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• Five experimental studies examine gender discrimination in art judgments based on different criteria • Participants chose between male and female-originated artworks with/without artist information • We find evidence for statistical but not taste-based gender discrimination • Participants quasi discriminate on gender in a bias towards a correlated trait: artist fame We conduct five experimental studies to examine whether and what kind of gender discrimination explains deep and persistent gender gaps in the art market. 1112 participants chose between male and female-originated artworks with and without artist information. Gender-specific artist names did not affect personal preferences or preference norms. They did however cause significant swings towards male artworks when participants were incentivised to guess the more pedigreed or more expensive artwork. When artist name information was controlled, manipulating artist fame information shifted preference norms towards artworks of males, who are more famous on average. Overall we find no taste-based but significant statistical gender discrimination. We also find quasi gender discrimination, in which discrimination based on a particular characteristic (fame) may be falsely attributed to a highly-correlated one (gender). [ABSTRACT FROM AUTHOR]

This paper focuses on the experience of managing an exhibition project, undertaken by young professionals from the Museums of the Prussian Cultural Heritage Foundation in Berlin during the Covid-19 pandemic. The exhibition Status. Power. Movement was on display at the Berlin Cultural Forum (Kulturforum) from September 2020 to February 2021. In this interdisciplinary project, 13 co-curators selected 130 objects from 14 collections and asked how status is represented in movement. This article provides insight into how we experienced and dealt with the creation of our first exhibition amid an unprecedented crisis. Our project was confronted with the reality of the unfolding pandemic and empty museums. Key questions and concerns arose, such as: can the exhibition be opened? How to manage the planning uncertainty and, furthermore, how to deal with this ubiquitous event in our exhibition? As a result of the considerable restrictions, communication processes within the team and collaboration with external partners became extremely difficult. Our contribution adds a critical perspective from young professionals to the now-familiar discourse around museum work during a pandemic. In it, we share solutions we developed during the crisis, such as a Covid-19 themed intervention and the development of an online format for the exhibition. We additionally aim to show how we adapted our communication processes amid the crisis, working within a large cultural institution with multiple structural layers. Drawing on our experiences, we discuss issues of museum risk and crisis management. We also underline the need for a new critical discourse that would enable professionals to share experiences, responses and solutions to the ongoing pandemic and future crisis situations. [ABSTRACT FROM AUTHOR]

Plasma membrane H+‐ATPase pumps build up the electrochemical H+ gradients that energize most other transport processes into and out of plant cells through channel proteins and secondary active carriers. In Arabidopsis thaliana, the AUTOINHIBITED PLASMA MEMBRANE H+‐ATPases AHA1, AHA2 and AHA7 are predominant in root epidermal cells. In contrast to other H+‐ATPases, we find that AHA7 is autoinhibited by a sequence present in the extracellular loop between transmembrane segments 7 and 8. Autoinhibition of pump activity was regulated by extracellular pH, suggesting negative feedback regulation of AHA7 during establishment of an H+ gradient. Due to genetic redundancy, it has proven difficult to test the role of AHA2 and AHA7, and mutant phenotypes have previously only been observed under nutrient stress conditions. Here, we investigated root and root hair growth under normal conditions in single and double mutants of AHA2 and AHA7. We find that AHA2 drives root cell expansion during growth but that, unexpectedly, restriction of root hair elongation is dependent on AHA2 and AHA7, with each having different roles in this process. [ABSTRACT FROM AUTHOR]

The article aims to present the stages of the LEADER programme and its influence on greater activity and integration of inhabitants by, e.g. extending the knowledge of tradition and national heritage and the actions intended for the integration of local communities. It is noticeable particularly in the implementation of the activities within Axis 4 of the 2007-2013 Rural Development Programme. Positive changes in rural areas are a result of building strong social and human capitals, which are important factors of local development. The skills and the ability for cooperation of a local community allows it to implement many projects. The investments made by beneficiaries of the LEADER programme improve the level of living and the quality of life in the countryside. The effect is an improvement in physical infrastructure and tourist attractiveness as a result of care for the rural landscape and cultural heritage. The implementation of the LEADER programme is presented on the example of Wielkopolskie Voivodeship where the participation in actions for local communities is deeply ingrained. In order to show spatial differences in the activity of local entities under Local Action Groups in Wielkopolskie Voivodeship, classes were selected on the basis of funds received by local entities in the LAG areas. There are 36 Local Action Groups operating in Wielkopolska (of which 31 have seats in this region). [ABSTRACT FROM AUTHOR]

This paper states a unique classification to understand the source of the subharmonic vibrations of gas foil bearing (GFB) systems, which will experimentally and numerically tested. The classification is based on two cases, where an isolated system is assumed: Case 1 considers a poorly balance rotor, which results in increased displacement during operation and interacts with the nonlinear progressive structure. It is comparable to a Duffing-Oscillator. In contrast, for case 2 a well/perfectly balanced rotor is assumed. Hence, the only source of nonlinear subharmonic whirling results from the fluid film self-excitation. Experimental tests with different unbalance levels and GFB modifications confirm these assumptions. Furthermore, simulations are able to predict the self-excitations and synchronous and subharmonic resonances of the experimental test. The numerical model is based on a linearised eigenvalue problem. The GFB system uses linearised stiffness and damping parameters by applying a perturbation method on the Reynolds Equation. The nonlinear bump structure is simplified by a link-spring model. It includes Coulomb friction effects inside the elastic corrugated structure and captures the interaction between single bumps. [ABSTRACT FROM AUTHOR]

This paper gives a detailed overview of a shimmed first generation gas foil bearing (GFB). Three metal shims are inserted inside the elastic GFB structure between the bumps and the bearing sleeve. Dynamic shaker tests with a harmonic excitation are used for evaluating dynamic stiffness and damping of the elastic structure. In addition, a numerical structural bump model, based on a link-spring model, is applied to confirm the experimental results, where a dynamic friction model with pure Coulomb friction is used. It neglects Stribeck’s effects and avoids numerical problems in time domain analysis. Good agreement between experiments and simulations is observed. [ABSTRACT FROM AUTHOR]

Large interconnected power grids like the European transmission system tend to increase their power interchange as a result of the liberalisation of the electricity market as well as the increasing integration of intermittent power resources such as wind farms and photovoltaic. As a consequence of this, undesired circular power flows (loop flows) may occur, which means circulating active power between the control‐areas of several transmission system operators (TSOs). A superior survey of the occurrence of such phenomena in the context of operational control seems to be very useful, because uncontrolled power exchange reduces the transfer capabilities of power corridors and may cause unnecessary and avoidable line congestions or even overloads. This study demonstrates how the depth‐first search algorithm from graph theory can be adopted together with a superior cluster display of control areas in order to identify and visualise such kind of flows and to facilitate common situation awareness for operational control in control centres of TSOs in large interconnected systems. [ABSTRACT FROM AUTHOR]

Background: Whole-genome duplications in the ancestors of many diverse species provided the genetic material for evolutionary novelty. Several models explain the retention of paralogous genes. However, how these models are reflected in the evolution of coding and non-coding sequences of paralogous genes is unknown. Results: Here, we analyzed the coding and non-coding sequences of paralogous genes in Arabidopsis thaliana and compared these sequences with those of orthologous genes in Arabidopsis lyrata. Paralogs with lower expression than their duplicate had more nonsynonymous substitutions, were more likely to fractionate, and exhibited less similar expression patterns with their orthologs in the other species. Also, lower-expressed genes had greater tissue specificity. Orthologous conserved non-coding sequences in the promoters, introns, and 3' untranslated regions were less abundant at lower-expressed genes compared to their higher-expressed paralogs. A gene ontology (GO) term enrichment analysis showed that paralogs with similar expression levels were enriched in GO terms related to ribosomes, whereas paralogs with different expression levels were enriched in terms associated with stress responses. Conclusions: Loss of conserved non-coding sequences in one gene of a paralogous gene pair correlates with reduced expression levels that are more tissue specific. Together with increased mutation rates in the coding sequences, this suggests that similar forces of purifying selection act on coding and non-coding sequences. We propose that coding and non-coding sequences evolve concurrently following gene duplication. [ABSTRACT FROM AUTHOR]

This work identifies that pollen-specific genes in the sporophyte are repressed by histone positioning in promoters and epigenetic marks in gene bodies (methylation of histone-3 Lys-27).Tissue formation, the identity of cells, and the functions they fulfill, are results of gene regulation. The male gametophyte of plants, pollen, is outstanding in this respect as several hundred genes expressed in pollen are not expressed in the sporophyte. How pollen-specific genes are down-regulated in the sporophyte has yet to be established. In this study, we have performed a bioinformatics analysis of publicly available genome-wide epigenetics data of several sporophytic tissues. By combining this analysis with DNase I footprinting data, we assessed means by which the repression of pollen-specific genes in the Arabidopsis sporophyte is conferred. Our findings show that, in seedlings, the majority of pollen-specific genes are associated with histone-3 marked by mono- or trimethylation of Lys-27 (H3K27me1/H3K27me3), both of which are repressive markers for gene expression in the sporophyte. Analysis of DNase footprint profiles of pollen-specific genes in the sporophyte displayed closed chromatin proximal to the start codon. We describe a model of two-staged gene regulation in which a lack of nucleosome-free regions in promoters and histone modifications in open reading frames repress pollen-specific genes in the sporophyte. [ABSTRACT FROM PUBLISHER]

Empirical evidence concerning the demographics and development of Chinese nationalism is sparse but important for scholarship and policy. Its collection entails methodological challenges in access and reliability. We conducted a field experiment to measure nationalism in incentive-compatible choices among a diverse group of 447 Chinese subjects in a field setting. Our results demonstrate greater nationalism in female, older, less affluent and more rural respondents. We also find support for nationalism in professional and educated individuals. Our results provide qualified support for a middle-class nationalism in China. [ABSTRACT FROM PUBLISHER]

Sleep disturbances, present in more than 90% of major depressive disorder (MDD) patients, are moderated by sex in adult MDD. In particular, slow-wave electroencephalographic activity (SWA; 0.5-4 Hz) accumulation is low and dissipation impaired. This SWA abnormality in depressed adult males does not change with age, suggesting that SWA abnormality appears at early ages. The present study evaluated sex differences in SWA in adolescents with MDD compared to healthy controls. We evaluated regularized sleep-wake schedules at home for 5-7 days, followed by two consecutive nights of sleep EEG recording. The study included 104 participants, 52 symptomatic and depressed subjects (MDD: 20 males and 32 females) and 52 healthy controls (HC: 20 males and 32 females), aged 13-18 years. SWA power and dissipation, and duration and latencies to each Non-Rapid Eye Movement (NREM) sleep period were calculated for each group. Results showed that SWA accumulation in the first NREM period was lower and its dissipation across the night more irregular in MDD males compared to HC males (P<0.009). By contrast, SWA was equivalent in MDD and HC females. In conclusion, as reported in adult MDD, the accumulation and dissipation of SWA was abnormal in depressed adolescents, but only in males. SWA abnormalities in adolescent MDD may relate to different depressive symptoms in females and males. These results underscore the need to develop sex-specific therapies to enhance and restore SWA in depressed adolescents. [ABSTRACT FROM AUTHOR]

Visually scored and power spectral analyses (PSA) of polysomnography (PSG) recordings reveal abnormalities in alcohol dependence (AD) and major depressive disorder (MDD), including deficiencies in slow wave activity (SWA) during non-rapid eye movement (NREM) sleep. SWA parameters reflect the integrity of the homeostatic sleep drive, which have not been compared in those with AD or MDD. Ten men with AD were compared with 10 men with MDD and 10 healthy controls (HCs), all aged 20-40 years. They maintained an 11 pm to 6 am sleep schedule for 5-7 days, followed by 3 consecutive nights of PSG in the laboratory: night 1 for adaptation/screening; night 2 for baseline recordings; and night 3 as the challenge night, delaying sleep until 2 am. SWA was quantified with PSA across 4 NREM periods. Men with AD generated the least SWA at baseline. In response to sleep delay, HC men showed the expected SWA enhancement and a sharper exponential decline across NREM periods. Both the MDD and the AD groups showed a significantly blunted SWA response to sleep delay. Men with MDD had the least SWA in the first NREM period (impaired accumulation of sleep drive), whereas men with AD had the slowest SWA decay rate (impaired dissipation of sleep drive). These results suggest that both SWA generation and its homeostatic regulation are impaired in men with either AD or MDD. Finding interventions that selectively improve these different components of sleep homeostasis should be a goal of treatment for AD and MDD. [ABSTRACT FROM AUTHOR]

The article discusses a study on sleep spindle activity (SPA) in the early onset and elevated risk for depression. Sleep disturbances are common in major depressive disorder (MDD) but polysomnographic (PSG) abnormalities are common in adults while SPA is linked with neuroplasticity mechanisms during brain maturation and prevalent in children and adolescents. The study reveals that low SPA characterizes youth with MDD and those at high risk for MDD.

Based on theoretical reasoning it has been suggested that the reliability of findings published in the scientific literature decreases with the popularity of a research field. Here we provide empirical support for this prediction. We evaluate published statements on protein interactions with data from high-throughput experiments. We find evidence for two distinctive effects. First, with increasing popularity of the interaction partners, individual statements in the literature become more erroneous. Second, the overall evidence on an interaction becomes increasingly distorted by multiple independent testing. We therefore argue that for increasing the reliability of research it is essential to assess the negative effects of popularity and develop approaches to diminish these effects. [ABSTRACT FROM AUTHOR]

Abstract: The regulation of the alternation between rapid eye movement sleep (REMS) and non-rapid eye movement sleep (NREMS) is still a matter of much debate. It is also an important topic for psychiatric research, since both sleep components show anomalies in Major Depressive Disorders (MDD) and related syndromes. In previous studies on healthy controls, we showed preferential links of the number of ultradian cycles with REMS-related variables rather than with NREMS-related variables. REMS Latency (RL), for example, was shown to be inversely related to the number of cycles. The present study replicates these analyses in a group of 29 patients with MDD (age range: 23–56; 16 females), after two adaptation nights. Results showed significant correlations between the number of cycles and REMS, and between the number of cycles and RL, whereas correlations with NREMS were not significant. This indirectly supports regulation hypotheses considering REMS as the main focus of the oscillation, inhibiting and interrupting NREMS. Also, when the RL is shorter, there are more ultradian cycles than when the RL is long. This adds an interesting element in the elucidation of the physiological meaning of anomalies of RL. [Copyright &y& Elsevier]

Abstract: Economic globalisation promotes the interaction between individuals of different cultures. While experimental economists have established differences in the way individuals from different nations interact within their own cultures, behavioural differences in cross-cultural interactions have not been sufficiently explored. This paper reports the results of ultimatum game experiments in which Malaysian Chinese and UK subjects played opponents of their own as well as of the other culture. We confirm the existence of cultural difference in subject behaviour in both intra- and inter-national interactions. This evidence is discussed in terms of the possibility of a ‘clash of cultures’. [Copyright &y& Elsevier]

Publications in scientific journals contain a considerable fraction of our scientific knowledge. Analyzing data from publication data- bases helps us understand how this knowledge is obtained and how it changes overtime. In this study, we present a mathematical model for the temporal dynamics of data on the scientific content of publications. Our data set consists of references to thousands of genes in the >15 million publications listed in PubMed. We show that the observed dynamics may result from a simple process: Researchers predominantly publish on genes that already appear in many publications. This might be a rewarding strategy for researchers, because there is a positive correlation between the frequency of a gene in scientific publications and the journal impact of the publications. By comparing the empirical data with model predictions, we are able to detect unusual publication patterns that often correspond to major achievements in the field. We identify interactions between yeast genes from PubMed and show that the frequency differences of genes in publications lead to a biased picture of the resulting interaction network. [ABSTRACT FROM AUTHOR]

Objective: To quantify circadian rhythms in rest-activity cycles in depressed children and adolescents.Method: Rest-activity cycles were evaluated by actigraphy over five consecutive 24-hour periods in 100 children and adolescents, including 59 outpatients with major depressive disorder (MDD) and 41 healthy normal controls. Total activity, total light exposure, and time spent in light at more than 1,000 lux were averaged over the recording period for each participant. Time series analysis was used to determine the amplitude and period length of circadian rhythms in rest-activity.Results: Overall, adolescents with MDD had lower activity levels, damped circadian amplitude, and lower light exposure and spent less time in bright light than healthy controls. Among children, those with MDD showed lower light exposure and spent less time in bright light, but only depressed girls showed damped circadian amplitude. The sex differences were substantially greater in the MDD group than in the normal control group.Conclusions: These results confirm damped circadian rhythms in children and adolescents with MDD and highlight the influence of gender and age on these measures. [ABSTRACT FROM AUTHOR]

Reviews several human and animal studies in the neurobiology of depression. Neurotransmitter abnormalities; Animal models of major depressive disorder (MDD); Animal models of rapid eye movement sleep abnormalities in MDD.

Discusses significant differences in the temporal organization of rapid eye movement (REM) sleep microarchitecture in patients with major depressive disorder (MDD). REM latency longest in in men with MDD; Decline of slower frequencies across REM periods, with a significant REM period effect for delta, theta and alpha amplitude; Systematic temporal changes in electroencephalography over successive REM sleep periods.

This note is a contribution to the debate on Steven Brams's Theory of Moves. In particular, it aims to show that standard game-theoretic concepts can both account for and explain the statistics concerning mugging incidents that Brams presents to support the better predictive power of his own theory. [ABSTRACT FROM AUTHOR]

Background: Combination therapy with interferon alpha (IFNα) plus ribavirin has been shown to improve the sustained response rate in patients with chronic hepatitis C but there is little information regarding the lengths of time for this therapeutic regimen. In this study we therefore tried to evaluate whether the analysis of different virological parameters could provide new clues with respect to the early determination of the efficacy of this form of combination therapy. Furthermore, we also examined whether short-term induction combination therapy followed by IFNα alone is more effective than monotherapy in mounting an initial as well as a sustained virological response. Methods: 185 patients with histologically proven chronic hepatitis C (mean age 42 years (range 19–65 years); 110 males, 75 females) were enrolled in the study. The patients were randomly assigned to receive, over the first 12 weeks, either interferon alpha 2a 6 million units (MU) three times weekly plus ribavirin 14 mg/kg per day (n=93) or the same dose of IFNα alone (n=92). Patients with a virological response (serum HCV RNA undetectable) after 12 weeks were subsequently treated with 3 MU IFNα alone thrice weekly for a further 40 weeks. Otherwise, treatment was discontinued. After the end of treatment, patients were followed up for 24 weeks. Results: Patient characteristics at baseline were not significantly different in the two treatment groups. An initial virological response at week 12 was seen in 61 (66%) patients receiving IFNα plus ribavirin and in 44 (48%) being treated with IFNα alone (p=0.015) and this improvement in the response rate was mainly restricted to HCV genotype 1-infected patients (58% vs. 38%). In contrast, end-of-treatment (week 52) and sustained virological response rates were similar in both groups (37% vs. 29% and 26% vs. 17% [p=0.1], respectively). Interestingly, patients with HCV genotype 3, however, clearly benefited from short-term combination therapy. Thus, sustained virological response rates in these patients significantly increased from 25% (IFNα monotherapy) to 59% (combination therapy) (p=0.05). Conclusions: Short-term combined therapy for 12 weeks is more effective than the monotherapy with respect to the induction of an initial virological response but this effect applies only to genotype 1-infected patients. However, there is no significant difference between both therapeutic schedules with regard to the induction of sustained response. Although HCV genotype 3-infected patients seem to benefit from this short-term combined therapy, prolonged combined therapy may be necessary in HCV genotype 1-infected patients. [ABSTRACT FROM AUTHOR]

International aid charities face a dilemma by virtue of the White Saviour: Appeal photos of Caucasian helpers in Global South settings can build a bridge to donors or cause donor resentment with changing social norms. We examine four resulting empirical questions using a series of online studies: What is the White Saviour? How do White Saviour perceptions arise from charitable appeals? And what is their effect on both donation intentions and behaviour? We empirically identify two factors that constitute White Saviour perceptions: entitlement and ineffectiveness, along with the photo characteristics that raise them. Findings suggest that images with high White Saviour perceptions do not raise donations but can actually lower the propensity to donate. There is therefore no case for international NGOs to use such imagery, particularly given that it risks offending the people and communities they serve. [ABSTRACT FROM AUTHOR]

Monopolar EEG was recorded from lateral frontal and parietal sites with linked ear reference during sleep in 24 adults. Electrode placement followed the 10-20 International system. EEG was quantified using digital period analyses. The absolute difference in interhemispheric EEG parameters was compared for Stage 2, REM, and a slow wave sleep measure. The absolute difference measures reflect the degree of symmetry or asymmetry, regardless of the hemisphere of origin. Theta and delta activity in slow wave sleep was more asymmetrical than in either Stage 2 or REM. REM sleep was associated with the smallest asymmetries. These results do not support a right hemisphere REM, left hemisphere NREM relationship. Rather they suggest that REM sleep is associated with relative hemispheric symmetry whereas asymmetries are most prominent in slow wave sleep. Stage 2 sleep was significantly less asymmetrical than slow wave on a number of theta and delta measures. The significant differences between slow wave and Stage 2 sleep may denote functional differences within NREM sleep stages. [ABSTRACT FROM AUTHOR]

• PG545 synergizes with cisplatin or paclitaxel in vitro. • PG545 in combination with paclitaxel and cisplatin exhibited strong antitumor activity against endometrial cancer in vivo. • PG545 induces autophagy in type I and type II endometrial cancer cells. • ER stress, induced by PG545 further intensifies autophagy in endometrial cancer cells. The sulfated glycolipid PG545 shows promising antitumor activity in various cancers. This study was conducted to explore the effects and the mechanism of PG545 action in endometrial cancer (EC). PG545 exhibited strong synergy as assessed by the Chou-Talalay-Method in vitro when combined with cisplatin, or paclitaxel in both type I (Hec1B) and type II (ARK2) EC cell lines. While PG545 showed antitumor activity as monotherapy, a combination of PG545 with paclitaxel and cisplatin was highly effective in reducing the tumor burden and significantly prolonged survival of both Hec1B and ARK2 xenograft bearing mice. Mechanistically, PG545 elicits ER stress as an early response with resultant induction of autophagy. Our data demonstrated an increase in pERK, Bip/Grp78, IRE1α, Calnexin and CHOP/GADD153 within 6–24 hrs of PG545 treatment in EC cells. In parallel, PG545 also blocked FGF2 and HB-EGF mediated signaling in EC cells. Moreover, melatonin-mediated ER stress inhibition reduced PG545-mediated autophagy and PG545 in combination with cisplatin further heightened this stress response. Collectively these data indicate that PG545 exhibits strong synergistic effects with chemotherapeutics in vitro and showed promising antitumor activity in vivo. Our preclinical data indicates that in future studies PG545 can be a useful adjunct to chemotherapy in endometrial cancer. [ABSTRACT FROM AUTHOR]

Recently, large-scale experiments have provided new insights into the complex protein interaction network in yeast. However, previous analyses have shown that the number of interacting pairs that are common to different methods is extremely low and, therefore, less informative than expected. In this article, we show that comparing the connectivities of individual proteins can reveal that a common tendency between methods has been missed by the pairwise comparison of interactions. We found significant correlations between experimental methods and also between various in silico methods. Exceptionally, a computational method, gene neighbourhood, correlates with both in silico and experimental approaches. [Copyright &y& Elsevier]

By exploring time-series data from MEDLINE abstracts, we observe that only a few genes have been quoted with increasing frequency during the past 25 years. This is probably the result of selective pressure by the scientific community. Over the years, this selection has produced an extreme power law distribution of the information available for individual genes. Interestingly, those genes that are successfully selected are not necessarily the most important genes to the cell. To stress the implication of this finding we show that there is no correlation between a gene''s impact in the scientific literature and its centrality in protein-interaction networks. [Copyright &y& Elsevier]

Background: Studies have demonstrated that decreases in slow-wave activity (SWA) predict decreases in depressive symptoms in those with major depressive disorder (MDD), suggesting that there may be a link between SWA and mood. The aim of the present study was to determine if the consequent change in SWA regulation following a mild homeostatic sleep challenge would predict mood disturbance. Methods: Thirty-seven depressed and fifty-nine healthy adults spent three consecutive nights in the sleep laboratory. On the third night, bedtime was delayed by 3 h, as this procedure has been shown to provoke SWA. The Profile of Mood States questionnaire was administered on the morning following the baseline and sleep delay nights to measure mood disturbance. Results: Results revealed that following sleep delay, a lower delta sleep ratio, indicative of inadequate dissipation of SWA from the first to the second non-rapid eye movement period, predicted increased mood disturbance in only those with MDD. Conclusions: These data demonstrate that in the first half of the night, individuals with MDD who have less SWA dissipation as a consequence of impaired SWA regulation have greater mood disturbance, and may suggest that appropriate homeostatic regulation of sleep is an important factor in the disorder. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about gene network.

This paper reports a study which examined the impact of computer game experience on behaviour observed inside a virtual world. A social networking world was used, which was owned and run by the research team and a dataset capturing the behaviour of 195 subjects was extracted from the world's event logs. Four broad areas were analysed: communication, movement, avatar creation and world customization. Highly significant differences were found in text communication. Less significant differences were found in movement and avatar creation, and none were found in the customization of the world. [ABSTRACT FROM PUBLISHER]

Abstract: We explore the scientific potential of virtual worlds for experimental economics in terms of the subject pools and experimental platforms they present. Our results offer tentative, qualified support for virtual world experimentation. Overall, the behaviour of virtual subjects recruited, incentivised and observed within Second Life across a range of five standard experimental games was not found to differ significantly from established standard results. In addition, we identify certain methodological opportunities and challenges which confront virtual world experimenters. [Copyright &y& Elsevier]

Abstract: Objective: The purpose of the study was to evaluate quantitative sleep electroencephalogram (EEG) frequencies in monozygotic twins discordant for chronic fatigue syndrome. Methods: Thirteen pairs of female twins underwent polysomnography. During the first night, they adapted to the sleep laboratory, and during the second night, their baseline sleep was assessed. Visual stage scoring was conducted on sleep electroencephalographic records according to standard criteria, and power spectral analysis was used to quantify delta through beta frequency bands, processed in 6-s blocks. Data were averaged across sleep stage within each twin and coded for sleep stage and the presence or absence of chronic fatigue syndrome (CFS). A completely within-subjects repeated measure multivariate analysis of variance evaluated twin pairs by frequency band by sleep stage interactions and simple effects. The relationship between alpha and delta EEG was also assessed across twin pairs. Results: No significant differences in spectral power in any frequency band were found between those with CFS and their nonfatigued cotwins. Phasic alpha activity, coupled with delta was noted in five subjects with CFS but was also present in 4/5 healthy twins, indicating this finding likely reflects genetic influences on the sleep electroencephalogram rather than disease-specific sleep pathology. Conclusions: The genetic influences on sleep polysomnography and microarchitecture appear to be stronger than the disease influence of chronic fatigue syndrome, despite greater subjective sleep complaint among the CFS twins. EEG techniques that focus on short duration events or paradigms that probe sleep regulation may provide a better description of sleep abnormalities in CFS. [Copyright &y& Elsevier]

Although the family Sciuridae is large and well known, phylogenetic analyses are scarce. We report on a comprehensive molecular phylogeny for the family. Two nuclear genes (c-myc and RAG1) comprising approximately 4500 bp of data (most in exons) are applied for the first time to rodent phylogenetics. Parsimony, likelihood, and Bayesian analyses of the separate gene regions and combined data reveal five major lineages and refute the conventional elevation of the flying squirrels (Pteromyinae) to subfamily status. Instead, flying squirrels are derived from one of the tree squirrel lineages. C-myc indels corroborate the sequence-based topologies. The common ancestor of extant squirrels appears to have been arboreal, confirming the fossil evidence. The results also reveal an unexpected clade of mostly terrestrial squirrels with African and Holarctic centers of diversity. We present a revised classification of squirrels. Our results demonstrate the phylogenetic utility of relatively slowly evolving nuclear exonic data even for relatively recent clades. [Copyright &y& Elsevier]

Objective: The present study evaluated the effects of vagus nerve stimulation (VNS) on sleep in seven treatment-resistant depressed outpatients.Methods: Sleep studies were conducted in the laboratory at baseline and 10-12 weeks after VNS implantation while the concomitant psychotropic medication regimen was unchanged. Standard sleep macroarchitecture based on visual stage and assessment of ultradian sleep electroencephalographic (EEG) rhythms were measured on all nights.Results: An overall significant treatment effect on sleep macroarchitecture was obtained by MANOVA. Decreased awake time, decreased Stage 1 sleep and increased Stage 2 sleep were evident post-VNS, although univariate analyses did not reach significance. In addition, the strength or amplitude of ultradian sleep EEG rhythms more than doubled on VNS and was restored to within normal range.Conclusion: VNS improved the clinical symptoms of depression and sleep architecture. Results suggest that treatment-resistant depressed patients have dampened sleep EEG rhythms that are restored to near-normal amplitudes with VNS treatment. [ABSTRACT FROM AUTHOR]

Background/Aims: Combination therapy with interferon-α (IFN-α) plus ribavirin is more efficacious than IFN-α monotherapy in previously untreated patients with chronic hepatitis C and patients with IFN-α relapse. Only limited data are available in IFN-α non-responders. In a multicenter trial we therefore evaluated the efficacy of combination therapy in IFN-α-resistant chronic hepatitis C. Methods: Eighty-two patients (mean age 46.8 years, 54 males, 28 females) with chronic hepatitis C were treated with IFN-α-2a (3 × 6 MIU/week) and ribavirin (14 mg/kg daily) for 12 weeks. Thereafter, treatment was continued only in virological responders (undetectable serum HCV RNA at week 12) with an IFN-α dose of 3 × 3 MIU/week and without ribavirin for a further 9 months. The primary study endpoint was an undetectable HCV RNA by RT-PCR at the end of the 24-week follow-up period. Results: After 12 weeks of combination therapy, an initial virological response was observed in 29 of 82 (35.4%) patients. Due to a high breakthrough rate after IFN-α dose reduction and ribavirin discontinuation, an end-of-treatment response was only achieved in 12 of 82 (14.6%) patients. After the follow-up period, a sustained virological response was observed in 8 of 82 (9.8%) patients. Infection with HCV genotype 3 was the only pretreatment parameter, which could predict a sustained response (HCV-1, 5%; HCV-3, 57.1%; p < 0.001). Conclusions: Despite a high initial response rate of 35.4%, sustained viral clearance was achieved only in 9.8% of the retreated primary IFN-α non-responders. Higher IFN-α induction and maintenance dose, as well as prolonged ribavirin treatment may possibly increase the virological response rates in non-responders, particularly in those infected by HCV-1.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The purpose of this study was to correlate subjective sleep characteristics based on questionnaire response, and objective sleep EEG features based on polysomnography, in 52 patients with major depressive disorders (MDD) and 49 healthy controls. With the exception of the number of awakenings, subjective and objective sleep measures were strongly correlated in both groups. Patients and controls were able to accurately judge time in bed, total sleep time and sleep latency. However, sleep quality, depth, and how rested participants felt upon awakening were not strongly correlated with objective sleep characteristics, particularly in those with MDD. The findings suggest that estimates such as total sleep time and sleep latency, obtained from questionnaire data, bear a strong resemblance to objective polysomnographic characteristics in both those with MDD and healthy controls. Patients with MDD do not show sleep-state misperceptions although depressed women are more accurate in estimating sleep characteristics than depressed men. [ABSTRACT FROM AUTHOR]

Background: Dimensions of social location such as socioeconomic position or sex/gender are often associated with low response rates in epidemiological studies. We applied an intersectionality-informed approach to analyze non-response among population strata defined by combinations of multiple dimensions of social location and subjective health in a health survey in Germany. Methods: We used data from the cross-sectional sample of the German Health Interview and Examination Survey for Adults (DEGS1) conducted between 2008 and 2011. Information about non-responders was available from a mailed non-responder questionnaire. Intersectional strata were constructed by combining all categories of age, sex/gender, marital status, and level of education in scenario 1. Subjective health was additionally used to construct intersectional strata in scenario 2. We applied multilevel analysis of individual heterogeneity and discriminatory accuracy (MAIHDA) to calculate measures of discriminatory accuracy, proportions of non-responders among intersectional strata, as well as stratum-specific total interaction effects (intersectional effects). Markov chain Monte Carlo methods were used to estimate multilevel logistic regression models. Results: Data was available for 6,534 individuals of whom 36% were non-responders. In scenario 2, we found weak discriminatory accuracy (variance partition coefficient = 3.6%) of intersectional strata, while predicted proportions of non-response ranged from 20.6% (95% credible interval (CI) 17.0%-24.9%) to 57.5% (95% CI 48.8%-66.5%) among intersectional strata. No evidence for intersectional effects was found. These results did not differ substantially between scenarios 1 and 2. Conclusions: MAIHDA revealed that proportions of non-response varied widely between intersectional strata. However, poor discriminatory accuracy of intersectional strata and no evidence for intersectional effects indicate that there is no justification to exclusively target specific intersectional strata in order to increase response, but that a combination of targeted and population-based measures might be appropriate to achieve more equal representation. [ABSTRACT FROM AUTHOR]

Background: There are complex, bidirectional associations between major depressive disorder and insomnia. In the present study, we evaluated insomnia as a moderator of response to antidepressant therapy in the context of a sleep manipulation (time in bed restriction) for major depressive disorder. Methods: Fifty-eight adults with major depressive disorder received 8 weeks of fluoxetine 20-40 mgs and were randomized to 8 hr time in bed (8h TIB) or 6 hr time in bed (6h TIB) for the first 2 weeks (participants in the 6h TIB condition were further randomized to a delayed bedtime (Late Bedtime) or advanced rise time (Early Rise Time) group). Insomnia was assessed at baseline using the Insomnia Severity Index. Depression symptom severity was determined by the clinician-rated 17-item Hamilton Rating Scale for Depression (HAMD-17), completed weekly. Results: A group by time interaction was observed whereby HAMD-17 scores were higher for participants assigned to the 6h TIB group (without insomnia, weeks 3 through 7; with insomnia from week 3 through 6, ps <.05) relative to participants without insomnia assigned to the 8h TIB group. There were no differences in HAMD-17 scores for participants with insomnia in the 6h TIB group relative to the 8h TIB group. Conclusion: These preliminary findings suggest that response to fluoxetine may be hindered by TIB restriction in individuals without insomnia. Individuals with insomnia respond similarly to fluoxetine regardless of whether their TIB is restricted. Limitations include exclusive use of self-report measures to categorize insomnia, and small sample sizes in several of the subgroups. [ABSTRACT FROM AUTHOR]

Few studies have examined relationships between circadian rhythms and unipolar major depressive disorder. Further, no study to date has examined circadian markers as predictors of response to depression treatment. In the present study, we examined associations between circadian timing and its alignment with sleep and depression severity in 30 adults with major depressive disorder who completed a randomized controlled trial of two weeks of time in bed (TIB) restriction administered adjunctive to fluoxetine, with a focus on sex differences. Thirty adults with major depressive disorder received 8 weeks of fluoxetine 20–40 mgs and were randomized to 8 h TIB or 6 h TIB for the first 2 weeks. Participants in the 6 h TIB condition were further randomized to a delayed bedtime or advanced risetime group. Circadian measures included dim light melatonin onset (DLMO) and the difference between DLMO and midsleep point (i.e., phase angle difference). Depression was assessed using the Hamilton Rating Scale for Depression. For females, a phase delay after 2 weeks of fluoxetine and the experimental TIB manipulation was associated with a poorer response to fluoxetine, and depression severity was negatively correlated with phase angle difference, whereas males showed a positive correlation between depression severity and phase angle difference. [ABSTRACT FROM AUTHOR]

Background: Suicide is a major public health concern, and a barrier to reducing the suicide rate is the lack of objective predictors of risk. The present study considers whether quantitative sleep electroencephalography (EEG) may be a neurobiological correlate of suicidal ideation.Methods: Participants included 84 (45 female, mean age=26.6) adults diagnosed with major depressive disorder (MDD). The item that measures thoughts of death or suicide on the Quick Inventory of Depressive Symptomatology (QIDS) was used to classify 47 participants as low suicidal ideation (24 females, mean age=26.1) and 37 as high suicidal ideation (21 females, mean age=27.3). Data were obtained from archival samples collected at the University of Michigan and University of Texas Southwestern Medical Center between 2004 and 2012. Sleep EEG was quantified using power spectral analysis, and focused on alpha, beta, and delta frequencies.Results: Results indicated that participants with high compared to low suicidal ideation experienced 1) increased fast frequency activity, 2) decreased delta activity, and 3) increased alpha-delta sleep after adjusting for age, sex, depression, and insomnia symptoms.Limitations: Limitations include the exclusion of imminent suicidal intent, a single suicidal ideation item, and cross-sectional archival data.Conclusions: This is one of the first studies to provide preliminary support that electrophysiological brain activity during sleep is associated with increased suicidal ideation in MDD, and may point toward central nervous system (CNS) hyperarousal during sleep as a neurobiological correlate of suicidal ideation. [ABSTRACT FROM AUTHOR]

Sleep difficulties are highly prevalent in depression, and appear to be a contributing factor in the development and maintenance of symptoms. However, despite the generally acknowledged relationship between sleep and depression, the neurophysiological substrates underlying this relationship still remain unclear. Two main hypotheses were tested in this study. The first hypothesis states that sleep in depression is characterized by inadequate generation of restorative sleep, as indexed by reduced amounts of slow-wave activity. Conversely, the second hypothesis states that poor sleep in depression is due to intrusions of fast-frequency activity that may be reflective of a hyperaroused central nervous system. This study aimed to test both hypotheses in a large sample of individuals with clinically validated depression, as well as to examine sex as a moderator. Results suggest that depression is better characterized by an overall decrease in slow-wave activity, which is related to elevated anxious and depressed mood the following morning. Results also suggest that females may be more likely to experience fast frequency activity related to depression symptom severity. [ABSTRACT FROM AUTHOR]

While prior research has demonstrated a paradoxical antidepressant effect of slow-wave disruption (SWD), the specific dimensions of depression affected is still unclear. The current study aimed to extend this research by utilizing a dimensional approach in examining the antidepressant effects of SWD. Of particular interest is the affective dimension, as negative affect in depression is arguably the most salient characteristic of depression. This sample included 16 individuals with depression (10 female) recruited from the community. Participants slept in the lab for three nights (adaptation, baseline night, and SWD) with polysomnography, and completed measures of negative affect and depression severity the following morning. Results show that reduction in delta power was linearly associated with improved negative affect. Comparison of individual change scores revealed that half of the individuals showed improved negative affect, which is comparable to the reported 40–60% antidepressant response rate to sleep deprivation. Results suggest that vulnerability in the sleep homeostatic system may be a contributing individual differences factor in response to slow-wave disruption in depression. [ABSTRACT FROM AUTHOR]