bluuebunny/crossref_metadata_2025 huggingface dataset:
OPENING THE BLACK BOX OF TECHNOLOGY ADOPTION: THE MOTIVE-TECHNOLOGY-BELIEF FRAMEWORK
Authors: ZENOBIA BRENT A. , WEBER CHARLES M.
Published: January 2012

A qualitative empirical study explores the psychological process by which transportation consumers adopt alternatives to single occupancy vehicles. The study's findings give rise to the Motive-Technology-Belief (MTB) framework, a theory that conceives of technology adoption in terms of three mental structures: motives are inner mental reasons; technologies are tools that pertain to motives; and beliefs are associations between motives and/or technologies. Their behavioral interactions are governed by three conscious processes: selecting is the process of choosing a tool in response to an immediate need; evaluating is the process of forming beliefs about tools; and maintaining is the process of determining the functional status of tools. They are augmented by five unconscious auxiliary processes: perceiving, focusing, framing, consolidating, and acting.

The primary contribution of this paper is the first coherent theory that explains some of the inner mental processes pertaining to technology adoption. However, the study described in this paper also combines existing theory with original field research to lay the foundation for a more comprehensive causal theory of the adoption process that will provide a step-by-step explanation of how events or life experiences cause a consumer's beliefs about a technology to change over time. Finally, the study identifies evaluating, selecting, maintaining, and the auxiliary processes that govern motivation as fundamental "microlaws" of innovation i.e. regular rules describing the generating processes of emergent innovations.
Signal transduction in a compliant thick ascending limb
Authors: Layton Anita T. , Moore Leon C. , Layton Harold E.
Published: January 2012

In several previous studies, we used a mathematical model of the thick ascending limb (TAL) to investigate nonlinearities in the tubuloglomerular feedback (TGF) loop. That model, which represents the TAL as a rigid tube, predicts that TGF signal transduction by the TAL is a generator of nonlinearities: if a sinusoidal oscillation is added to constant intratubular fluid flow, the time interval required for an element of tubular fluid to traverse the TAL, as a function of time, is oscillatory and periodic but not sinusoidal. As a consequence, NaCl concentration in tubular fluid alongside the macula densa will be nonsinusoidal and thus contain harmonics of the original sinusoidal frequency. We hypothesized that the complexity found in power spectra based on in vivo time series of key TGF variables arises in part from those harmonics and that nonlinearities in TGF-mediated oscillations may result in increased NaCl delivery to the distal nephron. To investigate the possibility that a more realistic model of the TAL would damp the harmonics, we have conducted new studies in a model TAL that has compliant walls and thus a tubular radius that depends on transmural pressure. These studies predict that compliant TAL walls do not damp, but instead intensify, the harmonics. In addition, our results predict that mean TAL flow strongly influences the shape of the NaCl concentration waveform at the macula densa. This is a consequence of the inverse relationship between flow speed and transit time, which produces asymmetry between up- and downslopes of the oscillation, and the nonlinearity of TAL NaCl absorption at low flow rates, which broadens the trough of the oscillation relative to the peak. The dependence of waveform shape on mean TAL flow may be the source of the variable degree of distortion, relative to a sine wave, seen in experimental recordings of TGF-mediated oscillations.
What can fMRI tell us about functional variability in the oculomotor system and saccade performance?
Authors: Chan Jason L. , Kucyi Aaron
Published: January 2012

Eye movement behavior is variable, and the brain's oculomotor circuitry may not always function consistently. In a recent fMRI study, Ozyurt and Greenlee (2011) correlated the activation strength of cortical and striatal brain regions with inter- and intraindividual variability in saccade performance. We discuss the design and implications of this study with regard to the differences between inter- and intraindividual variability, and the link between the BOLD signal and oculomotor activity.
A ComparativeIn VitroStudy of the Effects of Separate and Combined Products ofCitrus e fructibusandCydonia e fructibuson Immunological Parameters of Seasonal Allergic Rhinitis
Authors: Baars E. W. , Jong M. C. , Boers I. , Nierop A. F. M. , Savelkoul H. F. J.
Published: January 2012

This paper examined the effects of the combined product,Citrus e fructibus/Cydonia e fructibus(Citrus/Cydonia; Citrus and Cydonia: each 0.01 g/mL), and separate products of Citrus (0.01 g/mL) and Cydonia (0.01 g/mL) on the immunological pathways involved in seasonal allergic rhinitis (SAR). Peripheral blood mononuclear cells (PBMCs) from five healthy and five grass pollen-allergic donors were isolated and analyzedin vitroafter polyclonal and allergen-specific stimulation of T cells in the presence of the three extracts. The analyses demonstrated acceptable cell survival with no signs of toxicity. Citrus mainly had a selective effect on reducing allergen-specific chronic inflammatory (TNF-α; Citrus compared to Cydonia and Citrus/Cydonia: −87.4 (P<0.001) and −68.0 (P<0.05), resp.) and Th2 pathway activity (IL-5; Citrus compared to Cydonia: −217.8 (P<0.01); while, both Cydonia and Citrus/Cydonia mainly affected the induction of the allergen-specific Th1 pathway (IFN-γ; Cydonia and Citrus/Cydonia compared to Citrus: 3.8 (P<0.01) and 3.0 (P<0.01), resp.). Citrus and Cydonia demonstrated different working mechanisms in the treatment of SAR and the combination product did not demonstrate larger effects than the separate preparations. Further effectiveness and efficacy studies comparing the effects of the products on SARin vivoare indicated.
Abdominal Tumor Characterization and Recognition Using Superior-Order Cooccurrence Matrices, Based on Ultrasound Images
Authors: Mitrea Delia , Mitrea Paulina , Nedevschi Sergiu , Badea Radu , Lupsor Monica , Socaciu Mihai , Golea Adela , Hagiu Claudia , Ciobanu Lidia
Published: January 2012

The noninvasive diagnosis of the malignant tumors is an important issue in research nowadays. Our purpose is to elaborate computerized, texture-based methods for performing computer-aided characterization and automatic diagnosis of these tumors, using only the information from ultrasound images. In this paper, we considered some of the most frequent abdominal malignant tumors: the hepatocellular carcinoma and the colonic tumors. We compared these structures with the benign tumors and with other visually similar diseases. Besides the textural features that proved in our previous research to be useful in the characterization and recognition of the malignant tumors, we improved our method by using the grey level cooccurrence matrix and the edge orientation cooccurrence matrix of superior order. As resulted from our experiments, the new textural features increased the malignant tumor classification performance, also revealing visual and physical properties of these structures that emphasized the complex, chaotic structure of the corresponding tissue.
Synthesis and Characterization of Se35Te65−xGex Nanoparticle Films and Their Optical Properties
Authors: Salah Numan , Habib Sami S. , Khan Zishan H. , Alarfaj Esam , Khan Shamshad A.
Published: January 2012

Thin films of Se35Te65−xGex (x = 0, 3, 6, 9, 12) nanoparticles were synthesized using thermal evaporation method. They were characterized by X‐ray diffraction (XRD), scanning electron microscope (SEM), and absorption and transmission spectra. XRD results show that these films are of amorphous nature, while SEM images show nanoparticles with average particle size around 30 nm. No significant changes are observed in morphology of the deposited films by changing concentrations of Te and Ge. The optical behaviors of these films have been studied using the absorption and transmission spectra in the spectral region 400–1100 nm. The absorption, extinction coefficients and refractive index were obtained and investigated in more detail. The optical band gap (Eg) values were also determined and are found to decrease from 0.83 to 0.69 eV by increasing the concentration of Ge from 0 to 12. The transmission spectra for the thin films of Se35Te65−xGex nanoparticles show strong absorption at wavelength less than 500 nm and become highly transparent at wavelength above 800 nm. No significant changes in the transmission spectra are observed by increasing concentration of Ge. These results might be useful for development of optical disks and other semiconducting devices based on these nanochalcogenides.
3D Rigid Registration of Intraoperative Ultrasound and Preoperative MR Brain Images Based on Hyperechogenic Structures
Authors: Coupé Pierrick , Hellier Pierre , Morandi Xavier , Barillot Christian
Published: January 2012

The registration of intraoperative ultrasound (US) images with preoperative magnetic resonance (MR) images is a challenging problem due to the difference of information contained in each image modality. To overcome this difficulty, we introduce a new probabilistic function based on the matching of cerebral hyperechogenic structures. In brain imaging, these structures are the liquid interfaces such as the cerebral falx and the sulci, and the lesions when the corresponding tissue is hyperechogenic. The registration procedure is achieved by maximizing the joint probability for a voxel to be included in hyperechogenic structures in both modalities. Experiments were carried out on real datasets acquired during neurosurgical procedures. The proposed validation framework is based on (i) visual assessment, (ii) manual expert estimations , and (iii) a robustness study. Results show that the proposed method (i) is visually efficient, (ii) produces no statistically different registration accuracy compared to manual-based expert registration, and (iii) converges robustly. Finally, the computation time required by our method is compatible with intraoperative use.
Multi-Objective Genetic Algorithm for Task Assignment on Heterogeneous Nodes
Authors: del Notario Carolina Blanch Perez , Baert Rogier , D'Hondt Maja
Published: January 2012

Task assignment in grid computing, where both processing and bandwidth constraints at multiple heterogeneous devices need to be considered, is a challenging problem. Moreover, targeting the optimization of multiple objectives makes it even more challenging. This paper presents a task assignment strategy based on genetic algorithms in which multiple and conflicting objectives are simultaneously optimized. Specifically, we maximize task execution quality while minimizing energy and bandwidth consumption. Moreover, in our video processing scenario; we consider transcoding to lower spatial/temporal resolutions to tradeoff between video quality; processing, and bandwidth demands. The task execution quality is then determined by the number of successfully processed streams and the spatial-temporal resolution at which they are processed. The results show that the proposed algorithm offers a range of Pareto optimal solutions that outperforms all other reference strategies.
Diversity Gain through Antenna Blocking
Authors: Dehghanian V. , Nielsen J. , Lachapelle G.
Published: January 2012

As part of the typical usage mode, interaction between a handheld receiver antenna and the operator's RF absorbing body and nearby objects is known to generate variability in antenna radiation characteristics through blocking and pattern changes. It is counterintuitive that random variations in blocking can result in diversity gain of practical applicability. This diversity gain is quantified from a theoretical and experimental perspective. Measurements carried out at 1947.5 MHz verify the theoretical predictions, and a diversity gain of 3.1 dB was measured through antenna blocking and based on the utilized measurement setup. The diversity gain can be exploited to enhance signal detectability of handheld receivers based on a single antenna in indoor multipath environments.
E. coli-Produced BMP-2 as a Chemopreventive Strategy for Colon Cancer: A Proof-of-Concept Study
Authors: Yuvaraj Saravanan , Al-Lahham Sa’ad H. , Somasundaram Rajesh , Figaroa Patrick A. , Peppelenbosch Maikel P. , Bos Nicolaas A.
Published: January 2012

Colon cancer is a serious health problem, and novel preventive and therapeutical avenues are urgently called for. Delivery of proteins with anticancer activity through genetically modified bacteria provides an interesting, potentially specific, economic and effective approach here. Interestingly, bone morphogenetic protein 2 (BMP-2) is an important and powerful tumour suppressor in the colon and is thus an attractive candidate protein for delivery through genetically modified bacteria. It has not been shown, however, that BMP production in the bacterial context is effective on colon cancer cells. Here we demonstrate that transformingE. coliwith a cDNA encoding an ileal-derived mature human BMP-2 induces effective apoptosis in anin vitromodel system for colorectal cancer, whereas the maternal organism was not effective in this respect. Furthermore, these effects were sensitive to cotreatment with the BMP inhibitor Noggin. We propose that prevention and treatment of colorectal cancer using transgenic bacteria is feasible.
Brain Imaging in Patients with Transient Ischemic Attack: A Comparison of Computed Tomography and Magnetic Resonance Imaging
Authors: Förster A. , Gass A. , Kern R. , Ay H. , Chatzikonstantinou A. , Hennerici M.G. , Szabo K.
Published: January 2012

Background: Brain imaging in stroke aims at the detection of the relevant ischemic tissue pathology. Cranial computed tomography (CT) is frequently used in patients with transient ischemic attack (TIA) but no data is available on how it directly compares to magnetic resonance imaging (MRI). Methods: We compared detection of acute ischemic lesions on CT and MRI in 215 consecutive TIA patients who underwent brain imaging with either CT (n = 161) or MRI (n = 54). An MRI was performed within 24 h in all patients who had CT initially. Results: An initial assessment with CT revealed no acute pathology in 154 (95.7%) and possible acute infarction in 7 (4.3%) patients. The acute infarct on CT was confirmed by diffusion-weighted imaging (DWI) in only 2 cases (28.6%). DWI detected an acute infarct in 50 of the 154 patients with normal baseline CT (32.5%). Among 54 patients without baseline CT, DWI showed acute ischemic lesions in 19 (35.2%). The ischemic lesions had a median volume of 0.87 cm3 (range: 0.08–15.61), and the lesion pattern provided clues to the underlying etiology in 13.7%. Conclusion: Acute MRI is advantageous over CT to confirm the probable ischemic nature and to identify the etiology in TIA patients.
Effect of Serum Lipid Levels on Stroke Outcome after rt-PA Therapy: SAMURAI rt-PA Registry
Authors: Makihara Noriko , Okada Yasushi , Koga Masatoshi , Shiokawa Yoshiaki , Nakagawara Jyoji , Furui Eisuke , Kimura Kazumi , Yamagami Hiroshi , Hasegawa Yasuhiro , Kario Kazuomi , Okuda Satoshi , Naganuma Masaki , Toyoda Kazunori
Published: January 2012

Background: The effects of lipid levels on clinical outcomes after ischemic stroke are controversial. Whether admission lipid levels and prior statin use are associated with early intracerebral hemorrhage (ICH) and long-term functional outcome after recombinant tissue plasminogen activator (rt-PA) therapy for stroke patients was investigated. Methods: Ischemic stroke patients who received intravenous rt-PA from a multicenter registry were studied. Lipid levels on admission, including total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and triglyceride levels, as well as prior statin use, were assessed. The primary outcome was favorable outcome at 3 months corresponding to a modified Rankin Scale score ≤1. The secondary outcome was any or symptomatic ICH within the initial 36 h. Results: Of 489 enrolled patients (171 women, 70.8 ± 11.6 years old), 60 used statins prior to stroke, 93 developed ICH (19.0%), and 188 (38.4%) had a favorable 3-month outcome. Of the lipid levels, only the HDL-C level was an independent predictor of favorable outcome after multivariate adjustment for baseline characteristics (OR 1.95, 95% CI 1.10–3.47 per 1 mmol/l; p = 0.023) and after further adjustment for pretreatment radiological findings (OR 2.03, 95% CI 1.07–3.84; p = 0.029). For the 187 stroke patients without cardioembolism, the HDL-C level was more strongly associated with favorable outcome (OR 4.94, 95% CI 1.91–12.76 per 1 mmol/l; p = 0.001). There were no significant associations between ICH and any lipid levels. Prior statin use was not associated with outcomes. Conclusions: The admission HDL-C level was associated with favorable outcome 3 months after intravenous rt-PA therapy in stroke patients without cardioembolism.
Strategies Beyond Genome-Wide Association Studies for Atherosclerosis
Authors: Maouche Seraya , Schunkert Heribert
Published: January 2012

Atherosclerotic diseases, including coronary artery disease (CAD) and myocardial infarction (MI), are the leading causes of death in the world. The genetic basis of CAD and MI, which are caused by multiple interacting endogenous and exogenous factors, has gained considerable interest in the last years as genome-wide association studies (GWASs) have identified many new susceptibility loci for CAD and MI, and the underlying genes provide new insights into the genetic architecture of these diseases. Here we summarize the recent findings from GWASs of atherosclerosis and discuss their functional and biological implications. We also discuss the different post-GWAS strategies that are currently used for refining the location of causal variants, understanding their role, and shedding light on molecular mechanisms explaining their association to CAD. We finally discuss potential clinical translations of GWAS findings for individual risk prediction, advanced clinical strategies, and personalized treatments.
Bakunin: A View from Within
Authors: MENDEL ARTHUR
Published: January 2012

I never felt myself particularly suited for life in society. I felt stupid, awkward, inarticulate. I used to think that this was merely because of my inexperience. I did everything in my power to overcome it. I immersed myself in society; I scurried this way and that; and what did I find? A terrible emptiness. The pleasures and distractions that delighted others seemed to me trivial. Dances, balls-these, the pinnacle of pleasure for our youth, the highest ideals they can imagine, bored me to death. As soon as they began, I felt out of place and just as trivial as they were. I had to reject all this, and I did so, joyfully, enthusiastically, vowing never to return.... But, then, I had to find something else: the vacuum that overwhelmed me had to be filled. I withdrew into myself and locked myself in. I studied myself; and, in the end, I found within myself something to fill the emptiness.... At last I made a decision, and as soon as I did a warmth so sweet poured through my heart. I threw myself into my study; I threw myself passionately into it.... I feel as though I am being reborn; I feel as though I am watching myself being fed and nurtured. Until now I have lived only an external life. I want now to build for myself an inner existence.1
A New Visible Albedo Normalization Method: Quasi-Lambertian Surface Adjustment
Authors: Zhuge Xiao-yong , Yu Fan , Wang Ye
Published: January 2012

A new visible (VIS; 0.55–0.9 μm) albedo normalization method, that is, the quasi-Lambertian surface adjustment (QLSA), is developed herein by using the geostationary meteorological satellite data and radiative transfer model. Taking the variation of relative locations between the sun, satellite, and clouds into account, the QLSA effectively reduces the inconsistencies in the VIS image brightness caused by the Lambertian surface approximation to cloud tops (i.e., the reflection characteristic is isotropic). The evaluation, using Chinese and Japanese geostationary satellite data, shows that the QLSA is more effective and accurate than three other albedo normalization methods currently in use. The new algorithm is applicable in regions with solar zenith angle and satellite zenith angle less than 60°, which, in the summertime, approximately corresponds to the time range from 0800 to 1600 local time (LT).
Preparation of copper–graphite composite particles by milling process
Authors: Motozuka S , Tagaya M , Ikoma T , Yoshioka T , Xu Z , Tanaka J
Published: January 2012

The fabrication of copper–graphite composites by a milling process was investigated using a centrifugal ball mill. The copper particles were homogeneously milled in a graphite vessel, and the reaction time was varied. Scanning electron microscopy images clearly revealed that a fragment of graphite ground by the copper particle adheres to the copper particle surface, indicating the formation of a copper–graphite composite. The composite graphite amount per 1 g of copper particles increased to 0.46 mg at the milling time 5 min, and subsequently decreased to 0.25 mg at 60 min, indicating the suitable milling-time for the interfacial adhesion. When using only the copper particles, the naturally oxidized layer on the surface decreased with milling. On the other hand, when using only the graphite, the characteristic graphite structure is disrupted and the defect structure increased with milling. Thus, the new copper surface generated by milling strongly reacts with the defect structure of the graphite. It is suggested that the interfacial bonding between the copper and graphite was attributed to a Van der Waals attraction and/or binding force due to oxygen atoms located at the interface.
Preparation and electrical characterization of Au/n-Si (1 1 0) structure with PVA–nickel acetate composite film interfacial layer
Authors: Tunç T , Gökçen M
Published: January 2012

Two types of Schottky diodes, with and without PVA (Ni-doped) layer, were fabricated to investigate whether or not the PVA (Ni-doped) layer is effective on some electrical parameters such as ideality factor n, barrier height [Formula: see text] , series resistance Rs, and interface state density NSS. PVA (Ni-doped) microdrops film was deposited on n-type silicon substrate. SDs with and without PVA (Ni-doped) layer, namely MPS and MS diodes, respectively, were investigated by current–voltage ( I–V) measurements at room temperature. Also, series resistance calculations have been performed using Cheung method. The values of n and Rs obtained for MPS are found higher compared to those of MS. This is attributed to the particular distribution of NSS, and inhomogeneity of barrier height and interfacial layer at metal/semiconductor (M/S) interface. Au/PVA(Ni-doped)/n-Si diode (MPS) exhibits a photovoltaic behavior with an open circuit voltage Voc 0.42 V and short-circuit current ISC 33.2 µA under 100 mW/cm2 illumination intensity. The obtained photovoltaic results indicate that the MPS diode can be used as an efficient material for applications in optoelectronic applications such as solar cells and photodiode devices.
Perspectives in the Effective Use of Fluoride in Asia
Authors: Petersen P.E. , Phantumvanit P.
Published: January 2012

Dental caries is the most prevalent chronic disease affecting human populations worldwide. The diverse disease patterns across and within countries are related to socio-behavioral determinants, demographic factors, environmental conditions, and the availability and accessibility of oral health services, in particular, exposure to disease prevention programs (Petersen, 2003, 2008a). Benefits of fluoride for caries prevention have been substantiated in many countries (Petersen and Lennon, 2004; Jones et al., 2005). In the second half of the 20th century, this focus shifted to the development and evaluation of fluoride toothpastes and rinses and, to a lesser extent, to alternatives to water fluoridation, such as salt and milk fluoridation. Most recently, efforts have been made to summarize this extensive database through systematic reviews of fluoride administration (McDonagh et al., 2000; Marinho et al., 2003; Australian Government, 2007). The Asian workshop held in Phan-Nga, Thailand, during March 22-24, 2011, aimed to discuss current information on fluoride and dental caries, as well as to try identifying barriers and opportunities that countries of Asia may have for implementing such programs. In addition, the intention was to give recommendations for including fluoride schemes within national public health programs.
Respiratory biofeedback accuracy in chronic renal failure patients: a method comparison
Authors: Figueiredo Rogério Ramos , Castro Antonio AM , Napoleone Fernanda MG Gonzaga , Faray Leina , de Paula Júnior Alderico Rodrigues , Osório Rodrigo Alexis Lazo
Published: January 2012

Objective:

To analyse respiratory biofeedback effects on respiratory muscle strengthening in chronic renal failure patients.

Design:

Randomized controlled study.

Setting:

Nephrology and dialysis centre.

Subjects and intervention:

Forty-one end-stage renal patients on haemodialysis treatment were allocated into three groups: control ( n = 10), G-1 (inspiratory muscle training using Threshold IMT device; n = 16) and G-2 (biofeedback; n = 15) and given respiratory muscle training (three sessions/week for six weeks).

Main measures:

Forced vital capacity (FVC), expiratory volume in the first second (FEV1), FEV1/FVC ratio, maximal voluntary ventilation (MVV) and maximal inspiratory (MIP) and expiratory (MEP) pressures were measured before and after the respiratory muscle training programme.

Results:

Both training methods were efficient since we found an increase after training in the FVC in the G-1 group (from 2.45 ± 0.17 to 2.85 ± 0.16; P = 0.001) and in the G-2 group (from 2.35 ± 0.19 to 2.55 ± 0.19; P = 0.007), in the FEV1 in G-1 (from 2.18 ± 0.16 to 2.46 ± 0.14; P = 0.01) and in G-2 (from 1.97 ± 0.17 to 2.20 ± 0.15; P < 0.0001), MIP in G-1 (from 70.63 ± 4.03 to 108.75 ± 7.41; P < 0.0001) and in G-2 (from 67.67 ± 5.02 to 96.33 ± 8.30; P < 0.001) and MEP in G-1 (from 73.13 ± 5.10 to 82.50 ± 6.74; P = 0.007) and in G-2 (from 67.67 ± 5.41 to 76.00 ± 4.29; P = 0.002).

Conclusions:

Respiratory biofeedback is efficient as a respiratory muscle training modality for patients with chronic renal failure.
A poly(glycerol-sebacate-(5-fluorouracil-1-acetic acid)) polymer with potential use for cancer therapy
Authors: Sun Zhi-Jie , Sun Bo , Sun Cheng-Wu , Wang Li-Bo , Xie Xin , Ma Wen-Chao , Lu Xi-Li , Dong De-Li
Published: January 2012

In this study, 5-fluorouracil-1-acetic acid was chemically conjugated with poly(glycerol-sebacate) (PGS) to form a unitary polymer poly(glycerol-sebacate- (5-fluorouracil-1-acetic acid)) (PGS-5-FU-CH2COOH). The structure, the in vitro antitumor activity of 5-FU-CH2COOH, the in vitro degradation, the drug release, and antitumor activity as well as the in vivo degradation and tissue biocompatibility of PGS-5-FU-CH2COOH were investigated. The 5-FU-CH2COOH inhibited HeLa (human cervical cancer cell line) and SGC-7901 (human gastric adenocarcinoma cell line) tumor cells with a half maximal inhibitory concentration (IC50) of 0.196 and 0.267 μM, respectively, after a 3-day incubation. The in vitro drug release profiles of PGS-5-FU-CH2COOH exhibited a biphasic release with an initial exponential phase in the first week and then the second constant linear phase. An in vitro antitumor assay of the PGS-5-FU-CH2COOH polymer showed significant cytotoxicity against tumor cells. The implanted PGS-5-FU-CH2COOH degraded completely in 1 month after implantation. The antitumor activity and improved drug release profile of PGS-5-FU-CH2COOH indicate its potential as an implantable polymer for cancer therapy.
Adolescent Sexual Risk and Multiple Contexts
Authors: Rodgers Kathleen Boyce , McGuire Jenifer K.
Published: January 2012

In this study we estimated the combined effects of violence experiences, parenting processes, and community poverty on sexual onset, alcohol or other drug (AOD) use at last sex, multiple sex partners, and prior pregnancy in a sample of 7th-, 9th-, and 11th-grade adolescents ( n = 7,891), and the subsample of sexually experienced adolescents ( n = 2,108). Multilevel multivariate logistic regression analyses revealed that having experienced any interpersonal violence, and low levels of perceived parental warmth and parental knowledge predicted sexual onset. Adult sexual abuse or peer sexual coercion increased the odds for AOD use at last sex and having multiple sexual partners. When demographic, violence experiences and parenting behaviors were accounted for, poverty was not associated with sexual onset, AOD use at last sex, or multiple sex partners. Results suggest prevention efforts to reduce teen dating violence may be especially important to diminish sexually risky behaviors among adolescents.
Associations Between Expectancies of Alcohol and Drug Use, Severity of Partner Violence, and Posttraumatic Stress Among Women
Authors: Peters Erica N. , Khondkaryan Enna , Sullivan Tami P.
Published: January 2012

Women who experience recurrent intimate partner violence (IPV) may use alcohol or drugs because they expect that these substances will help them cope with the negative physical and psychological sequelae of IPV. However, expectancies for alcohol and drug use have not been explored among this population of women. We used the Relaxation and Tension-Reduction Scale, Arousal and Aggression Scale, and Social Assertion Scale of the Alcohol Expectancy Questionnaire and modified its items to assess both alcohol and drug expectancies of 212 community-based, IPV-exposed women. Results of bivariate correlations showed that greater alcohol and drug expectancies were significantly correlated with greater alcohol problems and greater posttraumatic stress total and symptom severity scores. Results of a multivariate regression model showed that after controlling for demographic characteristics and history of childhood trauma, Relaxation and Tension- Reduction expectancies were associated with number of days of alcohol use, alcohol problems, physical and sexual IPV severity scores, and posttraumatic stress total and reexperiencing symptom severity scores. Expectancies do not significantly moderate the relationships between IPV, posttraumatic stress, and problematic alcohol and drug use. Given the strong relationships of expectancies with IPV severity, posttraumatic stress, and alcohol problems, expectancies may serve as targets for interventions to reduce alcohol use and problems and improve health-related outcomes in IPV-exposed women.
Discrete time touristic volume analysis in mean–variance spaces: the French hospitality sector situation
Authors: Goncalves Olga , Ratsimbanierana Hermann
Published: January 2012

This article presents an empirical study of Luenberger indicator in a portfolio selection context ( Brandouy et al., 2010 ) that we use in Tourism. Over time, we gauge market segment efficiency of overnight stays growth by the shortage function in a mean–variance space. Luenberger productivity indicator is deduced and decomposed to efficiency and volume touristic changes. The first component reveals the portfolio strategy performance, and touristic volume change appraises global market growth. The empirical results based on a sample of French overnight stays volumes during 1998–2008 period show that there is a market decrease in 2008. However, we note that for some market segments a lower volume does not necessarily mean lower productivity. The France destination strategy drive until 2008, permits us to have a better and more stable growth than the previous period.
Utilizing Graphical Formats to Convey Uncertainty in a Decision Making Task
Authors: Finger Richard , Bisantz Ann M.
Published: January 2012

Understanding how to effectively display uncertain information has become increasingly important as decision aids are able to provide operators with situational estimates and their associated uncertainty. This paper describes an experiment in which degraded icons were used to convey uncertainty. Results indicated similar performance using degraded images or numeric probabilities, suggesting that the use of degraded images may be a viable method for displaying uncertainty.
Staff Actions and Alarms in a Neonatal Intensive Care Unit
Authors: Bitan Yuval , Meyer Joachim , Shinar David , Zmora Ehud
Published: January 2012

Operators of complex systems must perform routine actions while attending to and responding to unexpected events. The current study extends previous laboratory experiments on the performance of such complex tasks to the analysis of the medical staffs actions in a Neonatal Intensive Care Unit (NICU). Observations showed that the attendants usually do not respond directly to warnings given from monitors, but that the sequence and timing of actions is affected by the warnings. The staff initiated most actions. There was no evidence for discrete decision points, but rather a continuous flow of activities. However, the overall pattern of actions corresponds to the predictions from analytical scheduling methods. These results and other observations of the staffs actions were analyzed in terms of “naturalistic decision making” and analytic decision analysis.
The Role of Context and Progressive Commitment in Plan Continuation Error
Authors: McCoy C. Elaine , Mickunas Algis
Published: January 2012

Plan continuation error is grounded in progressive commitment. This brief discussion utilizes an alternative, complementary methodology to explore the relationship of context to plan fixation in plan continuation error. This study augments a more comprehensive, data-based research effort that seeks to identify how context contributes to General Aviation pilot errors in weather-related decision-making. Context should be broadly considered as a complex configuration of relevant events or phenomenon that may be considered the domain within which the pilot makes the weather-related decision.
The Effect of Different Styles of Human-Machine Interaction on the Nature of Operator Mental Models
Authors: Moray Neville , Butler Colleen
Published: January 2012

The well-known Sheridan and Verplank scale of human-machine interaction suggests that there will be considerable differences in the kind of mental model operators will acquire of systems which they control. This paper reports the use of observing responses and Markov modelling to try to identify such differences in mental models. The method detects differences in the way in which operators allocate attention to aspects of the system as a function of the Sheridan-Verplank level of interaction. Such differences are believed to reflect differences in the causal properties embodied in the mental models.
Analyzing Shared Mental Models
Authors: Langan-Fox Janice , Wirth Anthony , Code Sharon , Langfield-Smith Kim , Wirth Andrew
Published: January 2012

In recent years, there has been a resurgence of interest in the notion of shared cognition and team mental models (Klimoski & Mohammed, 1994). While a number of techniques have been developed to measure mental model similarity dyadically, team mental model measurement has eluded researchers. This presents a problem for the evolution of the team mental model concept in psychology and the establishment of its validity, for example, as a predictor of team performance. The primary aim of this paper is to describe the application of randomization tests as a new method for measuring mental model similarity at the team-level, that is the measurement of team mental models.
Situation Models: An Avenue to the Modeling of Mental Models
Authors: Endsley Mica R.
Published: January 2012

The concept of a mental model is well ensconced in the human factors literature. Mental models are used to explain a wide variety of human behavior and designers are directed to design to fit the mental model of the user. Its real utility in practical application remains beyond our grasp, however, due to significant difficulties in creating usable representations of these mental models that can provide descriptive arid predictive capabilities. This paper explores the concept of mental models and a highly related concept, the situation model. Through the situation model, a method for abstracting user knowledge and creating usable models of their mental model is explored. This technique shows promise as a means of more effectively capturing this elusive construct.
Team Decision-Making Strategies: Implications for Designing the Interface in Complex Tasks
Authors: Miller Sheryl L. , Adelman Leonard , de Henderson E. Vere , Schoelles Michael , Yeo Cedric
Published: January 2012

Two longitudinal experiments were designed to challenge teams performing a time-critical aircraft identification task (Team Argus). In the first experiment, it was predicted that teams would use different strategies to maintain performance across increasing levels of time pressure. However, at some point these strategies would become inadequate, and performance would not be recoverable. The identification of these critical temporal stress levels and strategies suggested interface design modifications that would help teams maintain performance longer. The findings obtained were then used to inform improved interface designs, that would mediate the effects of time pressure. The successfulness of these interface changes were evaluated in the second experiment, comparing team performance on the same task using perceptually-aided and cognitively-aided interfaces and the original un-aided interface.
Distance: A Metric for Flight Deck Design and Function Allocation
Authors: Schutte Paul C.
Published: January 2012

Designing the appropriate level of automation has always been difficult. Too much automation and the human operator may become cognitively disjoint from the task at hand. Too little automation and the operator may be overwhelmed by the task of translating higher level goals into lower level commands. This paper builds on research in the topic areas of human-centered design, levels of automation, and function allocation to provide a lexicon of metaphors and metrics to be used for setting context dependent interface points. This lexicon is explicated using examples from commercial aviation.
Effect of Intelligent Instruction on Students' Mental Models and Performance
Authors: Kahler Susan E. , Converse Sharolyn A. , Lester James , Cheatham Deane , Stelling Gary
Published: January 2012

The effects of two types of Intelligent Computer Aided Instruction (ICAI) and a non-intelligent tutoring system on the development of students' mental models and on performance was explored. One of the two ICAI systems provided both principle-based and task specific advice while the other provided task specific advice only. The non-intelligent CAI provided no advice. The problems presented to students increased in difficulty as the student progressed. It was hypothesized that the mental models of students who interacted with the ICAI that provided both principle-based and task specific advice would be most similar in structure to a “gold standard” model, and that these students would also exhibit the best performance. It was also hypothesized that students who were exposed to the ICAI that provided only task specific advice would perform better, and exhibit more accurate and detailed mental models than would students who interacted with the CAI that provided no advice. Study results indicated that students in both ICAI conditions achieved a higher similarity index, fewer errors, and faster task time, than did students in the no advice group. However, there was no significant difference between the two ICAIs for any of these measures. There was a significant interaction between version and problem difficulty for task time. As problem difficulty increased, task time increased for both of the two ICAI conditions, but not for the no-advice condition. These results are discussed in terms of their implications for the predictive validity of the Pathfinder measure, and in terms of the appropriate use and design of ICAI.
Setting the Requirements for a User-Friendly Infusion Pump
Authors: Liljegren Erik , Osvalder Anna-Lisa , Dahlman Sven
Published: January 2012

The infusion pump is a commonly used piece of equipment at the Intensive Care Unit. The pumps often are from different manufacturers and have different handling characteristics. The ICU is a dynamic environment, with periods of calm interrupted by periods of very high activity and mental load. Infusion pumps are often involved in reported incidents. The purpose of this study was to set requirements for a user interface for an infusion pump, using a systematic human factors approach. The method used consisted of field studies at an ICU, a critical evaluation of two pumps presently used at this ICU and an analysis of reported incidents which involved infusion pumps. Both pumps in the evaluation had a number of latent errors. Two types of incidents relating directly to the user interface were found, both of which could be traced back to latent errors. A number of requirements were set with the purpose of reducing the risks of the two types of incidents occurring and reducing the mental load of the user. Using these requirements, a new interface for an existing volumetric pump was designed.
Managing Attention by Preparing to Forget
Authors: Altmann Erik M. , Gray Wayne D. , Gray Wayne D.
Published: January 2012

In dynamic task environments, human operators must update their memory for what is true of the current situation. This updating depends on forgetting old information, and this forgetting in turn places constraints on how an item is encoded in the first place — the cognitive system must prepare to forget. Functional decay theory accurately, predicts how long this preparation takes — concentrated use of an item for about 5 sec requires an additional 1 sec for initial encoding. This quantitative prediction illustrates the potential of functional decay theory for evaluating cognitive workload.
The Effect of Task Load and Shared Displays on Team Situation Awareness
Authors: Bolstad Cheryl A. , Endsley Mica R.
Published: January 2012

In this study, we empirically tested the effects of two types of shared displays and varying workload levels on the formation of team situation awareness (SA). Results support the use of certain types of shared displays for enhancing team performance. The way in which people use shared displays is actually quite complex and related to the workload level. The use of an abstracted shared display was found to be beneficial for enhancing team performance/while the use of shared displays that completely duplicated the other team members displays were found to be detrimental. Under low workload levels, no performance enhancements or problems were found associated with either shared display type. In high and moderate workload conditions, the significant benefits of the abstracted shared display were most apparent. Changes in team interaction style were found to accompany the use of the different types of shared displays. This study supports a model of Team SA and expands on previous research on shared displays.
Cognitive Work Analysis: Research and Applications
Authors: Vicente Kim J.
Published: January 2012

This symposium describes research motivated by cognitive work analysis, a framework for the analysis, modeling, design, and evaluation of complex sociotechnical systems. This discussant's overview describes some of the themes that cut across the four papers in the symposium.
Evaluating Design Proposals with Work Domain Analysis
Authors: Naikar Neelam , Sanderson Penelope M.
Published: January 2012

A demanding task in procuring complex military platforms is determining whether proposed designs will function effectively in the relevant work context. Conventional evaluation methods offer a limited perspective that focuses on the technical performance of designs in a small range of predictable mission scenarios. In this paper, we advocate Work Domain Analysis, a technique which describes the functions, priorities and values, and purposes of a work domain independently of particular scenarios. This framework focuses the evaluation of designs on functional properties that are relevant to a wide variety of situations, including unanticipated contingencies. Work Domain Analysis also offers a useful framework for examining human-system integration solutions. We illustrate how these concepts were used by the Australian Defence Force for the procurement of an Airborne Early Warning and Control system.
Temporal Coordination Control Task Analysis for Analysing Human-System Integration
Authors: Sanderson Penelope M. , Naikar Neelam
Published: January 2012

Evaluating whether prospective air defense systems will effectively integrate the activities of humans and computers is a pressing issue for developers and purchasers of such systems. We need effective ways of modeling human-system integration while such systems are under development and while the possibilities for action are underspecified. We present a Cognitive Work Analysis-based analytic framework under development for characterising air defense control tasks and also for characterising the larger framework in which such control tasks must be coordinated. The challenge is to produce a formative rather than descriptive or normative model, within which broad logical and temporal constraints can be represented, so revealing possibilities for action as events unfold.
Auditory Warning Signals: New Concepts and Approaches
Authors: Xiao Yan , Seagull F. Jacob
Published: January 2012

The importance of auditory warning signals has long been recognized by designers, yet the design of current auditory warnings are often cited as fundamentally flawed by numerous shortcomings. This symposium, using the medical domain as the context, begins by introducing the status quo and trends in auditory warning design, and discusses the current problems within this setting. We continue with a presentation of the efforts of the International Organization for Standards (ISO) to improve auditory warnings for current and future medical devices. Informative auditory signals are discussed in the final two presentations, focusing first on techniques using “earcons,” “sonification,” in general, and then examining how these continuous and intermittent auditory warnings and informative displays could support the users' tasks.
A Design for Auditory Display
Authors: Blattner Meera M
Published: January 2012

Auditory messages in home, office, and medical environments consist of little more than beeps, bells, and buzzers. Warning signals are particularly inappropriate for these environments because they startle, annoy, but do not inform listeners as to the source of the difficulty. As home automation becomes prevalent, unpleasant sounds will not be tolerated. Earcons are musical sounds that are easy to learn; yet designed to inform listeners of the status of automated systems. We discuss problems such as simultaneous sounds and levels of urgency below.
The VProf Tutor: Teaching MD-11 Vertical Profile Navigation Using GT-ITACS
Authors: Gray Wm. Michael , Chappell Alan R. , Thurmanxy David A. , Palmer Michael T. , Mitchell Christine M.
Published: January 2012

The VProf Tutor is a computer-based intelligent tutoring system (ITS) that teaches the use and understanding of vertical profile navigation modes to MD-11 pilots. This ITS is a proof-of-concept implementation of GT-ITACS (Georgia Tech-Intelligent Tutoring Architecture for Complex Systems). GT-ITACS is a domain- and platform- independent intelligent tutoring system shell designed to train operators of complex-dynamic systems. This paper introduces the features of GT-ITACS, using the VProf Tutor to illustrate the capabilities of the system.