bluuebunny/crossref_metadata_2025 huggingface dataset:
Variable selection using P‐splines
Authors: Gijbels Irène , Verhasselt Anneleen , Vrinssen Inge
Published: September 2014

Selecting among a large set of variables those that influence most a response variable is an important problem in statistics. When the assumed regression model involves a nonparametric component, penalized regression techniques, and in particular P‐splines, are among the commonly used methods. The aim of this paper is to provide a brief review of variable selection methods using P‐splines. Starting from multiple linear regression models, with least‐squares regression, and Ridge regression, we review standard methods that perform variable selection, such as LASSO, nonnegative garrote, the SCAD method, etc. We briefly discuss a general framework of penalization and regularization methods. Going toward more flexible regression models, with some nonparametric component(s), we discuss P‐splines estimation. For some examples of flexible regression models, we then review a few variable selection methods using P‐splines. A brief discussion on grouped regularization techniques and on a robust variable selection method is given. Furthermore, we mention key ingredients in Bayesian approaches, and end the paper by drawing the attention to several other issues in variable selection with P‐splines. Throughout the paper we provide some illustrations.WIREs Comput Stat2015, 7:1–20. doi: 10.1002/wics.1327

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Nonparametric Methods

Statistical Models > Model Selection
Using DNA to evaluate field identification of cougar sex by agency staff and hunters using trained dogs
Authors: Beausoleil Richard A. , Warheit Kenneth I.
Published: September 2014

Cougar (Puma concolor) hunting has been classified typically as either selective‐hunting with the aid of dogs or nonselective‐hunting without dogs; this is based on the assumption that hunters using dogs to tree cougars can better identify sex of cougars prior to harvest. Subsequent to hunt activity, 94% of all wildlife agencies that allow cougar hunting have mandatory inspections where sex is identified and recorded by agency staff. To test the ability of hunters and agency staff in Washington, USA, to correctly identify sex of cougars in the field, laboratory analysis of DNA from tissue samples collected by experienced hound handlers using biopsy darts and collected during staff inspection of mortalities, respectively, was compared with visual identification and used to determine error rates. The sex assigned by dog hunters in the field matched sex from DNA analysis 70% of the time (n = 159); correct identification varied between 57% and 88%/year. The sex identified by agency staff during inspection of mortalities matched DNA analysis 87% of the time (n = 1,329); correct identification varied between 71% and 90%/year. Because sex misclassification has the potential to alter intended harvest as well as assessing success of management prescriptions, agencies may want to initiate education programs internally and outside their agency. The majority of states and provinces already have mandatory inspections; therefore, agencies would benefit from initiating DNA collection during mandatory inspections to identify error rates of sex identification by staff within their jurisdiction. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Divalent Copper Selenate Complex: Two Types of Octahedral Coordination in the Unit Cell and Disordered 1,4‐Diazabicyclo[2.2.2]octane
Authors: Rekik Walid , Loulou Nkhili Nouha , Naïli Houcine , Dahaoui Slimane
Published: September 2014

The new hybrid compound (C6H14N2)[Cu(H2O)6][Cu(SeO4)2(H2O)4]2 crystallizes in the monoclinic system, space group P21/n, with the unit cell parameters: a = 7.2469(2) Å, b = 9.5360(2) Å, c = 22.1919(5) Å, and β = 95.789(2)°. The structure was solved by conventional direct methods. The R and wR values for 76142 measured reflections were 0.0337 and 0.0625, respectively. Within the structure of this new compound, the transition metal adopts two types of octahedral coordination. Indeed, Cu1 is coordinated by four water molecules and two selenate groups to form the tetraaquadiselenatocuprate(II) anion [Cu(SeO4)2(H2O)4]2–, whereas Cu2 adopts another octahedral environment formed by six water molecules, but three of them crystallographically independent. The Cu1 and Cu2 atoms display the so‐called (4+1+1) and (4+2) type of coordination, respectively, that has often been observed in other compounds containing the same transition metal, which is consistent with a Jahn‐Teller distortion. The crystal structure of the title complex consists of isolated metallic polyhedra and disordered dabcodiium cations linked together by two types of hydrogen bond, OW–H···O and N–H···O, only. The thermogravimetric analysis shows that the dehydration of the compound takes place in four steps. The decomposition leads to the copper oxide in the last stage.
Thermochemistry and Chemical Vapor Transport of In2M3O12 (M = Mo, W)
Authors: Steiner Udo , Schmidt Marcus , Schnelle Walter
Published: September 2014

The standard entropy of compounds In2M3O12 (M = Mo, W) were determined to be S°298 = 390 ± 6 (M = Mo] and S°298 = 404 ± 6 J·mol–1·K–1 (M = W). The entropies of formation from the binary oxides are ΔS°R, 298 = 52 J·mol–1·K–1 (M = Mo] and ΔS°R, 298 = 72 J·mol–1·K–1 (M = W). Both compounds possess positive enthalpies of formation from the oxides at 298 K and are entropically stabilized. Transition enthalpies of the monoclinic to orthorhombic phase transition were measured for In2M3O12 by differential scanning calorimetry. Crystals of In2M3O12 (size up to a few mm) were deposited by means of chemical vapor transport along a temperature gradient ΔT = 100 K using transport agent chlorine. Deposition rates are between 0.2 and about 15 mg·h–1, depending on mean transport temperature and amount of chlorine. Experimental results were compared to predictions by means of thermodynamic modelling. A detailed analysis of the chemical vapor transport behavior was carried out regarding gaseous compounds involved in the transport process, dominant transport reactions and influence of moisture content.
Comparison of body temperature readings between an implantable microchip and a cloacal probe in lorikeets (Trichoglossus haematodus sp.)
Authors: Hoskinson Christine , McCain Stephanie , Allender Matthew C.
Published: September 2014

Body temperature readings can be a useful diagnostic tool for identifying the presence of subclinical disease. Traditionally, rectal or cloacal thermometry has been used to obtain body temperatures. The use of implantable microchips to obtain these temperatures has been studied in a variety of animals, but not yet in avian species. Initially, timepoint one (T1), nine lorikeets were anesthetized via facemask induction with 5% isoflurane and maintained at 2–3% for microchip placement and body temperature data collection. Body temperature was measured at 0 and 2 min post‐anesthetic induction both cloacally, using a Cardell veterinary monitor and also via implantable microchip, utilizing a universal scanner. On two more occasions, timepoints two and three (T2, T3), the same nine lorikeets were manually restrained to obtain body temperature readings both cloacally and via microchip, again at minutes 0 and 2. There was no statistical difference between body temperatures, for both methods, at T1. Microchip temperatures were statistically different than cloacal temperatures at T2 and T3. Body temperatures at T1, were statistically different from those obtained at T2 and T3 for both methods. Additional studies are warranted to verify the accuracy of microchip core body temperature readings in avian species. Zoo Biol. 33:452–454, 2014. © 2014 Wiley Periodicals Inc.
Resection Margin Clearance in Pancreatic Cancer After Implementation of the Leeds Pathology Protocol (LEEPP): Clinically Relevant or Just Academic?
Authors: Gebauer Florian , Tachezy Michael , Vashist Yogesh K. , Marx Andreas H. , Yekebas Emre , Izbicki Jakob R. , Bockhorn Maximilian
Published: September 2014

Background and objectives

The aim of this study was to assess the overall survival (OS) after R0/R1 resections in patients with pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head after implementation of a standardized histopathologic protocol (Leeds Pathology Protocol, LEEPP).

Methods

One hundred and twenty‐five patients underwent surgical resection because of PDAC of the pancreatic head. Patients were histopathologically examined according to a standardized protocol. Their oncologic outcome and clinicopathologic data were compared with those of a patient group before implementation of the LEEPP (n = 116).

Results

The R1 rate increased significantly from 13 to 52 %. There was no significant difference in OS between R0 and R1 resections. The median OS in patients with a tumor clearance of less than 2 mm from the resection margin was 15.1 months (12.1–18.1 months) versus 22.2 months (7.8–36.7 months) (P = 0.046). Multivariate analysis revealed a margin clearance or 2 mm and more as an independent prognosticator for OS.

Conclusions

With applying the LEEPP, there was still no significant correlation between the R‐status and OS in patients with PDAC. However, since a margin clearance of 2 mm or more is a predictive factor for OS, the R1 definition might have to be adapted in PDAC.
Populism, Persistent Republicanism and Declinism: An Empirical Analysis of Populism as a Thin Ideology
Authors: Elchardus Mark , Spruyt Bram
Published: September 2014

Populism is usually studied by looking at the electoral and rhetorical strategies of parties considered to be populist. In contrast, this article attempts to measure the support for the core propositions of populism among voters and explain the social differences in that support. On the basis of a survey of the Dutch-speaking population of Belgium (N: 2,330) we find that this support for populism turns out not to be directly influenced by a weak or uncertain economic position, by dissatisfaction with personal life or feelings of anomie. Support for populism appears foremost as a consequence of a very negative view of the evolution of society – declinism – and of the feeling of belonging to a group of people that is unfairly treated by society.
A scoping review of the literature on the involvement of service users in personality disorder services
Authors: Montgomery L. , Donnelly M.
Published: September 2014

Background

Service user involvement is receiving increasing support from mental health policy makers, service planners and research commissioners. However, we lack a good understanding of the nature and extent to which service users are involved in personality disorder (PD) services and the effects of involvement in these services.

Objectives

To review and appraise published sources; increase understanding about service user involvement in PD services; and highlight knowledge gaps and related issues.

Methods

A scoping review methodology was adopted. Data were ‘charted’ to illustrate the landscape of writings and views and a qualitative analysis synthesized the results in terms of key emergent themes.

Results

Only a small amount of published work was identified with significant gaps in the literature. Effects were reported mostly in terms processes and emotional and practical benefits for service users. Emergent themes were wellness and health, recruitment and support for service users.

Conclusions

This scoping review uncovered a lack of published work despite service user involvement being a key strand of health policy. There is a need for outcomes-focused research regarding service user involvement. Successful user involvement in PD services requires attention to be focused on the context, recruitment, support and ‘wellness’ of service users.
Oat β-glucan: physico-chemical characteristics in relation to its blood-glucose and cholesterol-lowering properties
Authors: Wang Qi , Ellis Peter R.
Published: September 2014

The water-soluble, mixed-linkage β-glucan, a form of soluble dietary fibre, is considered the main biologically active component responsible for the capacity of many oat products to lower postprandial glycaemia and fasting plasma cholesterol in human subjects. The present review discusses the physical and chemical properties of oat β-glucan that are considered important predictors of these beneficial metabolic effects.In vitromodelling and animal and human studies have provided compelling evidence showing that the ability of oat β-glucan to increase the viscosity of digesta in the gastrointestinal tract (GIT) is a primary determinant of its blood-glucose and cholesterol-lowering properties. Therefore, the chemical structure, molecular weight (MW), the rate and extent of dissolution and solution rheology of oat β-glucan are key factors in determining the physiological function of oat-containing foods. The structure and properties of oat β-glucan vary between species and varieties of oats, and are also affected by the growing and storage conditions and processing of oat grain. In addition, the extraction and analysis methods may also contribute to the variations in the structure, MW, hydration and solution rheology of β-glucan obtained from different laboratories. Recent work has demonstrated that β-glucan solubility in foods depends on the source of the material and processing conditions; solubility may also be subject to changes during food preparation and storage (such as freezing). In conclusion, both the amount and MW of β-glucan that are solubilised in the GIT need to be considered when assessing the blood-glucose and cholesterol-lowering properties of oat-containing foods.
Beyond nutrition and agriculture policy: collaborating for a food policy
Authors: Stewart Derek , Kennedy Anne , Pavel Anthony
Published: September 2014

Global interest in food policy is emerging in parallel with mounting challenges to the food supply and the rising prevalence of diet-related chronic health conditions. Some of the foundational elements of food policies are agricultural practices, finite resources, as well as economic burdens associated with a growing and ageing population. At the intersection of these interests is the need for policy synchronisation and a better understanding of the dynamics within local, regional and national government decision-making that ultimately affect the wellness of the populous and the safety, quality, affordability and quantity of the food supply. Policies, synchronised or not, need to be implemented and, for the food industry, this has seen a myriad of approaches with respect to condensing complex nutritional information and health claims. These include front and/or back of pack labelling, traffic light systems, etc. but in general there is little uniformity at the more regional and global scales. This translation of the nutritional and health-beneficial messages accompanying specific products to the consumer will undoubtedly be an area of intense activity, and hopefully interaction with policy makers, as the food industry continues to become a more global industry.
FAMILIES' RESPONSE TO AIDS: NEW INSIGHTS INTO PARENTAL ROLES IN FOSTERING HIV/AIDS KNOWLEDGE
Authors: DIMBUENE ZACHARIE TSALA
Published: September 2014

Worldwide, there is a consensus that parents must be involved in children's HIV/AIDS education. However, there is little evidence that speaks to this advocacy for improving adolescent health. This study developed and tested four hypotheses about (i) the relationship between parents' and adolescents' knowledge of HIV/AIDS transmission routes and prevention strategies conditional upon (ii) parents' gender, (iii) communication about sexuality, and (iv) the parent–adolescent education gap. The sample consisted of 306 parent–adolescent dyads from the 2002 Cameroon Family and Health Survey. Adolescents were aged 12–19 years. Overall, fifteen items about HIV/AIDS transmission routes and prevention strategies were analysed. Descriptive results showed that parents fared better than adolescents regardless of the AIDS fact considered. An exception was the correct use of condoms (parents 57% vs adolescents 61%). The generation gap probably explains this result: parents are more conservative, reluctant and distant from condoms compared with adolescents, who are more receptive and open to discussing sex with peers. Multivariate ordered logistic regressions showed a significant positive effect of parents' HIV/AIDS knowledge on adolescents' HIV/AIDS knowledge, thus supporting the main hypothesis of direct parental influences. Parent–adolescent communication about sexuality showed positive and significant effects on adolescents' HIV/AIDS knowledge, suggesting an ‘enhancing effect’ when combined with the effect of parents' HIV/AIDS knowledge. Against the background that parents in sub-Saharan Africa do not teach their children about sexuality, the study demonstrated that families can play an important role in HIV/AIDS education. These findings have major implications for HIV/AIDS interventions involving adolescents, parents or both, in fostering accurate HIV/AIDS knowledge among adolescents, which could lead to protective sexual behaviours.
Constitutional, Criminal, Civil
Authors: Orren Karen
Published: September 2014

With a view to elaborating a developmental theory of constitutionalism in the United States, this essay explores the relationship among constitutional, criminal, and civil law. It supports, with relevant case materials, a single proposition: civil litigants are afforded contested constitutional protections in federal court to the extent that the judges attribute an aspect of criminality to the underlying facts or issues in question. The essay tests this proposition in the areas of punitive damages, double jeopardy, and constitutional torts; discusses the mirroring of the stipulated pattern in legal maneuvering on constitutional issues; and briefly spells out its implications for the larger theory.
Combined Use of Optical Imaging Satellite Data and Electronic Intelligence Satellite Data for Large Scale Ship Group Surveillance
Authors: Sun Hao , Zou Huanxin , Ji Kefeng , Zhou Shilin , Lu Chunyan
Published: September 2014

We propose a novel framework for large-scale maritime ship group surveillance using spaceborne optical imaging satellite data and Electronic Intelligence (ELINT) satellite data. Considering that the size of a ship is usually less than the distance between different ships for large-scale maritime surveillance, we treat each ship as a mass point and ship groups are modelled as point sets. Motivated by the observation that ship groups performing tactical or strategic operations often have a stable topology and their attributes remain unchanged, we combine both topological features and attributive features within the framework of Dempster-Shafer (D-S) theory for coherent ship group analysis. Our method has been tested using different sets of simulated data and recorded data. Experimental results demonstrate our method is robust and efficient for large-scale maritime surveillance.
Managing uncertainty in potential supplier identification
Authors: Ye Yun , Jankovic Marija , Kremer Gül E. , Bocquet Jean-Claude
Published: September 2014

As a benefit of modularization of complex systems, original equipment manufacturers (OEMs) can choose suppliers in a less constricted way when faced with new or evolving requirements. However, new suppliers usually add uncertainties to the system development. Because suppliers are tightly integrated into the design process in modular design and therefore greatly influence the outcome of the OEM's products, the uncertainty along with requirements satisfaction of the suppliers and their modules should be controlled starting from potential supplier identification. In addition, to better satisfy new requirements, the potential supplier identification should be combined with architecture generation to enable the new technology integration. In this paper, we propose the Architecture & Supplier Identification Tool, which generates all possible architectures and corresponding suppliers based on new requirements through matrix mapping and propagation. Using the Architecture & Supplier Identification Tool, the overall uncertainty and requirements satisfaction of generated architectures can be estimated and controlled. The proposed method aims at providing decision support for early design of complex systems, thereby helping OEMs have an integrated view of suppliers and system architectures in requirements satisfaction and overall uncertainty.
An evidence-based method for examining and reporting cognitive processes in nutrition research
Authors: Pase Matthew P. , Stough Con
Published: September 2014

Cognitive outcomes are frequently implemented as endpoints in nutrition research. To reduce the number of statistical comparisons it is commonplace for nutrition researchers to combine cognitive test results into a smaller number of broad cognitive abilities. However, there is a clear lack of understanding and consensus as to how best execute this practice. The present paper reviews contemporary models of human cognition and proposes a standardised, evidence-based method for grouping cognitive test data into broader cognitive abilities. Both Carroll's model of human cognitive ability and the Cattell–Horn–Carroll (CHC) model of intelligence provide empirically based taxonomies of human cognition. These models provide a cognitive ‘map’ that can be used to guide the handling and analysis of cognitive outcomes in nutrition research. Making use of a valid cognitive nomenclature can provide the field of clinical nutrition with a common cognitive language enabling efficient comparisons of cognitive outcomes across studies. This will make it easier for researchers, policymakers and readers to interpret and compare cognitive outcomes for different interventions. Using an empirically derived cognitive nomenclature to guide the creation of cognitive composite scores will ensure that cognitive endpoints are theoretically valid and meaningful. This will increase the generalisability of trial results to the general population. The present review also discusses how the CHC model of cognition can also guide the synthesis of cognitive outcomes in systematic reviews and meta-analysis.
Household participation in a Payments for Environmental Services programme: the Nhambita Forest Carbon Project (Mozambique)
Authors: Hegde Ravi , Bull Gary Q. , Wunder Sven , Kozak Robert A.
Published: September 2014

Quantitative research on household participation in the Payments for Environmental Services (PES) programme remains scarce. This paper aims to determine the key factors influencing household participation in a PES programme in Mozambique. Questionnaire-based quarterly surveys were conducted with 290 randomly selected households. We used the instrumental variables technique to identify the factors influencing household participation. The instrumental variables used for forest dependence were: household head born in the village, duration of residence of the household head in the village, ethnicity of the household head, business ownership of the household head and off-farm income of the household. The results show that education of household head and households' trust towards community members positively influenced household participation in PES, while forest dependence influenced it negatively. Future PES projects may thus need to focus more on developing social capital and the resource dependence of households.
The Judge in the Mirror: Kant on Conscience
Authors: Vujošević Marijana
Published: September 2014

Kant’s conception of conscience has been relatively neglected by Kant scholars and the secondary literature offers no explanation of whether (and if so, how) his treatments of conscience fit together. To achieve a fuller understanding of Kant’s general position on conscience, I question the widespread assumption that conscience is a feeling and account for the nature of conscience and its multiple functions. On my reading, conscience is ‘the internal judge’ whose verdict triggers certain emotional reactions. Through the moral self-evaluative activities of this inner judge, we come to know our character better. In the judgements of conscience, we take account of various psychological conditions while judging both whether these conditions stand in the way of our establishing moral maxims and whether we hold ourselves accountable for our actions. By arousing certain feelings, these judgements also move us to moral action.
WHEN WORDS UNINTENTIONALLY WOUND: A DUTY TO SELF-CENSOR
Authors: Tallman Ruth
Published: September 2014

Based on Robert Baker's metaphorical view of damaging language, I argue that morally responsible individuals are obligated to refrain from using the word ‘gay’ as a negative adjective directed towards that which the speaker dislikes. According to the metaphorical view, while a speaker may understand her use of the word ‘gay’ as devoid of homosexual connotations, the hearer – particularly a young person still coming to understand his own sexuality – is likely to conclude that his ‘gayness’ puts him in the same hated category as all of those other objects, events, and persons who are negatively called ‘gay’.
Influence of grazing and land use on stream-channel characteristics among small dairy farms in the Eastern United States
Authors: Brand Genevieve , Vondracek Bruce , Jordan Nicholas R.
Published: September 2014

Rotational grazing (RG) is a livestock management practice that rotates grazing cattle on a scale of hours to days among small pastures termed paddocks. It may beneficially affect stream channels, relative to other livestock management practices. Such effects and other beneficial effects on hydrology are important to RG's potential to provide a highly multifunctional mode of livestock farming. Previous comparisons of effects of RG and confinement dairy (CD) on adjoining streams have been restricted in scale and scope. We examined 11 stream-channel characteristics on a representative sample of 37 small dairy farms that used either RG or CD production methods. Our objectives were: (1) to compare channel characteristics on RG and CD farms, as these production methods are implemented in practice, in New York, Pennsylvania and Wisconsin, USA; and (2) to examine land use on these farms that may affect stream-channel characteristics. To help interpret channel characteristic findings, we examined on-farm land use in riparian areas 50 m in width along both sides of stream reaches and whole-farm land use. In all states, stream-channel characteristics on RG and CD farms did not differ. Whole-farm land use differed significantly between farm types; CD farms allocated more land to annual row crops, whereas RG farms allocated more land to pasture and grassland. However, land cover in 50 m riparian areas was not different between farm types within states; in particular, many RG and CD farms had continuously grazed pastures in riparian areas, typically occupied by juvenile and non-lactating cows, which may have contributed sediment and nutrients to streams. This similarity in riparian management practices may explain the observed similarity of farm types with respect to stream-channel characteristics. To realize the potential benefits of RG on streams, best management practices that affect stream-channel characteristics, such as protection of riparian areas, may improve aggregate effects of RG on stream quality and also enhance other environment, economic and social benefits of RG.
Problems of Interaction Between the International and Domestic Legal Orders
Authors: OWADA Hisashi
Published: September 2014

With the rapid advent of globalization, international law has come to expand into new areas which had traditionally been under the exclusive domain of municipal law. As a result, problems concerning interaction between the international and domestic legal orders have become increasingly common. Specifically, difficulties have arisen concerning the implementation of international law decisions into the domestic legal order. This paper examines this problem in three different areas: the process of incorporation of international treaties into the domestic legal order; the issue of giving effect to Security Council resolutions in domestic law; and the issue of the implementation within the domestic legal system of judgments of international courts and tribunals. The paper concludes that, in an age of the emergence of a global community as a matter of socioeconomic reality, the two legal orders should work together to promote common public policy, paying due respect to the decisions of international institutions.
Keeping the immune system in check: a role for mitophagy
Authors: Lazarou Michael
Published: September 2014

Mitochondria play a central role in many facets of cellular function including energy production, control of cell death and immune signaling. Breakdown of any of these pathways because of mitochondrial deficits or excessive reactive oxygen species production has detrimental consequences for immune system function and cell viability. Maintaining the functional integrity of mitochondria is therefore a critical challenge for the cell. Surveillance systems that monitor mitochondrial status enable the cell to identify and either repair or eliminate dysfunctional mitochondria. Mitophagy is a selective form of autophagy that eliminates dysfunctional mitochondria from the population to maintain overall mitochondrial health. This review covers the major players involved in mitophagy and explores the role mitophagy plays to support the immune system.
Kupfer‐type immunological synapses in vivo: Raison D’être of SMAC
Authors: Mitxitorena Izaskun , Saavedra Elena , Barcia Carlos
Published: September 2014

T cells engage with antigen‐presenting cells to form immunological synapses. These intimate contacts are characterized by the complex arrangement of molecules at the intercellular interface, which has been described as the supramolecular activation cluster (SMAC). However, due to T cells functioning without SMAC formation and the difficulties of studying these complex arrangements in vivo, its biological importance has been questioned. In light of recent data, we focus this review on the putative functionality of SMACs in T‐cell synaptic contacts in vivo and emphasize the therapeutic potential of SMAC manipulation in immune‐driven diseases.
Enzymatic fingerprinting of structurally similar homologous proteins using polyion complex library constructed by tuning PEGylated polyamine functionalities
Authors: Tomita Shunsuke , Soejima Tomohiro , Shiraki Kentaro , Yoshimoto Keitaro
Published: September 2014

Structurally similar homologous albumins were fingerprinted and discriminated by a sensor array consisting of a polyion complex library with artificial differentiation constructed by facile tuning of PEGylated polyamine functionalities.
A “light-on” colorimetric assay for anion detection using the inhibitory effect of anions on the catalytic activity of metal nanoparticles for the degradation of methyl orange
Authors: Lu Lixia , Yang Fan , Yang Xiurong
Published: September 2014

A “light-on” colorimetric method for anion detection using the catalytic ability of metal nanoparticles for methyl orange (MO) degradation was developed.
A flow injection low-pressure chromatographic system exploiting fused-core columns
Authors: Batista Alex D. , Rocha Fábio R. P.
Published: September 2014

The first use of fused-core columns for low-pressure chromatographic separations in a flow injection system.
A single-chain magnet based on linear [MnIII2MnII] units
Authors: Papatriantafyllopoulou Constantina , Zartilas Sotiris , Manos Manolis J. , Pichon Céline , Clérac Rodolphe , Tasiopoulos Anastasios J.
Published: September 2014

The synthesis, structure and single-chain magnet properties of a unique one-dimensional coordination polymer based on a linear mixed valent [MnIII2MnII] repeating unit are described.
Three-dimensional spider-web architecture assembled from Na2Ti3O7 nanotubes as a high performance anode for a sodium-ion battery
Authors: Zhang Yuping , Guo Lin , Yang Shihe
Published: September 2014

Na inserted/extracted into/from spider web-like architectures assembled from Na2Ti3O7 nanotubes behave as natural spiders feeding on themselves.
The role of lattice parameter in water adsorption and wetting of a solid surface
Authors: Massey A. , McBride F. , Darling G. R. , Nakamura M. , Hodgson A.
Published: September 2014

Reducing the lattice parameter of a Sn–metal surface alloy below the O–O separation of ice disrupts the flat wetting layer, causing the first layer to buckle and instead form ice clusters.
Structure and conformational analysis of the anti-HIV reverse transcriptase inhibitor AZT using MP2 and DFT methods. Differences with the natural nucleoside thymidine. Simulation of the 1st phosphorylation step with ATP
Authors: Palafox M. Alcolea
Published: September 2014

A proton-transfer mechanism is proposed for the first phosphorylation step of the nucleoside HIV-1 reverse transcriptase inhibitor AZT (3′-azido-3′ deoxythymidine) by interacting with ATP.
Assessing the impact of anion–π effects on phenylalanine ion structures using IRMPD spectroscopy
Authors: Burt Michael , Wilson Kathleen , Marta Rick , Hasan Moaraj , Scott Hopkins W. , McMahon Terry
Published: September 2014

The gas-phase structures of two halide-bound phenylalanine anions (PheX−, X = Cl− or Br−) and five fluorinated derivatives have been identified using infrared multiple photon dissociation (IRMPD) spectroscopy.
Optical and magnetic properties of Ba5(BO3)3F single crystals
Authors: Yelisseyev A. P. , Jiang Xingxing , Solntsev V. P. , Bekker T. B. , Lin Zheshuai
Published: September 2014

The optical properties of Ba5(BO3)3F as a bulk single crystal are investigated experimentally and theoretically.
Visually tolerable tiling (VTT) for making a large-area flexible patterned surface
Authors: Kwak Moon Kyu , Ok Jong G. , Lee Sung Ho , Guo L. Jay
Published: September 2014

Large-area micro/nano-patterns on a flexible substrate were produced using the VTT (visually tolerable tiling) method, realizing invisible seam lines between small master tiles. This could be applied in the roll-to-roll imprinting process, producing large-area polarizers and microprism sheets without visible seam lines.
Development of a chemically sensitive online SEC detector based on FTIR spectroscopy
Authors: Beskers Timo F. , Hofe Thorsten , Wilhelm Manfred
Published: September 2014

A new FTIR–SEC coupling method provides correlated information about the molecular weight distribution and the chemical composition and has the potential to be applied as a standard SEC detector.
Effects of rare earth adsorption on electronic structure and optical properties in β-Si3N4 ceramics from first principles
Authors: Wei Yin , Wang Hongjie , Lu Xuefeng , Wen Jiangbo , Niu Min , Fan Xingyu , Jia Shuhai
Published: September 2014

Electronic structure and optical properties of silicon nitride adsorbed by rare earths are explored by density functional theory.
Fluorescent bionanoprobes based on quantum dot-chitosan–O-phospho-l-serine conjugates for labeling human bone marrow stromal cells
Authors: Salgado Christiane L. , Mansur Alexandra A. P. , Mansur Herman S. , Monteiro Fernando J. M.
Published: September 2014

Fluorescent biocompatible quantum dots functionalized with chitosan–O-phospho-l-serine nanoconjugates were synthesized and characterized for targeting and labeling human bone marrow stromal cells.
Adaptive sampling strong tracking scaled unscented Kalman filter for denoising the fibre optic gyroscope drift signal
Authors: Narasimhappa Mundla , Sabat Samrat L. , Nayak Jagannath
Published: September 2014

The interferometric fibre optic gyroscope (IFOG) is a kernel component of strap down inertial navigation system (SINS) for providing angular rotation of any moving object. The behaviour of SINS degrades because of noise and random drift errors of the IFOG sensor. This study proposes a hybrid of adaptive sampling strong tracking algorithm (ASSTA) and scaled unscented Kalman filter algorithm for denoising the IFOG signal. In this algorithm, the state error covariance (P) is updated by using a suboptimal fading factor based on the innovation sequence followed by the ASSTA method. The proposed algorithm is applied for denoising the IFOG signal under static and dynamic environment to crush the random drift errors and noises. Allan variance analysis is used for analysing the efficiency of algorithms. Simulation results depict that the suggested algorithm is suitable for reducing drifts of the gyro signal.
Development of an alternating integrator for magnetic measurements for experimental advanced superconducting tokamak
Authors: Liu D. M. , Wan B. N. , Zhao W. Z. , Shen B. , He Y. G. , Chen B. , Huang J. , Liu H. Q.
Published: September 2014

A high-performance integrator is one of the key electronic devices for reliably controlling plasma in the experimental advanced superconducting tokamak for long pulse operation. We once designed an integrator system of real-time drift compensation, which has a low integration drift. However, it is not feasible for really continuous operations due to capacitive leakage error and nonlinearity error. To solve the above-mentioned problems, this paper presents a new alternating integrator. In the new integrator, the integrator system of real-time drift compensation is adopted as one integral cell while two such integral cells work alternately. To achieve the alternate function, a Field Programmable Gate Array built in the digitizer is utilized. The performance test shows that the developed integrator with the integration time constant of 20 ms has a low integration drift (<15 mV) for 1000 s.
Symmetry breaking of magnetic vortices before annihilation
Authors: Pulecio J. F. , Pollard S. D. , Warnicke P. , Arena D. A. , Zhu Y.
Published: September 2014

Magnetic vortices in nanoscopic ferromagnetic elements can be treated as solitons that exhibit static and dynamic stability even above room temperature, making them promising for technological applications. Although their properties at low energy configurations have been well studied, the properties of solitons undergoing structural breakdown are poorly understood. Here, we destabilize the soliton through Zeeman and demagnetization interactions and investigate the symmetry breaking of the magnetic vortex state. Using high-resolution Lorentz imaging and numerical simulations, we observe phase transitions of the core from the characteristic point-like structure into distinct extended asymmetric states differentiated by the polarity. The deformations start at intermediate displacements and are traced until the point of annihilation at the disc's edge. We discuss the use of these asymmetric states as a method to determine the core polarity for in-plane magnetic imaging techniques.
Hydrodynamic anomalies in supercritical fluid
Authors: Ryltsev R. E. , Chtchelkatchev N. M.
Published: September 2014

Using the molecular dynamics simulations we investigate properties of velocity autocorrelation function of Lennard-Jones fluid at long and intermediate time scales in wide ranges of temperature and density. We show that the amplitudes of both the leading and the subleading time asymptotic terms of velocity autocorrelation function, a1 and a2, show essentially non-monotonic temperature and density dependence. There are two lines on temperature-density plain corresponding to maxima of a1 (a2) along isochors and isotherms situated in the supercritical fluid (hydrodynamic anomalies). These lines give insight into the stages of the fluid evolution into gas.
Symmetric structure of field algebra of G-spin models determined by a normal subgroup
Authors: Xin Qiaoling , Jiang Lining
Published: September 2014

Let G be a finite group and H a normal subgroup. D(H; G) is the crossed product of C(H) and \documentclass[12pt]{minimal}\begin{document}${\mathbb {C}}G$\end{document}CG which is only a subalgebra of D(G), the double algebra of G. One can construct a C*-subalgebra \documentclass[12pt]{minimal}\begin{document}${\mathcal {F}}_H$\end{document}FH of the field algebra \documentclass[12pt]{minimal}\begin{document}$\mathcal {F}$\end{document}F of G-spin models, so that \documentclass[12pt]{minimal}\begin{document}${\mathcal {F}}_H$\end{document}FH is a D(H; G)-module algebra, whereas \documentclass[12pt]{minimal}\begin{document}$\mathcal {F}$\end{document}F is not. Then the observable algebra \documentclass[12pt]{minimal}\begin{document}${\mathcal {A}}_{(H,G)}$\end{document}A(H,G) is obtained as the D(H; G)-invariant subalgebra of \documentclass[12pt]{minimal}\begin{document}${\mathcal {F}}_H$\end{document}FH, and there exists a unique C*-representation of D(H; G) such that D(H; G) and \documentclass[12pt]{minimal}\begin{document}${\mathcal {A}}_{(H,G)}$\end{document}A(H,G) are commutants with each other.
Improved repetition rate mixed isotope CO2 TEA laser
Authors: Cohn D. B.
Published: September 2014

A compact CO2 TEA laser has been developed for remote chemical detection that operates at a repetition rate of 250 Hz. It emits 700 mJ/pulse at 10.6 μm in a multimode beam with the 12C16O2 isotope. With mixed 12C16O2 plus 13C16O2 isotopes it emits multiple lines in both isotope manifolds to improve detection of a broad range of chemicals. In particular, output pulse energies are 110 mJ/pulse at 9.77 μm, 250 mJ/pulse at 10 μm, and 550 mJ/pulse at 11.15 μm, useful for detection of the chemical agents Sarin, Tabun, and VX. Related work shows capability for long term sealed operation with a catalyst and an agile tuner at a wavelength shift rate of 200 Hz.
A firmware-defined digital direct-sampling NMR spectrometer for condensed matter physics
Authors: Pikulski M. , Shiroka T. , Ott H.-R. , Mesot J.
Published: September 2014

We report on the design and implementation of a new digital, broad-band nuclear magnetic resonance (NMR) spectrometer suitable for probing condensed matter. The spectrometer uses direct sampling in both transmission and reception. It relies on a single, commercially-available signal processing device with a user-accessible field-programmable gate array (FPGA). Its functions are defined exclusively by the FPGA firmware and the application software. Besides allowing for fast replication, flexibility, and extensibility, our software-based solution preserves the option to reuse the components for other projects. The device operates up to 400 MHz without, and up to 800 MHz with undersampling, respectively. Digital down-conversion with ±10 MHz passband is provided on the receiver side. The system supports high repetition rates and has virtually no intrinsic dead time. We describe briefly how the spectrometer integrates into the experimental setup and present test data which demonstrates that its performance is competitive with that of conventional designs.
A file of red blood cells in tube flow: A three-dimensional numerical study
Authors: Ye Ting , Phan-Thien Nhan , Khoo Boo Cheong , Lim Chwee Teck
Published: September 2014

The rheology of a file of red blood cells (RBCs) in a tube flow is investigated based on a three-dimensional (3D) computational model using the dissipative particle dynamics (DPD) method. The 3D model consists of a discrete RBC model to describe the RBC deformation, a Morse potential model to characterize the cell–cell interaction, and a DPD model to provide all the relevant information on the suspension flow. Three important features of the suspension flow are simulated and analyzed, (i) the effect of the tube hematocrit, (ii) the effect of the cell spacing, and (iii) the effect of the flow velocity. We first study the cell deformation and the rheology of suspension at different tube hematocrit. The results show that the cell deformation decreases with increasing tube hematocrit, and a good agreement between the simulation and available experiments is found for the discharge hematocrit and relative apparent viscosity of RBC suspension. We then analyze the effect of non-uniform cell spacing, where the cell–cell interaction goes into effect, showing that a non-uniform cell spacing has a slight effect on the cell deformation, and almost has no effect on the rheology of suspension. We finally study the effect of the flow velocity and show that a typical plug-flow velocity profile is observed. The results also show that the cell deformation increases with increasing flow velocity, as expected. The discharge hematocrit also increases, but the relative apparent viscosity decreases, with increasing flow velocity.
Improvement of resistive switching performances via an amorphous ZrO2 layer formation in TiO2-based forming-free resistive random access memory
Authors: Zeng Baiwen , Xu Dinglin , Tang Minghua , Xiao Yongguang , Zhou Yuzhou , Xiong Rongxin , Li Zheng , Zhou Yichun
Published: September 2014

We present the effects of an amorphous ZrO2 layer on the TiO2-based bipolar resistive switching memory device where the ZrO2 layer plays an important role as a supplementary reservoir of oxygen vacancies. Compared with Pt/TiO2/Pt monolayer device, a remarkably improved uniformity of switching parameters such as switching voltages and resistances in high/low states is demonstrated in the Pt/ZrO2/TiO2/Pt system. The resistive switching mechanism of memory devices incorporating the ZrO2/TiO2 bilayer structure can be attributed to multiple conducting filaments through the occurrence of redox reactions at the ZrO2/TiO2 surface.
Description of electron transfer in the ground and excited states of organic donor–acceptor systems by single-reference and multi-reference density functional methods
Authors: Filatov Michael
Published: September 2014

Electron transfer in the ground and excited states of a model donor–acceptor (D–A) system is investigated using the single-reference and multi-reference density functional theory (DFT) methods. To analyze the results of the calculations, a simple two-site multi-reference model was derived that predicts a stepwise electron transfer in the S0 state and a wave-like dependence of the S1 electron transfer on the external stimulus. The standard single-reference Kohn-Sham (KS) DFT approach and the time-dependent DFT (TDDFT) method failed to describe the correct dependence of the S0 and S1 electron transfer on the external electric field applied along the donor–acceptor system. The multi-reference DFT approach, the spin-restricted ensemble-referenced KS (REKS) method, was able to successfully reproduce the correct behavior of the S0 and S1 electron transfer on the applied field. The REKS method was benchmarked against experimentally measured gas phase charge transfer excitations in a series of organic donor–acceptor complexes and displayed its ability to describe this type of electronic transitions with a very high accuracy, mean absolute error of 0.05 eV with the use of the standard range separated density functionals. On the basis of the calculations undertaken in this work, it is suggested that the non-adiabatic coupling between the S0 and S1 states may interfere with the electron transfer in a weakly coupled donor–acceptor system. It is also suggested that the electronic excitation of a D+–A− system may play a dual role by assisting the further electron transfer at certain magnitudes of the applied electric field and causing the backward transfer at lower electric field strengths.
Communication: Newton homotopies for sampling stationary points of potential energy landscapes
Authors: Mehta Dhagash , Chen Tianran , Hauenstein Jonathan D. , Wales David J.
Published: September 2014

One of the most challenging and frequently arising problems in many areas of science is to find solutions of a system of multivariate nonlinear equations. There are several numerical methods that can find many (or all if the system is small enough) solutions but they all exhibit characteristic problems. Moreover, traditional methods can break down if the system contains singular solutions. Here, we propose an efficient implementation of Newton homotopies, which can sample a large number of the stationary points of complicated many-body potentials. We demonstrate how the procedure works by applying it to the nearest-neighbor ϕ4 model and atomic clusters.