bluuebunny/crossref_metadata_2025 huggingface dataset:
User experience design and agile development: managing cooperation through articulation work
Authors: Ferreira Jennifer , Sharp Helen , Robinson Hugh
Published: July 2011

Previous discussions of how User Experience (UX) designers and Agile developers can work together have focused on bringing the disciplines together by merging their processes or adopting specific techniques. This paper reports in detail on one observational study of a mature Scrum team in a large organization, and their interactions with the UX designers working on the same project. The evidence from our study shows that Agile development and UX design practice is not explained by rationalized accounts dealing with processes or techniques. Instead, understanding practice requires examining the wider organizational setting in which the Agile developers and UX designers are embedded. Our account focuses on the situatedness of the work by making reference to values and assumptions in the organizational setting, and the consequences that those values and assumptions had for practice. In this organizational setting, cooperation between the Agile developers and UX designers was achieved through ongoing articulation work by the developers, who were compelled to engage a culturally distinct UX design division. Based on this study, insights into culture, self‐organization and purposeful work highlight significant implications for practice. Copyright © 2011 John Wiley & Sons, Ltd.
Inverse link between density and dispersal distance in butterflies: field evidence from six co‐occurring species
Authors: Konvicka Martin , Zimmermann Kamil , Klimova Martina , Hula Vladimir , Fric Zdenek
Published: July 2011

A pertinent question in animal population ecology is the relationship between population abundance, density, and mobility. Two extreme ways to reach sufficient abundance for long‐term persistence are to inhabit restricted locations at high densities, or large areas in low densities. The former case predicts low individual mobility, whereas the later predicts high one. This assumption is rarely tested using across‐species comparisons, due to scarcity of data on both mobility and population sizes for multiple species. We used data on dispersal and local population densities of six butterfly species gained by mark‐recapture, and data on their (relative) regional abundance obtained by walking transects in a landscape surrounding the mark‐recapture sites. We correlated both local density and regional abundance against slopes of the inverse power function, appropriate for describing the shape of dispersal kernel. Local densities correlated negatively with the dispersal kernel slopes both when sexes were treated as independent data points and if treated together. For regional abundance, the correlation was also negative but only marginally significant. Our results corroborate the notion that a trade‐off exists between living in dense populations and having poor dispersal, and vice versa. We link this observation to resource use by individual species, and distribution of such resources as host plants in the study landscape.
Indirect effects of excessive deer browsing through understory vegetation on stream insect assemblages
Authors: Sakai Masaru , Natuhara Yosihiro , Imanishi Ayumi , Imai Kensuke , Kato Makoto
Published: July 2011

Over the past decade, the abundance of sika deer has rapidly increased around Japan. Previous studies have showed overabundance of deer causes drastic reduction of forest understory vegetation, leading excessive soil erosion. However, no study has investigated the effects of excessive deer browsing on aquatic insect assemblages via sediment runoff. These effects are important to understand whether the terrestrial alteration by deer influences aquatic ecosystems. In a primary deciduous forest catchment in Ashiu, Kyoto, a deer exclusion fence has been in place since 2006. We compared forest floor cover, overland flow, stream environment, and aquatic insect assemblages in first‐order streams and catchments inside and outside of the deer‐exclosure from May‐2008 to April‐2009. The floor inside the deer‐exclosure catchment was covered by lush understory vegetation, whereas outside was almost bare. The overland flow runoff rate at midslope and the dominancy of fine sediment deposition in the streambed were higher outside than inside. Among aquatic insects, burrowers, which are tolerant against fine sediment deposition, were significantly more abundant outside than inside, whereas clingers exhibited the opposite patterns. Collector‐gatherers, which feed on fine detritus, were significantly more abundant outside than inside. Meanwhile, filterers were more abundant inside. The Simpson's diversity index of the aquatic insect assemblages was higher inside than outside. These results suggest that the demise of understory vegetation due to excessive deer browsing has indirectly caused changes in the aquatic insect assemblages of this catchment via increased sediment runoff and subsequent sandy sedimentation of the streambed.
Plantlet recruitment is the key demographic transition in invasion byKalanchoe daigremontiana
Authors: Herrera Ileana , Hernandez Maria‐Josefina , Lampo Margarita , Nassar Jafet M.
Published: July 2011

Biological invasions have a great impact on biodiversity and ecosystem functioning worldwide.Kalanchoe daigremontianais a noxious invasive plant in arid zones. Besides being toxic for domestic animals and wildlife, this species inhibits the growth of native plants. Its rapid proliferation in Cerro Saroche National Park (Venezuela) is of great concern because this area hosts several species endemic to the scarce arid zones in the Caribbean. The traits ofK. daigremontianathat contribute to its invasive success are unknown. Based on empirical data, we derived a stage structured, stochastic and density‐dependent model, to identify characteristics relevant for its establishment. Sensitivity analyses revealed that the establishment ofK. daigremontianadepends exclusively on plantlet recruitment. Because asexual plantlets reproduce in less than 1 year populations are able to increase rapidly during the initial phases of invasion, when extinction risks are higher. Sexual seedlings, on the contrary, require a minimum of 3 years to reproduce. As a result, seedling recruitment contributes little to the transient dynamics of the population and therefore cannot warrant the successful establishment of the species. Simulations of various management strategies show that eradication through plant removal may only be achieved if harvest begins shortly after introduction. If a rapid response is not possible, reducing the survival and growth rates of plantlets through biological control is an alternative option. Thus, a strict control of dispersal of plantlets by humans and a continuous monitoring of new invasions should be the first priority for reducing further impact on native species.
Bioconversion of ovine scotta into lactic acid with pure and mixed cultures of lactic acid bacteria
Authors: Secchi Nicola , Giunta Daniela , Pretti Luca , García Mónica Ruiz , Roggio Tonina , Mannazzu Ilaria , Catzeddu Pasquale
Published: July 2011

Scotta is the main by-product in the making of ricotta cheese. It is widely produced in southern Europe and particularly in Italy where it represents a serious environmental pollutant due to its high lactose content. With the aim of evaluating whether scotta bioconversion into lactic acid can be considered as an alternative to its disposal, besides providing it with an added value, here the growth, fermentative performances, and lactic acid productions of pure and mixed cultures of Lactobacillus casei, Lactobacillus helveticus, and Streptococcus thermophilus were evaluated on ovine scotta-based media, without and with the addition of nutritional supplements. The outcomes indicate that ovine scotta can be utilized for the biotechnological production of lactic acid with yields up to 92%, comparable to those obtained on cheese-whey. Indeed, the addition of nutritional supplements generally improves the fermentative performances of lactic acid bacteria leading to about 2 g l−1 h−1 of lactic acid. Moreover, the use of mixed cultures for scotta bioconversion reduces the need for nutritional supplements, with no detrimental effects on the productive parameters compared to pure cultures. Finally, by using L. casei and S. thermophilus in pure and mixed cultures, up to 99% optically pure l-lactic acid can be obtained.
Effects of physical culture parameters on bacteriocin production by Mexican strains of Bacillus thuringiensis after cellular induction
Authors: Martínez-Cardeñas Janeth Adriana , de la Fuente-Salcido Norma M , Salcedo-Hernández Rubén , Bideshi Dennis K , Barboza-Corona J Eleazar
Published: July 2011

We have shown previously that in the presence of inducer Bacillus cereus 183, significant increases in bacteriocin production and bactericidal activity of B. thuringiensis occur when the latter is cultivated at pH 7.2, 28°C, and 180 rpm. Here we show that this activity can be further improved when B. thuringiensis is induced with B. cereus 183 and then cultivated with modification of pH, temperature, and agitation. Five native strains of B. thuringiensis, LBIT 269, LBIT 287, LBIT 404, LBIT 420, and LBIT 524 which synthesize, respectively, morricin 269, kurstacin 287, kenyacin 404, entomocin 420, and tolworthcin 524, were cultivated in four different fermentation media. Of these, fermentation in tryptic soy broth (TSB) yielded the highest level of bacteriocin activity (~100–133 FU). Bacteria grown in TSB were induced with B. cereus 183 and cultivated at different pH (6.0, 7.2, 8.0), temperature (26, 28, 30°C), and agitation (150, 180, 210 rpm). Full factorial design was performed and results were analyzed with analysis of variance (ANOVA) and Tukey multiple comparison tests at significant level of α ≤ 0.05 to study the influence of the three variables on bacterial growth and bacteriocin production. Our data show that the highest bacteriocin activity was found with LBIT 269 and LBIT 404 with an increase of ~95–100% compared with induced B. thuringiensis strains cultivated under fixed conditions (pH 7.2, 28°C, 180 rpm), for which the data were set at 0%. The optimal conditions for morricin 269 and kenyacin 404 production were, respectively, pH 8, 30°C, 210 rpm and pH 7.2, 26°C, 210 rpm.
Polyunsaturated Fatty Acid Concentrates of Carp Oil: Chemical Hydrolysis and Urea Complexation
Authors: Crexi Valéria T. , Monte Micheli L. , Monte Maurício L. , Pinto Luiz A. A.
Published: July 2011

The aims of this study were to compare three treatments in the chemical hydrolysis reaction of bleached oil from carp (Cyprinus carpio) heads and to obtain polyunsaturated fatty acid concentrates by urea complexation. The three treatments were carried out with different oil:ethanol molar ratios. In the treatment with a 1:39 molar ratio, a higher yield of free fatty acids was found. These fatty acids were submitted to urea complexation (−10 °C for 20 h, and urea–fatty acid ratio of 4.5–1). There was a 31.4% increase in monounsaturated and polyunsaturated fatty acids (MUFA and PUFA) content and a 75% decrease in saturated fatty acids (SAF) content. An increase of 85.4% in the EPA + DHA content was found. The non‐urea complexing fraction can be considered a rich source of MUFA and PUFA with a total amount of 88.9%.
Role of DNA methylation in head and neck cancer
Authors: Demokan Semra , Dalay Nejat
Published: July 2011

Head and neck cancer (HNC) is a heterogenous and complex entity including diverse anatomical sites and a variety of tumor types displaying unique characteristics and different etilogies. Both environmental and genetic factors play a role in the development of the disease, but the underlying mechanism is still far from clear. Previous studies suggest that alterations in the genes acting in cellular signal pathways may contribute to head and neck carcinogenesis. In cancer, DNA methylation patterns display specific aberrations even in the early and precancerous stages and may confer susceptibility to further genetic or epigenetic changes. Silencing of the genes by hypermethylation or induction of oncogenes by promoter hypomethylation are frequent mechanisms in different types of cancer and achieve increasing diagnostic and therapeutic importance since the changes are reversible. Therefore, methylation analysis may provide promising clinical applications, including the development of new biomarkers and prediction of the therapeutic response or prognosis. In this review, we aimed to analyze the available information indicating a role for the epigenetic changes in HNC.
The Strength and Difficulties Questionnaire: Russian validation of the teacher version and comparison of teacher and student reports
Authors: Ruchkin Vladislav , Koposov Roman , Vermeiren Robert , Schwab‐Stone Mary
Published: July 2011

Objective

To confirm factor structure of the teacher Strengths and Difficulties Questionnaire (SDQ) and to compare teacher and student reports in Russian youth.

Method

The SDQ and psychopathology measures were completed by teachers in a representative sample of urban adolescents (N = 528). The factor structure was examined on two randomly selected split‐halves of the sample, and using a gender split. The functional impairment score was predicted by the SDQ problem scales.

Results

The fit for all models was acceptable. The fit did not decrease when applying increasing constraints in the random‐split model, but became significantly worse for the gender model, suggesting lack of measure invariance. SDQ problem scales explained 37% of functional impairment variance. Significant scale interaction (emotional problems∗peer problems and conduct problems∗hyperactivity) suggest that combination of these problems produces an additional impact on functioning.

Conclusions

The SDQ teacher report may represent a potentially useful screener for children and youth.
Spontaneous C‐cleavage of a mini‐intein without its conserved N‐terminal motif A
Authors: Qi Xingmei , Meng Qing , Liu Xiang-Qin
Published: July 2011

Previously, the C‐terminal fragment of a split intein was known to undergo controllable C‐cleavage at its C‐terminus only when the N‐terminal fragment of the intein was added. Here we constructed a similar split intein from the Ssp DnaX intein, but we unexpectedly observed that its C‐terminal 136‐aa fragment could undergo spontaneous C‐cleavage without the N‐terminal fragment that was up to 15 aa long and contained the conserved intein motif A. This C‐cleavage activity was significantly decreased by a mutation of the conserved Thr residue in the conserved intein motif B. These findings suggest a robust intein structure in the absence of motif A and a larger role of motif B in the third step of the protein splicing mechanism.
Effect of repeated restraint stress and clomipramine on Na+/K+‐ATPase activity and behavior in rats
Authors: Balk Rodrigo de Souza , Silva Michele Hinerasky da , Bridi Jessika Cristina , Carvalho Nelson Rodrigues , Portella Rafael de Lima , Dobrachinski Fernando , Amaral Guilherme Pires , Barcelos Rômulo , Dias Glaecir Roseni Mundstock , Rocha João Batista Teixeira da , Barbosa Nilda Berenice Vargas , Soares Felix Alexandre Antunes
Published: July 2011

Activation of the limbic‐hypothalamic‐pituitary‐adrenal axis (LHPA) and the release of glucocorticoids are fundamental for the adaptive response and immediate survival of an organism in reaction to acute stimuli. However, high levels of glucocorticoids in the brain may produce neuronal injury and a decrease of Na+/K+‐ATPase activity, with effects on neurotransmitter signaling, neural activity, as well as the whole animal behavior. Clomipramine is a tricyclic antidepressant that inhibits the reuptake of serotonin and norepinephrine by indirect actions on the dopaminergic system and LHPA axis. Its chronic use increases the body's ability to cope with stress; however, high doses can potentiate its side effects on memory, learning, and sensory motor function. The purpose of the present study was to compare the effect of repeated restraint stress and clomipramine treatment on Na+/K+‐ATPase activity and on the behavior of male rats. Changes in the behavioral response were evaluated by measuring the memory, learning, anxiety, and exploratory responses. Our results showed that exposure to repeated restraint stress reduced levels of Na+/K+‐ATPase in brain structures and changed short and long‐term memory, learning, and exploratory response when compared to the control group. Exposure to clomipramine treatment increased anxiety levels and reduced Na+/K+‐ATPase activity in the cerebral cortex as well as short term memory, learning, and exploratory response. In conclusion, the present results provide additional evidence concerning how repeated restraint stress and clomipramine chronically administered at higher dose levels affect the neural activity and behavior of male rats.
Product safety and security in the global supply chain: Issues, challenges and research opportunities
Authors: Marucheck Ann , Greis Noel , Mena Carlos , Cai Linning
Published: July 2011

A number of high profile product safety events and recalls have heightened public attention to the safety and security of the products that people consume and use. While product safety isn’t a new topic, the effect of the global supply chain in creating or exacerbating safety risks and vulnerabilities is both timely and relevant. In this essay we focus on how the field of operations management can provide fresh perspectives and insights in addressing the challenges of product safety and security in the global supply chain. We first examine the product safety issues and challenges that arise in five industries that are increasingly globalizing their supply chains: food, pharmaceuticals, medical devices, consumer products and automobiles. We describe four areas where operations management theory and methodologies can provide fresh insights and innovative solutions in addressing these problems; regulation and standards, product lifecycle management, traceability and recall management, and supplier relationships.
Gesundheitsförderung für Un- und Angelernte: ReSuM
Authors: Busch Christine , Ducki Antje
Published: July 2011

Einleitung

Gesundheitsförderung für Un- und Angelernte ist angesichts der sozial ungleich verteilten Gesundheitschancen dringend erforderlich. Allerdings ist der Zugang zu dieser Zielgruppe schwierig. ReSuM ist ein wissenschaftlich fundiertes und evaluiertes Programm für Beschäftigte in un- und angelernten Tätigkeiten, das von Präventionsanbietern routinemäßig eingesetzt werden kann. Ein detailliertes Programmmanual ist veröffentlicht.
Exchange flow of two immiscible fluids and the principle of maximum flux
Authors: KERSWELL R. R.
Published: July 2011

The steady, coaxial flow in which two immiscible, incompressible fluids of differing densities move past each other slowly in a vertical cylindrical tube has a continuum of possibilities due to the arbitrariness of the interface between the fluids. By invoking the presence of surface tension to at least restrict the shape of any interface to that of a circular arc or full circle, we consider the following question: which flow will maximise the exchange when there is only one dividing interface Γ? Surprisingly, the answer differs fundamentally from the better-known co-directional two-phase flow situation where an axisymmetric (concentric) core-annular solution always optimises the flux. Instead, the maximal flux state is invariably asymmetric either being a ‘side-by-side’ configuration where Γ starts and finishes at the tube wall or aneccentriccore-annular flow where Γ is an off-centre full circle in which the more viscous fluid is surrounded by the less viscous fluid. The side-by-side solution is the most efficient exchanger for a small viscosity ratio β ≲ 4.60 with an eccentric core-annular solution optimal otherwise. At large β, this eccentric solution provides 51% more flux than the axisymmetric core-annular flow which is always a local minimiser of the flux.
Excitation of steady and unsteady Görtler vortices by free-stream vortical disturbances
Authors: WU XUESONG , ZHAO DIFEI , LUO JISHENG
Published: July 2011

Excitation of Görtler vortices in a boundary layer over a concave wall by free-stream vortical disturbances is studied theoretically and numerically. Attention is focused on disturbances with long streamwise wavelengths, to which the boundary layer is most receptive. The appropriate initial-boundary-value problem describing both the receptivity process and the development of the induced perturbation is formulated for the generic case where the Görtler number GΛ (based on the spanwise wavelength Λ of the disturbance) is of order one. The impact of free-stream disturbances on the boundary layer is accounted for by the far-field boundary condition and the initial condition near the leading edge, both of which turn out to be the same as those given by Leib, Wundrow & Goldstein (J. Fluid Mech., vol. 380, 1999, p. 169) for the flat-plate boundary layer. Numerical solutions show that for a sufficiently small GΛ, the induced perturbation exhibits essentially the same characteristics as streaks occurring in the flat-plate case: it undergoes considerable amplification and then decays. However, when GΛ exceeds a critical value, the induced perturbation exhibits (quasi-) exponential growth. The perturbation acquires the modal shape of Görtler vortices rather quickly, and its growth rate approaches that predicted by local instability theories farther downstream, indicating that Görtler vortices are excited. The amplitude of the Görtler vortices excited is found to decrease as the frequency increases, with steady vortices being dominant. Comprehensive quantitative comparisons with experiments show that the eigenvalue approach predicts the modal shape adequately, but only the initial-value approach can accurately predict the entire evolution of the amplitude. An asymptotic analysis is performed for GΛ ≫ 1 to map out distinct regimes through which a perturbation with a fixed spanwise wavelength evolves. The centrifugal force starts to influence the generation of the pressure when x* ~ ΛRΛG−2/3Λ, where RΛ denotes the Reynolds number based on Λ. The induced pressure leads to full coupling of the momentum equations when x* ~ ΛRΛGΛ−2/5. This is the crucial regime linking the pre-modal and modal phases of the perturbation because the governing equations admit growing asymptotic eigensolutions, which develop into fully fledged Görtler vortices of inviscid nature when x* ~ ΛRΛ. From this position onwards, local eigenvalue formulations are mathematically justified. Görtler vortices continue to amplify and enter the so-called most unstable regime when x* ~ ΛRΛGΛ, and ultimately approach the right-branch regime when x* ~ ΛRΛG2Λ.
ECONOMIC ANALYSIS OF CEREAL, VEGETABLE AND GRAPE PRODUCTION SYSTEMS IN URBAN AND PERI-URBAN AGRICULTURE OF KABUL, AFGHANISTAN
Authors: SAFI ZIKRULLAH , DOSSA LUC HIPPOLYTE , BUERKERT ANDREAS
Published: July 2011

Little is known about the economics of urban and peri-urban agriculture in Kabul, Afghanistan. This study therefore aimed to investigate the profitability of 15 mixed cropping farms with a total of 42 farm plots that were selected from a survey of 100 households (HHs). The sample represented the three dominant farm types: cereal producers (15 plots), vegetable farmers (15 plots) and grape producers (12 plots). A cost-revenue analysis of all inputs and outputs (costs of tillage, seed where applicable, weeding, harvesting, casual labour, machinery use, pruning, pesticides and of revenue from produce sold) over two years showed major differences in net HH income. Differences were largely due to production type and crops grown and reflected differences in market prices for produce. Cereal production yielded a total bi-annual revenue of 9630 US$ ha−1, and a gross margin and a net profit of 8770 US$ ha−1. Vegetable farming gave an average bi-annual revenue of 27 900 US$ ha−1, a gross margin of 26 330 US$ ha−1and a net profit of 25 530 US$ ha−1. Surprisingly, vineyards generated the lowest returns with a revenue of 5400 US$ ha−1, and a gross margin and a net profit of 4480 US$ ha−1. The results suggest that among the production systems studied vegetable cultivation was most profitable given its direct linkage to city market demands, rather stable prices and much shorter growing season than for cereals and grapes. In addition, the inflow of wheat and grapes from rural areas into the city negatively affects local producer revenues. If vineyards are to be maintained in the city surroundings, incentives such as subsidized credit may need to be made available to producers.
‘One cannot help liking them’: Terra Nova meets Fram
Authors: Hooper Meredith
Published: July 2011

During January 1911 two separate expeditions came ashore within ten days of each other in Antarctica. Both were hoping to achieve the South Pole. Robert Falcon Scott's decision to establish his British Antarctic Expedition's winter quarters on Ross Island close to routes explored on his first Antarctic expedition was signalled in advance. Scott had received notification of the Norwegian Roald Amundsen's intention to head for Antarctica but did not know where he planned to land. At 00.05 am on 4 February 1911 the British expedition's vessel Terra Nova unexpectedly came across Amundsen's Fram moored to the ice edge in the Bay of Whales. 14 hours later Terra Nova departed, taking news of Amundsen's location and plans, to deliver to Scott. For those on Terra Nova who kept diaries, the event filled days surrounding the encounter spurred the recording of thoughts, emotions and conversations as well as descriptions: eye witness accounts, allowing us to gain an appreciation of the situation as it was. This material from the British side, together with letters, and diary entries from earlier in the voyage, reveals a more complex account than do expedition narratives published subsequently by several of the participants. Terra Nova's passage along the edge of the Ross Ice Shelf in February 1911 had, in fact, come close to being cancelled. Terra Nova's commander as instructed by Scott was heading for Balloon Bight on 3 February, not the Bay of Whales. Even the ship's departure after a short stay, with everyone still on board, became a matter for intense debate. In addition, the generally very positive attitude of the British towards the Norwegians as expressed in diaries hardened subsequently, at least for some. This paper's focus is on the responses of those on Terra Nova to the encounter. Those of the Norwegians are being explored by other researchers.
The present and future competence of the European Union in the Arctic
Authors: Koivurova Timo , Kokko Kai , Duyck Sebastien , Sellheim Nikolas , Stepien Adam
Published: July 2011

The European Union's (EU's) intention of becoming a permanent observer in the Arctic Council and the reluctance of Arctic actors to grant it that status have made the union's aspirations in the Arctic the subject of a continuing debate. The discussion appears to be dominated by geographical considerations and the EU's gradually emerging Arctic policy. This article puts forward a different view of the EU's presence in the region, one drawing on an analysis of relevant EU competences. As a complex international actor, the EU has acquired a broad array of decision-making powers from its member states, powers that partly extend to Iceland and Norway via the EEA Agreement. Moreover, the EU has in many cases become a relevant actor in international negotiations and treaty making processes the outcomes of which are of crucial importance for the governance of the Arctic. Our argument in the third and concluding section is that only by including the EU in Arctic governance can the international community provide better prospects for the union to sensitise its policies and discourses to the Arctic realities and for other Arctic actors to understand how the union functions. This argument is supported by an analysis of the EU's restrictions on the import of seal products and the ensuing litigation.
CO2 and Pourquoi-Pas?
Authors: Baker F.W.G.
Published: July 2011

During the explorations of Pourquoi-Pas?, commanded by Jean Baptiste Charcot, in the Southern Ocean in the period 1908–1910, Ensign R.-E. Godfroy collected, between latitudes 64°09'S and 70°05'S, eleven samples of air, according to instructions given by Muntz and Luné (1911) for measuring the concentrations of CO2 in the atmosphere. The samples were later analysed in the laboratories of the Conservatoire des Arts et Metiers, Paris using basically the same methods as for the samples collected by the French First Polar Year expedition 1882–1883 (Baker 2009). The maximum concentration of CO2 was 255 ppm, the minimum 145 ppm (the sample taken at sea at 69°30'S) and the mean 205 ppm. The average of the concentrations in the samples made by the French first IPY expedition at Bahia Orange was 256ppm and the minimum was 231 ppm.
Poor school performance in offspring of patients with schizophrenia: what are the mechanisms?
Authors: Jundong J. , Kuja-Halkola R. , Hultman C. , Långström N. , D'Onofrio B. M. , Lichtenstein Paul
Published: July 2011

Background

Offspring of patients with schizophrenia exhibit poorer school performance compared with offspring of non-schizophrenic parents. We aimed to elucidate the mechanisms behind this association.

Method

We linked longitudinal national population registers in Sweden and compared school performance among offspring of schizophrenic parents with offspring of non-schizophrenic parents (1 439 215 individuals with final grades from compulsory school 1988–2006). To investigate the mechanisms, we studied offspring of schizophrenic patients and controls within the same extended families. We investigated genetic effects by stratifying analyses of parent–child associations according to genetic relatedness (half-cousins, full cousins and half-siblings). Environmental effects were investigated by comparing school performance of offspring of schizophrenic fathers and of schizophrenic mothers, respectively, and by stratifying the analyses according to environmental relatedness while controlling genetic relatedness (paternal and maternal half-cousins, paternal and maternal half-siblings).

Results

Offspring of parents with schizophrenia had poorer overall school performance than unrelated offspring of non-schizophrenic parents (−0.31s.d.). Variability in genetic relatedness greatly moderated the strength of the within-family association (β=−0.23 within exposure-discordant half-cousins, β=−0.13 within exposure-discordant full cousins, β=0.04 within exposure-discordant half-siblings), while no evidence was found that the environment affected offspring school performance.

Conclusions

Genetic factors account for poorer school performance in children of parents with schizophrenia. This supports that cognitive deficits found in individuals with schizophrenia and their relatives might be genetically inherited. Early detection of prodromal signs and impaired functioning of offspring of patients with schizophrenia could lead to earlier and better tailored interventions.
Self-monitoring as a familial vulnerability marker for psychosis: an analysis of patients, unaffected siblings and healthy controls
Authors: Hommes J. , Krabbendam L. , Versmissen D. , Kircher T. , van Os J. , van Winkel R.
Published: July 2011

Background

Alterations in self-monitoring have been reported in patients with psychotic disorders, but it remains unclear to what degree they represent true indicators of familial vulnerability for psychosis.

Method

An error-correction action-monitoring task was used to examine self-monitoring in 42 patients with schizophrenia, 32 of their unaffected siblings and 41 healthy controls.

Results

Significant between-group differences in self-monitoring accuracy were found (χ2=29.3, p<0.0001), patients performing worst and unaffected siblings performing at an intermediate level compared to controls (all between-group differences p<0.05). In the combined group of healthy controls and unaffected siblings, detection accuracy was associated with positive schizotypy as measured by the Structured Interview for Schizotypy – Revised (SIS-R) (β=−0.16, s.e.=0.07, p=0.026), but not with negative schizotypy (β=−0.05, s.e.=0.12, p=0.694). In patients, psychotic symptoms were not robustly associated with detection accuracy (β=−0.01, s.e.=0.01, p=0.094), although stratified analysis revealed suggestive evidence for association in patients not currently using antipsychotic medication (β=−0.03, s.e.=0.01, p=0.052), whereas no association was found in patients on antipsychotic medication (β=−0.01, s.e.=0.01, p=0.426). A similar pattern of associations was found for negative symptoms.

Conclusions

Alterations in self-monitoring may be associated with familial risk and expression of psychosis. The association between psychotic symptoms and self-monitoring in patients may be affected by antipsychotic medication, which may explain previous inconsistencies in the literature.
Striatal function in relation to negative symptoms in schizophrenia
Authors: Ehrlich S. , Yendiki A. , Greve D. N. , Manoach D. S. , Ho B.-C. , White T. , Schulz S. C. , Goff D. C. , Gollub R. L. , Holt D. J.
Published: July 2011

Background

Previous studies have suggested that motivational aspects of executive functioning, which may be disrupted in schizophrenia patients with negative symptoms, are mediated in part by the striatum. Negative symptoms have been linked to impaired recruitment of both the striatum and the dorsolateral prefrontal cortex (DLPFC). Here we tested the hypothesis that negative symptoms are associated primarily with striatal dysfunction, using functional magnetic resonance imaging (fMRI).

Method

Working-memory load-dependent activation and gray matter volumes of the striatum and DLPFC were measured using a region-of-interest (ROI) approach, in 147 schizophrenia patients and 160 healthy controls. In addition to testing for a linear relationships between striatal function and negative symptoms, we chose a second, categorical analytic strategy in which we compared three demographically and behaviorally matched subgroups: patients with a high burden of negative symptoms, patients with minimal negative symptoms, and healthy subjects.

Results

There were no differences in striatal response magnitudes between schizophrenia patients and healthy controls, but right DLPFC activity was higher in patients than in controls. Negative symptoms were inversely associated with striatal, but not DLPFC, activity. In addition, patients with a high burden of negative symptoms exhibited significantly lower bilateral striatal, but not DLPFC, activation than schizophrenia patients with minimal negative symptoms. Working memory performance, antipsychotic exposure and changes in gray matter volumes did not account for these differences.

Conclusions

These data provide further evidence for a robust association between negative symptoms and diminished striatal activity. Future work will determine whether low striatal activity in schizophrenia patients could serve as a reliable biomarker for negative symptoms.
The Rise of Indirect Affirmative Action: Converging Strategies for Promoting “Diversity” in Selective Institutions of Higher Education in the United States and France
Authors: Sabbagh Daniel
Published: July 2011

A growing trend in the comparative politics literature on patterns of minority incorporation emphasizes the emerging policy convergence in this area, conventional oppositions between national models notwithstanding. This convergence is further illustrated by drawing upon the cases of two countries often analyzed within an “exceptionalist” framework and generally viewed as polar opposites as far as the political legitimacy and legal validity of race-based classifications are concerned: the United States and France. The analysis of recent programs designed to increase the “diversity” of the student body in selective institutions of higher education demonstrates that indirect affirmative action is the instrument around which French and U.S. policies have tended to converge. This increasingly visible convergence obtains in part because of the current move toward color-blindness as a matter of law in the United States. Yet it is also a reflection of the fact that the ultimate purpose of affirmative action in liberal democracies requires a measure of indirection and/or implicitness.
The Augustan Revolution Seen from the Mints of the Provinces
Authors: Burnett Andrew
Published: July 2011

This paper looks at the words, pictures and shapes that people in the Roman provinces placed on the thousands of coins that were made by each of several hundred cities, and uses the patterns that can be found to discuss the contribution provincial coins can make to our understanding of how relationships developed between the early Roman emperors, especially Augustus, and their audiences in provincial cities.
Cost-effectiveness of etanercept treatment in early active rheumatoid arthritis followed by dose adjustment
Authors: Kobelt Gisela , Lekander Ingrid , Lang Andrea , Raffeiner Bernd , Botsios Costantino , Geborek Pierre
Published: July 2011

Objectives: To explore the cost-effectiveness of early biologic treatment, followed by dose-reduction in the case of remission, of active rheumatoid arthritis (RA), compared with standard treatment with methotrexate (MTX) in Sweden.

Methods: Effectiveness (function, disease activity, erosions) in early RA for both alternatives was taken from a clinical trial comparing etanercept (ETA) combined with MTX to MTX alone. Patients discontinuing treatment can switch to another or their first biologic treatment. For patients in remission (Disease Activity Score [DAS28] < 2.6), ETA is reduced to half the dose. Return to full dose occurs when DAS28 reaches ≥ 3.2 again. Costs and utilities by level of functional capacity from an observational study are used. The model is analyzed as a micro-simulation and results are presented from the societal perspective for Sweden, for 10 years; costs (€2008) and effects are discounted at 3 percent. Sensitivity analysis was performed for the perspective, the time horizon, switching, and dose-reduction.

Results: The main analysis conservatively assumes 50 percent switching at discontinuation. The cost per quality-adjusted life-year (QALY) gained with early ETA/MTX treatment is €13,500 (societal perspective, incremental cost of €15,500 and incremental QALYs of 1.15). With 75 percent switching, the cost per QALY gained was €10,400. Over 20 years, the cost per QALY gained was €8,200. Results were further sensitive to the time patients remained on half dose and the perspective.

Conclusions and Policy Implications: This study combines clinical trial and clinical practice data to explore cost-effective treatment scenarios in early RA, including the use of biologics. Our results indicate that a situation where a considerable proportion of patients achieve remission, dose-adjustments will increase the cost-effectiveness of treatment.
Methylphenidate delivery mechanisms for the treatment of children with attention deficit hyperactivity disorder: Heterogeneity in parent preferences
Authors: Lloyd Andrew , Hodgkins Paul , Dewilde Sarah , Sasané Rahul , Falconer Shona , Sonuga Barke Edmund
Published: July 2011

Objectives:Extended-release therapies avoid the need for children with attention-deficit/hyperactivity disorder (ADHD) to take medication at school. Recently a transdermal delivery system has been developed which can allow symptom control all day long but with greater dosing flexibility. This study explored the parents' preferences regarding oral and transdermal therapy.

Methods:A nonsystematic and qualitative literature review and in-depth interviews with parents and physicians helped identify salient treatment attributes for a discrete choice experiment. Treatment attributes included mode of administration (tablet or transdermal), speed of onset (30–90 min); duration (lasts until 3–9pm) and ability to tailor the drug to different needs (no flexibility, limited flexibility, easy to adjust to different days). A convenience sample of parents of children treated for ADHD (n= 200) were recruited using a recruitment agency. Data were analyzed using generalized estimating equations (GEE).

Results:Parents' preferred once-a-day oral therapy (odds ratio [OR] = 1.76 [95 percent confidence interval {CI}, 1.43 – 2.18]); rapid speed of onset (OR = 1.22 [95 percent CI, 1.07 – 1.39]), and symptom control until 9pm(OR = 3.79 [95 percent CI, 2.98 – 4.82]). Analyses identified that 30 percent of parents preferred transdermal treatment and this subgroup preferred treatments with a fast onset of action.

Conclusions:This survey demonstrates that parents of ADHD children have different preferences for the ADHD treatments prescribed for their children. A distinct subgroup of parents prefer the transdermal therapy. These parents were less likely to be working and so monitoring compliance and doing after school activities may have been easier.
Mapping the increasing risk of human alveolar echinococcosis in Limburg, The Netherlands
Authors: TAKUMI K. , HEGGLIN D. , DEPLAZES P. , GOTTSTEIN B. , TEUNIS P. , VAN DER GIESSEN J.
Published: July 2011

The parasite Echinococcus multilocularis was first detected in The Netherlands in 1996 and repeated studies have shown that the parasite subsequently spread in the local population of foxes in the province of Limburg. It was not possible to quantify the human risk of alveolar echinococcosis because no relationship between the amount of parasite eggs in the environment and the probability of infection in humans was known. Here, we used the spread of the parasite in The Netherlands as a predictor, together with recently published historical records of the epidemiology of alveolar echinococcosis in Switzerland, to achieve a relative quantification of the risk. Based on these analyses, the human risk in Limburg was simulated and up to three human cases are predicted by 2018. We conclude that the epidemiology of alveolar echinococcosis in The Netherlands might have changed from a period of negligible risk in the past to a period of increasing risk in the forthcoming years.
Molecular typing of adenovirus circulating in a Colombian paediatric population with acute respiratory infection
Authors: ROJAS L. J. , JARAMILLO C. A. , MOJICA M. F. , ESCALANTE M. P. , DELGADO P.
Published: July 2011

Human adenoviruses (HAdV) cause a broad spectrum of diseases including acute respiratory infection (ARI), and are responsible for 5% of cases requiring hospitalization in children aged <5 years in Colombia; however, little is known about the circulating types, partly due to the lack of reliable typing tests. In order to evaluate a VA gene PCR-sequencing approach for identification of HAdV circulating types in a Colombian population, 52 nasopharyngeal aspirates/swabs from children with ARI were processed. After a BLAST analysis, matches with species B (41/48, 85·42%), C (6/48, 12·5%), and D (1/48, 2·08%) were found; and at the type level, type 3 (22/48, 45·83%) was the most frequent. This initial effort to expand our knowledge about the molecular epidemiology of HAdV circulating in Bogota, Colombia, showed that HAdV-B was the predominant circulating species in the study period and reports, for the first time in Colombia, the presence of HAdV-D in a respiratory sample.
Understanding the dermal light sense in the context of integrative photoreceptor cell biology
Authors: DESMOND RAMIREZ M. , SPEISER DANIEL I. , SABRINA PANKEY M. , OAKLEY TODD H.
Published: July 2011

While the concept of a dermal light sense has existed for over a century, little progress has been made in our understanding of the mechanisms underlying dispersed photoreception and the evolutionary histories of dispersed photoreceptor cells. These cells historically have been difficult to locate and positively identify, but modern molecular techniques, integrated with existing behavioral, morphological, and physiological data, will make cell identification easier and allow us to address questions of mechanism and evolution. With this in mind, we propose a new classification scheme for all photoreceptor cell types based on two axes, cell distribution (aggregatedvs.dispersed) and position within neural networks (first ordervs.high order). All photoreceptor cells fall within one of four quadrants created by these axes: aggregated/high order, dispersed/high order, aggregated/first order, or dispersed/first order. This new method of organization will help researchers make objective comparisons between different photoreceptor cell types. Using integrative data from four major phyla (Mollusca, Cnidaria, Echinodermata, and Arthropoda), we also provide evidence for three hypotheses for dispersed photoreceptor cell function and evolution. First, aside from echinoderms, we find that animals often use dispersed photoreceptor cells for tasks that do not require spatial vision. Second, although there are both echinoderm and arthropod exceptions, we find that dispersed photoreceptor cells generally lack morphological specializations that either enhance light gathering or aid in the collection of directional information about light. Third, we find that dispersed photoreceptor cells have evolved a number of times in Metazoa and that most dispersed photoreceptor cells have likely evolved through the co-option of existing phototransduction cascades. Our new classification scheme, combined with modern investigative techniques, will help us address these hypotheses in great detail and generate new hypothesis regarding the function and evolution of dispersed photoreceptor cells.
Infectious Rats and Dangerous Cows: Transnational Perspectives on Animal Diseases in the First Half of the Twentieth Century
Authors: KNAB CORNELIA
Published: July 2011

From the late nineteenth century onwards, the danger of animal diseases crossing national borders became increasingly apparent. The vast increase in the global trade in animals and animal products turned such diseases into a threat to both economic relations and public health, and called for international attention. Governments and groups of transnational experts began to develop cross-border networking strategies to counter the spread of animal diseases. Significant new developments started after the First World War with the establishment of a number of international animal health institutions, along with the Office International des Epizooties in Paris and the Veterinary Subcommittees of the League of Nations. This article traces the work of these two international animal health agencies and the interaction between their role as intergovernmental platforms and their capacity to define their own terms of reference.
Emergency Planning for Protection and Restoration of Services: Something We Should All Be Thinking About
Authors: Schumacher Elaine F.
Published: July 2011

We hear daily in the media about disasters, large and small, natural and man-made. We witness injury, loss of life, and destruction of homes and businesses. We get estimates of the economic consequences from the loss of property and income. We empathize as we watch the efforts of victims to recover and return to normal lives. And yes, we all hope that it never happens to us.
Using CMOS Cameras for Light Microscopy
Authors: Joubert James , Sharma Deepak
Published: July 2011

The push in consumer electronics over past decades has been toward smaller, faster, and cheaper products but with same or improved capabilities. The consumer imaging world has been no exception with the integration, for example, of functional complementary metal-oxide-semiconductor (CMOS) cameras into ever smaller cellular phones. The CMOS sensors have continued to develop and improve with increasing numbers of smaller, more sensitive pixels with larger photo-response capacity providing higher dynamic range. This technological expansion has inevitably spilled over into even the scientific imaging world, such as in biological light microscopy. This advancement of consumer CMOS digital camera technology invites comparison of CMOS cameras with the current standard charge coupled device (CCD) cameras in scientific imaging.