bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional hermaphroditism in teleosts
Authors: De Mitcheson Yvonne Sadovy , Liu Min
Published: February 2008

Teleost fishes are characterized by a diversity of sexual patterns. Hermaphroditism, the expression of both male and female reproductive function in a single individual, generates the most curiosity and controversy. Yet diagnosis of this form of sexuality continues to challenge workers, in particular the distinction between functional and non‐functional hermaphroditism. This distinction, reflected as it is in the relationships between gonad form and function, is important if we wish to improve our understanding of the origin of hermaphroditism in the teleosts and of its highly sporadic expression today. Although structure can indicate phylogenetic affinities, it does not always reflect reproductive function, and function is important for understanding adaptation. With resurgent interest in hermaphroditism comes the recognition that understanding sexual pattern is not only important for better knowledge of reproductive biology and ecology but may also elucidate phylogenetic relationships. On the basis of a conservative and clearly defined set of diagnostic criteria, which incorporate new accounts of hermaphroditic species, and by applying an improved understanding of gonadal ontogeny, a comprehensive review and careful re‐examination of all primary literature was conducted. This overview documents the incidence of hermaphroditism in teleosts and explores its phylogenetic distribution, possible origin and range of expression. The review confirms functional hermaphroditism in 27 teleost families in seven orders, predominantly among tropical, marine perciforms in which its diversity of expression is greatest. In families with functional hermaphrodites, the sexual pattern is widespread and often highly variable in expression, even within a single genus or between populations. Based on our understanding of gonadal ontogeny in teleosts and on known phylogenetic interrelationships, the origin of functional hermaphroditism is most parsimoniously explained by a proto‐hermaphroditic condition in teleosts and cyclostomes, constituting a hermaphroditic potential for these groups. Exploitation and expression of this potential appear to be a response to a suite of environmental and biological factors, opportunities and constraints that result in the independent appearance of the hermaphroditic option in many different fish lineages.
PARCHING THE LAND?: THE CHETTIARS IN BURMA
Authors: Turnell Sean , Vicary Alison
Published: February 2008

In the history of Burma's economy, few groups have been as vilified as the Chettiars. A community of Indian moneylenders, the Chettiars were crucial agents in transforming Burma into the rice bowl of Asia. Following the global depression of the 1930s, Burmese agriculture became severely distressed and wide‐scale loan default saw the transfer of much of Burma's cultivatable land to the Chettiars, who were demonised and made scapegoats for the vices of colonialism. The paper draws on the ‘information‐theoretic revolution’ in economics to reappraise the role of the Chettiars in Burma. We conclude the Chettiars merit history's better judgement.
The Impact of Mergers and Acquisitions on the Efficiency of the US Banking Industry: Further Evidence
Authors: Al‐Sharkas Adel A. , Hassan M. Kabir , Lawrence Shari
Published: February 2008

Abstract:  Using the Stochastic Frontier Approach (SFA), this study investigates the cost and profit efficiency effects of bank mergers on the US banking industry. We also use the non‐parametric technique of Data Envelopment Analysis (DEA) to evaluate the production structure of merged and non‐merged banks. The empirical results indicate that mergers have improved the cost and profit efficiencies of banks. Further, evidence shows that merged banks have lower costs than non‐merged banks because they are using the most efficient technology available (technical efficiency) as well as a cost minimizing input mix (allocative efficiency). The results suggest that there is an economic rational for future mergers in the banking industry. Finally, mergers may allow the banking industry to take advantage of the opportunities created by improved technology.
The Motivation for Takeovers in the UK
Authors: Hodgkinson Lynn , Partington Graham H.
Published: February 2008

Abstract:  The motives for takeovers in the UK are investigated by examining the correlations between wealth gains for the target and both acquirer wealth gains and total wealth gains. The results are sensitive to whether the gains are measured over a long or short window, the method of measuring abnormal returns, and whether controls are included for the form of the bid consideration and the sign of total bid gains. There is evidence of bids motivated by synergy, but there is also evidence of the presence of hubris and weak evidence of bids with an agency motivation. Once controls for bid consideration and the sign of total gains are introduced the explanatory power of the models increases substantially and diversity of results about bid motivation also increases.
Influence of environmental factors on stomatal development
Authors: Casson Stuart , Gray Julie E.
Published: February 2008

Stomata play a pivotal role in the regulation of gas exchange in flowering plants and are distributed throughout the aerial epidermis. In leaves, the pattern of stomatal distribution is highly variable between species but is regulated by a mechanism that maintains a minimum of one cell spacing between stomata. In Arabidopsis, a number of the genetic components of this mechanism have been identified and include, SDD1, EPF1 and the putative receptors TMM and the ERECTA‐gene family. A mitogen‐activated protein (MAP) kinase signalling cascade is believed to act downstream of these putative receptors while a number of transcription factors including SPCH, MUTE and FAMA have been identified that control consecutive steps of stomatal development. The environment also has significant effects on stomatal development. In a number of species both light intensity and CO2 concentrations have been shown to influence the frequency at which stomata develop on leaves. Long‐distance signalling mechanisms have been implicated in these environmental responses with the conditions sensed by mature leaves determining the stomatal frequency in developing leaves. Thus, changes in the environment appear to act by modulating the developmental and patterning pathways to determine stomatal frequency.

Contents

Summary
1

I.
Introduction
2

II.
Stomatal patterning in leaves
2

III.
The genetic control of stomatal development
4

IV.
The cell cycle and stomatal development
7

V.
Environmental influences on stomatal pattern
8

VI.
Systemic signals and stomatal development
10

VII.
Conclusions
11

Acknowledgements
12

References
12
Effect of rock fragment cover on interrill soil erosion from bare soils in Western Andalusia, Spain
Authors: Martínez‐Zavala L. , Jordán A.
Published: February 2008

It is known that rock fragments on the surface of soils can enhance infiltration and protect the soil against rainfall erosion. However, the effect of rock fragments in natural forest soils is less well understood. In this article, we studied the influence of rock fragment cover on run‐off, infiltration and interrill soil erosion under simulated rainfall on natural bare soils in a Spanish dehesa (managed holm oak woodland). We studied 60 plots with different rock fragment cover ranging from 3% to 85% under three simulated rainfall intensities (50, 100 and 150 mm/h). Surface run‐off appeared later and sediment yield values were smaller in soils with greater rock fragment cover. Rock fragment cover also increased infiltration rates. The final infiltration rates were 54–98% at a rainfall intensity of 50 mm/h, 31–88% at 100 mm/h and 20–80% at 150 mm/h. The interrill soil loss rates were decreased by rock fragment cover and increased with rainfall intensity. The soil loss rate was always small (0.02–1 Mg ha/h) when rock fragment cover was 75% or more. Rock fragment cover was related to soil loss rate by an exponential function.
Circalunar and ultralunar periodicities in women with partial seizures
Authors: Quigg Mark , Fowler Kristen M. , Herzog Andrew G. ,   the NIH Progesterone Trial Study Group
Published: February 2008

Summary

Purpose: Little consensus exists for the definition of catamenial epilepsy. Few studies have evaluated the periodicity of seizures to test the hypothesis that seizures in women have periodic patterns of occurrence independent of a priori hormonal considerations. In the present study, we determined seizure periodicity according to a “menstrual clock” provided by a common phase marker of the onset of menses.

Methods: Seizure and menstrual diaries of ∼3 months duration were obtained from women enrolled in a trial of hormonal therapy for localization‐related epilepsy. Midluteal progesterone levels identified ovulatory (≥5 ng/ml, OC) from anovulatory cycles (AC). Individual cycles were normalized to a common phase and period (day 0 = menses onset, intervening days = 28 bins). Periodicity of combined data was estimated with cosinor‐nonlinear least squares analysis. Best‐fit rhythms were estimated with 95% confidence limits.

Results: 100 patients provided 3344 seizures within 293 cycles (77% OC, 20% AC, indeterminate 3%). OC seizures displayed a circalunar rhythm with peak phase of occurrence at onset of menses. AC seizures also featured a circalunar rhythm that peaked at menses onset but also had ultralunar rhythms of ∼14 and ∼9 days.

Discussion: Seizures in women with epilepsy occur in circalunar rhythms. OC and AC seizures differ in seizure timing with the latter occurring in ultralunar rhythms in addition to the predominant circalunar rhythm. This finding supports the existence of catamenial epilepsy and differences in patterns of seizure occurrence between OC and AC.
The maestro don Gonzalo Rodríguez‐Lafora
Authors: Nanduri Anish S. , Kaushal Neal , Clusmann Hans , Binder Devin K.
Published: February 2008

Summary

Gonzalo Rodríguez‐Lafora (1886–1971) was an influential Spanish neurologist, and has been called the last of Cajal's great Spanish disciples. Of course, he is best known now for describing (in 1911) the intracytoplasmic inclusion bodies in “Lafora disease.” In total, he published ∼200 papers covering a wide range of subjects in neurology, psychiatry, and neuropathology. He made seminal contributions not only to the clinical and scientific literature but also to the training of many noted disciples who paid him due homage as a true “maestro.” Throughout his intellectual endeavors, Lafora manifested a singular purpose and intensity and a burning devotion to scientific honesty.
Effects of the Home Learning Environment and Preschool Center Experience upon Literacy and Numeracy Development in Early Primary School
Authors: Melhuish Edward C. , Phan Mai B. , Sylva Kathy , Sammons Pam , Siraj‐Blatchford Iram , Taggart Brenda
Published: February 2008

This study investigates the influence of aspects of home and preschool environments upon literacy and numeracy achievement at school entry and at the end of the 3rd year of school. Individuals with unexpected performance pathways (by forming demographically adjusted groups: overachieving, average, and underachieving) were identified in order to explore the effects of the home learning environment and preschool variables on child development. Multilevel models applied to hierarchical data allow the groups that differ with regard to expected performance to be created at the child and preschool center levels. These multilevel analyses indicate powerful effects for the home learning environment and important effects of specific preschool centers at school entry. Although reduced, such effects remain several years later.
Exploring the Roles of Extracurricular Activity Quantity and Quality in the Educational Resilience of Vulnerable Adolescents: Variable‐ and Pattern‐Centered Approaches
Authors: Peck Stephen C. , Roeser Robert W. , Zarrett Nicole , Eccles Jacquelynne S.
Published: February 2008

This longitudinal study examines how extracurricular activity involvement contributes to “educational resilience”—the unexpected educational attainments of adolescents who are otherwise vulnerable to curtailed school success due to personal‐ and social‐level risks. Educationally vulnerable youth characterized by significant risks and an absence of assets were identified during early adolescence (approximately age 14) using measures of academic motivation, achievement, and mental health as well as family, school, and peer contexts. Using a mixture of variable‐ and pattern‐centered analytic techniques, we investigate how both the total amount time that vulnerable youth spent in positive extracurricular activities and the specific pattern of their extracurricular activity involvement during late adolescence (approximately age 17) predict their subsequent enrollment in college during early adulthood (up through approximately age 21). Educational resilience was predicted uniquely by some, but not all, activity patterns. These results suggest that positive extracurricular activity settings afford vulnerable youth developmentally appropriate experiences that promote educational persistence and healthy development.
Mapping Swedish Females' Educational Pathways in Terms of Academic Competence and Adjustment Problems
Authors: Trost Kari , El‐Khouri Bassam Michel
Published: February 2008

Patterns of academic competence, externalizing problems, and internalizing problems were examined in females from the longitudinal Individual Development and Adaptation (IDA) program in order to understand unexpected patterns of educational attainment and problems in adulthood. Person‐oriented methods were used to identify patterns of competence and problems at ages 10, 13, and 43. These patterns were linked across time to reveal expected and unexpected educational pathways from childhood to adulthood. Most later patterns were consistent with earlier patterns of competence and problems. This structural‐level stability supported our hypothesis that competence and problems tend to be inversely related and function together over time as integrated systems. We focus on one unexpected educational pathway characterized by individuals whose problems remain low over time despite stable levels of low competence. This unexpected educational pathway was examined further in terms of optimal versus general adjustment consequences in adulthood. Some policy implications of studying individual patterns and pathways are discussed.
Enemies to Allies: The Role of Policy‐Design Adaptation in Facilitating a Farmer–Environmentalist Alliance
Authors: Kash Jeffrey P.
Published: February 2008

In the period 1985 to 1996, agricultural conservation policy in the United States underwent a fundamental transition from a focus on policy design elements that emphasized short‐term economic returns for farmers and long‐term productivity to a focus on design elements that emphasized systemic environmental concerns. Although farmers' concerns with the environment were doubtlessly real, this adaptation of design elements allowed the agriculture policy community to gain the support of the environmental community for programs that offered new ways to channel short‐term economic support to farmers. The adaptation of design elements was triggered by the severe economic threat farmers began to experience in the late 1970s. This article investigates the language adaptations that facilitated the changes in agricultural conservation policy by analyzing the five policy‐design elements developed by Ingram and Schneider.
Assessing the Performance of Voluntary Environmental Programs: Does Certification Matter?
Authors: Darnall Nicole , Sides Stephen
Published: February 2008

The promotion of voluntary environmental programs (VEPs) as alternative approaches to traditional environmental regulation has fueled numerous researchers to evaluate VEP performance. However, these studies have focused on assessing the environmental performance of a single VEP. As yet, we know little about the overall environmental benefits of these programs. Moreover, questions remain about whether VEPs designed with different monitoring regimes—related to whether programs are self‐monitored or undergo external certification—vary in their ability to improve environmental conditions. Using meta‐analysis methodology, this article evaluates the aggregated environmental outcomes of U.S. VEPs drawing on data from nine studies and over 30,000 firms. We show that collectively VEP participants do not improve their environmental performance over nonparticipants. Rather, nonparticipants improve their environmental performance by 7.7 percent more than VEP participants. Additionally, nonparticipants improve the environment 24 percent more than participants in self‐monitored VEPs, whereas participants in International Standards Organization 14001as a groupexhibit inconclusive environmental performance improvements.
A Statistical Framework for Quantile Equivalence Clinical Trials with Application to Pharmacokinetic Studies that Bridge from HIV‐Infected Adults to Children
Authors: Pei Lixia , Hughes Michael D.
Published: February 2008

Summary Bridging clinical trials are sometimes designed to evaluate whether a proposed dose for use in one population, for example, children, gives similar pharmacokinetic (PK) levels, or has similar effects on a surrogate marker as an established effective dose used in another population, for example, adults. For HIV bridging trials, because of the increased risk of viral resistance to drugs at low PK levels, the goal is often to determine whether the doses used in different populations result in similar percentages of patients with low PK levels. For example, it may be desired to evaluate that a proposed pediatric dose gives approximately 10% of children with PK levels below the 10th percentile of PK levels for the established adult dose. However, the 10th percentile for the adult dose is often imprecisely estimated in studies of relatively small size. Little attention has been given to the statistical framework for such bridging studies. In this article, a formal framework for the design and analysis of quantile‐based bridging studies is proposed. The methodology is then developed for normally distributed outcome measures from both frequentist and Bayesian directions. Sample size and other design considerations are discussed.
Distinct Localization Patterns of Two Putative Mitochondrial Proteins in the Microsporidian Encephalitozoon cuniculi
Authors: WILLIAMS BRYONY A. P. , CALI ANN , TAKVORIAN PETER M. , KEELING PATRICK J.
Published: February 2008

ABSTRACT. Microsporidia were once considered amitochondriate, but have now been found to retain relict mitochondria called mitosomes. These organelles have been identified by immunolocalization in Trachipleistophora hominis, whereas most data on function have been inferred from the presence of mitochondrial protein‐encoding sequences in the genome of Encephalitozoon cuniculi. Here we describe the localization of two such enzymes in E. cuniculi cells. Immunofluorescent localization of ferredoxin involved in mitochondrial iron–sulfur cluster assembly reveals a punctate distribution as expected for mitochondria. In contrast, localization of mitochondrial glycerol‐3‐phosphate dehydrogenase suggests a cytoplasmic distribution in E. cuniculi and possible relocalization of this typically mitochondrial protein.
Factors governing the intranodal migration behavior of T lymphocytes
Authors: Worbs Tim , Bernhardt Günter , Förster Reinhold
Published: February 2008

Summary: With the advent of two‐photon microscopic imaging, the last few years have witnessed remarkable progress regarding our understanding of the movement behavior and interaction dynamics of different immune cells within lymphoid organs. The basal intranodal motility of naive T lymphocytes in the absence of antigenic or inflammatory stimuli, although at first glance representing a phenomenon of apparent simplicity, is far from being completely understood. The most important open question in this context relates to the origin of intranodal T‐cell motility itself: how are these highly dynamic cells ‘motivated’ to carry out their relentless scanning of dendritic cells present in the lymph node (LN)? This review summarizes recent advances in the search for factors governing the intranodal migration behavior of naive T lymphocytes, focusing in particular on the role of extracellular pro‐migratory cues, intracellular signaling components, and the influence of the structural LN environment on intranodal T‐cell motility.
Regulation of T‐cell migration and effector functions: insights from in vivo imaging studies
Authors: Pittet Mikael J. , Mempel Thorsten R.
Published: February 2008

Summary: Studies of the immune system are providing us with ever more detailed information on the cellular and molecular mechanisms that underlie our evolutionarily conserved ability to fend off infectious pathogens. Progress has probably been fastest at two levels: the various basic biological functions of isolated cells on one side and the significance of individual molecules or cells to the organism as a whole on the other. In both cases, direct phenomenological observation has been an invaluable methodological approach. Where we know least is the middle ground, i.e. how immune functions are integrated through the dynamic interplay of immune cell subsets within the organism. Most of our knowledge in this area has been obtained through inference from static snapshots of dynamic processes, such as histological sections, or from surrogate cell co‐culture models. The latter are employed under the assumption that an in vivo equivalent exists for each type of cellular contact artificially enforced in absence of anatomical compartmentalization. In this review, we summarize recent insights on migration and effector functions of T cells, focusing on observations gained from their dynamic microscopic visualization in physiological tissue environments.
Real‐time imaging of the cellular interactions underlying tolerance, priming, and responses to infection
Authors: Garside Paul , Brewer James M.
Published: February 2008

Summary: Much of what we understand about the anatomy and architecture of the immune system was revealed through exquisite experiments performed in the 1950s–1970s. These studies identified the role that anatomy played in a number of fundamental immunological phenomena including recirculation, induction of immune priming or tolerance, and the interactions of T and B cells. The recent resurgence of interest in the role of immune architecture and anatomy in basic immunological phenomena is almost entirely due to technological developments in identifying and tracking cells in vivo, not least through the ability to do this dynamically, in real time through the application of multiphoton microscopy. Here we outline the background to our own studies applying multiphoton microscopy to analysis of immune priming and tolerance, the role of adjuvants, T‐ and B‐cell interactions, and the application of these studies in infectious and inflammatory diseases. We then describe the impact that real time in vivo imaging has had on these areas. Finally, we engage in some ‘crystal ball gazing’ to look at what developments in imaging are likely to occur, why they are important, and what further information these approaches may distill regarding the development of the immune response.
Decoding the dynamics of T cell–dendritic cell interactions in vivo
Authors: Celli Susanna , Garcia Zacarias , Beuneu Hélène , Bousso Philippe
Published: February 2008

Summary: T lymphocytes receive activation signals during their encounters with antigen‐bearing dendritic cells (DCs) in secondary lymphoid organs. With the recent application of two‐photon imaging to visualize immune responses as they happen, the dynamics of T cell–DC interactions have been dissected in several mouse models. As we are integrating the results of these new studies, we are learning that the dynamics of T cell–DC interactions are regulated by multiple immunological parameters and, most importantly, that the spatiotemporal characteristics of these cell–cell contacts encode part of the T‐cell fate.
Two‐photon imaging of effector T‐cell behavior: lessons from a tumor model
Authors: Ng Lai Guan , Mrass Paulus , Kinjyo Ichiko , Reiner Steven L. , Weninger Wolfgang
Published: February 2008

Summary: Recent advances in two‐photon microscopy have provided a new way of visualizing the behavior of fluorescently tagged cells within their natural microenvironment. This technology has allowed for generating a detailed picture of the cellular interaction dynamics operant in the activation of T cells and B cells during primary immune responses within secondary lymphoid organs. In contrast, relatively little is known about the migratory and interactive behavior of effector T cells within peripheral organs. We have recently developed a two‐photon microscopy model that enables tracking of cytotoxic T cells within tumors. We have demonstrated that tumor‐infiltrating T lymphocytes (TILs) follow random migratory paths and that their migratory properties depend on signals from the T‐cell receptor. We further showed that TILs underwent short‐ and long‐term interactions with tumor cells as well as macrophages. Recently, we succeeded in dynamic imaging of the distribution of fluorescently tagged molecules within TILs at subcellular resolution, which will be instrumental for defining the composition of the lytic synapse as well as the targeted release of cytotoxic granules by these cells. The purpose of this review is to put our findings into the context of the current literature and to point out the molecular cues mediating effector T‐cell function as candidates for future investigation.
Epidemiology, clinical manifestations, and treatment options for skin and soft tissue infection caused by community‐acquired methicillin‐resistant Staphylococcus aureus
Authors: Farley Jason E.
Published: February 2008

Purpose: This article reviews the evolving epidemiology of community‐acquired methicillin‐resistant Staphylococcus aureus (CA‐MRSA) and the appropriate outpatient management of CA‐MRSA skin and soft tissue infection. Further, the paper will provide the basis upon which an individualized patient educational plan may be developed.

Data Sources: To complete this review, a search of English language publications was conducted through Medline and CINAHL databases (1966–2006).

Conclusions: The epidemiology of CA‐MRSA is becoming increasingly complex. Research that addresses the impact of this organism in high‐risk populations and within families is urgently needed.

Implications for Practice: Nurse practitioners must remain informed of the epidemiology of common and emerging drug‐resistant organisms in their patient populations.
Early structural adaptations to unloading in the human calf muscles
Authors: Seynnes O. R. , Maganaris C. N. , De Boer M. D. , Di Prampero P. E. , Narici M. V.
Published: February 2008

Aim:  The present study investigated the influence of muscle architectural changes on muscle torque during 3‐week unilateral lower limb suspension (ULLS).

Methods:  Plantarflexion maximal voluntary contraction (MVC), soleus (SOL), gastrocnemius medialis (GM) and lateralis (GL) muscle volume (VOL), GL fascicle length (Lf) and pennation angle (θ), physiological cross‐sectional area (PCSA), and electromyographic (EMG) activity were assessed in eight healthy men (aged 19 ± 0 years) after days 14 and 23 of ULLS.

Results:  After 14 day of ULLS, MVC and SOL EMG decreased (P < 0.05) by 10% and 29%, respectively, but did not further decline between days 14 and 23. SOL, GM and GL muscle VOL decreased by 5%, 6% and 5%, respectively (P < 0.05), on day 14, and by 7% (SOL), 10% (GM) and 6% (GL) on day 23. In GL, θ and Lf were reduced by 3% (P < 0.05) and 2% (NS), respectively, on day 14, and by 5% (P < 0.05) and 4% (P < 0.05), respectively, on day 23. Consequently, GL PCSA declined by 3% (P < 0.05) on day 14, but did not further decrease on day 23. Similarly, the 7% (P < 0.05) loss in GL force/PCSA observed on day 14 persisted until the end of the unloading period.

Conclusion:  These findings suggest that rapid muscle architecture remodelling occurs with lower limb unloading in humans, with changes occurring within 14 days of weight bearing removal. These adaptations, mitigating the decline in muscle PCSA, might protect from a larger loss of muscle force.
Major Topics of the Hadith
Authors: Lucas Scott C.
Published: February 2008

Hadiths – reports of what the Prophet Muhammad said, did, or tacitly approved – have exerted an extraordinary influence on Muslims for over a millennium. Despite the significance of this literature, its contents remain largely inaccessible to non‐Arabic readers, in part due to many Western scholars’ preoccupation with the question of its authenticity rather than the function of hadith in Islamic thought. This article provides an overview of the contents of the canonical Sunni hadith collections along with a sample of ethical hadiths in idiomatic English.
Cold Monsters and Ecological Leviathans: Reflections on the Relationships between States and the Environment
Authors: Whitehead Mark
Published: February 2008

The relationship between state administrations and environmental issues has been an enduring concern of geographers, environmentalists, philosophers, sociologists and political scientists for a considerable length of time. This article provides a critical review of approaches to the study of state–environment relations across of a range of different disciplines. While states have been criticised as either ineffectual, unjust, or even irrelevant managers of socio‐environmental relations in the modern world, this article argues that states continue to play a significant role within a range of environmental issues at a number of different scales. In order to explore the contested role of the state within contemporary environmental affairs, this article outlines three broad sets of approaches to state–environment relations: normative perspectives, critical approaches and notions of environmental governmentality. It is asserted that approaches adopting theories of environmental governmentality offer a critical, but highly creative, framework in and through which to study the contemporary entanglements of states and the environment.
‘Have You Seen Any Good Films Lately?’ Geopolitics, International Relations and Film
Authors: Dodds Klaus
Published: February 2008

This article explores the intersection between geopolitics, international relations and film. The first section examines how popular geopolitics and related areas of International Relations have engaged with film and Hollywood. Thereafter, it considers the interrelationship between Hollywood, the Bush administration and the post‐9/11 era in an attempt to better understand some of the contours of the military‐industrial‐media‐entertainment complex. At times of crisis, Hollywood has often been more than willing and able to produce and market films designed to ‘raise’ national morale and spirit. Finally, the article considers the challenge of researching audience reactions and the potential of a variety of sources, including interviews and online commentary to facilitate such discussions further.
The Pro‐oxidant Effects of Interactions of Ascorbate with Photoexcited Melanin Fade Away with Aging of the Retina†
Authors: Różanowski Bartosz , Burke Janice , Sarna Tadeusz , Różanowska Małgorzata
Published: February 2008

Photoexcited melanin from retinal pigment epithelium (RPE) has been shown to induce photo‐oxidation of ascorbate with concomitant generation of hydrogen peroxide. The aim of this study was to test whether the age‐related changes in melanin content and distribution in the RPE affect the susceptibility of RPE cells to ascorbate‐mediated photo‐oxidation. Our results demonstrate that there is an age‐dependent shift in the pathways with which ascorbate interacts in human RPE. In young RPE, melanin–ascorbate interactions may lead to pro‐oxidant effects, but in the aged there is no net increase in photo‐oxidation in the presence of ascorbate in comparison with samples without ascorbate. However, as ascorbate undergoes light‐induced depletion and photogenerates ascorbyl free radical in the old RPE cells with initial yields similar to that observed for young RPE, an influence of ascorbate on oxidation pathways is revealed in the old RPE as well. Interestingly, the pro‐oxidant effects of photoexcited melanolipofuscin–ascorbate interactions are greater than for photoexcited melanosomes when normalized to the same melanin content. The pro‐oxidant effects of photoexcited melanin–ascorbate interactions are strongly dependent on the irradiation wavelength, this being the greatest for the shortest wavelength studied (340 nm) and steeply decreasing with increasing wavelength but still detectable even at 600 nm.
Phytochemicals for Prevention of Solar Ultraviolet Radiation‐induced Damages†
Authors: Adhami Vaqar M. , Syed Deeba N. , Khan Naghma , Afaq Farrukh
Published: February 2008

While solar light is indispensable for sustenance of life, excessive exposure can cause several skin‐related disorders. The UV part of solar radiation, in particular, is linked to disorders ranging from mild inflammatory effects of the skin to as serious as causing several different types of cancers. Changes in lifestyle together with depletion in the atmospheric ozone layer during the last few decades have led to an increase in the incidence of skin cancer. Skin cancers consisting of basal and squamous cell carcinomas are especially linked to the UVB part of solar radiation. Reducing excessive exposure to solar radiation is desirable; however, as this approach is unavoidable, it is suggested that other novel strategies be developed to reduce the effects of solar radiation to skin. One approach to reduce the harmful effects of solar radiation is through the use of phytochemicals, an approach that is popularly known as “Photochemoprotection.” In recent years many phytochemicals with potential antioxidant properties have been identified and found to be photoprotective in nature. We describe here some of the most popular phytochemicals being studied that have the potential to reduce the harmful effects associated with solar UV radiation.
The oral mucosa: a model of wound healing with reduced scarring
Authors: Enoch S. , Moseley R. , Stephens P. , Thomas D.W.
Published: February 2008

This article reviews our understanding of the mechanisms involved in wound healing following injury. Models of preferential healing are described in the foetal skin, aged skin and the oral mucosa. The mechanisms underpinning the improved scarring observed in the oral mucosa are described and the role of resident fibroblasts, in mediating reduced scarring, is discussed.
Supersymmetry of the chiral de Rham complex
Authors: Ben-Zvi David , Heluani Reimundo , Szczesny Matthew
Published: February 2008

We present a superfield formulation of the chiral de Rham complex (CDR), as introduced by Malikov, Schechtman and Vaintrob in 1999, in the setting of a general smooth manifold, and use it to endow CDR with superconformal structures of geometric origin. Given a Riemannian metric, we construct an N=1 structure on CDR (action of the N=1 super-Virasoro, or Neveu–Schwarz, algebra). If the metric is Kähler, and the manifold Ricci-flat, this is augmented to an N=2 structure. Finally, if the manifold is hyperkähler, we obtain an N=4 structure. The superconformal structures are constructed directly from the Levi-Civita connection. These structures provide an analog for CDR of the extended supersymmetries of nonlinear σ-models.
Energy Management Techniques for Small- and Medium-Sized Companies (ESDA2006-95808)
Authors: Giacone Elena , Mancò Salvatore , Gabriele Pietro
Published: February 2008

Energy management in the industrial context is an important factor to attain energy savings as well as environmental efficiency. Often, linear regression models quite well represent the consumption of energy carriers and statistical process control (SPC) techniques, such as the cumulative sum (CUSUM) plot and Shewhart-like control charts, are currently applied to identify when a system changes the way energy is consumed. Despite the fact that SPC is widely applied in many fields, there is a lack of published material in energy management. The purpose of this paper is to widen the SPC techniques to be applied to energy management. Particular emphasis is given to small- and medium-sized enterprises since energy data are limited and generally known at system level. The CUSUM of the recursive residuals is proposed as the main tool for the analysis of energy consumption data, both for the historical and the monitoring phases. In addition, tabular CUSUM and EWMA control charts are also included.
The Physics of Bird Flight: An Experiment
Authors: Mihail Michael D. , George Thomas F. , Feldman Bernard J.
Published: February 2008

This article describes an experiment that measures the forces acting on a flying bird during takeoff. The experiment uses a minimum of equipment and only an elementary knowledge of kinematics and Newton's second law. The experiment involves first digitally videotaping a bird during takeoff, analyzing the video to determine the bird's position as a function of time and its flapping rate, calculating the velocity of the bird's wings, and finally, inserting those results into Newton's second law of physics. The experiment has been designed for a high school physics class. This article is a follow-up on our recently published theoretical article on the origin of bird flight.1
Direct and Indirect Effects of Resource Quality on Food Web Structure
Authors: Bukovinszky Tibor , van Veen F. J. Frank , Jongema Yde , Dicke Marcel
Published: February 2008

The diversity and complexity of food webs (the networks of feeding relationships within an ecological community) are considered to be important factors determining ecosystem function and stability. However, the biological processes driving these factors are poorly understood. Resource quality affects species interactions by limiting energy transfer to consumers and their predators, affecting life history and morphological traits. We show that differences in plant traits affect the structure of an entire food web through a series of direct and indirect effects. Three trophic levels of consumers were influenced by plant quality, as shown by quantitative herbivore–parasitoid–secondary parasitoid food webs. We conclude, on the basis of our data, that changes in the food web are dependent on both trait- and density-mediated interactions among species.
Reciprocal Binding of PARP-1 and Histone H1 at Promoters Specifies Transcriptional Outcomes
Authors: Krishnakumar Raga , Gamble Matthew J. , Frizzell Kristine M. , Berrocal Jhoanna G. , Kininis Miltiadis , Kraus W. Lee
Published: February 2008

Nucleosome-binding proteins act to modulate the promoter chromatin architecture and transcription of target genes. We used genomic and gene-specific approaches to show that two such factors, histone H1 and poly(ADP-ribose) polymerase-1 (PARP-1), exhibit a reciprocal pattern of chromatin binding at many RNA polymerase II–transcribed promoters. PARP-1 was enriched and H1 was depleted at these promoters. This pattern of binding was associated with actively transcribed genes. Furthermore, we showed that PARP-1 acts to exclude H1 from a subset of PARP-1–stimulated promoters, suggesting a functional interplay between PARP-1 and H1 at the level of nucleosome binding. Thus, although H1 and PARP-1 have similar nucleosome-binding properties and effects on chromatin structure in vitro, they have distinct roles in determining gene expression outcomes in vivo.
Quantum Phase Extraction in Isospectral Electronic Nanostructures
Authors: Moon Christopher R. , Mattos Laila S. , Foster Brian K. , Zeltzer Gabriel , Ko Wonhee , Manoharan Hari C.
Published: February 2008

Quantum phase is not directly observable and is usually determined by interferometric methods. We present a method to map complete electron wave functions, including internal quantum phase information, from measured single-state probability densities. We harness the mathematical discovery of drum-like manifolds bearing different shapes but identical resonances, and construct quantum isospectral nanostructures with matching electronic structure but divergent physical structure. Quantum measurement (scanning tunneling microscopy) of these “quantum drums”—degenerate two-dimensional electron states on the copper(111) surface confined by individually positioned carbon monoxide molecules—reveals that isospectrality provides an extra topological degree of freedom enabling robust quantum state transplantation and phase extraction.
Repression of the Transcription Factor Th-POK by Runx Complexes in Cytotoxic T Cell Development
Authors: Setoguchi Ruka , Tachibana Masashi , Naoe Yoshinori , Muroi Sawako , Akiyama Kaori , Tezuka Chieko , Okuda Tsukasa , Taniuchi Ichiro
Published: February 2008

Mouse CD4
+
CD8
+
double-positive (DP) thymocytes differentiate into CD4
+
helper-lineage cells upon expression of the transcription factor Th-POK but commit to the CD8
+
cytotoxic lineage in its absence. We report the redirected differentiation of class I–restricted thymocytes into CD4
+
CD8
–
helper-like T cells upon loss of Runx transcription factor complexes. A Runx-binding sequence within the
Th-POK
locus acts as a transcriptional silencer that is essential for
Th-POK
repression and for development of CD8
+
T cells. Thus, Th-POK expression and genetic programming for T helper cell development are actively inhibited by Runx-dependent silencer activity, allowing for cytotoxic T cell differentiation. Identification of the transcription factors network in CD4 and CD8 lineage choice provides insight into how distinct T cell subsets are developed for regulating the adaptive immune system.
Independent Loss of Immunogenic Proteins in
Mycobacterium ulcerans
Suggests Immune Evasion
Authors: Huber Charlotte A. , Ruf Marie-Thérèse , Pluschke Gerd , Käser Michael
Published: February 2008

The highly immunogenic mycobacterial proteins ESAT-6, CFP-10, and HspX represent potential target antigens for the development of subunit vaccines and immunodiagnostic tests. Recently, the complete genome sequence revealed the absence of these coding sequences in
Mycobacterium ulcerans
, the causative agent of the emerging human disease Buruli ulcer. Genome reduction and the acquisition of a cytopathic and immunosuppressive macrolide toxin plasmid are regarded as crucial for the emergence of this pathogen from its environmental progenitor,
Mycobacterium marinum
. Earlier, we have shown the evolution of
M. ulcerans
into two distinct lineages. Here, we show that while the genome of
M. marinum
M contains two copies of the
esxB-esxA
gene cluster at different loci (designated MURD4 and MURD152), both copies are deleted from the genome of
M. ulcerans
strains belonging to the classical lineage. Members of the ancestral lineage instead retained some but disrupted most functional MURD4 or MURD152 copies, either by newly identified genomic insertion-deletion events or by conversions of functional genes to pseudogenes via point mutations. Thus, the
esxA
(ESAT-6),
esxB
(CFP-10), and
hspX
genes are located in hot-spot regions for genomic variation where functional disruption seems to be favored by selection pressure. Our detailed genomic analyses have identified a variety of independent genomic changes that have led to the loss of expression of functional ESAT-6, CFP-10, and HspX proteins. Loss of these immunodominant proteins helps the bacteria bypass the host's immunological response and may represent part of an ongoing adaptation of
M. ulcerans
to survival in host environments that are screened by immunological defense mechanisms.
Prophages in
Listeria monocytogenes
Contain Single-Nucleotide Polymorphisms That Differentiate Outbreak Clones within Epidemic Clones
Authors: Chen Yi , Knabel Stephen J.
Published: February 2008

A fragment end ligation-mediated PCR strategy was used to analyze the AscI pulsed-field gel electrophoresis patterns of
Listeria monocytogenes
epidemic clone II (ECII), which led to the identification of single-nucleotide polymorphisms (SNPs) in prophage regions that differentiated the two ECII outbreak clones. SNPs in prophages that differentiated the outbreak clones of ECIII and -IV were also identified.
Comparison of Nine Commercially Available Assays for Quantification of Antibody Response to Hepatitis B Virus Surface Antigen
Authors: Huzly D. , Schenk T. , Jilg W. , Neumann-Haefelin D.
Published: February 2008

Quantitative measurement of anti-HBs is used to evaluate the response to hepatitis B vaccination in health care workers and to optimize postexposure management. The different guidelines for hepatitis B vaccination and booster policy imply that the measurement of anti-HBs levels by different assays is accurate and consistent, yielding comparable quantitative results. We measured anti-HBs levels in 200 serum samples from patients and health care professionals by nine different anti-HBs assays and compared the quantitative results and the performance characteristics of the different test systems. The assay specificity ranged between 96.8 and 100% when sera from individuals without a vaccination history and with negative anti-HBc status were defined as true negatives. Sensitivity ranged between 93.5 and 100%. A high number of sera showed discrepancies between measurements by the different systems. The mean coefficient of variation between the different measurements was 47.1% (range, 15.0 to 201.0%), and the factors of multiplication ranged from 2.8 to 105. Hemolysis or lipemia did not seem to influence the measurement, and there was no difference between anti-HBc-positive and -negative individuals. The classical enzyme immunoassays tend to find lower anti-HBs levels than the automated systems, with higher values by the Abbott AXSYM assay. The serial dilution of the international standard preparation was measured accurately by most of the assays. In conclusion, the quantitative measurement of anti-HBs levels is not reliable, even though an international standard is used for the calibration of the systems. Some systems showed specific problems that should be addressed by the manufacturers.