bluuebunny/crossref_metadata_2025 huggingface dataset:
‘O‐Acyl isopeptide method’ for peptide synthesis: Solvent effects in the synthesis of Aβ1–42 isopeptide using ‘O‐acyl isodipeptide unit’
Authors: Taniguchi Atsuhiko , Yoshiya Taku , Abe Naoko , Fukao Fukue , Sohma Youhei , Kimura Tooru , Hayashi Yoshio , Kiso Yoshiaki
Published: September 2007

‘O‐Acyl isopeptide method’ is an efficient synthetic method for peptides. We designed ‘O‐acyl isodipeptide units’, Boc‐Ser/Thr(Fmoc‐Xaa)‐OH, as important building blocks to enable routine use of the O‐acyl isopeptide method. In the synthesis of an Aβ1–42 isopeptide using O‐acyl isodipeptide unit Boc–Ser(Fmoc–Gly)–OH, a side reaction, resulting in the deletion of Ser26 in the O‐acyl isopeptide structure, was noticed during coupling of the unit. We observed that the side reaction occurred during the activation step and was solvent‐dependent. In DMF or NMP, an intramolecular side reaction, originating from the activated species of the unit, occurred during the activation step. In non‐polar solvents such as CHCl3 or CH2Cl2, the side reaction was less likely to occur. Using CH2Cl2 as solvent in coupling the unit, the target Aβ1–42 isopeptide was synthesized with almost no major side reaction. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Growth of InN crystals with peculiar morphology by means of AP‐HCVD: Computational fluid‐dynamics simulation of the gas flowing in the reactor
Authors: Sugiura H. , Takahashi N. , Nakamura T.
Published: September 2007

Indium nitride crystals were grown by a halide chemical vapor deposition technique under atmospheric pressure. Scanning electron microscopic observation showed that InN crystals have flower‐like morphology with six petals. Computational fluid‐dynamics simulation was applied to study the fluid behavior in a quartz‐tube reactor used for the crystal growth. The obtained results showed that the gas flow was laminar in most areas of the reactor. No turbulent flow was observed in the vicinity of the substrate. The temperature was confirmed as less than 823 ± 0.3 K in the same area. As a result, it is deduced that the precise control of both gas flow and temperature results in the flower‐like InN crystals with high reproducibility. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Associations of watershed vegetation and environmental variables with fish and crayfish assemblages in headwater streams of the Pedernales River, Texas
Authors: Birnbaum J. S. , Winemiller K. O. , Shen L. , Munster C. L. , Wilcox B. P. , Wilkins R. N.
Published: September 2007

Intermittent headwater streams serve important functions for humans and wildlife in semi‐arid rangelands. Increases in ashe juniper coverage in central Texas over recent decades are believed to have negatively impacted stream flows. Few studies have examined relationships between aquatic species and environmental factors in these systems as well as the influence of juniper coverage on assemblage structure. During summer 2003 and spring 2004, we examined species–environment relationships to infer potential effects of juniper cover on aquatic ecology relative to local‐scale and watershed‐scale environmental variables. Fish and crayfish species assemblages and physicochemical variables were investigated in spring‐fed headwater tributaries of the Pedernales River, Texas. Fish abundance was much higher in summer 2003, whereas crayfish abundance was higher in spring 2004. Fish species richness was lower during spring 2004, possibly due to below average precipitation during spring 2004 that reduced deep‐water refugia. Higher abundance of crayfish in spring 2004 samples was probably due to their ability to survive low‐flow conditions, and a release from fish predation pressure. Fish assemblage structure was more strongly associated with local abiotic factors during spring 2004 when flow was reduced, whereas structure during summer 2003 samples suggested a relatively greater influence of predation. In general, juniper cover was weakly associated with fish and crayfish assemblages, although it tended to be positively associated with relatively high‐quality habitat for sensitive taxa (flowing runs with coarse substrate; deep, connected pools). We suggest that intermediate levels of juniper cover in the region provide indirect benefits to aquatic organisms. However, short‐term, local environmental factors appear to have a much greater influence than watershed vegetation on fish and crayfish assemblages in these intermittent streams. Copyright © 2007 John Wiley & Sons, Ltd.
Students' cognitive focus during a chemistry laboratory exercise: Effects of a computer‐simulated prelab
Authors: Winberg T. Mikael , Berg C. Anders R.
Published: September 2007

To enhance the learning outcomes achieved by students, learners undertook a computer‐simulated activity based on an acid–base titration prior to a university‐level chemistry laboratory activity. Students were categorized with respect to their attitudes toward learning. During the laboratory exercise, questions that students asked their assistant teachers were used as indicators of cognitive focus. During the interviews, students' frequency and level of “spontaneous” use of chemical knowledge served as an indicator of knowledge usability. Results suggest that the simulation influenced students toward posing more theoretical questions during their laboratory work and, regardless of attitudes, exhibiting a more complex, correct use of chemistry knowledge in their interviews. A more relativistic student attitude toward learning was positively correlated with interview performance in both the control and treatment groups. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 1108–1133, 2007
Effect of housing and environmental enrichment on adrenocortical activity, behavior and reproductive cyclicity in the female tigrina (Leopardus tigrinus) and margay (Leopardus wiedii)
Authors: Moreira Nei , Brown J.L. , Moraes W. , Swanson W.F. , Monteiro‐Filho E.L.A.
Published: September 2007

The objective of this study was to evaluate the effects of different captive housing conditions on reproductive cyclicity and adrenocortical activity in adult females of two small‐sized felid species, the tigrina (Leopardus tigrinus; n = 3) and margay (Leopardus wiedii; n = 2). Females were housed as singletons and subjected to three enclosure conditions over successive time periods: Phase I—large, enriched enclosures for 3 months; Phase II—small, empty enclosures for 5.5 months; Phase III—the same small enclosures enriched with branches and nest boxes for 6.5 months. Fecal samples were collected five times weekly throughout the study for analysis of progestagen, estrogen, and corticoid metabolites. On the basis of observed behaviors, stereotypic pacing was more frequent before feeding for all cats, regardless of enclosure conditions. Both species displayed a bimodal activity pattern, with peaks occurring at nightfall and dawn. All animals exhibited agitated behavior, characterized by a high frequency and duration of stereotypic pacing, primarily during the first 3 days after moving to the small empty enclosures. On the basis of hormonal analyses, ovarian follicular activity decreased and corticoid concentrations increased in tigrinas after transfer to the small barren cages compared to the patterns observed in the initial large, enriched enclosures. Corticoid concentrations in tigrinas then declined after small cage enrichment. Margay females exhibited increased corticoid excretion during Phases II and III, but in contrast to tigrinas, concentrations remained high even after cage enrichment. It was further showed that enriching the small enclosures was insufficient to reestablish normal ovarian activity within the time frame of the study for both species. In summary, margay and tigrina females exhibited distinct elevations in corticoid concentrations after transfer from large enriched enclosures to smaller barren cages that corresponded with agitated behavior, especially immediately after transfer. Fecal corticoid concentrations were reduced after cage enrichment in tigrinas, but not in margays. Although only a few individuals were evaluated, data suggest there may be species differences in response to captive environmental conditions. Overall results emphasize the importance of enclosure dimensions and enrichment when designing species appropriate environments for improving the health and reproductive fitness of threatened species. Zool Biol 26:441–460, 2007. © 2007 Wiley‐Liss, Inc.
Melatonin: New Places in Therapy
Authors: Maharaj Deepa S. , Glass Beverley D. , Daya Santy
Published: September 2007

The fact that the full extent of the function of the pineal gland has not yet been elucidated, has stimulated melatonin research worldwide. This review introduces melatonin's mechanism of action, direct and indirect antioxidant actions as well as the antioxidant properties of its metabolites, 6-hydroxymelatonin (6-OHM) and N-acetyl-N-formyl-5-methoxykynurenamine (AFMK). At present the mechanism of action is proposed to be receptor-, protein- and nonprotein-mediated. From its popular role in the treatment of jetlag, melatonin is now implicated in the reduction of oxidative stess, both as a free radical scavenger and antioxidant. Melatonin's direct scavenging action in respect of the following will be discussed: superoxide anions, hydrogen peroxide, hydroxyl radicals, singlet oxygen, peroxy radicals and nitric oxide/peroxy nitrite anions. In addition melatonin also possesses indirect antioxidant activity and the role of its metabolites, AFMK and 6-OHM will be presented. It is these free radical scavenging and antioxidant properties of melatonin that has shifted the focus from that of merely strengthening circadian rhythms to that of neuroprotectant: a new place in therapy.
Divergent effect of proteasome inhibition on interleukin‐1β and tumor necrosis factor α signaling in human astroglial cells
Authors: Choi Kyungsun , Lee Jungsul , Choi Chulhee
Published: September 2007

Impaired functioning of the proteasome pathway is one of the molecular mechanism underlying neurodegenerative changes in Alzheimer's disease. In this study, we report that dysfunction of the proteasome pathway in astroglial cells leads to decreased survival and dysregulation of chemokines by differential regulation of the nuclear factor kappa B and c‐jun N‐terminal kinase (JNK) pathways. We further demonstrated that proteasome inhibition augmented interleukin‐1 β‐ and tumor necrosis factor‐α‐induced activation of the IκBα kinase and MKK4/JNK/c‐Jun pathway along with TAK1 activation. These results suggest that impaired function of the proteasome pathway may potentiate the immuno‐pathologic role of secondarily activated astrocytes in the brain.
Role of nitric oxide in cerebrovascular reactivity to NMDA and hypercapnia during prenatal development in sheep
Authors: Harris Andrew P. , Ohata Hiroto , Koehler Raymond C.
Published: September 2007

Cerebral vasodilatory responses evoked by activation of NMDA receptors and by hypercapnia are important factors in the integrated vascular response to perinatal cerebral ischemia. Cerebral vasodilation to NMDA is mediated by nitric oxide in adult and newborn animals, whereas vasodilation to hypercapnia is thought to become modulated by nitric oxide, at least in swine, after the newborn period. The developmental role of nitric oxide in the cerebral blood flow response to NMDA and hypercapnia was investigated at mid‐ and late gestation in fetal sheep. Superfusion of 300 μM NMDA over the cerebral cortex through a closed cranial window on the exteriorized head of an anesthetized fetus increased laser‐Doppler flow by 41 ± 7% (±S.E.) at 0.65 gestation. The increase was reduced by superfusion of a nitric oxide synthase inhibitor (18 ± 8%). At 0.9 gestation, the response to NMDA was augmented (85 ± 24%) compared to that at 0.65 gestation and was reduced by a nitric oxide synthase inhibitor (32 ± 6%). In unanesthetized fetal sheep, hypercapnic reactivity of microsphere‐determined cerebral blood flow was not significantly attenuated by nitric oxide synthase inhibition at 0.65 gestation (4.6 ± 0.7 to 3.7 ± 1.0% change/mmHg pCO2) or at 0.9 gestation (4.0 ± 0.7 to 3.5 ± 0.9% change/mmHg pCO2). Therefore, nitric oxide‐dependent cerebrovascular dilation to NMDA‐receptor activation is present as early as 0.65 gestation in fetal sheep and increases further during the last trimester, whereas vasodilation to hypercapnia remains unchanged and independent of nitric oxide during the last trimester. Hence, cerebrovascular reactivities to different stimuli do not mature concurrently.
Correlations between Academic Achievement and Anxiety and Depression in Medical Students Experiencing Integrated Curriculum Reform
Authors: Yeh Yi‐Chun , Yen Cheng‐Fang , Lai Chung‐Sheng , Huang Chun‐Hsiung , Liu Keh‐Min , Huang In‐Ting
Published: September 2007

This study aimed to examine the correlations between academic achievement and levels of anxiety and depression in medical students who were experiencing curriculum reform. The differences in academic achievement and the directions of correlations between academic achievement and anxiety and depression among the medical students with different levels of anxiety and depression were also examined. Grade 1 students from graduate‐entry program and grade 3 students from undergraduate‐entry program in their first semester of the new curriculum were recruited to complete the Zung's Anxiety and Depression Scale twice to examine their levels of anxiety and depression. Their academic achievement ratings in the four blocks of the first semester of the new curriculum were collected. The results indicated that no significant correlation was found between academic achievement and global anxiety and depression. However, by dividing the medical students into low, moderate and high level anxiety or depression groups, those who had poorer academic achievement in the first learning block were more likely to have higher levels of depression in the first psychologic assessment. Among the medical students who were in the high anxiety level group in the first psychologic assessment, those who had more severe anxiety had poorer academic achievement in the fourth learning block. Among the medical students who were in the low anxiety level group in the second psychologic assessment, those who had more severe anxiety had better academic achievement in the fourth learning block. Among the medical students who were in the moderate anxiety level group in the second psychologic assessment, those who had more severe anxiety had poorer academic achievement in the second learning block. Among the medical students who were in the high depression level group in the second psychologic assessment, those who had more severe depression had poorer academic achievement in the fourth learning block. The results of this study indicate that there are both positive and negative correlations between academic achievement and anxiety and depression in medical students, regarding differing levels of severity of anxiety or depression. The results could represent a reference for teachers on the planning of teaching and assessment programs.
Effect of Chronic Prostatitis on Angiogenic Activity and Serum Prostate Specific Antigen Level in Benign Prostatic Hyperplasia
Authors: Dogan Koseoglu Resit , Erdemir Fikret , Parlaktas Bekir Suha , Filiz Nurper Onuk , Uluocak Nihat , Etikan Ilker
Published: September 2007

The aim of this study was to evaluate the effect of chronic inflammatory pathology on the angiogenic activity in benign prostatic hyperplasia (BPH). Besides the presence of a relationship between serum prostate specific antigen (PSA) values and microvessel density (mvd), the intensity and extent (widespread or focal) of tissue PSAexpression was also examined. The distribution of 30 cases according to the diagnosis groups was as follows: group 1, nine cases with prostatic adenocarcinoma; group 2, 10 cases with BPH and chronic prostatitis; group 3, 11 cases with BPH. The biopsy materials obtained by tru‐cut biopsy (five cases) and transurethral resection (25 cases) were evaluated retrospectively. The evaluation of angiogenesis was made by CD34 immune marker, while the analysis of immunohistochemical tissue PSA expression was verified by PSA immune marker. Serum PSA levels and other clinical parameters were obtained from the clinical files of the patients. The mean age of the patients was 68 ± 3 years (range, 48–83 years). The difference between the mean mvd values of the groups was statistically significant (χ2 = 10.492, p = 0.005). Group 1 showed higher mean mvd value than the other two groups. Although group 2 showed higher mean mvd value than group 3, the difference was not statistically significant (p = 0.863). There was no correlation between the mean mvd and serum PSA levels in any group. The intensity of PSA expression in prostate specimens was different in all groups. Maximum cases in group 3 showed high tissue PSA expression (χ2 = 12.442, p = 0.014). In group 1, there was a significant relationship between the intensity of PSA expression and the mean mvd (U = 1, p = 0.032). In group 2, a statistically significant correlation was noted between the mean serum PSA levels and the widespread occurrence of PSA expression (U = 0, p = 0.017). In the present study, we determined that chronic prostatitis had no effect on mvd in BPH cases. The correlation between tissue PSA expression and mvd was contradictory to the reports in the literature. Analyses in larger series are needed to prove the presence of a probable effect of chronic prostatitis on angiogenesis.
Admission Time and Outcomes of Patients in A Medical Intensive Care Unit
Authors: Sheu Chau‐Chyun , Tsai Jong‐Rung , Hung Jen‐Yu , Yang Chih‐Jen , Hung Hsin‐Chia , Chong Inn‐Wen , Huang Ming‐Shyan , Hwang Jhi‐Jhu
Published: September 2007

Studies have shown that weekend or night admissions to intensive care units (ICUs) are associated with increased mortality in critically ill patients. Our study aimed to evaluate the effects of admission time and day on patient outcomes in a medical ICU equipped with patient management guidelines, and staffed by intensivists on call for 24 hours, who led the morning rounds on all days of the week but did not stay in‐house overnight. The study enrolled 611 consecutive patients admitted to a 26‐bed medical ICU in a university hospital during a 7‐month period. We divided them into two groups, which we labeled as “office hours” (08:00–18:00 on weekdays) and “non‐office hours” (18:00–08:00 on weekdays, and all times on weekends) according to their ICU admission times. The clinical outcomes were compared between the groups. The effects of admission on weekends, at night, and various days of the week on hospital mortality were also evaluated. Our results showed that there were no significant differences in ICU and hospital mortalities between patients admitted during office hours and those admitted during non‐office hours (27.2% vs. 27.4%, p = 1.000; 38.9% vs. 37.6%, p = 0.798). The ICU length of stay, ICU‐free time within 21 days, and length of stay in the hospital were also comparable in both groups. Among the 392 patients requiring mechanical ventilation, the ventilator outcomes were not significantly different between those in the office‐hour group and the non‐office‐hour group. Multivariate logistic regression analyses showed that the adjusted odds of hospital mortality were not significantly higher for patients admitted to our ICU on weekends, at night, or on any days of the week. In conclusion, our results showed that non‐office‐hour admissions to our medical ICU were not associated with poorer ICU, hospital, and ventilator outcomes, compared with office‐hour admissions. Neither were time of day and day of the week admissions to our ICU associated with significant differences in hospital mortality.
Le français, langue de la diversité
québécoise. Une réflexion pluridisciplinaire
Authors: Rhéaume, Stéphanie
Published: September 2007

Le français, langue de la diversité
québécoise. Une réflexion pluridisciplinaire,
Georgeault, Pierre, et Michel Pagé (dir.), Montréal,
Québec Amérique, 2006, 347 pages.

Pierre Georgeault et Michel Pagé procèdent à une
réflexion multidisciplinaire pertinente et attendue sur la
dynamique des langues et la prise en compte de la pluralité dans la
société québécoise dans l'ouvrage
collectif Le français, langue de la diversité
québécoise. À l'invitation du Conseil
supérieur de la langue française, 15 spécialistes de
la vaste problématique de la langue française se sont
attelés à la tâche d'étudier le concept
d'intégration linguistique et la notion de langue d'usage
public dans le contexte québécois. Ce recueil se consacre de
front à la question linguistique et à
l'intégration de la diversité, problématique
trop souvent négligée ou traitée seulement dans le
prolongement du débat sur la définition de la nation
québécoise. Malgré tout, même cet ouvrage ne
fait pas exception puisqu'il aborde la nécessaire question de
la nation, indubitablement associée à celle de la politique
linguistique. Cependant, l'ouvrage de Georgeault et Pagé
explore aussi d'autres avenues fort intéressantes, comme
celles qu'empruntent les approches socioculturelles et
psychosociologiques.
Minority Rights
Authors: Long Doug
Published: September 2007

Minority Rights, Jennifer Jackson Preece, Cambridge (UK) and
Malden MA: Polity Press, 2005, pp. ix, 213.

This book is not, as its title might be thought to suggest, an
abstract conceptual analysis of a particular sub-set of rights. Although
it builds on, and acknowledges, the work of Kymlicka, Raz, Taylor and
Shklar (160), the narrative thread that gives it unity is historical. It
deepens our understanding of the nature of the discourse of minority
rights by contextualizing that discourse both temporally (through
historical examples) and spatially (through adroitly selected comparative
examples). With extraordinary succinctness and clarity the author guides
us through a succession of political epochs: the time of the Christian and
Islamic medieval universitae, the period of the dynastic re-organization
of Europe, the modern era of popular sovereignty with its attendant
notions of civic and ethnic nationalism, and especially the
contradiction-laden time of European imperialism and its post-imperial and
post-colonial reverberations. As this narrative unfolds we follow the
vicissitudes of religious, racial, linguistic and ethnic minorities and
observe the successive forms taken by the “problem of
minorities.”
The Case for the Enlightenment: Scotland and Naples
1680–1760
Authors: Sabetti Filippo
Published: September 2007

The Case for the Enlightenment: Scotland and Naples
1680–1760, John Robertson, Cambridge: Cambridge University
Press, 2005, pp.xii, 455.

In this book, John Robertson, University Lecturer in Modern History
and Fellow at St. Hugh's College, Oxford, does several things all at
once. The result is one of the most profound and illuminating studies in
comparative historical analysis and political thought published in recent
decades.
Suicide Terrorism
Authors: Zekulin Michael
Published: September 2007

Suicide Terrorism, Ami Pedahzur, Cambridge: Polity, 2005, pp.
264.

With the issue of terrorism continuing to dominate media reports,
there are renewed calls for a better understanding of the most deadly
weapon employed by these organizations: suicide bombing. Ami Pedahzur, in
his book Suicide Terrorism, successfully meets this challenge
head on. It has long been accepted by those who study this issue that
suicide terrorism has been a potent tool both for making grandiose public
statements and as a means of engaging militarily superior opponents or
difficult targets. Pedahzur outlines various methods, including historical
tracing and the analysis of case studies, to further the understanding of
this issue as well as the academic debate which surrounds it.
Women and Politics in Chile
Authors: Richards Patricia
Published: September 2007

Women and Politics in Chile, Susan Franceschet, Boulder CO:
Lynne Rienner Publishers, 2005, pp. x, 203.

The Pinochet dictatorship in Chile (1973–1990) was marked by a
high degree of women's activism focusing on human rights, economic
survival and feminism. Many women expected that their active role during
the dictatorship would lead to a new way of doing politics and greater
inclusion of women in the political process once democracy was restored.
But despite the recent election of Michelle Bachelet as president of
Chile, Chilean women continue to be vastly underrepresented in political
party leadership and elected office. In this clearly written and cogently
argued book, Susan Franceschet addresses the important question of the
marginalization of women from Chilean politics under democracy.
La comparaison dans les sciences sociales : pratiques et
méthodes
Authors: Gingras François-Pierre
Published: September 2007

La comparaison dans les sciences sociales : pratiques et
méthodes, Vigour, Cécile, Paris, La découverte,
2005, 335 pages.

Cet ouvrage, rédigé par une sociologue française
rattachée à l'Institut des sciences sociales du
politique (une unité du CNRS), se présente comme un “
guide repère ” sur la comparaison en sciences sociales.
POTS, WORDS AND THE BANTU PROBLEM: ON LEXICAL RECONSTRUCTION AND EARLY AFRICAN HISTORY
Authors: BOSTOEN KOEN
Published: September 2007

Historical-comparative linguistics has played a key role in the reconstruction of early history in Africa. Regarding the ‘Bantu Problem’ in particular, linguistic research, particularly language classification, has oriented historical study and been a guiding principle for both historians and archaeologists. Some historians have also embraced the comparison of cultural vocabularies as a core method for reconstructing African history. This paper evaluates the merits and limits of this latter methodology by analysing Bantu pottery vocabulary. Challenging earlier interpretations, it argues that speakers of Proto-Bantu inherited the craft of pot-making from their Benue-Congo-speaking ancestors who introduced this technology into the Grassfields region. This ‘Proto-Bantu ceramic tradition’ was the result of a long, local development, but spread quite rapidly into Atlantic Central Africa, and possibly as far as Southern Angola and northern Namibia. The people who brought Early Iron Age (EIA) ceramics to southwestern Africa were not the first Bantu-speakers in this area nor did they introduce the technology of pot-making.
ΕΡΗΑΡΑΧ: The One and the Many in Hebrews
Authors: THOMPSON JAMES W.
Published: September 2007

A consistent feature of the argument of Hebrews is the claim that Christ offered himself ‘once for all’, which the author develops with the qualitative distinction between the one and the many priests (7.23–28) and sacrifices (9.23–10.18). In placing this distinction of the one and the many within the metaphysical dualism of the two spheres of reality, the author reflects assumptions that are also present in the claim of both Philo and Plutarch that the deity is above the principle of multiplicity (Philo Spec. III.180; Abr. 122; Leg. II.2; Deus 82; Plutarch E. Delph. 393e).
Characterisation of Arctic treelines by LiDAR and multispectral imagery
Authors: Rees W. G.
Published: September 2007

The Arctic treeline, or more precisely the tundra-taiga interface (TTI) region, is poorly defined and characterised despite its high climatological significance. The international coordinated research programme ‘PPS Arctic’, under the auspices of the International Polar Year, represents one response to this gap in our knowledge. This paper presents preliminary work within one of the four principal research areas of PPS Arctic, the characterisation of spatial variations in vegetation, land cover and land use in the TTI using remote sensing methods. Airborne remote sensing data were collected from a 120 km2 TTI study site near Porsangmoen, Finnmark, Norway in 2004 and 2005. Three datasets were acquired: two sets of multispectral visible-infrared imagery with spatial resolutions of around 3 m, and airborne scanning LiDAR data with a horizontal resolution of 2 m and a vertical precision of around 0.2 m. While some difficulties were experienced in processing and analysing the imagery, the LiDAR data proved exceptionally well suited to the task of characterising the structure of the forest edge. Preliminary analyses were strongly suggestive of fractal characteristics, with corresponding consequences for the scale-dependence of descriptors such as canopy density and the location of the forest edge.
Topography and displacement of polar glaciers from multi-temporal SAR interferograms
Authors: Meyer Franz J.
Published: September 2007

This paper describes a new technique simultaneously to estimate topography and motion of polar glaciers from multi-temporal SAR interferograms. The approach is based on a combination of several SAR interferograms in a least-squares adjustment using the Gauss-Markov model. For connecting the multi-temporal data sets, a spatio-temporal model is proposed that describes the properties of the surface and its temporal evolution. Rigorous mathematical modelling of functional and stochastic relations allows for a systematic description of the processing chain. It is also an optimal tool to set parameters for the statistics of every individual processing step, and the propagation of errors into the results. Within the paper theoretical standard deviations of the unknowns are calculated depending on the configuration of the data sets. The influence of gross errors in the observations and the effect of non-modelled error sources on the unknowns are estimated. A validation of the approach based on real data concludes the paper.
Longitudinal associations between depressive and anxiety disorders: a comparison of two trait models
Authors: Olino Thomas M. , Klein Daniel N. , Lewinsohn Peter M. , Rohde Paul , Seeley John R.
Published: September 2007

Background

Depression and anxiety are highly co-morbid disorders. Two latent trait models have been proposed to explain the nature of the relationship between these disorders. The first posits that depressive and anxiety disorders are both manifestations of a single internalizing factor. The second model, based on a tripartite model proposed by Clark & Watson [Journal of Abnormal Psychology(1991)100, 316–336], proposes that depressive and anxiety disorders reflect a combination of shared and disorder-specific factors.

Method

We directly compared the two models in a sample of 891 individuals from the Oregon Adolescent Depression Project who participated in up to four diagnostic assessments over approximately 15 years. Structural equation models were used to examine the relationship between depressive and anxiety disorders across different developmental periods (<14, 14–18, 19–23, 24–30 years of age).

Results

The one- and three-factor models were hierarchically related. Thus, a direct comparison between the one- and three-factor models was possible using a χ2difference test. The result found that the three-factor model fit the data better than the one-factor model.

Conclusions

The three-factor model, positing that depressive and anxiety disorders were caused by a combination of shared and disorder-specific factors, provided a significantly better fit to the data than the one-factor model postulating that a single factor influences the development of both depressive and anxiety disorders.
Combined dexamethasone/corticotropin-releasing factor test in chronic fatigue syndrome
Authors: Van Den Eede F. , Moorkens G. , Hulstijn W. , Van Houdenhove B. , Cosyns P. , Sabbe B. G. C. , Claes S. J.
Published: September 2007

Background

Studies of hypothalamic–pituitary–adrenal (HPA) axis function in chronic fatigue syndrome (CFS) point to hypofunction, although there are negative reports. Suggested mechanisms include a reduced hypothalamic or supra-hypothalamic stimulus to the HPA axis and enhanced sensitivity to the negative feedback of glucocorticoids. The aim of the current study was to investigate HPA axis function in CFS with the dexamethasone/corticotropin-releasing factor (Dex/CRF) test, in analogy with research in affective disorders.

Method

Thirty-four well-characterized female CFS patients and 25 healthy control subjects participated in the low-dose Dex/CRF test. Current major depressive episode was an exclusion criterion. History of early-life stress (ELS) was assessed with the Structured Trauma Interview.

Results

Salivary cortisol responses after 0.5 mg Dex were lower in CFS patients than in controls (before 100 μg CRF,p=0.038; after 100 μg CRF,p=0.015). A secondary analysis revealed an influence of early-life stress and of oestrogen intake. After removal of the 10 participants who were taking an oral oestrogen, patients without a history of ELS showed lower cortisol responses than patients with ELS and controls (before CRF,p=0.005; after CRF,p=0.008).

Conclusions

CFS is globally associated with reduced cortisol responses in the combined low-dose Dex/CRF test, but this effect is only clearly present in CFS patients without a history of ELS. This study provides further support for an enhanced glucocorticoid negative feedback and/or a reduced central HPA axis drive in CFS. Furthermore, it demonstrates that ELS is an important variable to consider in CFS research.
Hypercyclic, mixing, and chaoticC0-semigroups induced by semiflows
Authors: KALMES T.
Published: September 2007

We characterize whenC0-semigroups induced by semiflows are hypercyclic, topologically mixing, or chaotic both on spaces of integrable functions and on spaces of continuous functions. Furthermore, we give characterizations of transitivity for weighted composition operators on these spaces.
Restoration of visual function following optic nerve regeneration in bluegill (Lepomis macrochirus) × pumpkinseed (Lepomis gibbosus) hybrid sunfish
Authors: CALLAHAN MICHAEL P. , MENSINGER ALLEN F.
Published: September 2007

Simple (dorsal light reflex) and complex (predator-prey interactions) visually mediated behaviors were used concurrently with morphological examination to assess restoration of visual function following optic nerve crush in bluegill (Lepomis macrochirus) × pumpkinseed (Lepomis gibbosus) hybrid sunfish. Regenerating optic nerve axons projected into thestratum opticum-stratum fibrosum et griseum superficialeby week 2, thestratum griseum centraleby week 4, andstratum album centraleby week 6. Initial projections into the laminae were diffuse and less stratified compared to controls. By week 12, the projection pattern of regenerating nerve fibers closely resembled the innervation of normal tecta. Visual improvements were correlated with increasing projections into the tectum. The dorsal light reflex improved from a 45° vertical deviation following nerve crush to 4.5° by week 16. Initial predator-prey interactions were exclusively mediated by the control eye. As regeneration progressed, there was a gradual expansion of the visual field. The reaction distance and attack angles within the visual field of the experimental eye were initially less than controls, however, these differences disappeared by week 10. Improvements in visual function were closely correlated with an increase of regenerating ganglion cell axons into the optic tectum indicating sufficient synaptogenesis to mediate both simple and complex visual behavior.
Acuity and contrast sensitivity of the bluegill sunfish and how they change during optic nerve regeneration
Authors: NORTHMORE D.P.M. , OH D.-J. , CELENZA M.A.
Published: September 2007

Spatial vision was studied in the bluegill sunfish,Lepomis macrochirus(9.5–14 cm standard length) to assess the limitations imposed by the optics of the eye, the retinal receptor spacing and the retinotectal projection during regeneration. Examination of images formed by the dioptric elements of the eye showed that spatial frequencies up to 29 c/° could be imaged on the retina. Cone spacing was measured in the retina of fresh, intact eyes. The spacing of rows of double cones predicted 3.4 c/° as the cutoff spatial frequency; the spacing between rows of single and double cones predicted 6.7 c/°. Contrast sensitivity functions were obtained psychophysically in normals and fish with one regenerating optic nerve. Fish were trained to orient to gratings (mean luminance = 25 cd/m2) presented to either eye. In normals, contrast sensitivity functions were similar in shape and bandwidth to those of other species, peaking at 0.4 c/° with a minimum contrast threshold of 0.03 and a cutoff at about 5 c/°, which was within the range predicted by cone spacing. Given that the optical cutoff frequency exceeds that predicted by cone spacing, it is possible that gratings could be detected by aliasing with the bluegill's regular cone mosaic. However, tests with high contrast gratings up to 15 c/° found no evidence of such detection. After crushing one optic nerve in three trained sunfish, recovery of visual avoidance, dorsal light reflex and orienting to gratings, were monitored over 315 days. At 64–69 days postcrush, responses to gratings reappeared, and within 2–5 days contrast sensitivity at low (0.15 c/°) and medium (1.0 c/°) spatial frequencies had returned to normal. At a high spatial frequency (2.93 c/°) recovery was much slower, and complete only in one fish.
The optics of the growing lungfish eye: Lens shape, focal ratio and pupillary movements inNeoceratodus forsteri(Krefft, 1870)
Authors: BAILES HELENA J. , TREZISE ANN E.O. , COLLIN SHAUN P.
Published: September 2007

Lungfish (order Dipnoi) evolved during the Devonian period and are believed to be the closest living relatives to the land vertebrates. Here we describe the previously unknown morphology of the lungfish eye in order to examine ocular adaptations present in early sarcopterygian fish. Unlike many teleosts, the Australian lungfishNeoceratodus forsteripossesses a mobile pupil with a slow pupillary response similar to amphibians. The structure of the eye changes from juvenile to adult, with both eye and lens becoming more elliptical in shape with growth. This change in structure results in a decrease in focal ratio (the distance from lens center to the retina divided by the lens radius) and increased retinal illumination in adult fish. Despite a degree of lenticular correction for spherical aberration, there is considerable variation across the lens. A re-calculation of spatial resolving power using measured focal ratios from cryosectioning reveals a low ability to discriminate fine detail. The dipnoan eye shares more features with amphibian eyes than with most teleost eyes, which may echo the visual needs of this living fossil.
Early development of eye and retina in lanternfish larvae
Authors: BOZZANO A. , PANKHURST P.M. , SABATÉS A.
Published: September 2007

The morphological characteristics of the eyes and the retinae of lanternfish larvae ofLampanyctus crocodilus,Benthosema glaciale, andMyctophum punctatumwere analyzed in pre-flexion, flexion, and post-flexion stages. Pre-flexion larvae ofL. crocodilus, the species with the shallowest depth distribution, had spherical eyes located antero-laterally on a strongly laterally-compressed head, suggesting a forward binocular visual field.B. glacialeandM. punctatumlarvae live deeper in the water column and had eyes elongated in the dorsal-ventral plane. The eyes ofB. glacialewere prominent, projecting slightly outward from a laterally-compressed head, suggesting a strongly laterally-directed visual field.M. punctaumhad stalked elongated eyes projecting from a dorso-ventrally flattened head. The eyes can be freely rotated allowing lateral, anterior and dorsally-directed vision. A prominent choroidal gland was situated beneath the ventral portion of the eye inM. punctatumandB. glaciale, while a smaller gland was present in the dorsal and ventral portions of the eye ofL. crocodilus. In pre-flexion stage larvae, the retina of all three species was differentiated with numerous rod photoreceptors in the peripheral retinal areas and fewer cone photoreceptors mainly distributed in the central retina. This distribution suggests concomitant enhancement of scotopic sensitivity in the vertical visual plane and improved photopic acuity in the lateral and forward visual directions. The concurrent development of cones and rods, as observed in the pre-flexion stage of myctophid larvae, is consistent with meeting the special demands of visual planktivory in sub-surface waters. During larval development a gradual increase of ROS length was also accompanied by a progressive loss of cones that were almost totally absent in post-flexion larvae. This can be interpreted as an adaptive response to an impending deep mesopelagic adult life.
New ice thickness maps of Filchner–Ronne Ice Shelf, Antarctica, with specific focus on grounding lines and marine ice
Authors: Lambrecht A. , Sandhäger H. , Vaughan D.G. , Mayer C.
Published: September 2007

For the Filchner–Ronne Ice Shelf we have compiled measurements of meteoric ice thickness from many institutions, and several different techniques (e.g. radar and seismic sounding) to produce an improved digital map of meteoric ice thickness. This map has high-resolution compared to previous compilations and serves to highlight small-scale geographic features (e.g. ice plains, grounding-line regions). We have also produced a map of the thickness of marine ice bodies beneath the ice shelf by using borehole density data to calibrate an ice thickness to surface-elevation relation, and then comparing maps of ice surface elevation and meteoric ice thickness to infer marine ice thickness. Due to denser data coverage and the improved density-depth relation, the resulting map is a significant improvement on its predecessors and allows insight into the glaciological context of the ice shelf, in particular, into the location of the grounding lines on the southern Ronne Ice Shelf. Here the data were supplemented with barometric determination of surface elevation, which were used to locate the grounding line position. The final delineation of the grounding line position was confirmed by reference to satellite imagery, and revealed that earlier estimates were substantially in error, especially in the area of Foundation Ice Stream and Möllereisstrom.
Political ex-prisoners and policing in transitional societies – testing the boundaries of new conceptions of citizenship and security
Authors: McKeever Gráinne , O’Rawe Mary
Published: September 2007

The article aims to test the boundaries of traditional notions and understandings of citizenship and security in transitional societies through the framing of a given question – should paramilitary ex-prisoners be allowed to join the police? The question, considered through an examination of the particular experience of Northern Ireland, acts as a springboard to the deconstruction of broader traditional and transitional assumptions around citizenship and the delivery of security in societies seeking ways out of violent conflict. The article is ultimately concerned, not so much to deliver a final answer to the specifics of the question posed in all contexts, but to problematise notions of citizenship and State to the point where broader questions need to be asked around accepted and preconceived notions of inclusivity, citizenship and security.
Enforced consociationalism and deeply divided societies: some reflections on recent developments in Fiji
Authors: Iyer Venkat
Published: September 2007

Consociationalism is seen as a useful tool in dealing with intractable ethnic, religious, linguistic and other tensions in deeply divided societies and is often preferred over federalism, partition, secession, assimilation or other forms of conflict management in such societies. This article examines the validity of many of the assumptions which underlie the concept of consociationalism by looking at the experience of its use in the Pacific island state of Fiji, which has had a long record of strife between the country’s two main ethnic groups, the indigenous Fijians and the Indo-Fijians. It argues that the consociational model – particularly one which is highly prescriptive and involves strong mandatory power-sharing – has certain structural shortcomings which make it unsuitable for adoption in societies (like Fiji) where the ethnic or other cleavages run deep. In such cases, says the author, the society concerned would do well to explore other options such as a looser form of power-sharing, proportional representation, or outright majoritarian rule but with strong minority protections. The article also examines the limitations of judicial intervention in the enforcement of consociational agreements.
Seeking gender justice in post-conflict transitions: towards a transformative women’s human rights approach
Authors: Reilly Niamh
Published: September 2007

This article critically examines the prospects for achieving a comprehensive vision of gender justice in post-conflict transitional contexts. It is divided into three main sections. The first reviews the gendered limits of mainstream approaches to transitional justice and highlights gender biases in related dominant discourses, which shape how conflict, and transitions from conflict, are understood and enacted to the detriment of women. The second focuses on the benefits and limitations of engendering wartime criminal justice with particular reference to the International Criminal Court. The third considers the prospects for a more comprehensive approach to gender justice that shifts the emphasis from ‘women as victims’ of conflict to women as agents of transformation, through an examination of the significance of Security Council Resolution 1325. Ultimately, the author argues that achieving gender justice in transitions is inextricably tied to wider bottom-up efforts by women’s movements to realise a comprehensive vision of women’s human rights within a framework of critically-interpreted, universal, indivisible human rights.
Modeling of Product Removal during Enzymatic Conversions by Using Affinity Molecules
Authors: Halsema Daniël G. R. , Janssen Anja E. M. , Boom Remko M.
Published: September 2007

The feasibility of using magnetic particles for in‐line product isolation during enzymatic conversion was studied. A comparison was made between a process based on magnetic particles and a conventional adsorption column. The enzymatic reaction was described by two consecutive first‐order reactions (synthesis and subsequent hydrolysis), while the adsorption of substrate and product was described by multicomponent Langmuir isotherms. The yield as well as synthesis/hydrolysis ratio were calculated for various system characteristics. The results show that magnetic particles are very effective when the affinity with the particles is specific and for enzymatic conversions involving low ratios of the rate of synthesis versus the rate of hydrolysis. For slow conversions and for low specific affinity molecules column separations are more appropriate.