met inclusion criteria; 7 provided details for biochemical confirmation of cocaine abstinence. On average, trials lost 50% of enrolled participants (range 0–63%). The pooled odds ratio estimating the effect of acupuncture on cocaine abstinence at the last reported time-point was 0.76 (95% CI, 0.45 to 1.27, P = 0.30, I2 = 30%, HeterogeneityP = 0.19).

Conclusion

This systematic review and meta-analysis does not support the use of acupuncture for the treatment of cocaine dependence. However, most trials were hampered by large loss to follow up and the strength of the inference is consequently weakened.
Influence of immunomagnetic enrichment on gene expression of tumor cells
Authors: Woelfle Ute , Breit Elisabeth , Pantel Klaus
Published: March 2005

Background

Metastasis is the leading cause of cancer-related death. Bone marrow (BM) is a frequent site for the settlement of disseminated tumor cells which occurs years before overt metastases signal incurability.

Methods

Here we describe a new method to assess the initial stage of metastasis development in cancer patients. By immunomagnetic selection with HER2/neu and EpCAM as catcher antigens single disseminated tumor cells can be enriched from BM samples. To examine whether the immunomagnetic enrichment technique may change gene expression in the selected tumor cells, we performed differential expression profiling with the breast cancer cell lines MCF-7 and BT474 as models. The profiles were performed using 1.2 Cancer Arrays (Clontech) containing 1176 cDNAs that can be grouped into different functional categories, such as signal transduction, cell cycle, adhesion, cytoskeleton plasticity, growth factors and others.

Results

The reproducibility of the gene expression profiling between duplicate cDNA-array experiments was assessed by two independent experiments with MCF-7 breast cancer cells. Scatter blot analysis revealed a good reproducibility of the cDNA array analysis (i.e. less than 10% difference in the gene expression between the arrays). Subsequent comparative cDNA-array analyses of immunobead-selected and unselected MCF-7 and BT474 cancer cells indicated that the antibody incubation during the immunomagnetic selection procedure did not considerably alter the gene expression profile.

Conclusion

The described method offers an excellent tool for the enrichment of micrometastatic tumor cells in BM without largely changing the gene expression pattern of these cells.
The homeodomain protein PAL-1 specifies a lineage-specific regulatory network in theC. elegansembryo
Authors: Baugh L. Ryan , Hill Andrew A. , Claggett Julia M. , Hill-Harfe Kate , Wen Joanne C. , Slonim Donna K. , Brown Eugene L. , Hunter Craig P.
Published: March 2005

Maternal and zygotic activities of the homeodomain protein PAL-1 specify the identity and maintain the development of the multipotent C blastomere lineage in the C. elegans embryo. To identify PAL-1 regulatory target genes, we used microarrays to compare transcript abundance in wild-type embryos with mutant embryos lacking a C blastomere and to mutant embryos with extra C blastomeres. pal-1-dependent C-lineage expression was verified for select candidate target genes by reporter gene analysis, though many of the target genes are expressed in additional lineages as well. The set of validated target genes includes 12 transcription factors, an uncharacterized wingless ligand and five uncharacterized genes. Phenotypic analysis demonstrates that the identified PAL-1 target genes affect specification, differentiation and morphogenesis of C-lineage cells. In particular, we show that cell fate-specific genes (or tissue identity genes)and a posterior HOX gene are activated in lineage-specific fashion. Transcription of targets is initiated in four temporal phases, which together with their spatial expression patterns leads to a model of the regulatory network specified by PAL-1.
Heat of Formation for the Methylenimmonium Cation by Photoionization Mass Spectrometry
Authors: Harvey Zoë A. , Traeger John C.
Published: March 2005

Photoionization mass spectrometry has been used to measure the CH2NH2+ appearance energies for six primary amines, resulting in a 298K heat of formation of 749.5 ± 1.3 kJ mol−1 for the methylenimmonium cation. An absolute proton affinity of 868.8 ± 2.5 kJ mol−1 is derived for methylenimine. Based on experimental data for ethylenediamine, the 298 K heat of formation for the aminomethyl radical is found to be 153.6 ± 1.7 kJ mol−1. These results are supported by high-level ab initio calculations.
Water Dimer Proton Affinity from the Kinetic Method: Dissociation Energy of the Water Dimer
Authors: Goebbert Daniel J. , Wenthold Paul G.
Published: March 2005

The proton affinity of water dimer was measured, using the kinetic method with nitrile reference bases, to be 808±6 kJ mol−1. The difference between the measured value and the proton affinity of a single water molecule (690±4 kJ mol−1) reflects the difference in solvation energy for two neutral water molecules (the hydrogen bond energy of water dimer), and the energy for solvation of hydronium cation and water. Using the measured proton affinity of the dimer along with ancillary data yields an experimental value of the hydrogen bond energy of neutral water dimer, 18±9 kJ mol−1, in good agreement with previous experimental and theoretical values. The proton affinity of the dimer measured by using alcohol references is ca 100 kJ mol−1 too low, likely because the structure of the protonated cluster is not well-suited for kinetic method measurements. These results highlight the importance of choosing reference bases that form cluster ions consisting of a proton bound complex between the water dimer and the reference base.
Energy and Stability of Protonated Ketenes: Inductive and Resonance Effects
Authors: Ervasti Henri K. , Burgers Peter C. , Ruttink Paul J.A.
Published: March 2005

The proton affinities ( PA) of electronegatively-substituted ketenes RCH = C = O (R = H, CH3, NH2, OH and F) at various sites have been assessed by CBS-QB3 calculations. The most favorable protonation site was found to be the CH carbon atom to produce the acylium ions RCH2C+ = O. The PA values, relative to that of CH2 = C = O, can be interpreted in terms of destabilizing effects of the R group in RCH = C = O [ J. Am. Chem. Soc. 113, 6021 (1991)] and by positive or negative inductive effects of R in RCH2C+ = O. For HOCH = C = O the two destabilizing effects are of similar magnitude and this rationalizes that its PA (823 kJ mol−1) is virtually the same as that for CH2 = C = O (820 kJ mol−1). For all ketenes (except for R = H), protonation leads to significant activation of the C=C bond. In the extreme case, protonation of H2NCH = C = O at CH ( PA = 917 kJ mol−1) leads to the weakly bonded complex H2NCH2+••••C = O with a C–C length of 2.92 Å and which only needs 15 kJ mol−1 to dissociate to H2NCH2+ + CO. In fact, the covalently-bonded species, H2NCH2C+ = O, does not exist, the most stable configuration being CH2 = N(H)–H+••••C = O. When NH4+ ( PA[NH3] = 854 kJ mol−1) approaches the NH2 group of H2NCH = C = O ( PA at N = 845 kJ mol−1), the stable hydrogen-bridged cation H3N–H+••••NH2–CH = C = O is produced. The NH4+ group can move over to the CH group or it can attack the CH group directly. After passing a transition state, dissociation follows to NH3 + CH3NH3+ + CO. For neutral methylketene, CBS-QB3 calculates a heat of formation of −63 kJ mol−1, in good agreement with an experimental value (–67 ± 5 kJ mol−1) but not with another experimental number (–95 ± 5 kJ mol−1) and these matters are discussed. Suggestions for further experimental work are proposed to address this discrepancy.
Gas-Phase Kinetic Measurements of the Ligation of Ni+, Cu+, Ni(Pyrrole)1,2+ and Cu(Pyrrole)1,2+ with CO2, D2O, NH3 and NO
Authors: Jarvis Michael J.Y. , Blagojevic Voislav , Koyanagi Gregory K. , Bohme Diethard K.
Published: March 2005

The rate and equilibrium kinetics of the reactions of the biologically important metal species M+, M+(pyrrole) and M+(pyrrole)2 (M = Ni, Cu) have been investigated with the biological gases CO2, D2O, NH3 and NO in the gas phase at 295 ± 2 K in helium buffer-gas at a pressure of 0.35 ± 0.01 Torr. The measurements were taken with an Inductively Coupled Plasma/Selected-Ion Flow Tube (ICP/SIFT) tandem mass spectrometer. Only ligation was observed for the reactions of bare Ni+ and Cu+ with CO2, D2O and NH3 with rates consistent with the known strengths of the resulting ligand–metal bonds. Both metal cations appeared to be oxidized and produce N2O in interesting reactions that are second order in NO. One pyrrole ligand was observed to increase the rate of ligation by as much as a factor of 100 and to switch off the oxidation with NO. Equilibrium was achieved for the ligation of CO2, D2O and NO to both Ni+(pyrrole) and Cu+(pyrrole), and so it was possible to determine absolute values for the standard free energies of ligation. No ligand substitution was observed with M+(pyrrole). M+(pyrrole)2 was observed to be generally unreactive towards the small molecules investigated: a notable exception is ammonia. Very fast ligand substitution reactions were observed for reactions of M+(pyrrole)2 with NH3.
Isolation of Isomers Based on Hydrogen/Deuterium Exchange in the Gas Phase
Authors: Mazurek Ulf , McFarland Melinda A. , Marshall Alan G. , Lifshitz Chava
Published: March 2005

A method to isolate isomers in a Fourier transform ion cyclotron resonance mass spectrometer on the basis of their different hydrogen/deuterium exchange rates has been developed and applied to the protonated serine octamer cluster. Isolation allows interrogation of each isomer by infrared multi-photon dissociation to determine any differences in the building blocks that form these clusters. The experimental results strongly support previous assignments of an all-zwitterion structure to the slower-exchanging isomer and an all-neutral structure to its faster-exchanging counterpart.
Unimolecuclar Fragmentation and Isomerization of Gaseous Arsanyl Cations Y—C6H4As+X (X=F, Cl, Br, I). The Role of Non-Classical Nido Structures
Authors: Kirchhoff Dirk , Grützmacher Hans-Friedrich , Grützmacher Hansjörg
Published: March 2005

The halogeno-(4-halogenophenyl)arsanyl cations Y–C6H4As+X (X=F, Cl, Br, I) are abundant in the 70 eV EI mass spectra of dihalogeno-(4-halogenophenyl)arsanes Y–C6H4AsX2. This has been used to study the unimolecular reactions of ions Y–C6H4As+X by techniques of tandem mass spectrometry with respect to a possible rearrangement to nido-isomers, ñ4-(XYC6H4)As+, in which the As+ is capping a dihalogenobenzene moiety, YC6H4AX. The mass analyzed ion kinetic energy (MIKE) spectra of Y–C6H4As+X, 1a+–3a+ and 5a+ (X, Y=F, Cl, Br, see Scheme 2), display broad and even dish-topped peaks for the loss of HX and HY, respectively, indicating a large kinetic energy release ( KER) during these reactions and the presence of a large reverse activation energy. The mean value of the KER, < T>, is specific for the type of the halogen substituent but independent of its original position and is identical to < T> found for the loss of HX or HY from metastable halogeno–phenylarsanyl cations, C6H5As−X or C6H4As+Y. These results give strong evidence for a positional change of X and Y in Y–C6H4As+X before fragmentation, plausibly via intermediate ñ4-(XYC6H4)As+. However, the relative intensities of the signals for loss of HX and HY are different in the MIKE spectra of isomeric arsanyl cations and the spectra of the isomers obtained by collision-induced decomposition show that the metastable arsanyl cations represent a mixture of isomers with the original arsanyl cation prevailing. Clearly, interchange of halogen substituents in Y–C6H4XAs+ is slow compared with fragmentation and the intermediate nido-isomer, ñ4-(XYC6H4)As+, is separated from the isomers of the classical structure of a halogeno-(halogenophenyl)arsanyl cation by substantial activation barriers. Therefore, in the case of 4a+ and 6a+ (X, Y=Cl, I), any rearrangement is obstructed by the facile loss of the weakly bonded I substituent. This reaction model was verified by theoretical calculations of relevant stationary points of the minimum energy reaction pathways ( MERP) of fragmentation and rearrangement at the level UBHLYP/6-311+g(2d,p)//UBHLYP/6-31+g(d). In particular, the calculations show that the nido isomers, ñ4-(XYC6H4)As+, are stable species but higher in energy than their “classical” isomers.
The Unimolecular Reactions of Ionized Methylacetamides
Authors: Jensen Lars Bo , Hammerum Steen
Published: March 2005

The gas-phase decarbonylation of the N-methyl- and N,N-dimethylacetamide radical cations gives rise to the α-distonic isomers of the dimethylamine and trimethylamine molecular ions by transfer of the acetyl methyl to nitrogen in two steps: H transfer and CH2 transfer. Complete exchange af all carbon-bonded hydrogen atoms precedes loss of acetyl radicals or of ketene from the metastable amide molecular ions. The reactions are examined with deuterium labeling and with composite ab initio methods of the G3 family.
The Formation and Heats of Formation of Simple α-Distonic Ions
Authors: Jensen Lars Bo , Hammerum Steen
Published: March 2005

Several methods for the preparation of α-distonic radical cations by unimolecular fragmentation in the gas phase have been examined, but generally applicable and satisfactory methods were not found. One commonly encountered problem is the contamination of the product ion beam by isotopic contributions from ions whose nominal mass is one unit lower (often formed by simple cleavage of the precursor ion). A novel α-distonic ion, (CH3)2NHCH2+•, was discovered and characterized. Composite ab initio methods of the G3 and CBS families were used to determine the heats of formation of the molecular ions and the α-distonic isomers of simple alcohols, ethers and amines with up to four carbon atoms. The α-distonic isomers are the lower energy species only for ionized alcohols and primary amines.
ZIRLO™ — An Alloy Development Success
Authors: Sabol GP
Published: March 2005

Significant data and milestones in the development of the ZIRLO alloy for PWR applications are reviewed. From humble beginnings as an R&D program, an approach to improving the corrosion resistance of zirconium-based alloys was developed. The corrosion resistance of dilute alloys is controlled by the microstructure, and both solid solution and precipitate effects impact corrosion performance. Several transition metals are beneficial for corrosion at low concentrations, but the most favorable alloy system is zirconium-niobium, because it offers flexibility in processing options. Strength of the binary alloys can be improved by additions of tin, which, in combination with low levels of iron, provide corrosion resistance in lithium hydroxide solutions. Numerous experimental ingots, thermo-mechanical processing routes, corrosion tests, and materials characterizations were performed along the path to the final alloy composition. The resulting material, ZIRLO, has proven itself as a successful alloy for PWR fuel cladding and structural applications.
The Supreme Court versus Peyote: Consciousness Alteration, Cultural Psychiatry and the Dilemma of Contemporary Subcultures
Authors: Calabrese Joseph D.
Published: March 2005

The Native American Church is examined as an illustrative example in the political anthropology of consciousness. Specific attention is paid to the Supreme Court's ignoring of accepted research on this tradition and its sacrament, Peyote, in the case of Employment Division of Oregon v. Smith. An anthropological reaction to the Smith decision is constructed, focusing on ethnographic findings regarding Peyote that contradict the Supreme Court's ethnocentric assumptions. This paper argues that Peyote's Schedule I status is not supported by the ethnographic findings. Peyote, as used in the Native American Church, is recognized as safe and therapeutic. It is also argued that the Supreme Court's rationale for denying Peyotist religious freedom is not supported by the ethnographic findings nor by legal precedent. Not only is the Native American's right to use Peyote a matter of freedom of religion, it also involves other rights such as the right to raise one's children in one's own culture and the right to be treated using a culturally relevant therapeutic modality.
“We are the border”: identity, exchange, and the state along the Bénin‐Nigeria border
Authors: Flynn Donna K.
Published: March 2005

Border residents in the Yoruba‐speaking Shabe region along the Bénin‐Nigeria international border have relied on transborder trade as a source of income since the border was first established by French and British colonial governments. Over the past 20 years, however, economic change in the region has significantly reduced transborder traffic and its accompanying income‐earning opportunities for local borderlanders. Border residents have subsequently forged a strong sense of “border identity.” This identity emerges primarily in contexts of transborder exchange and is based both on residential claims to the region and on borderlanders' perceived rights to participation in transborder trade.
The poetics and politics of recognition: diasporan Sikhs in pluralist polities
Authors: Dusenbery Verne A.
Published: March 2005

In this article I explore the intersection of nationalist and multiculturalist discourses in the contemporary world. I contrast the experiences of Canadian Sikhs and Singaporean Sikhs to suggest ways in which the nationalist and multiculturalist projects of two pluralistic nation‐states (Canada and Singapore) have affected local political fortunes of the Sikhs, a small but visible ethnocultural group with its own global nationalist aspirations. I attribute the different fortunes of Sikhs in gaining the recognition of the state, in part, to differences in state ideologies, policies, and practices of nation building and ethnic management in corporatist Singapore and quasi‐liberal Canada. In this analysis I highlight the challenges and costs of playing the “politics of recognition” at the intersection of pluralist polities and global ethnoscapes and suggest how ethnographers might fruitfully engage the poetics and politics of sameness and difference.
Gift or commodity: what changes hands in the U.S. garage sale?
Authors: Herrmann Gretchen M.
Published: March 2005

The U.S. garage sale incorporates elements of both gift and commodity exchange in a dynamic tension, one that complicates traditional characterizations of gift and commodity as oppositional and mutually exclusive. Despite its apparently marketlike mechanisms, much of garage sale exchange also partakes of the character of gift giving. The elasticity in pricing in this home‐based exchange allows sellers to take social relations into account, so that objects that change hands become hybrid varieties of “inalienable commodities.”
Occult economies and the violence of abstraction: notes from the South African postcolony
Authors: Comaroff Jean , Comaroff John L.
Published: March 2005

Postcolonial South Africa, like other postrevolutionary societies, appears to have witnessed a dramatic rise in occult economies: in the deployment, real or imagined, of magical means for material ends. These embrace a wide range of phenomena, from "ritual murder," the sale of body parts, and the putative production of zombies to pyramid schemes and other financial scams. And they have led, in many places, to violent reactions against people accused of illicit accumulation. In the struggles that have ensued, the major lines of opposition have been not race or class but generation—mediated by gender. Why is all this occurring with such intensity, right now? An answer to the question, and to the more general problem of making sense of the enchantments of modernity, is sought in the encounter of rural South Africa with the contradictory effects of millennial capitalism and the culture of neoliberalism. This encounter, goes the argument, brings "the global" and "the local"— treated here as analytic constructs rather than explanatory terms or empirical realities—into a dialectical interplay. It also has implications for the practice of anthropology, challenging us to do ethnography on an "awkward" scale, on planes that transect the here and now, then and there,
Villages dammed, villages repossessed: a memorial movement in northwest China
Authors: Jing Jun
Published: March 2005

In this article, I employ the concept of repossession to analyze the politics of memory in the rural county of Yongjing, northwest China. I focus on an innovative social movement that works toward community recovery from the devastating impacts of forced resettlement and farmland destruction. I suggest why this movement should be considered a social process by which memories of trauma were transformed into a political discourse that holds a powerful state bureaucracy accountable for a multiplicity of injuries inflicted in the name of economic development. The concept of repossession, strictly defined within the context of collective actions, refers to the attempts of displaced and disenfranchised peasants to regain a politically silenced voice of resentment, reestablish a material basis of village life, and reconstruct a ruined landscape of popular religion
Alguito para ganar(a little something to earn): profits and losses in peasant economies
Authors: Mayer Enrique , Glave Manuel
Published: March 2005

We explore various ways in which small‐scale peasants in the highlands of Peru conceptualize the everyday concept of profit in the contemporary context of neoliberalism. Through a process of approximations, we use the results of a survey of potato fields in two comparable valleys in Peru to clarify the differences between a strict business accounting procedure to establish profits or losses and the procedure that peasants use to evaluate the profitability of cash crops. We suggest that peasants evaluate profits or losses of cash crops in terms of a simple cash‐out and cash‐in flow. We indicate that this kind of calculus carries an implicit subsidy that permits market participation but provides little or no long‐run benefit under prevailing productivity conditions and price levels. We also look at how farmers evaluate the status of their subsistence crops by showing that they ignore important cash expenses that are necessary to produce them. Finally, we describe accounting procedures characteristic of Andean peasants to understand how they monitor resource flows in their household‐based farms. Analysis of the data leads us to question the "subsistence first" model of peasant economies and to posit an interdependent relationship between subsistence and commercial sectors in which money plays an important but perverse role as it cycles through the market and the household.
Using Simulation Techniques to Estimate Management Parameters on Snake River Steelhead: Declines in Productivity Make Rebuilding Difficult
Authors: Yuen Henry , Sharma Rishi
Published: March 2005

We collected adult and juvenile spawner recruit data on wild summer steelhead Oncorhynchus mykiss for the Snake River and estimated parameters for fisheries management by partitioning the data into predam and postdam periods and fitting the Ricker and Beverton–Holt models to those time series. The results showed a decline in productivity irrespective of the model chosen and the way in which the pre- and postdam periods were defined. However, the data were noisy and the confidence bounds on parameter estimates were fairly large. To reconcile the different management goals derived from the different data sources (adult or juvenile data) or model choice (Ricker or Beverton–Holt), we used simulation techniques and Bayesian algorithms. The combined approach suggests a recovery management goal (i.e., spawning stock associated with the maximum sustainable yield) of 60,000 steelhead above Lower Granite Dam. At current smolt-to-adult survival rates, the data indicate optimal escapement of between 20,000 and 27,000 adults. We note that Snake River steelhead stocks cannot be managed for recovery escapement levels given current estimates of smolt-to-adult survival rates, and we discuss alternatives for present-day management and rebuilding over time.
Range and Movement of Resident Holdover and Hatchery Brown Trout Tagged with Radio Transmitters in the Farmington River, Connecticut
Authors: Popoff Nicholas D. , Neumann Robert M.
Published: March 2005

The 5.8-km West Branch Farmington River Trout Management Area (TMA) is one of Connecticut's premier catch-and-release fisheries for brown trout Salmo trutta. However, little is known about the behavior of brown trout in this system and to what extent brown trout emigrate from the TMA. The objectives of this study were to determine the movement, range, and emigration of resident holdover and newly stocked brown trout tagged with radio transmitters in the TMA. Transmitters were implanted into 22 first-year (mean total length = 314 mm) and 25 second-year (mean total length = 432 mm) holdover brown trout. Twenty catchable-size (mean total length = 290 mm) brown trout were also implanted with transmitters and released into the TMA. The mean range (distance between the extreme upstream and downstream locations) was greater for second-year holdover brown trout than for first-year holdover brown trout, and it was greater in fall than in winter. The movement (distance moved between successive locations) of holdover brown trout was greater in fall than in winter. Movement of first-year holdover brown trout was significantly related to discharge, water temperature, and the number of days between successive locations. Newly stocked brown trout exhibited the two largest ranges (5.3 and 4.7 km). The range of newly stocked brown trout was not different between seasons, but movement was greater in spring than in summer. Through 16 weeks poststocking, there was no discernable difference in the percentage of stocked brown trout dispersing in a predominantly upstream or downstream direction. Mean dispersal distances from the stocking location were 0.5 and 0.9 km at 2 and 12 weeks poststocking, respectively. Movement of newly stocked brown trout was positively related to discharge and negatively related to water temperature. A known 6% (4 of 67) of the tagged brown trout emigrated from the TMA, but up to 21% (14 of 67) of tagged fish could have left the study area if all missing fish were emigrants.
Early retirement due to occupational injury: Who is at risk?
Authors: Pransky Glenn S. , Benjamin Katy L. , Savageau Judith A.
Published: March 2005

Background

As the workforce is rapidly ageing, research on the consequences of occupational injuries in older workers is becoming more important. One adverse outcome unique to older workers, early retirement, has significant negative social and economic consequences for workers and employers. Although linked to poor worker health, the roles of workplace factors and occupational injury have not been well‐defined.

Method

Changes in retirement plans attributed to an occupational injury were studied in a population‐based sample of 1,449 New Hampshire workers aged ≤55, using a mailed survey. Questions addressed pre‐and post‐injury health, job satisfaction, work capacity, nature and severity of injury, medical care, employer response, work status, pain, and financial problems.

Result

Eleven percent planned to retire earlier due to their work injury, and their outcomes were significantly worse. In a multivariate model, pre‐injury dissatisfaction with the job and with medical care, and poor physical and mental health status were related to intent to retire early.

Conclusion

These factors may represent opportunities for early identification and intervention with individuals at high risk for poor post‐injury outcomes. Longitudinal studies are needed to confirm the importance of these preliminary findings. Am. J. Ind. Med. 47:285–295 2005. © 2005 Wiley‐Liss, Inc.
Grafting of cotton with β‐cyclodextrin via poly(carboxylic acid)
Authors: Voncina B. , Le Marechal A. Majcen
Published: March 2005

Cyclodextrins are cyclic oligosaccharides. Cyclodextrin molecules can form inclusion complexes with a large number of organic molecules. The properties of cyclodextrins enable them to be used in a variety of different textile applications. Cyclodextrins can act as auxiliaries in washing and dyeing processes, and they can also be fixed onto different fiber surfaces. Because of the complexing abilities of cyclodextrins, textiles with new functional properties can be prepared. Poly(carboxylic acid)s such as 1,2,3,4‐butane tetracarboxylic acid (BTCA) are well‐known non‐formaldehyde crosslinking reagents. BTCA has four carboxylic acid groups, which can react with hydroxyl groups of cellulose and form stable ester bonds. We crosslinked β‐cyclodextrin molecules on hydroxyl groups of cellulose via BTCA. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1323–1328, 2005
Protonation Sites of Indoles and Benzoylindoles
Authors: Hoyuelos Francisco J. , García Begoña , Ibeas Saturnino , Muñoz María S. , Navarro Ana M. , Peñacoba Indalecio , Leal José M.
Published: March 2005

Indomethacine (1) and acemethacine (2) contain the substituents ‐OCH3, ‐CH2COOH, ‐CH2COOCH2COOH, C‐indole and O‐benzoyl, which are susceptible to protonation in highly acidic media. To determine the protonation sites and the substituent effects reliably, the dissociation constants of the set of structurally related compounds 1‐benzoyl‐3‐methylindole (3), 1‐benzoyl‐5‐methoxyindole (4), 1‐benzoylindole (5), 5‐methoxy‐2‐methylindole (6), (2‐methylindol‐3‐yl)acetic acid (7) and (5‐methoxy‐2‐methylindol‐3‐yl)acetic acid (8) were investigated in concentrated perchloric acid. The UV/Visible spectral curves were studied by the Hammett, Bunnett–Olsen and excess acidity methods, and the observed medium effects of 1 to 5 were analysed by the vector analysis and excess acidity methods. Acemethacine (2) displays two acid–base equilibria with pK(i) = –2.3 and pK = –4.2, corresponding to the ester and amide groups. The benzoylindoles 1, 3, 4 and 5 each show a single amide equilibrium pK ≈ –4.2, independently of the substituent. Indoles 6–8 are stronger bases than benzoylindoles. Substitution of the indole H (NH) by the benzoyl group strongly reduces the N basicity, and increases the O basicity with protonation of the CO group. The solvation parameters, m* = 0.70 for benzoylindoles and m* = 1.3 for indoles, reveal greater charge location and less solvation requirements in the latter. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Olefinic Isothiocyanates and Iminodithiocarbonates from the Liverwort Corsinia coriandrina
Authors: von Reuß Stephan H. , König Wilfried A.
Published: March 2005

The chemical investigation of the liverwort Corsinia coriandrina, Corsiniaceae, resulted in the isolation, structure elucidation and synthesis of four sulfur‐ and nitrogen‐containing compounds. The coriandrins were identified as (Z)‐ and (E)‐2‐(4‐methoxyphenyl)ethenyl isothiocyanates, while the O‐methyltridentatols contain the corresponding (Z)‐ and (E)‐S,S‐dimethyl 2‐(4‐methoxyphenyl)ethenyliminodithiocarbonate structures. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Design and Evaluation of Inclusion Resolutions, Based on Readily Available Host Compounds
Authors: Müller Simona , Afraz Marcel Cyrus , de Gelder René , Ariaans Gerry J. A. , Kaptein Bernard , Broxterman Quirinus B. , Bruggink Alle
Published: March 2005

Resolution of enantiomers through selective crystallisation of diastereomeric inclusion compounds can extend the scope of traditional racemate resolution beyond salt forming compounds. To assess the practical value of this approach the literature was carefully screened and promising results were checked. Also an extensive range of new inclusion hosts suitable for resolution processes, derived from simple hydroxy‐ and amino acids were prepared and tested. Several techniques, including the Dutch Resolution approach utilizing mixtures of resolving agents, were applied. Over 70 potential resolving agents were tested in combinations with 34 racemates (over 100 racemates if literature results are included). Reproducibility of literature results was found to be problematic. Also the number of successful new resolutions found was very limited: only two efficient resolutions out of 1200 combinations of racemate and resolving agent tested in over 10.000 experiments! Crystal studies of representative combinations of resolving agents and inclusion compounds revealed some of the causes for the low rate of success in inclusion resolution. Compared to diastereomeric salts, the absence of strong electrostatic interactions substantially reduces the probability of forming crystals including both components. Molecular structure features allowing formation of intricate intramolecular and intermolecular H‐bond networks were found to be responsible for inclusion crystal formation, and for the quality of the ensuing resolution through selective diastereomer crystallisation, in the successful cases. Whereas diastereomeric salt resolution continues to be of scientific and industrial interest, inclusion resolution should be viewed as of very limited scope; useful in specific instances, but lacking the wide applicability of classical resolution. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Efficient Photosensitized Splitting of Thymine Dimer by a Covalently Linked Tryptophan in Solvents of High Polarity
Authors: Song Qin‐Hua , Tang Wen‐Jian , Hei Xiao‐Ming , Wang Hong‐Bo , Guo Qing‐Xiang , Yu Shu‐Qin
Published: March 2005

Tryptophan‐thymine dimer model compounds used to mimic the repair reaction of DNA photolyase have been synthesized. The photosensitized cleavage of the dimer by the covalently linked tryptophan is strongly solvent‐dependent with the reaction rates increasing in increasingly polar solvents, for example, the quantum yield Φ = 0.004 in THF/hexane (5:95) and 0.093 in water. The fluorescence of the tryptophan residue is quenched by the dimer moiety by electron transfer from the excited tryptophan to the dimer. Fluorescence‐quenching studies indicated that the electron transfer was efficient in polar solvents. The splitting efficiency of the dimer radical anion within the tryptophan·+–dimer·– species is also remarkably solvent‐dependent and increases with the polarity of the solvents. The back‐electron‐transfer reaction in the charge‐separated species, which competes with cleavage, was suppressed in polar solvents. These results are in contrast to those of earlier solvent‐dependent studies of indole‐dimer systems, but they can be rationalized in terms of the differences in the distances between the chromophore unit and the attached dimer. The pH‐dependent measurements of the splitting reaction and the deuterium isotope effect showed that the tryptophan radical cation within the charge‐separated species does not deprotonate prior to the cleavage of the dimer radical anion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)