bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic behavior of the discrete‐time double integrator with saturated locally stabilizing linear state feedback laws
Authors: Yang Tao , Stoorvogel Anton A. , Saberi Ali 
Published: June 2012

SUMMARYThe main contribution of this paper is to completely characterize the dynamic behavior of the discrete‐time double integrator with a saturated locally stabilizing linear state feedback law. In continuous‐time setting, any linear state feedback control law that locally stabilizes the double integrator also globally stabilizes the system in the presence of actuator saturation. In discrete‐time setting, the equivalent of the double integrator does not have the same property. In this paper, we completely characterize the global behavior of saturated locally stabilizing linear state feedback laws for the discrete‐time double integrator. Copyright © 2012 John Wiley & Sons, Ltd.
Quantitative Measurement of the Magnetic Moment of Individual Magnetic Nanoparticles by Magnetic Force Microscopy
Authors: Sievers Sibylle , Braun Kai‐Felix , Eberbeck Dietmar , Gustafsson Stefan , Olsson Eva , Schumacher Hans Werner , Siegner Uwe 
Published: June 2012

AbstractThe quantitative measurement of the magnetization of individual magnetic nanoparticles (MNPs) using magnetic force microscopy (MFM) is described. Quantitative measurement is realized by calibration of the MFM signal using an MNP reference sample with traceably determined magnetization. A resolution of the magnetic moment of the order of 10−18 A m2 under ambient conditions is demonstrated, which is presently limited by the tip's magnetic moment and the noise level of the instrument. The calibration scheme can be applied to practically any magnetic force microscope and tip, thus allowing a wide range of future applications, for example in nanomagnetism and biotechnology.
HEDGEHOG-GLI Signaling Drives Self-Renewal and Tumorigenicity of Human Melanoma-Initiating Cells
Authors: Santini Roberta , Vinci Maria C. , Pandolfi Silvia , Penachioni Junia Y. , Montagnani Valentina , Olivito Biagio , Gattai Riccardo , Pimpinelli Nicola , Gerlini Gianni , Borgognoni Lorenzo , Stecca Barbara 
Published: June 2012

Abstract
The question of whether cancer stem/tumor-initiating cells (CSC/TIC) exist in human melanomas has arisen in the last few years. Here, we have used nonadherent spheres and the aldehyde dehydrogenase (ALDH) enzymatic activity to enrich for CSC/TIC in a collection of human melanomas obtained from a broad spectrum of sites and stages. We find that melanomaspheres display extensive in vitro self-renewal ability and sustain tumor growth in vivo, generating human melanoma xenografts that recapitulate the phenotypic composition of the parental tumor. Melanomaspheres express high levels of Hedgehog (HH) pathway components and of embryonic pluripotent stem cell factors SOX2, NANOG, OCT4, and KLF4. We show that human melanomas contain a subset of cells expressing high ALDH activity (ALDHhigh), which is endowed with higher self-renewal and tumorigenic abilities than the ALDHlow population. A good correlation between the number of ALDHhigh cells and sphere formation efficiency was observed. Notably, both pharmacological inhibition of HH signaling by the SMOOTHENED (SMO) antagonist cyclopamine and GLI antagonist GANT61 and stable expression of shRNA targeting either SMO or GLI1 result in a significant decrease in melanoma stem cell self-renewal in vitro and a reduction in the number of ALDHhigh melanoma stem cells. Finally, we show that interference with the HH-GLI pathway through lentiviral-mediated silencing of SMO and GLI1 drastically diminishes tumor initiation of ALDHhigh melanoma stem cells. In conclusion, our data indicate an essential role of the HH-GLI1 signaling in controlling self-renewal and tumor initiation of melanoma CSC/TIC. Targeting HH-GLI1 is thus predicted to reduce the melanoma stem cell compartment.
FDI and economic activity in Africa: The role of local financial markets
Authors: Adjasi Charles. K. D. , Abor Joshua , Osei Kofi A. , Nyavor‐Foli Ernestine E. 
Published: June 2012

AbstractThis article examines the role local financial markets play in the link between foreign direct investment (FDI) and economic activity. The article uses panel data methods on 32 African countries over the period 1997 to 2008. Our results show that FDI only has a significant effect on economic activity when interacted with financial market variables, namely, private‐sector credit and savings. The results of this study imply that FDI is more productive in the presence of well‐functioning local financial markets. African governments must therefore pay particular attention to developing further local financial markets to ensure full economic benefits of FDI inflows. © 2012 Wiley Periodicals, Inc.
Foreign direct investment and technology transfer policies in Africa: A review of the Ghanaian experience
Authors: Luther Osabutey Ellis , Debrah Yaw A. 
Published: June 2012

AbstractForeign Direct Investment (FDI) into Africa has received research attention in the past two decades, and the flow of FDI into Africa has been on an upsurge. Countries such as Ghana have improved their investment climate to increase FDI attraction. Clamour for FDI has led policy focus toward attraction, with little attention to technology transfer and capacity building. FDI flow, global competitiveness index and tertiary enrollment data are adapted to evaluate technology transfer and capacity building. This article reveals that there is a policy vacuum and/or policy ineptitude: FDI policies are not integrated with education and human capital development policies, technology development policies, technology transfer policies, and private‐sector development policies. © 2012 Wiley Periodicals, Inc.
Foreign direct investment: Technology gap effects on international business capabilities of sub‐Saharan Africa
Authors: Elmawazini Khaled , Nwankwo Sonny 
Published: June 2012

AbstractThis article investigates the impact of foreign direct investment (FDI) on the technology gap between countries in sub‐Saharan Africa (SSA) and the Organisation for Economic Co‐operation and Development (OECD), against the backdrop of relatively weak industrial performance of SSA. OECD is used in order to measure how SSA's competitiveness compares with the more advanced economies. The article further examines how the technology gap, in turn, exacerbates international business capabilities of SSA and draws out some policy implications. Using a panel data regression model, the article finds that FDI inflows have had relatively little impact on SSA's industrial capacity development and global competitiveness, and, indeed, widened the gap between SSA and major developed economies. © 2012 Wiley Periodicals, Inc.
Challenges of microfinance accessibility by SMEs in Tanzania
Authors: Woldie Atsede , Isaac Mwita John , Saidimu Joyce 
Published: June 2012

AbstractThis article is based on a research exploring the challenges of microfinance accessibility by SMEs in Tanzania. A survey research methodology is adopted utilizing primary and secondary data from a purposively selected sample of SME operators. Data is collected using questionnaires and interviews which are analysed using SPSS Statistics 17.0. The evidence gathered show that the financial sector has failed to adequately extend microfinance facilities to SMEs due to high transaction costs, lack of collaterals, inadequate skills in developing and managing bankable projects. The study concludes that where default‐risk is perceived to be high, microinsurance must be taken by applicants as collateral. The article recommends initiation of intervention policies, which will uphold sustainability of SMEs and streamline accessibility to microfinance. Finally, the authors look at action‐focused solutions to support and build on the potential of public equity markets to help SMEs access microfinance as an area for further studies. © 2012 Wiley Periodicals, Inc.
Financial literacy among the educated: An exploratory study of selected university students in South Africa
Authors: Shambare Richard , Rugimbana Robert 
Published: June 2012

AbstractThe challenges associated with financial illiteracy are increasingly becoming a topical issue. Consequently, there is a growing body of literature explaining the antecedents and consequents of financial illiteracy. While most of these studies report on the experience from the developed world, very little is known on the subject matter in emerging economies. This study attempts to address this paucity in the body of knowledge by investigating the nature and extent of financial literacy in South Africa. Given that the literature acknowledges that financial illiteracy is a problem faced across the entire spectrum of society, including the uneducated and the educated, this study investigates financial illiteracy among university students, a section of the South African population that could be classified as being educated. A self‐administered financial literacy scale was administered to a sample of 214 students from a large South African metropolitan university. Overall, results indicate moderate levels of financial illiteracy; suggesting that even among the educated, there is a need to reinforce basic financial concepts. Some implications for financial service providers in interacting with literate consumers who may be financially illiterate are provided. © 2012 Wiley Periodicals, Inc.
Exploring children, family, and consumption behavior: Empirical evidence from Nigeria
Authors: Gbadamosi Ayantunji 
Published: June 2012

AbstractMultinational enterprises, especially those in the fast‐moving consumer goods market, have long been concerned with the dynamics of family‐oriented consumption behavior. What is little known is the changing locus of power as children assume more power in family buying decisions. This paper adopts qualitative methods to address the changing role of children, strategies applied to influence family purchases, cultural shifts, and the implications for international business. Nigeria is used as a contextual base but the implications of the study could span sub‐Saharan African region. © 2012 Wiley Periodicals, Inc.
Spin‐component‐scaled electron correlation methods
Authors: Grimme Stefan , Goerigk Lars , Fink Reinhold F. 
Published: June 2012

AbstractSpin‐component‐scaled (SCS) electron correlation methods for electronic structure theory are reviewed. The methods can be derived theoretically by applying special conditions to the underlying wave functions in perturbation theory. They are based on the insight that low‐order wave function expansions treat the correlation effects of electron pairs with opposite spin (OS) and same spin (SS) differently because of their different treatment at the underlying Hartree–Fock level. Physically, this is related to the different average inter‐electronic distances in the SS and OS electron pairs. The overview starts with the original SCS‐MP2 method and discusses its strengths and weaknesses and various ways to parameterize the scaling factors. Extensions to coupled‐cluster and excited state methods as well the connection to virtual‐orbital dependent density functional approaches are highlighted. The performance of various SCS methods in large thermochemical benchmarks and for excitation energies is discussed in comparison with other common electronic structure methods.This article is categorized under:

Electronic Structure Theory > Ab Initio Electronic Structure Methods
Objective function‐based clustering
Authors: Hall Lawrence O. 
Published: June 2012

AbstractClustering is typically applied for data exploration when there are no or very few labeled data available. The goal is to find groups or clusters of like data. The clusters will be of interest to the person applying the algorithm. An objective function‐based clustering algorithm tries to minimize (or maximize) a function such that the clusters that are obtained when the minimum/maximum is reached are homogeneous. One needs to choose agoodset of features and the appropriate number of clusters to generate a good partition of the data into maximally homogeneous groups. Objective functions for clustering are introduced. Clustering algorithms generated from the given objective functions are shown, with a number of examples of widely used approaches discussed. © 2012 Wiley Periodicals, Inc.This article is categorized under:Algorithmic Development > Scalable Statistical MethodsAlgorithmic Development > Structure DiscoveryTechnologies > Machine LearningTechnologies > Structure Discovery and Clustering
Knowledge discovery for scheduling in computational grids
Authors: Fölling Alexander , Lepping Joachim 
Published: June 2012

AbstractScheduling in computational grids addresses the allocation of computing jobs to globally distributed compute resources. In a frequently changing resource environment, scheduling decisions have to be made rapidly. Depending on both the job properties and the current state of the resources, those decisions are different. Thus, the performance of grid scheduling systems highly depends on their adaptivity and flexibility in changing environments. Under these conditions, methods from knowledge discovery yielded significant success to augment and substitute conventional grid scheduling techniques. This paper presents a survey on approaches to extract, represent, and utilize knowledge to improve the grid scheduling performance. It aims to give researchers insight into techniques used for knowledge‐supported scheduling in large‐scale distributed computing environments. © 2012 Wiley Periodicals, Inc.This article is categorized under:

Application Areas > Science and Technology
Technologies > Machine Learning
Technologies > Prediction
Knowledge discovery interestingness measures based on unexpectedness
Authors: Kontonasios Kleanthis‐Nikolaos , Spyropoulou Eirini , De Bie Tijl 
Published: June 2012

AbstractKnowledge discovery methods often discover a large number of patterns. Although this can be considered of interest, it certainly presents considerable challenges too. Indeed, this set of patterns often contains lots of uninteresting patterns that risk overwhelming the data miner. In addition, a single interesting pattern can be discovered in a multitude of tiny variations that for all practical purposes are redundant. These issues are referred to as the pattern explosion problem. They lie at the basis of much recent research attempting to quantify interestingness and redundancy between patterns, with the purpose of filtering down a large pattern set to an interesting and compact subset. Many diverse approaches to interestingness and corresponding interestingness measures (IMs) have been proposed in the literature. Some of them, named objective IMs, define interestingness only based on objective criteria of the pattern and data at hand. Subjective IMs additionally depend on the user's prior knowledge about the dataset. Formalizing unexpectedness is probably the most common approach for defining subjective IMs, where a pattern is deemed unexpected if it contradicts the user's expectations about the dataset. Such subjective IMs based on unexpectedness form the focus of this paper. We categorize measures based on unexpectedness into two major subgroups, namely, syntactical and probabilistic approaches. Based on this distinction, we survey different methods for assessing the unexpectedness of patterns with a special focus on frequent itemsets, tiles, association rules, and classification rules. © 2012 Wiley Periodicals, Inc.This article is categorized under:

Algorithmic Development > Association Rules
Algorithmic Development > Statistics
Phase‐shift, stimuli‐responsive perfluorocarbon nanodroplets for drug delivery to cancer
Authors: Rapoport Natalya 
Published: June 2012

AbstractThis review focuses on phase‐shift perfluorocarbon nanoemulsions whose action depends on an ultrasound‐triggered phase shift from a liquid to gas state. For drug‐loaded perfluorocarbon nanoemulsions, microbubbles are formed under the action of tumor‐directed ultrasound and drug is released locally into tumor volume in this process. This review covers in detail mechanisms involved in the droplet‐to‐bubble transition as well as mechanisms of ultrasound‐mediated drug delivery.WIREs Nanomed Nanobiotechnol2012, 4:492–510. doi: 10.1002/wnan.1176This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging TechnologiesTherapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Primary ovarian insufficiency in classic galactosemia: role of FSH dysfunction and timing of the lesion
Authors: Gubbels Cynthia S. , Land Jolande A. , Evers Johannes L. H. , Bierau Jörgen , Menheere Paul P. C. A. , Robben Simon G. F. , Rubio‐Gozalbo M. Estela 
Published: June 2012

AbstractFSH inactivity due to secondary hypoglycosylation has been suggested as a potential mechanism for primary ovarian insufficiency in classic galactosemia. To investigate the role of FSH and to gain insight in the timing of the damage, ovarian stimulation tests were performed and data on ovarian imaging collected. Fifteen patients with primary ovarian insufficiency underwent ovarian stimulation with gonadotropins. Only one patient showed a normal increase in estradiol level, all the others had a low or no estradiol response. Anti‐Müllerian hormone measurement in all girls and women showed levels below the detection limit of 0.10 μg/l. Ovarian volumes were evaluated by MRI in 14 patients and compared to age matched controls, prepubertal controls and postmenopausal controls. The ovarian volumes of the galactosemic girls were smaller than those of the age matched controls (p = 0.001) and the prepubertal ovaries (p = 0.008), and did not differ significantly from postmenopausal ovarian volumes (p = 0.161). In conclusion we found no evidence that FSH inactivity plays a role in primary ovarian insufficiency in classic galactosemia. Moreover, ovarian imaging results point to an early onset of ovarian failure in this disease.
Uncrossing the U.S. Black-White Mortality Crossover: The Role of Cohort Forces in Life Course Mortality Risk
Authors: Masters Ryan K. 
Published: June 2012

AbstractIn this article, I examine the black-white crossover in U.S. adult all-cause mortality, emphasizing how cohort effects condition age-specific estimates of mortality risk. I employ hierarchical age-period-cohort methods on the National Health Interview Survey-Linked Mortality Files between 1986 and 2006 to show that the black-white mortality crossover can be uncrossed by factoring out period and cohort effects of mortality risk. That is, when controlling for variations in cohort and period patterns of U.S. adult mortality, the estimated age effects of non-Hispanic black and non-Hispanic white U.S. adult mortality risk do not cross at any age. This is the case for both men and women. Further, results show that nearly all the recent temporal change in U.S. adult mortality risk was cohort driven. The findings support the contention that the non-Hispanic black and non-Hispanic white U.S. adult populations experienced disparate cohort patterns of mortality risk and that these different experiences are driving the convergence and crossover of mortality risk at older ages.
World Health Organization Guidelines: Use of cryotherapy for cervical intraepithelial neoplasia
Authors: Santesso Nancy , Schünemann Holger , Blumenthal Paul , De Vuyst Hugo , Gage Julia , Garcia Francisco , Jeronimo Jose , Lu Ricky , Luciani Silvana , Quek Swee C. , Awad Tahany , Broutet Nathalie 
Published: June 2012

AbstractBackgroundIn 2008, cervical cancer was responsible for 275 000 deaths, of which approximately 88% occurred in low‐ and middle‐income countries. In 2009, the World Health Organization (WHO) committed to updating recommendations for use of cryotherapy for cervical intraepithelial neoplasia (CIN).Methods and resultsWe followed the WHO Handbook for Guidelines Development to develop present guidelines. An expert panel was established, which included clinicians, researchers, program directors, and methodologists. An independent group conducted systematic reviews and produced evidence summaries following the GRADE approach. GRADE evidence profiles were created for 16 key questions about the effects of cryotherapy in the presence of histologically confirmed CIN compared with no treatment and with loop electrosurgical excision procedure, as well as the use of different cryotherapy techniques. We identified a small number of randomized controlled trials or independently controlled observational studies. Surrogate outcomes were reported when evidence about outcomes critical to decision making were not available. The panel made 14 recommendations and documented factors that determined the strength and direction of the recommendations in decision tables.ConclusionThe present document summarizes new evidence‐based WHO recommendations about the use of cryotherapy in women with histologically confirmed CIN for low‐, middle‐, and high‐income countries.
Influence of porous media heterogeneity on nonaqueous phase liquid dissolution fingering and upscaled mass transfer
Authors: Farthing M. W. , Seyedabbasi M. A. , Imhoff P. T. , Miller C. T. 
Published: June 2012

The utility of existing models for describing upscaled mass transfer from nonaqueous phase liquid (NAPL) were examined when preferential dissolution pathways form in NAPL‐contaminated zones that extend over the scale of decimeters. Laboratory experiments were conducted in two well‐characterized, heterogeneous packings. Using data from these experiments and simulations, existing methods for upscaling the mass transfer rate coefficient for NAPL dissolution based on dissolution front length growth (LDF), aquifer heterogeneity and spatial moments of NAPL distribution, and the ganglia‐to‐pool ratio (GTP) were evaluated along with an equilibrium stream tube (EST) model for predicting contaminant flux. When the correlation length of permeability perpendicular to the mean water flow direction was 6.0 cm, greater than the scale of dissolution fingers, only 4.8% of the NAPL resided in pools. Dissolution fingers formed in this experiment, and the LDF, GTP, and EST models resulted in similar predictions of effluent concentrations, with root‐mean‐square errors (RMSEs) between 0.035 and 0.079 and the LDF‐heterogeneous model best. When the correlation scale was smaller (1.0 cm), 66.7% of the NAPL was in pools, and preferential dissolution pathways were dominated by channeling, preferential dissolution caused by spatial variations in aqueous phase permeability, and NAPL saturation. For this experiment the EST and GTP models performed well, with RMSEs of 0.055 and 0.103, respectively. Dissolution fingering was important when the permeability correlation length was sufficiently large that dissolution finger formation was not disrupted and NAPL pools were not dominant.