bluuebunny/crossref_metadata_2025 huggingface dataset:
Small‐scale disturbances spread along trophic chains: leaf‐cutting ant nests, plants, aphids, and tending ants
Authors: Farji‐Brener Alejandro G. , Gianoli Ernesto , Molina‐Montenegro Marco A.
Published: April 2008

Small‐scale disturbances caused by animals often modify soil resource availability and may also affect plant attributes. Changes in the phenotype of plants growing on disturbed, nutrient‐enriched microsites may influence the distribution and abundance of associated insects. We evaluated how the high nutrient availability generated by leaf‐cutting ant nests in a Patagonian desert steppe may spread along the trophic chain, affecting the phenotype of two thistle species, the abundance of a specialist aphid and the composition of the associated assemblage of tending ants. Plants of the thistle species Carduus nutans and Onopordum acanthium growing in piles of waste material generated by leaf‐cutting ant nests (i.e., refuse dumps) had more leaves, inflorescences and higher foliar nitrogen content than those in non‐nest soils. Overall, plants in refuse dumps showed higher abundance of aphids than plants in non‐nest soils, and aphid colonies were of greater size on O. acanthium plants than on C. nutans plants. However, only C. nutans plants showed an increase in aphid abundance when growing on refuse dumps. This resulted in a similar aphid load in both thistle species when growing on refuse dumps. Accordingly, only C. nutans showed an increase in the number of ant species attending aphids when growing on refuse dumps. The increase of soil fertility generated by leaf‐cutting ant nests can affect aphid abundance and their tending ant assemblage through its effect on plant size and quality. However, the propagation of small‐scale soil disturbances through the trophic chain may depend on the identity of the species involved.
Increasing Finance, Improving Schools
Authors: Loubert Linda
Published: April 2008

Much debate from many political sides has ensued to raise attention to the struggle state legislatures face over school finance issues. This study examines the changes in academic achievement, before and after increases in funding occur, to show that money does matter. The uniqueness of this study is that it examines per pupil funding and academic achievement test scores, Texas Assessment of Academic Skills (TAAS), not at the aggregated school district level, but at the neighborhood school level. Using data from Dallas County public schools, we are able to see that even within school districts, as resources increase, achievement improves.
Reduced hyperalgesia in homozygous carriers of a GTP cyclohydrolase 1 haplotype
Authors: Tegeder Irmgard , Adolph Jan , Schmidt Helmut , Woolf Clifford J. , Geisslinger Gerd , Lötsch Jörn
Published: April 2008

Background: Carriers of a particular haplotype of the GTP cyclohydrolase gene (GCH1) had less pain after surgery for chronic lumbar radiculopathy and a decreased sensitivity to some experimental mechanical pain stimuli. Ex‐vivo, GCH1 upregulation and BH4 productio after forskolin stimulation were reduced, while baseline BH4 concentrations were not affected. This suggested that the haplotype may mainly exert its modulating function when the GCH1 system is provoked. The present study aimed at (i) testing this hypothesis and (ii) independently reproducing the pain‐decreasing effects of a particular GCH1 haplotype having been previously associated with pain protection.

Methods: Experimental pain models with sensitization (local skin inflammation, dermal capsaicin application) and without sensitization (punctate pressure, blunt pressure, thermal and electrical pain) were assessed in 10 homozygous and 22 non‐carriers of the particular GCH1 haplotype reportedly associated with pain protection. GCH1, iNOS upregulation and BH4 production were assessed ex‐vivo in white blood cells after lipopolysaccharide stimulation for 24h.

Results: Carriers of the particular GCH1 haplotype addressed in this study had higher thresholds to punctate mechanical pain (von Frey hairs) following local skin inflammation (18.1±11.3 vs. 9±2.8g; p=0.005) and, to a lesser degree, to heat pain following capsaicin sensitization (35.2±0.9 vs. 36.6±2.4°C; p=0.026). In contrast, heat and pressure thresholds and tolerance to electrical stimulation in pain models without sensitization did not differ among the genotypes. GCH1, BH4 and iNOS upregulation in white blood cells after lipopolysaccharide stimulation were decreased in carriers of the GCH1 haplotype, which verified that the genotype groups differed with respect to regulation of the biopterin pathway.

Conclusions: This study verifies previous results that decreased GCH1 function or inducibility as a result of genetic polymorphisms protects against pain. This study extents previous results by showing that this pain protection is mainly conferred under conditions of hyperalgesia resulting from sensitization, supporting specific functions of BH4 in relation to particular aspects of pain.
Psychiatric disorders after an accident: Predictors and the influence of the psychiatric condition prior to an accident
Authors: Wrenger Marco , Lange Corinna , Langer Martin , Heuft Gereon , Burgmer Markus
Published: April 2008

Background

The goal of this study is to assess prevalence and incidence of psychiatric sequelae in a sample of inpatient accident survivors. Such an attempt to assess psychiatric conditions that originate due to an accident seems to be important; this does not include psychiatric conditions already present prior to the accident.

Method

208 accident victims were consecutively examined over a period of 12 months using DSM-IV diagnostic assessment, CAPS, and self-evaluating questionnaires as well as ISS for injury severity. A predictor model for psychiatric disorders was set up.

Results

Incidence of newly developed Axis I disorders in our sample was 14.2% (6 months) and 12.3% (12 months). Incidence of PTSD was 5.9% (6 months) and 2.5% (12 months). Comorbidity was a general phenomenon. The psychiatric condition prior to the accident could be identified as a predictor for the development of Axis I disorders. The subjectively evaluated intensity of experienced threat to life and female gender were the main predictors for the development of PTSD.

Conclusions

Accidents can lead to different psychiatric disorders. PTSD as a single diagnosis is rare. Without taking into account pre-existing disorders, the incidence may be overestimated. Two predictor models for the development of PTSD and other mental disorders are presented.
Late-Quaternary summer temperature changes in the northern-European tree-line region
Authors: Seppä Heikki , MacDonald Glen M. , Birks H. John B. , Gervais Bruce R. , Snyder Jeffrey A.
Published: April 2008

We present two new quantitative July mean temperature (Tjul) reconstructions from the Arctic tree-line region in the Kola Peninsula in north-western Russia. The reconstructions are based on fossil pollen records and cover the Younger Dryas stadial and the Holocene. The inferred temperatures are less reliable during the Younger Dryas because of the poorer fit between the fossil pollen samples and the modern samples in the calibration set than during the Holocene. The results suggest that the Younger Dryas Tjulin the region was 8.0–10.0°C, being 2.0–3.0°C lower than at present. The Holocene summer temperature maximum dates to 7500–6500 cal yr BP, with Tjulabout 1.5°C higher than at present. These new records contribute to our understanding of summer temperature changes along the northern-European tree-line region. The Holocene trends are consistent in most of the independent records from the Fennoscandian–Kola tree-line region, with the beginning of the Holocene thermal maximum no sooner than at about 8000 cal yr BP. In the few existing temperature-related records farther east in the Russian Arctic tree line, the period of highest summer temperature begins already at about 10,000 cal yr BP. This difference may reflect the strong influence of the Atlantic coastal current on the atmospheric circulation pattern and the thermal behaviour of the tree-line region on the Atlantic seaboard, and the more direct influence of the summer solar insolation on summer temperature in the region east of the Kola Peninsula.
Detection of Kobe-typeBabesia microtiassociated with Japanese human babesiosis in field rodents in central Taiwan and southeastern mainland China
Authors: SAITO-ITO A. , TAKADA N. , ISHIGURO F. , FUJITA H. , YANO Y. , MA X.-H. , CHEN E.-R.
Published: April 2008

Field rodent surveys forBabesiainfection were performed from 2002 to 2005 in the vicinities of human babesiosis occurrences in Taiwan and mainland China.Babesia microtiwas identified by microscopical examination and/or PCR in 1Rattus coxingaand 1Crocidura horsfieldiiin central Taiwan and in 13Niviventer confucianusand 1Apodemus agrariusin Zhejiang and Fujian Provinces of southeastern China. Of 15B. microtisamples detected by PCR, all except 1 were shown to be the Kobe-type, the aetiological small subunit rRNA gene-type of the first Japanese patient; the exception was also a Kobe-related type. The Kobe-type had been found in rodents only in a few places including the human infection occurrence place in Japan. The internal transcribed spacer 1 to 2 sequences of the Taiwanese and Chinese Kobe-types were very similar to each other but considerably different (approx. 94% pairwise identities) from that of the Japanese Kobe-type. A Taiwanese Kobe-type strain was serologically differentiated from the Kobe strain originating from the Japanese first patient. The distribution of the Kobe-type in the vicinities of human babesiosis occurrences in Taiwan and China as well as in Japan is suggestive of involvement of the Kobe-type in Asian human babesiosis.
Who is Isaiah's Servant? Narrative identity and theological potentiality
Authors: Gignilliat Mark
Published: April 2008

The question ‘Who is the Servant?’ is one which remains a debated topic among many interpreters of Isaiah 40–55. This article seeks to address the same question with the aid and perspective of narrative identity. Narrative identity, as explicated by Ricoeur and Frei, is a means of understanding a character within a literary plot, or real life, as displayed in a narrated sequence of events. A person's identity, especially within literature, is the constancy of the self in the tortuous events of a narrated sequence over time. This article seeks to adjudicate the question of the Servant's identity by observing the character of the Servant within the plot of Isaiah 40–55. The conclusion drawn is that the Servant is the unique means of God's reconciliation of both Zion and the nations. Also, the divine action and description of YHWH and the Servant begin to bleed in such a way that the Servant can be described as a unique member of the divine identity.
The shape of soteriology and thepistis Christoudebate
Authors: Stubbs David L.
Published: April 2008

A historic debate with great implications for theology has resurfaced in New Testament circles; however, it has not received the attention it should by theologians. It concerns how to translate and interpret approximately ten instances of the Greek phrasepistis Christouand its near equivalents in the letters of Paul. This phrase occurs within theologically crucial sections of Romans and Galatians, which have provided the foundation for the Reformation understanding of ‘justification by grace through faith’. The question is whether ‘faith’ in these phrases refers principally to the believer's ‘faith in Christ’, as traditionally understood, or should be translated and understood as ‘the faith of Christ’. In this article, I hope to introduce theologians to this debate and make a contribution to it from a theological angle, by describing the two primary ‘patterns of soteriology’ which are in play, and then examining how easily these different patterns of soteriology can be read onto what Paul writes concerning three crucial issues in his letters: salvation, the Law and the ‘righteousness of God’. I argue that the overall theological vision which includes three facets – a christologically centred understanding of thepistis Christoupassages, a broader understanding ofpistis, and the centring of soteriology around the concept of ‘participation in Christ’ – provides the most convincing interpretational matrix for reading Paul. I also point out implications this has for contemporary theology.
The soul and the reading of scripture: a note on Henri De Lubac
Authors: Ayres Lewis
Published: April 2008

Henri DeLubac's work on multi-sense scriptural reading has become a major resource for Catholic and Protestant theologians seeking a new integration of biblical studies and theology. Rarely, however, is it noticed that De Lubac's account of scriptural interpretation involves a robust notion of the soul and its transformation in the Christian life – and that in linking these themes De Lubac accurately reflects a central theme of pre-modern exegesis. This article thus suggests, first, that defending a notion of soul is important for those seeking to appropriate pre-modern exegesis. The article then argues that such a project is only possible if we move beyond Harnackian notions of early Christianity's ‘hellenisation’ and see the soul as a theological doctrine. The soul is the fundamental locus of a transformation in which Christians act in and through the Spirit as members of the body of Christ. Once the status of the soul is acknowledged, we are then best able to follow De Lubac's call for the reintegration of moral-practical aspects of Christianity and the discipline of theology. The article finally argues that Christian accounts of scriptural interpretation should find their core in an understanding of scripture as a graced resource for the formation of Christians, and that these accounts should be ever attentive to the place of scripture within the drama of salvation.
The theological function of the doctrine of the divine attributes and the divine glory, with special reference to Karl Barth and his reading of the Protestant Orthodox
Authors: Holmes Christopher R. J.
Published: April 2008

Theological discourse on the doctrine of the attributes of God has lacked a clear sense of its purpose within the doctrine of God. It has far too often led one into an abstract realm in which an incipient naturalism is present concerning who God is and what God is like: the attributes resemble those of a supreme being rather than the triune God of the gospel. If the doctrine is to perform the salutary theological work for which it is capable, it would be to its advantage to describe, as does Barth, God's attributes in terms of a series of short-hand descriptions which agree with God's enacted identity in the history of Israel as fulfilled in Jesus Christ. In doing so, Barth offers a tremendously creative re-inhabitation of the doctrine. It is creative precisely because Barth avoids many of the shortcomings of the historical shape of the doctrine, as exemplified for him in Protestant Orthodoxy's tendency toward semi-nominalism, by attending anew to the declarative and communicative character of the glory of the Lord, a glory which is inclusive of a multiplicity of perfections. The result is a rearticulation of the doctrine of the divine attributes that is truly concrete, inasmuch as it eschews not only a false apophaticism, which would deflect attention away from the resplendent contours of God's saving self-display in the economy of salvation, but also attests the extent of God's propensity to ever give of himself as he is and to evoke a form of creaturely life commensurate with his self-giving.
Why gift? Gift, gender and trinitarian relations in Milbank and Tanner
Authors: Coakley Sarah
Published: April 2008

The category of ‘gift’ has become one of the central constellating themes for discussion in recent post-modern theology. This paper (originally given as an address at the AAR meeting in Atlanta, November 2003) first sets out to explain how and why the theme has come to exercise such fascination since the original appearance of Marcel Mauss's anthropological monograph, The Gift, in 1924. It goes on to provide a critical comparison of the recent treatments of ‘gift’ in the systematic work of John Milbank and Kathryn Tanner. Arguing that questions of economic justice, inner-trinitarian relations and human gender hang together in Milbank's and Tanner's rather different approaches to ‘gift’, a critique of both authors is then essayed from this systematic perspective. Whilst Milbank's attempt to ‘ground’ the gender binary in the Trinity causes question-begging claims about gendered ‘difference’ in God, and a texture of seeming assent to economic inequalities, Tanner's obliteration of any sense of reciprocity or exchange within the divine economy veers in the opposite direction, seeking merely the suppression of difference. Returning finally to the New Testament, to the Cappadocian insistence on radical donation to the poor, and to Augustine's insistence that donum applies specifically to the Spirit, it is concluded that the patristic heritage presents a more demanding and subtle account of divine ‘gift’ and human response than is found in either of these contemporary authors, for all their insight and flair.
The acquisition of German relative clauses: A case study*
Authors: BRANDT SILKE , DIESSEL HOLGER , TOMASELLO MICHAEL
Published: April 2008

This paper investigates the development of relative clauses in the speech of one German-speaking child aged 2 ; 0 to 5 ; 0. The earliest relative clauses we found in the data occur in topicalization constructions that are only a little different from simple sentences: they contain a single proposition, express the actor prior to other participants, assert new information and often occur with main-clause word order. In the course of the development, more complex relative constructions emerge, in which the relative clause is embedded in a fully-fledged main clause. We argue that German relative clauses develop in an incremental fashion from simple non-embedded sentences that gradually evolve into complex sentence constructions.
Turkish children use morphosyntactic bootstrapping in interpreting verb meaning
Authors: GÖKSUN TILBE , KÜNTAY AYLIN C. , NAIGLES LETITIA R.
Published: April 2008

How might syntactic bootstrapping apply in Turkish, which employs inflectional morphology to indicate grammatical relations and allows argument ellipsis? We investigated whether Turkish speakers interpret constructions differently depending on the number of NPs in the sentence, the presence of accusative case marking and the causative morpheme. Data were collected from 60 child speakers and 16 adults. In an adaptation of Naigles, Gleitman & Gleitman (1993), the participants acted out sentences (6 transitive and 6 intransitive verbs in four different frames). The enactments were coded for causativity. Causative enactments increased in two-argument frames and decreased in one-argument frames, albeit to a lesser extent than previously found in English. This effect was generally stronger in children than in adults. Causative enactments increased when the accusative case marker was present. The causative morpheme yielded no increase in causative enactments. These findings highlight roles for morphological and syntactic cues in verb learning by Turkish children.
Object and action picture naming in three- and five-year-old children
Authors: MASTERSON JACKIE , DRUKS JUDIT , GALLIENNE DONNA
Published: April 2008

The objectives were to explore the often reported noun advantage in children's language acquisition using a picture naming paradigm and to explore the variables that affect picture naming performance. Participants in Experiment 1 were aged three and five years, and in Experiment 2, five years. The stimuli were action and object pictures. In Experiment 1, action pictures produced more errors than object pictures for the three-year-olds, but not the five-year-olds. A qualitative analysis of the errors revealed a somewhat different pattern of errors across age groups. In Experiment 2 there was no robust difference in accuracy for the actions and objects but naming times were longer for actions. Across both experiments, imageability was a robust predictor of object naming performance, while spoken frequency was the most important predictor of action naming. The results are discussed in terms of possible differences in the manner in which nouns and verbs are acquired.
Acquiring causatives in Taiwan Southern Min
Authors: LIN HUEI-LING , TSAY JANE S.
Published: April 2008

This case study is based on the longitudinal data of a girl (LYC, 1 ; 2–3 ; 3) acquiring Taiwan Southern Min (TSM) as her first language, and it aims to discover the overgeneralization pattern of children acquiring causatives in TSM. Among the three types of causative, the errors found in other languages are mostly with lexical causatives; however, in TSM, the errors occur with morphological and analytic causatives. Being an analytic language, TSM tends to spell out the causative meaning through morphological and analytic causatives and thus most errors occur with these two types. In contrast, lexical causatives, which contain a semantic element CAUSE, were acquired late; in the data collected (1 ; 2–3 ; 3) lexical causatives were not yet found. This case study provides evidence from TSM to show a different overgeneralization pattern.
Noun grammaticalization and determiner use in French children's speech: A gradual development with prosodic and lexical influences
Authors: BASSANO DOMINIQUE , MAILLOCHON ISABELLE , MOTTET SYLVAIN
Published: April 2008

This study investigates when and how French-learning children acquire the main grammatical constraint on the noun category, i.e. the obligatory use of a preceding determiner. Spontaneous speech samples coming from the corpora of twenty children in each of three age groups, 1 ; 8, 2 ; 6, 3 ; 3, were transcribed and coded with respect to morphosyntactic, lexical and length properties of nouns. Results indicate that noun grammaticalization is a gradual process which involves early transitional procedures, as well as an increasing diversity in the content and contexts of determiner use. In support of prosodic hypotheses, noun length effects (in favor of monosyllabic nouns) mostly occurred at 1 ; 8. Animacy effects supporting the lexical hypothesis (in favor of inanimate nouns) occurred at 2 ; 6 and 3 ; 3. We suggest that noun grammaticalization is influenced by both prosodic and lexical factors. Prosodic influences predominate in the first steps of the developmental process, while lexical influences emerge in later steps.
Multiplex PCR for differential diagnosis of emerging typhoidal pathogens directly from blood samples
Authors: ALI A. , HAQUE ABDUL , HAQUE ASMA , SARWAR Y. , MOHSIN M. , BASHIR S. , TARIQ A.
Published: April 2008

ClassicallySalmonella entericaserovar Typhi (S. Typhi) is associated with typhoid, a major health problem in developing countries. However, in recent yearsS. Paratyphi A and Vi-negative variants ofS. Typhi have emerged rapidly. We have developed a nested multiplex PCR targeting five different genes for differential diagnosis of typhoidal pathogens which has been optimized to be directly applicable on clinical blood samples. Of 42 multiplex PCR-positive blood samples, 26, nine, and two were Vi-positiveS. Typhi, Vi-negativeS. Typhi andS. Paratyphi A, respectively, and five patients were found to have mixed infection. Seventeen patients grewSalmonellafrom blood culture and the remaining 25 were positive in theSalmonella-specific PCR. Tests with several common pathogens confirmed the specificity of the assay. We conclude that the proposed multiplex PCR is rapid, sensitive and specific for the diagnosis of typhoidal pathogens directly from blood samples.
Legal Issues for Faith Schools in England and Wales
Authors: Petchey Philip
Published: April 2008

Faith schools are controversial. There is nothing new about this. State funding for the schools of the established church was historically objectionable to those who dissented from that establishment. Funding for any religious school has always been objectionable to secularists, who have increased in number and influence as society has become increasingly secular. More recently, the Muslim, Hindu and other faiths of the ethnic minorities of England and Wales have begun to utilise provisions that came into being with the Christian churches in mind. This had led to objections from those who are critical of the multicultural approach which has evolved since the Second World War as a response to extensive immigration from the New Commonwealth. This paper examines whether any of the political criticism of faith schools might give rise to legal challenges, now that rights under the European Convention on Human Rights are directly enforceable. In order fully to appreciate the legal arguments, it is necessary to have some understanding of the background. Accordingly, this paper begins by summarising the history of the matter before outlining the current position. An examination of the main criticisms of faith schools follows, and the paper concludes with consideration of a variety of legal arguments.
Gods and Services: Religious Groups and Sexual Orientation Discrimination
Authors: Sandberg Russell
Published: April 2008

Exemptions for religious groups from generally applicable laws are by no means unusual, especially in the field of discrimination law. However, exemptions from laws prohibiting discrimination on grounds of sexual orientation have proved particularly controversial. The legality of exemptions in regulations prohibiting discrimination on grounds of sexual orientation in the employment sphere has been the subject of judicial review and the scope of those exemptions has also been judicially examined. The extension to prohibit discrimination on grounds of sexual orientation in the provision of goods and services has proved controversial, and case law on the extent of the religious exemption included in the British regulations is awaited. In the meantime, a recent judicial review of the corresponding Northern Ireland regulations, which were enacted prior to the British regulations, may be illuminating.
The Public Health Nutrition workforce and its future challenges: the US experience
Authors: Haughton Betsy , George Alexa
Published: April 2008

Objectives

To describe the US public health nutrition workforce and its future social, biological and fiscal challenges.

Design

Literature review primarily for the four workforce surveys conducted since 1985 by the Association of State and Territorial Public Health Nutrition Directors.

Setting

The United States.

Subjects

Nutrition personnel working in governmental health agencies. The 1985 and 1987 subjects were personnel in full-time budgeted positions employed in governmental health agencies providing predominantly population-based services. In 1994 and 1999 subjects were both full-time and part-time, employed in or funded by governmental health agencies, and provided both direct-care and population-based services.

Results

The workforce primarily focuses on direct-care services for pregnant and breast-feeding women, infants and children. The US Department of Agriculture funds 81·7 % of full-time equivalent positions, primarily through the WIC Program (Special Supplemental Nutrition Program for Women, Infants, and Children). Of those personnel working in WIC, 45 % have at least 10 years of experience compared to over 65 % of the non-WIC workforce. Continuing education needs of the WIC and non-WIC workforces differ. The workforce is increasingly more racially/ethnically diverse and with 18·2 % speaking Spanish as a second language.

Conclusions

The future workforce will need to focus on increasing its diversity and cultural competence, and likely will need to address retirement within leadership positions. Little is known about the workforce’s capacity to address the needs of the elderly, emergency preparedness and behavioural interventions. Fiscal challenges will require evidence-based practice demonstrating both costs and impact. Little is known about the broader public health nutrition workforce beyond governmental health agencies.
Trade negotiations make strange bedfellows
Authors: DIEGO-FERNÁNDEZ MATEO
Published: April 2008

Since its creation, the GATT/WTO has experienced a vast number of changes, from being a small agreement with 23 contracting parties to becoming an international organization with 151 Members; from negotiations on a limited number of tariff reductions and general rules to embracing wider and more sensitive areas, such as agriculture, services, intellectual property and environment; and from a main-trading-powers' leadership to a wider participation and more balanced reflection of interests from both developed and developing countries alike. This article attempts to demonstrate the pragmatism of coalitions, as well as both the costs and benefits of creating or joining them in the current framework of negotiations in the Doha Round.
Defining Process Design Space for Biotech Products: Case Study of Pichia pastoris Fermentation
Authors: Harms Jean , Wang Xiangyang , Kim Tina , Yang Xiaoming , Rathore Anurag S.
Published: April 2008

The concept of “design space” has been proposed in the ICH Q8 guideline and is gaining momentum in its application in the biotech industry. It has been defined as “the multidimensional combination and interaction of input variables (e.g., material attributes) and process parameters that have been demonstrated to provide assurance of quality.” This paper presents a stepwise approach for defining process design space for a biologic product. A case study, involving P. pastoris fermentation, is presented to facilitate this. First, risk analysis via Failure Modes and Effects Analysis (FMEA) is performed to identify parameters for process characterization. Second, small‐scale models are created and qualified prior to their use in these experimental studies. Third, studies are designed using Design of Experiments (DOE) in order for the data to be amenable for use in defining the process design space. Fourth, the studies are executed and the results analyzed for decisions on the criticality of the parameters as well as on establishing process design space. For the application under consideration, it is shown that the fermentation unit operation is very robust with a wide design space and no critical operating parameters. The approach presented here is not specific to the illustrated case study. It can be extended to other biotech unit operations and processes that can be scaled down and characterized at small scale.
Development of Hydrogel‐Based Keratoprostheses: A Materials Perspective
Authors: Myung David , Duhamel Pierre‐Emile , Cochran Jennifer R. , Noolandi Jaan , Ta Christopher N. , Frank Curtis W.
Published: April 2008

Research and development of artificial corneas (keratoprostheses) in recent years have evolved from the use of rigid hydrophobic materials such as plastics and rubbers to hydrophilic, water‐swollen hydrogels engineered to support not only peripheral tissue integration but also glucose diffusion and surface epithelialization. The advent of the AlphaCor core‐and‐skirt hydrogel keratoprosthesis has paved the way for a host of new approaches based on hydrogels and other soft materials that encompass a variety of materials preparation strategies, from synthetic homopolymers and copolymers to collagen‐based bio‐copolymers and, finally, interpenetrating polymer networks. Each approach represents a unique strategy toward the same goal: to develop a new hydrogel that mimics the important properties of natural donor corneas. We provide a critical review of these approaches from a materials perspective and discuss recent experimental results. While formidable technical hurdles still need to be overcome, the rapid progress that has been made by investigators with these approaches is indicative that a synthetic donor cornea capable of surface epithelialization is now closer to becoming a clinical reality.
The 1998Mw5.7 Zhangbei‐Shangyi (China) earthquake revisited: A buried thrust fault revealed with interferometric synthetic aperture radar
Authors: Li Zhenhong , Feng Wanpeng , Xu Zhonghuai , Cross Paul , Zhang Jingfa
Published: April 2008

The 1998Mw5.7 Zhangbei‐Shangyi (China) earthquake is the largest to have occurred in northern China since the large 1976Ms7.8 Tangshan earthquake. Due to its proximity to Beijing, the capital of China, it has therefore gained a lot of attention. A great number of studies have been conducted using seismic and geodetic data, but few are able to identify conclusively the orientation of the primary fault plane for this earthquake. In this paper, two independent ERS synthetic aperture radar interferograms are used to determine precisely the location and magnitude of coseismic surface displacements (∼11 cm in the radar line of sight). Modeling the event as dislocation in an elastic half‐space suggests that the earthquake is associated with a buried shallow NNE‐SSW oriented thrust fault with a limited amount of lateral displacement, which is consistent with seismic intensity distribution and aftershock locations.
Carbon cycle perturbation and stabilization in the wake of the Triassic‐Jurassic boundary mass‐extinction event
Authors: van de Schootbrugge B. , Payne J. L. , Tomasovych A. , Pross J. , Fiebig J. , Benbrahim M. , Föllmi K. B. , Quan T. M.
Published: April 2008

The Triassic‐Jurassic boundary mass‐extinction event (T‐J; 199.6 Ma) is associated with major perturbations in the carbon cycle recorded in stable carbon isotopes. Two rapid negative isotope excursions in bulk organic carbon (δ13Corg) occur within the immediate boundary interval at multiple locations and have been linked to the outgassing of 12C‐enriched CO2 from the Central Atlantic Magmatic Province. In British Columbia, a positive δ13Corg excursion of +5‰ (Vienna Peedee belemnite (V‐PDB)) spans part or all of the subsequent Hettangian stage. Here, we examine the significance of these carbon isotope excursions as records of global carbon cycle dynamics across the T‐J boundary and test the link between carbon cycle perturbation‐stabilization and biotic extinction‐recovery patterns. A combination of δ13Corg and palynological analyses from the Late Triassic to Early Jurassic in the Mingolsheim core (Germany) suggests that organic carbon isotope variations are best explained as the result of both compositional changes in terrestrial versus marine input and disturbance and recovery patterns of major terrestrial plant groups across the T‐J boundary. A new high‐resolution δ13Ccarb record from the Val Adrara section in the Southern Alps (Italy) spanning from the uppermost Rhaetian through Lower Sinemurian does not exhibit a negative excursion at the T‐J boundary but does record a large positive δ13Ccarb excursion of +4‰ (V‐PDB) in bulk carbonate that begins at the T‐J boundary and reaches a local maximum at the Early Late Hettangian boundary. Values then gradually decrease reaching +0.5‰ at the Hettangian‐Sinemurian boundary and remain relatively constant into the Early Sinemurian. Complementary δ13Ccarb data from 4 more sections that span the Hettangian‐Sinemurian boundary support carbon cycle stabilization within the Upper Hettangian. Our analyses suggest that isotope changes in organic carbon reservoirs do not necessarily require a shift in the global exogenic carbon reservoir and that the positive excursion in the carbonate carbon isotope record is best explained as the combined result of an increase in atmospheric pCO2 leading to accelerated carbon cycling, decreased skeletal carbonate production, and increased organic carbon burial lasting several hundred thousand years. The termination of the positive inorganic carbon isotope excursion coincides with the recovery of marine skeletal carbonate producers and coeval changes in terrestrial vegetation and reflects the gradual reduction in pCO2 and the stabilization of the global carbon cycle during the Sinemurian.
Current carriers in the bifurcated tail current sheet: Ions or electrons?
Authors: Israelevich P. L. , Ershkovich A. I. , Oran R.
Published: April 2008

We have studied statistical distributions of the current density in the geomagnetic tail current sheet for different sets of local plasma parameters using Cluster data. It is shown that the electric current density calculated from 4‐point magnetic field measurements exhibits no correlation with the number flux of ions. We conclude that main current carriers in the magnetospheric system of reference are electrons.
The seasonal pCO2 cycle at 49°N/16.5°W in the northeastern Atlantic Ocean and what it tells us about biological productivity
Authors: Körtzinger A. , Send U. , Lampitt R. S. , Hartman S. , Wallace D. W. R. , Karstensen J. , Villagarcia M. G. , Llinás O. , DeGrandpre M. D.
Published: April 2008

A 2‐year record of mixed layer measurements of CO2 partial pressure (pCO2), nitrate, and other physical, chemical, and biological parameters at a time series site in the northeast Atlantic Ocean (49°N/16.5°W) is presented. The data show average undersaturation of surface waters with respect to atmospheric CO2 levels by about 40 ± 15 μatm, which gives rise to a perennial CO2 sink of 3.2 ± 1.3 mol m−2 a−1. The seasonal pCO2 cycle is characterized by a summer minimum (winter maximum), which is due to the dominance of biological forcing over physical forcing. Our data document a rapid transition from deep mixing to shallow summer stratification. At the onset of shallow stratification, up to one third of the mixed layer net community production during the productive season had already been accomplished. The combination of high prestratification productivity and rapid onset of stratification appears to have caused the observed particle flux peak early in the season. Mixed layer deepening during fall and winter reventilated CO2 from subsurface respiration of newly exported organic matter, thereby negating more than one third of the carbon drawdown by net community production in the mixed layer. Chemical signatures of both net community production and respiration are indicative of carbon overconsumption, the effects of which may be restricted, though, to the upper ocean. A comparison of the estimated net community production with satellite‐based estimates of net primary production shows fundamental discrepancies in the timing of ocean productivity.
Evolution of seismic signals and slip patterns along subduction zones: Insights from a friction lab scale experiment
Authors: Voisin Christophe , Grasso Jean‐Robert , Larose Eric , Renard François
Published: April 2008

We investigate the influence of the cumulative slip on the frictional and acoustic patterns of a lab scale subduction zone. Shallow loud earthquakes, medium depth slow, deeper silent quakes and deepest steady‐state creep are reproduced by the ageing of contact interface with cumulative displacement. The Acoustic Emission evolves with cumulative displacement and interface ageing, following a trend from strong impulsive events similar to earthquake seismic signals, to a collection of smaller amplitude and longer duration signals similar to NVT. The latter emerge as the local recollection of the unstable behaviour of the contact interface globally evolving towards the stable sliding regime.
Incensole Acetate: A Novel Neuroprotective Agent Isolated fromBoswellia Carterii
Authors: Moussaieff Arieh , Shein Na'ama A , Tsenter Jeanna , Grigoriadis Savvas , Simeonidou Constantina , Alexandrovich Alexander G , Trembovler Victoria , Ben-Neriah Yinon , Schmitz Michael L , Fiebich Bernd L , Munoz Eduardo , Mechoulam Raphael , Shohami Esther
Published: April 2008

Boswellia resin has been used as a major anti-inflammatory agent and for the healing of wounds for centuries. Incensole acetate (IA), isolated from this resin, was shown to inhibit the activation of nuclear factor-κB, a key transcription factor in the inflammatory response. We now show that IA inhibits the production of inflammatory mediators in an in vitro model system of C6 glioma and human peripheral monocytes. Given the involvement of postinjury inflammation in the pathophysiology and outcome of traumatic brain injury, we examined the effect of IA on the inflammatory process and on the recovery of neurobehavioral and cognitive functions in a mouse model of closed head injury (CHI). In the brains of post-CHI mice, IA reduced glial activation, inhibited the expression of interleukin-1β, and tumor necrosis factor-α mRNAs, and induced cell death in macrophages at the area of trauma. A mild hypothermic effect was also noted. Subsequently, IA inhibited hippocampal neurodegeneration and exerted a beneficial effect on functional outcome after CHI, indicated by reduced neurological severity scores and improved cognitive ability in an object recognition test. This study attributes the anti-inflammatory activity of Boswellia resin to IA and related cembranoid diterpenes and suggests that they may serve as novel neuroprotective agents.
Role of Cortical Spreading Depressions for Secondary Brain Damage after Traumatic Brain Injury in Mice
Authors: von Baumgarten Louisa , Trabold Raimund , Thal Serge , Back Tobias , Plesnila Nikolaus
Published: April 2008

In recent years, several studies have unequivocally shown the occurrence of cortical spreading depressions (CSDs) after stroke and traumatic brain injury (TBI) in humans. The fundamental question, however, is whether CSDs cause or result from secondary brain damage. The aim of the current study was, therefore, to investigate the role of CSDs for secondary brain damage in an experimental model of TBI. C57/BL6 mice were traumatized by controlled cortical impact. Immediately after trauma, each animal showed one heterogeneous direct current (DC) potential shift accompanied by a profound depression of electroencephalogram (EEG) amplitude, and a temporary decrease of ipsi- and contralateral regional cerebral blood flow (rCBF) suggesting bilateral CSDs. Within the next 3 h after TBI, CSDs occurred at a low frequency (0.38 CSD/h per animal, n = 7) and were accompanied by rCBF changes confined to the ipsilateral hemisphere. No significant relationship between the number of SDs and lesion size or intracranial pressure (ICP) could be detected. Even increasing the number of posttraumatic CSDs by application of KCl by more than six times did not increase ICP or contusion volume. We therefore conclude that CSDs may not contribute to posttraumatic secondary brain damage in the normally perfused and oxygenated brain.
Neural Progenitor Cells Treated with EPO Induce Angiogenesis through the Production of Vegf
Authors: Wang Lei , Chopp Michael , Gregg Sara R , Zhang Rui Lan , Teng Hua , Jiang Angela , Feng Yifan , Zhang Zheng Gang
Published: April 2008

Recombinant human erythropoietin (rhEPO) induces neurogenesis and angiogenesis. Using a coculture system of mouse brain endothelial cells (MBECs) and neural progenitor cells derived from the subventricular zone of adult mouse, we investigated the hypothesis that neural progenitor cells treated with rhEPO promote angiogenesis. Treatment of neural progenitor cells with rhEPO significantly increased their expression and secretion of vascular endothelial growth factor (VEGF) and activated phosphatidylinositol 3-kinase/Akt (PI3K/Akt) and extracellular signal-regulated kinase (ERK1/2). Selective inhibition of the Akt and ERK1/2 signaling pathways significantly attenuated the rhEPO-induced VEGF expression in neural progenitor cells. The supernatant harvested from neural progenitor cells treated with rhEPO significantly increased the capillary-like tube formation of MBECs. SU1498, a specific VEGF type-2 receptor (VEGFR2) antagonist, abolished the supernatant-enhanced angiogenesis. In addition, coculture of MBECs with neural progenitor cells treated with rhEPO substantially increased VEGFR2 mRNA and protein levels in MBECs. These in vitro results suggest that EPO enhances VEGF secretion in neural progenitor cells through activation of the PI3K/Akt and ERK1/2 signaling pathways and that neural progenitor cells treated with rhEPO upregulate VEGFR2 expression in cerebral endothelial cells, which along with VEGF secreted by neural progenitor cells promotes angiogenesis.
Magnetic Resonance Imaging Investigation of Axonal Remodeling and Angiogenesis after Embolic Stroke in Sildenafil-Treated Rats
Authors: Ding Guangliang , Jiang Quan , Li Lian , Zhang Li , Zhang Zheng Gang , Ledbetter Karyn A , Panda Swayamprava , Davarani Siamak PN , Athiraman Hemanthkumar , Li Qingjiang , Ewing James R , Chopp Michael
Published: April 2008

Interaction between angiogenesis and axonal remodeling after stroke was dynamically investigated by MRI in rats with or without sildenafil treatments. Male Wistar rats were subjected to embolic stroke and treated daily with saline ( n = 10) or with sildenafil ( n = 11) initiated at 24 h and subsequently for 7 days after onset of ischemia. T*2-weighted imaging, cerebral blood flow (CBF), and diffusion tensor imaging (DTI) measurements were performed from 24 h to 6 weeks after embolization. T*2 and fractional anisotropy (FA) maps detected angiogenesis and axonal remodeling after stroke, respectively, starting from 1 week in sildenafil-treated rats. Areas demarcated by MRI with enhanced angiogenesis, elevated local CBF, and augmented axonal remodeling were spatially and temporally matched, and FA values were significantly correlated with the corresponding CBF values ( R = 0.66, P < 4 × 10−5) at 6 weeks after stroke. Axonal projections were reorganized along the ischemic boundary after stroke. These MRI measurements, confirmed by histology, showed that sildenafil treatment simultaneously enhanced angiogenesis and axonal remodeling, which were MRI detectable starting from 1 week after stroke in rats. The spatial and temporal consistency of MRI metrics and the correlation between FA and local CBF suggest that angiogenesis, by elevating local CBF, promotes axonal remodeling after stroke.
Resistin Gene Expression in Human Adipocytes Is Not Related to Insulin Resistance
Authors: Janke Jürgen , Engeli Stefan , Gorzelniak Kerstin , Luft Friedrich C. , Sharma Arya M.
Published: April 2008

Objectives: Obesity is an important risk factor for the development of insulin resistance and type 2 diabetes. Recently, a newly described circulating hormone resistin, which is expressed primarily in adipocytes, has been shown to antagonize insulin action in mice. Resistin, therefore, has been suggested to play a role in the pathogenesis of insulin resistance.

Research Methods and Procedures: We studied the expression of the resistin gene in primary cultured human adipocytes and preadipocytes. We also examined resistin gene expression in subcutaneous abdominal adipocytes in women (n = 24) over a wide range of body weight and insulin sensitivity.

Results: Whereas resistin gene expression was barely detectable in mature adipocytes, it was highly expressed in preadipocytes. Adipogenic differentiation of preadipocytes was associated with a time‐dependent down‐regulation of resistin gene expression. There was no relationship between body weight, insulin sensitivity, or other metabolic parameters and adipocyte resistin gene expression in the clinical study.

Discussion: Together these findings do not support an important role of adipose‐tissue resistin gene expression in human insulin resistance.