bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of monobutyrin and tributyrin on liver lipid profile, caecal microbiota composition and SCFA in high-fat diet-fed rats
Authors: Nguyen Thao Duy , Prykhodko Olena , Fåk Hållenius Frida , Nyman Margareta
Published: October 2017

Butyric acid has been shown to have suppressive effects on inflammation and diseases related to the intestinal tract. The aim of the present study was to investigate whether supplementation of two glycerol esters, monobutyrin (MB) and tributyrin (TB), would reach the hindgut of rats, thus having an effect on the caecal profile of SCFA, microbiota composition and some risk markers associated with chronic inflammation. For this purpose, rats were fed high-fat diets after adding MB (1 and 5 g/kg) and TB (5 g/kg) to a diet without any supplementation (high-fat control; HFC). A low-fat (LF) diet was also included. In the liver, total cholesterol concentrations, LDL-cholesterol concentrations, LDL:HDL ratio, and succinic acid concentrations were reduced in rats given the MB and TB (5 g/kg) diets, compared with the group fed the HFC diet. These effects were more pronounced in MB than TB groups as also expressed by down-regulation of the gene Cyp8b1. The composition of the caecal microbiota in rats fed MB and TB was separated from the group fed the HFC diet, and also the LF diet, as evidenced by the absence of the phylum TM7 and reduced abundance of the genera Dorea (similar to LF-fed rats) and rc4-4. Notably, the caecal abundance of Mucispirillum was markedly increased in the MB group compared with the HFC group. The results suggest that dietary supplementation of MB and TB can be used to counteract disturbances associated with a HFC diet, by altering the gut microbiota, and decreasing liver lipids and succinic acid concentrations.
A Meta-Analytic Review of Gender-Role Dimensions and Relationship Satisfaction
Authors: Ta Vivian P.
Published: October 2017

Multilevel meta-analytic techniques were used to examine the overall relationship between self-reported gender-role dimensions (psychological femininity and psychological masculinity) and self-reported relationship satisfaction. Twenty-six studies (43 effect sizes) were included in the femininity-relationship satisfaction meta-analysis, and 26 studies (43 effect sizes) were included in the masculinity-relationship satisfaction meta-analysis. Femininity revealed a stronger association with relationship satisfaction than masculinity: there was a medium relationship (r= .28) between femininity and relationship satisfaction and a small relationship (r= .13) between masculinity and relationship satisfaction. Sex/gender was not a moderator in either meta-analysis. Publication biases were not detected. Implications and recommendations are discussed.
Mycoprotein represents a bioavailable and insulinotropic non-animal-derived dietary protein source: a dose–response study
Authors: Dunlop Mandy V. , Kilroe Sean P. , Bowtell Joanna L. , Finnigan Tim J. A. , Salmon Deborah L. , Wall Benjamin T.
Published: October 2017

The anabolic potential of a dietary protein is determined by its ability to elicit postprandial rises in circulating essential amino acids and insulin. Minimal data exist regarding the bioavailability and insulinotropic effects of non-animal-derived protein sources. Mycoprotein is a sustainable and rich source of non-animal-derived dietary protein. We investigated the impact of mycoprotein ingestion, in a dose–response manner, on acute postprandial hyperaminoacidaemia and hyperinsulinaemia. In all, twelve healthy young men completed five experimental trials in a randomised, single-blind, cross-over design. During each trial, volunteers consumed a test drink containing either 20 g milk protein (MLK20) or a mass matched (not protein matched due to the fibre content) bolus of mycoprotein (20 g; MYC20), a protein matched bolus of mycoprotein (40 g; MYC40), 60 g (MYC60) or 80 g (MYC80) mycoprotein. Circulating amino acid, insulin and uric acid concentrations, and clinical chemistry profiles, were assessed in arterialised venous blood samples during a 4-h postprandial period. Mycoprotein ingestion resulted in slower but more sustained hyperinsulinaemia and hyperaminoacidaemia compared with milk when protein matched, with overall bioavailability equivalent between conditions (P>0·05). Increasing the dose of mycoprotein amplified these effects, with some evidence of a plateau at 60–80 g. Peak postprandial leucine concentrations were 201 (sem 24) (30 min), 118 (sem 10) (90 min), 150 (sem 14) (90 min), 173 (sem 23) (45 min) and 201 (sem 21 (90 min) µmol/l for MLK20, MYC20, MYC40, MYC60 and MYC80, respectively. Mycoprotein represents a bioavailable and insulinotropic dietary protein source. Consequently, mycoprotein may be a useful source of dietary protein to stimulate muscle protein synthesis rates.
RELATIONSHIP BETWEEN ORPHANHOOD STATUS, LIVING ARRANGEMENTS AND SEXUAL DEBUT: EVIDENCE FROM FEMALES IN MIDDLE ADOLESCENCE IN SOUTHERN AFRICA
Authors: Shoko Mercy , Ibisomi Latifat , Levin Jonathan , Ginsburg Carren
Published: October 2017

This study examined the relationship between orphanhood status, living arrangements and sexual debut. The study is important in the context of southern Africa, where a substantial number of children live apart from their parents because the parent is dead or living elsewhere, and where female adolescents face disproportionate sexual and reproductive health risks. Data for female adolescents were taken from Demographic and Health Surveys conducted in seven southern African countries. Unadjusted and adjusted hazard ratios of sexual debut were estimated using Cox Proportional Hazard models. The results from multivariate analyses showed that non-co-residence with biological parents was significantly associated with higher risk of sexual debut in five of the seven countries. Using pooled data, the results showed that father absence was associated with higher risk of sexual debut – whether the father was deceased or living elsewhere. Interventions to delay sexual debut among female adolescents should seek to promote father–adolescent co-residence and improve access to education.
Hymenolepis diminuta and Rodentolepis nana (Hymenolepididae: Cyclophyllidea) in urban rodents of Gran La Plata: association with socio-environmental conditions
Authors: Fitte B. , Robles M.R. , Dellarupe A. , Unzaga J.M. , Navone G.T.
Published: October 2017

The aim of this survey was to study two Hymenolepididae species in urban rodents, Rattus rattus and Rattus norvegicus, and to analyse factors that favour their presence in the environment and pose a sanitary risk. Hymenolepis diminuta and Rodentolepis nana were found in R. rattus and R. norvegicus in different proportions. Values of prevalence, mean abundance and mean intensity were recorded, and new morphometric characters were described, adding to previously known information. No significant differences were found. However, the results revealed that there is a tendency for these parasites to develop in areas with deficient socio-structural conditions and in water bodies. This study thereby shows that certain areas on the periphery of the Gran La Plata favour the existence of rodents, which act as sentinels of zoonotic diseases, and stresses the need to take action to minimize them in order to avoid putting human and animal health at risk.
Analysis of lead pollution levels within an urban ecosystem using the cestode Hymenolepis diminuta and its rat hosts as bioindicators
Authors: Tripodi M.A. , Hancke D. , Suarez O.V.
Published: October 2017

The overall goal of this study was to use the Rattus spp./Hymenolepis diminuta model to assess environmental lead pollution in different landscape units of an urban ecosystem. Rats of the genus Rattus were collected from three shanty towns and three residential neighbourhoods of the city of Buenos Aires. Concentrations of lead in the livers of wild rats and in their parasite H. diminuta were measured using inductively coupled plasma mass spectrometry (ICP-MS). The landscape unit and tissue type had a significant effect on lead concentration, being higher in residential neighbourhoods as well as in H. diminuta tissue. Nevertheless, no significant differences were found for the mean lead concentration in livers between uninfected and infected rats. Since the available information describing heavy-metal pollution within the city of Buenos Aires is scarce, the results of this study allow us to update data about the extent of biologically available lead contamination. Considering that rats and H. diminuta are distributed worldwide, this monitoring system for lead pollution might be applied successfully in other urban ecosystems.
Potent nematicidal activity of phenolic derivatives on Meloidogyne incognita
Authors: Aissani N. , Balti R. , Sebai H.
Published: October 2017

The present study describes the nematicidal activity of ten selected phenolic derivatives using the root knot nematode, Meloidogyne incognita, model. Nematicidal activity was then correlated with the anti-oxidant power. The highest nematicidal activity was recorded for p-nitrophenol followed by m-nitrophenol, o-nitrophenol and p-bromophenol, with an EC50 after 1 day of immersion of about 0.70 ± 0.64, 8.14 ± 5.49, 15.79 ± 10.81 and 25.92 ± 11.37 μg/ml, respectively. The structure–activity relationship indicates that the nitro-group at position 4 on the phenolic ring (p-nitrophenol) is very important for nematicidal activity, followed by that at position 2 (o-nitrophenol) and position 3 (m-nitrophenol). p-Nitrophenol showed the highest nematicidal activity with the corresponding lowest anti-oxidant activity of about 97 ± 20 μg/ml. In conclusion, these findings suggest that phenolic derivatives could be considered as potent nematicidal agents and be integrated in the pest-management system.
Quality aspects of Crassostrea gigas (Thunberg, 1793) reared in the Varano Lagoon (southern Italy) in relation to marketability
Authors: Cilenti Lucrezia , Scirocco Tommaso , Specchiulli Antonietta , Vitelli Maria Luigia , Manzo Cristina , Fabbrocini Adele , Santucci Angela , Franchi Massimo , D'adamo Raffaele
Published: October 2017

Shellfish culture, based on ecological and market assessment, is considered a driving force for socio-economic change in ecologically complex coastal systems such as lagoons throughout the Mediterranean area. To diversify fish production, the Pacific oyster Crassostrea gigas was cultured at commercial farms in the Varano Lagoon (SE Italy). The aims of this study were to evaluate through four condition indices (CI, CICG, CIE and AFNOR index), the Polydora index (PI), lipid content, quality and market aspects of oysters reared at two different sites (FO and LA) of the Varano Lagoon, which are characterized by different hydrodynamic conditions. The results of this study highlighted the potential economic benefits associated with sustainable aquaculture development in the Varano Lagoon, proving that the area surrounding the LA site was more suitable for oyster culture, reaching commercial size (60 mm) in a shorter time (6–8 months). Higher growth performance of oysters was observed in the spring, when the nutrient availability positively affected the feeding response of suspension feeders. The opposite was found in winter and in summer, when the decrease in growth could be due to the reduction of nutrient and to the increase of salinity, TSM and ISM. The presence of the mud blister worm (Polydora sp.) during rearing could be a real problem, as it damages oyster market value and threatens serious financial loss to the local farmers.
Understanding frailty: meanings and beliefs about screening and prevention across key stakeholder groups in Europe
Authors: SHAW RACHEL L. , GWYTHER HOLLY , HOLLAND CAROL , BUJNOWSKA-FEDAK MARIA , KURPAS DONATA , CANO ANTONIO , MARCUCCI MAURA , RIVA SILVIA , D'AVANZO BARBARA
Published: October 2017

Innovative methods to manage frailty are critical to managing the needs of an ageing population. Evidence suggests there are opportunities to reverse or prevent frailty through early intervention. However, little is known about older adults’, families’ and practitioners’ beliefs about the malleability of frailty. This study examined European stakeholders’ accounts of the acceptability and feasibility of frailty screening and prevention to inform future intervention development. Semi-structured focus groups and individual interviews were conducted in three European Union countries (Italy, Poland and the United Kingdom) with key stakeholders – frail and non-frail older adults, family care-givers, and health and social care professionals. Thematic analysis identified four themes: synchronicity between the physical and the psychological in frailty, living with frailty in the social world, the need for a new kind of care, and screening for and preventing frailty. Findings emphasised the need for a holistic approach to frailty care and early intervention. Integrated care services and advocacy were important in the organisation of care. Central to all stakeholders was the significance of the psychological and social alongside the physical elements of frailty and frailty prevention. Support and care for older adults and their family care-givers needs to be accessible and co-ordinated. Interventions to prevent frailty must encompass a social dimension to help older adults maintain a sense of self while building physical and psychological resilience.
Taking history seriously in IR: Towards a historicist approach
Authors: Cello Lorenzo
Published: October 2017

IR scholars have always invoked history as a valuable resource for understanding the present. However, the question of how should we go about investigating and interpreting the past is rarely asked, let alone answered. While most IR approaches are anchored to the attempt to situate oneself outside history – reading the past in terms of the present or in terms of a hypothetical future – this article strives to redress the kind of historical perspective adopted, if at all, by IR scholars. It does so by advancing a distinctive historicist approach that emphasises the importance of understanding past practices and discourses in their own historical and intellectual contexts. In order to substantiate this claim, the article goes on to critically engage with recent calls to historicise intervention in IR, arguing that a historicist mode of analysis represents a corrective to presentism as well as an alternative route into present-day debates.
‘Another National Anthem’: Public Memory, Burkean Identification, and the Musical Assassins
Authors: Schrader Valerie Lynn
Published: October 2017

In this article Valerie Lynn Schrader examines the musical Assassins through the rhetorical lenses of public memory and Kenneth Burke's theory of identification. Offering a close textual analysis of the musical's script and cast recording, she argues that Assassins, along with its audiences, serves to co-create a public memory of the men and women who attempted to assassinate Presidents of the United States of America. Her article contends that Assassins creates a chilling consubstantiality between the characters in the musical and theatregoers through Burkean identification, which may cause cognitive dissonance for many audience members. Through identifying key themes in the musical, she argues that these both connect with the assassins' motives and are common human experiences, serving not only to create public memory of the stories, but also to humanize the assassins and create a bond between audience and characters – while the song ‘Something Just Broke’ undermines this connection and encourages audience members to identify with the mourning American public. Valerie Lynn Schrader is Associate Professor of Communications and Interim Director of Academic Affairs at the Schuylkill Campus of the Pennsylvania State University. Her research focuses on rhetorical messages in theatre works, especially musical theatre productions. She is herself a classically trained lyric soprano/soubrette.
Online Role-playing Games and the Definition of Theatre
Authors: Nellhaus Tobin
Published: October 2017

Online role-playing games are a form of entertainment in which players create characters and improvisationally perform scenes together within a digital virtual world. It has many theatre-like aspects, which raises the question of whether it is in fact a form of theatre. To answer that question, however, one must first have a definition of theatre – an issue with disciplinary consequences – and in this article Tobin Nellhaus develops a definition founded on social ontology, suggesting that theatrical performance, unlike other social practices, replicates society's ontology. From that perspective, online role-playing meets the definition of theatre. But its digital environment raises another set of problems, since embodiment, space, and presence in online role-playing are necessarily unlike what we experience in traditional theatre. Here, Nellhaus brings these three aspects of performance together through the concept of embodied social presence, showing how they operate in both customary theatre and online role-playing. Tobin Nellhaus is an independent scholar who was Librarian for Performing Arts, Media, and Philosophy at Yale University. He has published mainly on the relationship between theatre and communication practices, and on critical realist theory in theatre historiography. He is the General Editor of the third edition of Theatre Histories (London: Routledge, 2016), and the author of Theater, Communication, Critical Realism (New York: Palgrave Macmillan, 2010).
Crush Humanity One More Time: Martin McDonagh's The Pillowman in Žižekian Terms
Authors: Akşehir-Uygur Mahinur
Published: October 2017

Martin McDonagh's The Pillowman dramatizes the interrogation and torture of a horror fiction writer, Katurian, whose stories have been re-enacted in ‘real’ life without his knowledge. The audience gradually finds out that the murders are the crimes of Michal, Katurian's mentally retarded brother, who had been physically tortured by his parents in childhood, until Katurian murdered them. Upon Michal's confession, Katurian has to kill his brother to save him from the suffering and torture to come. Subsequently, it becomes clear that the two interrogators also suffer from the violent childhoods they re-enact with the violence they inflict on their suspects. It appears that all kinds of violence in the play are somehow justified, and treated in such a complex way that it becomes hard to draw boundaries between victims and perpetrators. The depiction of violence can, however, also be examined in dimensions that trigger and shape each other: the violence of the totalitarian state directed against the individual and the artist; domestic violence; the fictional violence found in Katurian's stories. Read through Slavoy Žižek's theory of violence, which also highlights the interconnected nature of its several kinds, The Pillowman can be observed to create a panoramic view of its subject. Mahinur Akşehir-Uygur is an Assistant Professor in the Department of English, Manisa Celal Bayar University in Manisa, Turkey. Her areas of interest are satirical literature, contemporary fiction, and women's literature.
‘Yae, Nae, or Dinnae Ken’: Dramatic Responses to the Scottish Referendum and Theatre Uncut
Authors: Güvenç Sıla Şenlen
Published: October 2017

In this paper Sıla Şenlen Güvenç surveys the key plays staged in the run-up to the Scottish Independence Referendum of September 2014, with special emphasis on the six Theatre Uncut plays – Rob Drummond's Party Pieces, A. J. Taudevin's The 12.57, and Lewis Hetherington's The White Lightning and the Black Stag (composed in 2013), and Davey Anderson's twin plays, Fear and Self-Loathing in West Lothian and Don't Know, Don't Care, and Kieran Hurley's Close from 2014. Written prior to the referendum and performed together for the first time at the Edinburgh Fringe Festival in 2014, these plays became even more meaningful with developing events in the United Kingdom, especially Brexit and the potential for a second independence referendum in Scotland. The plays reflect many of the issues discussed in both the ‘Yes Scotland’ and ‘Better Together’ campaigns. Sıla Şenlen Güvenç is currently Associate Professor at Ankara University's Department of English Language and Literature. Besides articles and theatre reviews on English drama, she is the author of ‘Words as Swords’: Verbal Violence as a Construction of Authority in Renaissance and Contemporary English Drama (2009) and ‘The World is a Stage, but the Play is Badly Cast’: British Political Satire in the Neo-classical Period (in Turkish, 2014).
Visualizing the Geography of the Diseases of China: Western Disease Maps from Analytical Tools to Tools of Empire, Sovereignty, and Public Health Propaganda, 1878–1929
Authors: Hanson Marta
Published: October 2017

Argument

This article analyzes for the first time the earliest western maps of diseases in China spanning fifty years from the late 1870s to the end of the 1920s. The 24 featured disease maps present a visual history of the major transformations in modern medicine from medical geography to laboratory medicine wrought on Chinese soil. These medical transformations occurred within new political formations from the Qing dynasty (1644–1911) to colonialism in East Asia (Hong Kong, Taiwan, Manchuria, Korea) and hypercolonialism within China (Tianjin, Shanghai, Amoy) as well as the new Republican Chinese nation state (1912–49). As a subgenre of persuasive graphics, physicians marshaled disease maps for various rhetorical functions within these different political contexts. Disease maps in China changed from being mostly analytical tools to functioning as tools of empire, national sovereignty, and public health propaganda legitimating new medical concepts, public health interventions, and political structures governing over human and non-human populations.
Optimal induced universal graphs for bounded-degree graphs
Authors: ALON NOGA , NENADOV RAJKO
Published: October 2017

We show that for any constant Δ ≥ 2, there exists a graph Γ withO(nΔ / 2) vertices which contains everyn-vertex graph with maximum degree Δ as an induced subgraph. For odd Δ this significantly improves the best-known earlier bound and is optimal up to a constant factor, as it is known that any such graph must have at least Ω(nΔ/2) vertices.
Optimal Collision-Avoidance Manoeuvres to Minimise Bunker Consumption under the Two-Ship Crossing Situation
Authors: Zhou Kang , Chen Jihong , Liu Xiang
Published: October 2017

This paper optimises two-ship collision-avoidance manoeuvres accounting for both collision risk and fuel use. A collision-avoidance manoeuvring optimisation model is developed to minimise fuel consumption while assuring ships' operational safety. The model can optimally determine when to begin collision-avoidance actions, how to change courses, and what rudder angles are needed. A quantitative scenario simulation is developed to illustrate the model application. The methodology can be further developed to guide practical ship collision-avoidance manoeuvring decisions made under more operational scenarios. In particular, this research can contribute to the development of computer-aided collision-avoidance operations to improve the safety and energy efficiency of maritime transportation.
Offline Calibration for MEMS Gyroscope G-sensitivity Error Coefficients Based on the Newton Iteration and Least Square Methods
Authors: Xing Li , Xiong Zhi , Liu Jian-ye , Luo Wei , Yue Ya-zhou
Published: October 2017

With the improvement of the bias instability of Micro-Electromechanical Systems (MEMS) gyroscopes, the g-sensitivity error is gradually becoming one of the more important factors that affects the dynamic accuracy of a MEMS gyroscope. Hence there is a need for correcting the g-sensitivity error. However, the traditional calibration of g-sensitivity error uses a centrifuge. The calibration conditions are harsh, the process is complex and the cost is relatively high. In this paper, a fast and simple method of g-sensitivity error calibration for MEMS gyroscopes is proposed. With respect to the bias and random noise of a MEMS gyroscope, the g-sensitivity error magnitude is relatively small and it is simultaneously coupled with the Earth's rotation rate. Therefore, in order to correct the g-sensitivity error, this work models the calibration for g-sensitivity error coefficients, designs an (8+N)-position calibration scheme, and then proposes a fitting method for g-sensitivity error coefficients based on the Newton iteration and least squares methods. Multi-group calibration experiments designed on a MEMS Inertial Measurement Unit (MEMS IMU) product demonstrate that the proposed method can calibrate g-sensitivity error coefficients and correct the g-sensitivity error effectively and simply.
Quantitative interferon-gamma responses predict future disease progression in badgers naturally infected withMycobacterium bovis
Authors: BUZDUGAN S. N. , CHAMBERS M. A. , DELAHAY R. J. , DREWE J. A.
Published: October 2017

The diagnosis and control ofMycobacterium bovisinfection (bovine tuberculosis: TB) continues to present huge challenges to the British cattle industry. A clearer understanding of the magnitude and duration of immune response toM. bovisinfection in the European badger (Meles meles) – a wildlife maintenance host – may assist with the future development of diagnostic tests, and vaccination and disease management strategies. Here, we analyse 5280 diagnostic test results from 550 live wild badgers from a naturally-infected population to investigate whether one diagnostic test (a gamma interferon release [IFNγ] assay,n= 550 tests) could be used to predict future positive results on two other tests for the same disease (a serological test [n= 2342 tests] and mycobacterial culture [n= 2388 tests]) and hence act as an indicator of likely bacterial excretion or disease progression. Badgers with the highest IFNγoptical density (OD) values were most likely to subsequently test positive on both serological and culture tests, and this effect was detectable for up to 24 months after the IFNγtest. Furthermore, the higher the original IFNγOD value, the greater the chance that a badger would subsequently test positive using serology. Relationships between IFNγtitres and mycobacterial culture results from different types of clinical sample suggest that the route of infection may affect the magnitude of immune response in badgers. These findings identify further value in the IFNγtest as a useful research tool, as it may help us to target studies at animals and groups that are most likely to succumb to more progressive disease.
Studying texts in a second language: No disadvantage in long-term recognition memory
Authors: VANDER BEKEN HELEEN , WOUMANS EVY , BRYSBAERT MARC
Published: October 2017

Despite an increase in bilingualism and the use of English as a medium of instruction, little research has been done on bilingual memory for learnt information. In a previous study, we found an L2 recall cost but equal recognition performance in L2 versus L1 when students studied short expository texts (Vander Beken & Brysbaert, 2017). In this paper, we investigate whether there is a recognition cost after a longer delay, which would indicate that the memory trace is weaker in L2. Results showed equal performance in L1 and L2, suggesting that the recall cost is either located at the production level, or that the levels-of-processing effect is mediated by language, with unaffected surface encoding leading to effectivemarginal knowledgeon the one hand, and hampered deep encoding leading to ineffective (uncued) recall. This paper also contains the Dutch vocabulary test we used for native speakers.
Foreigner talk through word reduction in native/non-native spoken interactions
Authors: RODRIGUEZ-CUADRADO SARA , BAUS CRISTINA , COSTA ALBERT
Published: October 2017

We explore the properties of foreigner talk through word reduction. Word reduction signals that the speaker is referring to the same entity as previously and should be preserved for foreigner talk. However, it leads to intelligibility loss, which works against foreigner talk. Pairs of speakers engaged in a task where native speakers talked either to a native or non-native listener. Natives talking to non-natives performed foreigner talk for duration and intensity. Duration and intensity were reduced for native and non-native listeners equally. These results suggest that word reduction is insensitive to communicative adjustments in the context of foreign talk.
Fiscal effects of the Norwegian pension reform – A micro–macro assessment
Authors: FREDRIKSEN DENNIS , HOLMØY ERLING , STRØM BIRGER , STØLEN NILS MARTIN
Published: October 2017

The main goal of the Norwegian pension reform of 2011 is to improve long run fiscal sustainability, not least through stronger labour supply incentives. We assess to what extent the reform is likely to live up to these intentions. To this end we combine a dynamic microsimulation model, which includes a complete description of the Norwegian population and the pension system, with CGE-modelling of the effects on all government revenues and expenditures. We find that the reform is likely to make a great fiscal impact in the long run, and higher employment plays an important role in this respect.
Poor perinatal growth impairs baboon aortic windkessel function
Authors: Kuo A. H. , Li J. , Li C. , Huber H. F. , Nathanielsz P. W. , Clarke G. D.
Published: October 2017

The ability of the aorta to buffer blood flow and provide diastolic perfusion (Windkessel function) is a determinant of cardiovascular health. We have reported cardiac dysfunction indicating downstream vascular abnormalities in young adult baboons who were intrauterine growth restricted (IUGR) at birth as a result of moderate maternal nutrient reduction. Using 3 T MRI, we examined IUGR offspring (eight male, eight female; 5.7 years; human equivalent 25 years) and age-matched controls (eight male, eight female; 5.6 years) to quantify distal descending aortic cross-section (AC) and distensibility (AD). ANOVA showed decreased IUGR AC/body surface area (0.9±0.05 cm2/m2v. 1.2±0.06 cm2/m2, M±s.e.m., P<0.005) and AD (1.7±0.2 v. 4.0±0.5×10−3/mmHg, P<0.005) without sex difference or group-sex interaction, suggesting intrinsic vascular pathology and impaired development persisting in adulthood. Future studies should evaluate potential consequences of these changes on coronary perfusion, afterload and blood pressure.
Associations between maternal prenatal stress, methylation changes in IGF1 and IGF2, and birth weight
Authors: Montoya-Williams D. , Quinlan J. , Clukay C. , Rodney N. C. , Kertes D. A. , Mulligan C. J.
Published: October 2017

Maternal stress has been linked to low birth weight in newborns. One potential pathway involves epigenetic changes at candidate genes that may mediate the effects of prenatal maternal stress on birth weight. This relationship has been documented in stress-related genes, such as NR3C1. There is less literature exploring the effect of stress on growth-related genes. IGF1 and IGF2 have been implicated in fetal growth and development, though via different mechanisms as IGF2 is under imprinting control. In this study, we tested for associations between prenatal stress, methylation of IGF1 and IGF2, and birth weight. A total of 24 mother–newborn dyads in the Democratic Republic of Congo were enrolled. Ethnographic interviews were conducted with mothers at delivery to gather culturally relevant war-related and chronic stressors. DNA methylation data were generated from maternal venous, cord blood and placental tissue samples. Multivariate regressions were used to test for associations between stress measures, DNA methylation and birth weight in each of the three tissue types. We found an association between IGF2 methylation in maternal blood and birth weight. Previous literature on the relationship between IGF2 methylation and birth weight has focused on methylation at known differentially methylated regions in cord blood or placental samples. Our findings indicate there may be links between the maternal epigenome and low birth weight that rely on mechanisms outside known imprinting pathways. It thus may be important to consider the effect of maternal exposures and epigenetic profiles on birth weight even in the setting of maternally imprinted genes such as IGF2.
How can Academic Context Variables Contribute to the Personal Well-Being of Higher Education Students?
Authors: Figueira Célia Palma , Marques-Pinto Alexandra , Pereira Cicero Roberto , Roberto Magda Sofia
Published: October 2017

This study analyzed the influence of perceived time pressure, role clarity, working conditions and peer social support on the personal well-being (subjective, psychological and social well-being) of higher education students, in a sample of 128 Portuguese students from the University of Lisbon. A model was proposed which predicts a negative influence of time pressure and a positive influence of role clarity, working conditions and peer social support on students’ personal well-being, throughout the academic year. Data was collected by means of a longitudinal design, at the beginning and end of the academic year, through self-report questionnaires. Structural equation models were used to analyze cross-sectional and cross-lagged relations among the variables. At cross-sectional level, results revealed a good fit to data (CFI = .928; IFI = .931; RMSEA = .060) illustrating that the perception of academic context variables was related to well-being dimensions. At longitudinal level, however, cross-lagged models did not fit so well to the data (CFI = .863; IFI = .869; RMSEA = .058) with both perceptions of time pressure (β = .167; p = .037) and role clarity (β = –.288; p = .031) significantly predicting well-being, but not in the expected direction, encouraging the accomplishment of studies to further a broader understanding of higher education students’ well-being and its predictors. Implications for higher education scholars and practitioners and suggestions for future research are discussed.
Resonant out-of-phase fluorescence microscopy and remote imaging overcome spectral limitations
Authors: Quérard Jérôme , Zhang Ruikang , Kelemen Zsolt , Plamont Marie-Aude , Xie Xiaojiang , Chouket Raja , Roemgens Insa , Korepina Yulia , Albright Samantha , Ipendey Eliane , Volovitch Michel , Sladitschek Hanna L. , Neveu Pierre , Gissot Lionel , Gautier Arnaud , Faure Jean-Denis , Croquette Vincent , Le Saux Thomas , Jullien Ludovic
Published: October 2017

We present speed out-of-phase imaging after optical modulation (OPIOM), which exploits reversible photoswitchable fluorophores as fluorescent labels and combines optimized periodic illumination with phase-sensitive detection to specifically retrieve the label signal. Speed OPIOM can extract the fluorescence emission from a targeted label in the presence of spectrally interfering fluorophores and autofluorescence. Up to four fluorescent proteins exhibiting a similar green fluorescence have been distinguished in cells either sequentially or in parallel. Speed OPIOM is compatible with imaging biological processes in real time in live cells. Finally speed OPIOM is not limited to microscopy but is relevant for remote imaging as well, in particular, under ambient light. Thus, speed OPIOM has proved to enable fast and quantitative live microscopic and remote-multiplexed fluorescence imaging of biological samples while filtering out noise, interfering fluorophores, as well as ambient light.
Growth mechanism of strongly emitting CH3NH3PbBr3 perovskite nanocrystals with a tunable bandgap
Authors: Huang He , Raith Johannes , Kershaw Stephen V. , Kalytchuk Sergii , Tomanec Ondrej , Jing Lihong , Susha Andrei S. , Zboril Radek , Rogach Andrey L.
Published: October 2017

Metal halide perovskite nanocrystals are promising materials for a diverse range of applications, such as light-emitting devices and photodetectors. We demonstrate the bandgap tunability of strongly emitting CH3NH3PbBr3 nanocrystals synthesized at both room and elevated (60 °C) temperature through the variation of the precursor and ligand concentrations. We discuss in detail the role of two ligands, oleylamine and oleic acid, in terms of the coordination of the lead precursors and the nanocrystal surface. The growth mechanism of nanocrystals is elucidated by combining the experimental results with the principles of nucleation/growth models. The proposed formation mechanism of perovskite nanocrystals will be helpful for further studies in this field and can be used as a guide to improve the synthetic methods in the future.
Single nucleus sequencing reveals spermatid chromosome fragmentation as a possible cause of maize haploid induction
Authors: Li Xiang , Meng Dexuan , Chen Shaojiang , Luo Haishan , Zhang Qinghua , Jin Weiwei , Yan Jianbing
Published: October 2017

Production of maternal haploids using a conspecific haploid inducer is routine and highly efficient in maize. However, the underlying mechanism of haploid induction (HI) is unclear. We develop a method to isolate three nuclei from a pollen grain and four microspores from a tetrad for whole-genome sequencing. A high rate of aneuploidy is observed at the three-nucleus stage (6/22 pollens) rather than at the tetrad stage (1/72 microspores) in one HI line CAU5. Frequent aneuploidy is also observed in another two inducer lines, but not in two regular lines, which implies that HI may be associated with pollen aneuploidy. We further sequence the individual embryos and endosperms of 88 maize kernels crossing between regular and inducer lines. Genome-wide elimination of the CAU5-derived chromosome is identified in eight of 81 embryos. Together, these results suggest that continuous chromosome fragmentation occurring post meiosis in the gametophyte may cause haploidy of the embryo.
Mechanism of error-free replication across benzo[a]pyrene stereoisomers by Rev1 DNA polymerase
Authors: Rechkoblit Olga , Kolbanovskiy Alexander , Landes Hannah , Geacintov Nicholas E. , Aggarwal Aneel K.
Published: October 2017

Benzo[a]pyrene (BP) is a carcinogen in cigarette smoke which, after metabolic activation, can react with the exocyclic N2 amino group of guanine to generate four stereoisomeric BP-N2-dG adducts. Rev1 is unique among translesion synthesis DNA polymerases in employing a protein-template-directed mechanism of DNA synthesis opposite undamaged and damaged guanine. Here we report high-resolution structures of yeast Rev1 with three BP-N2-dG adducts, namely the 10S (+)-trans-BP-N2-dG, 10R (+)-cis-BP-N2-dG, and 10S ( − )-cis-BP-N2-dG. Surprisingly, in all three structures, the bulky and hydrophobic BP pyrenyl residue is entirely solvent-exposed in the major groove of the DNA. This is very different from the adduct alignments hitherto observed in free or protein-bound DNA. All complexes are well poised for dCTP insertion. Our structures provide a view of cis-BP-N2-dG adducts in a DNA polymerase active site, and offer a basis for understanding error-free replication of the BP-derived stereoisomeric guanine adducts.
Real-time tracking of metal nucleation via local perturbation of hydration layers
Authors: Harniman Robert L. , Plana Daniela , Carter George H. , Bradley Kieren A. , Miles Mervyn J. , Fermín David J.
Published: October 2017

The real-time visualization of stochastic nucleation events at electrode surfaces is one of the most complex challenges in electrochemical phase formation. The early stages of metal deposition on foreign substrates are characterized by a highly dynamic process in which nanoparticles nucleate and dissolve prior to reaching a critical size for deposition and growth. Here, high-speed non-contact lateral molecular force microscopy employing vertically oriented probes is utilized to explore the evolution of hydration layers at electrode surfaces with the unprecedented spatiotemporal resolution, and extremely low probe-surface interaction forces required to avoid disruption or shielding the critical nucleus formation. To the best of our knowledge, stochastic nucleation events of nanoscale copper deposits are visualized in real time for the first time and a highly dynamic topographic environment prior to the formation of critical nuclei is unveiled, featuring formation/re-dissolution of nuclei, two-dimensional aggregation and nuclei growth.
NOX4 functions as a mitochondrial energetic sensor coupling cancer metabolic reprogramming to drug resistance
Authors: Shanmugasundaram Karthigayan , Nayak Bijaya K. , Friedrichs William E. , Kaushik Dharam , Rodriguez Ronald , Block Karen
Published: October 2017

The molecular mechanisms that couple glycolysis to cancer drug resistance remain unclear. Here we identify an ATP-binding motif within the NADPH oxidase isoform, NOX4, and show that ATP directly binds and negatively regulates NOX4 activity. We find that NOX4 localizes to the inner mitochondria membrane and that subcellular redistribution of ATP levels from the mitochondria act as an allosteric switch to activate NOX4. We provide evidence that NOX4-derived reactive oxygen species (ROS) inhibits P300/CBP-associated factor (PCAF)-dependent acetylation and lysosomal degradation of the pyruvate kinase-M2 isoform (PKM2). Finally, we show that NOX4 silencing, through PKM2, sensitizes cultured and ex vivo freshly isolated human-renal carcinoma cells to drug-induced cell death in xenograft models and ex vivo cultures. These findings highlight yet unidentified insights into the molecular events driving cancer evasive resistance and suggest modulation of ATP levels together with cytotoxic drugs could overcome drug-resistance in glycolytic cancers.
Mapping the ultrafast flow of harvested solar energy in living photosynthetic cells
Authors: Dahlberg Peter D. , Ting Po-Chieh , Massey Sara C. , Allodi Marco A. , Martin Elizabeth C. , Hunter C. Neil , Engel Gregory S.
Published: October 2017

Photosynthesis transfers energy efficiently through a series of antenna complexes to the reaction center where charge separation occurs. Energy transfer in vivo is primarily monitored by measuring fluorescence signals from the small fraction of excitations that fail to result in charge separation. Here, we use two-dimensional electronic spectroscopy to follow the entire energy transfer process in a thriving culture of the purple bacteria,Rhodobacter sphaeroides. By removing contributions from scattered light, we extract the dynamics of energy transfer through the dense network of antenna complexes and into the reaction center. Simulations demonstrate that these dynamics constrain the membrane organization into small pools of core antenna complexes that rapidly trap energy absorbed by surrounding peripheral antenna complexes. The rapid trapping and limited back transfer of these excitations lead to transfer efficiencies of 83% and a small functional light-harvesting unit.
Gate-controlled reversible rectifying behaviour in tunnel contacted atomically-thin MoS2 transistor
Authors: Li Xiao-Xi , Fan Zhi-Qiang , Liu Pei-Zhi , Chen Mao-Lin , Liu Xin , Jia Chuan-Kun , Sun Dong-Ming , Jiang Xiang-Wei , Han Zheng , Bouchiat Vincent , Guo Jun-Jie , Chen Jian-Hao , Zhang Zhi-Dong
Published: October 2017

Atomically thin two-dimensional semiconducting materials integrated into van der Waals heterostructures have enabled architectures that hold great promise for next generation nanoelectronics. However, challenges still remain to enable their applications as compliant materials for integration in logic devices. Here, we devise a reverted stacking technique to intercalate a wrinkle-free boron nitride tunnel layer between MoS2 channel and source drain electrodes. Vertical tunnelling of electrons therefore makes it possible to suppress the Schottky barriers and Fermi level pinning, leading to homogeneous gate-control of the channel chemical potential across the bandgap edges. The observed features of ambipolar pn to np diode, which can be reversibly gate tuned, paves the way for future logic applications and high performance switches based on atomically thin semiconducting channel.
Full-gap superconductivity in spin-polarised surface states of topological semimetal β-PdBi2
Authors: Iwaya K. , Kohsaka Y. , Okawa K. , Machida T. , Bahramy M. S. , Hanaguri T. , Sasagawa T.
Published: October 2017

A bulk superconductor possessing a topological surface state at the Fermi level is a promising system to realise long-sought topological superconductivity. Although several candidate materials have been proposed, experimental demonstrations concurrently exploring spin textures and superconductivity at the surface have remained elusive. Here we perform spectroscopic-imaging scanning tunnelling microscopy on the centrosymmetric superconductor β-PdBi2 that hosts a topological surface state. By combining first-principles electronic-structure calculations and quasiparticle interference experiments, we determine the spin textures at the surface, and show not only the topological surface state but also all other surface bands exhibit spin polarisations parallel to the surface. We find that the superconducting gap fully opens in all the spin-polarised surface states. This behaviour is consistent with a possible spin-triplet order parameter expected for such in-plane spin textures, but the observed superconducting gap amplitude is comparable to that of the bulk, suggesting that the spin-singlet component is predominant in β-PdBi2.
Elevated olivine weathering rates and sulfate formation at cryogenic temperatures on Mars
Authors: Niles Paul B. , Michalski Joseph , Ming Douglas W. , Golden D. C.
Published: October 2017

Large Hesperian-aged (~3.7 Ga) layered deposits of sulfate-rich sediments in the equatorial regions of Mars have been suggested to be evidence for ephemeral playa environments. But early Mars may not have been warm enough to support conditions similar to what occurs in arid environments on Earth. Instead cold, icy environments may have been widespread. Under cryogenic conditions sulfate formation might be blocked, since kinetics of silicate weathering are typically strongly retarded at temperatures well below 0 °C. But cryo-concentration of acidic solutions may counteract the slow kinetics. Here we show that cryo-concentrated acidic brines rapidly chemically weather olivine minerals and form sulfate minerals at temperatures as low as −60 °C. These experimental results demonstrate the viability of sulfate formation under current Martian conditions, even in the polar regions. An ice-hosted sedimentation and weathering model may provide a compelling description of the origin of large Hesperian-aged layered sulfate deposits on Mars.
Super-formable pure magnesium at room temperature
Authors: Zeng Zhuoran , Nie Jian-Feng , Xu Shi-Wei , H. J. Davies Chris , Birbilis Nick
Published: October 2017

Magnesium, the lightest structural metal, is difficult to form at room temperature due to an insufficient number of deformation modes imposed by its hexagonal structure and a strong texture developed during thermomechanical processes. Although appropriate alloying additions can weaken the texture, formability improvement is limited because alloying additions do not fundamentally alter deformation modes. Here we show that magnesium can become super-formable at room temperature without alloying. Despite possessing a strong texture, magnesium can be cold rolled to a strain at least eight times that possible in conventional processing. The resultant cold-rolled sheet can be further formed without cracking due to grain size reduction to the order of one micron and inter-granular mechanisms becoming dominant, rather than the usual slip and twinning. These findings provide a pathway for developing highly formable products from magnesium and other hexagonal metals that are traditionally difficult to form at room temperature.