bluuebunny/crossref_metadata_2025 huggingface dataset:
Lesions of an Avian Basal Ganglia Circuit Prevent Context-Dependent Changes to Song Variability
Authors: Kao Mimi H. , Brainard Michael S.
Published: May 2006

Trial-by-trial variability is important in feedback-based motor learning. Variation in motor output enables evaluation mechanisms to differentially reinforce patterns of motor activity that produce desired behaviors. Here, we studied neural substrates of variability in the performance of adult birdsong, a complex, learned motor skill used for courtship. Song performance is more variable when male birds sing alone (undirected) than when they sing to females (directed). We test the role of the anterior forebrain pathway (AFP), an avian basal ganglia–forebrain circuit, in this socially driven modulation of song variability. We show that lesions of the lateral magnocellular nucleus of the anterior nidopallium (LMAN), the output nucleus of the AFP, cause a reduction in the moment-by-moment variability in syllable structure during undirected song to the level present during directed song. This elimination of song modulation is immediate and long-lasting. We further show that the degree of syllable variability and its modulation are both attenuated in older birds, in concert with decreased variability of LMAN activity in these birds. In contrast to the requirement of LMAN for social modulation of syllable structure, we find that LMAN is not required for modulation of other features of song, such as the number of introductory elements and motif repetitions and the ordering of syllables or for other motor and motivational aspects of courtship. Our findings suggest that a key function of avian basal ganglia circuitry is to regulate vocal performance and plasticity by specifically modulating moment-by-moment variability in the structure of individual song elements.
Uncertainty and Invariance in the Human Visual Cortex
Authors: Tjan Bosco S. , Lestou Vaia , Kourtzi Zoe
Published: May 2006

The way in which input noise perturbs the behavior of a system depends on the internal processing structure of the system. In visual psychophysics, there is a long tradition of using external noise methods (i.e., adding noise to visual stimuli) as tools for system identification. Here, we demonstrate that external noise affects processing of visual scenes at different cortical areas along the human ventral visual pathway, from retinotopic regions to higher occipitotemporal areas implicated in visual shape processing. We found that when the contrast of the stimulus was held constant, the further away from the retinal input a cortical area was the more its activity, as measured with functional magnetic resonance imaging (fMRI), depended on the signal-to-noise ratio (SNR) of the visual stimulus. A similar pattern of results was observed when trials with correct and incorrect responses were analyzed separately. We interpret these findings by extending signal detection theory to fMRI data analysis. This approach reveals the sequential ordering of decision stages in the cortex by exploiting the relation between fMRI response and stimulus SNR. In particular, our findings provide novel evidence that occipitotemporal areas in the ventral visual pathway form a cascade of decision stages with increasing degree of signal uncertainty and feature invariance.
Comparison of Effector-Specific Signals in Frontal and Parietal Cortices
Authors: Lawrence Bonnie M. , Snyder Lawrence H.
Published: May 2006

We previously demonstrated that the activities of neurons in the lateral intraparietal area (LIP) and the parietal reach region (PRR) of the posterior parietal cortex (PPC) are modulated by nonspatial effector-specific information. We now report similar modulation in FEF, an area of frontal cortex that is reciprocally connected with LIP. Although it is possible that these effector-specific signals originate in LIP and are conveyed to FEF, it is also possible that these signals originate in FEF and are “fed back” to LIP. We found that signal magnitude was no larger, and onset time no earlier, in FEF compared with LIP. Moreover, effector-specific activity in FEF, but not in LIP, was largely driven by spatial prediction. These results suggest that the saccade-related effector-specific signals found in LIP do not originate in FEF. Conversely, LIP may contribute to the effector-specific signals found in FEF, but does not wholly account for them.
Cognitive-Developmental and Behavior-Analytic Theories: Evolving into Complementarity
Authors: Overton Willis F. , Ennis Michelle D.
Published: May 2006

Historically, cognitive-developmental and behavior-analytic approaches to the study of human behavior change and development have been presented as incompatible alternative theoretical and methodological perspectives. This presumed incompatibility has been understood as arising from divergent sets of metatheoretical assumptions that take the form of ontological and epistemological principles, and constitute worldviews. Classically, cognitive-developmental approaches have been cast as deriving from an organismic worldview and behavior-analytic approaches from a contextualist worldview. Previous attempts at uniting the two approaches have entailed privileging one and radically modifying the other. The present paper argues that a meaningful integration requires a set of metatheoretical assumptions that transcends both worldviews, and, while maintaining their distinct qualities, unites them. This metatheoretical framework termed relational metatheory is described and its integrative implications explained.
The Application of DIGE-Based Proteomics to Renal Physiology
Authors: Hoorn Ewout J. , Hoffert Jason D. , Knepper Mark A.
Published: May 2006

Proteomics is seeing increasing use as a means of identifying new mechanistic hypotheses in physiology. Proteomics based on two-dimensional electrophoresis (2-DE) has recently been optimized with the development of Difference Gel Electrophoresis (DIGE). In DIGE-based proteomics, the experimental and control samples are derivatized with different fluorophores and are run in the same gel, thereby minimizing technical variation. DIGE is currently one of the few techniques to perform quantitative proteomics, generating a statistical output to differences in protein abundances. In this review, we discuss the principles of DIGE-based proteomics, including sample preparation, 2-DE, statistical analysis of 2D-gels, and mass spectrometry. Strengths and weaknesses of DIGE are discussed, including possible solutions to overcome certain limitations, such as the identification of low abundance and integral membrane proteins. In addition, we provide a brief synopsis of our recent experiments in which DIGE-based proteomics was applied to study vasopressin signaling in the renal collecting duct. Finally, we illustrate how quantification based on the DIGE approach combined with bioinformatics may facilitate the study of systems biology of the kidney.
Estimating Haplotype Effects on Dichotomous Outcome for Unphased Genotype Data Using a Weighted Penalized Log-Likelihood Approach
Authors: Souverein Olga W. , Zwinderman Aeilko H. , Tanck Michael W.T.
Published: May 2006

Objective: To develop a method to estimate haplotype effects on dichotomous outcomes when phase is unknown, that can also estimate reliable effects of rare haplotypes. Methods: In short, the method uses a logistic regression approach, with weights attached to all possible haplotype combinations of an individual. An EM-algorithm was used: in the E-step the weights are estimated, and the M-step consists of maximizing the joint log-likelihood. When rare haplotypes were present, a penalty function was introduced. We compared four different penalties. To investigate statistical properties of our method, we performed a simulation study for different scenarios. The evaluation criteria are the mean bias of the parameter estimates, the root of the mean squared error, the coverage probability, power, Type I error rate and the false discovery rate. Results: For the unpenalized approach, mean bias was small, coverage probabilities were approximately 95%, power ranged from 15.2 to 44.7% depending on haplotype frequency, and Type I error rate was around 5%. All penalty functions reduced the standard errors of the rare haplotypes, but introduced bias. This trade-off decreased power. Conclusion: The unpenalized weighted log-likelihood approach performs well. A penalty function can help to estimate an effect for rare haplotypes.
Predicting Anastomotic Disruption after Emergent Small Bowel Surgery
Authors: Nair Amit , Pai Dinker R. , Jagdish S.
Published: May 2006

Background/Aims: Small bowel anastomoses performed in the emergent setting have a high risk of leakage. Attention to technical detail is imperative but does not guarantee success in these situations. We sought out factors that could play a role in the process of anastomotic dehiscence under these conditions. Methods: 70 patients underwent 74 emergency small bowel anastomoses over a 21-month period in our institution during this prospective study. Patients with anastomotic disruption formed the case group and those without, the control group. Several preoperative, intraoperative and postoperative variables identified at the outset of the study were analyzed for possible associations with anastomotic dehiscence. Results: Suture line disruption occurred in 26 of 74 anastomoses (35%). The duration of symptoms before presentation did not differ significantly between groups. Hypoalbuminemia (p = 0.004), hyponatremia at presentation (p = 0.012), and intraoperative hypotension (p = 0.042) were found to be significantly associated with disruption. Neither the nature of the primary pathology in the bowel nor the anastomotic level had a significant bearing on anastomotic leakage. Conclusion: Risk factors for leakage of emergent small bowel anastomoses include hypoalbuminemia, hyponatremia at presentation, and intraoperative hypotension. Under these circumstances, the creation of a temporary stoma or exteriorization may be a wiser option than primary anastomosis.
Treatment of Rectal Cancer: Reduction of Local Recurrence after the Introduction of TME – Experience from One University Hospital
Authors: Bernardshaw Soosaipillai V. , Øvrebø Kjell , Eide Geir E. , Skarstein Arne , Røkke Ola
Published: May 2006

Background: Local recurrence (LR) of cancer after rectal surgery is followed by significant morbidity and mortality. Since the introduction of total mesorectal excision (TME) the rates of LR have decreased in many centres. The aim of this retrospective study was to investigate the effect of TME on the recurrence rates of rectal cancer and the impact of the surgeons. Methods: All patients resected for invasive rectal cancer from 1990 until 2000 were initially included in the study. From February 1994, TME was adopted as the standard treatment (TME group). Before this period, rectal surgery was performed by the non-TME technique (non-TME group). To obtain homogeneity, patients who underwent preoperative irradiation, emergency operations, pre- or intraoperative bowel perforation, residual tumour stage (R1,2) including Dukes’ D stage and postoperative mortality within 31 days, were excluded. 139 patients in the non-TME group and 181 patients in the TME group were found eligible for analyses. Results: The estimated LR rate at 1, 3 and 5 years was 7, 15 and 17% (non-TME) versus 4, 9 and 9% (TME) (p = 0.046, log-rank test). The anastomotic leakage rate was 6% (non-TME) versus 4% (TME) (not significant). Perioperative blood loss >500 ml, reoperations during the hospital stay and lymph node (N) stage were the independent risk factors for LR in the multivariate analysis. The case volume did not significantly influence LR rates. However, the variability of individual surgical results was reduced after the introduction of TME. Conclusions: TME yields significantly lower LR rates compared with traditional surgery. Since the introduction of TME, experience with rectal surgery has been gathered by a limited number of surgeons. The results of individual surgeons have consistently improved and the variability of individual surgical results is now at a lower level.
Postoperative Joint Symptoms: A Risk Factor for Pouchitis in Ulcerative Colitis Patients
Authors: Nakamura Mitsuhiro , Ikeuchi Hiroki , Nakano Hiroki , Uchino Motoi , Noda Masafumi , Yanagi Hidenori , Yamamura Takehira
Published: May 2006

Background: The prevalence and significance of joint symptoms appearing in patients with ulcerative colitis (UC) following a colectomy are unclear. Aim: We investigated the relationship between joint symptoms during steroid tapering following an ileal pouch-anal anastomosis (IPAA) and the cumulative risk for developing pouchitis. Patients and Methods: The medical records of 571 patients who underwent an IPAA with a mucosectomy were retrospectively reviewed to evaluate their joint symptoms. A diagnosis of pouchitis was obtained using the Pouchitis Disease Activity Index (PDAI) and the cumulative risk of pouchitis was estimated using a Kaplan-Meier life table analysis. Results: Joint symptoms during steroid tapering were reported by 126 (22.0%) of the UC patients and each of those had involvement of the small joints of the hand. The main symptoms were pain and stiffness, especially in the morning. The cumulative risk for developing pouchitis after 10 years was found to be 20% in patients who experienced joint symptoms during steroid tapering and 10% in those without those symptoms (p = 0.001). Conclusion: The presence of joint symptoms during steroid tapering is a significant risk factor for the development of pouchitis in patients who have undergone an IPAA for UC.
Long-Term Graft Outcome of Pediatric Liver Transplantation in Copenhagen: Analysis of the First 51 Cases
Authors: Yamauchi Yasushi , Yamashita Yuichi , Wettergren Andre , Larsen Peter N. , Rasmussen Allan , Mikami Koji , Shirakusa Takayuki , Kirkegaard Preben
Published: May 2006

Background: Graft loss after liver transplantation remains a significant problem, especially in pediatric patients. The aim of this study was to assess our initial series of pediatric liver transplantation and to identify the risk factors that influence graft outcome. Methods: The first 51 transplantations were analyzed retrospectively. All transplantations were stratified into three groups according to graft type (full-size, reduced-size, and living-related-donor graft). Survival data of the grafts were stratified and multivariate analysis conducted with respect to preoperative and surgical factors. Results: Seventeen of all the transplants were full-size grafts and 34 technical-variant grafts (27 reduced-size grafts from cadavers and 7 living-related-donor grafts). The overall graft survival rates were 65, 62 and 53% at 1, 3 and 5 years, respectively. Twenty-three of 51 grafts (45%) were lost. Poor status of the recipients (hospitalization or intensive care unit care before surgery), a retransplanted graft, and a reduced-size graft were independent risk factors for graft failure. With experience, overall graft survival has improved significantly and the differences in graft survival between graft types have disappeared. Conclusions: To improve graft survival after pediatric liver transplantation, the timely referral of potential recipients to the transplant team and employing a meticulous technique during the operation, particularly for the technical-variant graft, are required.
Epidermal Growth Factor Receptor Expression in Pancreatic Carcinoma Using Tissue Microarray Technique
Authors: Bloomston Mark , Bhardwaj Atul , Ellison E. Christopher , Frankel Wendy L.
Published: May 2006

Background: The effect of overexpression of epidermal growth factor receptor (EGFR) in pancreatic carcinoma is not clear. Utilizing tissue microarrays, we evaluated EGFR expression in pancreatic cancer to determine the association of EGFR expression with histopathologic characteristics and patient outcome. Methods: 71 cases of pancreatic adenocarcinoma and 18 cases of chronic pancreatitis were retrieved from archival files. Tissue cores from donor blocks were arrayed to create a tissue microarray. Sections were stained with EGFR and the intensity of membranous staining and percentage of tumor cells showing immunoreactivity were determined. At least 1% membranous staining and 1+ intensity were considered positive. Results: EGFR was present in 49 of 71 (69%) cases of pancreatic adenocarcinoma and 7 of 18 (39%) cases of chronic pancreatitis (p = 0.03). There was no statistically significant correlation between intensity or extent of EGFR expression and tumor grade, size, or lymph node status. While median survival was nearly twice as long when EGFR was expressed (15.2 vs. 8.3 months), this did not reach statistical significance. Conclusions: EGFR is overexpressed in pancreatic cancers independent of histopathologic characteristics and does not predict survival. Immunohistochemical analysis of EGFR staining may help in identifying candidates for EGFR inhibitor therapy.
Role of Node Dissection for Lymphatic Remetastasis in Repeat Hepatectomy for Colorectal Liver Metastasis
Authors: Sakaguchi Takanori , Suzuki Shohachi , Nakamura Satoshi , Konno Hiroyuki
Published: May 2006

Background: Although the prognosis after hepatectomy for colorectal liver metastasis with hilar node remetastasis is poor, the role of node dissection for lymphatic remetastasis at repeat hepatectomy for hepatic recurrence is unknown. Methods: Fifty patients who underwent node dissection plus hepatectomy were retrospectively reviewed and divided into three groups: group I, 38 patients with a negative node; group II, 6 with a positive node at initial hepatectomy, and group III, 6 with a positive node at repeat hepatectomy. Results: The 5-year survival rate after initial hepatectomy in group I was 46%. All patients in group II died within 2 years after surgery. In group III, the median survival time was 42 months after repeat hepatectomy, and 4 patients survived for more than 5 years after initial hepatectomy. Disease-free time was more than 1 year after initial hepatectomy in all long-term survivors. In addition, node metastasis was limited around the hepatic pedicle and postpancreatic area in 3 of 4 long-term survivors. Conclusions: Node dissection for lymphatic remetastasis may contribute to longer survival only when node metastasis is limited around the hepatic pedicle and postpancreatic area at repeat hepatectomy performed more than 1 year after the initial hepatectomy.
Full and Partial Post-Traumatic Stress Disorder among World War II Prisoners of War
Authors: Favaro Angela , Tenconi Elena , Colombo Giovanni , Santonastaso Paolo
Published: May 2006

Background: The aim of the study is to evaluate the frequency and characteristics of full and partial post-traumatic stress disorder (PTSD) among 66 World War II Nazi prisoners of war, some of whom had been deported to death camps. Methods: The Structured Clinical Interview for DSM-IV was used to assess the presence of PTSD and major depression. The Dissociative Experiences Scale and the 58-item version of the Hopkins Symptom Checklist were also administered. Partial PTSD was defined as the presence of at least one symptom in each of the clusters defined by DSM-IV. Results: Forty-eight percent of the subjects have a partial PTSD, while 20% reported the full syndrome. When compared to subjects with full PTSD, those with partial PTSD showed a significantly lower frequency of comorbid depression and lower levels of psychological distress, as measured by the Symptom Checklist. No differences were found with regards to dissociative symptoms and help-seeking. Conclusions: The problem of definition of PTSD partial syndromes deserves more attention in the literature.
Auditory Recognition Memory, Conscious Recollection, and Executive Function in Patients with Schizophrenia
Authors: Drakeford Justine L. , Edelstyn Nicola M. , Oyebode Femi , Srivastava Shrikant , Calthorpe William R. , Mukherjee Tirthankar
Published: May 2006

Background: Dual-process models propose that recognition memory (RM) involves two processes: conscious recollection and familiarity-aware memory. Studies investigating RM in schizophrenia report a selective deficit in conscious recollection and intact levels of familiarity-driven RM for stimuli presented in the visual and olfactory domains. It has been suggested that abnormalities in conscious recollection result from a breakdown in frontal strategic memory processes involved in encoding and retrieval and executive functions linked to reality monitoring and decision making. We investigated three predictions arising from these proposals. Firstly, if conscious recollection abnormalities arise from a central impairment, then these abnormalities should not be domain specific. Secondly, if the deficits in conscious recollection arise from a breakdown in executive processes, deficiencies should be correlated with executive dysfunction. Finally, the conscious recollection deficiencies are likely to be more severe in schizophrenia, a condition associated with marked executive dysfunction relative to Major Depressive Disorder, Recurrent (MDDR), in which executive dysfunction is less marked. Methods: The remember/know paradigm was used to investigate RM for voices in three groups: patients with schizophrenia (n = 14), patients with MDDR (n = 16), and normal controls (n = 16). Executive function was assessed using the Wisconsin Card Sorting Task. Results: Patients with schizophrenia made significantly fewer remember responses than normal controls (p < 0.01), despite normal levels of discrimination and familiarity-driven auditory RM. Patients with MDDR did not differ significantly from either normal controls or patients with schizophrenia. Executive dysfunction was limited to the schizophrenia group and was not correlated with conscious recollection deficiencies. Conclusions: Patients with schizophrenia exhibit a deficit in conscious recollection for auditory RM of voices. These findings, when considered alongside remember/know data collected from the same set of patients for olfactory and visual RM, support proposals that abnormalities in conscious recollection stem from a breakdown in central rather than domain-specific processes.
Phenotypic Characterization of DFNA24: Prelingual Progressive Sensorineural Hearing Impairment
Authors: Santos Regie Lyn P. , Häfner Franziska M. , Huygen Patrick L.M. , Linder Thomas E. , Schinzel Albert A. , Spillmann Thomas , Leal Suzanne M.
Published: May 2006

This article describes the hearing impairment (HI) phenotype which segregates in a large multi-generation Swiss-German family with autosomal dominant nonsyndromic HI. The locus segregating within this pedigree is located on chromosome 4q35-qter and is designated as DFNA24. For this pedigree, audiometric data on 25 hearing-impaired family members are available. It was demonstrated that within this kindred the HI is sensorineural, bilateral, prelingual in onset, and progressive throughout life. Age-related typical audiograms depict steeply down-sloping curves, with moderate high-frequency HI at birth, then steady progression to moderate HI in the low frequencies, severe HI at mid-frequencies and profound HI at high frequencies by age 70. Annual threshold deterioration was ∼0.5 dB/year at 1–2 kHz after correction for presbycusis.
A Modified Version of Tinnitus Retraining Therapy: Observing Long-Term Outcome and Predictors
Authors: Mazurek Birgit , Fischer Franziska , Haupt Heidemarie , Georgiewa Petra , Reisshauer Anette , Klapp Burghard F.
Published: May 2006

Tinnitusretraining therapy (TRT) in Germany includes not only directive counseling and sound therapy but also stress management and facultative psychotherapeutic treatment. The aim of the present study was to investigate the impact of this modified version of TRT on certain tinnitus-related aspects of distress and variables that may predict treatment outcome. Clinical data from 92 patients undergoing outpatient TRT in the Charité Tinnitus Centre were evaluated retrospectively over 1 year. Treatment outcome was defined by changes in specific areas of tinnitus-related distress and assessed by the Tinnitus Questionnaire. Changes in audiometric frequency and loudness of tinnitus were examined by regular audiometric testing. The overall Tinnitus Questionnaire score was significantly reduced after 1 year. Severely affected tinnitus sufferers (decompensated tinnitus) profited more than less affected patients (compensated tinnitus). In cases of indicated psychotherapy, improvement was significant for the patients who took advantage of psychotherapeutic treatment during TRT but was not significant for those who interrupted or dismissed an indicated psychotherapy. Changes in tinnitus-specific areas of distress were most pronounced in the scales for emotional and cognitive distress and intrusiveness. Significant changes in sleep disturbances, auditory perceptual difficulties and somatic complaints were observed in patients with decompensated tinnitus. In patients with chronic tinnitus, modified TRT may lead to significant subjective improvement in certain tinnitus-related symptoms like emotional and cognitive distress and intrusiveness. Particularly patients suffering from severe tinnitus distress take advantage of therapy. Careful psychotherapeutic diagnostics and therapies and, if necessary, motivation to make use of psychotherapy seem to be essential preconditions for therapeutic success in patients with severe psychosomatic comorbidity.
Aortic Stiffness, Flow-Mediated Dilatation and Carotid Intima-Media Thickness in Obstructive Sleep Apnea
Authors: Tanriverdi Halil , Evrengul Harun , Kara Cuneyt Orhan , Kuru Omur , Tanriverdi Seyhan , Ozkurt Sibel , Kaftan Asuman , Kilic Mustafa
Published: May 2006

Background and Objective: Obstructive sleep apnea (OSA) has a critical association with cardiovascular mortality and morbidity. Carotid intima-media thickness (IMT), flow-mediated dilatation (FMD) and aortic stiffness are early signs of atherosclerosis. The presence of subclinical atherosclerosis was assessed in OSA patients using these parameters. Methods: 40 patients with OSA showing an apnea-hypopnea index (AHI) ≧5 (mean age 51.3 ± 9 years, 32 males) and 24 controls (AHI < 5, mean age 51.9 ± 5.2 years, 19 males) were enrolled in the study. In all subjects, polysomnographic examination and recordings were performed during sleep. IMT of the carotid artery, endothelium-dependent/-independent vasodilation of the brachial artery and aortic elastic parameters were investigated using high-resolution Doppler echocardiography. Results: The demographic data of the patients with OSA and controls were not significantly different. Subjects with OSA demonstrated higher values of aortic stiffness (7.1 ± 1.88 vs. 6.42 ± 1.56, respectively) and IMT (0.85 ± 0.13 vs. 0.63 ± 0.11 mm, p = 0.0001, respectively) but lower distensibility (9.47 ± 1.33 vs. 11.8 ± 3.36 cm2/dyn/106) and FMD (4.57 ± 1.3 vs. 6.34 ± 0.83%, p = 0.0001, respectively) than the controls. The respiratory disturbance index correlated positively with aortic stiffness and IMT and negatively with distensibility and FMD. Conclusion: We observed blunted endothelium-dependent dilatation, increased carotid IMT and aortic stiffness in patients with OSA compared with matched control subjects. This is evident in the absence of other diseases, suggesting that OSA is an independent cause of atherosclerosis. These simple and non-invasive methods help to detect subclinical atherosclerosis in OSA.
Lack of Long-Term Protective Effect of Antioxidant/Anti-Inflammatory Therapy in Transplant-Induced Ischemia/Reperfusion Injury
Authors: Tain You-Lin , Muller Veronika , Szabo Attila , Dikalova Anna , Griendling Kathy , Baylis Chris
Published: May 2006

Background: Alloantigen-independent factors contribute to long-term damage in renal transplant recipients, likely due to ischemia/reperfusion (I/R) injury at transplantation (Tx). I/R injury promotes oxidative stress and inflammation resulting in endothelial injury. Methods: In this study we investigated the long-term efficacy (22 weeks) of short-term (10 day) endothelial protection therapy (EP) in ‘optimal’ donor kidneys using the male Fisher 344 rat isograft (ISO) model. ISO-EP kidneys were compared to untreated ISO (ISO-UN) kidneys. EP involved dexamethasone to donor, ex vivo treatment of the kidney with deferoxamine and tempol, and administration to the recipient of L-arginine and tempol for 10 days. Rats were sacrificed 22 weeks following Tx and compared to age-matched, normal controls. Results: Both groups of ISO Tx rats developed similar renal dysfunction and structural damage and renal NADPH-oxidase-dependent O2– production was similarly elevated in ISO-UN and ISO-EP groups vs. controls. In vitro renal cortex NO synthase (NOS) activity was also similar in ISO-UN and ISO-EP rats, despite lower nNOS and eNOS protein abundance in ISO-EP. Conclusion: I/R injury-induced late graft dysfunction occurs even when optimal donors are used and when short-term EP treatment is given. Increased renal superoxide production is not prevented by short-term EP therapy.
From Pulsus to Pulseless
Authors: Weiss James N. , Karma Alain , Shiferaw Yohannes , Chen Peng-Sheng , Garfinkel Alan , Qu Zhilin
Published: May 2006

Computer simulations and nonlinear dynamics have provided invaluable tools for illuminating the underlying mechanisms of cardiac arrhythmias. Here, we review how this approach has led to major insights into the mechanisms of spatially discordant alternans, a key arrhythmogenic factor predisposing the heart to re-entry and lethal arrhythmias. During spatially discordant alternans, the action potential duration (APD) alternates out of phase in different regions of the heart, markedly enhancing dispersion of refractoriness so that ectopic beats have a high probability of inducing reentry. We show how, at the cellular level, instabilities in membrane voltage (ie, steep APD restitution slope) and intracellular Ca (Ca
i
) cycling dynamics cause APD and the Ca
i
transient to alternate and how the characteristics of alternans are affected by different “modes” of the bidirectional coupling between voltage and Ca
i
. We illustrate how, at the tissue level, additional factors, such as conduction velocity restitution and ectopic beats, promote spatially discordant alternans. These insights have illuminated the mechanistic basis underlying the clinical association of cardiac alternans (eg, T wave alternans) with arrhythmia risk, which may lead to novel therapeutic approaches to avert sudden cardiac death.
"Women Behaving Badly": Crime, Transgressive Behaviour and Gender In Early Twentieth Century China
Authors: Bailey Paul
Published: May 2006

This article analyses a critical discourse on women that was pervasive in an emerging newspaper and periodical press during the last years of the Qing dynasty and early years of the Republic, at a time when governing and intellectual elites were becoming increasingly obsessed with 'behavioural modernization'. This critical discourse reflected anxieties concerning the pace and direction of social and cultural change, as well as ambivalence about women's growing public visibility. At the same time, such a discourse provides an insight into how adolescent girls and women responded to new opportunities in the public sphere before the May Fourth Movement, and clearly shows they did not always behave in ways prescribed by officials, educators and intellectuals.
Globalisation's Challenge to the Islamic Ummah
Authors: Hassan Riaz
Published: May 2006

The concept of ummah embodies the universalism of Islam and provides a framework for religious unity, which accommodates the cultural diversity of believers. It is an important part of historical as well as contemporary discourse on Islam. This paper provides an overview of the development and evolution of the concept of ummah and its usage in Islamic discourse to explain the current social, political and economic conditions of the Muslim world. It reports the findings about ummah consciousness and its relationship to modernity in Muslim countries of Southeast Asia, South and Central Asia, and the Middle East. It will examine the impact of globalisation on the Islamic ummah and how it is shaping the emerging struggle between 'hybridity' and 'authenticity' among Muslims and Islamic movements. The paper will explore the challenges of this struggle and its sociological implications for the 'de-centering' of the Muslim world into multiple autonomous regions. It will argue that the future of the Muslim ummah may gain strength not as a unified and unitary community, but as a differentiated community consisting of ummahs representing different Islamic regions. Each regional ummah will possess and embody a unique character that has been moulded by the history and temperament of its people. The paper will conclude with some observations on the future religious, intellectual, economic and political trajectories of Muslim countries.
Moralising Ancestors as Socio-moral Capital: A Study of a Transnational Chinese Lineage
Authors: Khun Eng Kuah-Pearce
Published: May 2006

Within the Chinese Diaspora, ancestor worship is an important cultural element that binds a group of people together and provides them with a sense of comfort, kinship and communal identity as they sink their cultural roots in a new country, luodi shenggen. Thus, ancestor worship is widely reproduced and practised by the Chinese in the Diaspora, as it is central to the Chinese understanding of the continuation of family and lineage. However, in Mainland Chinese villages, the practice of ancestor worship, which is still considered important by the villagers, was not allowed until the Open Door Policy in 1978. With this policy, emigrant villages, (qiaoxiang) embarked on an aggressive campaign to woo the Chinese in overseas communities to return to their native villages to help with economic development through various strategies. One of the strategies is to allow for the revival and practice of ancestor worship in the rural villages. This paper explores how ancestors continued to be regarded as important members of a transnational lineage in the Fujian Province in South China, and also in Singapore. Because of the central focus on ancestors and ancestor worship in the Chinese society, ancestors are moralised as a significant social capital by the Chinese State, local government and rural villagers, in an attempt to establish transnational guanxi linkages between the ancestral villages in rural China and their Diaspora members in Singapore. The Chinese State, with instrumental consideration, sees this transnational guanxi networks and the revival of ancestor worship as a strategy to encourage the Chinese Diaspora to visit their ancestral home and help with village development.
Scaling Baroclinic Eddy Fluxes: Vortices and Energy Balance
Authors: Thompson Andrew F. , Young William R.
Published: May 2006

The eddy heat flux generated by the statistically equilibrated baroclinic instability of a uniform, horizontal temperature gradient is studied using a two-mode f-plane quasigeostrophic model. An overview of the dependence of the eddy diffusivity D on the bottom friction κ, the deformation radius λ, the vertical variation of the large-scale flow U, and the domain size L is provided by numerical simulations at 70 different values of the two nondimensional control parameters κλ/U and L/λ. Strong, axisymmetric, well-separated baroclinic vortices dominate both the barotropic vorticity and the temperature fields. The core radius of a single vortex is significantly larger than λ but smaller than the eddy mixing length ℓmix. On the other hand, the typical vortex separation is comparable to ℓmix. Anticyclonic vortices are hot, and cyclonic vortices are cold. The motion of a single vortex is due to barotropic advection by other distant vortices, and the eddy heat flux is due to the systematic migration of hot anticyclones northward and cold cyclones southward. These features can be explained by scaling arguments and an analysis of the statistically steady energy balance. These arguments result in a relation between D and ℓmix. Earlier scaling theories based on coupled Kolmogorovian cascades do not account for these coherent structures and are shown to be unreliable. All of the major properties of this dilute vortex gas are exponentially sensitive to the strength of the bottom drag. As the bottom drag decreases, both the vortex cores and the vortex separation become larger. Provided that ℓmix remains significantly smaller than the domain size, then local mixing length arguments are applicable, and our main empirical result is ℓmix ≈ 4λ exp(0.3U/κλ).
Heat and Freshwater Transport through the Central Labrador Sea*
Authors: Straneo F.
Published: May 2006

The seasonal and interannual variations in the export of Labrador Sea Water (LSW), and in the heat and freshwater transport through the central Labrador Sea, are examined for two different periods: from 1964 to 1974, using Ocean Weather Station Bravo data, and from 1996 to 2000, using data collected from profiling floats. A typical seasonal cycle involves a 300-m thickening of LSW (convection) followed by an equivalent thinning (restratification). Restratification is characterized by a drift of properties toward boundary current values that is indicative of a vigorous lateral exchange. The net result is a convergence of heat and salt, between 200 and 700 m, that balances the net surface heat loss to the atmosphere and partially offsets the surface freshwater accumulation due to surface, lateral exchange. Interannual variations in the export of LSW can be explained by taking into account changes in the central Labrador Sea–boundary current density gradient, which governs the lateral exchange. Interannual variations in how much heat is converged into the region, on the other hand, mostly reflect changes in the temperature of LSW. This only partly explains, however, the increased convergence of heat that occurs during the late 1990s. In years in which convection does not occur, restratification trends continue throughout the entire year, albeit at a reduced rate.
A Decomposition of the Atlantic Meridional Overturning Circulation into Physical Components Using Its Sensitivity to Vertical Diffusivity
Authors: Mignot Juliette , Levermann Anders , Griesel Alexa
Published: May 2006

The sensitivity of the Atlantic Ocean meridional overturning circulation to the vertical diffusion coefficient κ in the global coupled atmosphere–ocean–sea ice model CLIMBER-3α is investigated. An important feature of the three-dimensional ocean model is its low-diffusive tracer advection scheme. The strength Mmax of the Atlantic overturning is decomposed into three components: 1) the flow MS exported southward at 30°S, 2) the large-scale upward flow that balances vertical diffusion in the Atlantic, and 3) a wind-dependent upwelling flux Wbound along the Atlantic boundaries that is not due to vertical diffusion. The export of water at 30°S varies only weakly with κ, but is strongly correlated with the strength of the overflow over the Greenland–Scotland ridge. The location of deep convection is found to be mixing dependent such that a shift from the Nordic seas to the Irminger Sea is detected for high values of κ. The ratio R = MS/Mmax gives a measure of the interhemispheric overturning efficiency and is found to decrease linearly with κ. The diffusion-induced upwelling in the Atlantic is mostly due to the uniform background value of κ while parameterization of enhanced mixing over rough topography and in stratified areas gives only a weak contribution to the overturning strength. It increases linearly with κ. This is consistent with the classic 2/3 scaling law only when taking the linear variation of the density difference to κ into account. The value of Wbound is roughly constant with κ but depends linearly on the wind stress strength in the North Atlantic. The pycnocline depth is not sensitive to changes in κ in the model used herein, and the results suggest that it is primarily set by the forcing of the Southern Ocean winds. The scaling of the total overturning strength with κ depends on the combined sensitivity of each of the terms to κ. In the range of background diffusivity values in which no switch in deep convection sites is detected, Mmax scales linearly with the vertical diffusivity. It is argued that scalings have, in general, to be interpreted with care because of the generally very small range of κ but also because of possible shifts in important physical processes such as deep convection location.
Generation and Initial Evolution of a Mode Water θ–S Anomaly*
Authors: Johnson Gregory C.
Published: May 2006

Generation and evolution of an isopycnal potential temperature–salinity (θ–S), or spiciness, anomaly is studied around 20°–23°S, 110°W in the austral winter of 2004. Two profiling CTD floats deployed in the region in January 2004 provide the observations. The anomaly (defined as relative to water properties of the preceding summer) is very large (initially about 0.35 in S and about 0.9°C in θ). It is associated with the winter ventilation of a thick, low-potential-vorticity layer known as South Pacific Eastern Subtropical Mode Water. Regional lateral θ and S distributions at the surface predispose the ocean to formation of this water mass and allow significant anomalies to be generated there with relative ease. The water mass is potentially important for climate in that, after northwestward advection in the South Equatorial Current, it contributes to the Equatorial Undercurrent and eventually resurfaces in the cold tongue of the eastern equatorial Pacific Ocean. The anomaly studied is strong enough to predispose a portion of the water column to salt fingering, increasing vertical mixing. Although lateral processes are no doubt important in evolution of the anomaly, the vertical mixing appears to be sufficiently vigorous to reduce it significantly within 6 months after its formation by spreading it to denser horizons through diapycnal fluxes. By that time the anomaly is most likely sufficiently diffuse so that subsequent evolution from diapycnal fluxes is significantly reduced as it makes its way toward the equator.
Deep Footprints of Odyssey
Authors: Yinzeng Geng
Published: May 2006

This is the presentation of the joint project on twenty centuries of civilisational dialogue between India and China, India and China: Twenty Centuries of Civilizational Interaction and Vibrations, with Professor Tan Chung. Chinese literature, in its gigantic historical spatiality, has captured crucial glimpses and registered innumerable milestones of the odyssey of India–China civilisational dialogue. The division of labour between me and Professor Tan Chung is—while he uses a positional approach to try to juxtapose and integrate the diachronic and synchronic contexts of historical events, I follow the ‘shu er bu zuo’ (presentation without creation) motto of Confucius. The India–China civilisational dialogue took place not between government institutions, but among the ordinary people. Information about the dialogue inevitably originated from oral sources, and was later found in written reportage in a variety of genres.
Sino-Indian Cultural Synergy
Authors: Chung Tan
Published: May 2006

This is the presentation of the joint project on twenty centuries of civilisational dialogue between India and China, India and China: Twenty Centuries of Civilizational Interaction and Vibrations, with Professor Geng Yinzeng. The ‘Clash of Civilisations’ and ‘Civilisational Dialogue’ marks the major difference between the historical development of the Western and Eastern Hemispheres. In the West, Clash of Civilisations seems to have never ended since the emergence of ancient Egypt and Babylon. But, there has never been a Clash of Civilisations in the Eastern Hemisphere thanks to the dominance of India and China as well as their mutual interactions and vibrations throughout history. Ancient civilisations in the West pursue a ‘face-to-face’ relationship with each other. Under the impact of hegemony, each civilisation aspires to be ‘on top of the world’, striving to destroy its rival. In the East, India and China never underwent such a course vis-à-vis each other and pursue a ‘back-to-back’ relationship. The book is an overview of the ‘back-to-back’ India–China civilisational dialogue which distinguished itself by three elements: (1) pilgrimage, (2) translation of Buddhist scriptures from Pali and Sanskrit into Chinese, and (3) trade and diplomacy.
Sino-Pak ‘Entente Cordiale’* and India
Authors: Deepak B.R.
Published: May 2006

The rationale behind ‘Sino-Pak Entente Cordiale: A Look into the Past and Future’ is to stimulate reflection and open debate on this sensitive topic. The article analyses the three Indo-Pak wars and the India–China boundary conflict in historical and geopolitical contexts to explore whether there is a correlation between these and the formation of an entente between China and Pakistan. The resulting perspectives have been further supported by China's military assistance to Pakistan, the nuclear and missile proliferation in the subcontinent as well as the terrorist attack on the Indian Parliament. In conclusion, the general framework of the article helps us to understand the fact that India–Pakistan military engagement continues to serve Chinese strategic interest regionally as well as globally. Therefore, for India, the policy of engagement with both Pakistan and China on all fronts including trade and commerce is the best option—for the policy of engagement has been successful in mellowing down the tensions between the triangle.
Balancing China in Asia
Authors: Batabyal Anindya
Published: May 2006

This article focuses upon India's Look East Strategy, which has been a cornerstone of the country's new foreign policy orientation after the end of the Cold War. It reflects a newfound inclination on India's part to play a pre-eminent role in the affairs of the East and the Southeast Asian region. In this great game, competition and rivalry with China has become a significant component. Although relations between India and China have improved considerably over the years, long-standing mutual suspicion and animosities continue to persist over a large number of issues. A critical review of India's Look East strategy as part of her overall foreign policy in Asia reveals that one of the important objectives behind this strategy is to play a new balancing game against China in the Southeast Asian and the Asia-Pacific region. Though China has greater economic integration with the Southeast Asian region, there is still apprehension over the strategic role it will play in the future. A close scrutiny of India's Look East strategy reveals that in spite of both India and ASEAN refusing to admit so openly, the rise of China has been one of the significant factors behind the evolution and consolidation of this policy. Look East strategy is part of a grand vision in which India gets to play a prominent role in Asia and world affairs. Lord Curzon, former British Viceroy to India was the inspiration behind this vision. (The neo-Curzonians among the Indian elite are in favour of implementing a larger strategic vision for India under the present context by taking into account the new realities). In a way, the prospect of expanding Chinese power, particularly in the Southeast Asian region, seems to propel India's Look East strategy. This is part of an overall Forward policy in Asia based on the Curzonian legacy that India has embarked upon since the culmination of the Cold War. It is quite apparent that strategic competition with China is an undeclared element of India's Look East strategy. This becomes clear if one carefully evaluates recent Indian efforts to improve relations with the military regime in Myanmar, its attempt to forge sub-regional cooperation in the form of BIMSTEC, its effort to promote the Mekong-Ganga Cooperation forum, the reasons behind its inclusion in the ARF (ASEAN Regional Forum) and in the recently concluded East Asian Summit as well as the evolving strategic linkages with countries like Japan in the Asia-Pacific region.