bluuebunny/crossref_metadata_2025 huggingface dataset:
The Affective Politics of Racial Mis-interpellation
Authors: Hage Ghassan
Published: January 2011

This article is concerned with some of the ramifications of the affective dimension of Fanon’s writing. In their latest book, Commonwealth, Michael Hardt and Antonio Negri take Fanon’s attempt to transcend European universality through the struggle for a ‘new universality’ as an exemplary schema that informs their politics of alter-modernity. In the article, I show that the affective dimension of Fanon’s search for a new universality is far more anti- than alter-European, albeit in an ambivalent way. I analyse how this difference between an affective ‘anti’ and an intellectual ‘alter’ arises in Fanon’s analysis and experience of racism. I refer to this particular experience as mis-interpellation and analyse the equally particular affect it generates. More generally, I show that if one is to make use of Fanon’s work today one cannot separate the intellectual and the affective that are so intertwined in his analytical work as Hardt and Negri do. To do so is to abstract from the serious political ramifications that the presence of this affective dimension entails.
‘There Are No Blacks in France’: Fanonian Discourse, ‘the Dark Night of Slavery’ and the French Civilizing Mission Reconsidered
Authors: Vergès Françoise
Published: January 2011

During the Algerian struggle, Fanon warned us about the influence on politics of ‘the few European colonialists, powerful, intractable, those who have at all times instigated repressions, broken the French democrats, blocked every endeavor within the colonial framework to introduce a modicum of democracy into Algeria’. Is this remark still pertinent? How does Frantz Fanon help us understand current reactionary politics in France? Is his analysis of the French Left still pertinent? How does colonial discourse weigh on the postcolonial present? In this article, I explore current expressions of French postcolonial reactionary politics focusing on an event in Reunion Island, a French postcolonial territory. I argue that it is important to observe what is happening in French postcolonial territories because they remain laboratories for repressive policies and discourses. What I call the discourse of ‘French Algeria’, a mix of revisionist history, resentment, wounded narcissism and racism, embodies a political trend that seeks to counter the small progress made in rewriting history from the point of view of the colony in France.
On Visualized Vision in the Early Photographic Work of Warren Neidich
Authors: Neubauer Susanne
Published: January 2011

This article contains an analysis of Warren Neidich’s early photographic work of 1997 until 2002. These works are linked to the extensive theoretical production of the artists who connect them to the concepts of the dispositif and apparatus respectively. The article provides a close description of the parameters of four pivotal work groups of Neidich’s early practice, Brain Wash (1997), Double Vision (1997—2000), Shot Reverse Shot (2001) and Law of Loci (1998—9). These works were realized with the aid of low-tech devices stemming from neuro-ophthalmology, marking the interface between current neuro-philosophical discourses such as the plasticity of the brain, the apparati of visual, i.e. analog and digital, culture and the philosophy of memory. It is suggested that Neidich, even though he intervenes and contributes importantly to these intermingling discourses in a broad manner, is particularly interested in the degraded and infirm implementations of human vision in order to explore new sensations and habits of perception.
Eye on Bamako
Authors: Bajorek Jennifer , Haney Erin
Published: January 2011

The Rencontres de Bamako or ‘African Photography Biennial’, held in Mali’s capital city, is the only biennial devoted to photography from Africa and the only international photography festival routinely held on the African continent. Since its first edition in 1994, the event has picked up impressive momentum and has caught the attention of jet-setting curators, critics, and dealers and brought exposure and international patronage to a lucky handful of photographers. The biennial has also been controversial. Some of the reasons for this controversy are familiar and echo long-standing issues in the presentation of African art to Euro-American audiences. Other criticisms raise broader problems connected with the globalization of markets and of image culture. These are increasingly voiced by a younger generation of artists, activists, and curators who are exploring new ways of working in and with the global art market. This essay seeks to give a critical and analytical account of the biennial, through conversations with key players, and it explores emergent strategies to avoid dependence on the old North-South funding structures.
‘Begging to Be Black’
Authors: Motha Stewart
Published: January 2011

This article explores the distinction between anti-colonial longing and postcolonial becoming through a commentary on Antjie Krog’s Begging to Be Black. The epistemology and ontology of postcolonial becoming is the central concern. Begging to Be Black is a mytho-poetic narrative in which a world is imagined where King Moshoeshoe, missionaries from the 19th century, Antjie Krog and her friends and colleagues, ANC cadres, the Deleuzian philosopher Paul Patton, Nelson Mandela, Archbishop Desmond Tutu and the ANC Youth League are placed in the same narrative space where they can intermingle. And this is done to respond to a crisis of the present — the difficulties South Africans face in grappling with the legacies of colonialism and Apartheid, and the fact that there is a process of un-homing and re-homing that Krog feels white South Africans in particular need to think about more deeply. The article compares Krog’s approach to decolonization with that of the leading South African philosopher of ubuntu, Mogobe Ramose. Both Krog and Ramose offer the epistemological and ontological resources for grappling with the relationship between past, present and future in a decolonizing setting. The article examines how postcolonial critique may take place through liminal figures. Liminality is characterized as central to postcolonial becoming.
On Humanizing Abstractions
Authors: Bamyeh Mohammed A.
Published: January 2011

Revisiting Fanon’s classic theory of violence and relying on some of his case studies, this article detects the propensity to see the world in abstract formats as the source of the most malignant forms of revolutionary violence. Based on this, the article explores how abstraction may still be a healthy way of thinking, especially in a globalized and postcolonial world. Two mechanisms for handling abstraction in humane ways are proposed, both of which exclude loyalties to principles or communities so long as those could only be imagined in abstract forms. The two mechanisms of humanizing abstractions proposed here include the capacity to see local stories as manifestations or episodes of universal tales, and the ability to see one’s concrete cause in relationship to a multiplicity of world causes being acted upon in the same forum.
Enron’s perp walk: Status degradation ceremonies as narrative
Authors: Cavender Gray , Gray Kishonna , Miller Kenneth W.
Published: January 2011

The collapse of Enron and revelations about the widespread financial wrongdoing of other corporations prompted congressional hearings in 2002. The hearings culminated in the Sarbanes-Oxley Act, legislation that regulates the accounting industry and imposes prison sentences on executives who lie on their corporations’ financial statements. There was extensive media coverage of Enron and the other high-profile corporations and of the congressional hearings into their wrongdoing. In this paper, we analyze the media representations of these matters. We focus on media coverage of the political language that was offered during the hearings, on the media’s own characterizations of these events, and on how the coverage represented corporate wrongdoing and its control. Our analysis is in three parts. First, we track the ‘bad apples’ language that shifted blame from the corporations onto individuals. Second, we consider the angry denunciations from Congress that resemble status degradation ceremonies. Third, we analyze the hearings as representations of the scandal story using a critical dramaturgy. We argue that the hearings became a spectacle that deflected critique from the economy and shored up the legitimacy of the government and the economy. The usage of critical dramaturgy helps us to make sense of criminological research about the public’s sensibilities of corporate crime.
Stanley Kubrick’s A Clockwork Orange as art against torture
Authors: Strange Carolyn
Published: January 2011

Kubrick’s A Clockwork Orange ( ACO) has generated considerable debate over the effects of violence and its representation, but its depiction of torture has inspired little scholarly consideration of the film as art against torture. Produced in the early 1970s, it expressed the era’s wariness of liberal states’ potential to abuse power and to violate individual rights in the name of social good. The aversion therapy to which the main character is subjected was not the stuff of fantasy but was familiar to contemporary critics of the penal welfare complex and the covert tactics of the Cold War. ACO resonates anew in the early twenty-first century, as officially sanctioned torture, justified in the so-called Global War on Terrorism (GWOT), provides fresh cause to question what is sacrificed in the name of security.
The Code of Harry: Performing normativity in Dexter
Authors: Force William Ryan
Published: January 2011

This article explores technologies of person production used by human actors to manage interactive exchanges in ways that are understood to be accountable to and morally compatible with the social order. I specifically explore how the eponymous character of the US television series Dexter integrates conventional face-work and stigma management with 'reverse marking’ in order to present an unmarked person. Reverse marking, following Brekhus’s (1996) usage, involves perceptually attending to those aspects of identity typically regarded as mundane. I argue the role reverse marking plays in Dexter’s performance of identity draws attention to the mundane as the result of 'doing,’ grounding a critical reevaluation of the privileged cultural location of unmarkedness or normativity.
‘Trying to reach the future through the past’: Murals and memory in Northern Ireland
Authors: Rolston Bill
Published: January 2011

Ireland is sometimes said to be cursed with a surfeit of history; memory is seen as one of the principal causes of an endless cycle of violence. In contrast, this article focuses on collective memory and examines the way in which this was drawn on as a resource by republican and loyalist communities in terms of identity and endurance during almost four decades of conflict. These identities were displayed in various commemorations and symbols, including wall murals. During the peace process these murals have been judged officially to be anachronistic, leading to a recent government-funded scheme to remove them, the Reimaging Communities Programme. This article questions the political motivation of this programme. It considers the attempts by people in republican and loyalist areas to come to terms with the peace process by emphasizing traditional symbols of identity, while at the same time reinterpreting them for a new era. Symbols can be the bridge between the past and the future which makes the present tolerable.
Covering more territory to fight resistance: considering nurses’ role in antimicrobial stewardship
Authors: Edwards R. , Drumright LN , Kiernan M. , Holmes A.
Published: January 2011

The potential contribution nurses can make to the management of antimicrobials within an in-patient setting could impact on the development of antimicrobial resistance (AMR) and healthcare associated infections (HCAIs). Current initiatives promoting prudent antimicrobial prescribing and management have generally failed to include nurses, which subsequently limits the extent to which these strategies can improve patient outcomes. For antimicrobial stewardship (AS) programmes to be successful, a sustained and seamless level of monitoring and decision making in relation to antimicrobial therapy is needed. As nurses have the most consistent presence as patient carers, they are in the ideal position to provide this level of service. However, for nurses to truly impact on AMR and HCAIs through increasing their profile in AS, barriers and facilitators to adopting this enhanced role must be contextualised in the implementation of any initiative.
N-RasG12D induces features of stepwise transformation in preleukemic human umbilical cord blood cultures expressing the AML1-ETO fusion gene
Authors: Chou Fu-Sheng , Wunderlich Mark , Griesinger Andrea , Mulloy James C.
Published: January 2011

AML1-ETO (AE) is a fusion product of t(8;21) observed in 40% French-American-British M2 type of acute myeloid leukemia (AML). Clinical data suggest that Ras mutation is a frequent cooperating event in t(8;21) AML. Whether constitutively active Ras promotes leukemogenesis on the t(8;21) background has not been demonstrated experimentally. Here, we retrovirally expressed N-RasG12D in AE-expressing human hematopoieticcells to investigate cooperativity. The AE/N-RasG12D cultures were cytokine-independent, enriched for CD34 positivity, and possessed increased colony-forming and replating abilities. N-RasG12D expression led to Bcl-2 up-regulation and reduced apoptosis. Ectopic Bcl-2 expression also resulted in enhanced colony-forming and replating abilities but was insufficient to sustain cytokine independence. AE/N-RasG12D cells were more sensitive to Bcl-2 inhibition with ABT-737 than parent AE cells. Enhanced engraftment of AE/N-RasG12D cells was observed on intrafemoral injection into immunodeficient mice, presumably because of improved survival in the bone marrow microenvironment. N-RasG12D promotes progression toward transfor-mation in AE-expressing cells, partially through up-regulating Bcl-2.
HIV disease progression correlates with the generation of dysfunctional naive CD8low T cells
Authors: Favre David , Stoddart Cheryl A. , Emu Brinda , Hoh Rebecca , Martin Jeffrey N. , Hecht Frederick M. , Deeks Steven G. , McCune Joseph M.
Published: January 2011

HIV infection can result in depletion of total CD4+ T cells and naive CD8+ T cells, and in the generation of dysfunctional effector CD8+ T cells. In this study, we show that naive CD8+ T cells in subjects with progressive HIV disease express low levels of CD8α and CD8β chains. Such naive CD8low T cells display broad signaling defects across the T-cell receptor complex, and their appearance correlates with generalized up-regulation of major histocompatibility complex class I (MHC-I) antigens on peripheral blood mononuclear cells (PBMCs). To explore a causal link between increased MHC-I up-regulation and the generation of naive CD8low T cells, we used the humanized SCID-hu Thy/Liv mouse model to show that HIV infection of the thymus and interferon α (IFNα) treatment alone result in MHC-I up-regulation and in the generation of dysfunctional CD3highCD8+CD4− single-positive 8 (SP8) thymocytes with low expression of CD8. We suggest that dysfunctional naive CD8low T cells are generated as a result of IFNα-mediated up-regulation of MHC-I on stromal cells in the thymus and antigen-presenting cells in the periphery, and that dysfunction in this naive compartment contributes to the immunodeficiency of HIV disease. This study is registered at www.clinicaltrials.gov as NCT00187512.
COMP-Ang1 stimulates HIF-1α–mediated SDF-1 overexpression and recovers ischemic injury through BM-derived progenitor cell recruitment
Authors: Youn Seock-Won , Lee Sae-Won , Lee Jaewon , Jeong Han-Kyul , Suh Jung-Won , Yoon Chang-Hwan , Kang Hyun-Jae , Kim Hak-Zoo , Koh Gou-Young , Oh Byung-Hee , Park Young-Bae , Kim Hyo-Soo
Published: January 2011

Recruitment and adhesion of bone marrow (BM)–derived circulating progenitor cells to ischemic tissue are important for vasculogenesis and tissue repair. Recently, we found cartilage oligomeric matrix protein (COMP)–Ang1 is a useful cell-priming agent to improve the therapeutic efficacy of progenitor cells. However, the effect and the underlying mechanisms of COMP-Ang1 on recruitment of BM-derived progenitor cells (BMPCs) to foci of vascular injury have not been well defined. Here, we found that COMP-Ang1 is a critical stimulator of stromal cell–derived factor 1 (SDF-1), the principal regulator of BM-cell trafficking. Furthermore, SDF-1 stimulation by COMP-Ang1 was blocked by small-interfering RNA (siRNA) against hypoxia-inducible factor-1α (HIF-1α). COMP-Ang1 increased the synthesis of HIF-1α by activating mammalian target of rapamycin (mTOR) in hypoxic endothelium. The intermediate mechanism transmitting the COMP-Ang1 signal to the downstream mTOR/HIF-1α/SDF-1 pathway was the enhanced binding of the Tie2 receptor with integrin-linked kinase (ILK), an upstream activator of mTOR. In the mouse ischemic model, local injection of COMP-Ang1 stimulated the incorporation of BMPCs into ischemic limb, thereby enhancing neovasculogenesis and limb salvage. Collectively, our findings identify the COMP-Ang1/HIF-1α/SDF-1 pathway as a novel inducer of BMPC recruitment and neovasculogenesis in ischemic disease.
Identification of microRNAs in the cerebrospinal fluid as marker for primary diffuse large B-cell lymphoma of the central nervous system
Authors: Baraniskin Alexander , Kuhnhenn Jan , Schlegel Uwe , Chan Andrew , Deckert Martina , Gold Ralf , Maghnouj Abdelouahid , Zöllner Hannah , Reinacher-Schick Anke , Schmiegel Wolff , Hahn Stephan A. , Schroers Roland
Published: January 2011

The diagnosis of primary central nervous system lymphoma (PCNSL) depends on histopathology of brain biopsies, because disease markers in the cerebrospinal fluid (CSF) with sufficient diagnostic accuracy are not available yet. MicroRNAs (miRNAs) are regulatory RNA molecules that are deregulated in many disease types, including cancer. Recently, miRNAs have shown promise as markers for cancer diagnosis. In this study, we demonstrate that miRNAs are present in the CSF of patients with PCNSL. With a candidate approach and miRNA quantification by reverse transcription polymerase chain reaction, miRNAs with significant levels in the CSF of patients with PCNSL were identified. MiR-21, miR-19, and miR-92a levels in CSF collected from patients with PCNSL and from controls with inflammatory CNS disorders and other neurologic disorders indicated a significant diagnostic value of this method. Receiver-operating characteristic analyses showed area under the curves of 0.94, 0.98, and 0.97, respectively, for miR-21, miR-19, and miR-92a CSF levels in discriminating PCNSL from controls. More importantly, combined miRNA analyses resulted in an increased diagnostic accuracy with 95.7% sensitivity and 96.7% specificity. We also demonstrated a remarkable stability of miRNAs in the CSF. In conclusion, CSF miRNAs are potentially useful tools as novel noninvasive biomarker for the diagnosis of PCNSL.
Epigenetic control of IRF1 responses in HIV-exposed seronegative versus HIV-susceptible individuals
Authors: Su Ruey-Chyi , Sivro Aida , Kimani Joshua , Jaoko Walter , Plummer Francis A. , Ball T. Blake
Published: January 2011

Not all individuals exposed to HIV become infected. Understanding why these HIV-exposed seronegative individuals remain uninfected will help inform the development of preventative measures against HIV infection. Interferon regulatory factor-1 (IRF1) plays a critical role both in host antiviral immunity and in HIV-1 replication. This study examined IRF1 expression regulation in the ex vivo peripheral blood mononuclear cells of HIV-exposed seronegative commercial sex workers who can be epidemiologically defined as relatively resistant to HIV infection (HIV-R), versus HIV-uninfected, susceptible controls (HIV-S). Whereas HIV-susceptible individuals demonstrated a biphasic, prolonged increase in IRF1 expression after interferon-γ stimulation, HIV-R individuals demonstrated a robust, but transient response. We also found that the IRF1 promoter in HIV-R was primed by increased basal histone deacetylase-2 binding, independently of transcription regulators, STAT1 and nuclear factor-κB/p65, implicating an epigenetic silencing mechanism. Interestingly, the transitory IRF1 response in HIV-R was sufficient in comparable regulation of interleukin-12 and interleukin-4 expression compared with the HIV-susceptible controls. This is the first study characterizing IRF1 responsiveness in individuals who demonstrate altered susceptibility to HIV infection. These data suggest that transitory IRF1 responsiveness in HIV-R may be one of the key contributors to the altered susceptibility to HIV infection during the early stages of primary HIV infection.
How I treat myelofibrosis
Authors: Tefferi Ayalew
Published: January 2011

It is currently assumed that myelofibrosis (MF) originates from acquired mutations that target the hematopoietic stem cell and induce dysregulation of kinase signaling, clonal myeloproliferation, and abnormal cytokine expression. These pathogenetic processes are interdependent and also individually contributory to disease phenotype–bone marrow stromal changes, extramedullary hematopoiesis, ineffective erythropoiesis, and constitutional symptoms. Molecular pathogenesis of MF is poorly understood despite a growing list of resident somatic mutations that are either functionally linked to Janus kinase (JAK)–signal transducer and activator of transcription hyperactivation (eg JAK2, MPL, and LNK mutations) or possibly involved in epigenetic dysregulation of transcription (TET2, ASXL1, or EZH2 mutations). Current prognostication in primary MF is based on the Dynamic International Prognostic Scoring System-plus model, which uses 8 independent predictors of inferior survival to classify patients into low, intermediate 1, intermediate 2, and high-risk disease groups; corresponding median survivals are estimated at 15.4, 6.5, 2.9, and 1.3 years. Such information is used to plan a risk-adapted treatment strategy for the individual patient, which might include observation alone, conventional or investigational (eg, JAK inhibitors, pomalidomide) drug therapy, allogenic stem cell transplantation with reduced- or conventional-intensity conditioning, splenectomy, or radiotherapy. I discuss these treatment approaches in the context of who should get what and when.
Apparent dip and apparent anisotropy from multifrequency triaxial induction measurements
Authors: Hagiwara Teruhiko
Published: January 2011

The triaxial (or multicomponent) induction log is used to measure not only the resistivity anisotropy of an anisotropic formation but also the relative dip of the tool with respect to the formation. The anisotropic resistivity and the relative dip of layered formations are also inverted from the triaxial induction-log measurements at a depth by assuming a homogeneous anisotropic formation or at multiple depths by assuming a multilayered formation model. When the triaxial induction log is run at multiple frequencies, multifrequency focusing can be applied to the log measurements. Then, the apparent dip is algebraically defined from the frequency-focused triaxial induction measurements at a depth. The apparent dip yields the true dip in an anisotropic formation. The algebraically calculated apparent dip may be used to determine the effective dip in layered formations. The apparent dip yields the true dip in thinly bedded formations. The apparentdip also yields the true dip in thick anisotropic formations. However, the apparent dip yields a smaller dip than the true dip when the anisotropy is small (the anisotropy effect). It yields a much smaller dip in thick isotropic formations. Like the apparent dip, the apparent anisotropy is algebraically defined from the frequency-focused triaxial induction measurements at a depth. The apparent anisotropy yields the true anisotropy in an anisotropic formation. The algebraically calculated apparent anisotropy may be applied to layered formations. The apparent anisotropic resistivity (horizontal and vertical) can likewise be determined algebraically from the frequency-focused triaxial data. In contrast to the apparent dip, which yields the true dip in thinly bedded formations but not in thicker formations, the apparent anisotropy yields the true anisotropy in thick anisotropic formations but not in thinner anisotropic formations. The apparent anisotropy is affected by the shoulder-bed anisotropy when the formation is not thick (the shoulder-bed effect).
Focused-source electromagnetic survey versus standard CSEM: 3D modeling in complex geometries
Authors: Davydycheva Sofia , Rykhlinski Nikolai
Published: January 2011

A novel focused-source electromagnetic (FSEM) method focuses the EM field in the vertical direction to provide deep-reading resistivity data. FSEM offers better spatial resolution and greater depth of investigation than the conventional controlled-source electromagnetic (CSEM) method for land and marine EM surveys. We have proven the high efficiency of FSEM by analyzing 3D models of various complex geologic formations in the presence of seafloor bathymetry, shallow resistive gas-hydrate overburdens, and secondary gas reservoirs formed above deeper oil reservoirs. Combining the power of our focusing technique with the power of our 3D numerical modeling method, we have developed exceptionally challenging test cases to conclude that FSEM automatically cancels unwanted shallow effects and allows simple visual interpretation of deep reservoir responses. In addition, FSEM is insensitive to imperfections in the setup geometry. We achieve these advantages using a proper combination of measurements acquired in the receiver excited by transmitters situated at different space points. The method is promising in anisotropic formations as well.
Quantification of modeling errors in airborne TEM caused by inaccurate system description
Authors: Christiansen Anders Vest , Auken Esben , Viezzoli Andrea
Published: January 2011

Being able to recover accurate and quantitative descriptions of the subsurface electrical conductivity structure from airborne electromagnetic data is becoming more and more crucial in many applications such as hydrogeophysical and environmental mapping, but also for mining exploration. The effect on the inverted models of inaccurate system description in the 1D forward modeling of helicopter time-domain electromagnetic (TEM) data was studied. The most important system parameters needed for accurate description of the subsurface conductivity were quantified using a nominal airborne TEM system and three different reference models to ensure the generality of the conclusions. By calculating forward responses, the effect of changing the system transfer function of the nominal airborne TEM system was studied in detail. The data were inverted and the consequences of inaccurate modeling of the system transfer function were studied inthe model space. Errors in the description of the transfer function influence the inverted model differently. The low-pass filters, current turn-off, and receiver-transmitter (Rx-Tx) timing issues primarily influenced the early time gates. The waveform repetition, gate integration, altitude, and geometry mainly influenced the late time gates. Depth of investigation is highly model dependent, but in general the early times hold information on the shallower parts of the model and the late times hold information on the deeper parts of the model. Amplitude, gain, and current variations affect the entire sounding and therefore the entire model. The results showed that all of these parameters should be measured and modeled accurately during inversion of airborne TEM data. If not, the output model can differ quite dramatically from the true model. Layer boundaries can be inaccurate by tens of meters, and layer resistivities by as much as an order of magnitude. In the worst cases, the measured data simply cannot be fitted within noise level.
Quantifying solute transport processes: Are chemically “conservative” tracers electrically conservative?
Authors: Singha Kamini , Li Li , Day-Lewis Frederick D. , Regberg Aaron B.
Published: January 2011

The concept of a nonreactive or conservative tracer, commonly invoked in investigations of solute transport, requires additional study in the context of electrical geophysical monitoring. Tracers that are commonly considered conservative may undergo reactive processes, such as ion exchange, thus changing the aqueous composition of the system. As a result, the measured electrical conductivity may reflect not only solute transport but also reactive processes. We have evaluated the impacts of ion exchange reactions, rate-limited mass transfer, and surface conduction on quantifying tracer mass, mean arrival time, and temporal variance in laboratory-scale column experiments. Numerical examples showed that (1) ion exchange can lead to resistivity-estimated tracer mass, velocity, and dispersivity that may be inaccurate; (2) mass transfer leads to an overestimate in the mobile tracer mass and an underestimate in velocity when using electrical methods; and (3) surface conductance does not notably affect estimated moments when high-concentration tracers are used, although this phenomenon may be important at low concentrations or in sediments with high and/or spatially variable cation-exchange capacity. In all cases, colocated groundwater concentration measurements are of high importance for interpreting geophysical data with respect to the controlling transport processes of interest.
TIV contrast source inversion of mCSEM data
Authors: Wiik Torgeir , Løseth Lars Ole , Ursin Bjørn , Hokstad Ketil
Published: January 2011

We present a 3D contrast source inversion scheme for electromagnetic data in conductive media. We consider only contrasts in electric conductivity but allow the medium to be transversely isotropic in the vertical direction. This has applications in, for instance, inversion of marine controlled-source electromagnetic data. The contrast source inversion (CSI) method is based on the integral equation formulation of electromagnetic field propagation and solves the inverse problem of determining the conductivity structure of the subsurface. The method minimizes a cost functional that enforces both data fidelity and that the solution satisfy the Lippmann-Schwinger equation. Further regularization is introduced linearly into the cost functional to incorporate prior model information. Although the problem is nonlinear, the chosen strategy splits the minimization problem into two linear problems, which are solved alternatingly. To this end, contrast sources are introduced, which may be interpreted as sources emitting the scattered field from a scattering object. Two synthetic and two real field examples are inverted, which demonstrates the method and how the transversely isotropic in the vertical direction (TIV) inversion performs compared with isotropic inversion. The CSI method is found to be applicable to real field examples, and the results show that a TIV inversion is preferred over isotropic to identify weak anomalies in these examples. The reason for this is that both the horizontal and vertical conductivity affects the signal propagation in the overburden.
In the twilight zone: adolescent capacity in the criminal justice arena
Authors: Sarkar Sameer P.
Published: January 2011

The rights and duties of an adolescent has been the focus of much controversy, especially in the field of capacity and consent, and to a lesser extent in youth justice. Society is constantly reviewing how to ensure fairness to all, while not denying anyone their rights. Developments in neurobiology have forced us to rethink age-old concepts about adolescent development within competence and culpability. This article focuses on the theoretical foundations of capacity or competence and provides guidance on how to negotiate common clinical pitfalls when assessing capacity in an adolescent.
Mental health in children with severe hearing impairment
Authors: Gentili Nicoletta , Holwell Andrew
Published: January 2011

Deafness does not in itself cause emotional/behavioural or cognitive problems or psychiatric disorders. However, children with hearing impairment are at greater risk of developing emotional/behavioural problems and neurodevelopmental disorders. The incidence of both seems to be higher in deaf children from hearing families. Most prelingual deafness is caused by recessive genes; hence, most deaf individuals come from hearing families, the majority of whom do not use sign language. Numerous studies, in both hearing and deaf populations, show how the lack of access to language has an impact on the emotional development of children. This article focuses on the mechanisms by which early language deprivation mediates emotional/behavioural difficulties and consequent emotional dysregulation, and may produce behaviours and symptoms that can be misdiagnosed as neurodevelopmental disorders in deaf children and adolescents (from infancy to 18 years of age).
Mode of action of electroconvulsive therapy: an update
Authors: Scott Allan I. F.
Published: January 2011

It has become acceptable for psychiatrists to say that they simply do not know how electroconvulsive therapy (ECT) works. This frame of mind runs the risk that there will be no expectation that psychiatrists remain familiar with seminal studies on the mode of action of ECT. This article is intended as a reminder of these studies and illustrates how the original theories have evolved. This evolution has been brought about largely by modern brain imaging techniques in human studies and in patients treated with ECT. These new findings will be set in the context of contemporary ideas about the neuroanatomy of mood disorders and the cellular mechanisms of the long-term effects of antidepressant treatments.
Clozapine and blood dyscrasia
Authors: Latif Zahid , Jabbar Faraz , Kelly Brendan D.
Published: January 2011

Clozapine is an effective antipsychotic medication but is associated with agranulocytosis, neutropenia and leucopenia. The reintroduction of clozapine improved management of treatment-resistant schizophrenia, yet resulted in a paradoxical situation whereby the risk of blood dyscrasias is rigorously managed but other adverse effects (e.g. seizures, cardiovascular complications) are less well monitored. Monitoring of weight, lipids, plasma glucose and other metabolic parameters is recommended. There is also a need to reconsider routine haematological monitoring with other medications associated with blood dyscrasia (e.g. phenothiazines, carbamazepine). In particular, individuals who develop clozapine-induced blood dyscrasia may require haematological monitoring during treatment with other antipsychotics.
Validity, utility and acceptability of borderline personality disorder diagnosis in childhood and adolescence: survey of psychiatrists
Authors: Griffiths Mark
Published: January 2011

Aims and method

To establish the views of child and adolescent psychiatrists (n= 52) regarding the conceptual and empirical validity, clinical utility and acceptability of the diagnosis of borderline personality disorder in child and adolescent populations. A questionnaire survey was carried out.

Results

The child and adolescent psychiatrists' perception of the validity of borderline personality disorder for adult populations was relatively high (82% felt it to be valid). Significantly fewer of those considered borderline personality disorder to be valid for adolescent populations (37%). Strikingly different results were obtained when the questions related to child (<12 years) populations (2%).

Clinical implications

Given the views expressed by these consultant child and adolescent psychiatrists, it would seem appropriate to approach with caution suggestions that the borderline personality disorder category should have extended use with adolescent and child populations.
Continuous Mixtures of Exponentials and IFR Gammas Having Bathtub-Shaped Failure Rates
Authors: Block Henry W. , Langberg Naftali A. , Savits Thomas H. , Wang Jie
Published: January 2011

It can be seen that a mixture of an exponential distribution and a gamma distribution with increasing failure rate for the right choice of parameters can yield a distribution with a bathtub-shaped failure rate. In this paper we consider a continuous mixture of exponentials and a continuous mixture of gammas with increasing failure rates and show that the resulting mixture has a bathtub-shaped failure rate.
Some New Results on the Moment Generating Function Order and Related Life Distributions
Authors: Zhang Shuhong , Li Xiaohu
Published: January 2011

In this paper we study the moment generating function order and the new better than used in the moment generating function order (NBUMG) life distributions. A closure property of this order under an independent random sum is deduced, and stochastic comparisons among the block replacement policy, the age replacement policy, the complete repair policy, and the minimal repair policy of an NBUMG component are investigated.
Total Variation Approximation for Quasi-Stationary Distributions
Authors: Barbour A. D. , Pollett P. K.
Published: January 2011

Quasi-stationary distributions, as discussed in Darroch and Seneta (1965), have been used in biology to describe the steady state behaviour of population models which, while eventually certain to become extinct, nevertheless maintain an apparent stochastic equilibrium for long periods. These distributions have some drawbacks: they need not exist, nor be unique, and their calculation can present problems. In this paper, we give biologically plausible conditions under which the quasi-stationary distribution is unique, and can be closely approximated by distributions that are simple to compute.
Multiobjective Stopping Problem for Discrete-Time Markov Processes: Convex Analytic Approach
Authors: Dufour F. , Piunovskiy A. B.
Published: January 2011

The purpose of this paper is to study an optimal stopping problem with constraints for a Markov chain with general state space by using the convex analytic approach. The costs are assumed to be nonnegative. Our model is not assumed to be transient or absorbing and the stopping time does not necessarily have a finite expectation. As a consequence, the occupation measure is not necessarily finite, which poses some difficulties in the analysis of the associated linear program. Under a very weak hypothesis, it is shown that the linear problem admits an optimal solution, guaranteeing the existence of an optimal stopping strategy for the optimal stopping problem with constraints.
A Markov Chain Analysis of Genetic Algorithms: Large Deviation Principle Approach
Authors: Suzuki Joe
Published: January 2011

In this paper we prove that the stationary distribution of populations in genetic algorithms focuses on the uniform population with the highest fitness value as the selective pressure goes to ∞ and the mutation probability goes to 0. The obtained sufficient condition is based on the work of Albuquerque and Mazza (2000), who, following Cerf (1998), applied the large deviation principle approach (Freidlin-Wentzell theory) to the Markov chain of genetic algorithms. The sufficient condition is more general than that of Albuquerque and Mazza, and covers a set of parameters which were not found by Cerf.
A Markov Model for the Spread of Viruses in an Open Population
Authors: Coutin L. , Decreusefond L. , Dhersin J. S.
Published: January 2011

Inspired by methods of queueing theory, we propose a Markov model for the spread of viruses in an open population with an exogenous flow of infectives. We apply it to the diffusion of AIDS and hepatitis C diseases among drug users. From a mathematical point of view, the difference between the two viruses is shown in two parameters: the probability of curing the disease (which is 0 for AIDS but positive for hepatitis C) and the infection probability, which seems to be much higher for hepatitis. This model bears some resemblance to the M/M/∞ queueing system and is thus rather different from the models based on branching processes commonly used in the epidemiological literature. We carry out an asymptotic analysis (large initial population) and show that the Markov process is close to the solution of a nonlinear autonomous differential system. We prove both a law of large numbers and a functional central limit theorem to determine the speed of convergence towards the limiting system. The deterministic system itself converges, as time tends to ∞, to an equilibrium point. We then show that the sequence of stationary probabilities of the stochastic models shrinks to a Dirac measure at this point. This means that in a large population and for long-term analysis, we may replace the individual-based microscopic stochastic model with the macroscopic deterministic system without loss of precision. Moreover, we show how to compute the sensitivity of any functional of the Markov process with respect to a slight variation of any parameter of the model. This approach is applied to the spread of diseases among drug users, but could be applied to many other case studies in epidemiology.
Shortfall Risk Approximations for American Options in the Multidimensional Black-Scholes Model
Authors: Dolinsky Yan
Published: January 2011

We show that shortfall risks of American options in a sequence of multinomial approximations of the multidimensional Black-Scholes (BS) market converge to the corresponding quantities for similar American options in the multidimensional BS market with path-dependent payoffs. In comparison to previous papers we consider the multiassets case for which we use the weak convergence approach.
Characterizing Attainable Claims: A New Proof
Authors: Tehranchi Michael R.
Published: January 2011

This short note offers a new proof of the following fact: in a discrete-time arbitrage-free market model, a contingent claim is attainable if and only if its expected value is the same under all equivalent martingale measures. The proof is based on Rogers' (1994) proof of the Dalang-Morton-Willinger (1990) theorem.
Markov-Modulated Brownian Motion with Two Reflecting Barriers
Authors: Ivanovs Jevgenijs
Published: January 2011

We consider a Markov-modulated Brownian motion reflected to stay in a strip [0,B]. The stationary distribution of this process is known to have a simple form under some assumptions. We provide a short probabilistic argument leading to this result and explain its simplicity. Moreover, this argument allows for generalizations including the distribution of the reflected process at an independent, exponentially distributed epoch. Our second contribution concerns transient behavior of the model. We identify the joint law of the processes defining the model at inverse local times.
Linear and Nonlinear Boundary Crossing Probabilities for Brownian Motion and Related Processes
Authors: Fu James C. , Wu Tung-Lung
Published: January 2011

We propose a new method to obtain the boundary crossing probabilities or the first passage time distribution for linear and nonlinear boundaries for Brownian motion. The method also covers certain classes of stochastic processes associated with Brownian motion. The basic idea of the method is based on being able to construct a finite Markov chain, and the boundary crossing probability of Brownian motion is cast as the limiting probability of the finite Markov chain entering a set of absorbing states induced by the boundaries. Error bounds are obtained. Numerical results for various types of boundary studied in the literature are provided in order to illustrate our method.
A General ‘Bang-Bang’ Principle for Predicting the Maximum of a Random Walk
Authors: Allaart Pieter
Published: January 2011

Let (Bt)0≤t≤T be either a Bernoulli random walk or a Brownian motion with drift, and let Mt := max{Bs: 0 ≤ s ≤ t}, 0 ≤ t ≤ T. In this paper we solve the general optimal prediction problem sup0≤τ≤TE[f(MT − Bτ], where the supremum is over all stopping times τ adapted to the natural filtration of (Bt) and f is a nonincreasing convex function. The optimal stopping time τ* is shown to be of ‘bang-bang’ type: τ* ≡ 0 if the drift of the underlying process (Bt) is negative and τ* ≡ T if the drift is positive. This result generalizes recent findings of Toit and Peskir (2009) and Yam, Yung and Zhou (2009), and provides additional mathematical justification for the dictum in finance that one should sell bad stocks immediately, but keep good stocks as long as possible.
Odds Theorem with Multiple Selection Chances
Authors: Ano Katsunori , Kakinuma Hideo , Miyoshi Naoto
Published: January 2011

We study the multi-selection version of the so-called odds theorem by Bruss (2000). We observe a finite number of independent 0/1 (failure/success) random variables sequentially and want to select the last success. We derive the optimal selection rule when m (≥ 1) selection chances are given and find that the optimal rule has the form of a combination of multiple odds-sums. We provide a formula for computing the maximum probability of selecting the last success when we have m selection chances and also provide closed-form formulae for m = 2 and 3. For m = 2, we further give the bounds for the maximum probability of selecting the last success and derive its limit as the number of observations goes to ∞. An interesting implication of our result is that the limit of the maximum probability of selecting the last success for m = 2 is consistent with the corresponding limit for the classical secretary problem with two selection chances.
On the FirstkMoments of the Random Count of a Pattern in a Multistate Sequence Generated by a Markov Source
Authors: Nuel G.
Published: January 2011

In this paper we develop an explicit formula that allows us to compute the firstkmoments of the random count of a pattern in a multistate sequence generated by a Markov source. We derive efficient algorithms that allow us to deal with any pattern (low or high complexity) in any Markov model (homogeneous or not). We then apply these results to the distribution of DNA patterns in genomic sequences, and we show that moment-based developments (namely Edgeworth's expansion and Gram-Charlier type-B series) allow us to improve the reliability of common asymptotic approximations, such as Gaussian or Poisson approximations.
Large Cliques in a Power-Law Random Graph
Authors: Janson Svante , Łuczak Tomasz , Norros Ilkka
Published: January 2011

In this paper we study the size of the largest clique ω(G(n, α)) in a random graph G(n, α) on n vertices which has power-law degree distribution with exponent α. We show that, for ‘flat’ degree sequences with α > 2, with high probability, the largest clique in G(n, α) is of a constant size, while, for the heavy tail distribution, when 0 < α < 2, ω(G(n, α)) grows as a power of n. Moreover, we show that a natural simple algorithm with high probability finds in G(n, α) a large clique of size (1 − o(1))ω(G(n, α)) in polynomial time.
Limit Theorems for the Inductive Mean on Metric Trees
Authors: Basrak Bojan
Published: January 2011

For random variables with values on binary metric trees, the definition of the expected value can be generalized to the notion of a barycenter. To estimate the barycenter from tree-valued data, the so-called inductive mean is constructed recursively using the weighted interpolation between the current mean and a new data point. We show the strong consistency of the inductive mean, but also that it, somewhat peculiarly, converges towards the true barycenter with different rates, and asymptotic distributions depending on the small variations of the underlying distribution.