bluuebunny/crossref_metadata_2025 huggingface dataset:
A Joined‐up Approach to User Participation in Public Services: Strengthening the “Participation Chain”
Authors: Simmons Richard , Birchall Johnston
Published: May 2005

Participation has emerged as a key theme for social policy and administration in the UK. Public service providers are often keen to consult users, and users themselves want to make their voices heard. Despite this, however, there is a perennial problem in getting people to participate, and participation is often better supported in principle than in practice. The motivations of key actors are crucial, but are often poorly understood. This article attempts to build a more detailed understanding of the motivations to participate of one key group: service users. Using Mutual Incentives Theory, it shows the extent to which users are motivated by individualistic or collectivistic concerns. These “demand side” factors are then combined with others on the “supply side” in a model we call the “participation chain”. This model provides a systematic framework for understanding what makes public service users participate, and seeks to demonstrate that, while the question of participation requires a combination of answers, it is a combination that can be predicted, planned for and acted upon.
The Clash of Voices: Community‐based Targeting of Safety‐net Interventions in Malawi
Authors: Chinsinga Blessings
Published: May 2005

Using the principle of community targeting, the 2003 Winter Targeted Input Programme was designed to extend free inputs to about 400,000 households in rural Malawi on the basis of access to dambo, and poverty status. The tendency for most communities was, however, to modify the stipulated criteria on the basis of their perceptions and interpretations of need, entitlement and equity. Strikingly, even though the resulting criteria often reflected priorities conflicting with the officially prescribed guidelines, they were nevertheless not necessarily motivated by fraudulent intentions, though there were some isolated cases of ill‐intention. This article therefore advocates at least the incorporation of views from below in the design of interventions of this nature in order to ensure that they achieve the overall desired strategic impact.
Weeping and Transformations of Self
Authors: BARBALET JACK
Published: May 2005

All relevant sources agree that weeping is a human universal. There is disagreement, though, as to whether tears experienced during episodes of happiness or joy derive from the experience of joy itself, or whether such tears result merely from incidental physical constriction of the lacrimal gland (Darwin [1872]) or from a “sadness rebound” induced by anticipated loss of the source of joy (Feldman [1956]; Katz [1999]). It is argued here that adult weeping does not exclusively express suffering but rather is an emotional and physical register of changes in self, both positive and negative. In outlining the argument concerning weeping the paper also presents an account of the registration and consolidation of changes in self‐identity and self‐feelings, and therefore provides an account of the internal process of transformation of self.
Taking a Position: A Reinterpretation of the Theory of Planned Behaviour
Authors: COOK ANDREW J. , MOORE KEVIN , STEEL GARY D.
Published: May 2005

This paper examines methodological issues associated with the theory of planned behaviour and explains that an alternative account of data used to support this theory can be provided by positioning theory. A case is presented that shows tests of the theory of planned behaviour fail to eliminate the possibility of alternative explanations for co‐variation in its data. An agency or person‐centered alternative shows how a causal interpretation can be reinterpreted as evidence of the actions of a person. Unlike the conceptualisation of the individual as behaving in keeping with postulated underlying cognitive laws or rules we assume that the person has, through socialisation, acquired the skills necessary to initiate and manage their own actions. Unlike the interest in TPB data as a causal explanation of action we draw attention to the interpretation of patterns in these data as an aggregate of each person using a common mode of explanation to justify and explain their intentions.
Fear of the Dead as a Factor in Social Self‐Organization
Authors: NAZARETYAN AKOP P.
Published: May 2005

The image of dead person returning to life was the most ancient source of irrational fear (i.e. fear not caused by objective menace) appeared in culture. This conclusion is argued with empirical data from archeology and ethnography. Fear has been expressed in funeral rites, the tying of extremities, burning and dismemberment of dead bodies, and ritual cannibalism (compensatory necrophilia) etc. At the same time, it was attended by effective care for helpless cripples, which seems to descend to the Lower Paleolithic as well. Dread of posthumous revenge played a decisive regulative role at the earliest stage of anthropogenesis, as the disparity between artificial weapons (the tools) and natural aggression‐retention mechanisms (the instincts) became self‐destructive. In the new conditions, individuals with normal animal mind were doomed to catastrophe. Those hominid groups proved viable, in which mystical fear, a product of unnaturally developed imagination, bounded lethal conflicts among kinsmen. The phobias corresponded to the psycho‐nervous system's “strategic pathology”; that was a condition for early hominids’ self‐preservation. As a result, a causal connection between instrumental potential, cultural regulation quality and social sustainability (the techno‐humanitarian balance law) was formed, which has been a mechanism of social selection for all of human history and prehistory.
Deviant Action and Self‐Narration: A Qualitative Survey through ATLAS.ti
Authors: PATRIZI PATRIZIA
Published: May 2005

This paper has its roots in qualitative analysis of accounts produced by an Italian serial killer. Theoretical references are related to symbolic interactionism and its developments in the field of psychology and criminology. The whole contribution is aimed to twofold purposes: A) to provide a set of criteria specifically addressed to study deviant action as system of meanings into two related contexts: the single action itself and the whole life history. According this point, paper introduces the concept of “deviant career” and it explains its development and steps; it also provides some psychological social points of views and contributions that scientific works offers. B) to think about potentialities of accounting interviews as powerful tools in clinical practice and empirical research too.

Specifically, we discuss narrative about behaviour and life story as a resource in order to take suggestions about meanings, goals and rules of action. It also suggests something about functions that crime discharges in the whole pathway of one's life. Juridical case analysis, run by means of the software ATLAS.ti, is aimed to demonstrate theoretical reasoning proposed.
The Narrative Self
Authors: VOLLMER FRED
Published: May 2005

The aim of the present study is to evaluate the postmodern belief that selves are narrative constructions. Four theories, varying in degree of anti‐realism, are presented and discussed. It is concluded that an attractive feature of the narrative approach is that it explains how we achieve a sense of unity. But the main idea, that selves are constituted or created by stories is problematic, like identifying footprints on the beach with the feet that made them.
Presidential Decision Making: Rationality, Advisory Systems, and Personality
Authors: PFIFFNER JAMES P.
Published: May 2005

The authors in this special issue of Presidential Studies Quarterly draw on a rich heritage of decision‐making analysis in the scholarly literature, much of it in the discipline of political science. Over the past several decades, scholars have approached the understanding of presidential decision making from a range of perspectives. The articles in this issue are rich in theory, strong in empirical evidence, and often prescriptive, explicitly or by implication. This introduction will briefly characterize some of the relevant research, contrast two decisions central to George W. Bush's presidency, and then introduce the articles and their contributions to our understanding of presidential decision making.
The Neutral/Honest Broker Role in Foreign‐Policy Decision Making: A Reassessment
Authors: BURKE JOHN P.
Published: May 2005

This article examines the impact of the “neutral” or “honest” broker role in presidential decision making, particularly as applied to the job of National Security Council adviser. It provides further evidence of the positive and continuing contribution of the role to effective decision making, which has been expressed both in theory (Alexander George's formulation of the related concept of the “managerial custodian” in the 1970s) and in practice (the broker role of the Eisenhower‐era NSC special assistants). At the same time, it considers the feasibility of additional tasks such as policy advocacy, public visibility, political watchdog, and operational assignments, which have been embraced, to varying degrees, by more recent NSC advisers but were largely absent in the Eisenhower era and rejected by George as appropriate to the custodian role. The article also examines the applicability of the broker role in light of differing presidential decision‐making needs, different advisory structures, and the issue of bureaucratic leverage and personal influence. Attention to the broker role remains relevant not only in understanding classic decision failures (the expansion of troop commitments in Vietnam in 1965) and successes (Indochina in 1954) but in gaining perspective on more recent decisions, such as Iran‐Contra during the Reagan years and the invasion of Iraq in 2003 and issues surrounding its postwar reconstruction in the George W. Bush presidency.
Neustadt, New Institutionalism, and Presidential Decision Making: A Theory and Test
Authors: DICKINSON MATTHEW J.
Published: May 2005

The institutionalization of a White House‐centered presidential staff system is often described as a logical response by presidents to increasing leadership demands linked to the post‐World War II growth in government size and complexity. In contrast, I take a supply‐side perspective, using transaction‐cost theory and insights from Richard Neustadt'sPresidential Powerto argue that staff growth reflects successive presidents’ search for information and expertise with which to reduce bargaining uncertainty. Once institutionalized, however, staff must be managed. Again building on Neustadt's and new institutionalist insights, I find evidence that presidents using redundant staff structures and competitive staff practices perform more effectively during foreign‐policy crises. The findings suggest potential pitfalls with the “standard” staff model in use today.
Foreign‐Policy Advising: Models and Mysteries from the Bush Administration
Authors: HANEY PATRICK J.
Published: May 2005

There is a wide range of scholarly approaches to studying presidents, advisers, and foreign‐policy making, all aiming to capture the genesis of policy, the “essence of decision.” While we have made some progress in capturing the complexity of how presidents construct foreign‐policy advisory processes, and the kinds of ways they wield power so as to control the policy process, our conceptual models may not be keeping up with practice. While a range of theories exists to explain foreign‐policy cases of a variety of types, and may do so in discrete ways, we are less able to come to terms with how the foreign‐policy process can be both open to a vast range of forces from inside and outside the White House and dominated by the president using unilateral mechanisms of power all at the same time. I use U.S. policy toward Cuba and in Iraq during the first administration of George W. Bush to illustrate this empirical challenge to our conceptual models.
“Micromanagement” of the U.S. Aid Budget and the Presidential Allocation of Attention
Authors: McKEOWN TIMOTHY J.
Published: May 2005

How presidents allocate their attention is the subject of much popular commentary and speculation, but little systematic scholarly research. I focus on an apparent case of presidential “micromanagement”—the practice within the Kennedy, Johnson, and Nixon White Houses of requiring presidential approval for small (often $5 to $10 million) foreign aid expenditures. I sketch the outlines of a theory of presidential attention, and show that the degree of presidential attention to such expenditures is a function of the changing balance of payments position of the United States, and officials’ assessment of the severity of the Soviet threat in the less developed world.
The Structure of Leadership: Presidents, Hierarchies, and Information Flow
Authors: RUDALEVIGE ANDREW
Published: May 2005

This article draws on various theories of organization and hierarchy to argue that presidential staff may be conceived as a necessary limiting structure on an otherwise chaotic informational environment. As such, the shape of that structure shapes the kind, caliber, and amount of information presidents receive on policy matters. Melding classic organization theory and recent formal work with earlier hypotheses about staff effectiveness, I argue that informational institutions centered on functional rather than specific policy lines will best serve the president, and that parallel processing and other monitoring mechanisms will also help the president obtain good advice. Evidence from the Truman, Reagan, and Bush II administrations is used to illustrate this theory and sketch a more systematic research agenda.
The Law: Textbooks and the President's Constitutional Powers
Authors: ADLER DAVID GRAY
Published: May 2005

For many college students, enrollment in an introductory course on American government and politics will constitute their only detailed orientation to U.S. constitutional principles. What they read in introductory textbooks about presidential power will significantly inform and shape their understanding of the authority wielded by the nation's chief executive. How do introductory texts portray the president's constitutional powers? This essay argues that textbooks pay insufficient attention to the source and limits of presidential authority. Moreover, descriptions of executive powers are apt to leave students in a state of confusion. In view of all this, students as citizens are ill‐equipped to assess and evaluate sweeping assertions of executive power. As a consequence, it will be difficult for citizens to check presidential abuses of power.
The Polls: Religion and the 2000 Presidential Election: Public Attitudes Toward Joseph Lieberman
Authors: COHEN JEFFREY E.
Published: May 2005

For the first time since 1960, the religion of candidates for national office became an election issue as Al Gore named Joseph Lieberman, a Jewish senator from Connecticut, to be his vice presidential running mate. Polls over the past forty years have indicated a greater willingness of Americans to vote for nontraditional candidates for major national office, but these expressed opinions have remained purely hypothetical. With Lieberman's candidacy, we can test whether attitudes toward Jews affected support for Lieberman's vice presidential candidacy. Reviewing a variety of polls, but focusing on the 2000 American National Election Study, I find that attitudes toward Jews affect feelings toward Lieberman. Importantly, the American public appeared warmly disposed toward both Jews and Lieberman. Further, being a member of a group which research on anti‐Semitism has identified as at times displaying anti‐Semitic attitudes fails to affect attitudes toward Lieberman. Rather, basic political orientations, such as partisanship and ideology, more strongly affect attitudes toward Lieberman. The liberalization in public opinion about who is qualified to serve as president appears a true phenomenon and not merely the expression of socially acceptable responses to survey questions.
Influence of elastin on rat small artery mechanical properties
Authors: González José M. , Briones Ana M. , Starcher Barry , Conde M. Victoria , Somoza Beatriz , Daly Craig , Vila Elisabet , McGrath Ian , González M. Carmen , Arribas Silvia M.
Published: May 2005

We have previously developed a method for estimating elastin content and organization in resistance arteries, where it is a minor component. The aim of the present study was to validate the method against a quantitative assay and to determine the relative importance of elastin content and organization for intrinsic elasticity of small arteries. Mesenteric third order branches (from 10‐day‐old, 1‐ and 6‐month‐old rats) and middle cerebral arteries (from 6‐month‐old rats) were pressurized. β‐Values were calculated from stress–strain relationships and used as indicators of intrinsic stiffness. The same pressure‐fixed arteries were used to estimate elastin content and organization in the internal elastic lamina with confocal microscopy. Collagen and elastin contents were determined by Picrosirius Red staining and radioimmunoassay for desmosine, respectively. Confocal and desmosine assays gave similar results: no difference in elastin content of mesenteric vessels from 1‐ and 6‐month‐old rats, and a significant reduction in cerebral compared to mesenteric arteries. For all parameters (elastin and collagen content, fenestrae area and internal elastic lamina thickness) the best correlation was found between β‐values and fenestrae size. These data suggest that in small arteries: (1) confocal microscopy can be used as a method for the simultaneous study of changes in elastin content and organization; and (2) elastin organization might be a key determinant of intrinsic elastic properties.
Intracellular mechanisms involved in vascular remodelling of resistance arteries in hypertension: role of angiotensin II
Authors: Touyz Rhian M.
Published: May 2005

Resistance arteries undergo structural changes (vascular remodelling) in hypertension. These changes involve media thickening, reduced lumen diameter and consequent increased media:lumen ratio. Cellular processes underlying these events include altered vascular smooth muscle cell (VSMC) growth, migration, differentiation and increased extracellular matrix abundance. Another factor contributing to remodelling is inflammation, associated with macrophage infiltration, fibrosis and increased expression of redox‐sensitive pro‐inflammatory genes. Among the factors involved in arterial remodelling, angiotensin (Ang) II appears to be one of the most important. Ang II, a multifunctional peptide with pleiotropic actions, modulates vasomotor tone, cell growth, apoptosis/anoikis, cell migration and extracellular matrix deposition. It is pro‐inflammatory and it stimulates production of growth factors and vasoactive agents. The multiple actions of Ang II are mediated via complex intracellular signalling pathways including stimulation of the phosholipase C (PLC)–inositol 1,4,5‐trisphosphate (IP3)−1,2‐diacylglycerol (DAG) cascade, mitogen‐activated protein (MAP) kinases, tyrosine kinases and RhoA/Rho kinase. Furthermore, Ang II elicits many of its (patho)physiological effects by stimulating reactive oxygen species (•O2− and H2O2) generation through activation of vascular NAD(P)H oxidase. •O2− and H2O2 in turn influence downstream signalling molecules including transcription factors, tyrosine kinases/phosphatases, Ca2+ channels and MAP kinases. Interaction between these systems is complex and dysregulation at any level may contribute to vascular remodelling. Targeting such molecules/pathways could prevent or induce regression of hypertensive vascular damage thereby ameliorating development of hypertension and preventing target organ damage. The present review discusses the role of Ang II in remodelling of resistance arteries, focusing on some signalling pathways involved in vascular growth and inflammation in hypertension.
Autonomic nervous system influence on arterial baroreflex control of heart rate during exercise in humans
Authors: Ogoh Shigehiko , Fisher James P. , Dawson Ellen A. , White Michael J. , Secher Niels H. , Raven Peter B.
Published: May 2005

A combination of sympathoexcitation and vagal withdrawal increases heart rate (HR) during exercise, however, their specific contribution to arterial baroreflex sensitivity remains unclear. Eight subjects performed 25 min bouts of exercise at a HR of 90, 120, and 150 beats min−1, respectively, with and without metoprolol (0.16 ± 0.01 mg kg−1; mean ±s.e.m.) or glycopyrrolate (12.6 ± 1.6 μg kg−1). Carotid baroreflex (CBR) function was determined using 5 s pulses of neck pressure (NP) and neck suction (NS) from +40 to −80 Torr, while transfer function gain (GTF) was calculated to assess the linear dynamic relationship between mean arterial pressure and HR. Spontaneous baroreflex sensitivity (SBR) was evaluated as the slope of sequences of three consecutive beats in which systolic blood pressure and the R–R interval of the ECG either increased or decreased, in a linear fashion. The β‐1 adrenergic blockade decreased and vagal cardiac blockade increased HR both at rest and during exercise (P< 0.05). The gain at the operating point of the modelled reflex function curve (GOP) obtained using NP and NS decreased with workload independent of β‐1 adrenergic blockade. In contrast, vagal blockade decreasedGOPfrom −0.40 ± 0.04 to −0.06 ± 0.01 beats min−1mmHg−1at rest (P< 0.05). Furthermore, as workload increased bothGOPand SBR, andGOPandGTFwere correlated (P< 0.001), suggesting that the two dynamic methods applied to evaluate arterial baroreflex (ABR) function provide the same information as the modelledGOP. These findings suggest that during exercise the reduction of arterial baroreceptor reflex sensitivity at the operating point was a result of vagal withdrawal rather than an increase in sympathetic activity.
Inspiratory phase‐locked alpha oscillation in human olfaction: source generators estimated by a dipole tracing method
Authors: Masaoka Yuri , Koiwa Nobuyoshi , Homma Ikuo
Published: May 2005

Olfactory perception and related emotions are largely dependent on inspiration. We acquired simultaneous respiration and electroencephalographic recordings during pleasant odour and unpleasant odour stimulation. We sought to identify changes in respiratory pattern, inspiratory‐related potentials and location of dipoles estimated from the potentials. Electroencephalographic recording was triggered by inspiration onset. Respiratory frequency decreased at pleasant odour recognition, and it increased at unpleasant odour detection and recognition. O2 consumption records showed that these changes were not due to metabolic demand. During olfactory stimulation, inspiratory phase‐locked alpha oscillation (I‐α) was found in the averaged potential triggered by inspiration onset. I‐α was observed at both pleasant odour and unpleasant odour detection and recognition, but it was not seen in the inspiration‐triggered potentials of normal air breathing. Electroencephalographic dipole tracing identified the location of dipoles from the I‐α in the limbic area and the cortex; the entorhinal cortex, hippocampus, amygdala, premotor area and centroposterior orbitofrontal cortex subserve odour detection, and the rostromedial orbitofrontal cortex subserves odour recognition. We suggest that the I‐α in our study originated from the olfactory cortex in the forebrain and was phase‐locked to inspiration.
NaPi‐IIa and interacting partners
Authors: Hernando N. , Gisler S. M. , Pribanic S. , Déliot N. , Capuano P. , Wagner C. A. , Moe O. W. , Biber J. , Murer H.
Published: May 2005

Regulation of renal proximal tubular reabsorption of phosphate (Pi) is one of the critical steps in Pi homeostasis. Experimental evidence suggests that this regulation is achieved mainly by controlling the apical expression of the Na+‐dependent Pi cotransporter type IIa (NaPi‐IIa) in proximal tubules. Only recently have we started to obtain information regarding the molecular mechanisms that control the apical expression of NaPi‐IIa. The first critical observation was the finding that truncation of only its last three amino acid residues has a strong effect on apical expression. A second major finding was the observation that the last intracellular loop of NaPi‐IIa contains sequence information that confers parathyroid hormone (PTH) sensitivity. The use of the above domains of the cotransporter in yeast two‐hybrid (Y2H) screening allowed the identification of proteins interacting with NaPi‐IIa. Biochemical and morphological, as well as functional, analyses have allowed us to obtain insights into the physiological roles of such interactions, although our present knowledge is still far from complete.
Expression and function of dipeptidyl‐aminopeptidase‐like protein 6 as a putative β‐subunit of human cardiac transient outward current encoded by Kv4.3
Authors: Radicke Susanne , Cotella Diego , Graf Eva Maria , Ravens Ursula , Wettwer Erich
Published: May 2005

Dipeptidyl‐aminopeptidase‐like protein 6 (DPPX) was recently shown in the brain to modulate the kinetics of transient A‐type currents by accelerating inactivation and recovery from inactivation. Since the kinetics of human cardiac transient outward current (Ito) are not mimicked by coexpression of the α‐subunit Kv4.3 with its known β‐subunit KChIP2, we have tested the hypothesis that DPPX may serve as an additional β‐subunit in the human heart. With quantitative real‐time RT‐PCR strong mRNA expression of DPPX was detected in human ventricles and was verified at the protein level in human but not in rat heart by a DPPX‐specific antibody. Co‐expression of DPPX with Kv4.3 in Chinese hamster ovary cells produced Ito‐like currents, but compared with expression of KChIP2a and Kv4.3, the time constant of inactivation was faster, the potential of half‐maximum steady‐state inactivation was more negative and recovery from inactivation was delayed. Co‐expression of DPPX in addition to Kv4.3 and KChIP2a produced similar current kinetics as in human ventricular myocytes. We therefore propose that DPPX is an essential component of the native cardiac Ito channel complex in human heart.
Comparative gene expression profile of mouse carotid body and adrenal medulla under physiological hypoxia
Authors: Ganfornina M. D. , Pérez‐García M. T. , Gutiérrez G. , Miguel‐Velado E. , López‐López J. R. , Marín A. , Sánchez D. , González C.
Published: May 2005

The carotid body (CB) is an arterial chemoreceptor, bearing specialized type I cells that respond to hypoxia by closing specific K+ channels and releasing neurotransmitters to activate sensory axons. Despite having detailed information on the electrical and neurochemical changes triggered by hypoxia in CB, the knowledge of the molecular components involved in the signalling cascade of the hypoxic response is fragmentary. This study analyses the mouse CB transcriptional changes in response to low PO2 by hybridization to oligonucleotide microarrays. The transcripts were obtained from whole CBs after mice were exposed to either normoxia (21% O2), or physiological hypoxia (10% O2) for 24 h. The CB transcriptional profiles obtained under these environmental conditions were subtracted from the profile of control non‐chemoreceptor adrenal medulla extracted from the same animals. Given the common developmental origin of these two organs, they share many properties but differ specifically in their response to O2. Our analysis revealed 751 probe sets regulated specifically in CB under hypoxia (388 up‐regulated and 363 down‐regulated). These results were corroborated by assessing the transcriptional changes of selected genes under physiological hypoxia with quantitative RT‐PCR. Our microarray experiments revealed a number of CB‐expressed genes (e.g. TH, ferritin and triosephosphate isomerase) that were known to change their expression under hypoxia. However, we also found novel genes that consistently changed their expression under physiological hypoxia. Among them, a group of ion channels show specific regulation in CB: the potassium channels Kir6.1 and Kcnn4 are up‐regulated, while the modulatory subunit Kcnab1 is down‐regulated by low PO2 levels.
Cytosolic Cl− ions in the regulation of secretory and endocytotic activity in melanotrophs from mouse pituitary tissue slices
Authors: Turner Jan‐Eric , Sedej Simon , Rupnik Marjan
Published: May 2005

Cl− ions are known regulators of Ca2+‐dependent secretory activity in many endocrine cells. The suggested mechanisms of Cl− action involve the modulation of GTP‐binding proteins, voltage‐activated calcium channels or maturation of secretory vesicles. We examined the role of cytosolic Cl− ([Cl−]i) and Cl− currents in the regulation of secretory activity in mouse melanotrophs from fresh pituitary tissue slices by using the whole‐cell patch‐clamp. We confirmed that elevated [Cl−]i augments Ca2−‐dependent exocytosis and showed that Cl− acts on secretory vesicle maturation. The latter process was abolished by a V‐type H−‐ATPase blocker (bafilomycin), intracellular 4,4′‐diisothiocyanatostilbene‐2,2′‐disulphonic acid (DIDS), a Cl− channel blocker, and tolbutamide, a sulphonylurea implicated in secretory vesicle maturation. In a small subset of cells, block of plasmalemmal Cl− current by DIDS reversibly enhanced endocytosis. The direct activation of G‐proteins by GTP‐γ‐S, a non‐hydrolysable GTP analogue, did not restore the impaired secretion observed in low [Cl−]i conditions. The amplitude of voltage‐activated calcium currents was unaffected by the [Cl−]i. Furthermore, two Cl−‐permeable channels, calcium‐activated Cl− channels and GABAA receptors, appeared as major regulators of intracellular Cl− homeostasis. In conclusion, the predominant underlying mechanism of Cl− action is mediated by intracellular Cl− fluxes during vesicle maturation, rather than activation of G‐proteins or modulation of voltage‐activated Ca2+ channels.
ERK1/2 and p38 regulate trophoblasts differentiation in human term placenta
Authors: Daoud Georges , Amyot Marc , Rassart Éric , Masse André , Simoneau Lucie , Lafond Julie
Published: May 2005

Mitogen‐activated protein kinases (MAPKs) control many cellular events from complex programmes, such as embryogenesis, cell differentiation and proliferation, and cell death, to short‐term changes required for homeostasis and acute hormonal responses. However, little is known about expression and activation of classical MAPKs, extracellular signal‐regulated kinase1/2 (ERK1/2) and p38 in human placenta. Therefore, we examined the expression of ERK1/2 and p38 in trophoblasts from human term placenta, and their implication in differentiation. In vitro, freshly isolated cytotrophoblast cells, cultivated in 10% fetal bovine serum (FBS), spontaneously aggregate and fuse to form multinucleated cells that phenotypically resemble mature syncytiotrophoblasts, that concomitantly produce human chorionic gonadotropin (hCG) and human placental lactogen (hPL). This study shows that the level of ERK1/2 and p38 decreases with increasing days of culture, to reach an undetectable level after 5 days of culture. Moreover, pretreatment of cells with an ERK1/2‐specific inhibitor (PD98059) and/or a p38‐specific inhibitor (SB203580) suppressed trophoblast differentiation. Our results also demonstrate that the p38 pathway is highly solicited as compared to the ERK1/2 pathway in the differentiation process. Furthermore, ERK1/2 and p38 are rapidly activated upon addition of FBS, but the activation of p38 is delayed compared to that of ERK1/2. In summary, this study showed that ERK1/2 and p38 pathways are essential to mediate initiation of trophoblast differentiation.
A simple and inexpensive electronic wavelength-meter using a dual-output photodiode
Authors: Roy Sanjukta , Chaudhuri Saptarishi , Unnikrishnan C. S.
Published: May 2005

In this Note we describe the design, construction, and calibration of an electronic wavelength-meter using a wavelength-sensitive dual-output photodiode. The device was constructed using electronic circuitry and then calibrated using various laser sources in the wavelength range 500–850 nm. This is an inexpensive device compared to the other similar devices available commercially. It is very useful for the determination of the wavelengths of diode lasers. It works well with multi-mode light, and there are no stringent alignment requirements. It is extremely compact and essentially a “pocket wavemeter.” The wavelength range for the operation of the wavelength-meter is 450 to 900 nm and it gives 1–3 nm accuracy, depending on the wavelength.
CageLab: A low-cost apparatus to demonstrate rotational motion for advanced undergraduates
Authors: Sahyun Steven C. , Siemens Philip J.
Published: May 2005

CageLab is an inexpensive, easily constructed apparatus for studying rotational motion that was designed as a central example for a unit in our junior-year curriculum. It consists of a rotor suspended so that the direction of its axis is either constrained or approximately free to move through an interesting range of orientations. The rotor’s simple construction from wire mesh (a rectangular cage), modeling clay (used to break the cage’s symmetry), and a detachable axle with simple bearings allows students to quantitatively compute its inertial properties starting from their own measurements of lengths and masses. The pendulum-like fixed suspension facilitates observations of the center-of-mass location and inertial moments. The trapeze-like mobile suspension allows observations of motion with spin along nearly arbitrary axes including stable, neutral, and unstable principal axes without using an expensive gimbal. Removing the clay leaves a symmetric rotor for which gravity-induced precession and nutation can be studied.
Spaceship with a thruster—one body, one force
Authors: Dudley Scott C. , Serna Mario A.
Published: May 2005

A spaceship with one thruster that produces a constant magnitude force is analyzed for various initial conditions. This elementary problem, with one object acted upon by one force, challenges our physical intuition and demonstrates the benefits and limitations of dimensional analysis. The problem also can serve as an introduction to special functions, provide a mechanical model for Fresnel integrals and the associated Cornu spiral, and be used as an example in a numerical methods course.
Numerical simulation of the double slit interference with ultracold atoms
Authors: Gondran Michel , Gondran Alexandre
Published: May 2005

We present a numerical simulation of the double slit interference experiment realized by F. Shimizu, K. Shimizu and H. Takuma with ultracold atoms. We show how the Feynman path integral method enables the calculation of the time-dependent wave function. Because the evolution of the probability density of the wave packet just after it exits the slits raises the issue of interpreting the wave/particle dualism, we also simulate trajectories in the de Broglie–Bohm interpretation.
Use of a CD as a dispersive element in a tunable dye laser
Authors: Khare Rajeev
Published: May 2005

A compact disk is used as a dispersive element for spectral narrowing and wavelength tuning in a tunable narrow-band dye laser. The performance of the laser with the compact disk is evaluated and compared with a similar laser system using a research grade diffraction grating.
Ballistic trajectory: Parabola, ellipse, or what?
Authors: Burko Lior M. , Price Richard H.
Published: May 2005

Mechanics texts tell us that a particle in a bound orbit under a gravitational central force moves in an ellipse, while introductory physics texts approximate the earth as flat, and tell us that the particle moves in a parabola. The latter is meant to be an approximation to a small segment of the true central-force/elliptical orbit. To look more deeply into this connection, we convert earth-centered polar coordinates to “flat-earth coordinates” by treating radial lines as vertical and by treating lines of constant radial distance as horizontal. We consider questions such as whether gravity is purely vertical in this picture, and whether the central force nature of gravity is important only when the height or range of a ballistic trajectory is comparable to the earth’s radius. Somewhat surprisingly, the answers to both questions are “no,” and therein lie some interesting lessons.
Understanding Popper’s experiment
Authors: Qureshi Tabish
Published: May 2005

An experiment proposed by Karl Popper is considered by many to be a crucial test of quantum mechanics. Although many loopholes in the original proposal have been pointed out, they are not crucial to the test. We use only the standard interpretation of quantum mechanics to point out what is fundamentally wrong with the proposal, and demonstrate that Popper’s basic premise was faulty.
Shor’s factoring algorithm and modern cryptography. An illustration of the capabilities inherent in quantum computers
Authors: Gerjuoy Edward
Published: May 2005

The security of messages encoded via the widely used RSA public key encryption system rests on the enormous computational effort required to find the prime factors of a large number N using classical (conventional) computers. In 1994 Peter Shor showed that for sufficiently large N, a quantum computer could perform the factoring with much less computational effort. This paper endeavors to explain, in a fashion comprehensible to the nonexpert, the RSA encryption protocol; the various quantum computer manipulations constituting the Shor algorithm; how the Shor algorithm performs the factoring; and the precise sense in which a quantum computer employing Shor’s algorithm can be said to accomplish the factoring of very large numbers with less computational effort than a classical computer. It is made apparent that factoring N generally requires many successive runs of the algorithm. Our analysis reveals that the probability of achieving a successful factorization on a single run is about twice as large as commonly quoted in the literature.
Early Asymmetry of Gene Transcription in Embryonic Human Left and Right Cerebral Cortex
Authors: Sun Tao , Patoine Christina , Abu-Khalil Amir , Visvader Jane , Sum Eleanor , Cherry Timothy J. , Orkin Stuart H. , Geschwind Daniel H. , Walsh Christopher A.
Published: May 2005

The human left and right cerebral hemispheres are anatomically and functionally asymmetric. To test whether human cortical asymmetry has a molecular basis, we studied gene expression levels between the left and right embryonic hemispheres using serial analysis of gene expression (SAGE). We identified and verified 27 differentially expressed genes, which suggests that human cortical asymmetry is accompanied by early, marked transcriptional asymmetries.
LMO4
is consistently more highly expressed in the right perisylvian human cerebral cortex than in the left and is essential for cortical development in mice, suggesting that human left-right specialization reflects asymmetric cortical development at early stages.
Climate Change and Distribution Shifts in Marine Fishes
Authors: Perry Allison L. , Low Paula J. , Ellis Jim R. , Reynolds John D.
Published: May 2005

We show that the distributions of both exploited and nonexploited North Sea fishes have responded markedly to recent increases in sea temperature, with nearly two-thirds of species shifting in mean latitude or depth or both over 25 years. For species with northerly or southerly range margins in the North Sea, half have shown boundary shifts with warming, and all but one shifted northward. Species with shifting distributions have faster life cycles and smaller body sizes than nonshifting species. Further temperature rises are likely to have profound impacts on commercial fisheries through continued shifts in distribution and alterations in community interactions.
Enols Are Common Intermediates in Hydrocarbon Oxidation
Authors: Taatjes Craig A. , Hansen Nils , McIlroy Andrew , Miller James A. , Senosiain Juan P. , Klippenstein Stephen J. , Qi Fei , Sheng Liusi , Zhang Yunwu , Cool Terrill A. , Wang Juan , Westmoreland Phillip R. , Law Matthew E. , Kasper Tina , Kohse-Höinghaus Katharina
Published: May 2005

Models for chemical mechanisms of hydrocarbon oxidation rely on spectrometric identification of molecular structures in flames. Carbonyl (keto) compounds are well-established combustion intermediates. However, their less-stable enol tautomers, bearing OH groups adjacent to carbon-carbon double bonds, are not included in standard models. We observed substantial quantities of two-, three-, and four-carbon enols by photoionization mass spectrometry of flames burning representative compounds from modern fuel blends. Concentration profiles demonstrate that enol flame chemistry cannot be accounted for purely by keto-enol tautomerization. Currently accepted hydrocarbon oxidation mechanisms will likely require revision to explain the formation and reactivity of these unexpected compounds.
Tubulin Polyglutamylase Enzymes Are Members of the TTL Domain Protein Family
Authors: Janke Carsten , Rogowski Krzysztof , Wloga Dorota , Regnard Catherine , Kajava Andrey V. , Strub Jean-Marc , Temurak Nevzat , van Dijk Juliette , Boucher Dominique , van Dorsselaer Alain , Suryavanshi Swati , Gaertig Jacek , Eddé Bernard
Published: May 2005

Polyglutamylation of tubulin has been implicated in several functions of microtubules, but the identification of the responsible enzyme(s) has been challenging. We found that the neuronal tubulin polyglutamylase is a protein complex containing a tubulin tyrosine ligase–like (TTLL) protein, TTLL1. TTLL1 is a member of a large family of proteins with a TTL homology domain, whose members could catalyze ligations of diverse amino acids to tubulins or other substrates. In the model protist
Tetrahymena thermophila
, two conserved types of polyglutamylases were characterized that differ in substrate preference and subcellular localization.
Platelet-activating factor and prostaglandin E2impair esophageal ACh release in experimental esophagitis
Authors: Cheng Ling , Cao Weibiao , Fiocchi Claudio , Behar Jose , Biancani Piero , Harnett Karen M.
Published: May 2005

ACh is a neurotransmitter in cat esophageal circular muscle, as atropine nearly abolishes contraction of in vitro circular muscle strips in response to electric field stimulation (EFS) ( 5 , 12 ). Experimental esophagitis reduced EFS- but not ACh-induced contraction of esophageal circular muscle, suggesting that esophagitis impairs neurotransmitter release. Because IL-1β and IL-6 are produced in esophagitis and reproduce these changes in normal esophageal muscle ( 12 ), we examined the role of IL-1β and IL-6 in this motor dysfunction. IL-1β, IL-6 ( 12 ), H2O2, PGE2, and platelet-activating factor (PAF) were elevated in esophagitis specimens. Normal muscle incubated (2 h) in IL-1β and IL-6 had increases in H2O2, PGE2, and PAF levels. H2O2contributed to increased PGE2and PAF, as the increase was partially (60–80%) reversed by the H2O2scavenger catalase. EFS-induced [3H]ACh release from muscle strips significantly (42%) decreased in esophagitis and after 2 h incubation in PGE2and in PAF C-16. Similarly, EFS-induced but not ACh-induced muscle contraction decreased in esophagitis and after incubation in PGE2and PAF C-16. Finally, in normal muscle strips treated with IL-1β electrical field stimulation (EFS)-induced contraction was partially restored by indomethacin or by the PAF antagonist CV3988 and was completely restored by the combination of CV3988 and indomethacin, whereas in strips treated with IL-6, EFS-induced contraction was partially restored by the PAF antagonist CV3988 and not affected by indomethacin. We conclude that IL-1β-induced production of H2O2causes formation of PGE2and PAF that inhibit ACh release from esophageal cholinergic neurons without affecting ACh-induced contraction of esophageal circular muscle. IL-6 causes production of H2O2, PAF, and other unidentified inflammatory mediators.
No genetic association of the human prolyl endopeptidase gene in the Dutch celiac disease population
Authors: Diosdado Begoña , Stepniak Dariusz T. , Monsuur Alienke J. , Franke Lude , Wapenaar Martin C. , Mearin Maria Luisa , Koning Frits , Wijmenga Cisca
Published: May 2005

Celiac disease (CD) is a complex genetic disorder of the small intestine. The DQ2/DQ8 human leucocyte antigen (HLA) genes explain ∼40% of the genetic component of the disease, but the remaining non-HLA genes have not yet been identified. The key environmental factor known to be involved in the disease is gluten, a major protein present in wheat, barley, and rye. Integrating microarray data and linkage data from chromosome 6q21–22 revealed the prolyl endopeptidase ( PREP) gene as a potential CD candidate in the Dutch population. Interestingly, this gene encodes for the only enzyme that is able to cleave the proline-rich gluten peptides. To investigate the role of the human PREP gene as a primary genetic factor in CD, we conducted gene expression, sequence analysis, and genetic association studies of the PREP gene and determined PREP enzyme activity in biopsies from CD patients and controls. Sequence analysis of the coding region of the PREP gene revealed two novel polymorphisms. Genetic association studies using two novel polymorphisms and three known PREP variants excluded a genetic association between PREP and CD. Determination of PREP activity revealed weak but significant differences between treated and untreated CD biopsies ( P < 0.05). Our results from the association study indicate that PREP is not a causative gene for CD in the Dutch population. These are further supported by the activity determinations in which we observed no differences in PREP activity between CD patients and controls.
Effect of serum triiodothyronine on regulation of cardiac gene expression: role of histone acetylation
Authors: Danzi Sara , Dubon Peter , Klein Irwin
Published: May 2005

Thyroid hormone regulates the transcription of several important cardiac genes. Although the thyroid gland produces predominantly thyroxine (T4), it is triiodothyronine (T3) that is transported across the sarcolemma and binds to nuclear thyroid hormone receptor proteins; yet various studies suggest that serum T3 levels do not accurately reflect cellular T3 action. To address this question, we studied the dose-response relationship of T3 administered by constant infusion in hypothyroid animals with the simultaneous in vivo transcription rate of the cardiac-specific α-myosin heavy chain (MHC) gene, measured by quantitating α-MHC heteronuclear (hn)RNA content. Constant infusion of 4 μg T3·kg body wt−1·day−1 for 3 days normalized serum T3 and restored transcription to euthyroid levels; in contrast, daily injections of the same dose increased α-MHC transcription by only 55% of that obtained by infusion. Although infusion of T3 at 1.25 μg T3·kg body wt−1·day−1 was not sufficient to restore serum T3 to normal, it was capable of restoring transcription to normal at 3 days, but when administered for 12 days, transcription of α-MHC was found to be 50% of euthyroid levels, demonstrating a decreased sensitivity to T3 over time. Treatment with trichostatin A (TSA) to inhibit histone deacetylation increased levels of total nuclear acetylated histone H4 by almost 50% but was without effect on the real-time PCR measures of α-MHC hnRNA. TSA administered together with T3 (10 μg T3/kg body wt) significantly increased transcription of α-MHC after 30 h, thus demonstrating a potential role for histones as cofactors in the T3 regulation of cardiac α-MHC transcription.