bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing the distribution networks stability using distributed generation
Authors: Jurado Francisco , Carpio José
Published: February 2005

Purpose

This paper describes models of micro‐turbines and fuel cells, which can be used in stability studies.

Design/methodology/approach

The plants models derived are based on the main equations. These models are developed in the Laplace domain and transient simulation is done using a software developed based on the MATLAB package.

Findings

The micro‐source is capable of providing effective load‐following service in the distribution system. However, the results also show that the micro‐source is not an uninterruptible power supply and does not protect the load from voltage instability while in grid‐connect mode. When a micro‐turbine plant is connected to a point where it gives support to a load in fault conditions, the lower the inertia of micro‐turbine plant, the greater is the destabilizing tendency for faults in the distribution system. On the other hand, transient stability is enhanced with aid of the SOFC inverter.

Originality/value

The effects of these micro‐sources on the network performance are shown and a distribution system embedded with the micro‐sources is used as an example. Finally, transient stability and voltage stability of the system are investigated.
Decentralised coordination of facts devices for power system stability enhancement using intelligent programming
Authors: Oukati Sadegh Mahmoud , Lo K.L.
Published: February 2005

Purpose

This paper seeks to propose a systematic method to design multi fuzzy FACTS based stabilizers in a multi‐machine power system.

Design/methodology/approach

Conventional FACTS based stabilizers are decentralized controllers that adopt local measurements and operate in closed loop. To improve overall system dynamic performance, a coordinating application of FACTS based stabilizer is essential. Although, numerous researches have indicated the effectiveness and superiority of fuzzy logic controllers in comparison with the conventional linear controllers in power system application but researchers have not adequately investigated coordination of multi fuzzy controllers in multi‐machine power systems to provide optimal performance. Genetic algorithm is used to determine optimum values of controllers' parameters.

Findings

The search space of the optimisation procedure is decreased to a smaller one, design and computation time can be reduced significantly and the design process becomes more systematic.

Originality/value

A systematic method is introduced to coordinate multi fuzzy FACTS based stabilizers in multi‐machine power systems.
Discrete‐valued design optimisation of a multiple‐coil inductor for uniform surface heating
Authors: Di Barba P. , Forghani B. , Lowther D.A.
Published: February 2005

Purpose

Seeks to determine the optimal shape design of an induction heating device.

Design/methodology/approach

Presents, through a case study, the optimal shape design of a multiple coil inductor for surface heating. Resorts to a procedure of automated optimal design, based on evolutionary optimisation and processing both continuous‐valued and discrete‐valued variables.

Findings

Demonstrates that it is possible to solve the design problem routinely using an optimisation tool (OptiNet) that is built to work seamlessly with a coupled electromagnetic‐thermal simulation.

Originality/value

Every design criterion that is likely to be of interest to a designer of industrial applications can be described to the system and optimised in a reasonable time frame.
Multiphase electromagnetic stirring of low conducting liquids
Authors: Ernst R. , Perrier D. , Brun P. , Lacombe J.
Published: February 2005

Purpose

To produce a controlled stirring in a low conducting liquid thanks to a new kind of multiphase inductor.

Design/methodology/approach

An experimental pilot consisting of a cylindrical salt water pool surrounded by an innovative multiphase inductor configuration, based on the single phase asynchronous motor principle, is setup. The maximum bulk stirring velocities are measured and compared with the estimate by numerical modelling.

Findings

Shows the possibility of controlling the stirring of a low conducting liquid thanks to a multiphase inductive system. The corresponding measurement results give a significant bulk velocity of a few centimetres per second.

Practical implications

This new kind of multiphase inductor, working with a single phase induction generator, seems a promising way to produce a controlled stirring in low conducting media which cover a large range of induction applications.

Originality/value

Such an innovative inductor configuration has already been tested successfully for metal alloys stirring in the middle frequency area. In this paper, an extension of this kind of multiphase inductive system for electromagnetic stirring of low conducting liquids like electrolytes in the high frequency area is presented.
Blogs
Authors: Maxymuk John
Published: February 2005

Purpose

Due to the abundance of blog sites, which run a gamut of topics, from personal diaries to hobbies to legal matters and so on, it is desirable to know their relevance to librarianship.

Design/methodology/approach

Surveys a number of library blogs and examines the content of each with the goal of determining their value and usefulness to librarianship.

Findings

Ranging from the light‐hearted to the more serious, library blogs permit a free exchange of ideas on both general and narrowly defined library topics. Posting on blogs fosters a timely exchange of information that traditional publications cannot offer.

Originality/value

Blogs redefine how information is shared, accessed, and published and adds a new dimension to how librarians seek and provide information to users.
The hidden value of sporadic customers in e‐retailing
Authors: Joia Luiz Antonio , Sanz Paulo
Published: February 2005

Purpose

To analyze empirically the transaction profitability derived from sporadic and frequent customers in the e‐retailing sector of minor home appliances in Brazil.

Design/methodology/approach

A company's database was analyzed quantitatively to assess the transaction profitability derived from sporadic and frequent customers purchasing via the firm's digital channel, namely its web site. Besides, qualitative evidence was also collected from interviews with the main professionals involved in marketing and e‐commerce in the firm and through analysis of the company's web site and e‐mail communications with customers.

Findings

The commercial transaction profitability associated with sporadic customers can be higher than that derived from frequent purchasers.

Research limitations/implications

The study concentrated on a single company within a specific industry (minor home appliance e‐retailing) based in a specific country, namely Brazil.

Practical implications

The benefits of web consumer retention would only seem to be advantageous for digital companies that are client‐centric, which can interact with these consumers. Furthermore, the mere fact of using transactional practices, low differentiation between products and the emphasis on promotion of price on the web would seem to increase sensitivity to price on the part of the consumers, particularly those who make purchases more frequently.

Originality/value

To enable practitioners and academics to grasp fully the real value of frequent and sporadic clients, in order to allow digital companies to develop coherent strategies for them.
Corporate identity and corporate communications: the antidote to merger madness
Authors: Balmer John M.T. , Dinnie Keith
Published: February 2005

This article examines the potential relevance of corporate identity and corporate communication to the merger and acquisition process. Recent studies indicate that around 50 per cent of all mergers failed to produce the synergistic benefits that were expected of them. The authors argue that this failure rate may be attributable to the neglect of corporate identity and corporate communication issues and have identified nine reasons why mergers fail, chief among which are: the undue attention that is given to short‐term financial and legal issues to the detriment of long‐term identity and communication issues; inadequate recognition of the impact of leadership issues on identity and communication; and failure to secure the goodwill of a wide range of stakeholder groups common to both companies. The authors offer a template pertaining to corporate identity and corporate communication issues in the merger and acquisition process which they call the merger mix.
Market‐oriented new product development
Authors: Alsted Søndergaard Helle
Published: February 2005

Purpose

Aims to ascertain whether a well‐known theory within consumer research – a means‐end chain (MEC) – can be used as a catalyst to achieve market oriented product development.

Design/methodology/approach

Describes a case study, involving a Danish food manufacturer, where a MEC approach was introduced to a cross‐functional development team at two different stages of the development process.

Findings

Results show that MEC data is perceived as a good way of gaining knowledge about consumers; that the information serves well as the basis of discussions and for keeping project goals fixed. The results also indicate that MEC data are most valuable to the team in the early stages of the development process and that lack of a learning orientation may inhibit the effects of a MEC approach.

Originality/value

The MEC approach shows clear advantages for market oriented product development.
“See You Again Next Week?”
Authors: Hughes John
Published: February 2005

Suggests that student tutoring may provide a partial solution to the
high attrition rate in education plus training for 16‐18‐year‐olds in
Britain. Focuses on the Pimlico Connection – a student tutoring scheme
initiated by Imperial College, London in 1975 – in which students act as
volunteer tutors in local primary and secondary schools. Evaluates the
scheme, in which 1,300 volunteer students assisted nearly 15,000 school
pupils, and concludes that, with appropriate commercial backing,
effective management and willing participants, student tutoring has
great potential for raising schoolchildren′s aspirations.
A flexible workforce for the modern economy: the role of education and training
Authors: Pollitt David
Published: February 2005

This special issue of Education + Training looks at ways of keeping the workforce up to date and adaptable, and so capable of achieving the Government’s aims. It contains a number of précised articles exploring the relationship between employers and the world of education. It pays particular attention to the ways in which business – particularly UK business – is using education. Usual issues of Education + Training contain substantive, reflective, research‐based articles which have been subject to peer review. This special issue, in contrast, is case‐study oriented, containing vignettes of best practice.
Third‐Degree Price Discrimination, Consumption Externalities and Social Welfare
Authors: Adachi Takanori
Published: February 2005

This paper analyses monopolistic third‐degree price discrimination in the presence of consumption externalities within two separate markets. Assuming linear inverse demands, we investigate an associated change in social welfare (the sum of the consumers' surpluses and the producer's profit) with the regime change from uniform pricing to price discrimination when both markets are open under either regime. It is shown that social welfare can improve even if total output is unaffected by the regime change. Moreover, it is possible that the sum of the consumers' surpluses also increases.
HOPE AND IMPEDIMENTS IN AFRICAN ANTHROPOLOGY
Authors: Ezeh P.‐J.
Published: February 2005

Local Cultures and Local Meanings… Theory and Practice in African Studies: The 14th Annual Conference of the Pan‐African Association of Anthropologists (PAAA), 2‐6 August 2004
Arabidopsis AtSPL14, a plant‐specific SBP‐domain transcription factor, participates in plant development and sensitivity to fumonisin B1
Authors: Stone Julie M. , Liang Xinwen , Nekl Emily R. , Stiers Justin J.
Published: February 2005

The recessive Arabidopsis thalianafumonisin B1‐resistant (fbr6) mutant was identified by its ability to survive in the presence of a programmed cell death (PCD)‐inducing fungal toxin FB1. The fbr6 mutant also displays altered plant architecture in the absence of FB1, most notably elongated petioles and enhanced leaf margin serration. These phenotypes are a result of a T‐DNA insertion in the SQUAMOSA promoter binding protein (SBP) domain gene, AtSPL14. AtSPL14 encodes a plant‐specific protein with features characteristic of a transcriptional regulator, including a nuclear localization signal sequence, a plant‐specific DNA binding domain (the SBP box), and a protein interaction motif (ankyrin repeats). A transiently expressed fusion of the AtSPL14 protein to green fluorescent protein is directed to the plant nucleus. DNA sequences immediately upstream of the translation start site direct expression of the β‐glucuronidase reporter gene primarily in the vascular tissues, consistent with the phenotypes of the fbr6 mutant. AtSPL14 activates transcription in yeast, with a transactivation domain residing within the N‐terminal region of the protein. Recombinant AtSPL14 protein binds A. thaliana genomic DNA in vitro in the absence of other proteins. These results indicate that FBR6/SPL14 functions as a transcriptional regulator that plays a role not only in sensitivity to FB1, but also in the development of normal plant architecture.
Spatial control of transgene expression in rice (Oryza sativa L.) using the GAL4 enhancer trapping system
Authors: Johnson Alexander A.T. , Hibberd Julian M. , Gay Céline , Essah Pauline A. , Haseloff Jim , Tester Mark , Guiderdoni Emmanuel
Published: February 2005

We used enhancer trapping with the GAL4 transcriptional activator from yeast to obtain spatial control of transgene expression in all organs of the model monocotyledonous species rice (Oryza sativa L. cv. Nipponbare). Our T‐DNA enhancer trapping cassette consisted of two principle components: (1) the minimal promoter‐equipped gal4 gene placed adjacent to the right border, and (2) the green fluorescent protein gene (gfp) fused to the upstream activation sequence element (UAS) to which GAL4 binds and activates expression, so that gfp expression corresponds to gal4 expression. Agrobacterium‐mediated integration of the cassette into the rice genome often brings the gal4 gene under transcriptional control of local genomic enhancers and promoters, resulting in gal4/gfp expression patterns ranging in specificity from single‐cell types to constitutive expression. We produced more than 13 000 enhancer trap lines with this cassette and screened T0 adult plants (1982 lines), T1 seed (2684 lines) and T1 seedlings (2667 lines) for gfp expression. Approximately 30% of the lines produced GFP, and we identified lines with gfp expression in specific cell types of all major organs of the rice plant. Subsequently, using the GUS reporter gene (uidA), we demonstrated that UAS:geneX constructs can be transactivated in specific cell types where gal4 and gfp are expressed, thus providing an excellent system for the manipulation of gene expression and physiological function in specific cell types of rice.
The Effect of Chitosan and Bion on Resistance to Pink Snow Mould in Perennial Ryegrass and Winter Wheat
Authors: Hofgaard I. S. , Ergon Å. , Wanner L. A. , Tronsmo A. M.
Published: February 2005

The effects of chitosan on resistance to pink snow mould (Microdochium nivale) were studied in young winter wheat (Triticum aestivum L.) and perennial ryegrass (Lolium perenne L.) under controlled environmental conditions. In perennial ryegrass, the putative defence activator Bion was also tested. Resistance was measured as regrowth of plants after inoculation with M. nivale and incubation in darkness at 2°C. In winter wheat, pre‐treatment with chitosan at 1000 μg per plant increased resistance to subsequent infection by M. nivale, but this effect was less significant in a replicate experiment. Chitosan‐treated winter wheat plants expressed the gene for the pathogenesis‐related protein chitinase at higher levels than non‐treated plants. Chitinase gene expression was also stimulated by M. nivale infection in winter wheat. Perennial ryegrass pre‐treated with Bion or chitosan and inoculated with M. nivale did not display better regrowth after incubation than non‐treated, inoculated plants. Rather, regrowth was reduced in some of the Bion‐treated plants after incubation. We speculate that the cost or the mechanism of induced resistance makes Bion non‐effective in plants that are not actively growing. Bion at concentrations of 10, 100 and 1000 μg active ingredient per ml, and the highest concentration of chitosan used (2000 μg per ml) reduced in vitro growth of the pathogen, suggesting that both defence activators possess antifungal activity.
Politics Lost, Politics Transformed, Politics Colonised? Theories of the Impact of Mass Media
Authors: Street John
Published: February 2005

In recent years, there has been a substantial increase in the literature on the relationship between politics and mass media, mainly in discrete topic areas such as the impact of mass media on electoral behaviour, the emergence of new forms of political communication, or media political economy. At the same time, this diverse literature has often focused on a single general issue, typically characterised in terms of the ‘transformation’ of politics. Despite this common theme, there has been relatively little attempt to connect and compare the different approaches. Looking at the theoretical differences in the new literature on politics and mass media reveals three perspectives – pluralist, constructivist, and structuralist. These approaches have too often tacitly co-existed, instead of more competitively striving to advance knowledge in the three main topic areas above.
P‐type Proton ATPases are Involved in Intracellular Calcium and Proton Uptake in the Plant Parasite Phytomonas francai
Authors: Miranda Kildare , Vercesi Anibal E. , Catisti Rosana , De Souza Wanderley , Rodrigues Claudia O. , Docampo Roberto
Published: February 2005

Abstract. The use of digitonin to permeabilize the plasma membrane of promastigotes of Phytomonas francai allowed the identification of two non‐mitochondrial Ca2+ compartments; one sensitive to ionomycin and vanadate (neutral or alkaline), possibly the endoplasmic reticulum, and another sensitive to the combination of nigericin plus ionomycin (acidic), possibly the acidocalcisomes. A P‐type (phospho‐intermediate form) Ca2+‐ATPase activity was found to be responsible for intracellular Ca2+ transport in these cells, with no evidence of a mitochondrial Ca2+ transport activity. ATP‐driven acidification of internal compartments in cell lysates and cells mechanically permeabilized was assayed spectrophotometrically with acridine orange. This activity was inhibited by low concentrations of vanadate and digitonin, was insensitive to bafilomycin A1, and stimulated by Na+ ions. Taken together, our results indicate that P‐type ATPases are involved in intracellular Ca2+ and H+ transport in promastigotes of P. francai.
THE BIOCHEMISTRY OF PARKINSON'S DISEASE
Authors: Cookson Mark R.
Published: February 2005

▪ Abstract  Several genes have been identified for monogenic disorders that variably resemble Parkinson's disease. Dominant mutations in the gene encoding α-synuclein enhance the propensity of this protein to aggregate. As a consequence, these patients have a widespread disease with protein inclusion bodies in several brain areas. In contrast, mutations in several recessive genes (parkin, DJ-1, and PINK1) produce neuronal cell loss but generally without protein aggregation pathology. Progress has been made in understanding some of the mechanisms of toxicity: Parkin is an E3 ubiquitin ligase and DJ-1 and PINK1 appear to protect against mitochondrial damage. However, we have not yet fully resolved how the recessive genes relate to α-synuclein, or whether they represent different ways to induce a similar phenotype.
Sex-related differences in energy balance in response to caloric restriction
Authors: Valle A. , Català-Niell A. , Colom B. , García-Palmer F. J. , Oliver J. , Roca P.
Published: February 2005

Sex-related differences in energy balance were studied in young Wistar rats fed standard chow pellets either ad libitum or in restricted amounts (60% of ad libitum intake) for 100 days. Caloric intake, indirect calorimetry, organ and adipose tissue weights, energy efficiency, liver mitochondrial respiration rate, and brown adipose tissue (BAT) uncoupling protein-1 (UCP1) content were measured. Ad libitum-fed females showed greater oxygen consumption (V̇o2) and carbon dioxide production (V̇co2) and lower energy efficiency than males. Caloric restriction induced a chronic drop of V̇o2 and V̇co2 in females but not in males over the period studied. Restricted females showed a better conservation of metabolic active organ mass and a greater decrease in adipose depots than restricted males. Moreover, changes of BAT size and UCP1 content suggest that BAT may be the main cause responsible for sex differences in the response of energy balance to caloric restriction. In conclusion, our results indicate that females under caloric restriction conditions deactivate facultative thermogenesis to a greater degree than males. This ability may have obvious advantages for female survival and therefore the survival of the species when food is limiting.
Effects of sympathetic nerves and angiotensin II on renal sodium and water handling in rats with common bile duct ligature
Authors: Veelken Roland , Hilgers Karl F. , Porst Markus , Krause Holger , Hartner Andrea , Schmieder Roland E.
Published: February 2005

We tested the hypothesis that angiotensin II is likely to be mandatory for the neurogenic sodium and volume retention in cirrhotic rats with common bile duct ligature (BDL) following an acute volume load. To assess the neural control of volume homeostasis, 21 days after common BDL rats underwent volume expansion (0.9% NaCL; 10% body wt over 30 min) to decrease renal sympathetic nerve activity. Untreated animals, rats with renal denervation or pretreated with a nonhypotensive dose of an angiotensin II type 1 receptor antagonist were studied. The renal renin-angiotensin system was assessed by immunohistochemistry and RT-PCR. Rats with BDL excreted only 71 ± 4% of the administered volume load. In cirrhotic rats pretreated with an angiotensin II AT1inhibitor or after renal denervation, these values ranged significantly higher from 98 to 103% ( P < 0.05 for all comparisons). Renal sympathetic nerve activity decreases by volume expansion were impaired in BDL rats ( P < 0.05) but unaffected by angiotensin II receptor inhibition. In kidneys of BDL animals, renin mRNA was increased, and immunohistochemistry revealed increased staining for peritubular angiotensin II. Renal denervation in BDL animals reduced renin expression within 5 days to control levels. In conclusion, the impaired excretion of an acute volume load in rats with liver cirrhosis is due to effects of an increased renal sympathetic nerve activity that are likely to be dependent on intrarenal angiotensin II and renin. We speculate that similar changes may contribute to long-term volume retention in liver cirrhosis.
Calmodulin mediates norepinephrine-induced receptor-operated calcium entry in preglomerular resistance arteries
Authors: Facemire Carie S. , Arendshorst William J.
Published: February 2005

Although L-type voltage-dependent calcium channels play a major role in mediating vascular smooth muscle cell contraction in the renal vasculature, non-L-type calcium entry mechanisms represent a significant component of vasoactive agonist-induced calcium entry in these cells as well. To investigate the role of these non-voltage-dependent calcium entry pathways in the regulation of renal microvascular reactivity, we have characterized the function of store- and receptor-operated channels (SOCs and ROCs) in renal cortical interlobular arteries (ILAs) of rats. Using fura 2-loaded, microdissected ILAs, we find that the L-type channel antagonist nifedipine blocks less than half the rise in intracellular calcium concentration ([Ca2+]i) elicited by norepinephrine. SOCs were activated in these vessels using the sarco/endoplasmic reticulum Ca2+ATPase (SERCA) inhibitors cyclopiazonic acid and thapsigargin and were dose dependently blocked by the SOC antagonists Gd3+and 2-aminoethoxydiphenyl borate (2-APB) and the combined SOC/ROC antagonist SKF-96365. Gd3+had no effect on the non-L-type Ca2+entry activated by 1 μM NE. A low concentration of SKF-96365 that did not affect thapsigargin-induced store-operated Ca2+entry blocked 60–70% of the NE-induced Ca2+entry. Two different calmodulin inhibitors (W-7 and trifluoperazine) also blocked the NE-induced Ca2+entry. These data suggest that in addition to L-type channels, NE primarily activates ROCs rather than SOCs in ILAs and that this receptor-operated Ca2+entry mechanism is regulated by calmodulin. Interestingly, 2-APB completely blocked the NE-induced non-L-type Ca2+entry, implying that SOCs and ROCs in preglomerular resistance vessels share a common molecular structure.
p38 MAP kinase inhibition ameliorates cisplatin nephrotoxicity in mice
Authors: Ramesh Ganesan , Reeves W. Brian
Published: February 2005

Cisplatin is an important chemotherapeutic agent but can cause acute renal injury. Part of this acute renal injury is mediated through tumor necrosis factor-α (TNF-α). The pathway through which cisplatin mediates the production of TNF-α and injury is not known. Cisplatin activates p38 MAPK and induces apoptosis in cancer cells. p38 MAPK activation leads to increased production of TNF-α in ischemic injury and in macrophages. However, little is known concerning the role of p38 MAPK in cisplatin-induced renal injury. Therefore, we examined the effect of cisplatin on p38 MAPK activity and the role of p38 MAPK in mediating cisplatin-induced TNF-α production and renal injury. In vitro, cisplatin caused a dose-dependent activation of p38 MAPK in proximal tubule cells. Inhibition of p38 MAPK activation led to inhibition of TNF-α production. In vivo, mice treated with a single dose of cisplatin (20 mg/kg body wt) developed severe renal dysfunction at 72 h [blood urea nitrogen (BUN): 154 ± 34 mg/dl, creatinine: 1.4 ± 0.4 mg/dl], which was accompanied by an increase in kidney p38 MAPK activity and an increase in infiltrating leukocytes. However, animals treated with the p38 MAPK inhibitor SKF-86002 along with cisplatin showed less renal dysfunction (BUN: 55 ± 14 mg/dl, creatinine: 0.3 ± 0.02 mg/dl, P < 0.05), less severe histological damage, and fewer leukocytes compared with cisplatin+vehicle-treated animals. Serum levels of TNF-α, sTNFRI, and sTNFRII also increased significantly in cisplatin-treated mice compared with SKF-86002-treated mice ( P < 0.05). Kidney mRNA levels of TNF-α were significantly increased in cisplatin-treated mice compared with either SKF-86002- or saline-treated animals. The hydroxyl radical scavenger DMTU (100 mg·kg body wt−1·day−1) prevented the activation of p38 MAPK by cisplatin both in vitro and in vivo. DMTU also completely prevented cisplatin-induced renal injury (BUN: 140 ± 27 vs. 22 ± 2 mg/dl, P < 0.005) and the increase in serum TNF-α (33 ± 7 vs. 4 ± 2 pg/ml, P < 0.005) and kidney TNF-α mRNA in vivo. We conclude that hydroxyl radicals, either directly or indirectly, activate p38 MAPK and that p38 MAPK plays an important role in mediating cisplatin-induced acute renal injury and inflammation, perhaps through production of TNF-α.
Impact of postnatal glucocorticoids on early lung development
Authors: Kovar Jana , Willet Karen E. , Hislop Alison , Sly Peter D.
Published: February 2005

Inhaled glucocorticoid treatment during the first 2 yr of life is controversial because this is a period of major structural remodeling of the lung. Rabbits received aerosolized budesonide (Bud; 250 μg/ml) or injected dexamethasone (Dex; 0.05 mg·ml−1·kg−1) between 1 and 5 wk of age. Treatment with Bud caused specific growth retardation of the lung. Dex but not Bud affected the mechanical properties of the lung parenchyma, when corrected for lung volume. Small peripheral airway walls in both glucocorticoid groups were thinner and had fewer alveolar attachment points with greater distance between attachments than controls, but collagen content was not affected by glucocorticoids. Dex led to reduced body weight, lung volume, alveolar number, and surface area. The alveolar size and number and elastin content, when related to lung volume, was not affected by Bud, suggesting normal structural development but inhibition of total growth. Arterial wall thickness and diameter were affected by Bud. This study demonstrates that developing lungs are sensitive to inhaled glucocorticoids. As such, the use of glucocorticoids in young infants and children should be monitored with caution and only the lowest doses that yield significant clinical improvement should be used.
Prevailing hyperglycemia is critical in the regulation of glucose metabolism during exercise in poorly controlled alloxan-diabetic dogs
Authors: Christopher Michael J. , Rantzau Christian , McConell Glenn , Kemp Bruce E. , Alford Frank P.
Published: February 2005

The separate impacts of the chronic diabetic state and the prevailing hyperglycemia on plasma substrates and hormones, in vivo glucose turnover, and ex vivo skeletal muscle (SkM) during exercise were examined in the same six dogs before alloxan-induced diabetes (prealloxan) and after 4–5 wk of poorly controlled hyperglycemic diabetes (HGD) in the absence and presence of ∼300-min phlorizin-induced (glycosuria mediated) normoglycemia (NGD). For each treatment state, the ∼15-h-fasted dog underwent a primed continuous 150-min infusion of [3-3H]glucose, followed by a 30-min treadmill exercise test (∼65% maximal oxygen capacity), with SkM biopsies taken from the thigh (vastus lateralis) before and after exercise. In the HGD and NGD states, preexercise hepatic glucose production rose by 130 and 160%, and the metabolic clearance rate of glucose (MCRg) fell by 70 and 37%, respectively, compared with the corresponding prealloxan state, but the rates of glucose uptake into peripheral tissues (Rdtissue) and total glycolysis (GF) were unchanged, despite an increased availability of plasma free fatty acid in the NGD state. Exercise-induced increments in hepatic glucose production, Rdtissue, and plasma-derived GF were severely blunted by ∼30–50% in the NGD state, but increments in MCRg remained markedly reduced by ∼70–75% in both diabetic states. SkM intracellular glucose concentrations were significantly elevated only in the HGD state. Although Rdtissueduring exercise in the diabetic states correlated positively with preexercise plasma glucose and insulin and GF and negatively with preexercise plasma free fatty acid, stepwise regression analysis revealed that an individual's preexercise glucose and GF accounted for 88% of Rdtissueduring exercise. In conclusion, the prevailing hyperglycemia in poorly controlled diabetes is critical in maintaining a sufficient supply of plasma glucose for SkM glucose uptake during exercise. During phlorizin-induced NGD, increments in both Rdtissueand GF are impaired due to a diminished fuel supply from plasma glucose and a sustained reduction in increments of MCRg.
Differences in Neuronal Firing Rates in Pallidal and Cerebellar Receiving Areas of Thalamus in Patients With Parkinson's Disease, Essential Tremor, and Pain
Authors: Molnar G. F. , Pilliar A. , Lozano A. M. , Dostrovsky J. O.
Published: February 2005

The motor symptoms of Parkinson's disease (PD) are thought to result from increased inhibitory outflow from the basal ganglia to the pallidal receiving areas of thalamus (ventral oral anterior and posterior—Voa,Vop). To test this hypothesis, we examined the firing rates of neurons in pallidal and cerebellar receiving areas of thalamus in five PD patients and compared them to those of neurons in comparable regions of motor thalamus in two other patient groups where hyperactivity of GPi is not believed to occur [essential tremor (ET), pain]. Neuronal recordings were made during microelectrode-guided functional stereotactic neurosurgery. The mean spontaneous firing rate (MSFR) of neurons classified as voluntary neurons and presumed to be in pallidal receiving areas of thalamus in PD patients [7.4 ± 1.0 (SE) Hz] was significantly lower ( P < 0.01) than in the ET (18.1 ± 3.0 Hz) and pain (19.0 ± 1.9Hz) groups. In contrast, the MSFR of neurons classified as kinesthetic and presumed to be primarily in the cerebellar receiving area of thalamus (ventral intermediate—Vim), although some are probably in the deep shell region of the ventrocaudal nucleus (VPLa), was significantly greater in ET patients (25.8 ± 3.5 Hz) than in the PD (14.3 ± 1.6 Hz; P < 0.01) and pain (16.1 ± 1.5 Hz; P < 0.05) groups. Similar findings were obtained when the neurons were grouped according to their estimated locations in Voa/Vop and Vim of motor thalamus. These data provide support for the prediction of the classical pathophysiological model of PD and moreover suggest that pathophysiology in the cerebello-thalamo-cortical pathway may be a possible cause of tremor in ET patients.
Dependency of the Interaural Phase Difference Sensitivities of Inferior Collicular Neurons on a Preceding Tone and Its Implications in Neural Population Coding
Authors: Furukawa Shigeto , Maki Katuhiro , Kashino Makio , Riquimaroux Hiroshi
Published: February 2005

This study examined the sensitivities of the neuronal responses in the inferior colliculus (IC) to the interaural phase difference (IPD) of a preceding tone, and explored its implications in the neural-population representation of the IPD. Single-unit responses were recorded from the IC of anesthetized gerbils. The stimulus was a dichotic tone sequence with a common frequency (typically the unit’s best frequency) and level (10–20 dB relative to the threshold), consisting of a conditioner (200 ms) followed by a probe (50 ms) with a silent gap (5–100 ms) between them. The IPDs of the 2 tones were varied independently. The presence of a conditioner generally suppressed the probe-driven responses; the effect size increased as the conditioner IPD approached the unit’s most responsive IPD. The units’ preferred IPDs were relatively invariant with the conditioner IPD. Two types of models were used to evaluate the effects of a conditioner on the IPD representation at the level of IC neural population. One was a version of the population-vector model. The other was the hemispheric-channel model, which assumed that the stimulus IPD is represented by the activities of 2 broadly tuned hemispheric channels. Both models predicted that, in the presence of a conditioner, the IPD representation would shift in a direction away from the conditioner IPD. This appears to emphasize the difference between the conditioner and the probe IPDs. The results indicate that in the IC, neural processes for IPD adapt to the stimulus history to enhance the representational contrast between successive sounds.
Individual Differences in the Modulation of Fear-Related Brain Activation by Attentional Control
Authors: Mathews Andrew , Yiend Jenny , Lawrence Andrew D.
Published: February 2005

In this article, we consider the extent to which variations in the neural activation associated with fear-related stimuli are obligatory or optional. More specifically, we investigated modulation of activation according to type of encoding operation, and how this relates to individual differences in fearfulness and attentional control. In an fMRI study, fear-related (relative to neutral) pictures preferentially activated many of the regions involved in a hierarchical system responsible for organizing defensive behavior, and differential activation in some of these areas was related to self-reported individual variations in fearfulness. Preferential activation according to type of stimulus persisted to a limited extent even when attention was diverted from its emotional aspects. Importantly, however, encoding tasks involving attention to emotional versus nonemotional attributes of the same pictures revealed a pattern of greater activation during emotional encoding, similar to that differentiating fear-related from neutral stimuli. Again, the degree of modulation varied according to individual differences. We conclude that fear-related pictures can recruit activation in the defensive system even when attention is directed elsewhere, but that the extent of this activation is modulated by attentional control mechanisms. More critically, both differential activation and its modulation by attentional control are related to individual variations in emotional vulnerability, in a manner that conforms to predictions derived from existing theoretical accounts.
Neural Correlates of Detecting Pretense: Automatic Engagement of the Intentional Stance under Covert Conditions
Authors: German Tim P. , Niehaus Jeffrey L. , Roarty Meghan P. , Giesbrecht Barry , Miller Michael B.
Published: February 2005

Typically developing children begin to produce and understand pretend play between 18 and 24 months of age, and early pretense has been argued to be a candidate “core” capacity central to the deployment of representations of other peoples' mental states—“theory of mind.” In a functional magnetic resonance imaging study, 16 healthy adult volunteers were imaged while watching short (5 sec) clips of actors who either performed simple everyday actions or pretended to perform a similar set of actions, under covert conditions (e.g., participants were not directed to attend to actors' mental states). There was increased activity in the medial prefrontal areas (Brodmann's areas [BA] 9/6/32, 9, and 10), inferior frontal gyrus bilaterally (BA 44, 47), temporo-parietal regions (BA 21 and 22), and parahippocampal areas, including the amygdala, when subjects viewed pretend actions as compared with real actions. This result suggests that at least some areas previously implicated in making explicit mental state judgments are also strongly activated in response to actions that call for mental state interpretation (e.g., pretense) even when there is no explicit instruction for “mind reading.” This outcome is discussed in terms of accounts that propose “theory of mind” to be underwritten by automatic specialized mechanisms for the interpretation of the behavior of social agents.
Constant Raindrop Fall Speed Profiles Derived from Doppler Radar Data Analyses for Steady Nonconvective Precipitation
Authors: Nissen Robert , List Roland , Hudak David , McFarquhar Greg M. , Lawson R. Paul , Tung N. P. , Soo S. K. , Kang T. S.
Published: February 2005

For nonconvective, steady light rain with rain rates <5 mm h−1 the mean Doppler velocity of raindrop spectra was found to be constant below the melting band, when the drop-free fall speed was adjusted for pressure. The Doppler radar–weighted raindrop diameters varied from case to case from 1.5 to 2.5 mm while rain rates changed from 1.2 to 2.9 mm h−1. Significant changes of advected velocity moments were observed over periods of 4 min.

These findings were corroborated by three independent systems: a Doppler radar for establishing vertical air speed and mean terminal drop speeds [using extended Velocity Azimuth Display (EVAD) analyses], a Joss–Waldvogel disdrometer at the ground, and a Particle Measuring System (PMS) 2-DP probe flown on an aircraft. These measurements were supported by data from upper-air soundings. The reason why inferred raindrop spectra do not change with height is the negligible interaction rate between raindrops at low rain rates. At low rain rates, numerical box models of drop collisions strongly support this interpretation. It was found that increasing characteristic drop diameters are correlated with increasing rain rates.
Aerosol Characteristics and Radiative Impacts over the Arabian Sea during the Intermonsoon Season: Results from ARMEX Field Campaign
Authors: Moorthy K. Krishna , Babu S. Suresh , Satheesh S. K.
Published: February 2005

During the second phase of the Arabian Sea Monsoon Experiment (ARMEX-II), extensive measurements of spectral aerosol optical depth, mass concentration, and mass size distribution of ambient aerosols as well as mass concentration of aerosol black carbon (BC) were made onboard a research vessel during the intermonsoon period (i.e., when the monsoon winds are in transition from northeasterlies to westerlies/southwesterlies) over the Arabian Sea (AS) adjoining the Indian Peninsula. Simultaneous measurements of spectral aerosol optical depths (AODs) were made at different regions over the adjoining Indian landmass. Mean AODs (at 500-nm wavelength) over the ocean (∼0.44) were comparable to those over the coastal land (∼0.47), but were lower than the values observed over the plateau regions of central Indian Peninsula (∼0.61). The aerosol properties were found to respond distinctly with respect to change in the trajectories, with higher optical depths and flatter AOD spectra associated with trajectories indicating advection from west Asia, and northwest and west-coastal India. On average, BC constituted only ∼2.2% to total aerosol mass compared to the climatological values of ∼6% over the coastal land during the same season.

These data are used to characterize the physical properties of aerosols and to assess the resulting short-wave direct aerosol forcing. The mean values were –27 W m−2 at the surface and −12 W m−2 at the top of the atmosphere (TOA), resulting in a net atmospheric forcing of +15 W m−2. The forcing also depended on the region from where the advection predominates. The surface and atmospheric forcing were in the range −40 to −57 W m−2 and +27 to +39 W m−2, respectively, corresponding to advection from the west Asian and western coastal India where they were as low as −19 and +10 W m−2, respectively, when the advection was mainly from the Bay of Bengal and from central/peninsular India. In all these cases, the net atmospheric forcing (heating) efficiency was lower than the values reported for northern Indian Ocean during northern winter, which is attributed to the reduced BC mass fraction.
Pharmacokinetics and Pharmacodynamics of Multiple Weekly Subcutaneous Efalizumab Doses in Patients With Plaque Psoriasis
Authors: Mortensen Deborah L. , Walicke Patricia A. , Wang Xiaolin , Kwon Paul , Kuebler Peter , Gottlieb Alice B. , Krueger James G. , Leonardi Craig , Miller Bruce , Joshi Amita
Published: February 2005

Efalizumab pharmacokinetics, pharmacodynamics, and efficacy were assessed after subcutaneous administration of 1.0 or 2.0 mg/kg/wk for 12 weeks with 12 weeks of follow‐up in subjects with psoriasis. Steady‐state serum concentrations were achieved by 4 and 8 weeks, respectively. Cmax was 12 and 31 μg/mL, occurring ∼2 days after a SC dose. Serum trough levels were 9 and 24 μg/mL, and CL/Fss was 24 and 16 mL/kg/d. At both doses, CD11a expression on T lymphocytes was maximally down‐modulated to ∼20% of baseline, and CD11a binding sites were >95% saturated. The extent of this PD effect was less for other leukocytes. Leukocyte counts increased by ∼40%, with the majority of this increase related to a significant but reversible increase in the lymphocyte population. Maximal pharmacodynamic effects were sustained at both dose levels through the course of treatment and were commensurate with improvements in psoriasis.
Pharmacokinetics of Alpha‐Lipoic Acid in Subjects With Severe Kidney Damage and End‐Stage Renal Disease
Authors: Teichert Jens , Tuemmers Tina , Achenbach Harald , Preiss Christa , Hermann Robert , Ruus Peter , Preiss Rainer
Published: February 2005

In an open‐label, parallel‐group study involving 16 patients (8 with severely reduced renal function, 8 with end‐stage renal disease needing hemodialysis), the effect of renal function on the pharmacokinetics, metabolism, and safety and of alpha‐lipoic acid (thioctic acid) was evaluated by comparing the pharmacokinetic parameters with those of a reference group of 8 healthy subjects. Alpha‐lipoic acid 600 mg was administered orally once daily for 4 days, and the pharmacokinetic parameters were measured on days 1 and 4. The mean percentage of the administered dose excreted in urine as parent compound was 0.2 and 0.05 in healthy subjects and subjects with severely reduced renal function, respectively. Assuming a bioavailability of 30%, this represents 0.67% and 0.17% of the bioavailable amount of alpha‐lipoic acid, respectively. The percentage of total urinary recovered amounts of alpha‐lipoic acid and 5 of its metabolites was 12.0 on both days. The respective values for patients with severe kidney damage were 5.2% (day 1) and 6.4% (day 4). The total percentage of the administered dose removed by hemodialysis was 4.0 in patients with end‐stage renal disease. Renal clearance of alpha‐lipoic acid and its major metabolites, 6,8‐bismethylthio‐octanoic acid, 4,6‐bismethylthio‐hexanoic acid and 2,4‐bismethylthio‐butanoic acid, were significantly decreased in subjects with kidney damage compared to the reference group. Apparent total clearance of alpha‐lipoic acid was poorly correlated with creatinine clearance. There is strong evidence that alpha‐lipoic acid is mainly excreted by nonrenal mechanism or further degraded to smaller units in the catabolic process. The significantly increased area under the curve values of 4,6‐bismethylthio‐hexanoic acid and half‐lives of 2,4‐bismethylthio‐butanoic acid on both days in patients with severely reduced function and end‐stage renal disease were not considered to be clinically relevant. Although trough levels of both metabolites tend to increase slightly in these subjects, no accumulation effects were detected. We conclude that the pharmacokinetics of alphalipoic acid are not influenced by creatinine clearance and are unaffected in subjects with severely reduced kidney function or end‐stage renal disease. Hemodialysis did not significantly contribute to the clearance of alpha‐lipoic acid. Hence, dose adjustment of alpha‐lipoic acid is not necessary in patients with renal dysfunction.