bluuebunny/crossref_metadata_2025 huggingface dataset:
Near peer integrated teaching for final year medical students
Authors: Fulford Laurence , Gunn Victoria , Davies Gregory , Evans Claire , Raza Tanzeem , Vassallo Michael
Published: February 2016

Introduction Medical students preparing for final exams need practical and theoretical knowledge. We evaluated a junior doctor led integrated programme delivering theoretical and practical teaching.

Methods An 8-week junior-doctor led teaching programme was set up for final year medical students. Theory, OSCE and bedside teaching on selected weekly clinical themes were run. Satisfaction was evaluated using a questionnaire survey.

Results Almost all agreed that the programme was useful and that an integrated approach to teaching was more beneficial than separate and unrelated lectures and practical teaching. The majority agreed that theory sessions and practical sessions had improved their confidence for finals and agreed they felt more prepared for work as a doctor. Most agreed that the Facebook® group provided an easily accessible platform for communication and sharing learning resources. Some comments, however, highlighted limitations particularly in the ability to answer difficult questions.

Conclusion Integrated teaching by junior doctors in small groups appeared to be an efficient teaching method (for theoretical and clinical skills) for medical students, improving their confidence for finals and life as a doctor and provided useful opportunities for junior doctors to develop as clinical teachers. This can be a useful blueprint for other hospitals.
RETRACTED: Comparison between the traditional non‐guided and a novel ultrasound‐guided technique for office fitting of intrauterine contraceptive devices
Authors: Elsedeek Mervat S.
Published: February 2016

Objective

To investigate a novel method for in‐office fitting of intrauterine contraceptive devices (IUCDs) by comparing it to the traditional non‐guided technique.

Methods

A prospective cohort study comparing the application of intrauterine contraceptives was conducted between January 1, 2013 and January 31, 2015 at a university contraception clinic, in Alexandria, Egypt. Patients aged 20–45 years who were parous, had previously undergone vaginal or abdominal deliveries, and were requesting device insertion were included. Patients were randomly assigned to have devices fitted using the non‐guided approach, with vaginal ultrasonography to plan and confirm device placement, or by the abdominal ultrasonography‐guided technique. The primary outcomes were successful IUCD insertion and ideal device position 1 week after insertion. Participants, counselors, and data analysts were masked to treatment assignments.

Results

Analyses included 40 patients in each treatment arm. Successful fitting was achieved in 32 (80%) patients in the non‐guided arm and 39 (98%) patients in the ultrasonography‐guided arm (P = 0.04). Ideal placement was achieved in 38 (95%) patients in the ultrasonography‐guided arm compared with 27 (68%) patients in the non‐guided arm (P = 0.02).

Conclusion

Ultrasonography‐guided IUCD insertion demonstrated improved success and fitting accuracy in comparison with a traditional, non‐guided approach.

ANZCTR trial ID: ACTRN12615000526572
Longitudinal decline in mild‐to‐moderate Alzheimer's disease: Analyses of placebo data from clinical trials
Authors: Thomas Ronald G. , Albert Marilyn , Petersen Ronald C. , Aisen Paul S.
Published: February 2016

Introduction

Accurate estimates of cognitive and clinical decline rates are essential to the design of clinical trials in Alzheimer's disease (AD) dementia.

Methods

To investigate the trajectories of individuals enrolled in therapeutic trials in mild‐to‐moderate AD, we analyzed the placebo arm data from 20 clinical trials including over 4500 subjects. We analyzed decline as measured by two cognitive instruments, the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAScog) and the Mini‐Mental State Examination, and one clinical rating scale, the Clinical Dementia Rating Sum of Boxes.

Results

Trajectories were generally similar across trials and nearly linear. Greater cognitive impairment at baseline, younger age, and greater education were associated with increased rate of cognitive decline. Effect sizes for the ADAScog were generated as a function of population characteristics.

Discussion

These data will inform the design of future studies of potential disease‐modifying therapies for mild‐to‐moderate AD dementia.
The contact line of an evaporating droplet over a solid wedge and the pinned–unpinned transition
Authors: Hong Seok Hyun , Fontelos Marco A. , Hwang Hyung Ju
Published: February 2016

We compute the equilibrium contact angles for an evaporating droplet whose contact line lies over a solid wedge. The stability of the liquid interface is also considered and an integro-differential equation for small perturbations is deduced. The analysis of this equation yields criteria for stability and instability of the contact line, where the instability represents transition from the pinned to unpinned contact line representative of stick–slip motion.
Effects of replacing meat with soyabean in the diet on sex hormone concentrations in healthy adult males
Authors: Habito Raymundo C. , Montalto Joseph , Leslie Eva , Ball Madeleine J.
Published: February 2016

A randomised crossover dietary intervention study was performed to evaluate the effects of replacing meat protein in the diet with a soyabean product, tofu, on blood concentrations of testosterone, dihydrotestosterone, androstanediol glucuronide, oestradiol, sex hormone-binding globulin (SHBG), and the free androgen index (total testosterone concentration/SHBG concentration×100; FAI). Forty-two healthy adult males aged 35–62 years were studied. Diets were isoenergetic, with either 150 g lean meat or 290 g tofu daily providing an equivalent amount of macronutrients, with only the source of protein differing between the two diets. Each diet lasted for 4 weeks, with a 2-week interval between interventions. Fasting blood samples were taken between 07.00 and 09.30 hours. Urinary excretion of genistein and daidzein was significantly higher after the tofu diet (P<0·001). Blood concentrations of sex hormones did not differ after the two diets, but the mean testosterone:oestradiol value was 10 % higher (P=0·06) after the meat diet. SHBG was 3 % higher (P= 0·07), whereas the FAI was 7 % lower (P=0·06), after the tofu diet compared with the meat diet. There was a significant correlation between the difference in SHBG and testosterone:oestradiol and weight change. Adjusting for weight change revealed SHBG to be 8·8 % higher on the tofu diet (mean difference 3 (95 % CI 0·7, 5·2) nmol/l; (P=0·01) and testosterone:oestradiol to be significantly lower, P=0·049). Thus, replacement of meat protein with soyabean protein, as tofu, may have a minor effect on biologically-active sex hormones, which could influence prostate cancer risk. However, other factors or mechanisms may also be responsible for the different incidence rates in men on different diets.
Mineral riches: a route to Greenland's independence?
Authors: Taagholt Jørgen , Brooks Kent
Published: February 2016

This paper presents a brief history of Greenland which sets the scene for unprecedented recent developments, both materially and politically. After the war, in 1953, the political status of Greenland was changed from colony to an integral part of Denmark. Greenland gained home rule [Hjemmestyre] in 1979 and greater devolution to self rule [Selvstyre] in 2009. The population is becoming centralised, increasingly resembling consumer societies worldwide. In recent years the economy has been mainly based upon fish and mining, although at present there is no active mine and the economy is declining, making the country increasingly dependent on subsidies from Denmark. The former president recently predicted that Greenland would leave Denmark within her life-time, a view based upon her vision of the development of a rich mining industry. Additionally she established a reconciliation committee to examine supposed ill-treatment by Denmark. The present situation and the unrealistic expectations of huge production of different minerals are discussed based upon accepted predictions of mineral resources, world market prices, logistic problems (lack of infrastructure and tiny population) and environmental concerns. During the past year, a more realistic and less confrontational debate on the relations between Denmark and Greenland has been evident.
Honor and War
Authors: Dafoe Allan , Caughey Devin
Published: February 2016

Reputation has long been considered central to international relations, but unobservability, strategic selection, and endogeneity have handicapped quantitative research. A rare source of haphazard variation in the cultural origins of leaders-the fact that one-third of US presidents were raised in the American South, a well-studied example of a culture of honor-provides an opportunity to identify the effects of heightened concern for reputation for resolve. A formal theory that yields several testable predictions while accounting for unobserved selection into disputes is offered. The theory is illustrated through a comparison of presidents John F. Kennedy and Lyndon B. Johnson and systematically tested using matching, permutation inference, and the nonparametric combination of tests. Interstate conflicts under Southern presidents are shown to be twice as likely to involve uses of force, last on average twice as long, and are three times more likely to end in victory for the United States than disputes under non-Southern presidents. Other characteristics of Southern presidencies do not seem able to account for this pattern of results. Theresults provide evidence that concern for reputation is an important cause of interstate conflict behavior.
Appropriation and Subversion
Authors: Lankina Tomila V. , Libman Alexander , Obydenkova Anastassia
Published: February 2016

Twenty-five years after the collapse of communism in Europe, few scholars disagree that the past continues to shape the democratic trajectories of postcommunist states. Precommunist education has featured prominently in this literature’s bundle of “good” legacies because it ostensibly helped foster resistance to communism. The authors propose a differentcausal mechanism—appropriation and subversion—that challenges the linearity of the above assumptions by analyzing the effects of precommunist literacy on patterns of Communist Party recruitment in Russia’s regions. Rather than regarding precommunist education as a source of latent resistance to communism, the authorshighlight the Leninist regime’s successful appropriation of the more literate strata of the precommunist orders, in the process subverting the past democratic edge of the hitherto comparatively more developed areas. The linear regression analysis of author—assembled statistics from the first Russian imperial census of 1897 supports prior research: precommunist literacy has a strong positive association with postcommunist democratic outcomes. Nevertheless, in pursuing causal mediation analysis, the authors find, in addition, that the above effect is mediated by Communist Party saturation in Russia’s regions. Party functionaries were likely to be drawn from areas that had been comparatively more literate in tsarist times, andparty saturation in turn had a dampening effect on the otherwise positive effects of precommunist education on postcommunist democracy.
SPECIFICATION TESTS FOR MULTIPLICATIVE ERROR MODELS
Authors: Perera Indeewara , Silvapulle Mervyn J.
Published: February 2016

The family of multiplicative error models is important for studying non-negative variables such as realized volatility, trading volume, and duration between consecutive financial transactions. Methods are developed for testing the parametric specification of a multiplicative error model, which consists of separate parametric models for the conditional mean and the error distribution. The same method can also be used for testing the specification of the error distribution provided the conditional mean is correctly specified. A bootstrap method is proposed for computing the p-values of the tests and is shown to be consistent. The proposed tests have nontrivial asymptotic power against a class of O(n−1/2)-local alternatives. The tests performed well in a simulation study, and they are illustrated using a data example on realized volatility.
Cats on the Couch: The Experimental Production of Animal Neurosis
Authors: Winter Alison
Published: February 2016

Argument

In the 1940s–50s, one of the most central questions in psychological research related to the nature of neurosis. In the final years of the Second World War and the following decade, neurosis became one of the most prominent psychiatric disorders, afflicting a high proportion of military casualties and veterans. The condition became central to the concerns of several psychological fields, from psychoanalysis to Pavlovian psychology. This paper reconstructs the efforts of Chicago psychiatrist Jules Masserman to study neurosis in the laboratory during the 1940s and 1950s. Masserman used Pavlovian techniques in a bid to subject this central psychoanalytic subject to disciplined scientific experimentation. More generally, his project was an effort to bolster the legitimacy of psychoanalysis as a human science by articulating a convergence of psychoanalytic categories across multiple species. Masserman sought to orchestrate a convergence of psychological knowledge between fields that were often taken to be irreconcilable. A central focus of this paper is the role of moving images in this project, not only as a means of recording experimental data but also as a rhetorical device. The paper argues that for Masserman film played an important role in enabling scientific observers (and then subsequent viewers) to see agency and emotion in the animals they observed.
Naming the Ethological Subject
Authors: Benson Etienne S.
Published: February 2016

Argument

In recent decades, through the work of Jane Goodall and other ethologists, the practice of giving personal names to nonhuman animals who are the subjects of scientific research has become associated with claims about animal personhood and scientific objectivity. While critics argue that such naming practices predispose the researcher toward anthropomorphism, supporters suggest that it sensitizes the researcher to individual differences and social relations. Both critics and supporters agree that naming tends to be associated with the recognition of individual animal rights. The history of the naming of research animals since the late nineteenth century shows, however, that the practice has served a variety of purposes, most of which have raised few ethical or epistemological concerns. Names have been used to identify research animals who play dual roles as pets, workers, or patients, to enhance their market value, and to facilitate their identification in the field. The multifaceted history of naming suggests both that the use of personal names by Goodall and others is less of a radical break with previous practices than it might first appear to be and that the use of personal names to recognize the individuality, sentience, or rights of nonhuman animals faces inherent limits and contradictions.
Maternal physiological dysregulation while parenting poses risk for infant attachment disorganization and behavior problems
Authors: Leerkes Esther M. , Su Jinni , Calkins Susan D. , O'Brien Marion , Supple Andrew J.
Published: February 2016

The extent to which indices of maternal physiological arousal (skin conductance augmentation) and regulation (vagal withdrawal) while parenting predict infant attachment disorganization and behavior problems directly or indirectly via maternal sensitivity was examined in a sample of 259 mothers and their infants. Two covariates, maternal self-reported emotional risk and Adult Attachment Interview attachment coherence were assessed prenatally. Mothers' physiological arousal and regulation were measured during parenting tasks when infants were 6 months old. Maternal sensitivity was observed during distress-eliciting tasks when infants were 6 and 14 months old, and an average sensitivity score was calculated. Attachment disorganization was observed during the Strange Situation when infants were 14 months old, and mothers reported on infants' behavior problems when infants were 27 months old. Over and above covariates, mothers' arousal and regulation while parenting interacted to predict infant attachment disorganization and behavior problems such that maternal arousal was associated with higher attachment disorganization and behavior problems when maternal regulation was low but not when maternal regulation was high. This effect was direct and not explained by maternal sensitivity. The results suggest that maternal physiological dysregulation while parenting places infants at risk for psychopathology.
Executive control mechanisms in bilingualism: Beyond speed of processing
Authors: MARTON KLARA , GORAL MIRA , CAMPANELLI LUCA , YOON JUNGMEE , OBLER LORAINE K.
Published: February 2016

The question of interest in this study was whether bilingual individuals show superior executive control compared to monolingual participants. Findings are mixed, with studies showing advantage, disadvantage, or no difference between bilingual and monolingual speakers. In this study, we used different experimental conditions to examine implicit learning, resistance to interference, monitoring, and switching, independently. In addition, we matched our monolingual and bilingual participants on baseline response time. Bilingual participants demonstrated faster implicit learning, greater resistance to interference, more efficient switching compared to monolingual participants. The groups did not differ in monitoring. In conclusion, depending on task complexity and on the target executive control component, there are different patterns of bilingual advantage, beyond the global faster processing speed documented in previous studies. Bilingual young adults showed more efficient adjustments of the cognitive system in response to changes in task demands.
A tale of two worlds: a (very) select overview of socio-legal studies in Belgium
Authors: Parmentier Stephan
Published: February 2016

Socio-legal studies in Belgium represent a diverse patchwork of many topics studied from many angles. This paper first presents a brief historical account of socio-legal studies and their organisation, in the north and south of the country. It has no ambition to give a full overview of socio-legal studies in Belgium, let alone be exhaustive. It merely focuses on the content and features of two topics that have constituted major strands of research over the last thirty years: courts and dispute processing, and public opinion about law and justice. It ends with some reflections on the nature of Belgian socio-legal research, as well as some recommendations on future orientations.
Is cheaper better? Public and private lawyers before criminal courts in Mexico City
Authors: Fondevilla Gustavo , Reyes Rodrigo Meneses
Published: February 2016

This paper aims to conduct a descriptive analysis of a total of 2,172 semi-structured interviews with sentenced inmates in Mexico City during 2002–2008 in order to explain how public legal defence works, how this service is evaluated by the inmates who took part in the interviews, and how the traditional division between public and private services constitutes an important distinction in the way in which criminals interact with, and are processed by, the legal system. Our findings suggest that, in the case of Mexico City: (i) to be tried by a public defender not only implies that the person accused holds a bigger chance of getting a softer sentence than those defended by private lawyers; but also, (ii) that the population will have a better perception of the justice process.
Iron availability shapes the evolution of bacteriocin resistance in Pseudomonas aeruginosa
Authors: Inglis R Fredrik , Scanlan Pauline , Buckling Angus
Published: February 2016

The evolution of bacterial resistance to conventional antimicrobials is a widely documented phenomenon with gravely important consequences for public health. However, bacteria also produce a vast repertoire of natural antimicrobials, presumably in order to kill competing species. Bacteriocins are a common class of protein-based antimicrobials that have been shown to have an important role in the ecology and evolution of bacterial communities. Relative to the evolution of antibiotic resistance, little is known about how novel resistance to these toxic compounds evolves. In this study, we present results illustrating that, although resistance is able to evolve, it remains critically dependent on the environmental context. Resistance to bacteriocins, in particular the pyocin S2, evolves readily when iron is present but less so when iron is limiting, because the receptor for this pyocin is also required for iron uptake during iron limitation. This suggests that although resistance to bacteriocins can easily evolve, environmental conditions will determine how and when resistance occurs.
Stimulated Raman adiabatic passage in a three-level superconducting circuit
Authors: Kumar K. S. , Vepsäläinen A. , Danilin S. , Paraoanu G. S.
Published: February 2016

The adiabatic manipulation of quantum states is a powerful technique that opened up new directions in quantum engineering—enabling tests of fundamental concepts such as geometrical phases and topological transitions, and holding the promise of alternative models of quantum computation. Here we benchmark the stimulated Raman adiabatic passage for circuit quantum electrodynamics by employing the first three levels of a transmon qubit. In this ladder configuration, we demonstrate a population transfer efficiency >80% between the ground state and the second excited state using two adiabatic Gaussian-shaped control microwave pulses. By doing quantum tomography at successive moments during the Raman pulses, we investigate the transfer of the population in time domain. Furthermore, we show that this protocol can be reversed by applying a third adiabatic pulse, we study a hybrid nondiabatic–adiabatic sequence, and we present experimental results for a quasi-degenerate intermediate level.
Aharonov–Bohm oscillations in Dirac semimetal Cd3As2 nanowires
Authors: Wang Li-Xian , Li Cai-Zhen , Yu Da-Peng , Liao Zhi-Min
Published: February 2016

Three-dimensional Dirac semimetals, three-dimensional analogues of graphene, are unusual quantum materials with massless Dirac fermions, which can be further converted to Weyl fermions by breaking time reversal or inversion symmetry. Topological surface states with Fermi arcs are predicted on the surface and have been observed by angle-resolved photoemission spectroscopy experiments. Although the exotic transport properties of the bulk Dirac cones have been demonstrated, it is still a challenge to reveal the surface states via transport measurements due to the highly conductive bulk states. Here, we show Aharonov–Bohm oscillations in individual single-crystal Cd3As2 nanowires with low carrier concentration and large surface-to-volume ratio, providing transport evidence of the surface state in three-dimensional Dirac semimetals. Moreover, the quantum transport can be modulated by tuning the Fermi level using a gate voltage, enabling a deeper understanding of the rich physics residing in Dirac semimetals.
Vector-free transmission and persistence of Japanese encephalitis virus in pigs
Authors: Ricklin Meret E. , García-Nicolás Obdulio , Brechbühl Daniel , Python Sylvie , Zumkehr Beatrice , Nougairede Antoine , Charrel Remi N. , Posthaus Horst , Oevermann Anna , Summerfield Artur
Published: February 2016

Japanese encephalitis virus (JEV), a main cause of severe viral encephalitis in humans, has a complex ecology, composed of a cycle involving primarily waterbirds and mosquitoes, as well as a cycle involving pigs as amplifying hosts. To date, JEV transmission has been exclusively described as being mosquito-mediated. Here we demonstrate that JEV can be transmitted between pigs in the absence of arthropod vectors. Pigs shed virus in oronasal secretions and are highly susceptible to oronasal infection. Clinical symptoms, virus tropism and central nervous system histological lesions are similar in pigs infected through needle, contact or oronasal inoculation. In all cases, a particularly important site of replication are the tonsils, in which JEV is found to persist for at least 25 days despite the presence of high levels of neutralizing antibodies. Our findings could have a major impact on the ecology of JEV in temperate regions with short mosquito seasons.
Three-Dimensional Characterization of Mechanical Interactions between Endothelial Cells and Extracellular Matrix during Angiogenic Sprouting
Authors: Du Yue , Herath Sahan C. B. , Wang Qing-guo , Wang Dong-an , Asada H. Harry , Chen Peter C. Y.
Published: February 2016

We studied the three-dimensional cell-extracellular matrix interactions of endothelial cells that form multicellular structures called sprouts. We analyzed the data collected in-situ from angiogenic sprouting experiments and identified the differentiated interaction behavior exhibited by the tip and stalk cells. Moreover, our analysis of the tip cell lamellipodia revealed the diversity in their interaction behavior under certain conditions (e.g., when the heading of a sprout is switched approximately between the long-axis direction of two different lamellipodia). This study marks the first time that new characteristics of such interactions have been identified with shape changes in the sprouts and the associated rearrangements of collagen fibers. Clear illustrations of such changes are depicted in three-dimensional views.
Diversity between mammalian tolloid proteinases: Oligomerisation and non-catalytic domains influence activity and specificity
Authors: Bayley Christopher P. , Ruiz Nivia Hilda D. , Dajani Rana , Jowitt Thomas A. , Collins Richard F. , Rada Heather , Bird Louise E. , Baldock Clair
Published: February 2016

The mammalian tolloid family of metalloproteinases is essential for tissue patterning and extracellular matrix assembly. The four members of the family: bone morphogenetic protein-1 (BMP-1), mammalian tolloid (mTLD), tolloid-like (TLL)-1 and TLL-2 differ in their substrate specificity and activity levels, despite sharing similar domain organization. We have previously described a model of substrate exclusion by dimerisation to explain differences in the activities of monomeric BMP-1 and dimers of mTLD and TLL-1. Here we show that TLL-2, the least active member of the tolloid family, is predominantly monomeric in solution, therefore it appears unlikely that substrate exclusion via dimerisation is a mechanism for regulating TLL-2 activity. X-ray scattering and electron microscopy structural and biophysical analyses reveal an elongated shape for the monomer and flexibility in the absence of calcium. Furthermore, we show that TLL-2 can cleave chordin in vitro, similar to other mammalian tolloids, but truncated forms of TLL-2 mimicking BMP-1 are unable to cleave chordin. However, both the N- and C-terminal non-catalytic domains from all mammalian tolloids bind chordin with high affinity. The mechanisms underlying substrate specificity and activity in the tolloid family are complex with variation between family members and depend on both multimerisation and substrate interaction.
Isolation of a recombinant antibody specific for a surface marker of the corneal endothelium by phage display
Authors: Dorfmueller Simone , Tan Hwee Ching , Ngoh Zi Xian , Toh Kai Yee , Peh Gary , Ang Heng-Pei , Seah Xin-Yi , Chin Angela , Choo Andre , Mehta Jodhbir S. , Sun William
Published: February 2016

Cell surface antigens are important targets for monoclonal antibodies, but they are often difficult to work with due to their association with the cell membrane. Phage display is a versatile technique that can be applied to generate binders against difficult targets. Here we used antibody phage display to isolate a binder for a rare and specialized cell, the human corneal endothelial cell. The human corneal endothelium is a medically important cell layer; defects in this layer account for about half of all corneal transplants. Despite its importance, no specific antigens have been found to mark this cell type. By panning a phage library directly on human corneal endothelial cells, we isolated an antibody that bound to these cells and not the other types of corneal cells. Subsequently, we identified the antibody’s putative target to be CD166 by immunoprecipitation and mass spectrometry. This approach can be used to isolate antibodies against other poorly-characterized cell types, such as stem cells or cancer cells, without any prior knowledge of their discriminating markers.
Comparative transcriptome and proteome analysis to reveal the biosynthesis of gold nanoparticles in Arabidopsis
Authors: Tiwari Manish , Krishnamurthy Sneha , Shukla Devesh , Kiiskila Jeffrey , Jain Ajay , Datta Rupali , Sharma Nilesh , Sahi Shivendra V.
Published: February 2016

A large number of plants have been tested and exploited in search of a green chemistry approach for the fabrication of gold or other precious metal nanomaterials. Despite the potential of plant based methods, very little is known about the underlying biochemical reactions and genes involved in the biotransformation mechanism of AuCl4 into gold nanoparticles (AuNPs). In this research, we thus focused on studying the effect of Au on growth and nanoparticles formation by analyses of transcriptome, proteome and ionome shift in Arabidopsis. Au exposure favored the growth of Arabidopsis seedling and induced formation of nanoparticles in root and shoot, as indicated by optical and hyperspectral imaging. Root transcriptome analysis demonstrated the differential expression of the members of WRKY, MYB and BHLH gene families, which are involved in the Fe and other essential metals homeostasis. The proteome analysis revealed that Glutathione S-transferases were induced in the shoot and suggested its potential role in the biosynthesis AuNPs. This study also demonstrated the role of plant hormone auxin in determining the Au induced root system architecture. This is the first study using an integrated approach to understand the in planta biotransformation of KAuCl4 into AuNPs.
Entanglement dynamics of Nitrogen-vacancy centers spin ensembles coupled to a superconducting resonator
Authors: Liu Yimin , You Jiabin , Hou Qizhe
Published: February 2016

Exploration of macroscopic quantum entanglement is of great interest in both fundamental science and practical application. We investigate a hybrid quantum system that consists of two nitrogen-vacancy centers ensembles (NVE) coupled to a superconducting coplanar waveguide resonator (CPWR). The collective magnetic coupling between the NVE and the CPWR is employed to generate macroscopic entanglement between the NVEs, where the CPWR acts as the quantum bus. We find that, this NVE-CPWR hybrid system behaves as a system of three coupled harmonic oscillators and the excitation prepared initially in the CPWR can be distributed into these two NVEs. In the nondissipative case, the entanglement of NVEs oscillates periodically and the maximal entanglement always keeps unity if the CPWR is initially prepared in the odd coherent state. Considering the dissipative effect from the CPWR and NVEs, the amount of entanglement between these two NVEs strongly depends on the initial state of the CPWR and the maximal entanglement can be tuned by adjusting the initial states of the total system. The experimental feasibility and challenge with currently available technology are discussed.
Floating mechanism of a small liquid marble
Authors: Ooi Chin Hong , Plackowski Chris , Nguyen Anh V. , Vadivelu Raja K. , John James A. St. , Dao Dzung Viet , Nguyen Nam-Trung
Published: February 2016

Flotation of small solid objects and liquid droplets on water is critical to natural and industrial activities. This paper reports the floating mechanism of liquid marbles, or liquid droplets coated with hydrophobic microparticles. We used X-ray computed tomography (XCT) to acquire cross-sectional images of the floating liquid marble and interface between the different phases. We then analysed the shape of the liquid marble and the angles at the three-phase contact line (TPCL). We found that the small floating liquid marbles follow the mechanism governing the flotation of solid objects in terms of surface tension forces. However, the contact angles formed and deformation of the liquid marble resemble that of a sessile liquid droplet on a thin, elastic solid. For small liquid marbles, the contact angle varies with volume due to the deformability of the interface.
Facile One-pot Transformation of Iron Oxides from Fe2O3 Nanoparticles to Nanostructured Fe3O4@C Core-Shell Composites via Combustion Waves
Authors: Shin Jungho , Lee Kang Yeol , Yeo Taehan , Choi Wonjoon
Published: February 2016

The development of a low-cost, fast, and large-scale process for the synthesis and manipulation of nanostructured metal oxides is essential for incorporating materials with diverse practical applications. Herein, we present a facile one-pot synthesis method using combustion waves that simultaneously achieves fast reduction and direct formation of carbon coating layers on metal oxide nanostructures. Hybrid composites of Fe2O3nanoparticles and nitrocellulose on the cm scale were fabricated by a wet impregnation process. We demonstrated that self-propagating combustion waves along interfacial boundaries between the surface of the metal oxide and the chemical fuels enabled the release of oxygen from Fe2O3. This accelerated reaction directly transformed Fe2O3into Fe3O4nanostructures. The distinctive color change from reddish-brown Fe2O3to dark-gray Fe3O4confirmed the transition of oxidation states and the change in the fundamental properties of the material. Furthermore, it simultaneously formed carbon layers of 5–20 nm thickness coating the surfaces of the resulting Fe3O4nanoparticles, which may aid in maintaining the nanostructures and improving the conductivity of the composites. This newly developed use of combustion waves in hybridized nanostructures may permit the precise manipulation of the chemical compositions of other metal oxide nanostructures, as well as the formation of organic/inorganic hybrid nanostructures.
Visualizing Trimming Dependence of Biodistribution and Kinetics with Homo- and Heterogeneous N-Glycoclusters on Fluorescent Albumin
Authors: Ogura Akihiro , Tahara Tsuyoshi , Nozaki Satoshi , Morimoto Koji , Kizuka Yasuhiko , Kitazume Shinobu , Hara Mitsuko , Kojima Soichi , Onoe Hirotaka , Kurbangalieva Almira , Taniguchi Naoyuki , Watanabe Yasuyoshi , Tanaka Katsunori
Published: February 2016

A series of N-glycans, each sequentially trimmed from biantennary sialoglycans, were homo- or heterogeneously clustered efficiently on fluorescent albumin using a method that combined strain-promoted alkyne-azide cyclization and 6π-azaelectrocyclization. Noninvasive in vivo kinetics and dissection analysis revealed, for the first time, a glycan-dependent shift from urinary to gall bladder excretion mediated by sequential trimming of non-reducing end sialic acids. N-glycoalbumins that were trimmed further, in particular, GlcNAc- and hybrid biantennary-terminated congeners, were selectively taken up by sinusoidal endothelial and stellate cells in the liver, which are critical for diagnosis and treatment of liver fibrillation. Our glycocluster strategy can not only reveal the previously unexplored extracellular functions of N-glycan trimming, but will be classified as the newly emerging glycoprobes for diagnostic and therapeutic applications.
Living biointerfaces based on non-pathogenic bacteria support stem cell differentiation
Authors: Hay Jake J. , Rodrigo-Navarro Aleixandre , Hassi Karoliina , Moulisova Vladimira , Dalby Matthew J. , Salmeron-Sanchez Manuel
Published: February 2016

Lactococcus lactis, a non-pathogenic bacteria, has been genetically engineered to express the III7–10fragment of human fibronectin as a membrane protein. The engineeredL. lactisis able to develop biofilms on different surfaces (such as glass and synthetic polymers) and serves as a long-term substrate for mammalian cell culture, specifically human mesenchymal stem cells (hMSC). This system constitutes a living interface between biomaterials and stem cells. The engineered biofilms remain stable and viable for up to 28 days while the expressed fibronectin fragment induces hMSC adhesion. We have optimised conditions to allow long-term mammalian cell culture and found that the biofilm is functionally equivalent to a fibronectin-coated surface in terms of osteoblastic differentiation using bone morphogenetic protein 2 (BMP-2) added to the medium. This living bacteria interface holds promise as a dynamic substrate for stem cell differentiation that can be further engineered to express other biochemical cues to control hMSC differentiation.
Beyond Rare-Variant Association Testing: Pinpointing Rare Causal Variants in Case-Control Sequencing Study
Authors: Lin Wan-Yu
Published: February 2016

Rare-variant association testing usually requires some method of aggregation. The next important step is to pinpoint individual rare causal variants among a large number of variants within a genetic region. Recently Ionita-Laza et al. propose a backward elimination (BE) procedure that can identify individual causal variants among the many variants in a gene. The BE procedure removes a variant if excluding this variant can lead to a smaller P-value for the BURDEN test (referred to as “BE-BURDEN”) or the SKAT test (referred to as “BE-SKAT”). We here use the adaptive combination of P-values (ADA) method to pinpoint causal variants. Unlike most gene-based association tests, the ADA statistic is built upon per-site P-values of individual variants. It is straightforward to select important variants given the optimal P-value truncation threshold found by ADA. We performed comprehensive simulations to compare ADA with BE-SKAT and BE-BURDEN. Ranking these three approaches according to positive predictive values (PPVs), the percentage of truly causal variants among the total selected variants, we found ADA > BE-SKAT > BE-BURDEN across all simulation scenarios. We therefore recommend using ADA to pinpoint plausible rare causal variants in a gene.
Discovery of 12-mer peptides that bind to wood lignin
Authors: Yamaguchi Asako , Isozaki Katsuhiro , Nakamura Masaharu , Takaya Hikaru , Watanabe Takashi
Published: February 2016

Lignin, an abundant terrestrial polymer, is the only large-volume renewable feedstock composed of an aromatic skeleton. Lignin has been used mostly as an energy source during paper production; however, recent interest in replacing fossil fuels with renewable resources has highlighted its potential value in providing aromatic chemicals. Highly selective degradation of lignin is pivotal for industrial production of paper, biofuels, chemicals and materials. However, few studies have examined natural and synthetic molecular components recognizing the heterogeneous aromatic polymer. Here, we report the first identification of lignin-binding peptides possessing characteristic sequences using a phage display technique. The consensus sequence HFPSP was found in several lignin-binding peptides and the outer amino acid sequence affected the binding affinity of the peptides. Substitution of phenylalanine7 with Ile in the lignin-binding peptide C416 (HFPSPIFQRHSH) decreased the affinity of the peptide for softwood lignin without changing its affinity for hardwood lignin, indicating that C416 recognised structural differences between the lignins. Circular dichroism spectroscopy demonstrated that this peptide adopted a highly flexible random coil structure, allowing key residues to be appropriately arranged in relation to the binding site in lignin. These results provide a useful platform for designing synthetic and biological catalysts selectively bind to lignin.
A potential therapeutic peptide-based neutralizer that potently inhibits Shiga toxin 2 in vitro and in vivo
Authors: Li Tao , Tu Wei , Liu Yuenan , Zhou Peng , Cai Kun , Li Zhan , Liu Xiong , Ning Nianzhi , Huang Jie , Wang Shenghan , Huang Jian , Wang Hui
Published: February 2016

Shiga toxin 2 (Stx2) is a major virulence factor in infections with Stx-producing Escherichia coli (STEC), which can cause serious clinical complications in humans, such as hemolytic uremic syndrome (HUS). Recently, we screened and identified two peptide-based Stx2 neutralizers, TF-1 and WA-8, which specifically and directly bind to Stx2. Computer simulations suggested that the majority of TF-1 or WA-8 binds tightly at the receptor-binding site 3 of Stx2. The two peptides also effectively inhibited the cytotoxic activity of Stx2 by blocking the binding of Stx2 to target cells. TF-1 exhibits remarkable therapeutic potency in both mice and rat toxicity models. In mice toxicity models, TF-1 provided full protection when mice were injected with 5 LD50 of Stx2. In rat toxicity models, TF-1 reduced fatal tissue damage and completely protected rats from the lethal challenges of Stx2. In these rats, TF-1 significantly decreased the concentration of Stx2 in blood and diminished tissue distribution levels of Stx2. Furthermore, TF-1 effectively protected rats from the pathological effects caused by Stx2, especially in the kidney, thymus, adrenal gland, and lung. Taken together, these results indicate that TF-1 is a promising therapeutic agent against the pathogenicity of Stx2.
Jasmonic acid is a crucial signal transducer in heat shock induced sesquiterpene formation in Aquilaria sinensis
Authors: Xu Yan-Hong , Liao Yong-Cui , Zhang Zheng , Liu Juan , Sun Pei-Wen , Gao Zhi-Hui , Sui Chun , Wei Jian-He
Published: February 2016

Agarwood, a highly valuable resinous and fragrant heartwood of Aquilaria plants, is widely used in traditional medicines, incense and perfume. Only when Aquilaria trees are wounded by external stimuli do they form agarwood sesquiterpene defensive compounds. Therefore, understanding the signaling pathway of wound-induced agarwood formation is important. Jasmonic acid (JA) is a well-characterized molecule that mediates a plant’s defense response and secondary metabolism. However, little is known about the function of endogenous JA in agarwood sesquiterpene biosynthesis. Here, we report that heat shock can up-regulate the expression of genes in JA signaling pathway, induce JA production and the accumulation of agarwood sesquiterpene in A. sinensis cell suspension cultures. A specific inhibitor of JA, nordihydroguaiaretic acid (NDGA), could block the JA signaling pathway and reduce the accumulation of sesquiterpene compounds. Additionally, compared to SA and H2O2, exogenously supplied methyl jasmonate has the strongest stimulation effect on the production of sesquiterpene compounds. These results clearly demonstrate the central induction role of JA in heat-shock-induced sesquiterpene production in A. sinensis.
Population structure and acquisition of the vanB resistance determinant in German clinical isolates of Enterococcus faecium ST192
Authors: Bender Jennifer K. , Kalmbach Alexander , Fleige Carola , Klare Ingo , Fuchs Stephan , Werner Guido
Published: February 2016

In the context of the global action plan to reduce the dissemination of antibiotic resistances it is of utmost importance to understand the population structure of resistant endemic bacterial lineages and to elucidate how bacteria acquire certain resistance determinants. Vancomycin resistant enterococci represent one such example of a prominent nosocomial pathogen on which nation-wide population analyses on prevalent lineages are scarce and data on how the bacteria acquire resistance, especially of the vanB genotype, are still under debate. With respect to Germany, an increased prevalence of VRE was noted in recent years. Here, invasive infections caused by sequence type ST192 VRE are often associated with the vanB-type resistance determinant. Hence, we analyzed 49 vanB-positive and vanB-negative E. faecium isolates by means of whole genome sequencing. Our studies revealed a distinct population structure and that spread of the Tn1549-vanB-type resistance involves exchange of large chromosomal fragments between vanB-positive and vanB-negative enterococci rather than independent acquisition events. In vitro filter-mating experiments support the hypothesis and suggest the presence of certain target sequences as a limiting factor for dissemination of the vanB element. Thus, the present study provides a better understanding of how enterococci emerge into successful multidrug-resistant nosocomial pathogens.
Prefrontal NAA and Glx Levels in Different Stages of Psychotic Disorders: a 3T 1H-MRS Study
Authors: Liemburg Edith , Sibeijn-Kuiper Anita , Bais Leonie , Pijnenborg Gerdina , Knegtering Henderikus , van der Velde Jorien , Opmeer Esther , de Vos Annerieke , Dlabac-De Lange Jozarni , Wunderink Lex , Aleman André
Published: February 2016

H-Magnetic Resonance Spectroscopy (1H-MRS) can offer insights in various neuropathologies by measuring metabolite levels in the brain. In the current study we investigated the levels of glutamate + glutamine (Glx, neurotransmitter and precursor) and N-Acetyl Aspartate + glutamic acid (NAA + NAAG; neuronal viability) in the prefrontal cortex of patients with a psychotic disorder and people at Ultra High Risk (UHR) for psychosis. A 1H-MRS spectrum was acquired in 31 patients with a recent onset psychotic disorder and 60 with a chronic state, 16 UHR patients and 36 healthy controls. Absolute metabolite levels were calculated using LCModel with a reference water peak. Groups were compared while taking into account age and partial volume effects. Moreover, we investigated associations with positive and negative symptoms, duration of illness and antipsychotic treatment in patients. The most notable finding is that chronicity of schizophrenia was related to decreased levels of Glx and NAA. On the other hand, although on an exploratory note, UHR showed increased levels of prefrontal Glx and NAA levels with increasing age. Our results may indicate an initial Glx and NAA increase and subsequent decrease during illness progression that may be related to the neurotoxic effects of glutamate.
A common mechanism involving the TORC1 pathway can lead to amphotericin B-persistence in biofilm and planktonic Saccharomyces cerevisiae populations
Authors: Bojsen Rasmus , Regenberg Birgitte , Gresham David , Folkesson Anders
Published: February 2016

Fungal infections are an increasing clinical problem. Decreased treatment effectiveness is associated with biofilm formation and drug recalcitrance is thought to be biofilm specific. However, no systematic investigations have tested whether resistance mechanisms are shared between biofilm and planktonic populations. We performed multiplexed barcode sequencing (Bar-seq) screening of a pooled collection of gene-deletion mutants cultivated as biofilm and planktonic cells. Screening for resistance to the ergosterol-targeting fungicide amphotericin B (AmB) revealed that the two growth modes had significant overlap in AmB-persistent mutants. Mutants defective in sterol metabolism, ribosome biosynthesis and the TORC1 and Ras pathways showed increased persistence when treated with AmB. The ras1, ras2 and tor1 mutants had a high-persister phenotype similar to wild-type biofilm and planktonic cells exposed to the TORC1 pathway inhibitor rapamycin. Inhibition of TORC1 with rapamycin also increased the proportion of persisters in Candida albicans and Candida glabrata. We propose that decreased TORC1-mediated induction of ribosome biosynthesis via Ras can lead to formation of AmB-persister cells regardless of whether the cells are in planktonic or biofilm growth mode. Identification of common pathways leading to growth mode-independent persister formation is important for developing novel strategies for treating fungal infections.