bluuebunny/crossref_metadata_2025 huggingface dataset:
US Approaches to Multilateral Security and Economic Organizations in the Asia‐Pacific
Authors: Cossa Ralph A.
Published: October 2003

An examination is made of US policy towards and participation in several key regional multilateral organizations in the Asia–Pacific area, with the aim of establishing how central these organizations are to the overall development of US policy and the extent to which, and how, they influence or constrain US behaviour. The first section of the chapter reviews US strategic goals and briefly discusses some of the domestic and external factors that have led to the development and implementation of these goals in East Asia. The next section discusses multilateral security cooperation in the region, and gives an overview of regional multilateral security organizations, focusing primarily on the ASEAN (Association of Southeast Asian Nations) Regional Forum (ARF), given its all‐encompassing nature and relatively advanced (by Asian standards) stage of development; other US‐instigated multilateral institutions and initiatives (the Korean Peninsula Energy Development Organization (KEDO), and the Northeast Asia Cooperation Dialogue (NEACD) are touched upon briefly to assess how these more narrowly focused approaches also serve American interests. The third section looks at Asia–Pacific multilateral economic cooperation, and here the Asia Pacific Economic Cooperation forum (APEC) provides the centrepiece of the discussion; its role both in creating an Asia–Pacific economic community and, more recently, as a vehicle for political cooperation through the institutionalization of the US‐instigated Leaders’ Meetings, which bring many of the region's heads of state and government together annually, ostensibly for economic discussions. The conclusion to the chapter briefly evaluates the advantages and disadvantages of these organizations from a US perspective in order to understand better how security and economic multilateralism fits with the largely bilaterally oriented US national security strategy.
Power Multiplied or Power Restrained? the United States and Multilateral Institutions in the Americas
Authors: Klepak Hal
Published: October 2003

The central argument is that US power, once established as predominant in the hemisphere, has been nothing short of decisive in the founding, nature, and functioning of the regional multilateral institutions/organizations in the Americas in which it has taken part. The examples of the Pan American Union (PAU) Organization of American States (OAS) and of the North American Free Trade Agreement (NAFTA) are used to show this state of affairs in play; the most attention is paid to the OAS because of the lessons that can be derived from the very long history of US membership of this organization. In another case, that of Mercado Comun del Sur (Mercosur, or the Common Market of the South), it is shown how, even where the US is not a member of a multilateral organization in the hemisphere, its weight is still felt in terms of the aims and behaviour of that body. At the same time, it is seen that such organizations may on occasion be useful for the smaller states in restraining to at least some extent US behaviour, although in general such a restraining role is reserved for moments when US vital interests tend not to be involved and where Latin American, or more recently Canadian, actions to limit US unilateralism do not negatively affect goals perceived to be key by Washington. The first section gives an overview of the US and the hemisphere over the more than two centuries of its diplomatic and related action therein, the next looks at the specific experience of the PAU and the OAS, and the following two at NAFTA and Mercosur.
After the Evil—What?
Authors: Harries Richard
Published: October 2003

Theological responses to the holocaust by scholars such as Fackenheim, Berkovits, Greenburg, and Rubenstein are all finally inadequate and it may be that silence and seeking to repair the world (Tikkun Olam) are what is required of us.
Jewish and Christian Responses to Suffering
Authors: Harries Richard
Published: October 2003

Traditionally, Judaism and Christianity were thought to have very different understandings of suffering. This is not the case. Whilst traditional answers to do with punishment or suffering as character‐building are rejected, there is in both religions an emphasis upon human responsibility, a sharing by God in human suffering, and a call to bring good out of evil. The concept of an afterlife cannot simply be dismissed. But a sense of protest against suffering, which is strong in Judaism, remains an important moral pointer.
Forgive and Forget?
Authors: Harries Richard
Published: October 2003

Traditionally, Christianity has been thought of as a religion of forgiveness and Judaism has been stereotyped as reluctant to forgive. But there is an emphasis on the importance of forgiveness, with repentance, in Judaism and it is possible for Christians to speak too easily of forgiveness. In what way at all, if any, is it possible to seek forgiveness on behalf of others? Can the Catholic Church, e.g., express sorrow for what its past members did to Jews and what validity has this? Is there such thing as collective guilt and can there be collective forgiveness?
The Covenant With Humanity
Authors: Harries Richard
Published: October 2003

In recent years, there has been a debate about whether there is one covenant, with Judaism, onto which Christianity is grafted or whether there are two covenants, one with Judaism, which is primarily social, and one with Christianity, which is primarily with individuals. In fact, the primal covenant, the Noahide covenant, is with humanity, and Judaism and Christianity, like other religions, have their own distinctive voices in response to this. However formulated, it is vital for the church to overcome supersessionism, and the work of scholars such as Pawlikowski are discussed in this connection. It is argued that if we are to think of a difference between the two religions, it may be that Judaism is a religion of the Torah and Christianity is a religion of participation.
Should Christians Try to Convert Jews?
Authors: Harries Richard
Published: October 2003

Mission is fundamental to the life of the Christian church and there has been much controversy in recent decades about whether Christians should continue to try to convert Jews. Christianity needs to create a new relationship with Judaism and dialogue offers an appropriate expression of this. The role of Messianic Jews is particularly controversial. Jewish Christians have brought many gifts to the church, but a Christian prayer for Jews should primarily be one of thankfulness.
Israel in Christian Thought
Authors: Harries Richard
Published: October 2003

The best case for Israel was put by an Anglican scholar, James Parkes, who put forward reasons that were little understood even by Jews at the time. Nevertheless, he acknowledged Palestinian suffering and believed it would need to be recognized and righted. After World War II, churches were slow to recognize the state of Israel but ‘Disregard for its safety and welfare is incompatible with concern for the Jewish people’. How far it is possible to go beyond a recognition in terms of international law to a theological basis is a disputed issue.
Regulator of sex-limitation (Rsl) encodes a pair of KRAB zinc-finger genes that control sexually dimorphic liver gene expression
Authors: Krebs Christopher J. , Larkins Leslie K. , Price Ryan , Tullis Kathryn M. , Miller Raymond D. , Robins Diane M.
Published: October 2003

Sexually dimorphic expression of a broad array of liver proteins involved in reproduction and xenobiotic metabolism is induced at puberty by sex-specific growth hormone patterns. An additional control of sex-dependent gene expression is conferred by Regulator of sex-limitation (Rsl) alleles. In variant rsl mice, females inappropriately express the male Sex-limited protein, Slp. We recently showed that a panel of male-specific liver genes is repressed by Rsl, accentuating sex differences in a hormone-independent manner. Here we map rsl to a region on Chromosome 13 comprised exclusively of KRAB (Kruppel-associated box) zinc-finger protein (ZFP) genes. Among eight Rsl candidate (Rslcan) genes within the critical genetic interval, the recent duplicates Rslcan-4 and Rslcan-9 both harbor mutations in rsl mice (partial deletion and splice-site inactivation, respectively). Transgenesis with bacterial artificial chromosome (BAC) clones encompassing Rslcan-4 restores male-specific MUP (major urinary protein) expression to rsl mice, whereas a BAC containing Rslcan-9 rescues sex-specific expression of Slp and cytochrome P450 Cyp2d9. Thus, the Rslcan-4 and Rslcan-9 paralogs partitioned regulation of their target genes during evolution. This demonstrates the first biological role for a set of KRAB zinc-finger repressor proteins and reveals the molecular basis of a gene-silencing pathway critical for sexual dimorphism.
Meiotic double-strand breaks at the interface of chromosome movement, chromosome remodeling, and reductional division
Authors: Storlazzi Aurora , Tessé Sophie , Gargano Silvana , James Françoise , Kleckner Nancy , Zickler Denise
Published: October 2003

Chromosomal processes related to formation and function of meiotic chiasmata have been analyzed in Sordaria macrospora. Double-strand breaks (DSBs), programmed or γ-rays-induced, are found to promote four major events beyond recombination and accompanying synaptonemal complex formation: (1) juxtaposition of homologs from long-distance interactions to close presynaptic coalignment at midleptotene; (2) structural destabilization of chromosomes at leptotene/zygotene, including sister axis separation and fracturing, as revealed in a mutant altered in the conserved, axis-associated cohesin-related protein Spo76/Pds5p; (3) exit from the bouquet stage, with accompanying global chromosome movements, at zygotene/pachytene (bouquet stage exit is further found to be a cell-wide regulatory transition and DSB transesterase Spo11p is suggested to have a new noncatalytic role in this transition); (4) normal occurrence of both meiotic divisions, including normal sister separation. Functional interactions between DSBs and the spo76-1 mutation suggest that Spo76/Pds5p opposes local destabilization of axes at developing chiasma sites and raise the possibility of a regulatory mechanism that directly monitors the presence of chiasmata at metaphase I. Local chromosome remodeling at DSB sites appears to trigger an entire cascade of chromosome movements, morphogenetic changes, and regulatory effects that are superimposed upon a foundation of DSB-independent processes.
Bioinformatics Analysis of Experimentally Determined Protein Complexes in the Yeast Saccharomyces cerevisiae
Authors: Dezső Zoltán , Oltvai Zoltán N. , Barabási Albert-László
Published: October 2003

Many important cellular functions are implemented by protein complexes that act as sophisticated molecular machines of varying size and temporal stability. Here we demonstrate quantitatively that protein complexes in the yeast Saccharomyces cerevisiae are comprised of a core in which subunits are highly coexpressed, display the same deletion phenotype (essential or nonessential), and share identical functional classification and cellular localization. This core is surrounded by a functionally mixed group of proteins, which likely represent short-lived or spurious attachments. The results allow us to define the deletion phenotype and cellular task of most known complexes, and to identify with high confidence the biochemical role of hundreds of proteins with yet unassigned functionality.
Signal Processing and Flagellar Motor Switching During Phototaxis of Halobacterium salinarum
Authors: Nutsch Torsten , Marwan Wolfgang , Oesterhelt Dieter , Gilles Ernst Dieter
Published: October 2003

Prokaryotic taxis, the active search of motile cells for the best environmental conditions, is one of the paradigms for signal transduction. The search algorithm implemented by the cellular biochemistry modulates the probability of switching the rotational direction of the flagellar motor, a nanomachine that propels prokaryotic cells. On the basis of the well-known biochemical mechanisms of chemotaxis in Escherichia coli, kinetic modeling of the events leading from chemoreceptor activation by ligand binding to the motility response has been performed with great success. In contrast to Escherichia coli, Halobacterium salinarum, in addition, responds to visible light, which is sensed through specific photoreceptors of different wavelength sensitivity (phototaxis). Light stimuli of defined intensity and time course can be controlled precisely, which facilitates input-output measurements used for system analysis of the molecular network connecting the sensory receptors to the flagellar motor switch. Here, we analyze the response of halobacterial cells to single and double-pulse light stimuli and present the first kinetic model for prokaryotic cells that couples the signal-transduction pathway with the flagellar motor switch. Modeling based on experimental data supports the current biochemical model of halobacterial phototaxis. Moreover, the simulations demonstrate that motor switching occurs through subsequent rate-limiting steps, which are both under sensory control, suggesting that two signals may be involved in halobacterial phototaxis.
Reconciling Gene Expression Data With Known Genome-Scale Regulatory Network Structures
Authors: Herrgård Markus J. , Covert Markus W. , Palsson Bernhard ø.
Published: October 2003

The availability of genome-scale gene expression data sets has initiated the development of methods that use this data to infer transcriptional regulatory networks. Alternatively, such regulatory network structures can be reconstructed based on annotated genome information, well-curated databases, and primary research literature. As a first step toward reconciling the two approaches, we examine the consistency between known genome-wide regulatory network structures and extensive gene expression data collections in Escherichia coli and Saccharomyces cerevisiae. By decomposing the regulatory network into a set of basic network elements, we can compute the local consistency of each instance of a particular type of network element. We find that the consistency of network elements is influenced by both structural features of the network such as the number of regulators acting on a target gene and by the functional classes of the genes involved in a particular element. Taken together, the approach presented allows us to define regulatory network subcomponents with a high degree of consistency between the network structure and gene expression data. The results suggest that targeted gene expression profiling data can be used to refine and expand particular subcomponents of known regulatory networks that are sufficiently decoupled from the rest of the network.
Emotional perception and neuroendocrine changes
Authors: Codispoti Maurizio , Gerra Gilberto , Montebarocci Ornella , Zaimovic Amir , Augusta Raggi Maria , Baldaro Bruno
Published: October 2003

The present study was designed to investigate the neuroendocrine modifications during affective states. In particular, we investigate if the pleasantness of the stimuli has a different effect on neuroendocrine responses. To address this issue, we compared the effects of pleasant, neutral, and unpleasant pictures on catecholamine, adrenocorticotrophic hormone (ACTH), cortisol, and prolactin plasma levels. Ten male participants were submitted to three experimental sessions, each on one of the three experimental days, a week apart in a counterbalanced order. Although in the subjective arousal rating, pleasant (erotic pictures) and unpleasant stimuli (pictures of mutilated bodies) receive the same high score, a different neuroendocrine pattern was obtained: unpleasant stimuli elicited a decrease in prolactin concentration and increases in noradrenaline, cortisol, and ACTH levels, whereas pleasant slide set viewing induced an increase in prolactin levels. The results suggest that the neuroendocrine system responds selectively to affective motivationally relevant pictures.
The influence of semantic and phonological factors on syntactic decisions: An event‐related brain potential study
Authors: Schiller Niels O. , Münte Thomas F. , Horemans Iemke , Jansma Bernadette M.
Published: October 2003

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event‐related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors.
Cortical sources of event‐related potentials in the prosaccade and antisaccade task
Authors: Richards John E.
Published: October 2003

The cortical sources of event‐related potentials (ERP) were examined in a prosaccade and antisaccade task in college‐age participants. The task included a cue that indicated the spatial location of the target, a cue that indicated the type of eye movement, or no cue. A principal component analysis and equivalent current dipole analysis showed that a peripheral spatial cue resulted in extrastriate activity localized in Brodmann's area 19 whereas a central cue results in activity in areas 19 or 37. This extrastriate activity reflects an enhanced response to the target when attention was directed to that location. The presaccadic ERP activity primarily consisted of a contralateral positive potential and ipsilateral negative potential, localized in Brodmann's areas 8, 10, and 11. The temporal proximity of this cortical activity and its relation to movement cueing suggests it reflects eye movement planning processes.
To err is autonomic: Error‐related brain potentials, ANS activity, and post‐error compensatory behavior
Authors: Hajcak Greg , McDonald Nicole , Simons Robert F.
Published: October 2003

A two‐component event‐related brain potential consisting of an error‐related negativity (ERN/Ne) and positivity (Pe) has been associated with response monitoring and error detection. Both the ERN and Pe have been source‐localized to the anterior cingulate cortex (ACC)—a frontal structure implicated in both cognitive and affective processing, as well as autonomic nervous system (ANS) modulation. The current study sought to examine the relationships among the ERN, the Pe, two autonomic measures, and behavior. Electroencephalogram (EEG), heart rate (HR), and skin conductance (SC) were recorded while subjects performed a two‐choice reaction‐time task. In addition to the characteristic ERN‐Pe complex, errors were associated with larger SCRs and greater HR deceleration. The ERN correlated with the number of errors, but was unrelated to ANS activity and compensatory behavior. Pe, on the other hand, was correlated significantly with SCR, and both SCR and Pe were significantly correlated with post‐error slowing.
Anterior and posterior attentional control systems use different spatial reference frames: ERP evidence from covert tactile‐spatial orienting
Authors: Eimer Martin , Forster Bettina , Van Velzen José
Published: October 2003

To investigate whether processes controlling preparatory covert shifts of spatial attention operate within external and anatomically defined spatial coordinates, lateralized event‐related potentials components sensitive to the direction of attentional shifts were measured in response to visual precues directing attention to the relevant location of tactile events. Participants had to detect infrequent tactile targets delivered to the hand located on the cued side. In different blocks, hands were uncrossed or crossed, so that external and anatomical codes specifying task‐relevant locations were either congruent or incongruent. With uncrossed hands, an anterior directing attention negativity and a posterior directing attention positivity were elicited in the cue‐target interval contralateral to the side of a cued attentional shift. Although the posterior effect was unaffected by hand posture, the anterior effect was delayed and reversed polarity with crossed relative to uncrossed hands. This pattern of results provides new evidence that different spatial coordinate systems may be used by separable attentional control processes. It is suggested that a posterior process operates on the basis of external spatial coordinates, whereas an anterior process is based primarily on anatomically defined spatial codes.
Attention to external stimuli during wakefulness and sleep: Evoked 40‐Hz response and N350
Authors: Kállai Ibolya , Harsh John , Voss Ursula
Published: October 2003

Changes of two components of the auditory event‐related potential, the evoked 40‐Hz response and the N350, were studied during different stages of wakefulness and sleep. The evoked 40‐Hz response has been proposed to represent an attention‐modulating mechanism; the N350 seems to reflect an inhibitory process associated with reduced information processing. Because recent literature suggests that both components reflect opposite mechanisms, an inverse relationship was expected. Ten participants were presented with tone pips while reading, lying awake in bed, and during light sleep, slow wave sleep, and REM sleep. A significant evoked 40‐Hz response was observed during reading and lying awake in bed. N350 was evident in all conditions and, as expected, peaked during light sleep. The hypothesized inverse relationship was confirmed. These findings support former proposals that relate both components to attention. Possibly, the N350 is most pronounced during the sleep transition period because its inhibitory processes have to prevail over the attentional mechanisms (40‐Hz response) to permit sleep onset.
Turn that frown upside down: ERP effects of thatcherization of misorientated faces
Authors: Milivojevic B. , Clapp W. C. , Johnson B. W. , Corballis M. C.
Published: October 2003

When inverted, thatcherized faces appear normal. This may be due to a decrease in configural and an increase in featural processing. It is not known whether this processing is continuous or reflects two distinct processing systems. Using event‐related potentials (ERPs), we investigated the Thatcher effect on thatcherized and normal faces at varying orientations. The ERPs paralleled the perceptual illusion. The effect of thatcherization on upright faces was visible in P1 and N170 ERP components, possibly reflecting attentional engagement due to unpleasantness of thatcherized faces. Effects were also found over two later components, the P250 component, which has been related to configural recognition, and a late parietal component possibly reflecting featural processing. The effect of thatcherization on the two later components decreased gradually (for the P250 component) and abruptly (for the late parietal component) as the faces were rotated away from the upright.
Effects of trial order and differential conditioning on acquisition of differential shock expectancy and skin conductance conditioning to masked stimuli
Authors: Wiens Stefan , Katkin Edward S. , Öhman Arne
Published: October 2003

Research suggests that when people are fear conditioned to masked spiders and snakes (electric shocks are contingent on only spiders or snakes), they acquire a conditional skin conductance response and can predict the occurrence of shocks even though they are unable to identify the masked spiders and snakes. Because in prior studies trial order was not completely random, it is unclear if findings were due to the contingencies from differential conditioning or a restricted trial order or both. When participants were assigned to four groups to disentangle effects of trial order and differential conditioning to masked pictures in acquisition, effects were obtained only for trial order. These findings demonstrate that trial order can result in conditioning. However, because effects were observed even for participants who reported unawareness of the contingency from trial order, results are consistent with the notion of hunches or gut feelings.
Clarifying the emotive functions of asymmetrical frontal cortical activity
Authors: Harmon‐Jones Eddie
Published: October 2003

Asymmetrical activity over the frontal cortex has been implicated in the experience and expression of emotions and motivations. Explanations of the research have suggested that relatively greater left frontal activity is associated with positive affect and/or approach motivation, and that relatively greater right frontal activity is associated with negative affect and/or withdrawal motivation. In past research, affective valence and motivational direction were confounded, as only positive (negative) affects that were associated with approach (withdrawal) motivation were examined. Consequently, this research is unable to address whether asymmetrical frontal activity is associated with affective valence, motivational direction, or some combination of valence and motivation. In this article, I review research on the emotion of anger, a negative emotion often associated with approach motivation, that suggests that asymmetrical frontal cortical activity is due to motivational direction and not affective valence. Methodological and theoretical implications for the study of the frontal asymmetry specifically, and for emotion and motivation more generally, are discussed.
Actomyosin energy turnover declines while force remains constant during isometric muscle contraction
Authors: West Timothy G. , Curtin N. A. , Ferenczi Michael A. , He Zhen‐He , Sun Yin‐Biao , Irving Malcolm , Woledge Roger C.
Published: October 2003

Energy turnover was measured during isometric contractions of intact and Triton‐permeabilized white fibres from dogfish (Scyliorhinus canicula) at 12°C. Heat + work from actomyosin in intact fibres was determined from the dependence of heat + work output on filament overlap. Inorganic phosphate (Pi) release by permeabilized fibres was recorded using the fluorescent protein MDCC‐PBP, N‐(2‐[1‐maleimidyl]ethyl)‐7‐diethylamino‐coumarin‐3 carboxamide phosphate binding protein. The steady‐state ADP release rate was measured using a linked enzyme assay. The rates decreased five‐fold during contraction in both intact and permeabilized fibres. In intact fibres the rate of heat + work output by actomyosin decreased from 134 ±s.e.m. 28 μW mg−1 (n= 17) at 0.055 s to 42% of this value at 0.25 s, and to 20% at 3.5 s. The force remained constant between 0.25 and 3.5 s. Similarly in permeabilized fibres the Pi release rate decreased from 5.00 ± 0.39 mmol l−1 s−1 at 0.055 s to 39% of this value at 0.25 s and to 19% at 0.5 s. The steady‐state ADP release rate at 15 s was 21% of the Pi rate at 0.055 s. Using a single set of rate constants, the time courses of force, heat + work and Pi release were described by an actomyosin model that took account of the transition from the initial state (rest or rigor) to the contracting state, shortening and the consequent work against series elasticity, and reaction heats. The model suggests that increasing Pi concentration slows the cycle in intact fibres, and that changes in ATP and ADP slow the cycle in permeabilized fibres.
Nuclear transfer in rodents
Authors: Mullins Linda J. , Wilmut Ian , Mullins John J.
Published: October 2003

Cloning is the asexual reproduction of an individual, such that the offspring have an essentially identical nuclear genome. Nuclear transfer and cloning have been achieved in a number of species, namely sheep, cows, goats, rabbits, cats and mice, but have been largely unsuccessful, so far, in dogs, primates and rats. Clearly, contributory factors which affect the outcome of successful cloning experiments are not universally applicable to all species. One theme common to all cloning experiments, however, is the overall inefficiency of the process, typically 0–4%. A number of factors contribute to nuclear transfer inefficiency, and we will review mouse cloning experiments, which address these problems, highlighting the importance of donor nucleus choice (somatic or ES cell, fetal or adult, quiescent or actively dividing). Finally, we will summarize the emerging principles which appear to govern nuclear reprogramming and production of clones, and will consider the application of nuclear transfer to the rat.
The effect of recombinant human growth hormone and resistance training on IGF‐I mRNA expression in the muscles of elderly men
Authors: Hameed M. , Lange K. H. W. , Andersen J. L. , Schjerling P. , Kjaer M. , Harridge S. D. R. , Goldspink G.
Published: October 2003

The expression of two isoforms of insulin‐like growth factor‐I (IGF‐I): mechano growth factor (MGF) and IGF‐IEa were studied in muscle in response to growth hormone (GH) administration with and without resistance training in healthy elderly men. A third isoform, IGF‐IEb was also investigated in response to resistance training only. The subjects (age 74 ± 1 years, mean ±S.E.M) were assigned to either resistance training with placebo, resistance training combined with GH administration or GH administration alone. Real‐time quantitative RT‐PCR was used to determine mRNA levels in biopsies from the vastus lateralis muscle at baseline, after 5 and 12 weeks in the three groups. GH administration did not change MGF mRNA at 5 weeks, but significantly increased IGF‐IEa mRNA (237%). After 12 weeks, MGF mRNA was significantly increased (80%) compared to baseline. Five weeks of resistance training significantly increased the mRNA expression of MGF (163%), IGF‐IEa (68%) and IGF‐IEb (75%). No further changes were observed after 12 weeks. However, after 5 weeks of training combined with GH treatment, MGF mRNA increased significantly (456%) and IGF‐IEa mRNA by (167%). No further significant changes were noted at 12 weeks. The data suggest that when mechanical loading in the form of resistance training is combined with GH, MGF mRNA levels are enhanced. This may reflect an overall up‐regulation of transcription of the IGF‐I gene prior to splicing.
A circadian clock in the fish retina regulates dopamine release via activation of melatonin receptors
Authors: Ribelayga Christophe , Wang Yu , Mangel Stuart C.
Published: October 2003

Although many biochemical, morphological and physiological processes in the vertebrate retina are controlled by a circadian (24 h) clock, the location of the clock and how the clock alters retinal function are unclear. For instance, several observations have suggested that dopamine, a retinal neuromodulator, may play an important role in retinal rhythmicity but the link between dopamine and a clock located within or outside the retina remains to be established. We found that endogenous dopamine release from isolated goldfish retinae cultured in continuous darkness for 56 h clearly exhibited a circadian rhythm with high values during the subjective day. The continuous presence of melatonin (1 nm) in the culture medium abolished the circadian rhythm of dopamine release and kept values constantly low and equal to the night‐time values. The selective melatonin antagonist luzindole (1  μm) also abolished the dopamine rhythm but the values were high and equal to the daytime values. Melatonin application during the late subjective day introduced rod input and reduced cone input to fish cone horizontal cells, a state usually observed during the subjective night. In contrast, luzindole application during the subjective night decreased rod input and increased cone input. Prior application of dopamine or spiperone, a selective dopamine D2‐like antagonist, blocked the above effects of melatonin and luzindole, respectively. These findings indicate that a circadian clock in the vertebrate retina regulates dopamine release by the activation of melatonin receptors and that endogenous melatonin modulates rod and cone pathways through dopamine‐mediated D2‐like receptor activation.
Bypassing a Kinase Activity with an ATP-Competitive Drug
Authors: Papa Feroz R. , Zhang Chao , Shokat Kevan , Walter Peter
Published: October 2003

Unfolded proteins in the endoplasmic reticulum cause trans-autophosphorylation of the bifunctional transmembrane kinase Ire1, which induces its endoribonuclease activity. The endoribonuclease initiates nonconventional splicing of
HAC1
messenger RNAto trigger the unfolded-protein response (UPR). We explored the role of Ire1's kinase domain by sensitizing it through site-directed mutagenesis to the ATP-competitive inhibitor 1NM-PP1. Paradoxically, rather than being inhibited by 1NM-PP1, drug-sensitized Ire1 mutants required 1NM-PP1 as a cofactor for activation. In the presence of 1NM-PP1, drug-sensitized Ire1 bypassed mutations that inactivate its kinase activity and induced a full UPR. Thus, rather than through phosphorylation per se, a conformational change in the kinase domain triggered by occupancy of the active site with a ligand leads to activation of all known downstream functions.
Thermal Stability of Au/NbOx/Nb and Au/Nb2O5/W Model Catalysts Studied by Angle-Resolved X-Ray Photoelectron Spectroscopy
Authors: Lykhach Yaroslava , Plšek Jan , Spirovová Ilona , Bastl Zdeněk
Published: October 2003

The thermal stability of gold deposited on Nb2O5/W, Nb2O5/Nb and NbO/Nb substrates was investigated by angle-resolved X-ray photoelectron spectroscopy. Gold in amounts 0.1-1.2 monolayer was vapour-deposited on an oxide substrate under ultrahigh vacuum. A shift of the Au (4f) core level towards higher binding energies and an increase in the line width with decreasing surface coverage by Au were observed for all supports and explained by final state effects in the photoemission process. The lower magnitude of the shift observed in the case of Au/NbO/Nb was attributed to better screening of the core hole by electrons of the metallic NbO phase. The results present evidence that on heating of the Au/Nb2O5/W system up to 550 °C only agglomeration occurred without significant diffusion of Au into the oxide substrate. Annealing of the Au/Nb2O5/Nb model catalyst above 350 °C resulted in reduction of Nb2O5 to suboxides and inward diffusion of Au. Diffusion into the substrate above 350 °C has also been observed for the Au/NbO/Nb sample. The distribution of Au within the surface layers of substrate has been estimated by analysis of Au (4f) and Nb (3d) angle-resolved spectra. The inward diffusion of Au on annealing observed for the Nb2O5/Nb and NbO/Nb substrates is facilitated by a high density of defects in NbO. Besides information on the particular Au/Nb2O5/W, Au/Nb2O5/Nb and Au/NbO/Nb systems, our results demonstrated potentials of angle-resolved photoelectron spectroscopy for determination of the distribution of a metal in annealed model catalysts and for study of extended interfaces.
Contribution of Fe and Protonic Sites in Calcined and Steamed ZSM-5 Zeolites to Oxidation of Benzene with N2O to Phenol and Selective Catalytic Reduction of NO with Propane to Nitrogen
Authors: Čapek Libor , Kubánek Petr , Wichterlová Blanka , Sobalík Zdeněk
Published: October 2003

NH4-(Fe)ZSM-5 zeolites with concentrations of Fe ranging from 30 to 2000 ppm, introduced into zeolites during their synthesis, either calcined in dry oxygen at 720 K or steamed at 870 K in oxygen stream with 30% water vapor, were investigated in benzene oxidation with N2O to phenol and selective catalytic reduction of NOx to nitrogen. The concentration of Brönsted and Lewis sites was determined by quantitative analysis of IR spectra of adsorbed d3-acetonitrile. The changes in Fe ion coordination were monitored by ESR spectra of Fe(III) ions. The Fe ions have been shown to control the activity of zeolites in the above reactions, while the Al-related acid sites play only a minor role. The steamed zeolites compared to calcined ones exhibited substantially higher activity in oxidation of benzene with N2O to phenol, while the reduction of NOx to nitrogen was considerably suppressed. The steaming resulted in a dramatic decrease in concentration of Brönsted sites, low concentration of Lewis sites and relocalization of Fe ions into cationic sites exhibiting distorted tetrahedral coordination (ESR signals at g = 6.0 and 5.6). It has been concluded that specific Fe sites are required for benzene oxidation to phenol without participation of Brönsted sites, while with the complex SCR-NOx reaction both Fe cationic sites and protonic sites are involved in the catalytic process. Fe sites contribute to oxidation of NO to NO2 and protonic sites control reduction of NO2 to molecular nitrogen.
Reaction Pathways and the Role of Solvent in the Hydrogenation of Chloronitrobenzenes
Authors: Krátky Vieroslav , Králik Milan , Kaszonyi Alexander , Stolcová Magdaléna , Zalibera Lubomír , Mecárová Miroslava , Hronec Milan
Published: October 2003

Liquid phase hydrogenation of chloronitrobenzenes to corresponding chloroanilines over Pd on carbon (Pd/C) under mild reaction conditions was studied. On the basis of 1H, 13C NMR, GC-MS and HPLC analyses of reaction mixtures, the reaction pathways were evaluated. The reduction of substrates proceeds via the formation of chloronitrosobenzenes and N-(chlorophenyl)hydroxylamines and mainly results in the formation of the chloroanilines and aniline. Aniline is formed by hydrogenolysis of chlorine (dechlorination) in benzene ring. Other compounds (mono- and disubstituted azobenzenes and azoxybenzenes) were also detected by GS-MS and HPLC (<3 mole %). The used solvent influences the reaction mixture composition and catalyst activity.
Theoretical Study of Pyrrole Interaction with Alkali Metal Exchanged Zeolites: Investigation of the Reliability of Cluster and Periodic Models
Authors: Kučera Jan , Nachtigall Petr
Published: October 2003

The interaction of pyrrole with the alkali metal exchanged zeolites was investigated using cluster models of various sizes and with a hybrid quantum mechanics/interatomic potential function model (QM-pot). The interaction of pyrrole with the M+/zeolite is dominantly driven by the interaction of pyrrole π-system with the alkali metal cation. Further stabilization is due to the formation of the hydrogen bonds between NH and framework oxygen atoms. A good agreement between calculated and experimental shift of the N-H stretching vibration upon the adsorption of pyrrole in M+/zeolite was found with the periodic QM-pot model. The performance of the cluster models for the description of pyrrole interaction with M+/zeolite is discussed. Reliable results can be obtained only when large cluster models are used for description of the zeolite framework.
Hybrid Catalysts for Acetylenes Polymerization Prepared by Anchoring [Rh(cod)Cl]2 on MCM-41, MCM-48 and SBA-15 Mesoporous Molecular Sieves - The Effect of Support Structure on Catalytic Activity in Polymerization of Phenylacetylene and 4-Ethynyl-N-{4-[(trimethylsilyl)ethynyl]benzylidene}aniline
Authors: Balcar Hynek , Sedláček Jan , Svoboda Jan , Žilková Naděžda , Rathouský Jiří , Vohlídal Jiří
Published: October 2003

Hybrid catalysts for polymerization of acetylenes were prepared by anchoring, via (3-aminopropyl)trimethoxysilane linker, the [Rh(cod)Cl]2 complex on siliceous mesoporous molecular sieves differing in the pore size and architecture (MCM-41, MCM-48 and SBA-15). In comparison with [Rh(cod)Cl]2 used as homogeneous catalyst, all hybrid catalysts exhibited comparable or even higher catalytic activity in the polymerization of phenylacetylene and 4-ethynyl-N-{4-[(trimethylsilyl)ethynyl]benzylidene}aniline. The initial polymerization rate increased with increasing accessibility of mesoporous surface of catalysts in the order: MCM-41 < MCM-48 < SBA-15. Molecular weights of the prepared polymers increased in reverse order suggesting suppression of the chain growth termination reactions by space limitations in the pores. No effect of catalyst support on the microstructure of formed polymers was found.
Synthesis of Diferrocenylethyne by Molybdenum-Catalyzed Metathesis of 1-Ferrocenylprop-1-yne
Authors: Kotora Martin , Nečas David , Štěpnička Petr
Published: October 2003

Diferrocenylethyne (1) was synthesized by metathesis of 1-ferrocenylprop-1-yne using various catalytic systems based on [Mo(CO)6] (5 mole %) and a chlorophenol (30 mole %) in toluene. The yields varied for different chlorophenols; the best conversions were obtained with 2,5-dichlorophenol (66%) and 4-chlorophenol (55%). Alkyne 1 was further reduced to the known (E)-1,2-diferrocenylethene and 1,2-diferrocenylethane, and its solid-state structure determined by single-crystal X-ray diffraction.
Synthesis and Characterisation of Ordered Mesoporous Acid Catalysts for Synthesis of Biodegradable Surfactants
Authors: Boveri Marcelo , Agúndez Javier , Díaz Isabel , Pérez-Pariente Joaquín , Sastre Enrique
Published: October 2003

Solid acid catalysts based on -SO3H-grafted MCM-41 mesoporous silica were prepared as catalysts for the synthesis of biodegradable surfactants leading reactions. The influence of hydrothermal synthesis time on properties of the mesoporous matrix and catalytic activity and selectivity of the catalysts in the stearic acid-glycerol esterification were studied.
Selective Hydrogenation of α,β-Unsaturated Aldehydes on Ru-Sn/TiO2 Catalysts
Authors: Špringerová Jana , Kačer Petr , Hájek Jan , Červený Libor
Published: October 2003

Selective catalytic hydrogenation of unsaturated carbonyl compounds was studied on bimetallic Ru-Sn/TiO2 catalysts. The catalysts were prepared by a sol-gel method and co-impregnation in order to evaluate selected parameters (amount of the modifying tin, TiO2 support - commercial, standard sol-gel, modified sol-gel) on their catalytic activity and selectivity. Significant tin effect was proved especially with regard to the positive influence on selectivity. Sol-gel modified TiO2 was found to be the optimum support. Furthermore, the effect of substrate was studied. The suitability of the catalytic system for hydrogenation of unsaturated aldehydes was proved but it is not suitable for selective hydrogenation of unsaturated ketones.
Photocatalytic Oxidation of Cyclohexene on Titanium(IV) Oxide
Authors: Klisáková Jana , Klusoň Petr , Červený Libor
Published: October 2003

Photocatalytic oxidation of cyclohexene was carried out over a series of titanium(IV) oxide catalysts. These species acting together with molecular oxygen significantly differed in their surface and structural properties. Attention was paid to elimination of the total decomposition of the alkene molecules to water and carbon dioxide and to favour formation of reaction intermediates, comprising epoxide units. Experiments were performed in liquid phase at atmospheric pressure, room temperature and under UV illumination. A quartz reactor was used and the reaction mixture was agitated by oxygen. Significant variations in the reaction selectivity were detected as a function of catalyst structural properties.
(Al)MCM-41 Molecular Sieves. Aluminium Distribution, Uniformity and Structure of Inner Surface
Authors: Dědeček Jiří , Žilková Naděžda , Kotrla Josef , Čejka Jiří
Published: October 2003

The effect of the framework Al content and synthesis procedure on the number of framework Al atoms located on the surface of (Al)MCM-41 channels and the distribution of the Al atoms between single Al atoms and various Al-O-(SiO)1,2-Al species was investigated. The total number of accessible framework Al atoms on the channel surface was obtained from the ion exchange capacity for Na+ ions and pyridine adsorption. The number of Al pairs on the surface and their distribution between different local arrangements of the channel surface was estimated using VIS spectroscopy of Co2+ ions. At low framework Al contents, Al atoms occupy only accessible T sites on the surface of the channel walls. In aluminium-rich (Al)MCM-41, a significant part of Al atoms is incorporated inside the channel walls and these Al atoms do not form cationic sites. Al atoms on the wall surface preferentially form Al-O-(SiO)1,2-Al sequences, enabling siting of divalent cations. Different synthesis procedures resulted in differences in Al distribution. The channel surface of the (Al)MCM-41 is formed by two regular local structures containing two types of deformed six-membered rings with Al-O-(SiO)1,2-Al sequences forming cationic sites.
Preparation of Organized Mesoporous Silica from Sodium Metasilicate Solutions in Alkaline Medium Using Nonionic Surfactants
Authors: Zukalová Markéta , Rathouský Jiří , Zukal Arnošt
Published: October 2003

A new procedure has been developed, which is based on homogeneous precipitation of organized mesoporous silica from an aqueous solution of sodium metasilicate and a nonionic poly(ethylene oxide) surfactant serving as a structure-directing agent. The decrease in pH, which induces the polycondensation of silica, is achieved by hydrolysis of ethyl acetate. Owing to the complexation of Na+ cations by poly(ethylene oxide) segments, assembling of the mesostructure appears to occur under electrostatic control by the S0Na+I- pathway, where S0 and I- are surfactant and inorganic species, respectively. As the complexation of Na+ cations causes extended conformation of poly(ethylene oxide) segments, the pore size and pore volume of organized mesoporous silica increase in comparison with materials prepared under neutral or acidic conditions. The assembling of particles can be fully separated from their solidification, which results in the formation of highly regular spherical particles of mesoporous silica.
Expanding the forest management framework in the province of Alberta to include landscape-based research
Authors: Smith Daniel W , Russell J S , Burke J M , Prepas E E
Published: October 2003

The Forest Watershed and Riparian Disturbance (FORWARD) project was initiated in the western Canadian province of Alberta, the site of some of the most intensive forest activities on the Boreal Plain subregion of the Canadian Boreal Forest, including forestry, oil and gas extraction, and mining. Forest management falls primarily within provincial/territorial jurisdiction in Canada; therefore, we outline the processes for forest management planning and practices at the provincial level. In Alberta, the Ministry of Sustainable Resource Development allocates tenure of forested areas to forest products companies via forest management agreements (FMAs). Conditions for company activities in the FMA area are cooperatively designed and documented in detailed forest management plans. We examine Alberta Government policies with respect to watershed management in forested areas, with an emphasis on aquatic ecosystems. Further, needs for changes to current government policy and practices are discussed, with recognition of the pressures that exist on the regulatory effort. Key words: forest management, forest harvest, regulation, policy, legislation.