bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of renal renin-angiotensin system in upstream stimulatory factor 2 transgenic mice
Authors: Shi Lihua , Nikolic Dejan , Liu Shu , Lu Hong , Wang Shuxia
Published: November 2008

Previously we demonstrated that upstream stimulatory factor 2 (USF2) transgenic (Tg) mice developed nephropathy including albuminuria and glomerular hypertrophy, accompanied by increased transforming growth factor (TGF)-β and fibronectin accumulation in the glomeruli. However, the mechanisms by which overexpression of USF2 induces kidney injury are unknown. USF has been shown to regulate renin expression. Moreover, the renin-angiotensin system (RAS) plays important roles in renal diseases. Therefore, in the present studies the effects of USF2 on the regulation of RAS in the kidney as well as in mesangial cells from USF2 (Tg) mice were examined. The role of USF2-mediated regulation of RAS in TGF-β production in mesangial cells was also determined. Our data demonstrate that USF2 (Tg) mice exhibit increased renin and angiotensin (ANG) II levels in the kidney. In contrast, renal expression of other components of RAS such as renin receptor, angiotensinogen, angiotensin-converting enzyme (ACE), ACE2, angiotensin type 1a (AT1a) receptor, and AT2receptor was not altered in USF2 (Tg) mice. Similarly, mesangial cells isolated from USF2 (Tg) mice had increased renin and ANG II levels. Mesangial cells overexpressing USF2 also had increased TGF-β production, which was blocked by small interfering RNA-mediated renin gene knockdown or RAS blockade (enalapril or losartan). Collectively, these results suggest that USF2 promotes renal renin expression and stimulates ANG II generation, leading to activation of the intrarenal RAS. In addition, renin-dependent ANG II generation mediates the effect of USF2 on TGF-β production in mesangial cells, which may contribute to the development of nephropathy in USF2 (Tg) mice.
Vasoconstrictor responses in the upper and lower limbs to increases in transmural pressure
Authors: Lott Mary E. J. , Hogeman Cynthia , Herr Michael , Bhagat Monica , Kunselman Allen , Sinoway Lawrence I.
Published: November 2008

The purpose of this study was to examine upper and lower limb vasoconstrictor responses to changes in transmural pressure in humans. Brachial and femoral blood mean blood velocity (MBV) and vessel diameter (Doppler ultrasound) were measured in 20 supine healthy subjects (10 men and 10 women; 27 ± 1 yr; mean ± SE) during four levels of limb suction at −25, −50, −75, and −100 mmHg, respectively. Limb suction led to an initial rise in MBV followed by a rapid fall in flow velocity to a level below MBV baseline, indicating a vasoconstriction effect. Femoral compared with brachial vessels exhibited a greater fall in flow velocity at all levels of suction (−89 ± 17 vs. −10 ± 2, −142 ± 11 vs. −14 ± 2, −156 ± 22 vs. −13 ± 2, and −162 ± 29 vs. −12 ± 2 ml/min for −25, −50, −75, and −100 mmHg, respectively; interaction effect, P < 0.05). Even at low tank suction levels (i.e., −10 and −20 mmHg), significant brachial flow velocity vasoconstriction from baseline values was demonstrated, reflecting downstream resistance vessel changes ( n = 14). Brachial and femoral diameters did not change during changes in negative tank pressure. During suction, changes in limb volumes were significantly greater in the forearm (1.4 ± 0.5%, 2.4 ± 0.8%, 3.5 ± 1.0%, and 4.3 ± 1.1%) compared with the calf (0.9 ± 0.5%, 1.4 ± 0.7%, 2.0 ± 0.8%, and 2.8 ± 1.1%) at all levels of negative tank pressures (−25, −50, −75, and −100 mmHg, respectively). Simultaneous measurements of both upper limbs and both lower limbs suggested that the majority of the reduction in flow was due to myogenic influences except when −100 mmHg of suction was applied to the lower limb. The greater vasoconstriction responses in the leg compared with the arm with suction appear to be influenced by both myogenic and sympathetic mechanisms.
Mesenteric lymph duct ligation prevents trauma/hemorrhage shock-induced cardiac contractile dysfunction
Authors: Sambol Justin T. , Lee Marlon A. , Caputo Francis J. , Kawai Kentaro , Badami Chirag , Kawai Tomoko , Deitch Edwin A. , Yatani Atsuko
Published: November 2008

Clinical and experimental studies have shown that trauma combined with hemorrhage shock (T/HS) is associated with myocardial contractile dysfunction. However, the initial events triggering the cardiac dysfunction are not fully elucidated. Thus we tested the hypothesis that factors carried in intestinal (mesenteric) lymph contribute to negative inotropic effects in rats subjected to a laparotomy (T) plus hemorrhagic shock (HS; mean arterial blood pressure of 30–40 Torr for 90 min) using a Langendorff isolated heart preparation. Left ventricular (LV) function was assessed 24 h after trauma plus sham shock (T/SS) or T/HS by recording the LV developed pressure (LVDP) and the maximal rate of LVDP rise and fall ( ± dP/d tmax) in five groups of rats: 1) naive noninstrumented rats, 2) rats subjected to T/SS, 3) rats subjected to T/HS, 4) rats subjected to T/SS with mesenteric lymph duct ligation (T/SS+LDL), or 5) rats subjected to T/HS+LDL. Cardiac function was comparable in hearts from naive, T/SS, and T/SS+LDL rats. Both LVDP and ± dP/d tmax were significantly depressed after T/HS. The T/HS hearts also manifested a blunted responsiveness to increases in coronary flow rates and Ca2+, and this was prevented by LDL preceding T/HS. Although electrocardiograms were normal under physiological conditions, when the T/HS hearts were perfused with low Ca2+ levels (∼0.5 mM), prolonged P-R intervals and second-degree plus Wenckebach-type atrioventricular blocks were observed. No such changes occurred in the control or T/HS+LDL hearts. The effects of T/HS were similar to those of the Ca2+ channel antagonist diltiazem, indicating that an impairment of cellular Ca2+ handling contributes to T/HS-induced cardiac dysfunction. In conclusion, gut-derived factors carried in mesenteric lymph are responsible for acute T/HS-induced cardiac dysfunction.
Differences between brain mass and body weight scaling to height: potential mechanism of reduced mass-specific resting energy expenditure of taller adults
Authors: Heymsfield Steven B. , Chirachariyavej Thamrong , Rhyu Im Joo , Roongpisuthipong Chulaporn , Heo Moonseong , Pietrobelli Angelo
Published: November 2008

Adult resting energy expenditure (REE) scales as height∼1.5, whereas body weight (BW) scales as height∼2. Mass-specific REE (i.e., REE/BW) is thus lower in tall subjects compared with their shorter counterparts, the mechanism of which is unknown. We evaluated the hypothesis that high-metabolic-rate brain mass scales to height with a power significantly less than that of BW, a theory that if valid would provide a potential mechanism for height-related REE effects. The hypothesis was tested by measuring brain mass on a large ( n = 372) postmortem sample of Thai men. Since brain mass-body size relations may be influenced by age, the hypothesis was secondarily explored in Thai men age ≤45 yr ( n = 299) and with brain magnetic resonance imaging (MRI) studies in Korean men ( n = 30) age ≥20<30 yr. The scaling of large body compartments was examined in a third group of Asian men living in New York (NY, n = 28) with MRI and dual-energy X-ray absorptiometry. Brain mass scaled to height with a power (mean ± SEE; 0.46 ± 0.13) significantly smaller ( P < 0.001) than that of BW scaled to height (2.36 ± 0.19) in the whole group of Thai men; brain mass/BW scaled negatively to height (−1.94 ± 0.20, P < 0.001). Similar results were observed in younger Thai men, and results for brain mass/BW vs. height were directionally the same ( P = 0.09) in Korean men. Skeletal muscle and bone scaled to height with powers similar to that of BW (i.e., ∼2–3) in the NY Asian men. Models developed using REE estimates in Thai men suggest that brain accounts for most of the REE/BW height dependency. Tall and short men thus differ in relative brain mass, but the proportions of BW as large compartments appear independent of height, observations that provide a potential mechanistic basis for related differences in REE and that have implications for the study of adult energy requirements.
Heterogenic Feedback Between Hindlimb Extensors in the Spontaneously Locomoting Premammillary Cat
Authors: Ross Kyla T. , Nichols T. Richard
Published: November 2008

Electrophysiological studies in anesthetized animals have revealed that pathways carrying force information from Golgi tendon organs in antigravity muscles mediate widespread inhibition among other antigravity muscles in the feline hindlimb. More recent evidence in paralyzed or nonparalyzed decerebrate cats has shown that some inhibitory pathways are suppressed and separate excitatory pathways from Golgi tendon organ afferents are opened on the transition from steady force production to locomotor activity. To obtain additional insight into the functions of these pathways during locomotion, we investigated the distribution of force-dependent inhibition and excitation during spontaneous locomotion and during constant force exertion in the premammillary decerebrate cat. We used four servo-controlled stretching devices to apply controlled stretches in various combinations to the gastrocnemius muscles (G), plantaris muscle (PLAN), flexor hallucis longus muscle (FHL), and quadriceps muscles (QUADS) during treadmill stepping and the crossed-extension reflex (XER). We recorded the force responses from the same muscles and were therefore able to evaluate autogenic (intramuscular) and heterogenic (intermuscular) reflexes among this set of muscles. In previous studies using the intercollicular decerebrate cat, heterogenic inhibition among QUADS, G, FHL, and PLAN was bidirectional. During treadmill stepping, heterogenic feedback from QUADS onto G and G onto PLAN and FHL remained inhibitory and was force-dependent. However, heterogenic inhibition from PLAN and FHL onto G, and from G onto QUADS, was weaker than during the XER. We propose that pathways mediating heterogenic inhibition may remain inhibitory under some forms of locomotion on a level surface but that the strengths of these pathways change to result in a proximal to distal gradient of inhibition. The potential contributions of heterogenic inhibition to interjoint coordination and limb stability are discussed.
Increased Gamma Oscillatory Activity in the Subthalamic Nucleus During Tremor in Parkinson's Disease Patients
Authors: Weinberger M. , Hutchison W. D. , Lozano A. M. , Hodaie M. , Dostrovsky J. O.
Published: November 2008

Rest tremor is one of the main symptoms in Parkinson's disease (PD), although in contrast to rigidity and akinesia, the severity of the tremor does not correlate well with the degree of dopamine deficiency or the progression of the disease. Studies suggest that akinesia in PD patients is related to abnormal increased beta (15–30 Hz) and decreased gamma (35–80 Hz) synchronous oscillatory activity in the basal ganglia. Here we investigated the dynamics of oscillatory activity in the subthalamic nucleus (STN) during tremor. We used two adjacent microelectrodes to simultaneously record neuronal firing and local field potential (LFP) activity in nine PD patients who exhibited resting tremor during functional neurosurgery. We found that neurons exhibiting oscillatory activity at tremor frequency are located in the dorsal region of STN, where neurons with beta oscillatory activity are observed, and that their activity is coherent with LFP oscillations in the beta frequency range. Interestingly, in 85% of the 58 sites examined, the LFP exhibited increased oscillatory activity in the low gamma frequency range (35–55 Hz) during periods with stronger tremor. Furthermore, in 17 of 26 cases where two LFPs were recorded simultaneously, their coherence in the gamma range increased with increased tremor. When averaged across subjects, the ratio of the beta to gamma coherence was significantly lower in periods with stronger tremor compared with periods of no or weak tremor. These results suggest that resting tremor in PD is associated with an altered balance between beta and gamma oscillations in the motor circuits of STN.
The Human Thalamic Somatic Sensory Nucleus [Ventral Caudal (Vc)] Shows Neuronal Mechanoreceptor-Like Responses to Optimal Stimuli for Peripheral Mechanoreceptors
Authors: Weiss N. , Ohara S. , Johnson K. O. , Lenz F. A.
Published: November 2008

Although the response of human cutaneous mechanoreceptors to controlled stimuli is well studied, it is not clear how these peripheral signals may be reflected in neuronal activity of the human CNS. We now test the hypothesis that individual neurons in the human thalamic principal somatic sensory nucleus [ventral caudal (Vc)] respond selectively to the optimal stimulus for one of the four mechanoreceptors. The optimal stimuli for particular mechanoreceptors were defined as follows: Pacinian corpuscles (PC), vibration at 128 Hz; rapidly adapting (RA), vibration at 32 or 64 Hz; slowly adapting type 1 (SA1), edge; slowly adapting type 2 (SA2), skin stretch. Nineteen neurons had a significant response to at least one optimal stimulus, and 17 had a significantly greater response to one stimulus than to the other three, including 7 PC-related, 7 RA-like, 3 SA1-like, and 2 SA2-like neurons. One of each of the SA1- and SA2-like thalamic neurons responded to vibration with firing rates that were lower than those to edge or stretch but not significantly. Except in the case of PC-related neurons, the receptive field (RF) sizes were larger for these thalamic neurons than for the corresponding mechanoreceptor. Von Frey thresholds were higher than those for the corresponding human RA and SA1 mechanoreceptors. These results suggest that there is a convergence of pathways transmitting input from multiple mechanoreceptors of one type on single thalamic neurons via the dorsal columns. They are also consistent with the presence of primate thalamic elements of modality and somatotopic isorepresentation.
The Dynamics of the ENSO–Atlantic Hurricane Teleconnection: ENSO-Related Changes to the North African–Asian Jet Affect Atlantic Basin Tropical Cyclogenesis
Authors: Shaman Jeffrey , Esbensen Steven K. , Maloney Eric D.
Published: November 2008

The nature of the teleconnection linking ENSO variability with Atlantic basin tropical storm formation is investigated. Solutions of the linearized barotropic vorticity equation forced with August–October El Niño event divergence produce upper-tropospheric vorticity anomalies over the Sahel and at the mouth of the North African–Asian (NAA) jet over the tropical Atlantic. These responses are similar in magnitude and orientation to observed ENSO vorticity variability for this region.

Further investigation reveals that the vorticity anomalies over the subtropical Atlantic develop primarily in response to very low wavenumber, westward-propagating stationary Rossby waves excited by El Niño–related convective activity over the equatorial Pacific Ocean. However, the dynamics of this teleconnection change as the Atlantic basin hurricane season progresses. In August and September the response is dominated by the westward-propagating stationary Rossby waves that alter vorticity within the NAA jet and to its south. The upper-tropospheric nondivergent zonal wind anomalies produced by these vorticity anomalies are similar in pattern to observed zonal wind and vertical zonal wind shear anomalies, which suppress Atlantic basin tropical cyclogenesis.

By October, eastward-propagating signals also develop over the tropical Atlantic Ocean in response to El Niño conditions. Over the main development region of Atlantic basin tropical cyclogenesis, these eastward-propagating Rossby waves appear to destructively interfere with the vorticity changes produced by the westward-propagating Rossby waves within the NAA jet. In addition, the NAA jet has shifted south by October. Consequently, the resultant upper-tropospheric nondivergent zonal wind perturbations for October are weak and suggest that ENSO should have little effect on rates of Atlantic basin tropical cyclogenesis during October. Statistical analyses of monthly ENSO-related changes in Atlantic basin tropical storm formation support this hypothesis.
Relationship between the Tibetan Snow in Spring and the East Asian Summer Monsoon in 2003: A Global and Regional Modeling Study
Authors: Seol Kyung-Hee , Hong Song-You
Published: November 2008

In 2003, a climate extreme accompanying a wet and cool summer over East Asia was recorded over the East Asian countries including central China, Korea, and Japan. A possible relation of this record-breaking summer in East Asia to above-normal snowfall over the Tibetan Plateau in spring has been investigated using the National Centers for Environmental Prediction (NCEP) global and regional models. The changes in the simulated East Asian summer monsoon circulations in response to snow anomalies over Tibet are highlighted.

The results from both global and regional model experiments suggest that above-normal snowfall over the Tibetan Plateau in May induces a weakening of the Tibetan high, which leads to the formation of favorable upper-level circulations accompanying cyclonic circulation anomalies covering the East Asian region in summer. These circulation anomalies in response to the snow anomalies over the plateau are more robust and closer to what was observed in the regional than in the global model results. The sensitivity experiments also show that the precipitation and lower-level circulation anomalies in summer, caused by the snow anomalies in spring, influence the above-normal precipitation in the lower reaches of the Yangtze River basin, as revealed in previous observational studies. However, the experiments do not fully explain the observed signals in Korea and Japan since the spring snow anomaly over Tibet plays a role in weakening the western Pacific subtropical high in the simulated summer, whereas in reality the intensity of the high was stronger than normal in 2003.
Ethnic Polarization, Ethnic Salience, and Civil War
Authors: Bhavnani Ravi , Miodownik Dan
Published: November 2008

This article examines how the relationship between ethnic polarization and civil war could be moderated by different degrees of ethnic salience. Using an agent-based computational model, we analyze the polarization—conflict relationship when ethnic salience is ``fixed''—high for every member of two nominally rival ethnic groups— and ``variable''—permitted to vary across individuals as a function of relative income. We find that (1) when salience is fixed, conflict onset is twice as high at low levels of polarization compared to when salience is permitted to vary, with the difference decreasing at high levels of polarization; (2) the relationship between conflict onset and the range over which we calculate variable salience is positive and robust for low and moderate levels of polarization; (3) the relationship between polarization and conflict onset is robust even under minority domination, if one holds salience fixed; and (4) holding ethnic salience fixed effectively amplifies the negative effect of polarization on economic performance.
The Symbiotic Division of Labour between Heterogeneous Districts in the Dutch and Italian Horticultural Industry
Authors: Belussi Fiorenza , Rita Sedita Silvia
Published: November 2008

This article focuses on the historical development of one ornamental horticulture district in the Netherlands and two in Italy. The aim is to underline the global division of labour among three districts driven by industrial district heterogeneity, uneven learning systems and a unique specialisation in production and retailing. The historical development of all the districts is very similar, but the application of science and the role of local institutions explain the evolution of the cluster in the Netherlands. Despite the lack of natural resources and unfavourable climate, high labour and energy costs, the Dutch district and the Netherlands-based horticulture industry hold a leading position. Although endowed with better natural resources, the Italian districts belong to a very weak national innovation system and are now strongly dependent on the Dutch system.
Ten New Propositions in UK Housing Macroeconomics: An Overview of the First Years of the Century
Authors: Meen Geoffrey
Published: November 2008

In the mid 1990s, Meen set out a series of propositions concerning the relationship between housing and the macro economy during the 1980s and early 1990s. This paper provides 10 further propositions for the early years of this century, taking into account recent research and policy concerns. The first five propositions concern housing market risk, whereas the remaining issues deal with the sustainability of homeownership. The empirical evidence presented finds that there is limited evidence for bubbles over the past 10 years and models of house prices are stable. Furthermore, housing possessions are unlikely to fall to the levels observed in the early 1980s. It is also suggested that the private rental market may not expand at the same rate as in the past 10 years, but there are risks to homeowners down the income distribution. Finally, the main beneficiaries of new affordability targets may be existing rather than new households.
Mercenaries, Missionaries and Misfits
Authors: Stirrat R.L.
Published: November 2008

■ The argument of the article centres around three stereotypes of the development worker: mercenary, missionary and misfit. The origins of this tripartite characterization of the aid community are unclear but certainly it has a currency, or at least a resonance, within the industry. The argument is not so much concerned with the truth or otherwise of this characterization. Rather it seeks to use these stereotypes as an entry point for exploring the tensions and contradictions in ways in which people working in the industry view themselves and others. While there are individuals who can be recognized as approximating to each of the three stereotypes, in general people veer between them, at different points in their careers and even at different points on the same day. Finally, although these three characterizations — missionary, mercenary and misfit — appear to be contrasting, this article will argue that they are in fact variations on a common theme and a modern version of what people in the industry tend to see as the new `white man's burden'.
Dueling Narratives
Authors: Davis Christine S.
Published: November 2008

This article looks at leadership in interorganizational peer-led teams: people from different backgrounds and organizations who are at comparable hierarchical levels with the leader. It also looks at the challenges of leading such a group to a new model of thinking in which the traditionally dominant frame is no longer valid. This research, reporting on observations of 118 child and family team meetings in a community children's mental health system of care, looks at the acquisition of power and leadership through team leaders' and members' use of narrative to frame and reframe meaning.
The Role of Information and Communication Technologies in the Relationship Between Group Effectiveness and Group Potency
Authors: Lira Eva M. , Ripoll Pilar , Peiró José M. , Zornoza Ana M.
Published: November 2008

The aim of this research is to examine the role of information and communication technologies in the relationship between group effectiveness and group potency changes. A laboratory experiment compared 44 groups of four members, working in two communication media—face-to-face condition and computer-mediated communication (CMC). Groups developed a project during 4 weekly meetings during a 1-month period. No significant difference in group potency between communication media was found initially. However, different patterns of group potency development over time were identified. Group potency increased in the face-to-face condition, whereas it remained stable in the CMC condition. Results showed that group effectiveness has a positive effect on group potency. CMC groups that were higher in effectiveness presented higher levels of group potency than those lower in effectiveness, whereas group potency perceived by face-to-face groups remained stable over different levels of group effectiveness.
Development of Cognitive and Affective Trust in Teams
Authors: Webber Sheila Simsarian
Published: November 2008

The present research examines the development of two dimensions of trust, cognitive and affective, in student project teams over the course of a semester. Empirical examination of the evolution of multidimensional trust and its unique antecedents was explored. The results show that early trust emerges as a one-dimensional factor early in the life span of a team; cognitive and affective trust emerge as separate components over time; unique and distinct predictors positively and negatively affect early trust, cognitive trust, and affective trust; and affective trust has a stronger positive relationship with team performance than cognitive trust.
Writing the Othered Self: Autoethnography and the Problem of Objectification in Writing About Illness and Disability
Authors: Richards Rose
Published: November 2008

The individual's experience of kidney failure, transplantation, and recovery is not as well documented as might be expected. Often it is written about by outsiders (medical practitioners, care providers, academics), whereas the insider's (patient's) expertise is occluded. This conforms to the experience of many people living with illness and disability. The rendering of people as other (not like the norm) comes at a cost to their humanity. People who are ill or disabled can themselves succumb to a way of writing that simplifies their experience and objectifies themselves. I consider what it means to tell the story of oneself against a background of illness autoethnography, my own story of growing up medicalized and living with end-stage renal disease. I identify three types of illness autoethnography, one of which creates a tension between researcher as agent and researcher as object of research, and compels the reader to constantly realign himself or herself.
Self-Care Behaviors of Spouses Caring for Significant Others With Alzheimer's Disease: The Emergence of Self-Care Worthiness as a Salient Condition
Authors: Furlong Karen E. , Wuest Judith
Published: November 2008

Little of our empirical knowledge regarding how family caregivers of persons with Alzheimer's disease (AD) manage their self-care needs is grounded in the perspectives of caregivers themselves. Using a grounded theory methodology, we explored self-care behaviors of nine spousal caregivers and developed a substantive theory of finding normalcy for self that reflects how spousal caregivers restore self-care behaviors in the context of a constant state of flux. Self-care worthiness, a new concept, emerged as a salient condition of finding normalcy. This provides a starting point for understanding self-care in spousal caregivers and illuminates the intricate process of caring for self while caring for a significant other with AD.
Activity Settings, Discourse Modes and Ways of Understanding: On the Heterogeneity of Verbal Thinking
Authors: Cubero Mercedes , de la Mata Manuel , Cubero Rosario
Published: November 2008

Various authors in the tradition of cultural psychology have analysed the idea of the existence of different ways of thinking. Several classifications about ways of thinking have been proposed, all of them referring to similar ideas. Bruner distinguishes between narrative and propositional thinking, while Scribner distinguish between theoretical and empirical or functional argumentation. Vygotsky also assumed the existence of different ways of thinking. Once the cognitive plurality and the existence of different ways of thinking has been accepted, we are left with two questions: what changes in the different ways of thinking, and why does it change? With regard to the first question, we must consider the differences in the means employed to mediate mental processes. As for the second issue, we refer to the activity settings and practices in which individuals participate. The empirical analysis is applied in the context of adult education. Individuals in the sample belong to two different levels of adult education: basic literacy and advanced literacy levels. Two different tasks are proposed: the first consists of preparing menus and the second is a classification task. Results related to the different ways of solving these tasks show a plurality of ways of thinking in individuals in the advanced group. Our data show how school experience allows the development of new ways of thinking and the adjustment of mental functioning to task demands. Heterogeneity of verbal thinking is here interpreted and discussed as a heterogeneity despite genetic hierarchy, instead of a non-genetic one or as a hierarchy of power. From this, it appears that development is not the replacement of one mode of discourse-thinking by another, but the differentiation and co-existence of different ways of thinking connected to different practices.
'Can I Be Bridesmaid?' Combining the Personal and Political in Same-Sex Weddings
Authors: Smart Carol
Published: November 2008

The availability of same-sex weddings poses a number of personal and political dilemmas for couples who decide that they wish to go through a ceremony of recognition or civil partnership. In this article I argue that British couples are acutely aware of the political ramifications of their decisions and I focus attention on the interplay between the personal and political in decisions that couples make on the types of ceremony they want. For example, some couples want very prominent, high profile weddings while others insist that same-sex couples do not need to display their relationships in public ceremonies because this merely emulates heterosexual practices. These issues are explored through qualitative interviews with same-sex couples which collected stories on 54 same-sex ceremonies held in the UK.
Online networks of student protest: the case of the living wage campaign
Authors: Biddix J. Patrick , Han Woo Park
Published: November 2008

Contemporary information and communication technologies (ICTs) have given rise to networked communities useful in organizing, coordinating, supporting and maintaining 'real life' activism. This article examines the campus living wage movement among college students in the United States to identify a networked activist community, its key components and the consequences for its members. A refinement of Howard's network ethnography approach serves as a mixed methods design strategy. A network analysis of hyperlinks revealed the structure of the network, while member interviews were used to discuss the importance of such connections. The findings revealed the importance of ICTs in maintaining a movement through the creation of an unintentional networked community in times of both mobilization and latency. Notably, the resultant network has allowed the campus living wage movement to overcome previous limitations inherit in student protest, and sustained the campus struggle through several student generations.
Study of chemical composition and heat treatment of electroless Ni–B–Tl alloy coating on AISI 316 stainless steel
Authors: Abdeli M. , Ahmadi Parvini N. , Khosroshahi R. A.
Published: November 2008

Despite having some useful properties, stainless steels suffer from lack of suitable surface hardness. In this research electroless Ni–B–Tl coating was used with the aim to increase their surface hardness. The effects of nickel chloride, sodium borohydride, thallium nitrate and ethylenediamine on chemical composition of coating were studied. To achieve an increase in hardness, the effects of heat treatment on the hardness of the deposited layer at various temperatures were also studied. The results showed that the deposition rate and surface hardness of the deposited layer are affected by the variation in concentration of bath components. The microstructure of the electroless Ni–B–Tl coating consists of nickel and super saturated solid solutions. It was also found that the hardness of the coating was increased due to the formation of Ni2B and Ni3B phases during heat treatment.
Mechanical and microstructural characterisations of NiCrCoAlYTa coatings on superalloys deposited by detonation gun technique
Authors: Kamal S. , Jayaganthan R. , Prakash S.
Published: November 2008

The microstructure and mechanical properties of detonation gun sprayed NiCoCrAlYTa alloy coatings on the selected superalloys were investigated. The coatings were characterised in relation to thickness, porosity, microhardness, microstructure, compositions, and phases across by using the techniques such as optical microscopy, X-ray diffraction, field emission scanning electron microscopy/energy dispersive analysis and X-ray mapping. The formation of spherical or elliptical shaped dendritic splats was observed in the as sprayed coatings on the superalloys. The splat morphology of the coatings is due to the deposition and re-solidification of successive molten or semimolten powder particles. The coatings showed a bond strength of 50 MPa and the surface roughness (arithmetic average height) of the coatings was found to be in the range of 6·25–7·48 μm. The porosity and microhardness of the coatings were less than 0·48% and 385–748 Hv respectively. The XRD analysis of the coatings showed the phases γ-Ni or γ′-Ni3Al and β-NiAl inter metallic as the minor phase.
Influence of CH3SO3H and AlCl3 in direct and pulse current electrodeposition of trivalent chromium
Authors: Mohan S. , Vijayakumar J. , Saravanan G.
Published: November 2008

Comparison of direct and pulse current electrodeposition of the trivalent chromium from urea formic acid as a complexing agent was studied in detail. The influences of CH3SO3H and AlCl3 on the properties of the deposit were also studied. The presence of CH3SO3H exhibits higher current efficiency and better corrosion resistance because of its higher hydrogen overpotential. The pulse current electrodeposition leads to growth of β-Cr. The corrosion studies were conducted by potentiodynamic polarisation and electrochemical impedance spectroscopy. The morphology of the deposits was characterised by scanning electron microscopy (SEM) and X-ray diffraction.
Allo-immune Thrombocytopaenia
Authors: Witters Ingrid , Devlieger Roland , Fryns Jean-Pierre
Published: November 2008

This case report describes the prenatal diagnosis of an intracranial haemorrhage due to allo-immune thrombocytopaenia (AITP) with HPA-1b incompatibility. In this family, a previous child had died neonatally with a presumed diagnosis of schizencephaly. Severe open-lip schizencephaly can be difficult to differentiate from destructive brain lesions due to intracranial haemorrhage, but a correct diagnosis is important due to the high recurrence risk and more severe manifestations in subsequent pregnancies with AITP.
Mcl-1 expression predicts progression-free survival in chronic lymphocytic leukemia patients treated with pentostatin, cyclophosphamide, and rituximab
Authors: Awan Farrukh T. , Kay Neil E. , Davis Melanie E. , Wu Wenting , Geyer Susan M. , Leung Nelson , Jelinek Diane F. , Tschumper Renee C. , Secreto Charla R. , Lin Thomas S. , Grever Michael R. , Shanafelt Tait D. , Zent Clive S. , Call Timothy G. , Heerema Nyla A. , Lozanski Gerard , Byrd John C. , Lucas David M.
Published: November 2008

Myeloid cell leukemia-1 (Mcl-1) is an antiapoptotic member of the Bcl-2 protein family. Increased Mcl-1 expression is associated with failure to achieve remission after treatment with fludarabine and chlorambucil in patients with chronic lymphocytic leukemia (CLL). However, the influence of Mcl-1 expression has not been examined in CLL trials using chemoimmunotherapy. We investigated Mcl-1 protein expression prospectively as part of a phase 2 study evaluating the efficacy of pentostatin, cyclophosphamide, and rituximab in patients with untreated CLL. No significant difference by Mcl-1 expression was noted in pretreatment or response parameters. However, in patients with higher Mcl-1 expression, both minimal residual disease-negative status and progression-free survival was found to be significantly reduced (57% vs 19%, P = .01; 50.8 vs 18.7 months; P = .02; respectively). Mcl-1 expression may therefore be useful in predicting poor response to chemoimmunotherapy. These findings further support pursuing treatment strategies targeting this important antiapoptotic protein. (Because the trials described were conducted before the requirement to register them was implemented, they are not registered in a clinical trial database.)
Salmonellainduces death of CD8α+ dendritic cells but not CD11cintCD11b+ inflammatory cells in vivo via MyD88 and TNFR1
Authors: Sundquist Malin , Wick Mary Jo
Published: November 2008

Dendritic cells (DCs), whose lifespan influences their ability to stimulate the immune system, are potent APCs that are critical for initiating immunity. Here, we show that oral infection with Salmonella enterica serovar Typhimurium induces death of DCs in the gut-draining lymph nodes. Although CD8α+ DCs were sensitive to Salmonella-induced death, CD8α– DCs and in particular recruited CD11cintCD11b+ inflammatory cells, were resistant. Infecting mice deficient for MyD88 revealed that Salmonella-induced death of CD8α+ DCs was dependent on this adaptor for TLR signaling. In addition, CD8α+ DCs in infected, TNFR1-deficient mice were resistant to Salmonella-induced death. These data, combined with the strict MyD88-dependent production of TNF in Salmonella-infected mice, suggest that MyD88-dependent TNF mediates DC death. As recruited CD11cintCD11b+ cells were resistant to Salmonella-induced death, they could compensate for the infection-induced loss of DCs if they function as APCs. However, in contrast to DCs, CD11cintCD11b+ cells could not present the model antigen OVA expressed in Salmonella to OVA-specific CD4 T cells. These results show that Salmonella induces DC death after oral infection via MyD88 and TNFR1, which could have a negative impact on the initiation of antibacterial immunity.
PTK7 recruits dsh to regulate neural crest migration
Authors: Shnitsar Iryna , Borchers Annette
Published: November 2008

PTK7 regulates planar cell polarity (PCP) signaling during vertebrate neural tube closure and establishment of inner ear hair cell polarity;however, its signaling mechanism is unknown. Here, we demonstrate a new function for PTK7 in Xenopus neural crest migration and use this system in combination with in vitro assays to define the intersection of PTK7 with the non-canonical Wnt signaling pathway that regulates PCP. In vitro,using Xenopus ectodermal explants, we show that PTK7 recruits dishevelled (dsh) to the plasma membrane, a function that is dependent on the PDZ domain of dsh, as well as on the conserved kinase domain of PTK7. Furthermore, endogenous PTK7 is required for frizzled7-mediated dsh localization. Immunoprecipitation experiments confirm that PTK7 can be found in a complex with dsh and frizzled7, suggesting that it cooperates with frizzled to localize dsh. To evaluate the in vivo relevance of the PTK7-mediated dsh localization, we analyzed Xenopus neural crest migration, as loss-of-function of PTK7 inhibits neural crest migration in whole embryos as well as in transplanted neural crest cells. Supporting the in vivo role of PTK7 in the localization of dsh, a PTK7 deletion construct deficient in dsh binding inhibits neural crest migration. Furthermore, the PTK7-mediated membrane localization of a dsh deletion mutant lacking PCP activity inhibits neural crest migration. Thus, PTK7 regulates neural crest migration by recruiting dsh, providing molecular evidence of how PTK7 intersects with the PCP signaling pathway to regulate vertebrate cell movements.
Mammalian Tead proteins regulate cell proliferation and contact inhibition as transcriptional mediators of Hippo signaling
Authors: Ota Mitsunori , Sasaki Hiroshi
Published: November 2008

Regulation of organ size is important for development and tissue homeostasis. In Drosophila, Hippo signaling controls organ size by regulating the activity of a TEAD transcription factor, Scalloped, through modulation of its co-activator protein Yki. Here, we show that mouse Tead proteins regulate cell proliferation by mediating Hippo signaling. In NIH3T3 cells, cell density and Hippo signaling regulated the activity of endogenous Tead proteins by modulating nuclear localization of a Yki homolog, Yap1, and the resulting change in Tead activity altered cell proliferation. Tead2-VP16 mimicked Yap1 overexpression, including increased cell proliferation, reduced cell death, promotion of EMT, lack of cell contact inhibition and promotion of tumor formation. Growth-promoting activities of various Yap1 mutants correlated with their Tead-co-activator activities. Tead2-VP16 and Yap1 regulated largely overlapping sets of genes. However, only a few of the Tead/Yap1-regulated genes in NIH3T3 cells were affected in Tead1-/-;Tead2-/- or Yap1-/- embryos. Most of the previously identified Yap1-regulated genes were not affected in NIH3T3 cells or mutant mice. In embryos, levels of nuclear Yap1 and Tead1 varied depending on cell type. Strong nuclear accumulation of Yap1 and Tead1 were seen in myocardium,correlating with requirements of Tead1 for proliferation. However,their distribution did not always correlate with proliferation. Taken together, mammalian Tead proteins regulate cell proliferation and contact inhibition as a transcriptional mediator of Hippo signaling, but the mechanisms by which Tead/Yap1 regulate cell proliferation differ depending on the cell type, and Tead, Yap1 and Hippo signaling may play multiple roles in mouse embryos.
Dual requirement for Pax6 in retinal progenitor cells
Authors: Oron-Karni Varda , Farhy Chen , Elgart Michael , Marquardt Till , Remizova Lena , Yaron Orly , Xie Qing , Cvekl Ales , Ashery-Padan Ruth
Published: November 2008

Throughout the developing central nervous system, pre-patterning of the ventricular zone into discrete neural progenitor domains is one of the predominant strategies used to produce neuronal diversity in a spatially coordinated manner. In the retina, neurogenesis proceeds in an intricate chronological and spatial sequence, yet it remains unclear whether retinal progenitor cells (RPCs) display intrinsic heterogeneity at any given time point. Here, we performed a detailed study of RPC fate upon temporally and spatially confined inactivation of Pax6. Timed genetic removal of Pax6 appeared to unmask a cryptic divergence of RPCs into qualitatively divergent progenitor pools. In the more peripheral RPCs under normal circumstances, Pax6 seemed to prevent premature activation of a photoreceptor-differentiation pathway by suppressing expression of the transcription factor Crx. More centrally, Pax6 contributed to the execution of the comprehensive potential of RPCs: Pax6 ablation resulted in the exclusive generation of amacrine interneurons. Together, these data suggest an intricate dual role for Pax6 in retinal neurogenesis, while pointing to the cryptic divergence of RPCs into distinct progenitor pools.
Two-step selection of a single R8 photoreceptor: a bistable loop betweensenselessandroughlocks in R8 fate
Authors: Pepple Kathryn L. , Atkins Mardelle , Venken Koen , Wellnitz Kari , Harding Mark , Frankfort Benjamin , Mardon Graeme
Published: November 2008

Patterning of sensory organs requires precise regulation of neural induction and repression. The neurocrystalline pattern of the adult Drosophila compound eye is generated by ordered selection of single founder photoreceptors (R8s) for each unit eye or ommatidium. R8 selection requires mechanisms that restrict R8 potential to a single cell from within a group of cells expressing the proneural gene atonal (ato). One model of R8 selection suggests that R8 precursors are selected from a three-cell `R8 equivalence group' through repression of ato by the homeodomain transcription factor Rough (Ro). A second model proposes that lateral inhibition is sufficient to select a single R8 from an equipotent group of cells called the intermediate group (IG). Here, we provide new evidence that lateral inhibition, but not ro, is required for the initial selection of a single R8 precursor. We show that in romutants, ectopic R8s develop from R2,5 photoreceptor precursors independently of ectopic Ato and hours after normal R8s are specified. We also show that Ro directly represses the R8 specific zinc-finger transcription factor senseless (sens) in the developing R2,5 precursors to block ectopic R8 differentiation. Our results support a new model for R8 selection in which lateral inhibition establishes a transient pattern of selected R8s that is permanently reinforced by a repressive bistable loop between sens and ro. This model provides new insight into the strategies that allow successful integration of a repressive patterning signal, such as lateral inhibition, with continued developmental plasticity during retinal differentiation.
Cross-repressive interactions betweenLrig3and netrin 1 shape the architecture of the inner ear
Authors: Abraira Victoria E. , del Rio Tony , Tucker Andrew F. , Slonimsky John , Keirnes Hannah L. , Goodrich Lisa V.
Published: November 2008

The sense of balance depends on the intricate architecture of the inner ear, which contains three semicircular canals used to detect motion of the head in space. Changes in the shape of even one canal cause drastic behavioral deficits, highlighting the need to understand the cellular and molecular events that ensure perfect formation of this precise structure. During development, the canals are sculpted from pouches that grow out of a simple ball of epithelium, the otic vesicle. A key event is the fusion of two opposing epithelial walls in the center of each pouch, thereby creating a hollow canal. During the course of a gene trap mutagenesis screen to find new genes required for canal morphogenesis, we discovered that the Ig superfamily protein Lrig3 is necessary for lateral canal development. We show that this phenotype is due to ectopic expression of the axon guidance molecule netrin 1(Ntn1), which regulates basal lamina integrity in the fusion plate. Through a series of genetic experiments, we show that mutually antagonistic interactions between Lrig3 and Ntn1 create complementary expression domains that define the future shape of the lateral canal. Remarkably, removal of one copy of Ntn1 from Lrig3 mutants rescues both the circling behavior and the canal malformation. Thus, the Lrig3/Ntn1feedback loop dictates when and where basement membrane breakdown occurs during canal development, revealing a new mechanism of complex tissue morphogenesis.
The influence of port shape on gas pulsations in a screw compressor discharge chamber
Authors: Mujic E , Kovacevic A , Stosic N , Smith I K
Published: November 2008

Gas pulsations in suction and discharge chambers are a significant source of noise in screw compressors. This paper shows how such effects in the discharge chamber are influenced both by the compressor operating conditions and its geometric characteristics. An area function is identified for the discharge port as an important parameter influencing the gas pulsations and it is shown how their amplitude can be reduced by optimization of the port shape.