bluuebunny/crossref_metadata_2025 huggingface dataset:
Throwing Pebbles into a Dark Cave: A Study of Participation and Behaviour in the {act-km} Online Community
Authors: Timbrell Greg , Lambe Patrick , Taule Ørjan
Published: June 2007

This article defines online communities and their constituent elements. It provides a framework in which online communities can be discussed and compared irrespective of topic or content. It explores the notions of core and peripheral membership and behaviour and provides a set of metrics for determining the activity profile of the community. Finally it presents a case study of an online community and discusses it using the framework and metrics presented.
Knowledge Sharing in a Collaborative Networked Environment
Authors: Cormican Kathryn , Dooley Lawrence
Published: June 2007

Knowledge is a key resource that must be managed within organisations and across collaborative enterprise networks. In particular, the two major challenges that such organisations face are ensuring that they have the appropriate knowledge to support their operations and ensuring that they optimise these knowledge resources available to them. In recent years, researchers, consultants and industrialists have developed approaches in an attempt to address these requirements. Most of these approaches have been technology oriented. In other words, the implementation of information technology systems is seen as the solution to enterprise knowledge management problems. However, research indicates that organisations are still failing to convert individual skills and competencies into tangible products and services. Knowledge management is an emerging discipline and it is still not very well understood or managed in industry. Consequently, new knowledge initiatives are not exploited to their full potential. In other words, companies are not reaping the full benefits of knowledge management projects. This paper explores the key constituents to managing knowledge and examines the main problems with sharing knowledge across teams and organisational boundaries. Findings from a qualitative study suggest that the key problems to managing knowledge across a collaborative network are person centric and consequently managers should focus their efforts on improving critical areas such as motivation and trust as well as people oriented methods and tools.
FACTORS AFFECTING THE USE OF PUBLIC SUPPORT SERVICES BY SME OWNERS: EVIDENCE FROM A PERIPHERY REGION OF CANADA
Authors: AUDET JOSEE , ST-JEAN ETIENNE
Published: June 2007

Public authorities throughout the world, recognizing both the importance and fragility of SMEs, have over the years created agencies and set up numerous venture development support and assistance measures. Despite all these efforts, SME owner-managers do not appear to make maximum use of the services available. Results from a survey of 70 SME owner-managers show that the likelihood of an SME using public support services increases as the perceived usefulness of public agencies and their services increases, and as the level of knowledge of public agencies increases. Furthermore, the probability of using public support services decreases as the experience of the owner-manager increases. On one hand, many owner-managers do not seem to understand the utility or relevance of the services the agencies provide, while on the other, they do not seem to know enough about the agencies working in their region. However, most of the owner-managers who had used the agencies felt the services they had received were appropriate to their needs. Therefore, the problem appears to lie more with the perceptions of certain owner-managers than with the nature or quality of the services themselves.
DOING BUSINESS IN THE TORRES STRAITS: A STUDY OF THE RELATIONSHIP BETWEEN CULTURE AND THE NATURE OF INDIGENOUS ENTREPRENEURS
Authors: LEE-ROSS DARREN , MITCHELL BENJAMIN
Published: June 2007

This qualitative study focuses on the relationship between culture and entrepreneurship in the Torres Strait Islands. Similar to other countries with a low per capita Gross Domestic Product (GDP), aggregate evidence suggests that entrepreneurial activity is commonplace among the indigenous community. Closer investigation revealed this is particularly so for a form known as "marginal" entrepreneurship. Using Hofstede's (1994) model of cultural dimensions linked to key western entrepreneurial traits, a sample of 61 Torres Strait entrepreneurs showed sizable perceptual trait differences compared with western theory. This has implications on the received current wisdom regarding typical values and characteristics of entrepreneurs. It would appear that cultural differences exist between the entrepreneurs of the Torres Straits and others. The implications of this finding have a potentially significant impact on policy and the level and types of investment funds made available for enabling entrepreneurship in the Torres Straits.
FLUCTUATIONS OF SINGLE CONFINED ACTIN FILAMENTS
Authors: KÖSTER SARAH , STARK HOLGER , PFOHL THOMAS , KIERFELD JAN
Published: June 2007

Thermal fluctuations of individual actin filaments confined in rectangular microchannels with dimensions similar to the mesh size of the cytoskeleton in eukaryotic cells are studied experimentally using fluorescence microscopy and theoretically by a combination of analytical methods and Monte Carlo simulations. Compared to freely fluctuating filaments, long filaments confined in narrow channels exhibit enhanced tangent correlations and a characteristic shape of their correlation function. The tangent correlation function is calculated analytically by approximating the confining geometry by a parabolic potential. This approximation is validated by Monte Carlo simulations. For the quantitative analysis of experimental data additional corrections for image analysis effects have to be included, for which we provide a modified analytical approximation formula which is corroborated by simulations. This allows us to obtain both the persistence length LPdescribing the bending rigidity of the polymer and the deflection length λ characterizing confinement effects from fits to the experimental data. Our results confirm the scaling relation λ ∝ d2/3between the deflection length and the channel width d.
SELF-RECOGNITION OF DNA FROM LIFE PROCESSES TO DNA COMPUTATION
Authors: NG WEI DA , WONG CHEE KEONG BENJAMIN
Published: June 2007

Ever since the first appearance of deoxyribose nucleic acid (DNA) in 1953, it has fascinated multitudes with its simplicity. With a modest syllabus of four nucleotides (adenine, thymine, cytosine and guanine), it codes for the complexity of life around us. In this paper, we investigate how the structure of DNA codes for life processes and how we can take advantage of its minuscule size, mechanism of self-recognition and self-assembly for "bottom-up" nanotechnology. High hopes are also placed on miniaturizing present computing technology using DNA computing based on two fundamental features; massive parallelism of DNA strands and Watson–Crick complementarity. Advances in DNA-based computation and algorithmic assembly are then used to complement researches in DNA nanotechnology.
Effect of hypobaric air, oxygen, heliox (50:50), or heliox (80:20) breathing on air bubbles in adipose tissue
Authors: Hyldegaard O. , Madsen J.
Published: June 2007

The fate of bubbles formed in tissues during decompression to altitude after diving or due to accidental loss of cabin pressure during flight has only been indirectly inferred from theoretical modeling and clinical observations with noninvasive bubble-measuring techniques of intravascular bubbles. In this report we visually followed the in vivo resolution of micro-air bubbles injected into adipose tissue of anesthetized rats decompressed from 101.3 kPa to and held at 71 kPa corresponding to ∼2.750 m above sea level, while the rats breathed air, oxygen, heliox (50:50), or heliox (80:20). During air breathing, bubbles initially grew for 30–80 min, after which they remained stable or began to shrink slowly. Oxygen breathing caused an initial growth of all bubbles for 15–85 min, after which they shrank until they disappeared from view. Bubble growth was significantly greater during breathing of oxygen compared with air and heliox breathing mixtures. During heliox (50:50) breathing, bubbles initially grew for 5–30 min, from which point they shrank until they disappeared from view. After a shift to heliox (80:20) breathing, some bubbles grew slightly for 20–30 min, then shrank until they disappeared from view. Bubble disappearance was significantly faster during breathing of oxygen and heliox mixtures compared with air. In conclusion, the present results show that oxygen breathing at 71 kPa promotes bubble growth in lipid tissue, and it is possible that breathing of heliox may be beneficial in treating decompression sickness during flight.
Model of oxygen transport and metabolism predicts effect of hyperoxia on canine muscle oxygen uptake dynamics
Authors: Lai Nicola , Saidel Gerald M. , Grassi Bruno , Gladden L. Bruce , Cabrera Marco E.
Published: June 2007

Previous studies have shown that increased oxygen delivery, via increased convection or arterial oxygen content, does not speed the dynamics of oxygen uptake, V̇o2m, in dog muscle electrically stimulated at a submaximal metabolic rate. However, the dynamics of transport and metabolic processes that occur within working muscle in situ is typically unavailable in this experimental setting. To investigate factors affecting V̇o2mdynamics at contraction onset, we combined dynamic experimental data across working muscle with a mechanistic model of oxygen transport and metabolism in muscle. The model is based on dynamic mass balances for O2, ATP, and PCr. Model equations account for changes in cellular ATPase, oxidative phosphorylation, and creatine kinase fluxes in skeletal muscle during exercise, and cellular respiration depends on [ADP] and [O2]. Model simulations were conducted at different levels of arterial oxygen content and blood flow to quantify the effects of convection and diffusion of oxygen on the regulation of cellular respiration during step transitions from rest to isometric contraction in dog gastrocnemius muscle. Simulations of arteriovenous O2differences and V̇o2mdynamics were successfully compared with experimental data (Grassi B, Gladden LB, Samaja M, Stary CM, Hogan MC. J Appl Physiol 85: 1394–1403, 1998; and Grassi B, Gladden LB, Stary CM, Wagner PD, Hogan MC. J Appl Physiol 85: 1404–1412, 1998), thus demonstrating the validity of the model, as well as its predictive capability. The main findings of this study are: 1) the estimated dynamic response of oxygen utilization at contraction onset in muscle is faster than that of oxygen uptake; and 2) hyperoxia does not accelerate the dynamics of diffusion and consequently muscle oxygen uptake at contraction onset due to the hyperoxia-induced increase in oxygen stores. These in silico derived results cannot be obtained from experimental observations alone.
Cardiac output and leg and arm blood flow during incremental exercise to exhaustion on the cycle ergometer
Authors: Calbet Jose A. L. , Gonzalez-Alonso Jose , Helge Jörn W. , Søndergaard Hans , Munch-Andersen Thor , Boushel Robert , Saltin Bengt
Published: June 2007

To determine central and peripheral hemodynamic responses to upright leg cycling exercise, nine physically active men underwent measurements of arterial blood pressure and gases, as well as femoral and subclavian vein blood flows and gases during incremental exercise to exhaustion (Wmax). Cardiac output (CO) and leg blood flow (BF) increased in parallel with exercise intensity. In contrast, arm BF remained at 0.8 l/min during submaximal exercise, increasing to 1.2 ± 0.2 l/min at maximal exercise ( P < 0.05) when arm O2 extraction reached 73 ± 3%. The leg received a greater percentage of the CO with exercise intensity, reaching a value close to 70% at 64% of Wmax, which was maintained until exhaustion. The percentage of CO perfusing the trunk decreased with exercise intensity to 21% at Wmax, i.e., to ∼5.5 l/min. For a given local V̇o2, leg vascular conductance (VC) was five- to sixfold higher than arm VC, despite marked hemoglobin deoxygenation in the subclavian vein. At peak exercise, arm VC was not significantly different than at rest. Leg V̇o2 represented ∼84% of the whole body V̇o2 at intensities ranging from 38 to 100% of Wmax. Arm V̇o2 contributed between 7 and 10% to the whole body V̇o2. From 20 to 100% of Wmax, the trunk V̇o2 (including the gluteus muscles) represented between 14 and 15% of the whole body V̇o2. In summary, vasoconstrictor signals efficiently oppose the vasodilatory metabolites in the arms, suggesting that during whole body exercise in the upright position blood flow is differentially regulated in the upper and lower extremities.
Giant Cell Arteritis as a Cause of First-Ever Stroke
Authors: Wiszniewska Malgorzata , Devuyst Gerald , Bogousslavsky Julien
Published: June 2007

The aims of this study were to assess how frequently giant cell arteritis (GCA) was a cause of first-ever stroke in 4,086 patients in the Lausanne Stroke Registry and to determine the risk factors, patterns, latency and current therapy at onset in patients with GCA plus stroke. GCA was recognized using the criteria of the American College of Rheumatology. We report on 6 patients (0.15%) with a histologically proven diagnosis of temporal arteritis and clinical and neuroradiological evidence of cerebral ischemia. The CT and MRI scans showed lacunar infarction in 3 patients, territorial infarction in 2 and were normal in 1. Stroke latency ranged from 0 to 2 months. All patients suffered from headache. We conclude that stroke is a rare, but dangerous, complication of GCA and that a combination of antiplatelet drugs and corticosteroids may be advisable for preventing stroke occurrence.
Performance of the ABCD and ABCD2 Scores in TIA Patients with Carotid Stenosis and Atrial Fibrillation
Authors: Koton S. , Rothwell P.M.
Published: June 2007

Background: It has been suggested that scores for risk stratification of TIA patients might not identify patients with carotid stenosis or atrial fibrillation (AF) and that this might undermine the usefulness of such scores. Methods: In patients with TIA in the Oxford Vascular Study, we studied the associations between ABCD and ABCD2 scores, the presence of ≧50% ipsilateral carotid stenosis or AF, and the risk of stroke at 7 days. Results: Among 285 TIA patients (from 559 referrals of possible TIA), 69 (24.2%) had either ≧50% carotid stenosis (n = 29) or AF (n = 42), or both (n = 2). Although the ABCD and ABCD2 scores were highly predictive of stroke at 7 days (p < 0.0001), there was no clear relationship between either score and the prevalence of ≧50% carotid stenosis or AF. However, the scores did predict the 7-day stroke risk in patients with these pathologies: ABCD score (trend – p = 0.05); ABCD2 (trend – p = 0.03). Five of the 6 patients with AF or symptomatic stenosis who had a stroke within 7 days of their TIA had an ABCD score of ≧5 and all 6 had an ABCD2 score of ≧4. Conclusions: The ABCD and ABCD2 risk scores appear to identify patients with ≧50% carotid stenosis or AF who are at high risk of stroke. However, these findings should be interpreted with caution due to the small number of outcomes among these subgroups, and further validations are necessary.
Small-Vessel Vascular Disease in Human Immunodeficiency Virus Infection: The Hawaii Aging with HIV Cohort Study
Authors: McMurtray Aaron , Nakamoto Beau , Shikuma Cecelia , Valcour Victor
Published: June 2007

Background: This study is designed to determine the relationship between age and occurrence of cerebral manifestations of small-vessel ischemic vascular disease in human immunodeficiency virus (HIV)-seropositive individuals. Methods: Periventricular leukoaraiosis severity and white matter lesion volume were determined by magnetic resonance imaging of the brain of 57 HIV-seropositive individuals. Results: Cerebral small-vessel ischemic vascular disease manifestations correlated with age and systolic blood pressure, but not with HIV infection-related parameters. Conclusions: These findings suggest that, in the era of highly active antiretroviral therapy, leukoaraiosis severity and white matter lesion volume may be more indicative of small-vessel ischemic vascular disease than HIV-related CNS pathology, and support the need for aggressive treatment of vascular risk factors in HIV-seropositive individuals.
Quality of Life in Obsessive-Compulsive Disorder: The Different Impact of Obsessions and Compulsions
Authors: Stengler-Wenzke Katarina , Kroll Michael , Riedel-Heller Steffi , Matschinger Herbert , Angermeyer Matthias C.
Published: June 2007

Background: Patients with obsessive-compulsive disorder (OCD) are troubled by repeated obsessions and/or compulsions, which seem senseless and frequently repugnant. Objective: The study examines the differential impact of obsessions and compulsions on the quality of life (QoL) of patients with OCD. Methods: Seventy-five patients (43 females, 32 males) between 21 and 62 years old with OCD (ICD 10 F42.0–F42.2) were recruited from the outpatient clinic for anxiety disorders at the Department of Psychiatry of the University of Leipzig. The severity of OCD symptoms was assessed by the Yale Brown Obsessive-Compulsive Scale (a standardized, clinician-administered scale), and depressiveness was assessed with the Beck Depression Inventory (a self-report instrument). QoL was assessed by means of the WHOQOL-BREF, a self-administered questionnaire developed by WHO. Results: Compulsions reduced patients’ QoL in the WHOQOL-BREF domains ‘physical well-being’, ‘psychological well-being’ and ‘environment’, whereas obsessions did not have any impact on QoL ratings. Depressive symptoms were a strong predictor of poor QoL in OCD patients. Conclusions: In order to judge the QoL of OCD patients, obsessions and compulsions have to be considered differently. Diagnosing and treating depressive symptoms is important for improving the QoL in OCD.
Dyadic Facial Affective Indicators of Severity of Symptomatic Burden in Patients with Panic Disorder
Authors: Benecke Cord , Krause Rainer
Published: June 2007

Background: Based on the results of research on facial affective behaviour in different psychological disorders, as well as on available findings on the specific behaviour of patients with panic disorder in interaction with their therapists, hypotheses about dyadic facial affective behaviour and its correlation with symptomatic burden of female panic patients are formulated. Sampling and Methods: The facial affective behaviour of 20 patients with panic disorder and their therapists, coded with the Emotional Facial Action Coding System, in the first treatment session is analyzed regarding interactive enmeshment, and for a subgroup of 15 dyads these data are correlated with those on symptomatic burden before treatment. Results: A high degree of interactive enmeshment between patient and therapist correlates positively with the severity of symptomatic burden. All dyadic enmeshment indicators show highly significant positive correlations with body-related symptoms, but not with more general variables like global severity index of the SCL-90R or general anxiety (State Trait Anxiety Inventory). Conclusions: These results are discussed against the background of specific psychodynamics of panic patients and show that, on the one hand, therapists practise an interactive abstinence, but on the other hand, they tend to be pulled into a specific interactive enmeshment by patients with greater symptomatic burden. Limitations of the study arise from the small sample and the lack of a comparison group, therefore the question if the results are disorder specific or more general cannot be answered.
Facial Expression and Experience of Emotions in Psychodynamic Interviews with Patients with PTSD in Comparison to Healthy Subjects
Authors: Kirsch Anke , Brunnhuber Stefan
Published: June 2007

Background: The facial affective behavior of traumatized patients and of a healthy control group was compared. Sampling and Methods: Data of 15 videotaped clinical interviews of traumatized inpatients and of 15 healthy women (absence of mental/psychiatric disorder according to ICD-10) were ascertained. The affective facial expression of both groups was coded with the Emotional Facial Acting Coding System. Afterwards, the mimic analysis was correlated with gazing behavior and the emotional experience. The patients reported their traumatic experiences and the healthy women their main complaints. Results: The traumatized patients showed neither a reduction of overall facial expressions nor a reduced frequency of facial affects in comparison to the healthy control group. The control group, however, showed significantly more ‘genuine joy’. The traumatized patients showed significantly more anger. Conclusions: The traumatized patients did not show a significant reduction of overall facial expression. A more detailed analysis showed that on the one hand, stabilizing elements of relationships, such as genuine joy, appear significantly less on the face of traumatized patients as compared with the healthy women. On the other hand, the expression of anger was brought into the relationship significantly more often by the traumatized patients during face-to-face interaction (clinical interview). This indicates the importance of distance regulation interaction patterns of traumatized patients.
An Observing System Simulation Experiment for the Indian Ocean
Authors: Vecchi Gabriel A. , Harrison Matthew J.
Published: June 2007

An integrated in situ Indian Ocean observing system (IndOOS) is simulated using a high-resolution ocean general circulation model (OGCM) with daily mean forcing, including an estimate of subdaily oceanic variability derived from observations. The inclusion of subdaily noise is fundamental to the results; in the mixed layer it is parameterized as Gaussian noise with an rms of 0.1°C; below the mixed layer a Gaussian interface displacement with an rms of 7 m is used. The focus of this assessment is on the ability of an IndOOS—comprising a 3° × 3° Argo profiling float array, a series of frequently repeated XBT lines, and an array of moored buoys—to observe the interannual and subseasonal variability of subsurface Indian Ocean temperature. The simulated IndOOS captures much of the OGCM interannual subsurface temperature variability.

A fully deployed Argo array with 10-day sampling interval is able to capture a significant part of the Indian Ocean interannual temperature variability; a 5-day sampling interval degrades its ability to capture variability. The proposed moored buoy array and frequently repeated XBT lines provide complementary information in key regions, particularly the Java/Sumatra and Somali upwelling and equatorial regions. Since the subdaily noise is of the same order as the subseasonal signal and since much of the variability is submonthly, a 5-day sampling interval does not drastically enhance the ability of Argo to capture the OGCM subseasonal variability. However, as sampling intervals are decreased, there is enhanced divergence of the Argo floats, diminished ability to quality control data, and a decreased lifetime of the floats; these factors argue against attempting to resolve subseasonal variability with Argo by shortening the sampling interval. A moored array is essential to capturing the subseasonal and near-equatorial variability in the model, and the proposed moored buoy locations span the region of strong subseasonal variability. On the whole, the proposed IndOOS significantly enhances the ability to capture both interannual and subseasonal variability in the Indian Ocean.
Wind-Driven Response of the Northern Indian Ocean to Climate Extremes*
Authors: Jensen Tommy G.
Published: June 2007

Composites of Florida State University winds (1970–99) for four different climate scenarios are used to force an Indian Ocean model. In addition to the mean climatology, the cases include La Niña, El Niño, and the Indian Ocean dipole (IOD). The differences in upper-ocean water mass exchanges between the Arabian Sea and the Bay of Bengal are investigated and show that, during El Niño and IOD years, the average clockwise Indian Ocean circulation is intensified, while it is weakened during La Niña years. As a consequence, high-salinity water export from the Arabian Sea into the Bay of Bengal is enhanced during El Niño and IOD years, while transport of low-salinity waters from the Bay of Bengal into the Arabian Sea is enhanced during La Niña years. This provides a venue for interannual salinity variations in the northern Indian Ocean.
A Diagnostic Study of the Indian Ocean Dipole Mode in El Niño and Non–El Niño Years
Authors: Drbohlav Hae-Kyung Lee , Gualdi Silvio , Navarra Antonio
Published: June 2007

The Indian Ocean dipole mode (IODM) is examined by comparing the characteristics of oceanic and atmospheric circulations, heat budgets, and possible mechanisms of IODM between El Niño and non–El Niño years. Forty-year ECMWF Re-Analysis (ERA-40) data, Reynolds SST data, and ocean assimilation data from the Modular Ocean Model are used to form composites of the IODM that occur during El Niño (1972, 1982, and 1997) and non–El Niño (1961, 1967, and 1994) years. In El Niño years, two off-equatorial, anticyclonic circulations develop, associated with the increased pressure over the eastern Indian Ocean. The anticyclonic circulation over the Northern Hemisphere enhances the easterly component of the winds in the northwestern Indian Ocean. This enhanced easterly component increases the mixed layer temperature by inducing an anomalous westward ocean current that advects the warm mean mixed layer from the central to the western Indian Ocean. Meanwhile, the anticyclonic circulation over the southeastern Indian Ocean strengthens southeasterlies, thereby causing oceanic meridional and vertical advection of the cold mean temperature. Consequently, the IODM in El Niño years is characterized by the warming in the northwestern and the cooling in the southeastern Indian Ocean. In non–El Niño years, a monsoonlike wind flow increases the westerly and southeasterly components of the wind over the northwestern and southeastern Indian Ocean, respectively. Oceanic currents induced by these winds result in anomalous cold advection in both of these regions. In addition, the monsoonlike wind flow over the southeastern Indian Ocean enhances the anomalous latent and sensible heat fluxes in non–El Niño years. Hence, the cooling of the eastern tropical Indian Ocean, rather than the warming of the western Indian Ocean, becomes the major feature of the IODM during non–El Niño years.
Modeling the Variability of the Greater Agulhas Current System
Authors: Hermes J. C. , Reason C. J. C. , Lutjeharms J. R. E.
Published: June 2007

An eddy-permitting, regional ocean model has been used to examine the variability in the source regions of the Agulhas Current on a range of time scales. These source regions are the East Madagascar Current, the flow through the Mozambique Channel, and the recirculation of the southwest Indian Ocean. The effect of variability in these source regions on the interocean leakage at the Agulhas retroflection south of Africa has been quantified using a retroflection index.

On the annual mean, the recirculation in the southwest Indian Ocean subgyre is by far the dominant contribution to the volume transport of the Agulhas Current in the model. On average the recirculation also contributes the largest amount of heat, although the difference between the three sources is not as great as that seen in the volume flux since the water in the Mozambique Channel may be warmer than in the recirculation. Local winds seem to be the dominant forcing mechanism of variability in this recirculation, although it is also partly in phase with the zonally averaged wind stress curl over the subtropical Indian Ocean. A strong relationship was found between the transport of the recirculation and that of the Agulhas Current, particularly on interannual time scales.

Consistent with observations, the model flow through the Mozambique Channel is dominated by eddies, with a strong annual cycle, lagging the South Equatorial Current by 1 month and a weaker semiannual cycle. The southern limb of the East Madagascar Current also shows an annual and semiannual variation in transport at 20°S, partly in phase with the local winds. South of about 24°S, the East Madagascar Current breaks up into eddies.

An investigation into the sensitivity of the flows in the source regions and in the retroflection index to a 2° southward shift in the mean winds was conducted. In the model run with the shifted winds, the transport strengthened in the recirculation subgyre together with increased mesoscale activity as well as reduced leakage into the southeast Atlantic Ocean when the winds were shifted south by 2°.
Explorations of the Annual Mean Heat Budget of the Tropical Indian Ocean. Part II: Studies with a Simplified Ocean General Circulation Model
Authors: Hu Rui-Jin , Godfrey J. Stuart
Published: June 2007

Present-day OGCMs give low values of annual mean net heat flux (AMNHF) in the tropical Indian Ocean, compared to climatologies. AMNHF generation is examined in an open-boundary model of this region with realistic coastlines. In the first two of three experiments only annual mean wind stresses were applied so that a modified form of the “minimum depth criterion” of the previous paper would be applicable. Area-integrated AMNHF was well below observed values, despite the fact that western boundary inflow was substantially deeper and colder than was expected from the modified minimum depth estimate. The model showed large “spikes” in the gradient of “depth-integrated steric height” (DISH) along the western boundary, coinciding with coastline steps (which were absent in the previous paper). Most diapycnal entrainment occurred next to the coast, near these steps. In a third experiment a seasonal cycle of wind stress was added to the same annual mean. Annual mean diapycnal mixing and entrainment increased and the western boundary inflow deepened, resulting in substantially greater AMNHF for the same annual mean Ekman transports. However, area-integrated AMNHF was still well below the mean of directly observed surface fluxes. The recirculation around the “Great Whirl” doubled, permitting more cold water crossing the equator in one year to mix with recirculated water generated in a previous year. Entrainment up to the surface thus went by stages, over more than one year. The increased Great Whirl was related to stronger annual mean curls of nonlinear terms in the momentum equation, while the deeper entrainment was caused by stronger annual mean diapycnal mixing. In all experiments, diapycnal mixing was primarily due to the “flux corrected transport” (FCT) advective scheme, which in effect replaces spurious convective overturn by numerical diffusion. More research is needed to solve such problems, but sensitivity of AMNHF in OGCMs to time-varying forcing—due to seasonal, intraseasonal, or baroclinic instability—may offer a new source of climate predictability.
Modeling Decadal Changes on the Indian Ocean Section I5 at 32°S
Authors: Murray R. J. , Bindoff Nathaniel L. , Reason C. J. C.
Published: June 2007

A near-global ocean model with resolution enhanced in the southern Indian Ocean has been spun up to seasonal equilibrium and then driven by NCEP–NCAR reanalysis 1 monthly mean forcings and Hadley SSTs over the period 1948–2002. The aim was to simulate changes in the subsurface properties observed in hydrographic surveys at 32°S in the Indian Ocean in 1965, 1987, and 2002. These surveys showed a zonally averaged cooling on isopycnals of 0.5° and 0.3°C in mode and intermediate waters between 1965 and 1987 and a warming of the mode water coupled with a continued cooling of the intermediate water between 1987 and 2002. The major changes in isopycnal depth and temperature modeled in this study were confined to the mode water and were qualitatively similar to those observed but concentrated in a lower density class and in the eastern half of the section. The dominant changes here were multidecadal, with maximum temperatures on the σθ = 26.7 kg m−3 isopycnal being reached in 1968 and minimum temperatures in 1990. The simulations showed a propagation of interannual anomalies toward the section from a region of deep late winter mixed layers in the southeast Indian Ocean within a period of several years. Surface temperatures in this region were lowest in the 1960s and highest in the late 1980s. Temperatures on isopycnals showed the opposite variation, consistent with SST having the controlling effect on mixed layer density and depth. Isopycnal depths within the mode water were strongly correlated with temperature, implying a redistribution of mode water density classes, the greatest volume of mode water being produced in a higher density class (σθ = 26.8–27.0 kg m–3) during the period of cooler surface forcing in the 1960s and 1970s than during the warmer period following (σθ = 26.6–26.8 kg m–3).
Functional characterization of two melanocortin (MC) receptors in lamprey showing orthology to the MC1 and MC4 receptor subtypes
Authors: Haitina Tatjana , Klovins Janis , Takahashi Akiyoshi , Löwgren Maja , Ringholm Aneta , Enberg Johan , Kawauchi Hiroshi , Larson Earl T , Fredriksson Robert , Schiöth Helgi B
Published: June 2007

Background

The melanocortin (MC) receptors have a key role in regulating body weight and pigmentation. They belong to the rhodopsin family of G protein-coupled receptors (GPCRs). The purpose of this study was to identify ancestral MC receptors in agnathan, river lamprey.

Results

We report cloning of two MC receptors from river lamprey. The lamprey receptors, designated MCa and MCb, showed orthology to the MC1 and MC4 receptor subtypes, respectively. The molecular clock analysis suggested that lamprey MC receptor genes were not duplicated recently and diverged from each other more than 400 MYR ago. Expression and pharmacological characterization showed that the lamprey MCa receptor was able to bind and be activated by both lamprey and human MSH peptides. The lamprey MCa receptor had relatively high affinity for ACTH derived peptides similarly to the fish MC receptors. We found that both of the lamprey MC receptors were expressed in skin, while the MCb receptor was also found in liver, heart and skeletal muscle.

Conclusion

This study shows presence of MC receptors in agnathans indicating early signs of specific functions of melanocortin receptor subtypes.
A preliminary assessment of genetic relationships among agronomically important cultivars of black pepper
Authors: Joy Nisha , Abraham Z , Soniya EV
Published: June 2007

Background

The impact of diseases such as Phytophthora foot rot and the replacement of unproductive cultivars by high yielding ones has brought about the disappearance of varieties in Piper species, like any other crop. Black pepper (King of spices), is a major spice crop consumed throughout the world. It is widely cultivated across various parts of the world apart from India. The different cultivars may be genetically related and could be a source of valuable genes for disease resistance and an increase in quantity and quality. Even though Western Ghats in India is believed to be the site of origin of this crop, numerous accessions from the NBPGR have not yet been evaluated. Our study aims to investigate the genetic relatedness in major cultivars of black pepper using Amplified Fragment Length Polymorphism.

Results

Amplified Fragment Length Polymorphic (AFLP) DNA analysis was performed in thirty popular cultivars of black pepper from National Bureau of Plant Genetic Resources (NBPGR), India. Fingerprint profiles were generated initially with, five different primer combinations, from which three primer pair combinations (EAGC/MCAA, EAGG/MCTA and EAGC/MCTG) gave consistent and scorable banding patterns. From 173 scorable markers, 158(> 90%) were polymorphic which shows there is considerable variation in the available germplasm. The dendrogram derived by unweighted pair group method analysis (UPGMA) grouped the accessions into three major clusters and four diverse cultivars with only 30% similarity. Karimunda, a widely grown and popular cultivar was unique in the fingerprint profiles obtained.

Conclusion

There are currently few fingerprinting studies using the valuable spice crop black pepper. We found considerable genetic variability among cultivars of black pepper. Fingerprinting analysis with AFLP proved to be an ideal tool for cultivar identification and phylogenetic studies. It shows the high level of polymorphism and the unique characterization of the major cultivars. An extensive range of similarity value between the cultivars was noted (6.01 to 98.13). Further screening of more cultivars will provide valuable information for current breeding programmes.
Low-density cells isolated from the rat thymus resemble branched cortical macrophages and have a reduced capability of rescuing double-positive thymocytes from apoptosis in the BB-DP rat
Authors: Sommandas Vinod , Rutledge Elizabeth A , Van Yserloo Brian , Fuller Jessica , Lernmark Åke , Drexhage Hemmo A
Published: June 2007

Biobreeding-diabetes prone (BB-DP) rats spontaneously develop organ-specific autoimmunity and are severely lymphopenic and particularly deficient in ART2+ regulatory T cells. A special breed, the so-called BB-diabetic-resistant (DR) rats, are not lymphopenic and do not develop organ-specific autoimmunity. The genetic difference between both strains is the lymphopenia (lyp) gene. Intrathymic tolerance mechanisms are important to prevent autoimmunity, and next to thymus epithelial cells, thymus APC play a prominent part in this tolerance. We here embarked on a study to detect defects in thymus APC of the BB-DP rat and isolated thymus APC using a protocol based on the low-density and nonadherent character of the cells. We used BB-DP, BB-DR, wild-type F344, and F344 rats congenic for the lyp gene-containing region. The isolated thymus, nonadherent, low-density cells appeared to be predominantly ED2+ branched cortical macrophages and not OX62+ thymus medullary and cortico-medullary dendritic cells. Functionally, these ED2+ macrophages were excellent stimulators of T cell proliferation, but it is more important that they rescued double-positive thymocytes from apoptosis. The isolated thymus ED2+ macrophages of the BB-DP and the F344.lyp/lyp rat exhibited a reduced T cell stimulatory capacity as compared with such cells of nonlymphopenic rats. They had a strongly diminished capability of rescuing thymocytes from apoptosis (also of ART2+ T cells) and showed a reduced Ian5 expression (as lyp/lyp thymocytes do). Our experiments strongly suggest that branched cortical macrophages play a role in positive selection of T cells in the thymus and point to defects in these cells in BB-DP rats.
Next year in Jerusalem: psychotherapy training for tomorrow's consultants
Authors: Mitchison Sally
Published: June 2007

The Royal College of Psychiatrists' requirements for psychotherapy training and the role of the local psychotherapy tutor are summarised. Practical issues concerning the provision of this training are discussed, taking into account the anxieties that trainees experience. Suggestions are made about conducting case discussion groups, providing case supervision in small groups, locating short cases and arranging group and systemic therapy experience.
Herbal remedies for depression and anxiety
Authors: Ernst Edzard
Published: June 2007

Herbal remedies are used by many people suffering from anxiety or depression. It is therefore important to know whether they generate more good than harm. A systematic review of the published literature revealed trial data for Ginkgo biloba, Lavandula angustifolia, Hypericum perforatum, Valeriana officinalis, Crataegus oxyacantha, Eschscholzia californica, Matricaria recutita, Melissa officinalis, Passiflora incarnate and Piper methysticum. Only two of these herbal remedies are supported by sound evidence: Hypericum perforatum (St John's wort) for mild to moderate depression and Piper methysticum (kava) for anxiety. Neither is free of risks. Our knowledge of herbal remedies is incomplete and the subject merits rigorous study.
Take your partners please
Authors: Yeomans David
Published: June 2007

Partnership working with the voluntary sector is developing across mental health services. Such partnerships have the support of the Royal College of Psychiatrists and the Department of Health. Setting up a partnership requires enthusiastic psychiatrists who are willing to work in new ways. These psychiatrists will face issues of personal and clinical responsibility, confidentiality and fairness. They will also have to deal with continuing changes that could unsettle a new and developing collaboration. Early intervention services may use partnerships more than other adult psychiatry services, but partnerships could be established in any specialty. Psychiatrists should make sure that appropriate evaluation is built into any new partnership.
A new era in psychiatric training and assessment
Authors: Bhugra Dinesh
Published: June 2007

The Royal College of Psychiatrists is well on the way to introducing its new curriculum and revised Membership (MRCPsych) examinations and assessments, in line with the requirements of the Postgraduate Medical Education and Training Board. The new structures might encourage trainees to ask themselves how and why they are studying and learning. Organisers of local MRCPsych courses will need to tailor their courses to fit these new structures, and this might be an optimum time for the College to consider whether it should take a more formal role in approving courses and judging trainees' participation in them.
The Depression Scale as a screening instrument for a subsequent depressive episode in primary healthcare patients
Authors: Poutanen Outi , Koivisto Anna-Maija , Joukamaa Matti , Mattila Aino , Salokangas Raimo K. R.
Published: June 2007

Background

There are numerous instruments for screening for depression. A feasible screen is good at both recognising and predicting depression.

Aims

To study the ability of the Depression Scale and its items to recognise and predict a depressive episode.

Method

A sample of patients attending primary care was examined in 1991–1992 and again 7 years later. The accuracy of the Depression Scale at baseline and at follow-up was tested against the Short Form of the Composite International Diagnostic Interview (CIDI-SF) diagnosis of depression at follow-up. The sensitivity and specificity of the Depression Scale and its items were assessed.

Results

Both baseline and follow-up Depression Scale scores were consistent with the CIDI–SF diagnoses. It was possible to find single items efficient at both recognising and predicting depression.

Conclusions

The Depression Scale is a useful screening instrument for depression, with both diagnostic and predictive validity.
Impact of sexual violence on disclosure during Home Office interviews
Authors: Bögner Diana , Herlihy Jane , Brewin Chris R.
Published: June 2007

Background

Late disclosure or nondisclosure during Home Office interviews is commonly cited as a reason to doubt an asylum seeker's credibility, but disclosure may be affected by other factors.

Aims

To determine whether and how sexual violence affects asylum seekers' disclosure of personal information during Home Office interviews.

Method

Twenty-seven refugees and asylum seekers were interviewed using semi-structured interviews and self-report measures.

Results

The majority of participants reported difficulties in disclosing. Those with a history of sexual violence reported more difficulties in disclosing personal information during Home Office interviews, were more likely to dissociate during these interviews and scored significantly higher on measures of posttraumatic stress symptoms and shame than those with a history of non-sexual violence.

Conclusions

The results indicate the importance of shame, dissociation and psychopathology in disclosure and support the need for immigration procedures sensitive to these issues. Judgments that late disclosure is indicative of a fabricated asylum claim must take into account the possibility of factors related to sexual violence and the circumstances of the interview process itself.
Use of statistics in the Psychiatric Bulletin: author guidelines
Authors: Haque M. Sayeed , George Sanju
Published: June 2007

Inappropriate use of statistics can seriously undermine the validity of published medical research. This paper aims to make recommendations to authors on the use and presentation of statistics in submissions to the Psychiatric Bulletin. We derive our recommendations from a review of the quality of statistical reporting in 50 consecutive ‘original’ papers published in the Psychiatric Bulletin. However simple the methodology of a study, adequate emphasis needs to be given to the correct and appropriate use and presentation of statistics in scientific papers.
Letters to the College: past experience and practice
Authors: Seager Philip
Published: June 2007

There was no advertisement, or job interview, but somehow I found myself reading and answering the letters of comment and complaint addressed to the College. I took over from Kurt Schapira who had been similarly invited some years earlier. In this article I sum up 10 years of experience, largely derived from the days before the Patients and Carers Committee and also before emails became commonplace.
Letters to the College: current practice
Authors: Hart Deborah
Published: June 2007

How we answer patient, carer and public concerns and complaints is very important, and suitable response mechanisms need to be in place. The College continues to receive letters from patients and carers, although far fewer than in the past. These are currently dealt with by the Deputy Registrar Dr Afzal Javed, with a number of standard letters signposting people to further help and information. We also explain that the College cannot help people individually. The more contentious and distressing letters are dealt with by the Registrar Professor Sue Bailey.
Meeting NICE self-harm standards in an accident and emergency department
Authors: Hughes Leah , Kosky Nick
Published: June 2007

Aims and Method

An audit in a general hospital accident and emergency (A&E) department and the subsequent development of a triage process for people presenting with self-harm is described. A random sample of 103 people attending with self-harm were selected and their treatment audited against standards derived from NICE guidelines.

Results

The service provided by the A&E department was sub-standard. Of particular concern was the lack of processes addressing risk assessment and safe discharge. A pro forma was designed with the aim of improving assessment of self-harm. A repeat audit 3 months after introduction of the pro forma showed an improvement in the recording of relevant information underpinning risk assessment.

Clinical Implications

Procedures for those presenting to A&E departments with self-harm may not meet recommended guidelines. The use of a pro forma with staff training can improve risk assessment.