bluuebunny/crossref_metadata_2025 huggingface dataset:
Learning development and study support an embedded approach through communities of practice
Authors: Shreeve Alison
Published: October 2007

This article argues for an approach to student support for learning based within the course rather than being solely the responsibility of separate study support units. Although recognizing the importance of such specialist support for individual students, within the current climate
in UK education with more students from diverse educational experiences, the responsibility for facilitating study must lie with all tutors. This, it is argued, can be achieved through providing more inclusive participation in learning activities where students are encouraged to undertake
responsibilities with the tutors acting as facilitators or guides. Such activities as writing project briefs, organizing learning activities and assessing are normally undertaken by tutors and many students fail to develop an understanding about the work they are required to do in art and
design. By viewing learning activities as a community of practice, where more experienced practitioner tutors enable students to participate, they are more likely to develop an identity of belonging, with an associated sense of the meaning of activities within the community of practice in
education. This is illustrated through a case study where students organized a project to participate in an international textiles trade fair. The case study is analysed through Wenger's (1998) ideas about the identity of participation.
Reconsidering Spanish nationalism, regionalism, and the centre-periphery model in the post-Francoist period, 19751992
Authors: Stapell Hamilton M
Published: October 2007

Out of a desire to prompt a reconsideration of Spanish nationalism and regionalism in the post-Francoist period, this article seeks to use the example of Madrid to expose the inadequacies of the widely accepted centre-periphery model that is often used to explain geographical identity formation in the period after 1975. Contrary to this model, which posits regional identities forming in response to a strong national centre, an examination of Madrid finds no evidence of a unified national identity, or Spanishness, articulated in the capital during this period. At the same time, there is evidence to suggest that the local and regional administrations of Madrid articulated their own regionalist project between 1979 and 1986, which implies a more global process that escapes the constraints of the centre-periphery model of identity formation and points to the creation of a multiple, or postmodern, democratic identity after the dictatorship.
How has the Portuguese innovation capability evolved? Estimating a time series of the stock of technological knowledge (19602001)
Authors: Teixeira Aurora Amlia Castro
Published: October 2007

The importance of promoting innovation has been elevated up to a status of official standard since the Lisbon European Summit in 2000. Here research and development (R&D) has been singled out as an essential element of the foundation on which innovation could be built. R&D has
been a growing area of investigation namely at level of firms micro studies aimed at uncovering firms' innovation capability. At the macro level, the relevance of R&D for countries' innovation capability has been, in a dynamic perspective, more often presumed rather than effectively tested.
This latter limitation is, to a large extent, explained by the paucity of aggregated continuous time series on innovation indicators specifically those based on R&D expenditures. This paper aims at filling this gap by providing an estimate of the Portuguese innovation capability over the
two last four decades based on the accumulated R&D efforts. Such indicator, albeit preliminary, will desirably endorse new investigation on the Portuguese catching-up process and, in this way, might inform present and future public programs related to R&D policies in particular and
innovation policies in general.
Families in Europe
Authors: Torres Anlia , Mendes Rita , Lapa Tiago
Published: October 2007

Analysing data from European Social Survey in this article we try to capture the main features of the European families. Accounting for the changing trends of the last 40 years in family arrangements, practices and values we discuss some theoretical and methodological issues raised by the exercise of comparing countries also. General configurations like family's size, composition of the households, living arrangements and marital status are identified and analysed clustering European countries. The insertion of men and women on the labour market, fertility rates and the hours of work of parents are also other central focus of discussion. Our results tend to contradict some stereotypes. The majority of Europeans are formally married or living together, conjugal disruption being transitory for divorced and the separated tend to return to conjugality. With modern ideals, family is, for all European countries and with very similar averages, the most valued dimension of personal life.
The Avant-Garde and Modern Sovereignty. By Way of Introduction
Authors: Bru Sascha , Keunen Bart
Published: October 2007

To thee alone is given a growth and a development depending on thine own free will. Thou bearest in thee the germs of a universal life. Pico della Mirandola, Speech on the Dignity of Man (1487)
Militant Politics and Avant-garde Performance Art in the Early Futurist Movement
Authors: Berghaus Günter
Published: October 2007

Published and archival documents in Italian archives reveal how Marinetti sought to fuse art and life in order to foster an action-oriented (rather than reflective) artistic practice. Of particular interest is the Futurist political engagement in Anarchist and Syndicalist circles, and the impact of this on Futurist artistic practices in the 1910s. Selected examples from the theatrical genres of Serate and Public Actions and their relation to the beaux gestes libertaires of the Anarchist movement illustrate why the self-proclaimed Anarchist avant-garde and Futurism could not join forces in order to activate a country deeply steeped in traditionalism. Paradoxically, Futurism dealt more successfully with the bourgeoisie than with the revolutionary Left.
Dada as Politics
Authors: Bru Sascha
Published: October 2007

European Dada can be read as a political force in its own right. A stubborn contradiction has been at work in Dada studies: European Dada has been institutionally framed with models derived from the socially relatively stable late nineteenth century, but consensus also has it that Dada emerged in times of instability and contingency. The cultural instability of Zurich and Berlin forced Dada, and Richard Huelsenbeck in particular, to operate in a sphere that was both literary and political. The texts and poetics of Dada reveal its cultural project: to reclaim literature's social status in times of extreme politicisation.
How to Do Things With Poems Performativity in the Poetry of C.P. Cavafy
Authors: Boletsi Maria
Published: October 2007

The theory of the performative – in its initial version by J.L. Austin and in its poststructuralist revisions – allows us to explore speech acts within C.P. Cavafy's poem as well as how his poems themselves can function as performatives. Performativity in these poems functions along four interrelated planes of performance, all of which are central to Cavafy's poetry: the erotic, the theatrical/public, the historical, and the linguistic. Recurring instances of “infelicitous” performatives in Cavafy's poems, especially unkept promises, reveal the critical and creative potential of this infelicity. The repeated failures and communicative gaps in the poems nevertheless work towards a notion of a felicitous poetic event, in which failure is transformed into a critical act and a motivating force for practices of constant revaluation.
Istanbul, 1945 Erich Auerbach's Philology of Extremity
Authors: Pourciau Sarah
Published: October 2007

Erich Auerbach's Mimesis has a profoundly pessimistic conclusion. The present paper takes seriously the consequences of the apocalyptic rhetoric therein introduced for Auerbach's humanist historicist project, arguing that Auerbach holds responsible his own brand of secular humanism – whose story his book tells and whose method it implements – for the “Nivellierungseffekt” he so clearly deplores. As an exile on the outskirts of European space and time (Istanbul, 1945), Auerbach possesses a privileged philological perspective from which to synthesize a history nearing its end; the techniques he employs in order to do so, however, are for him complicit in the destruction. The final chapter of Mimesis, so often considered a weak point of the work, provides a condensed and lyrical account of this predicament.
The Neural Coding of Stimulus Intensity: Linking the Population Response of Mechanoreceptive Afferents with Psychophysical Behavior
Authors: Muniak Michael A. , Ray Supratim , Hsiao Steven S. , Dammann J. Frank , Bensmaia Sliman J.
Published: October 2007

How specific aspects of a stimulus are encoded at different stages of neural processing is a critical question in sensory neuroscience. In the present study, we investigated the neural code underlying the perception of stimulus intensity in the somatosensory system. We first characterized the responses of SA1 (slowly adapting type 1), RA (rapidly adapting), and PC (Pacinian) afferents of macaque monkeys to sinusoidal, diharmonic, and bandpass noise stimuli. We then had human subjects rate the perceived intensity of a subset of these stimuli. On the basis of these neurophysiological and psychophysical measurements, we evaluated a series of hypotheses about which aspect(s) of the neural activity evoked at the somatosensory periphery account for perception. We evaluated three types of neural codes. The first consisted of population codes based on the firing rate of neurons located directly under the probe. The second included population codes based on the firing rate of the entire population of active neurons. The third included codes based on the number of active afferents. We found that the response evoked in the localized population is logarithmic with stimulus amplitude (given a constant frequency composition), whereas the population response across all neurons is linear with stimulus amplitude. We conclude that stimulus intensity is best accounted for by the firing rate evoked in afferents located under or near the locus of stimulation, weighted by afferent type.
Cannabinoids Elicit Antidepressant-Like Behavior and Activate Serotonergic Neurons through the Medial Prefrontal Cortex
Authors: Bambico Francis Rodriguez , Katz Noam , Debonnel Guy , Gobbi Gabriella
Published: October 2007

Preclinical and clinical studies show that cannabis modulates mood and possesses antidepressant-like properties, mediated by the agonistic activity of cannabinoids on central CB1receptors (CB1Rs). The action of CB1R agonists on the serotonin (5-HT) system, the major transmitter system involved in mood control and implicated in the mechanism of action of antidepressants, remains however poorly understood. In this study, we demonstrated that, at low doses, the CB1R agonist WIN55,212-2 [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)]pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-naphthalenyl) methanone mesylate] exerts potent antidepressant-like properties in the rat forced-swim test (FST). This effect is CB1R dependent because it was blocked by the CB1R antagonist rimonabant and is 5-HT mediated because it was abolished by pretreatment with the 5-HT-depleting agent parachlorophenylalanine. Then, usingin vivoelectrophysiology, we showed that low doses of WIN55,212-2 dose dependently enhanced dorsal raphe nucleus 5-HT neuronal activity through a CB1R-dependent mechanism. Conversely, high doses of WIN55,212-2 were ineffective in the FST and decreased 5-HT neuronal activity through a CB1R-independent mechanism. The CB1R agonist-induced enhancement of 5-HT neuronal activity was abolished by total or medial prefrontocortical, but not by lateral prefrontocortical, transection. Furthermore, 5-HT neuronal activity was enhanced by the local microinjection of WIN55,212-2 into the ventromedial prefrontal cortex (mPFCv) but not by the local microinjection of WIN55,212-2 into the lateral prefrontal cortex. Similarly, the microinjection of WIN55,212-2 into the mPFCv produced a CB1R-dependent antidepressant-like effect in the FST. These results demonstrate that CB1R agonists possess antidepressant-like properties and modulate 5-HT neuronal activity via the mPFCv.
Efferent Association Pathways from the Rostral Prefrontal Cortex in the Macaque Monkey
Authors: Petrides Michael , Pandya Deepak N.
Published: October 2007

The different prefrontal cortical regions exert executive control over processing occurring in posterior cortical regions. We examined with the autoradiographic method, in the macaque monkey, the course and terminations of the efferent corticocortical connections of the rostral prefrontal region, the function of which is least understood. Three efferent streams of fibers organized into three distinct fasciculi convey rostral prefrontal influences on posterior cortical areas. These connections provide powerful insights into the cortical regions on which executive control is being exercised. The lateral stream of fibers via the extreme capsule targets the midsection of the auditory superior temporal region and the multisensory areas of the superior temporal sulcus, thus permitting control over the most integrated aspects of cognitive processing. The fibers coursing through the extreme capsule originating in areas 10 and 9 continue as part of the white matter of the superior temporal gyrus (i.e., the middle longitudinal fasciculus) to target the midportion of the superior temporal gyrus (areas TAa, TS2, and TS3) and adjacent multisensory area TPO within the upper bank of the superior temporal sulcus. Some of the fibers from areas 10 and 9 that enter the extreme capsule terminate in the ventral part of the insula. The dorsomedial limbic stream via the cingulate fasciculus targets the anterior and posterior cingulate cortex, as well as the retrosplenial cortex, allowing control over motivational and memory processes. A ventral limbic stream via the uncinate fasciculus targets the temporal proisocortex and the amygdala, indicating an additional powerful influence over the emotional motivational sphere.
Developmental Expression of Ca2+-Permeable AMPA Receptors Underlies Depolarization-Induced Long-Term Depression at Mossy Fiber–CA3 Pyramid Synapses
Authors: Ho Michelle T.-W. , Pelkey Kenneth A. , Topolnik Lisa , Petralia Ronald S. , Takamiya Kogo , Xia Jun , Huganir Richard L. , Lacaille Jean-Claude , McBain Chris J.
Published: October 2007

Many central excitatory synapses undergo developmental alterations in the molecular and biophysical characteristics of postsynaptic ionotropic glutamate receptors via changes in subunit composition. Concerning AMPA receptors (AMPARs), glutamate receptor 2 subunit (GluR2)-containing, Ca2+-impermeable AMPARs (CI-AMPARs) prevail at synapses between mature principal neurons; however, accumulating evidence indicates that GluR2-lacking, Ca2+-permeable AMPARs (CP-AMPARs) contribute at these synapses early in development. Here, we used a combination of imaging and electrophysiological recording techniques to investigate potential roles for CP-AMPARs at developing hippocampal mossy fiber–CA3 pyramidal cell (MF–PYR) synapses. We found that transmission at nascent MF–PYR synapses is mediated by a mixed population of CP- and CI-AMPARs as evidenced by polyamine-dependent inwardly rectifying current–voltage (I–V) relationships, and partial philanthotoxin sensitivity of synaptic events. CP-AMPAR expression at MF–PYR synapses is transient, being limited to the first 3 postnatal weeks. Moreover, the expression of CP-AMPARs is regulated by the PDZ (postsynaptic density-95/Discs large/zona occludens-1) domain-containing protein interacting with C kinase 1 (PICK1), because MF–PYR synapses in young PICK1 knock-out mice are philanthotoxin insensitive with linearI–Vrelationships. Strikingly, MF–PYR transmission via CP-AMPARs is selectively depressed during depolarization-induced long-term depression (DiLTD), a postsynaptic form of MF–PYR plasticity observed only at young MF–PYR synapses. The selective depression of CP-AMPARs during DiLTD was evident as a loss of postsynaptic CP-AMPAR-mediated Ca2+transients in PYR spines and reduced rectification of MF–PYR synaptic currents. Preferential targeting of CP-AMPARs during DiLTD is further supported by a lack of DiLTD in young PICK1 knock-out mice. Together, these findings indicate that the transient participation of CP-AMPARs at young MF–PYR synapses dictates the developmental window to observe DiLTD.
A Common System for the Comprehension and Production of Narrative Speech
Authors: Awad Malaka , Warren Jane E. , Scott Sophie K. , Turkheimer Federico E. , Wise Richard J. S.
Published: October 2007

Humans devote much time to the exchange of memories within the context of shared general and personal semantic knowledge. Our hypothesis was that functional imaging in normal subjects would demonstrate the convergence of speech comprehension and production on high-order heteromodal and amodal cortical areas implicated in declarative memory functions. Activity independent of speech phase (that is, comprehension and production) was most evident in the left and right lateral anterior temporal cortex. Significant activity was also observed in the posterior cortex, ventral to the angular gyri. The left and right hippocampus and adjacent inferior temporal cortex were active during speech comprehension, compatible with mnemonic encoding of narrative information, but activity was significantly less during the overt memory retrieval associated with speech production. Therefore, although clinical studies suggest that hippocampal function is necessary for the retrieval as well as the encoding of memories, the former appears to depend on much less net synaptic activity. In contrast, the retrosplenial/posterior cingulate cortex and the parahippocampal area, which are closely associated anatomically with the hippocampus, were equally active during both speech comprehension and production. The results demonstrate why a severe and persistent inability both to understand and produce meaningful speech in the absence of an impairment to process linguistic forms is usually only observed after bilateral, and particularly anterior, destruction of the temporal lobes, and emphasize the importance of retrosplenial/posterior cingulate cortex, an area known to be affected early in the course of Alzheimer's disease, in the processing of memories during communication.
Language Learning and the Politics of Belonging: Sudanese Women RefugeesBecomingandBeing“American”
Authors: Warriner Doris S.
Published: October 2007

In this article, I explore the complicated relationship between ideologies of language and language learning, discourses of immigration and belonging, and the actual lived experiences of individual language learners. The analysis demonstrates how questions of educational access, economic stability, and social membership are all influenced by a range of social, political, and historical factors, particularly for recently arrived immigrants and refugees from war‐torn African contexts.
Diaspora and the Anthropology of Latino Education: Challenges, Affinities, and Intersections
Authors: Villenas Sofia A.
Published: October 2007

In this article, I highlight the challenges, tensions, and affinities between Latino educational anthropology and diaspora studies. Some of the urgent questions include attention to new Latino destinations, transnationalism, and Latino diversity. It concludes by suggesting future pathways through Latina feminist thought.
Asian American History Forum: Introduction
Authors: NGAI MAE M.
Published: October 2007

This introduction considers the ways that the following articles by Erika Lee, Dorothy Fujita-Rony, Judy Tzu-Chun Wu, and Paul Spickard contribute to new directions in the study of Asian American history and transnationalism.
The “Yellow Peril” and Asian Exclusion in the Americas
Authors: LEE ERIKA
Published: October 2007

This article examines the history of Asian migration and exclusion in the Americas by focusing on the intersections of national histories, transnational migration, and the globality of race. Beginning in the mid-nineteenth century, a transnational conversation about race, migration, and national security circulated throughout North and South America. The subject was the global migration of Asians and the alleged threat they posed. By examining the circularity of Asian migration within the Americas as well as the transnational nature of anti-Asian racism, this article seeks to revise our understandings of transnationalism and contribute to the larger global history of race.
Channel Tunnel Rail Link section 2: Stratford
Authors: Dyson Steve , Blight Ian
Published: October 2007

The last stop before London on the Channel Tunnel Rail Link – now called High Speed 1 – is Stratford International in the heart of the London 2012 Olympic park. This paper describes the design and construction of the station box, a 1 km long, and up to 55 m wide and 26 m deep, open concrete structure. It initially served as the construction and portal site for four of the London tunnel drives on section 2 and now provides the location for the Stratford International station and major track junctions. Excavated material from both the tunnels and the box has been used to regenerate the old railway freight yards into a site for a major new development.
Channel Tunnel Rail Link section 2: St Pancras International station
Authors: Gardner Ian , Smart Tim
Published: October 2007

St Pancras International station is the jewel in the crown of the £5·8 billion Channel Tunnel Rail Link project – now known as High Speed 1. It replaces Waterloo as home for the UK Eurostar service, which now arrives in continental Europe 15 minutes quicker thanks to completion of the final second section of the project. This paper describes its design and construction, which included a painstaking refurbishment and extension of the 140 year old Barlow-designed train shed as well as creation of new state-of-the-art international station facilities.
Channel Tunnel Rail Link section 2: railway systems
Authors: Bennett David
Published: October 2007

Building Britain's first main-line railway for over a century – and one carrying trains at an unprecedented 300 km/h – required a completely new set of design standards for railway systems. This paper describes the signalling, trackwork and diverse range of other mechanical and electrical systems which, together with the rolling stock, make the tunnels, earthworks and structures of the second section of the Channel Tunnel Rail Link – now renamed High Speed 1 – into a transport system.
Channel Tunnel Rail Link section 2: designing a safe, high-speed railway
Authors: Watson Keith
Published: October 2007

Safety has been at the heart of the design of the Channel Tunnel Rail Link project – now know as High Speed 1 – but perhaps nowhere more so than in the complex section 2 of the route, more than half of which is in tunnel. This paper describes how the design and layout of the 39 km second section was heavily influenced by safety considerations, particularly the design and spacing of the cross-passages between running tunnels, the tunnel ventilation systems and the emergency response procedures.
Inhibition of NADPH Oxidase Prevents Advanced Glycation End Product–Mediated Damage in Diabetic Nephropathy Through a Protein Kinase C-α–Dependent Pathway
Authors: Thallas-Bonke Vicki , Thorpe Suzanne R. , Coughlan Melinda T. , Fukami Kei , Yap Felicia Y.T. , Sourris Karly C. , Penfold Sally A. , Bach Leon A. , Cooper Mark E. , Forbes Josephine M.
Published: October 2007

OBJECTIVE—Excessive production of reactive oxygen species (ROS) via NADPH oxidase has been implicated in the pathogenesis of diabetic nephropathy. Since NADPH oxidase activation is closely linked to other putative pathways, its interaction with changes in protein kinase C (PKC) and increased advanced glycation was examined.

RESEARCH DESIGN AND METHODS—Streptozotocin-induced diabetic or nondiabetic Sprague Dawley rats were followed for 32 weeks, with groups randomized to no treatment or the NADPH oxidase assembly inhibitor apocynin (15 mg · kg−1 · day−1; weeks 16–32). Complementary in vitro studies were performed in which primary rat mesangial cells, in the presence and absence of advanced glycation end products (AGEs)-BSA, were treated with either apocynin or the PKC-α inhibitor Ro-32-0432.

RESULTS—Apocynin attenuated diabetes-associated increases in albuminuria and glomerulosclerosis. Circulating, renal cytosolic, and skin collagen–associated AGE levels in diabetic rats were not reduced by apocynin. Diabetes-induced translocation of PKC, specifically PKC-α to renal membranes, was associated with increased NADPH-dependent superoxide production and elevated renal, serum, and urinary vascular endothelial growth factor (VEGF) concentrations. In both diabetic rodents and in AGE-treated mesangial cells, blockade of NADPH oxidase or PKC-α attenuated cytosolic superoxide and PKC activation and increased VEGF. Finally, renal extracellular matrix accumulation of fibronectin and collagen IV was decreased by apocynin.

CONCLUSIONS—In the context of these and previous findings by our group, we conclude that activation of NADPH oxidase via phosphorylation of PKC-α is downstream of the AGE–receptor for AGE interaction in diabetic renal disease and may provide a novel therapeutic target for diabetic nephropathy.
Partial Pancreatectomy in Adult Humans Does Not Provoke β-Cell Regeneration
Authors: Menge Bjoern A. , Tannapfel Andrea , Belyaev Orlin , Drescher Robert , Müller Christophe , Uhl Waldemar , Schmidt Wolfgang E. , Meier Juris J.
Published: October 2007

OBJECTIVE—β-Cell regeneration has been proposed as a possible treatment for diabetes, but the capacity for new β-cell formation in humans is yet unclear. In young rats, partial pancreatectomy prompts new β-cell formation to restore β-cell mass. We addressed the following questions: In adult humans: 1) Does partial pancreatectomy provoke new β-cell formation and increased β-cell mass? 2) Is β-cell turnover increased after partial pancreatectomy?

RESEARCH DESIGN AND METHODS—Protocol 1: human pancreatic tissue was collected from 13 patients who underwent two consecutive partial pancreas resections, and markers of cell turnover were determined in both tissue samples, respectively. Protocol 2: pancreas volumes were determined from abdominal computer tomography scans, performed in 17 patients on two separate occasions after partial pancreatectomy.

RESULTS—Protocol 1: fasting glucose concentrations increased significantly after the 50% pancreatectomy (P = 0.01), but the fractional β-cell area of the pancreas remained unchanged (P = 0.11). β-Cell proliferation, the overall replication index (Ki67 staining), and the percentage of duct cells expressing insulin were similar before and after the partial pancreatectomy. The overall frequency of apoptosis (terminal deoxynucleotidyl transferase biotin-dUTP nick-end labeling) was slightly increased following the partial pancreatectomy (P = 0.02). Protocol 2: pancreatic volume was ∼50% reduced to 35.6 ± 2.6 ccm3 by the partial pancreatectomy. The total pancreatic volume was unchanged after an interval of 247 ± 160 days (35.4 ± 2.7 ccm3; P = 0.51).

CONCLUSIONS—Unlike in rodents, a 50% pancreatectomy does not prompt β-cell regeneration in adult humans. This explains the high incidence of diabetes after pancreatic resections. Such differences in β-cell turnover between rodents and humans should be born in mind when evaluating new treatment options aiming to restore β-cell mass in patients with diabetes.
Exercise Stress Testing in Patients With Type 2 Diabetes: When Are Asymptomatic Patients Screened?
Authors: Harris George D. , White Russell D.
Published: October 2007

IN BRIEF

There are no evidence-based guidelines for screening asymptomatic diabetic patients for coronary artery disease (CAD). One well-studied screening tool is exercise treadmill testing. Many diabetic patients with no symptoms of CAD have abnormal stress tests. For asymptomatic patients, identification of cardiovascular risk factors and risk stratification may help physicians justify the performance of treadmill evaluation. Patients considering moderate or vigorous exercise and those at highest risk can undergo exercise stress testing with referral for further evaluation as indicated. For patients with decreased exercise capacity, inability to reach target heart rates, or absence of chest pain during exercise, stress nuclear imaging may be more valuable than exercise electrocardiograph testing.
Excess turbulence as a cause of turbohypobiosis in cultivation of microorganisms
Authors: Rikmanis Maris , Berzinš Andrejs , Viesturs Uldis
Published: October 2007

The present review describes the influence of different types of mixing systems under excess turbulence conditions on microorganisms. Turbohypobiosis phenomena were described by applying a method for measurement of the kinetic energy of flow fluctuations based on the piezoeffect. It can be assumed that the shear stress effect (the state of turbohypobiosis) plays a role mainly when alternative mechanisms in cells cannot ensure a normal physiological state under stress conditions. Practically any system (inner construction of a bioreactor, culture and cultivation conditions, including mixing) requires its own optimisation to achieve the final goal, namely, the maximum product and/or biomass yields from substrate (YP/S or/and YX/S), respectively. Data on the biotechnological performance of cultivation as well as power input, kinetic energy (e) of flow fluctuations, air consumption rate, rotational speed, tip speed, etc. do not correlate directly if the mixing systems (impellers-baffles) are dissimilar. Even the widely used specific power consumption cannot be relied upon for scaling up the cultivation performance using dissimilar mixing systems. A biochemical explanation for substrate and product transport via cell walls, carbon pathways, energy generation and utilisation, etc. furnishes insight into cellular interactions with turbulence of different origin for different types of microorganisms (single cells, mycelia forming cells, etc.).
Proteomics of RNA polymerase II holoenzymes during P19 cardiomyogenesis
Authors: Maes Olivier
Published: October 2007

The embryonal carcinoma P19 model has allowed the elucidation of a role for several transcription factors in cell differentiation. Here, the regulation of the RNA polymerase II machinery has been explored through its association with multifunctional complexes involved in transcription. An interaction proteomics analysis of TFIIS-purified RNA polymerase II (RNAPII) holoenzymes during cardiomyogenesis is described. Modifications of protein complexes that may be associated with transcriptionally active and activator responsive RNAPII holoenzymes were detected in a serum and DMSO dependent manner. Subunits of the PAF1 and Mediator complexes were correlated with holoenzymes from non-differentiated and terminally differentiated P19 cultures respectively. Moreover, high levels of nucleolin were identified in all forms of holoenzymes by two-dimensional gel electrophoresis, and suggest that nucleolin could bind to RNAPII and TFIIS. Several proteins that were identified in the RNAPII holoenzymes are known to have functions in mRNA processing and may bind to nucleolin. A novel function for nucleolin is proposed as a possible pivotal platform between transcription, mRNA processing and export.
Welfare Reforms and Consumption among Single Mother Households: Evidence from Canadian Provinces
Authors: Brzozowski Matthew
Published: October 2007

This paper evaluates the impact of the 1995_1998 Ontario welfare reforms on the consumption levels of single mothers. I compare changes in after-tax income and in total expenditure among Ontario single mothers to those among three distinct segments of the Canadian population: single mothers in Quebec and British Columbia, single women with no children in Ontario, and married couples with children in Ontario. The comparison with demographically identical groups under different provincial administrations, and the implementation of propensity score matching of difference-in-difference estimates, sets my approach apart from similar research conducted using US data. The results indicate an initial decrease in the relative consumption levels among Ontario single mothers. This negative policy impact is not present in the long-term results.
Performance analysis of an innovative multimode, multisalt and multieffect chemisorption refrigeration system
Authors: Li T. X. , Wang R. Z. , Oliveira R. G. , Wang L. W.
Published: October 2007

The conceptual design of an innovative multimode, multisalt and multieffect solid‐gas chemisorption refrigeration system with evaporation and resorption processes is presented. In the proposed system, both the evaporation heat of the refrigerant during adsorption process and the reaction heat of the low‐temperature salt during resorption process are employed to provide useful cooling. The reaction heat of the high‐temperature salt is recovered for the regeneration process of the middle temperature salt. The presented system has the distinct advantage of larger cooling capacity per unit of heat input in comparison with other types of sorption refrigeration systems, based exclusively on evaporation or resorption. To identify the expected COP of the proposed system, two groups of working pairs containing metal chlorides and ammonia were analyzed. The ideal coefficient of performance (COP) can be improved by more than 59 to 169% if compared to the COP obtained with other kinds of cycle. When the sensible heats of the reactant, the refrigerant and the metallic part of the reactors are considered in the calculation of the COP, this figure can reach values between 0.91 and 1.80, according to the salts employed and the mass ratio between the metallic part of the reactor and the salt. © 2007 American Institute of Chemical Engineers AIChE J, 2007
A new generation of fibers from alginic acid for dressing materials
Authors: Mikołajczyk Teresa , Wołowska‐Czapnik Dorota , Boguń Maciej
Published: October 2007

We developed and elaborated manufacturing conditions for the production of alginic acid fibers with high sorption properties. The fibers' tenacity obtained at a level of 16 cN/tex is suitable for textile processing these fibers, and will make it possible to produce a new generation of highly absorptive dressing materials. The presence of acid groups in the fiber‐forming material allows us to use them for the addition of new generation antibiotics, which makes it possible to extend the antibacterial effects of these fibers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Is there a hormonal network in Tetrahymena? A systematic investigation of hormonal effects on the hormone content
Authors: Csaba G. , Pállinger Éva
Published: October 2007

The effect of six hormones (histamine, serotonin, insulin, epidermal growth factor (EGF), oxytocin and gonadotropin) was studied on the hormone (histamine, serotonin, adrenocorticotropic hormone [ACTH], endorphin and triiodothyronine [T3]) content of Tetrahymena. The hormones were given in 10−9 or 10−12 M concentrations or as 0.1 and 0.001 I.U. ml−1 (in the case of oxytocin and gonadotropin) for 1 h. The hormones in picomolar concentration, i.e. at levels which can be present also in natural conditions, influence the amount of other hormones inside the cell. Their effect is not a general one: it is individual, the level of one of the hormones was elevated, while that of the others diminished under the effect of the same hormonal stimulus. Insulin was the only hormone, which influenced the concentration of other hormones in one direction, elevating them. This effect could have a role in the life‐saving property of this hormone in Tetrahymena, but the hormones were not studied from this point of view. Usually there is no difference between the effect of the two concentrations used, but there are situations when the effect of the two concentrations is opposite. This means that there is a possible concentration dependence and this could influence differently the cells which are far from or near to the secretor cell. Considering earlier observations, the duration of the treatment can also influence the result. The results give new data to the hormonal regulation at unicellular level (which can be the base of regulation at higher evolutionary levels) and point to the possibility of a hormonal network. Copyright © 2007 John Wiley & Sons, Ltd.
Detection of a Pathway From Linoleate to a Novel Cyclopentenone: cis‐12‐Oxo‐10‐Phytoenoic Acid in Sunflower Roots
Authors: Grechkin Alexander N. , Ogorodnikova Anna V. , Gnezdilov Oleg I. , Mukhtarova Lucia S.
Published: October 2007

The lipoxygenase pathway in sunflower roots was studied in vitro. A preliminary incubation of linoleic acid with 15 000 g supernatant of homogenate of sunflower roots (1.5–6 days after germination) revealed the predominant activity of 13‐lipoxygenase. The exogenously added linoleic acid 13‐hydroperoxide is further utilized through two competing pathways. One of them is directed towards formation of the ketodiene (9Z,11E)‐13‐oxooctadeca‐9,11‐dienoic acid. The second pathway, which is controlled by allene oxide synthase, leads to the formation of an α‐ketol and a novel cyclopentenone, rac‐cis‐12‐oxo‐10‐phytoenoic acid (12‐oxo‐PEA) via a short‐lived allene oxide. Unexpectedly, the cyclopentenone 12‐oxo‐PEA is the predominant allene oxide synthase product. Identification of cis‐12‐oxo‐PEA was confirmed by its UV, mass, 1H NMR and 2D‐COSY spectral data. The highest yield of 12‐oxo‐PEA is observed in very young roots (1.5–2 days after germination). The results of methanol‐trapping experiments demonstrate that both 12‐oxo‐PEA and α‐ketol are formed through the unstable allene oxide intermediate, (9Z)‐12,13‐epoxyoctadeca‐9,11‐dienoic acid, which is the primary product of allene oxide synthase. Since 12‐oxo‐PEA is a jasmonate congener, its biosynthesis in plants might be of physiological importance.
Antibody Labeling of Cholesterol/Ceramide Ordered Domains in Cell Membranes
Authors: Scheffer Luana , Futerman Anthony H. , Addadi Lia
Published: October 2007

A monoclonal antibody raised against mixed monolayers of 60:40 mol % cholesterol/C16‐ceramide of known structure was used to label cholesterol/ceramide‐rich domains in cell membranes. The antibody, Cer–Chol 405F specifically recognizes the mixed crystalline and homogeneous phase in monolayers, but it does not interact with either of the components separately. It interacts differently with mixed monolayers that contain ceramides of different acyl chain length. When used on cells, the antibody labeling is sensitive to changes in cholesterol and ceramide levels, as well as to over‐expression of specific ceramides; this is in agreement with the results that were obtained on lipid monolayers. This represents a proof of concept of the applicability of a new approach to the structural characterization of lipid microdomains in cell membranes. The approach consists of raising antibodies that recognize specific structural organizations of lipids in artificial mixtures, characterizing the antibody/ordered domain complexes in vitro, and subsequently using them to detect the presence of the same (or similar) domains in cell membranes.
In Situ Synthesis of Gold and Silver Nanoparticles by Using Redox‐Active Amphiphiles and Their Phase Transfer to Organic Solvents
Authors: Si Satyabrata , Dinda Enakshi , Mandal Tarun K.
Published: October 2007

An in situ reduction approach to synthesizing gold and silver nanoparticles by using a series of newly designed, redox‐active amphiphiles at basic pH is described. These amphiphiles are the conjugates of a fatty acid (e.g., oleic acid, stearic acid, and lauric acid) and a redox‐active amino acid (e.g., tryptophan or tyrosine). The amphiphile‐coated nanoparticles are then efficiently transferred from water to different nonpolar organic media (such as benzene, toluene, xylene, cyclohexane, and hexane) simply by acid treatment. The phase‐transfer process was monitored by UV/visible spectroscopy and transmission electron microscopy, and the results showed that the average particle size and size distribution remain almost unchanged after transferring to the organic media. The anchoring of the amphiphile to the nanoparticle surface was confirmed by FTIR spectroscopy and thermogravimetric analysis. A mechanism is proposed to describe the stability of colloidal Au and Ag nanoparticles formed in situ and their phase transfer to organic solvents. The presence of the amphiphile increases the thermal stability of the colloidal gold nanoparticle conjugates in organic solvents.
A Nanoporous Reactor for Efficient Proteolysis
Authors: Qiao Liang , Liu Yun , Hudson Sarah P. , Yang Pengyuan , Magner Edmond , Liu Baohong
Published: October 2007

A nanoreactor based on mesoporous silicates is described for efficient tryptic digestion of proteins within the mesochannels. Cyano‐functionalized mesoporous silicate (CNS), with an average pore diameter of 18 nm, is a good support for trypsin, with rapid in situ digestion of the model proteins, cytochrome c and myoglobin. The generated peptides were analyzed by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS). Proteolysis by trypsin‐CNS is much more efficient than in‐solution digestion, which can be attributed to nanoscopic confinement and concentration enrichment of the substrate within the mesopores. Proteins at concentrations of 2 ng μL−1 were successfully identified after digestion for 20 min. A biological complex sample extracted from the cytoplasm of human liver tissue was digested by using the CNS‐based reactor. Coupled with reverse‐phase HPLC and MALDI‐TOF MS/MS, 165 proteins were identified after standard protein data searching. This nanoreactor combines the advantages of short digestion time with retention of enzymatic activity, providing a promising way to advance the development of proteomics.
A Molecular Shuttle for Driving a Multilevel Fluorescence Switch
Authors: Zhou Weidong , Li Junbo , He Xiaorong , Li Cuihong , Lv Jing , Li Yuliang , Wang Shu , Liu Huibiao , Zhu Daoben
Published: October 2007

A [2]rotaxane‐based molecular shuttle comprised a macrocycle mechanically interlocked to a chemical “dumbbell” has been prepared in high yields by a thermodynamically controlled, template‐induced clipping procedure. This molecular shuttle has two different recognition sites, namely, NH2+ and amide, separated by a phenyl unit. The macrocycle exhibits high selectivity for the NH2+ recognition sites in the protonated form through noncovalent interactions, which include 1) N+H⋅⋅⋅O hydrogen bonds; 2) CH⋅⋅⋅O interactions between the CH2NH2+CH2 protons on the thread and the oligo(ethylene glycol) unit in the macrocycle; 3) π⋅⋅⋅π stacking interaction between macrocycle and aromatic unit. Upon deprotonation of the [2]rotaxane the macrocycle glides to the amide recognition site due to the hydrogen bonds between the CONH group and the oligo(ethylene glycol) unit in the macrocycle. The deprotonation process requires about 10 equivalents of base (iPr2NEt) in polar acetone, while the amount of base is only 1.2 equivalents in apolar tetrachloroethane. Upon addition of Li+, the conformation of the [2]rotaxane was altered as a result of the collective interactions of 1) hydrogen bonds between pyridine nitrogen and amide hydrogen atoms; 2) coordination between the oligo(ethylene glycol) unit, amide oxygen atom and Li+ cation. Then, when Zn2+ ions are added, the macrocycle returns to the deprotonated NH recognition site owing to coordination of the macrocycle and NH from the axle with the Zn2+ ion. All the above‐mentioned movement processes are reversible through the alternate addition of TFA/iPr2NEt, Li/[12]‐crown‐4 and Zn2+/ethylenediaminetetraacetate (EDTA), by virtue of hydrogen bonding and metal‐ion complexation. Significantly, the three independent movement processes are all accompanied by fluorescent responses: 1) complete repression in the protonated form; 2) low‐level expression in the deprotonated form; 3) medium‐level expression following addition of Li+; 4) high‐level expression on complexation with Zn2+.
Low serum albumin level is associated with cytomegalovirus reactivation in patients with chronic lymphoproliferative diseases treated with alemtuzumab (Campath‐1H)‐based therapies
Authors: Borthakur Gautam , Lin E , Faderl Stefan , Ferrajoli Alessandra , Wierda William , Giles Francis , Browning Mary L. , Kantarjian Hagop , Keating Michael , O'Brien Susan
Published: October 2007

BACKGROUND.

Alemtuzumab (Campath‐1H), a monoclonal antibody that targets the CD52 antigen, has been approved for the treatment of fludarabine‐refractory chronic lymphocytic leukemia. However, the profound immunosuppression caused by alemtuzumab has been associated with infectious complications.

METHODS.

The authors report on the incidence and risk factors for development of symptomatic cytomegalovirus reactivation in 113 patients with chronic lymphoproliferative disorders who received alemtuzumab‐based therapy. Kaplan‐Meier methods were applied to generate survival curves, and the log‐rank test was used to assess the difference between groups; in addition, univariate and multivariate Cox proportional hazards models were used to estimate the hazard ratio of death including 95% confidence intervals.

RESULTS.

Cytomegalovirus reactivation was diagnosed in 25 patients (22%), and most of those patients responded to antiviral therapy. Nine additional patients had asymptomatic cytomegalovirus viremia.

CONCLUSIONS.

With appropriate therapy, most patients achieved clearance of cytomegalovirus viremia. Low serum albumin was the only factor associated significantly with symptomatic cytomegalovirus reactivation. Cancer 2007. © 2007 American Cancer Society.
Does androgen‐deprivation therapy accelerate the development of frailty in older men with prostate cancer?
Authors: Bylow Kathryn , Mohile Supriya G. , Stadler Walter M. , Dale William
Published: October 2007

The majority of men with prostate cancer are aged ≥65 years. Men, as they age, are more likely to suffer from impaired physical function. The standard treatment for recurrent prostate cancer is androgen‐deprivation therapy (ADT). Well‐established toxicities from ADT include lean weight loss or sarcopenia, muscle weakness, fatigue, and reduced activity levels. Frailty is a term from geriatrics that describes older individuals with limited physiologic reserve who are at significant risk for adverse outcomes, including falls, disability, hospitalization, and death. An increasingly accepted definition of frailty is a syndrome in which ≥3 of the following are present: unintentional (lean) weight loss ≥10 pounds in the past year, weakness (measured by grip strength), slow walking speed, self‐reported exhaustion, and low physical activity. This clinical syndrome overlaps closely with the known toxicities of ADT. In addition, alterations in the inflammatory system, neuroendocrine system, and energy production are associated with this syndrome, as evidenced by biomarkers such as C‐reactive protein, interleukin‐6, and tumor necrosis factor‐α. For this article, the authors reviewed the evidence for the effect of ADT on each of the 5 frailty components plus the identified biomarkers, and the evidence indicates that ADT may accelerate the development of frailty in vulnerable older men with prostate cancer. Given the association of frailty with important clinical outcomes such as hospitalization and death, this potential consequence of ADT should be considered carefully when initiating therapy in older patients with recurrent prostate cancer. Cancer 2007. © 2007 American Cancer Society.