bluuebunny/crossref_metadata_2025 huggingface dataset:
Recommendations for choosing an analysis method that controls Type I error for unbalanced cluster sample designs with Gaussian outcomes
Authors: Johnson Jacqueline L. , Kreidler Sarah M. , Catellier Diane J. , Murray David M. , Muller Keith E. , Glueck Deborah H.
Published: June 2015

We used theoretical and simulation‐based approaches to study Type I error rates for one‐stage and two‐stage analytic methods for cluster‐randomized designs. The one‐stage approach uses the observed data as outcomes and accounts for within‐cluster correlation using a general linear mixed model. The two‐stage model uses the cluster specific means as the outcomes in a general linear univariate model. We demonstrate analytically that both one‐stage and two‐stage models achieve exact Type I error rates when cluster sizes are equal. With unbalanced data, an exact size α test does not exist, and Type I error inflation may occur. Via simulation, we compare the Type I error rates for four one‐stage and six two‐stage hypothesis testing approaches for unbalanced data. With unbalanced data, the two‐stage model, weighted by the inverse of the estimated theoretical variance of the cluster means, and with variance constrained to be positive, provided the best Type I error control for studies having at least six clusters per arm. The one‐stage model with Kenward–Roger degrees of freedom and unconstrained variance performed well for studies having at least 14 clusters per arm. The popular analytic method of using a one‐stage model with denominator degrees of freedom appropriate for balanced data performed poorly for small sample sizes and low intracluster correlation. Because small sample sizes and low intracluster correlation are common features of cluster‐randomized trials, the Kenward–Roger method is the preferred one‐stage approach. Copyright © 2015 John Wiley & Sons, Ltd.
Identifying correlations of findings for building process improvement packages using graph clustering
Authors: Choi Su‐Jin , Kim Dae‐Kyoo , Park Sooyong
Published: June 2015

Software process improvement (SPI) begins with process assessment based on a process reference model such as CMMI. Process improvement action items in SPI are determined according to the identified strengths and weaknesses of the current practice. Therefore, given that a list of assessment findings has been identified, it is important to analyze correlations of findings and identify relevant findings for building improvement items. However, correlation analysis requires expertise and considerable efforts, which makes it difficult for practitioners to perform it in process improvement projects. In this work, we present a CMMI‐based method for identifying correlations of findings and building improvement packages using graph clustering techniques. We evaluate the method using industrial data. Copyright © 2015 John Wiley & Sons, Ltd.
Starch to value added biochemicals
Authors: Roy Goswami Shrestha , Dumont Marie‐Josée , Raghavan Vijaya
Published: June 2015

An in‐depth review on the catalytic transformation of starch to a remarkable breadth of products is discussed. The physicochemical properties of starches from different varieties are reported to influence their functionality. However, the impact of such properties on the reaction parameters for the cost‐effective production of selective chemicals is largely unexplored. With the emergence of ionic liquids as the reaction media, water insoluble starch biopolymer can be easily dissolved and converted to reaction products simultaneously. Furthermore, microwave assisted chemical synthesis is known to enhance the reaction rates and optimize the resultant product selectivity. Physical and chemical modifications of starch also plays a vital role in the production of commodity chemicals. Recently, the potential routes to the production of biochemicals from biomass like glucaric acid, 5‐hydroxymethyl furfural, 2,5‐diformylfuran, 2,5‐furandicarboxylic acid, 2,5‐dimethylfuran, levulinic acid and sorbitol have been studied. Similar promising routes from inexpensive starches are analyzed in the review, as a function of the challenges associated to their chemical pathways and scalability.
Effects of chain structures of corn starches on starch‐based superabsorbent polymers
Authors: Zhang Ya‐Nan , Cui Jia‐Yang , Xu Shi‐Ai
Published: June 2015

Biodegradable superabsorbent polymers (SAPs) were synthesized in this study by graft copolymerization of monomers (acrylic acid or acrylamide) onto amylose and amylopectin, respectively, using potassium persulfate as an initiator and N,N′‐methylenebisacrylamide as a cross‐linker. The main purpose of this study is to investigate the effects of the chain structures of corn starches on the grafting ratio (GR) and physicochemical properties of starch‐based SAPs including starch‐graft‐polyacrylic acid and starch‐graft‐polyacrylamide SAPs. The structure of these SAPs was characterized by FTIR, 13C nuclear magnetic resonance (13C‐NMR), and thermogravimetric analysis (TGA), and the GR was evaluated by acid hydrolysis. We also investigated their swelling kinetics and reswelling capacity. The results show that the water absorption capacity and GR of amylose graft copolymers are superior to those of amylopectin graft copolymers; this may be due to the differences in structures and physicochemical properties between amylose and amylopectin.
We're Not in Kansas Anymore
Authors: Meese Ruth Lyn
Published: June 2015

Vowel teams such as vowel digraphs present a challenge to struggling readers. Some researchers assert that phonics generalizations such as the “two vowels go walking and the first one does the talking” rule do not hold often enough to be reliable for children. Others suggest that some vowel teams are highly regular and that children can apply their knowledge of vowel sounds to decode unknown words containing vowel teams. The TOTO Strategy provides a means for students to systematically use information about vowel sounds and the frequency of these sounds to “Try One and Try the Other” in order to decode words that make sense in context.
Tumour‐suppressive microRNA‐29s directly regulate LOXL2 expression and inhibit cancer cell migration and invasion in renal cell carcinoma
Authors: Nishikawa Rika , Chiyomaru Takeshi , Enokida Hideki , Inoguchi Satoru , Ishihara Tomoaki , Matsushita Ryosuke , Goto Yusuke , Fukumoto Ichiro , Nakagawa Masayuki , Seki Naohiko
Published: June 2015

Here, we found that members of the microRNA‐29 family (miR‐29a/b/c; “miR‐29s”) were significantly reduced in clear cell renal cell carcinoma (ccRCC) tissues, suggesting that they functioned as tumour suppressors. Restoration of all mature members of the miR‐29 family inhibited cancer cell proliferation, migration and invasion. LOXL2 was a direct target gene of miR‐29s, as shown by genome‐wide gene expression analysis and luciferase reporter assay. Overexpressed LOXL2 was confirmed in ccRCC clinical specimens, and silencing of LOXL2 inhibited cancer cell migration and invasion in ccRCC cell lines. Our data demonstrated that the miR‐29s‐LOXL2 axis contributed to cancer cell migration and invasion in ccRCC.
Diversity of COP9 signalosome structures and functional consequences
Authors: Dubiel Dawadschargal , Rockel Beate , Naumann Michael , Dubiel Wolfgang
Published: June 2015

The COP9 signalosome (CSN) is a regulator of the ubiquitin (Ub) proteasome system (UPS). It interacts with hundreds of cullin‐RING ubiquitin E3 ligases (CRLs) and regulates their activity by removing the Ub‐like protein Nedd8 from cullins. In mammalian cells 7 different cullins exist which form CRLs with adaptor proteins and with a large number of substrate recognition subunits such as F‐box and BTB proteins. This large variety of CRL‐complexes is deneddylated by the CSN. The capacity of the CSN to interact with numerous types of CRL complexes can be explained by its structural diversity, which allows different CSN variants to interact with different binding partners and substrates and enables different subunit expression profiles. Diversity of CSN complexes presumably occurs by: (1) flexibility of CSN holo complex structure; (2) formation of CSN mini complexes and free CSN subunits and (3) generation of CSN variantsvia integration of CSN subunit isoforms. In this review we will discuss the structural diversity of the CSN complex and possible functional consequences.
LINC'ing form and function at the nuclear envelope
Authors: Meinke Peter , Schirmer Eric C.
Published: June 2015

The nuclear envelope is an amazing piece of engineering. On one hand it is built like a mediaeval fortress with filament systems reinforcing its membrane walls and its double membrane structure forming a lumen like a castle moat. On the other hand its structure can adapt while maintaining its integrity like a reed bending in a river. Like a fortress it has guarded drawbridges in the nuclear pore complexes, but also has other mechanical means of communication. All this is enabled largely because of the LINC complex, a multi‐protein structure that connects the intermediate filament nucleoskeleton across the lumen of the double membrane nuclear envelope to multiple cytoplasmic filament systems that themselves could act simultaneously both like mediaeval buttresses and like lines on a suspension bridge. Although many details of the greater LINC structure remain to be discerned, a number of recent findings are giving clues as to how its structural organization can yield such striking dynamic yet stable properties. Combining double‐ and triple‐helical coiled‐coils, intrinsic disorder and order, tissue‐specific components, and intermediate filaments enables these unique properties.
Challenges affecting access to cesarean delivery and strategies to overcome them in low‐income countries
Authors: Irani Mohamad , Deering Shad
Published: June 2015

Background

Most maternal deaths occur in low‐income countries where access to appropriate medical care is restricted.

Objectives

To evaluate rates of cesarean deliveries and identify barriers to this mode of delivery in low‐income countries.

Search strategy

A review of Medline and PubMed was performed to identify reports published in English or French using the keywords “cesarean section,” “maternal mortality,” and “developing countries.”

Selection criteria

Studies investigating the obstacles to cesarean delivery and plans to overcome them in low‐income countries were included.

Data collection and analysis

Data from included studies were extracted and analyzed.

Main results

Studies from 16 countries in Sub‐Saharan Africa were included. The average rate of cesarean delivery was 3.6% (range 1.5%–7.1%). The rate was negatively correlated with the maternal mortality ratio (r = −0.63; P = 0.005), neonatal mortality rate (r = −0.81; P < 0.001), and infant mortality rate (r = −0.80; P < 0.001). Major barriers to achieving higher rates of cesarean deliveries include poverty, limited access to healthcare services, and a shortage of skilled providers.

Conclusions

Maternal and infant mortality rates could be lowered by increasing access to cesarean delivery. Additional education of patients and providers, establishment of more heath facilities, and governmental support of obstetric care could help to reach this goal.
A phase 2 randomized, controlled trial of the α7 agonist ABT‐126 in mild‐to‐moderate Alzheimer's dementia
Authors: Gault Laura M. , Ritchie Craig W. , Robieson Weining Z. , Pritchett Yili , Othman Ahmed A. , Lenz Robert A.
Published: June 2015

Introduction

The safety and efficacy of the novel α7 nicotinic acetylcholine receptor agonist ABT‐126 were investigated in subjects with mild‐to‐moderate Alzheimer's dementia (AD).

Methods

Subjects not currently receiving acetylcholinesterase inhibitors were randomized to ABT‐126 (5 or 25 mg once daily), donepezil 10 mg once daily, or placebo for 12 weeks. The primary efficacy end point was the change from baseline to final evaluation in the 11‐item Alzheimer's Disease Assessment Scale‐cognitive subscale (ADAS‐Cog) total score.

Results

A total of 274 subjects were randomized. Although the study did not meet its primary end point, trends toward improvement were seen with ABT‐126 25 mg (least squares mean [standard error] difference from placebo −1.19 [0.90]; one‐sided P = .095) and donepezil (−1.43 [0.90]; one‐sided P = .057) on the 11‐item ADAS‐Cog total score change from baseline to the final evaluation. ABT‐126 5 mg was numerically similar to placebo. An exposure‐response analysis indicated a statistically significant relationship between ABT‐126 exposure and the change from baseline in ADAS‐Cog, with no evidence of a plateau. No clinically meaningful differences in safety were observed among treatment groups.

Discussion

Although the ABT‐126 25 mg dose did not demonstrate statistically significant improvement, results of the exposure‐response analysis suggest that higher doses may produce better efficacy, and the safety profile of ABT‐126 in this study supports additional studies with higher doses in subjects with mild‐to‐moderate AD.

Clinical trial register number

NCT00948909.
Consciousness Without Attention
Authors: JENNINGS CAROLYN DICEY
Published: June 2015

This paper explores whether consciousness can exist without attention. This is a hot topic in philosophy of mind and cognitive science due to the popularity of theories that hold attention to be necessary for consciousness. The discovery of a form of consciousness that exists without the influence of attention would require a change in the way that many global workspace theorists, for example, understand the role and function of consciousness. Against this understanding, at least three forms of consciousness have been argued to exist without attention: perceptual gist, imagistic consciousness, and phenomenal consciousness. After first arguing that the evidence is inconclusive on the question of whether these forms of consciousness exist without attention, I here present a fourth form of consciousness that is likely to be more successful: conscious entrainment. I argue that conscious entrainment is a form of consciousness associated with skilled behavior in which attention is sometimes absent.
What Is Democracy (and What Is Its Raison D’Etre)?
Authors: GOLDMAN ALVIN I.
Published: June 2015

This article aims to say what democracy is or what the predicate ‘democratic’ means, as opposed to saying what is good, right, or desirable about it. The basic idea—by no means a novel one—is that a democratic system is one that features substantial equality of political power. More distinctively it is argued that ‘democratic’ is a relative gradable adjective, the use of which permits different, contextually determined thresholds of democraticness. Thus, a system can be correctly called ‘democratic’ even if it does not feature perfect equality of power. The article's central undertaking is to give greater precision to the operative notion(s) of power. No complete or fully unified measure of power is offered, but several conceptual tools are introduced that help give suitable content to power measurement. These tools include distinctions between conditional versus unconditional power and direct versus indirect power. Using such tools, a variety of prima facie problems for the power equality approach are addressed and defused. Finally, the theory is compared to epistemic and deliberative approaches to democracy; and reasons are offered for the attractiveness of democracy that flows from the power equality theme.
Viscous–poroelastic interaction as mechanism to create adhesion in frogs’ toe pads
Authors: Tulchinsky A. , Gat A. D.
Published: June 2015

The toe pads of frogs consist of soft hexagonal structures and a viscous liquid contained between and within the hexagonal structures. It has been hypothesized that this configuration creates adhesion by allowing for long-range capillary forces, or, alternatively, by allowing for exit of the liquid and thus improving contact of the toe pad. In this work, we suggest interaction between viscosity and elasticity as a mechanism to create temporary adhesion, even in the absence of capillary effects or van der Waals forces. We initially illustrate this concept experimentally by a simplified configuration consisting of two surfaces connected by a liquid bridge and elastic springs. We then utilize poroelastic mixture theory and model frogs’ toe pads as an elastic porous medium, immersed within a viscous liquid and pressed against a rigid rough surface. The flow between the surface and the toe pad is modelled by the lubrication approximation. Inertia is neglected and analysis of the elastic–viscous dynamics yields a governing partial differential equation describing the flow and stress within the porous medium. Several solutions of the governing equation are presented and show a temporary adhesion due to stress created at the contact surface between the solids. This work thus may explain how some frogs (such as the torrent frog) maintain adhesion underwater and the reason for the periodic repositioning of frogs’ toe pads during adhesion to surfaces.
Neither Physicians Nor Surgeons: Whither Neuropathological Skill in Post-war England?
Authors: Schoefert Anna Kathryn
Published: June 2015

Neuropathologists constituted a small field in post-war England, perched between neurology, psychiatry, neurosurgery and pathology, but recognised as a discrete field of expertise. Despite this recognition, the success of the neighbouring fields of neurosurgery, psychosurgery and neurobiology, and the consultant status granted to pathologists in the National Health Service, neuropathologists struggled to stabilise their field. A discourse of skills, acquired and acquirable, became central to their attempts to situate the field in relation to surgeons’ handicraft, physicians’ diagnostic acumen and the technologies of the biological sciences.
Do the abundance, diversity, and community structure of sediment meiofauna differ among seagrass species?
Authors: Liao Jian-Xiang , Yeh Hsin-Ming , Mok Hin-Kiu
Published: June 2015

The structural complexity of macrophytes that provide various microhabitats is related to local infaunal abundance and diversity. Seagrass is considered an ecosystem engineer that alters the benthic environment and enables certain distinct meiofauna to thrive in sediments. The effects of seagrass species in a mixed-species seagrass bed at Haikou, Taiwan were examined. Analysing quantitative samples obtained from patches ofThalassia hemprichii, Halodule uninervis, Halophila ovalisand adjacent unvegetated sediments inspected the community structures of meiofauna and marine nematodes. The abundance and diversity of crustaceans and nematodes were substantially higher in habitats in which seagrass grew than in those comprising unvegetated sediments. Both the compositions of higher meiofaunal taxa and nematode species were distinct between seagrass habitats and unvegetated areas. Several nematode species existed exclusively in patches of individual seagrass species, whereas no nematode specifically occurred in unvegetated areas. Regarding the trophic types of nematodes, non-selective deposit feeders were prevalent in the present study, whereas selective deposit feeders and epistrate feeders were relatively dominant in seagrass habitats. Sediments underneath various patches of seagrass species harbour dissimilar nematode communities, even with similar sediment parameters and at a small-scale distance.
Fear of crime and older people in low- and middle-income countries
Authors: LLOYD-SHERLOCK PETER , AGRAWAL SUTAPA , MINICUCI NADIA
Published: June 2015

This paper analyses data from the World Health Organization's Study on Global AGEing and Adult Health (SAGE) on the prevalence of reported fear of crime at home and on the street among older people in China, Ghana, India, Mexico, Russia and South Africa. SAGE provides nationally representative data for 35,125 people aged 50 and over. These reveal large national variations in reported crime fear: for example, 65 per cent of older South Africans felt unsafe on the street, compared to only 9 per cent of older Ghanaians. The paper examines factors potentially associated with crime fear, including age, socio-economic status and frailty, and relates these to different theoretical models of crime fear. Female sex and frailty are associated with higher rates of crime fear across the study countries. Other associations are less consistent, e.g. urban residence is associated with higher levels of fear in some countries and lower levels in others. The paper considers the potential effects of crime fear on mobility beyond the home, health status and quality of life. A strong association is found for mobility, but effects on health and quality of life are harder to interpret as the direction of causality can be two-way. Overall, the paper demonstrates the potential impact of crime fear on older people's wellbeing and highlights a need for further, more contextualised research.
The 2011 Debt-Ceiling Controversy and the 2012 US House Elections
Authors: Monogan James E.
Published: June 2015

This article considers how a key legislative vote—that is, the August 2011 vote to raise the federal debt ceiling—influenced the 2012 elections for the US House of Representatives. Two outcomes are analyzed: (1) the incumbents’ ability to retain their seats through the 2012 general election, and (2) their share of the two-party vote for members who faced a general-election competitor. In developing this study, the research design was registered and released publicly before the votes were counted in 2012. Therefore, this article also illustrates how study preregistration can work in practice for political science. The findings show that seat retention did not vary with the treatment; however, incumbents who voted against raising the debt ceiling earned an additional 2.4 percentage points of the two-party vote.
Finding the Invisible Women: Gender Stereotypes versus Student Interest in Foreign Policy and Security Subfields
Authors: Buhr Renee L. , Sideras Nicholas
Published: June 2015

Foreign policy and security studies typically are considered male-dominated domains in the discipline of international relations (IR), yet many women work in these policy domains, particularly in the United States. The “invisible women” working in foreign policy often come from fields such as IR, in which gender stereotypes may influence their understanding of the careers available to them. This research project seeks to understand student assumptions about gender roles in IR and the effects of those assumptions. Survey data collected from students in IR courses in 2011 and 2012 reveal that stereotyping of IR subfields is common but that individual students’ academic and career interests often diverge from those stereotypes. This finding is relevant not simply because it may explain the presence of women in foreign-policy careers but also because it provides useful pedagogical information for instructors in the IR field.
Want to Study the Nature of Power? Start by Moving the Chairs!
Authors: Mott Meg
Published: June 2015

At first glance, the political-theory classroom can seem like a “philosophy class in disguise.” How can we make our text-based classes more “political”? This article considers how three teaching formats—debate, fishbowl, and forum theater—enact different types of power in the classroom and how those enactments necessitate political judgments. In addition to creating the need for political analysis, each of these formats embodies a particular rhetorical strategy often used by political theorists. By physicalizing the argumentative, introspective, and descriptive devices that writers of political theory use, students become better readers of these often old and usually dense texts.
Determinants of vitamin D supplement use in Canadians
Authors: McCormack Daniel , Mai Xiaomei , Chen Yue
Published: June 2015

Objective

To determine the prevalence of vitamin D supplement use in Canadian adults and associations with demographic and socio-economic variables.

Design

Data from the Healthy Aging module of the Canadian Community Health Survey were used to investigate the prevalence of vitamin D supplement use in Canadians aged 45 years and over. The prevalence of supplement use stratified by various behavioural and demographic characteristics was calculated and adjusted models were used to find associations with those factors.

Setting

The ten provinces of Canada.

Subjects

Canadians aged 45 years and over who participated in the Healthy Aging module of the Canadian Community Health Survey from 2008–2009.

Results

The highest observed prevalence for women was 48·0 % in the 65–69 years age group and the highest prevalence for men was 25·3 % in the 70–74 years age group. Women had higher odds of vitamin D supplement use than men in all age groups. Not using supplements was more common in smokers, those who did not engage in leisure-time physical activities and who were either overweight or obese. Vitamin D supplement use increased with household income and level of education, and decreased with self-perceived health. Supplement use was higher in those with chronic conditions.

Conclusions

The inverse association with self-perceived health could be partly explained by age, chronic conditions and increased use of health-care services. Associations with higher income and education suggest a strong socio-economic influence and that individuals may not have the expendable income to purchase vitamin D supplements or knowledge of their health benefits.
Development of an existential support training program for healthcare professionals
Authors: Henoch Ingela , Strang Susann , Browall Maria , Danielson Ella , Melin-Johansson Christina
Published: June 2015

Objective:

Our aim was to describe the developmental process of a training program for nurses to communicate existential issues with severely ill patients.

Method:

The Medical Research Council (MRC) framework for the development and evaluation of complex interventions was used to develop a training program for nurses to communicate about existential issues with their patients. The steps in the framework were employed to describe the development of the training intervention, and the development, feasibility and piloting, evaluation, and implementation phases. The development and feasibility phases are described in the Methods section. The evaluation and implementation phases are described in the Results section.

Results:

In the evaluation phase, the effectiveness of the intervention was shown as nurses' confidence in communication increased after training. The understanding of the change process was considered to be that the nurses could describe their way of communicating in terms of prerequisites, process, and content. Some efforts have been made to implement the training intervention, but these require further elaboration.

Significance of results:

Existential and spiritual issues are very important to severely ill patients, and healthcare professionals need to be attentive to such questions. It is important that professionals be properly prepared when patients need this communication. An evidence-based training intervention could provide such preparation. Healthcare staff were able to identify situations where existential issues were apparent, and they reported that their confidence in communication about existential issues increased after attending a short-term training program that included reflection. In order to design a program that should be permanently implemented, more knowledge is needed of patients' perceptions of the quality of the healthcare staff's existential support.
Efficiency of Arithmetic Procedures Modulates the Problem-Size Effect in Subtraction
Authors: Núñez-Peña M. Isabel , Colomé Angels , Tubau Elisabet
Published: June 2015

The aim of this study was to examine whether differences in strategy selection and/or strategy efficiency can explain the modulation of the problem-size effect by arithmetic skill. More specifically, we wondered whether arithmetic skill increases the use of retrieval strategy in large problems, and/or enhances the efficiency of either retrieval or procedural strategies. The performance of highly-skilled (HS) and less highly-skilled (LS) individuals on a subtraction verification task was analyzed according to problem size and to the strategy reported on a trial-by-trial basis after each problem. The problem size effect was larger for LS individuals than for their HS peers, both in response time and in hit rate. Nevertheless, groups did not differ regarding the strategy reported for each subtraction size. As expected, problems in which retrieval strategy was reported were solved more quickly and more accurately than problems solved by procedural strategies. Responses using retrieval strategy were equally fast in the two groups, but HS individuals performed better than LS when using procedural strategies. The results therefore suggest that the differences in behavioral measures between groups might specifically be due to differences in the efficiency of procedural strategies.
Professional Care as an Option Prior to Self-Harm
Authors: Idenfors Hans , Kullgren Gunnar , Salander Renberg Ellinor
Published: June 2015

Abstract. Background: Deliberate self-harm (DSH) is a growing problem among young people and is a major risk factor for suicide. Young adults experiencing mental distress and suicidal ideation are reluctant to seek help, requiring new strategies to reach this group. Aims: The present study explored young people's views of professional care before first contact for DSH, and factors that influenced the establishing of contact. Method: Interviews with 10 young individuals, shortly after they had harmed themselves, were analyzed using qualitative content analysis. Results: The participants emphasized the importance of receiving more knowledge on where to turn, having different help-seeking options, and receiving immediate help. Family and friends were vital for support and making health care contact. The quality of the professional contact was stressed. Several reasons for not communicating distress were mentioned. Two themes were identified: "A need for a more flexible, available and varied health care" and "A struggle to be independent and yet being in need of reliable support." Conclusion: These findings suggest that easy and direct access to professional help is a decisive factor for young people experiencing psychological problems and that health services must find new ways of communicating information on seeking mental health help.
Emergent vortices in populations of colloidal rollers
Authors: Bricard Antoine , Caussin Jean-Baptiste , Das Debasish , Savoie Charles , Chikkadi Vijayakumar , Shitara Kyohei , Chepizhko Oleksandr , Peruani Fernando , Saintillan David , Bartolo Denis
Published: June 2015

Coherent vortical motion has been reported in a wide variety of populations including living organisms (bacteria, fishes, human crowds) and synthetic active matter (shaken grains, mixtures of biopolymers), yet a unified description of the formation and structure of this pattern remains lacking. Here we report the self-organization of motile colloids into a macroscopic steadily rotating vortex. Combining physical experiments and numerical simulations, we elucidate this collective behaviour. We demonstrate that the emergent-vortex structure lives on the verge of a phase separation, and single out the very constituents responsible for this state of polar active matter. Building on this observation, we establish a continuum theory and lay out a strong foundation for the description of vortical collective motion in a broad class of motile populations constrained by geometrical boundaries.
Complex Learning in Bio-plausible Memristive Networks
Authors: Deng Lei , Li Guoqi , Deng Ning , Wang Dong , Zhang Ziyang , He Wei , Li Huanglong , Pei Jing , Shi Luping
Published: June 2015

The emerging memristor-based neuromorphic engineering promises an efficient computing paradigm. However, the lack of both internal dynamics in the previous feedforward memristive networks and efficient learning algorithms in recurrent networks, fundamentally limits the learning ability of existing systems. In this work, we propose a framework to support complex learning functions by introducing dedicated learning algorithms to a bio-plausible recurrent memristive network with internal dynamics. We fabricate iron oxide memristor-based synapses, with well controllable plasticity and a wide dynamic range of excitatory/inhibitory connection weights, to build the network. To adaptively modify the synaptic weights, the comprehensive recursive least-squares (RLS) learning algorithm is introduced. Based on the proposed framework, the learning of various timing patterns and a complex spatiotemporal pattern of human motor is demonstrated. This work paves a new way to explore the brain-inspired complex learning in neuromorphic systems.
Hybrid System for Ex Vivo Hemorheological and Hemodynamic Analysis: A Feasibility Study
Authors: Yeom Eunseop , Jun Kang Yang , Joon Lee Sang
Published: June 2015

Precise measurement of biophysical properties is important to understand the relation between these properties and the outbreak of cardiovascular diseases (CVDs). However, a systematic measurement for these biophysical parameters under in vivo conditions is nearly impossible because of complex vessel shape and limited practicality. In vitro measurements can provide more biophysical information, but in vitro exposure changes hemorheological properties. In this study, a hybrid system composed of an ultrasound system and microfluidic device is proposed for monitoring hemorheological and hemodynamic properties under more reasonable experimental conditions. Biophysical properties including RBC aggregation, viscosity, velocity and pressure of blood flows are simultaneously measured under various conditions to demonstrate the feasibility and performance of this measurement system. The proposed technique is applied to a rat extracorporeal loop which connects the aorta and jugular vein directly. As a result, the proposed system is found to measure biophysical parameters reasonably without blood collection from the rat and provided more detailed information. This hybrid system, combining ultrasound imaging and microfluidic techniques to ex vivo animal models, would be useful for monitoring the variations of biophysical properties induced by chemical agents. It can be used to understand the relation between biophysical parameters and CVDs.
Swedish mutant APP-based BACE1 binding site peptide reduces APP β-cleavage and cerebral Aβ levels in Alzheimer’s mice
Authors: Li Song , Hou Huayan , Mori Takashi , Sawmiller Darrell , Smith Adam , Tian Jun , Wang Yanjiang , Giunta Brian , Sanberg Paul R. , Zhang Sheqing , Tan Jun
Published: June 2015

BACE1 initiates amyloid-β (Aβ) generation and the resultant cerebral amyloidosis, as a characteristic of Alzheimer’s disease (AD). Thus, inhibition of BACE1 has been the focus of a large body of research. The most recent clinical trials highlight the difficulty involved in this type of anti-AD therapy as evidenced by side effects likely due to the ubiquitous nature of BACE1, which cleaves multiple substrates. The human Swedish mutant form of amyloid protein precursor (APPswe) has been shown to possess a higher affinity for BACE1 compared to wild-type APP (APPwt). We pursued a new approach wherein harnessing this greater affinity to modulate BACE1 APP processing activity. We found that one peptide derived from APPswe, containing the β-cleavage site, strongly inhibits BACE1 activity and thereby reduces Aβ production. This peptide, termed APPswe BACE1 binding site peptide (APPsweBBP), was further conjugated to the fusion domain of the HIV-1 Tat protein (TAT) at the C-terminus to facilitate its biomembrane-penetrating activity. APPwt and APPswe over-expressing CHO cells treated with this TAT-conjugated peptide resulted in a marked reduction of Aβ and a significant increase of soluble APPα. Intraperitoneal administration of this peptide to 5XFAD mice markedly reduced β-amyloid deposits as well as improved hippocampal-dependent learning and memory.
Screening Mutations of MYBPC3 in 114 Unrelated Patients with Hypertrophic Cardiomyopathy by Targeted Capture and Next-generation Sequencing
Authors: Liu Xuxia , Jiang Tengyong , Piao Chunmei , Li Xiaoyan , Guo Jun , Zheng Shuai , Zhang Xiaoping , Cai Tao , Du Jie
Published: June 2015

Hypertrophic cardiomyopathy (HCM) is a major cause of sudden cardiac death. Mutations in the MYBPC3 gene represent the cause of HCM in ~35% of patients with HCM. However, genetic testing in clinic setting has been limited due to the cost and relatively time-consuming by Sanger sequencing. Here, we developed a HCM Molecular Diagnostic Kit enabling ultra-low-cost targeted gene resequencing in a large cohort and investigated the mutation spectrum of MYBPC3. In a cohort of 114 patients with HCM, a total of 20 different mutations (8 novel and 12 known mutations) of MYBPC3 were identified from 25 patients (21.9%). We demonstrated that the power of targeted resequencing in a cohort of HCM patients and found that MYBPC3 is a common HCM-causing gene in Chinese patients. Phenotype-genotype analyses showed that the patients with double mutations (n = 2) or premature termination codon mutations (n = 12) showed more severe manifestations, compared with patients with missense mutations (n = 11). Particularly, we identified a recurrent truncation mutation (p.Y842X) in four unrelated cases (4/25, 16%), who showed severe phenotypes and suggest that the p.Y842X is a frequent mutation in Chinese HCM patients with severe phenotypes.
Effect of papain-based gel on type I collagen - spectroscopy applied for microstructural analysis
Authors: Júnior Zenildo Santos Silva , Botta Sergio Brossi , Ana Patricia Aparecida , França Cristiane Miranda , Fernandes Kristianne Porta Santos , Mesquita-Ferrari Raquel Agnelli , Deana Alessandro , Bussadori Sandra Kalil
Published: June 2015

Considering the improvement of biomaterials that facilitate atraumatic restorative techniques in dentistry, a papain-based gel can be used in the chemomechanical removal of decayed dental tissue. However, there is no information regarding the influence of this gel on the structure of sound collagen. The aim of the present study was to investigate the adsorption of a papain-based gel (PapacarieTM) to collagen and determine collagen integrity after treatment. A pilot study was first performed with 10 samples of type I collagen membrane obtained from bovine Achilles deep tendon to compare the influence of hydration (Milli-Q water) on infrared bands of collagen. In a further experiment, 10 samples of type I collagen membrane were used to evaluate the effects of PapacarieTM on the collagen microstructure. All analyses were performed using the attenuated total reflectance technique of Fourier transform infrared (ATR-FTIR). The results demonstrated that the application of PapacarieTM does not lead to the degradation of collagen and this product can be safely used in minimally invasive dentistry. As the integrity of sound collagen is preserved after the application of the papain-based gel, this product is indicated for the selective removal of infected dentin, leaving the affected dentin intact and capable of re-mineralization.
Altered baseline brain activity differentiates regional mechanisms subserving biological and psychological alterations in obese men
Authors: Zhang Bin , Tian Derun , Yu Chunshui , Li Meng , Zang Yufeng , Liu Yijun , Walter Martin
Published: June 2015

Obesity as a chronic disease is a major factor for insulin resistance and Type 2 diabetes, which has become a global health problem. In the present study, we used resting state functional MRI to investigate the amplitude of low frequency fluctuations of spontaneous signal during both hunger and satiety states in 20 lean and 20 obese males. We found that, before food intake, obese men had significantly greater baseline activity in the precuneus and lesser activity in dorsal anterior cingulate cortex (dACC) relative to lean subjects. Furthermore, after food intake, obese males had significantly lesser activity in dACC than lean males. We further found a significant positive correlation between precuneus activation and hunger ratings before food intake, while dACC activity was negatively correlated with plasma insulin levels before and after food intake. These results indicated that both precuneus and dACC may play an important role in eating behavior. While precuneus rather seemed to mediate subjective satiety, dACC levels rather reflected indirect measures of glucose utilization.
Tribological performance of Graphene/Carbon nanotube hybrid reinforced Al2O3 composites
Authors: Yazdani Bahareh , Xu Fang , Ahmad Iftikhar , Hou Xianghui , Xia Yongde , Zhu Yanqiu
Published: June 2015

Tribological performance of the hot-pressed pure Al2O3 and its composites containing various hybrid contents of graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) were investigated under different loading conditions using the ball-on-disc method. Benchmarked against the pure Al2O3, the composite reinforced with a 0.5 wt% GNP exhibited a 23% reduction in the friction coefficient along with a promising 70% wear rate reduction and a hybrid reinforcement consisting of 0.3 wt.% GNPs + 1 wt.% CNTs resulted in even better performance, with a 86% reduction in the wear rate. The extent of damage to the reinforcement phases caused during wear was studied using Raman spectroscopy. The wear mechanisms for the composites were analysed based on the mechanical properties, brittleness index and microstructural characterizations. The excellent coordination between GNPs and CNTs contributed to the excellent wear resistance property in the hybrid GNT-reinforced composites. GNPs played the important role in the formation of a tribofilm on the worn surface by exfoliation; whereas CNTs contributed to the improvement in fracture toughness and prevented the grains from being pulled out during the tribological test.
Evidence for horizontal transfer of mitochondrial DNA to the plastid genome in a bamboo genus
Authors: Ma Peng-Fei , Zhang Yu-Xiao , Guo Zhen-Hua , Li De-Zhu
Published: June 2015

In flowering plants, three genomes (nuclear, mitochondrial and plastid) coexist and intracellular horizontal transfer of DNA is prevalent, especially from the plastid to the mitochondrion genome. However, the plastid genomes are generally conserved in evolution and have long been considered immune to foreign DNA. Recently, the opposite direction of DNA transfer from the mitochondrial to the plastid genome has been reported in two eudicot lineages. Here we sequenced 6 plastid genomes of bamboos, three of which are neotropical woody species and three are herbaceous ones. Several unusual features were found, including the duplication of trnT-GGU and loss of one copy of rps19 due to contraction of inverted repeats (IRs). The most intriguing was the ~2.7 kb insertion in the plastid IR regions in the three herbaceous bamboos. Furthermore, the insertion was documented to be horizontally transferred from the mitochondrial to the plastid genome. Our study provided evidence of the mitochondrial-to-plastid DNA transfer in the monocots, demonstrating again that this rare event does occur in other angiosperm lineages. However, the mechanism underlying the transfer remains obscure and more studies in other plants may elucidate it in the future.
Lifetimes and stabilities of familiar explosive molecular adduct complexes during ion mobility measurements
Authors: McKenzie-Coe Alan , DeBord John Daniel , Ridgeway Mark , Park Melvin , Eiceman Gary , Fernandez-Lima Francisco
Published: June 2015

The capability of TIMS-MS to measure explosives from complex mixturesviamolecular adduct complexes and to measure relative stabilities and lifetimes is shown.
Self-assembly of various silver nanocrystals on PmPD/PAN nanofibers as a high-performance 3D SERS substrate
Authors: Jia Peng , Cao Bing , Wang Jianqiang , Qu Jin , Liu Yuxuan , Pan Kai
Published: June 2015

The AgNCs (AgNPs, AgNTs and AgNDs) decorated-PmPD/PAN nanofiber mats were obtained as highly sensitive 3D SERS substrates.
Hybrid, multiplexed, functional DNA nanotechnology for bioanalysis
Authors: Wang L. , Arrabito G.
Published: June 2015

DNA nanotechnology allows for the realization of novel multiplexed assays in bioanalytical sciences.
A facile method for fabrication of buckled PDMS silver nanorod arrays as active 3D SERS cages for bacterial sensing
Authors: Kumar Samir , Lodhi Devesh K. , Goel Pratibha , Neeti Neeti , Mishra Prashant , Singh J. P.
Published: June 2015

We have successfully demonstrated a simple and facile method to increase the SERS signal of bacteria due to the formation of high density hotspots among the AgNRs and the increase in the area for better interaction of bacteria with the metal surface.
Synthesis of 3-chloro-6-((4-(di-tert-butyl[18F]fluorosilyl)-benzyl)oxy)-1,2,4,5-tetrazine ([18F]SiFA-OTz) for rapid tetrazine-based18F-radiolabeling
Authors: Zhu Jun , Li Stephen , Wängler Carmen , Wängler Björn , Bruce Lennox R. , Schirrmacher Ralf
Published: June 2015

[18F]-SiFA-OTz was synthesized within 25 min with a radiochemical yield of 78 ± 5% and can quantitatively react with strained dienophiles.
A novel deep photodynamic therapy modality combined with CT imaging established via X-ray stimulated silica-modified lanthanide scintillating nanoparticles
Authors: Elmenoufy Ahmed H. , Tang Yong'an , Hu Jun , Xu Huibi , Yang Xiangliang
Published: June 2015

A novel theranostic nanosystem was established via X-ray excited LaF3:Tb scintillating nanoparticles capable of deep-seated tumour photodynamic therapy.
A target-induced three-way G-quadruplex junction for 17β-estradiol monitoring with a naked-eye readout
Authors: Chen Junhua , Wen Junlin , Yang Guiqin , Zhou Shungui
Published: June 2015

A three-way G-quadruplex junction for 17β-estradiol monitoring has been constructed based on split G-quadruplex DNAzyme and toehold-mediated strand displacement.
Hexacyclic lactam building blocks for highly efficient polymer solar cells
Authors: Cao Jiamin , Zuo Chuantian , Du Bin , Qiu Xiaohui , Ding Liming
Published: June 2015

Four D–A copolymers based on new fused-ring acceptor units were developed, and an 8.18% PCE record was demonstrated for D–A copolymers using selenophene as the donor unit.
Orbit and spin resolved magnetic properties of size selected [ConRh]+ and [ConAu]+ nanoalloy clusters
Authors: Dieleman Dennis , Tombers Matthias , Peters Lars , Meyer Jennifer , Peredkov Sergey , Jalink Jeroen , Neeb Matthias , Eberhardt Wolfgang , Rasing Theo , Niedner-Schatteburg Gereon , Kirilyuk Andrei
Published: June 2015

XMCD measurements on doped Co clusters in the gas phase reveal their fluctuating spin and orbital magnetic moments.
High-throughput approach for the identification of anilinium-based ionic liquids that are suitable for electropolymerisation
Authors: Abdelhamid Muhammad E. , Murdoch Timothy , Greaves Tamar L. , O'Mullane Anthony P. , Snook Graeme A.
Published: June 2015

We report the synthesis of new protic ionic liquids (PILs) based on aniline derivatives and the use of high-throughput (HT) techniques to screen possible candidates.
Factors influencing the photocatalytic activity of rutile TiO2 nanorods with different aspect ratios for dye degradation and Cr(vi) photoreduction
Authors: Yang Zewei , Wang Bing , Zhang Jin , Cui Hao , Pan Yang , An Hao , Zhai Jianping
Published: June 2015

The aspect ratio of rutile TiO2 nanorods is a key factor influencing photocatalytic MB degradation. The conduction band potential plays significant roles in the photocatalytic reduction of Cr(vi).
The electronic structure of quasi-free-standing germanene on monolayer MX (M = Ga, In; X = S, Se, Te)
Authors: Ni Zeyuan , Minamitani Emi , Ando Yasunobu , Watanabe Satoshi
Published: June 2015

For the first time by using the ab initio density functional theory, the stability and electronic structures of germanene on monolayer GaS, GaSe, GaTe and InSe have been investigated.