bluuebunny/crossref_metadata_2025 huggingface dataset:
Cold-cathode Penning discharge-based ionizer for detection of hyperthermal neutral beams
Authors: Abolmasov S. N. , Samukawa S.
Published: July 2007

Plasmas produced in a cold-cathode Penning discharge have been studied for possible use as an active ionizing medium in commercial quadrupole mass/energy analyzers for detection of low-energy neutral beams. Two distinct Penning discharge modes have been examined: (1) high-pressure (HP) mode and (2) high magnetic field (HMF) mode. It is shown that the ionization efficiency in the HP mode is independent of the length of ionization region; however, somewhat high working pressures (p>10−4Torr) and large discharge currents limit the practical use of this mode. This is not the case in the HMF mode, which appears at lower pressures, with an effective ionization region length of the order of electron cyclotron radius. The design and operation of a compact (5×4×4cm3), low-maintenance ionizer based on a Penning cell with permanent magnets is described. The ability to ionize 40eV neutral-argon beams with subsequent detection in a Hiden EQP energy-resolved mass spectrometer is shown. The ionization efficiency of the ionizer was found to be as high as 10−3. Unlike conventional electron impact ionizers, the Penning discharge configuration allows to eliminate the thermal background component in the detected signal. The ionizer has potential application for the detection of hyperthermal neutral beams of various species.
Syntheses and characterization of new polydentate amide ligands with inorganic tin (II) and lead (II) ions
Authors: Singh Bibhesh K. , Mishra Parashuram , Garg Bhagwan S.
Published: July 2007

Complexes of inorganic Sn(II) and Pb(II) with new ligands N0′,N″-bis(3-carboxy-1-oxopropanyl) 2-amino-N-arylbenzamidine (C21H21N3O6) and N′,N″-bis(3-carboxy-1-oxophenelenyl) 2-amino-N-arylbenzamidine (C29H21N3O6) have been synthesized and characterized by elemental analyses, vibrational spectra, electronic spectra, 1H NMR spectra, TOF-mass spectra, thermal studies and X-ray powder diffraction studies. The infrared and 1H NMR spectral data are in agreement with coordination of amide and carboxylate oxygen of the ligands giving a MO4 tetrahedral chromophore. The elemental analyses and mass spectral data are consistent with the formation of ML complexes. Kinetic and thermodynamic parameters were computed from the thermal data using Coats and Redfern method, which confirm first order kinetics. X-ray powder diffraction determines the cell parameters of the complexes. Molecular structures of the complexes have been optimized by MM2 calculations and suggest a tetrahedral geometry around metal (II) ions.
Arsacyclopentadienyl anions: Structure, properties and aromaticity
Authors: Ghiasi Reza
Published: July 2007

The electronic structure and properties of a series of Arsacyclopentadienyl anions have been investigated using hybrid density functional B3LYP theory. Basic measurements of aromatic character are derived from structure, molecular orbital and magnetic properties. Energetic criteria suggest that the As12 and As123 isomers favor conspicuous stabilization in di-arsa and tri-arsa isomers, respectively. By magnetic criteria, these systems are among the most aromatic of the family. Bond order analyses reveal that they derive part of their stability from ionic contributions to the bonding. Overall, magnetic aromaticity decreases with increasing number of As atoms.
Preparation and structural characterisation of the cation-π complexes [{(Me3Si)2NK} · (tBu-C6H5)]2 and [{(Me3Si)2NK} · (Me3-C6H3)]2
Authors: Randazzo John B. , Jacob Morris J. , Henderson Kenneth W.
Published: July 2007

Two new arene solvates [{(Me3Si)2NK} · (tBu-C6H5)]2 (1) and [{(Me3Si)2NK} · (Me3-C6H3)]2 (2) have been synthesised and characterised in the solid state by single-crystal X-ray diffraction analyses. Each complex was prepared through dissolution of potassium hexamethyldisilazide (KHMDS) in either tert-butylbenzene or mesitylene followed by crystallisation. The crystal structures of both 1 and 2 are composed of dimeric K2N2 ring aggregates, where each of the metal centres is solvated by either tert-butylbenzene (1) or mesitylene (2) through η6 – cation-π interactions. In addition, the potassium centres within each dimer have a number of intramolecular agostic K ··· C interactions with the methyl groups of the HMDS anion.
Synthesis and characterisation of 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) and its application of simultaneous second order derivative spectrophotometric method for determination of cobalt(II), nickel(II) and vanadium(V)
Authors: Praveen Kumar A. , Mohan Reddy K.P.P.R. , Veera Reddy T. , Raveendra Reddy P. , Krishna Reddy V.
Published: July 2007

2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) has been synthesized, characterized and employed as a simple simultaneous second order derivative spectrophotometric method for the analysis of a three-component system containing cobalt(II) nickel(II) and vanadium(V) without separation. The reagent (HMBATSC) reacts with cobalt(II), nickel(II) and vanadium(V) at pH 6.0, forming soluble brown, yellow and green coloured species, respectively. Cobalt, nickel and vanadium present in the mixture are simultaneously determined without solving the simultaneous equations by measuring the second derivative amplitudes at 460 nm, 450 nm and 430 nm, respectively. Further, the derivative amplitudes obey Beer’s law at 460 nm, 450 nm and 430 nm for Co(II), Ni(II) and V(V) in the range 0.059 – 3.535 μg ml−1, 0.058 – 3.425 μg ml−1 and 0.051 – 4.074 μg ml−1, respectively. A large number of additional ions did not interfere with the method. The simultaneous method can be applied for the determination of cobalt(II) in pharmaceutical samples, nickel(II) in water and plant samples and vanadium(V) in biological samples.
Changes of Oral Trigeminal Sensitivity in Patients After Middle Ear Surgery
Authors: Just Tino , Steiner Susanne , Strenger Tobias , Pau Hans W.
Published: July 2007

Objectives: The specific aim of this study was to re‐investigate the effect of chorda tympani damage on both trigeminal sensitivity and taste ability.

Study Design: Prospective study.

Methods: Capsaicin‐impregnated filter paper strips (5 concentrations, 0.0001–1%) were used to measure trigeminal thresholds. The strips were placed on the anterior tongue for 10 seconds. Thresholds were estimated in two ways: 1) thresholds related to sensory perception and 2) intensity‐related thresholds. The test was applied to 29 patients who underwent middle ear surgery (mean age, 49 yr; 16 females, 13 males). Results were compared with those of 63 healthy subjects (mean age, 40 yr; 36 females, 29 males). In addition to trigeminal thresholds, measures of gustatory function were also obtained using both the validated “taste strips” test kit and electrogustometry.

Results: For lateralized testing with capsaicin, significant differences were found between preoperative and postoperative thresholds and between the operated and nonoperated side, with thresholds being higher postoperatively on the operated side. The sensation‐related thresholds from the operated tongue side exhibited a correlation with the corresponding postoperative electrogustometric thresholds. A higher degree of chorda manipulation was associated with higher postoperative capsaicin thresholds at the operated tongue side.

Conclusion: Pain‐related sensitivity of the tongue decreases after middle ear surgery, indicating that chorda tympani function also influences intraoral trigeminal sensitivity.
Narrow Band Imaging for Detecting Superficial Oral Squamous Cell Carcinoma: A Report of Two Cases
Authors: Katada Chikatoshi , Nakayama Meijin , Tanabe Satoshi , Naruke Akira , Koizumi Wasaburo , Masaki Takashi , Okamoto Makito , Saigenji Katsunori
Published: July 2007

We present two cases of superficial squamous cell carcinoma of the floor of the mouth, which were coincidentally detected by narrow band imaging (NBI) combined with magnifying gastrointestinal endoscopy (GIE) during gastrointestinal evaluation. We successfully removed the lesions using laser assisted with NBI combined with magnifying GIE. Because NBI combined with magnifying GIE shows a well‐demarcated brownish area and scattered foci of microvascular proliferation, it may play an important role in the management of superficial squamous cell carcinoma in the oral cavity.
Spontaneous emergence of modularity in cellular networks
Authors: Solé Ricard V , Valverde Sergi
Published: July 2007

Modularity is known to be one of the most relevant characteristics of biological systems and appears to be present at multiple scales. Given its adaptive potential, it is often assumed to be the target of selective pressures. Under such interpretation, selection would be actively favouring the formation of modular structures, which would specialize in different functions. Here we show that, within the context of cellular networks, no such selection pressure is needed to obtain modularity. Instead, the intrinsic dynamics of network growth by duplication and diversification is able to generate it for free and explain the statistical features exhibited by small subgraphs. The implications for the evolution and evolvability of both biological and technological systems are discussed.
Antoine-François Payen, the 1666Selenelion, and a rediscovered letter to Robert Hooke
Authors: Poole William
Published: July 2007

This note concerns the horizontal eclipse of 16 June 1666, and the Avignon jurisconsult and astronomer Antoine-François Payen's reflections upon it, hisSelenelion ou Apparition Luni-Solaire(Paris, 1666). Payen argued that observation of a horizontal eclipse had to take into account the effects of both atmospheric refraction and diurnal parallax. Payen sent a copy of his work via the Royal Society's Secretary, Henry Oldenburg, to the Curator of Experiments, Robert Hooke. This hitherto lost gift can be identified as Bodleian Library 4° W 27 (14) Jur, and it still bears Payen's autograph letter of presentation. It reached the Bodleian through Sir Hans Sloane, who acquired some of Hooke's books after the latter's death and who subsequently donated well over 1000 of his duplicates to the Bodleian in the early eighteenth century. Payen'sSelenelionwas included in Sloane's shipments by oversight, as it seems to have been Sloane's only copy. A text and translation of Payen's recovered letter to Hooke are provided, as well as a list of further Sloanian books in the Bodleian formerly owned by Hooke.
The use of propofol and remifentanil for the anaesthetic management of a super‐obese patient
Authors: La Colla L. , La Colla G. , Albertin A. , Poli D. , Baruffaldi Preis F. W. , Mangano A.
Published: July 2007

Morbid obesity is defined as body mass index (BMI) > 35 kg.m−2, and super‐obesity as BMI > 55 kg.m−2. We report the case of a 290‐kg super‐obese patient scheduled for open bariatric surgery. A propofol‐remifentanil TCI (target controlled infusion) was chosen as the anaesthetic technique both for sedation during awake fibreoptic nasotracheal intubation and for maintenance of anaesthesia during surgery. Servin's weight correction formula was used for propofol. Arterial blood samples were taken at fixed time points to assess the predictive performance of the TCI system. A significant difference between measured and predicted plasma propofol concentrations was found. After performing a computer simulation, we found that predictive performance would have improved significantly if we had used an unadjusted pharmacokinetic set. However, in conclusion (despite the differences between measured and predicted plasma propofol concentrations), the use of a propofol‐remifentanil TCI technique both for sedation during awake fibreoptic intubation and for Bispectral Index‐guided propofol‐remifentanil anaesthesia resulted in a rapid and effective induction, and operative stability and a rapid emergence, allowing rapid extubation in the operating room and an uneventful recovery.
Supplementation of pre‐oxygenation in morbidly obese patients using nasopharyngeal oxygen insufflation
Authors: Baraka A. S. , Taha S. K. , Siddik‐Sayyid S. M. , Kanazi G. E. , El‐Khatib M. F. , Dagher C. M. , Chehade J.‐M. A. , Abdallah F. W. , Hajj R. E.
Published: July 2007

During apnoea following induction of anaesthesia, morbidly obese patients may suffer a rapid decrease in oxygen saturation. This study compares pre‐oxygenation alone with pre‐oxygenation followed by nasopharyngeal oxygen insufflation on the onset of desaturation occurring during the subsequent apnoea. A randomised controlled trial was performed in 34 morbidly obese patients undergoing gastric bypass or gastric band surgery. Seventeen patients received nasopharyngeal oxygen supplementation following pre‐oxygenation (Study group, body mass index = 41.8 (6.9) kg.m−2), and the other 17 patients received pre‐oxygenation alone (Control group, body mass index = 42.7 (5.4) kg.m−2). Time from the onset of apnoea until Spo2 fell to 95% was compared between the two groups with a cut‐off of 4 min. In the control group, the Spo2 fell from 100% to 95% during the subsequent apnoea in 145 (27) s, with a significantly negative correlation (r2 = 0.66, p < 0.05) between the time to desaturation to 95% and the body mass index. In the study group, the Spo2 was maintained in 16 of 17 patients at 100% for 4 min when apnoea was terminated. In conclusion, nasopharyngeal oxygen insufflation following pre‐oxygenation in morbidly obese patients delays the onset of oxyhaemoglobin desaturation during the subsequent apnoea.
Plant colonization: are wind dispersed seeds really dispersed by birds at larger spatial and temporal scales?
Authors: Wilkinson David M.
Published: July 2007

ABSTRACT. It is suggested that many plant species often thought of as wind dispersed may in fact be largely dispersed by animals, mostly birds, at larger spatial and temporal scales. This possibility is illustrated by using data on Holocene tree migrations in Europe. It is suggested that exploratory movements, often by young birds, may play an important role in such dispersal rather than the classic return migrations of birds. In the case of European trees there could have been active selection for rapid migrations occurring even in the glacial refugia sites in the mountains of southern Europe. Plant migration rates, and hence the ability to deal with climatic change, may have been lower before the evolution of a diverse avifanua. It is suggested that for many ‘wind dispersed’ seeds the wind dispersal mechanism is adapted to local dispersal (over distances of a few canopy diameters) and larger scale dispersion is due to birds.
Internode length in Pisum. Further studies on the ‘micro’ gene, lm
Authors: Reid James B. , Ross John J.
Published: July 2007

Reid, J. B. and Ross, J. J. 1988. Internode length in Pisum. Further studies on the ‘micro’ gene, lm. ‐ Physiol. Plant. 72: 547–554.

In the garden pea, Pisum sativum L., gene lm confers the micro phenotype. The shoots of lm plants may be described as scaled‐down versions of comparable Lm plants, with reduced internode length, leaflet size and rate of leaf expansion. However, the first phenotypic effect of gene lm is on root morphology. The gene results in curling and reduced elongation of the roots and, eventually, degeneration of the root cortex. These changes commence prior to any major visible effects in the shoot. The primary action of the lm gene does not appear to be confined to the root system, however, since epicotyl grafts between Lm and lm plants showed no graft‐transmissible effects. The effects of gene lm are also apparent in dark‐grown plants. Microdwarf plants (lm le) respond well to gibberellin A1 (GA1), but do not elongate to the same extent as dwarf (Lm le) plants. The two genotypes contain the same complement of GA‐like substances. It is argued that gene lm is unlikely to be directly involved with GA‐metabolism or the reception of the GA signal, but rather reduces the GA response by influencing some aspect of normal cell development, which results in the wide range of pleiotropic effects observed. Consequently, it may be misleading to continue to classify this gene simply as an internode length mutant.
Role of abscisic acid in a Ca2+ second messenger system
Authors: Owen John H.
Published: July 2007

Owen, J. H. 1988. Role of abscisic acid in a Ca2+ second messenger system. ‐ Physiol. Plant. 72:637–641.

Recent investigations have shown that Ca2+ acts as a second messenger in plant cell coupling of response to stimulus. Data now suggests that abscisic acid (ABA) plays a role as Ca2+‘agonist’ in this Ca2+ messenger system, although the molecular basis of such an interaction has not yet been fully investigated. ABA appears to possess a universal Ca2+‘agonist’ role because it elicits responses in systems as diverse as mammalian contractile tissue and cyanobacteria. ABA may therefore be of a wider biological significance than previously recognised.
Toxic oxygen species and protective systems of the chloroplast
Authors: Salin Marvin L.
Published: July 2007

Salin, M. L. 1988. Toxic oxygen species and protective systems of the chloroplast. ‐Physiol. Plant. 72: 681–689.

As a consequence of living in an environment enriched in oxygen, which they themselves at least partially generate, photosynthetic organisms are exposed to large fluxes of oxyradicals and reactive oxygen species. Among these are superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen. These highly reactive intermediates pose the threat of toxicity unless neutralized by scavenger substrates or enzymes. The production of oxyradicals and intermediates by chloroplasts as well as the means of protection are discussed in this review.
Cell‐wall lysing enzymes and products of cell‐wall digestion elicit ethylene in citrus
Authors: Baldwin Elizabeth A. , Biggs R. Hilton
Published: July 2007

Ethylene production was induced in Valencia oranges [Citrus sinensis(L.) Osbcck] by injection of the fungal enzyme mixture Pectolyase (Aspergillus japonicus) which contains pectolytic enzymes into the peel. The mixture also stimulated production of 1‐aminocyclopropane‐1‐carboxylic acid (ACC). Cycloheximide partially inhibited the Pectolyase‐induced ethylene response. Pectin fragments, resulting from partial acid hydrolysis or Pectolyase digestion, caused an increase in ethylene production when injected into the peel of intact orange fruits. Pectic fragments produced by fungal enzymes are known to be elicitors of phytoalexins and in this study are shown to elicit ethylene in citurs.
Electrophysiological evidence for the herbicidal mode of action of phosphonic acid esters
Authors: Linsel Gunter , Dahse Ingo , Müller Eberhard
Published: July 2007

The electrical membrane potential of leaf cells of the higher aquatic plant Egeria densa Planchon, measured with microelectrodes, was immediately depolarized after treatment with 0.29 mM of the dialkyl phosphonic ester, O, O‐di‐n‐butyl‐(1‐n‐butylamino‐cyclohexyl)‐phosphonate (PABT). This depolarization was followed by a strong electrolyte efflux after ca 90 min. Active photosynthesis or respiration as well as an intact plasma membrane was essential for this effect. An increased concentration of thiobarbituric acid (TBA)‐reactive agents observed within this period suggests that membrane destruction by lipid peroxidation was responsible for the electrolyte efflux. Antioxidants such as α‐tocopherol (0.25 mM) and ascorbic acid (1 mM) stopped electrolyte efflux, but did not affect the depolarization.

Fusicoccin (1 μM) prevented PABT‐induced membrane depolarization and the subsequent electrolyte efflux. Also, the ATPase inhibitor, DES (50 üM), as well as substances which stimulate the proton pump such as sucrose (30 mM), AIB (10 μM), and acetate (1 mM), prevented PABT‐mediated electrolyte efflux. The depolarizing effect of PABT was also obviated above pH 7.5. Thus, if the PABT‐induced depolarization was inhibited no membrane destruction occurred whereas depolarization alone was not a sufficient condition for the development of the PABT action. The initial depolarizing effect of PABT cannot be explained by a physical interaction with the lipid part of the plasma membrane. Thus, a metabolism‐driven mode of action connected to plasma membrane energization has to be assumed.
Compositional changes associated with plasma membrane thickening during floral induction of spinach
Authors: Penel Claude , Auderset Guy , Bernardini Nicola , Castillo Federico J. , Greppin Hubert , Morré D. James
Published: July 2007

Floral induction in the long‐day plant spinach (Spinacia oleracea L. cv. Nobel) was accompanied by a thickening of the plasma membrane. Densitometry analyses showed that the light space of the dark‐light‐dark pattern of the membrane was not changed upon photoinduction. Rather, the increase was due to an enhancement of the dark layer adjacent to the cell wall. Parallel analyses of protein and phospholipid composition revealed no marked changes in protein composition or biosynthetic rate, protein phosphorylation, glycolipids and/or phospholipids as a result of the 24 h of continuous light sufficient to induce flowering. Photoinduction, however, was accompanied by an increase in the relative amount of plasma membrane sterols which may be related to the membrane thickening.
The “Commons” Versus the “Commodity”: Alter‐globalization, Anti‐privatization and the Human Right to Water in the Global South
Authors: Bakker Karen
Published: July 2007

Abstract: In response to the growth of private sector involvement in water supply management globally, anti‐privatization campaigns for a human right to water have emerged in recent years. Simultaneously, alter‐globalization activists have promoted alternative water governance models through North‐South red‐green alliances between organized labour, environmental groups, women's groups, and indigenous groups. In this paper, I explore these distinct (albeit overlapping) responses to water privatization. I first present a generic conceptual model of market environmentalist reforms, and explore the contribution of this framework to debates over ‘neoliberalizing nature’. This conceptual framework is applied to the case of anti‐privatization activism to elucidate the limitations of the human right to water as a conceptual counterpoint to privatization, and as an activist strategy. In contrast, I argue that alter‐globalization strategies—centred on concepts of the commons—are more conceptually coherent, and also more successful as activist strategies. The paper concludes with a reiteration of the need for greater conceptual precision in our analyses of neoliberalization, for both academics and activists.
The Polanyian Way? Voluntary Food Labels as Neoliberal Governance
Authors: Guthman Julie
Published: July 2007

Abstract:  Voluntary food labels that express ecological, social, and/or place‐based values have been posed as an important form of resistance to neoliberalization in the Polanyian sense of protecting land, other natural resources, and labor from the ravages of the market. At the same time, these labels are in some respects analogs to the very things they are purported to resist, namely property rights that allow these ascribed commodities to be traded in a global market. After reviewing the Polanyian claims about these labels, the paper examines how these labels are operationalized and notes important differences in the sort of barriers to entry they erect, which in turn have quite different distributional consequences. It then goes on to discuss how these labels look to be an expression of roll‐out neoliberalization. Following Heynen and Robbins who note four dominant aspects of neoliberalization of environmental governance (governance, privatization, enclosure, and valuation), to which a fifth (devolution) is added, the paper shows how these labels not only concede the market as the locus of regulation, but in keeping with neoliberalism's fetish of market mechanisms, they employ tools designed to create markets where none previously existed. In recognition that neoliberal political economies and subjectivities have delimited the possible, the paper also grapples with how these labels may produce political openings outside of their most proximate effects.
No Association of the ACTN3 Gene R577X Polymorphism with Endurance Performance in Ironman Triathlons
Authors: Saunders C. J. , September A. V. , Xenophontos S. L. , Cariolou M. A. , Anastassiades L. C. , Noakes T. D. , Collins M.
Published: July 2007

Alpha‐actinins are major structural components of the Z‐discs in skeletal muscle. Alpha‐actinin 3 is encoded by the ACTN3 gene and is expressed only in type II muscle fibres. Homozygosity for the nonsense mutation, 577X, within ACTN3 results in deficiency of α‐actinin‐3 but does not result in an abnormal muscular phenotype. Previous research has found an association of the 577R allele with sprinting and/or power performance. It has also been suggested that the 577X allele may confer an advantage during endurance events. Four hundred and fifty seven Caucasian male triathletes who completed either the 2000 and/or 2001 226 km South African Ironman Triathlons, and 143 Caucasian controls, were genotyped for the R577X mutation within the ACTN3 gene. There were no significant differences in either the genotype (P = 0.486) or allele (P = 0.375) frequencies within the fastest, middle of the field or slowest Caucasian male finishers and the control population. In conclusion, the R577X polymorphism within the ACTN3 gene was not associated with ultra‐endurance performance in the 2000 and 2001 South African Ironman Triathlons.
Design and Analysis of Genetic Association Studies to Finely Map a Locus Identified by Linkage Analysis: Assessment of the Extent to Which an Association Can Account for the Linkage
Authors: Hanson R. L. , Knowler W. C.
Published: July 2007

Association studies are often used to finely map quantitative trait loci identified by linkage analysis. Once a polymorphism associated with the trait has been identified, it may be useful to conduct linkage analyses which adjust for this polymorphism to determine the extent to which the association accounts for the linkage signal. However, methods for conducting statistical significance tests for an observed reduction in the linkage signal are not well developed. In the present study we develop methods for assessment of the statistical significance of an observed reduction in the variance due to the linked locus, with variance components or with Haseman‐Elston linkage methods. Simulations indicate that these methods have appropriate levels of type I error and that, like other association statistics, their power depends on the magnitude of linkage disequilibrium between functional and marker alleles and on the extent of similarity between the frequency of the functional allele and the frequency of the associated marker allele. These methods can help determine which association results are likely due to strong linkage disequilibrium with functional alleles and, thus, can facilitate the selection of small chromosomal regions for more extensive study.
Comparing Offers and Take‐ups of Employee Health Insurance across Race, Gender, and Decade*
Authors: Keene Jennifer Reid , Prokos Anastasia H.
Published: July 2007

How often do U.S. employees receive health insurance offers from employers? When offered, how often do they take up their employer‐based health insurance? This article uses the 1992 and 2002 waves of the National Study of the Changing Workforce (NSCW) to investigate changes in access to (offers) and employees electing to accept, take, or purchase their employers’ health insurance plans (take‐ups) among wage and salaried workers. Although much research has studied employee health benefits, little has examined the intersection of gender and race regarding both offers and take‐ups of such benefits. Logistic regression results indicate that offers and take‐ups of personal health benefits declined from 1992 to 2002, net of salient controls. Further analyses demonstrate that these declines did not affect all workers identically. Offers declined somewhat for both women and men among whites and African Americans, but declined more among Hispanic women and men. Among other ethnoracial groups, offers declined the most among men, but increased among comparable women. Take‐ups declined among white men and Hispanic workers. However, white and African American women's take‐ups did not change and among African American men take‐ups increased. We discuss the need to examine gender and race simultaneously and urge researchers to more closely examine changes in health benefit offers and take‐ups.
The Influence of University R & D Expenditures on New Business Formations and Employment Growth
Authors: Kirchhoff Bruce A. , Newbert Scott L. , Hasan Iftekhar , Armington Catherine
Published: July 2007

Since new firms generally lack the resources necessary to compete with their larger, older counterparts in the knowledge development process, we argue that they often rely on spillovers to fuel their own innovative efforts. Thus, we hypothesize that new firms will tend to form in areas characterized by high levels of university research and development (R & D) expenditures and that these births will in turn stimulate the local economy by generating increases in employment level and growth. We test our hypotheses at the U.S. labor market area level using secondary data from various government sources for the years 1990 through 1999. Our results demonstrate that university R & D expenditures are positively related to new firm formations, and that these new firm formations are positively related to employment level and change. These findings suggest that university R & D expenditures are an important indirect contributor to overall economic growth by encouraging primary and secondary firm births.
Effect of the Atrioventricular Relationship on Atrial Refractoriness in Humans
Authors: CALKINS HUGH , EL‐ATASSI RAFEL , LEON ANGEL , KALBFLEISCH STEVEN , BORGANELLI MARK , LANGBERG JONATHAN , MORADY FRED
Published: July 2007

CALKINS, H. et al.: Effect of the Atrioventricular Relationship on Atrial Refractoriness in Humans. Atrial arrhythmias occur frequently in the setting of increased atrial size and pressure. This may result from contraction‐excitation feedback. The objective of this study was to investigate the effect of alterations in atrial pressure, induced by varying the atrioventricular (AV) interval, on atrial refractoriness, and on the frequency of induction of atrial fibrillation. Twenty‐seven patients without structural heart disease participated in the study. In each patient the atrial effective (ERP) and absolute refractory period (ARP) were measured during AV pacing at a cycle length of 400 msec and AV intervals of 0, 120, and 160 msec. The ERP was defined as the longest extrastimulus coupling interval that failed to capture with an extrastimulus current strength of twice the stimulation threshold. The ARP was defined in a similar manner with an extrastimulus current strength of 10 mA. The ERP and ARP were determined during continuous pacing using the incremental extrastimulus technique. A subset of patients had the pacing protocol performed during autonomic blockade. As the AV interval was increased from 0 to 160 msec, the peak right atrial pressure decreased from 16 ± 4 mmHg to 7 ± 3 mmHg and the mean right atrial pressure decreased from 7 ± 3 mmHg to 3 ± 22 mmHg (P < 0.001). The atrial ERP and ARP did not change with alterations in the AV interval. There was no difference in the frequency of induction of atrial fibrillation. Similar results were obtained during autonomic blockade. These findings suggests that the phenomenon of contraction‐excitation feedback may not be of importance in the development of atrial arrhythmias in patients without structural heart disease.
Stimulation Hierarchy: Optimal Sequence for Double and Triple Extrastimuli During Electrophysiological Studies
Authors: ARTOUL SAMIR G. , FISHER JOHN D. , KIM SOO G. , FERRICK KEVIN J. , ROTH JAMES A.
Published: July 2007

ARTOUL, S.G., et al.: Stimulation Hierarchy: Optimal Sequence for Double and Triple Extrastimuli During Electrophysiological Studies. To determine the optimal ventricular stimulation sequence, an 11‐step programmed electrical stimulation (PES) protocol was completed, even if a ventricular arrhythmia (VA) was induced with earlier steps. The protocol consisted of one, two, and three extrastimuli during sinus rhythm (SR), and at two drive pacing rates (VP1 and VP2) plus rapid burst and ramp pacing. By analyzing the 79 completed protocols that induced the clinical arrhythmia, the following were deter‐mined: (1) the frequency of induced clinical and nonclinical VA with each stimulation step; (2) the yield ratio (YR) of each step, defined as the probability of inducing clinical versus nonclinical arrhythmia; (3) the cumulative yield of induced clinical and nonclinical arrhythmia with two widely used stimulation sequences, i.e., triple extrastimuli delivered early in the stimulation protocol (MMC sequence) and triple extrastimuli delayed until after double extrastimuli failed to induce the clinical arrhythmia (B sequence); (4) the relative efficiency of these sequences were determined. The percentage of induced clinical and nonclinical arrhythmia with SR + 3 extrastimuli, VP1 + 2 extrastimuli, and VP2 + 2 extrastimuli were (53%, 5%), (36%, 5%), and (41%, 9%), respectively. The cumulative yield of induced clinical VA with the MMC‐type sequence reached 55% by the third step of the protocol, whereas 50% was attained only at the eighth step of the B‐type sequence. The cumulative percentage of induced nonclinical VA with either sequence was similar during the early steps of the protocol. The MMC sequence was more efficient, requiring overall 36% of potential steps for clinical arrhythmia induction, compared with 48% for the B sequence (P < 0.001). For questionable arrhythmia states, e.g., syncope of unknown origin and nonsustained VT, a modified sequence is proposed that may further reduce the induction of uninterpretable arrhythmias.
Bidirectional Tachycardia Induced by Herbal Aconite Poisoning
Authors: TAI YAU‐TING , LAU CHU‐PAK , BUT PAUL PUI‐HAY , FONG PING‐CHING , LI JOHN PO‐SHAN
Published: July 2007

TAI, Y.‐T., et al.: Bidirectional Tachycardia Induced by Herbal Aconite Poisoning. This report details the clinical, electrocardiographic, and electropharmacological characteristics of an unusual case of bidirectional tachycardia induced by aconites present in a Chinese herbal decoction consumed by a previously healthy subject. The tachycardia showed marked susceptibility to vagotonic maneuvers, cholinesterase inhibition, and adenosine triphosphate. The incessant nature of the tachycardia, rapid recurrence after transient suppression, and failure to respond to direct current cardioversion suggested an automatic tachycardia mechanism consistent with known data on the cellular electrophysiological mechanism of aconitine‐mediated arrhythmogenesis. A fascicular or ventricular myocardial origin of the tachycardia with alternating activation patterns, or dual foci with alternate discharge, appeared most plausible. The rootstocks of aconitum plants have been commonly employed in traditional Chinese herbal recipes for “cardiotonic” actions and for relieving “rheumatism.” Multiple pitfalls could occur during the processing of these herbs that might have predisposed to aconite poisoning. The need for strict control and surveillance of herbal substances with low margins of safety is highlighted.
Transesophageal Echocardiographic Diagnosis of a Dehisced Carpentier Mitral Ring
Authors: Masiello Paolo , Itri Francesco , Mastrogiovanni Generoso , Benedetto Giuseppe Di
Published: July 2007

We describe an unusual case of gross dehiscence of a Carpentier mitral ring, not due to bacterial endocarditis, causing severe mitral valve insufficiency and cardiac failure. Diagnosis was made by transesophageal echocardiography (TEE). Mitral valve replacement was then performed.
Real‐Time Three‐Dimensional Stress Echocardiography
Authors: Takuma Shin , Cardinale Carol , Homma Shunichi
Published: July 2007

Cardiovascular stress testing plays a crucial role in the initial detection of coronary artery disease. In exercise stress echocardiography, the rapid acquisition of echocardiography images is critical for accuracy. Real‐time three‐dimensional echocardiography permits the rapid acquisition of a volumetric data set that includes the entire left ventricle and allows the review of multiple, standard two‐dimensional images from a single volumetric data set. Volumetric data can be obtained using both apical and parasternal windows. Often, satisfactory images are obtained in the majority of both prestress and poststress imaging using only an apical volume set. The following is a review of the current applications of real‐time three‐dimensional echocardiography in stress testing.
Centre‐forward
Authors: Miliband Ed
Published: July 2007

Tony Blair recently announced his decision to resign as leader of the decade‐old Labour government. In this essay, Ed Miliband, widely regarded as one of the vanguard of the next generation of Labour politicians, sets out his vision for the future of the progressive left.
Silent Decisions: Limits of Consent and the Terminally Ill Patient
Authors: Brennan Troyen A.
Published: July 2007

Over the past decade we have witnessed a remarkable change in the courts, and presumably in societys, attitude toward the care of the terminally ill patient. In a series of court decisions, judges have consistently ruled that the terminally ill patient's autonomy must be respected, even if that means limiting the patient's care when that is the patient's wish. Moreover, courts have allowed the incompetent patient's family and doctors, when they agree, to make substituted decisions to limit care, that is, decisions which attempt to replicate the choices that the patient would have made about his own treatment were he able to do so. Courts have not, however, offered guidance on those situations in which the incompetent patient's family and physicians disagree with respect to their recommendations concerning the course of therapy the patient would choose. Most importantly, courts have failed to establish clear limits on professional authority in situations where disagreements occur.
Meeting Needs and Rationing Care
Authors: Callahan Daniel
Published: July 2007

I think it is fair to say that there have been two overriding needs of the health care system in the United States for the past couple of decades. One of them is to provide an adequate minimal level of care for all, especially for the underinsured and for those who could be faced by catastrophic health care costs. That need points to an expansion of health care expenditures and to the creation of new programs and strategies. The second need is that of finding a permanent and effective way of controlling the constant escalation of health care costs, and of the proportion of health care costs in our overall economy. That need points to restraint and limitations, not constant expansion.

We are left, then, with two apparently contradiaory needs, each pointing to a major problem, but each standing, it would seem, directly in the path of the other.
Regulating Research and Experimentation: A View from the UK
Authors: McLean Sheila A.M.
Published: July 2007

A medical profession which did not seek improved means to conquer disease would be condemned for dereliction of its duty, Members of the public will not accept the current state of the medical arts as finite but feel justified in expecting the development of more effective therapies for illness, and the promotion of improved means of preventive care.

With this assertion, the distinguished academic, Bernard Dickens, places research firmly in the domain of the public interest. Foster agrees, saying that, “[t]o improve medical care as much as we can, if not to perfect it, means that we have to accept the need for research.” Giesen adds a further emphasis to the search for medical advancements, saying that “freedom of research and scientific inquiry is, in itself, an important aspect of open societies.“
Storing Newborn Blood Spots: Modern Controversies
Authors: Kharaboyan Linda , Avard Denise , Knoppers Bartha Maria
Published: July 2007

Though in existence for over thirty-five years, due to the increasing panoply of possible tests. Newborn screening programs are drawing public attention. Many jurisdictions have mandatory newborn screening programs for treatable disorders. Disorders are detected through tests on blood spots drawn from a newborn’s heel soon after birth and verified through a diagnostic test with follow-up. Unbeknownst to most parents, these blood spot cards are also stored thereafter. Indeed, while dried blood spots (DBSs) are primarily used for screening for health problems, experience demonstrates that they can be made useful in various contexts unrelated to screening.

Newborn dried blood spots have taken on a new life as a result of developments in genetics and the increasing ability of bioinformatics to link DNA information with clinical data. Additionally, storage and secondary uses have been documented to occur without parental consent.
Bioluminescent imaging of Ca2+ activity reveals spatiotemporal dynamics in glial networks of dark‐adapted mouse retina
Authors: Agulhon Cendra , Platel Jean‐Claude , Kolomiets Bogdan , Forster Valérie , Picaud Serge , Brocard Jacques , Faure Philippe , Brulet Philippe
Published: July 2007

Glial Ca2+ excitability plays a key role in reciprocal neuron–glia communication. In the retina, neuron–glia signalling is expected to be maximal in the dark, but the glial Ca2+ signal characteristics under such conditions have not been evaluated. To address this question, we used bioluminescence imaging to monitor spontaneous Ca2+ changes under dark conditions selectively in Müller cells, the principal retinal glial cells. By combining this imaging approach with network analysis, we demonstrate that activity in Müller cells is organized in networks of coactive cells, involving 2–16 cells located distantly and/or in clusters. We also report that spontaneous activity of small networks (2–6 Müller cells) repeat over time, sometimes in the same sequential order, revealing specific temporal dynamics. In addition, we show that networks of coactive glial cells are inhibited by TTX, indicating that ganglion and/or amacrine neuronal cells probably regulate Müller cell network properties. These results represent the first demonstration that spontaneous activity in adult Müller cells is patterned into correlated networks that display repeated sequences of coactivations over time. Furthermore, our bioluminescence technique provides a novel tool to study the dynamic characteristics of glial Ca2+ events in the retina under dark conditions, which should greatly facilitate future investigations of retinal dark‐adaptive processes.
Nitric oxide mediates the vagal protective effect on ventricular fibrillation via effects on action potential duration restitution in the rabbit heart
Authors: Brack Kieran E. , Patel Vanlata H. , Coote John H. , Ng G. André
Published: July 2007

We have previously shown that direct vagus nerve stimulation (VNS) reduces the slope of action potential duration (APD) restitution while simultaneously protecting the heart against induction of ventricular fibrillation (VF) in the absence of any sympathetic activity or tone. In the current study we have examined the role of nitric oxide (NO) in the effect of VNS. Monophasic action potentials were recorded from a left ventricular epicardial site on innervated, isolated rabbit hearts (n= 7). Standard restitution, effective refractory period (ERP) and VF threshold (VFT) were measured at baseline and during VNS in the presence of the NO synthase inhibitor NG‐nitro‐l‐arginine (l‐NA, 200 μm) and during reversing NO blockade with l‐arginine (l‐Arg, 1 mm). Data represent the mean ±s.e.m. The restitution curve was shifted upwards and became less steep with VNS when compared to baseline. l‐NA blocked the effect of VNS whereas l‐Arg restored the effect of VNS. The maximum slope of restitution was reduced from 1.17 ± 0.14 to 0.60 ± 0.09 (50 ± 5%, P < 0.0001) during control, from 0.98 ± 0.14 to 0.93 ± 0.12 (2 ± 10%, P= NS) in the presence of l‐NA and from 1.16 ± 0.17 to 0.50 ± 0.10 (41 ± 9%, P= 0.003) with l‐Arg plus l‐NA. ERP was increased by VNS in control from 119 ± 6 ms to 130 ± 6 ms (10 ± 5%, P= 0.045) and this increase was not affected by l‐NA (120 ± 4 to 133 ± 4 ms, 11 ± 3%, P= 0.0019) or l‐Arg with l‐NA (114 ± 4 to 123 ± 4 ms, 8 ± 2%, P= 0.006). VFT was increased from 3.0 ± 0.3 to 5.8 ± 0.5 mA (98 ± 12%, P= 0.0017) in control, 3.4 ± 0.4 to 3.8 ± 0.5 mA (13 ± 12%, P= 0.6) during perfusion with l‐NA and 2.5 ± 0.4 to 6.0 ± 0.7 mA (175 ± 50%, P= 0.0017) during perfusion with l‐Arg plus l‐NA. Direct VNS increased VFT and flattened the slope of APD restitution curve in this isolated rabbit heart preparation with intact autonomic nerves. These effects were blocked using l‐NA and reversed by replenishing the substrate for NO production with l‐Arg. This is the first study to demonstrate that NO plays an important role in the anti‐fibrillatory effect of VNS on the rabbit ventricle, possibly via effects on APD restitution.
First-Order Numerical Analysis of Linear Thin Layers
Authors: Lebon F. , Ronel S.
Published: July 2007

This paper deals with the first-order numerical analysis of thin layers. Theoretical results are recalled and compared with numerical data obtained on two classical examples. The effects of concentrated forces are discussed.
Early Stall Warning Technique for Axial-Flow Compressors
Authors: Tahara Nobuyuki , Kurosaki Masahiro , Ohta Yutaka , Outa Eisuke , Nakajima Takurou , Nakakita Tomofumi
Published: July 2007

This paper proposes a unique stall risk index based on pressure signals by high-response transducers on the casing wall at the rotor leading-edge location. The aim of the research is to explore the possibility of reducing current excessive stall margin requirement for compressor design based on the worst-case scenario. The index is generated by computing correlation degradation of pressure time histories of current and one revolution before over each blade pitch. Tests conducted on a single-stage low-speed compressor exhibits that the correlation diminishes significantly with proximity to stall, and the proposed technique might have the capability of generating a stall warning signal sufficiently in advance of spike inception. Extensive experiments on a research compressor show that the degree of the index degradation depends on various factors, such as flow coefficient, tip clearance, and rotor blade incidence. In order to obtain a reliable stall warning signal in practical use, these effects must be carefully examined.
Micromechanics of a Compressed Fiber Mass
Authors: Alkhagen Mårten , Toll Staffan
Published: July 2007

A theory is presented for the rate modeling of flexible granular solids based on affine average motion of interparticle contacts. We allow contacts to form and break continually but assume the existence of a finite friction coefficient rendering contacts force free as they form or break. The resulting constitutive equations are of the hypoelastic type. A specific model for the deformation of a fiber mass is then developed. The model improves on previous theories for fiber masses in at least two respects: First, it is more general in that it is not restricted to uniaxial compression, although it is restricted to predominantly compressive deformations histories, due to neglect of frictional dissipation. Second, by allowing torsion as well as bending of fibers, this theory covers a larger deformation range. Compression experiments are performed on carded slivers of PA6 fibers under various conditions. The measured response is found to be in close agreement with that predicted by the model.