bluuebunny/crossref_metadata_2025 huggingface dataset:
Alternating Incubation Effects in the Generation of Category Exemplars
Authors: Smith Steven M. , Gerkens David R. , Angello Genna
Published: May 2015

Four experiments tested the forgetting fixation hypothesis of incubation effects, comparing continuous vs. alternating generation of exemplars from three different types of categories. In two experiments, participants who listed as many members as possible from two different categories produced more responses, and more novel responses, when they alternated back and forth between the two categories, as compared to continuous uninterrupted listing from each of the two categories. This incubation effect was not found in Experiment 1, when participants were given taxonomic categories (birdsandclothing) for the generation task, but was found in Experiment 2 with sense impression categories (cold thingsandheavy things), and in Experiment 3 withad hoccategories (equipment you take campingandfattening foods). A similar incubation effect was observed in Experiment 4 when a non‐verbal task was given between category generation tasks, but only for flexibly defined categories. The results suggest that forgetting from one alternating listing period to the next in the form of altering category cue representations was consistent with the observed incubation effects. Thesealternating incubationeffects have implications for understanding cognitive processes that underlie creative cognition.
Intraoperative passive knee kinematics during total knee arthroplasty surgery
Authors: Young Kathryn L. , Dunbar Michael J. , Richardson Glen , Astephen Wilson Janie L.
Published: May 2015

Surgical navigation systems for total knee arthroplasty (TKA) surgery are capable of capturing passive three‐dimensional (3D) angular joint movement patterns intraoperatively. Improved understanding of patient‐specific knee kinematic changes between pre and post‐implant states and their relationship with post‐operative function may be important in optimizing TKA outcomes. However, a comprehensive characterization of the variability among patients has yet to be investigated. The objective of this study was to characterize the variability within frontal plane joint movement patterns intraoperatively during a passive knee flexion exercise. Three hundred and forty patients with severe knee osteoarthritis (OA) received a primary TKA using a navigation system. Passive kinematics were captured prior to (pre‐implant), and after prosthesis insertion (post‐implant). Principal component analysis (PCA) was used to capture characteristic patterns of knee angle kinematics among patients, to identify potential patient subgroups based on these patterns, and to examine the subgroup‐specific changes in these patterns between pre‐ and post‐implant states. The first four extracted patterns explained 99.9% of the diversity within the frontal plane angle patterns among the patients. Post‐implant, the magnitude of the frontal plane angle shifted toward a neutral mechanical axis in all phenotypes, yet subtle pattern (shape of curvature) features of the pre‐implant state persisted. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1611–1619, 2015.
Statistical modeling to characterize relationships between knee anatomy and kinematics
Authors: Smoger Lowell M. , Fitzpatrick Clare K. , Clary Chadd W. , Cyr Adam J. , Maletsky Lorin P. , Rullkoetter Paul J. , Laz Peter J.
Published: May 2015

The mechanics of the knee are complex and dependent on the shape of the articular surfaces and their relative alignment. Insight into how anatomy relates to kinematics can establish biomechanical norms, support the diagnosis and treatment of various pathologies (e.g., patellar maltracking) and inform implant design. Prior studies have used correlations to identify anatomical measures related to specific motions. The objective of this study was to describe relationships between knee anatomy and tibiofemoral (TF) and patellofemoral (PF) kinematics using a statistical shape and function modeling approach. A principal component (PC) analysis was performed on a 20‐specimen dataset consisting of shape of the bone and cartilage for the femur, tibia and patella derived from imaging and six‐degree‐of‐freedom TF and PF kinematics from cadaveric testing during a simulated squat. The PC modes characterized links between anatomy and kinematics; the first mode captured scaling and shape changes in the condylar radii and their influence on TF anterior–posterior translation, internal‐external rotation, and the location of the femoral lowest point. Subsequent modes described relations in patella shape and alta/baja alignment impacting PF kinematics. The complex interactions described with the data‐driven statistical approach provide insight into knee mechanics that is useful clinically and in implant design. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1620–1630, 2015.
Edible films and coatings based on biodegradable residues applied to acerolas (Malpighia punicifolia L.)
Authors: Ferreira Mariana SL , Fai Ana Elizabeth C , Andrade Cristina T , Picciani Paulo H , Azero Edwin G , Gonçalves Édira CBA
Published: May 2015

BACKGROUND

This study aimed to produce and characterize edible films and coatings from fruit and vegetable residue (FVR) flour and potato peel (P) flour. Two coating approaches (immersion and film) were studied on the quality of acerolas.

RESULTS

Film‐forming solutions (FFS) presented a viscoelastic behavior and a gelation process occurring at 70 °C. Maximum density (1.018 g cm−3), viscosity (44.404 cP) and starch content were obtained for FFS based on 8% FVR flour with 4% P flour. This same film presented enhanced mechanical properties such as tensile strength and elongation at break (0.092 MPa and 36% respectively). Solubility of the films averaged 87%, demonstrating high hydrophilicity. Improved performance was obtained for film‐packaged acerolas, which exhibited an increase in shelf life of 50% compared with control fruits. A lower loss of weight was observed for these samples by about 30–57% compared with control fruits, but minor modifications of pH, titratable acidity and soluble solid content occurred during storage.

CONCLUSION

This study demonstrated the potential of FVR flour for edible coating and film formulation. Practical application on acerolas constituted a motivating route to evaluate and optimize this process; however, microbiological and sensory analyses are necessary to assess the material acceptability and safety. © 2015 Society of Chemical Industry
Frontotemporal Dementia‐Like Syndrome Following Recall of Childhood Sexual Abuse
Authors: Cohen Lisa J. , Brody David
Published: May 2015

Numerous psychopathological syndromes have been attributed to posttraumatic stress, both at the time of the trauma and many years later. To date, however, there is little literature on pseudodementia as a delayed traumatic stress response. The authors present a case history of a 50‐year‐old woman who developed severe cognitive impairment following retrieval of previously forgotten memories of childhood sexual abuse. Her cognitive condition deteriorated rapidly and dramatically. Neuropsychological assessment and clinical presentation led to a diagnosis of frontotemporal dementia (vs. corticobasal degeneration). Detailed neurologic and medical evaluations could not identify any underlying physical cause. Her condition progressively worsened over 9 months, at which point memantine, an N‐methyl‐D‐aspartate receptor antagonist, was begun. The patient regained full functioning over the next year. Although an organic cause could not be ruled out, it was likely that recovery of traumatic memories was contributory to the patient's condition, as ongoing psychotherapy had begun 1 year into the course. If additional cases with similar presentations are reported, such cases would corroborate the notion that persistent, severe, and reversible cognitive impairment constitutes a previously unrecognized and atypical posttraumatic response.
Patient‐perceived benefit of sialendoscopy as measured by the Glasgow Benefit Inventory
Authors: Meier Bue A. , Holst René , Schousboe Lars P.
Published: May 2015

Objectives/Hypothesis

Evaluate the patient‐perceived effect of sialendoscopy on patients with obstructive symptoms from the salivary glands.

Study Design

Retrospectively identified cohort used for a prospective study of all consecutive patients at the Department of Otorhinolaryngology at Vejle Hospital, Vejle, Denmark, March 2009 to December 2013.

Methods

By chart review we recorded the patient's age, gender, date of the sialendoscopy, type of gland, sialolithiasis, successful extraction of sialolithiasis, stenosis of salivary ducts, dilation, type of saliva, and surgeon. The follow‐up was done by applying the Glasgow Benefit Inventory questionnaire by letter and telephone.

Results

There were 130 sialendoscopies performed on 116 patients. Of these, 24 patients were excluded due to subsequent surgery. Thus, 92 patients were eligible, of whom 80 responded, giving an 87% response rate. The Glasgow Benefit Inventory score had a predicted overall mean of 13.4 (95% confidence interval: 9.9 to 17.2). Significant positive outcomes by multiple regression were the presence of stones (P = 0.015) and examination of the parotid gland (P = 0.041).

Conclusions

Overall, there is a significant patient‐perceived benefit from sialendoscopy, which is comparable to the benefit from tonsillectomy. The benefit is significantly higher if stones are found than not and for examination of the parotid gland as compared to the submandibular gland.

Level of Evidence

4 Laryngoscope, 125:1874–1878, 2015
Cost‐effectiveness of liver transplantation in methylmalonic and propionic acidemias
Authors: Li Meng , Dick Andre , Montenovo Martin , Horslen Simon , Hansen Ryan
Published: May 2015

Propionic acidemia (PA) and classical methylmalonic acidemia (MMA) are rare inborn errors of metabolism that can cause early mortality and significant morbidity. The mainstay of disease management is lifelong protein restriction. As an alternative, liver transplantation (LT) may improve survival, quality of life, and prevent further neurological deterioration. The aim of our study was to estimate the incremental costs and outcomes of LT versus nutritional support in patients with early‐onset MMA or PA. We constructed a Markov model to simulate and compare life expectancies, quality‐adjusted life years (QALYs), and lifetime direct and indirect costs for a cohort of newborns with MMA or PA who could either receive LT or be maintained on conventional nutritional support. We conducted a series of 1‐way and probabilistic sensitivity analyses. In the base case, LT on average resulted in 1.5 more life years lived, 7.9 more QALYs, and a savings of $582,369 for lifetime societal cost per individual compared to nutritional support. LT remained more effective and less costly in all 1‐way sensitivity analyses. In the probabilistic sensitivity analysis, LT was cost‐effective at the $100,000/QALY threshold in more than 90% of the simulations and cost‐saving in over half of the simulations. LT is likely a dominant treatment strategy compared to nutritional support in newborns with classical MMA or PA. Liver Transpl 21:1208‐1218, 2015. © 2015 AASLD.
Optimizing informed consent in living liver donors: Evaluation of a comprehension assessment tool
Authors: Gordon Elisa J. , Mullee Jack , Butt Zeeshan , Kang Joseph , Baker Talia
Published: May 2015

Adult‐to‐adult living liver donation is associated with considerable risks with no direct medical benefit to liver donors (LDs). Ensuring that potential LDs comprehend the risks of donation is essential to medically and ethically justify the procedure. We developed and prospectively evaluated the initial psychometrics of an “Evaluation of Donor Informed Consent Tool” (EDICT) designed to assess LDs' comprehension about the living donation process. EDICT includes 49 true/false/unsure items related to LD informed consent. Consecutive LDs undergoing evaluation at 1 academic medical center from October 2012 to September 2014 were eligible for participation in pretest/posttest interviews. Medical records were reviewed for postdonation complications. Twenty‐seven LDs participated (96% participation rate). EDICT demonstrated good internal consistency reliability at pretest, 2 days before donating (Cronbach's α = 0.78), and posttest, 1 week after donating (α = 0.70). EDICT scores significantly increased over time (P = 0.01) and demonstrated good test‐retest reliability (r = 0.68; P < 0.001). EDICT was associated with race/ethnicity (P = 0.02) and relationship to the recipient (P = 0.01; pretest), and income (P = 0.01) and insurance (P = 0.01; posttest), but not with decisional conflict, preoperative preparedness, satisfaction, or decisional regret (pretest and posttest). Donor complications did not impact postdonation EDICT scores. In conclusion, EDICT has promising measurement properties and may be useful in the evaluation of informed consent for potential LDs. Liver Transpl 21:1270‐1279, 2015. © 2015 AASLD.
The recipient celiac trunk as an alternative to the native hepatic artery for arterial reconstruction in adult liver transplantation
Authors: Dokmak Safi , Aussilhou Béatrice , Landi Filippo , Dondéro Fédérica , Termos Salah , Paugam‐Burtz Cathérine , Durand François , Belghiti Jacques
Published: May 2015

During liver transplantation (LT), the recipient hepatic artery (RHA) cannot always be used, and alternatives include aortohepatic conduits and the splenic artery (SA). We report our experience with arterial reconstruction on the recipient celiac trunk (RCT), which has rarely been described. Since January 2013, we have been using the RCT when the RHA could not be used. All cases were discussed in a multidisciplinary LT meeting, and arterial patency or anomalies were systemically viewed with computed tomography (CT) scan. The RCT was used after section‐ligation of all celiac trunk collaterals. Until May 2014, the RHA could not be used in 11/139 (8%) patients who underwent LT. Postoperative arterial patency was assessed by serial Doppler ultrasound and CT scan. The advantages and disadvantages of the different arterial conduits were evaluated. The RCT was used in 7/11 (64%) patients. Mean follow‐up was 10 (6‐15) months. The patency rate was 100%, and 1 patient with associated portal shunting died at day 20 from septic complications. No related gastric or splenic complications were encountered. The RCT could not be used in 4 patients with reconstruction on the SA (n = 2), infrarenal (n = 1), and supraceliac aorta (n = 1). The patency rate was 75%. One patient with SA conduit and portal shunting developed pancreatitis/anastomotic pseudoaneurysm with secondary rupture. An emergency infrarenal conduit was created, which was later embolized because of infected pseudoaneurysms. Although the literature reports a higher risk of thrombosis with aortohepatic conduits, no long‐term results are available for the SA conduits, and only 1 report is available for the RCT. In conclusion, this study shows that the RCT is a good alternative to the RHA and can be used in two‐thirds of patients with inadequate RHA flow. Liver Transpl 21:1133‐1141, 2015. © 2015 AASLD.
A multicenter study of 30 days complications after deceased donor liver transplantation in the model for end‐stage liver disease score era
Authors: Parikh Anup , Washburn Kenneth W. , Matsuoka Lea , Pandit Urvashi , Kim Jennifer E. , Almeda Jose , Mora‐Esteves Cesar , Halff Glenn , Genyk Yuri , Holland Bart , Wilson Dorian J. , Sher Linda , Koneru Baburao
Published: May 2015

Knowledge of risk factors for posttransplant complications is likely to improve patient outcomes. Few large studies of all early postoperative complications after deceased donor liver transplantation (DDLT) exist. Therefore, we conducted a retrospective, cohort study of 30‐day complications, their risk factors, and the impact on outcomes after DDLT. Three centers contributed data for 450 DDLTs performed from January 2005 through December 2009. Data included donor, recipient, transplant, and outcome variables. All 30‐day postoperative complications were graded by the Clavien‐Dindo system. Complications per patient and severe (≥ grade III) complications were primary outcomes. Death within 30 days, complication occurrence, length of stay (LOS), and graft and patient survival were secondary outcomes. Multivariate associations of risk factors with complications and complications with LOS, graft survival, and patient survival were examined. Mean number of complications/patient was 3.3 ± 3.9. At least 1 complication occurred in 79.3%, and severe complications occurred in 62.8% of recipients. Mean LOS was 16.2 ± 22.9 days. Graft and patient survival rates were 84% and 86%, respectively, at 1 year and 74% and 76%, respectively, at 3 years. Hospitalization, critical care, ventilatory support, and renal replacement therapy before transplant and transfusions during transplant were the significant predictors of complications (not the Model for End‐Stage Liver Disease score). Both number and severity of complications had a significant impact on LOS and graft and patient survival. Structured reporting of risk‐adjusted complications rates after DDLT is likely to improve patient care and transplant center benchmarking. Despite the accomplished reductions in transfusions during DDLT, opportunities exist for further reductions. With increasing transplantation of sicker patients, reduction in complications would require multidisciplinary efforts and institutional commitment. Pretransplant risk characteristics for complications must factor in during payer contracting. Liver Transpl 21:1160‐1168, 2015. © 2015 AASLD.
A lap joint simulant laboratory test method of aluminium alloys
Authors: Zimmer A. , Oltra R. , Le T. M. L.
Published: May 2015

A lap joint simulant cavity (LJSC) with a gap thickness of 200 μm has been developed to test corrosion of assembled coated aluminium alloys. The LJSC was instrumented with electrodes allowing simultaneous pH and potential measurements in 0.5 M NaCl solution. Assuming the outer part of the LJSC is electrochemically inactive (painted sheet) it was confirmed that in free corroding conditions the pH inside the LJSC tends more towards alkalinisation. On the opposite, if the outer part of the LJSC is electrochemically active (unpainted sheet) the pH inside the LJSC tends towards an acidic value.
Multidetector‐ThF3 as a Novel Tool for the Investigation of Solution Properties of Amphiphilic Block Copolymers
Authors: Ngaza Nyashadzashe , Brand Margaretha , Pasch Harald
Published: May 2015

In this study, multidetector Thermal FFF (ThF3) is utilized to study amphiphilic block copolymers in different selective and nonselective solvents. Depending on the solvent quality and the polymer concentration, amphiphilic block copolymers can form aggregates or micelles; the blocks can adopt different coil conformations. ThF3 is chosen because of the noninvasive nature of the technique that will not destroy the conformations that amphiphilic block copolymers can adopt in selected solvents. The effect of different polymer–solvent systems on the diffusion and thermal diffusion coefficients, and the resultant separation, is studied. It is found that, depending on the solvent, the macromolecules adopt extended coil or partially collapsed coil conformations. Experimental conditions are identified where the block copolymers behave similar to one of their parent homopolymers. For the first time, it has been shown that ThF3 is a unique tool to study the solution properties and the coil conformations of amphiphilic copolymers and to relate this information to the fractionation behavior of the polymers.

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Operant Behavioral Economics
Authors: Foxall Gordon R.
Published: May 2015

The aims of this special issue are to introduce managerial economists to a school of behavioral economics they may not yet have encountered by way of accounts by leading researchers of its basic tenets, methods, and applications. This overview introduces the papers by setting them in the context of the development of operant behavioral economics. Copyright © 2015 John Wiley & Sons, Ltd.
Driven by Consequences: The Multiscale Molar View of Choice
Authors: Baum William M.
Published: May 2015

In the Multiscale Molar View of behavior, all behavior is seen as choice and is measured as time allocation. Because time is limited, activities compete for the limited time available. When Phylogenetically Important Events (PIEs) that ultimately affect fitness and ontogenetic proxies of these PIEs occur as consequences of an activity, they drive time spent in that activity. Time allocation is studied in the laboratory with concurrent payoff schedules, in which two or more schedules operate simultaneously. The generalized matching law describes choice in relation to relative consequences. It has been verified for food and other PIEs and for pairs of variable‐interval schedules and variable‐interval schedules paired with variable‐ratio schedules. Because behavior produces consequences in the environment and those consequences in turn affect behavior, the environmental feedback functions and behavioral functional relations may be characterized as a feedback system. When different activities produce different consequences, choice depends also on the substitutability of the consequences. When consequences are perfectly substitutable, exclusive preference may occur, but when they are imperfectly substitutable, partial preferences may occur. Choice may become a dilemma pitting impulsivity against self‐control when consequences are not stationary with respect to time. Evaluated in short timeframes, an activity may be strongly induced by its consequences, but evaluated in long timeframes, its consequences may be extremely negative; such an activity (e.g., using cocaine or lying) is a bad habit. A good habit (e.g., tooth brushing or helping others) presents the opposite conflict: bad consequences in short timeframes and positive consequences in long timeframes. Research on choice between good and bad habits may reveal factors that increase time spent in good habits relative to time spent in bad habits. The Multiscale Molar View helps to clarify various complexities that underlie choice viewed as time allocation. Copyright © 2015 John Wiley & Sons, Ltd.
Social Cooperation and Self‐control
Authors: Rachlin Howard
Published: May 2015

Social cooperation and self‐control are, in common, coherent patterns of choice extended in social space and time—as opposed to a series of case‐by‐case choices of locally higher‐valued alternatives. Patterns of social cooperation and self‐control may evolve (in the face of locally higher‐valued alternatives) by pattern selection, a process in behavioral evolution (i.e., learning) corresponding to multilevel selection in biological evolution. Individual tendencies toward social cooperation (or altruism) and self‐control may be measured by social and delay discount functions, which take the same (hyperbolic) form in the two cases. (An Appendix discusses the use of hypothetical rewards in behavioral economic research.) Copyright © 2015 John Wiley & Sons, Ltd.
The Behavioral and Neuroeconomics of Reinforcer Pathologies: Implications for Managerial and Health Decision Making
Authors: Jarmolowicz David P. , Reed Derek D. , DiGennaro Reed Florence D. , Bickel Warren K.
Published: May 2015

Although humans do not always respond rationally, decades of behavioral economic research have brought order to these irrational patterns of responding, particularly in individuals whose maladaptive behavior and the neurobiological dysregulation that presumably undergirds it directly impact their health (drug addiction and obesity). These findings have given rise to a new paradigm, reinforcer pathologies. Specifically, poor health decisions are consistently related to an inability to value the future and an overvaluation of specific unhealthy rewards (drugs, cake, etc.). The current review briefly describes these robust areas of research with the goal of adapting the present findings to improve staff performance. Copyright © 2015 John Wiley & Sons, Ltd.
An Experimental Study of Intertemporal Choices: The Case of Customer Relationship Management
Authors: Fagerstrøm Asle , Aksnes Dag , Arntzen Erik
Published: May 2015

An in‐basket task scenario was arranged where 10 participants were required to prioritize between a short‐term task and a task that was related to a long term‐project. The participants were given an in‐basket task that should be solved within 40 min. They were interrupted by an incoming telephone call five times during the task period (after 7, 14, 21, 28, and 35 min). The interruption was related to a long‐term project linked to a bonus payment at the end of the year. Results indicate that 6 out of 10 participants spent less time on an interruption if it occurred late in the 40 min in‐basket task session. This supports the assumptions that, in customer relationship management activities, individuals work on smaller tasks whose outcomes occur sooner rather than on tasks with larger but later outcomes. Hence, the results support the idea that discounted utility of outcomes plays an important role in understanding choices in an organizational setting. Results from the present study indicate that technological drift can be understood within the hyperbolic discounting framework. Copyright © 2015 John Wiley & Sons, Ltd.
How Does Probability Impact Consumers' Choice? The Case of Online Reviews
Authors: Fagerstrøm Asle , Ghinea Gheorghita , Sydnes Lars
Published: May 2015

Consumers are frequently in situations that include evaluating the probability of the outcome of a particular choice. It is, therefore, essential to analyze how probability influences choice in order to fully understand consumer behavior. This paper investigates how probability discounting contributes to the understanding of the impact of online reviews on consumer choice. An experiment with 25 participants was conducted. Participants were presented with an online shopping scenario in which they had to choose between two online shops: one with (positive) customer reviews (on delivery reliability and customer service) and higher product prices, while the other had lower prices, but no customer reviews at all. We employed a titration procedure over sales price for the web shop without customer reviews; this was run over seven probability conditions. The point where participants switched between one web shop and another was recorded, and the probability discounting factors were calculated. The results highlight that online reviews are indicators of successful online transactions (i.e., intention to buy) and therefore function as choice benchmarks. In the light of these results, the paper presents practical implications, as well as directions for future research. Copyright © 2015 John Wiley & Sons, Ltd.
Behavioral Economics and the Analysis of Consumption and Choice
Authors: Hursh Steven R. , Roma Peter G.
Published: May 2015

Behavioral economics (BE) in psychology focuses on the application of traditional microeconomics concepts to the study of behavior, particularly the cross‐species analysis of consumption broadly defined and choice. Here, we review key concepts such as demand, substitution, and complementarity within a behavioral psychology framework, novel behavioral economics analysis techniques for quantifying demand elasticity and patterns of choice behaviors, and broader implications for organizational decision‐making and empirical public policy. Copyright © 2015 John Wiley & Sons, Ltd.
Operant Behavioral Economics for E‐mail Marketing: An Experiment Based on the Behavioral Perspective Model Testing the Effectiveness of Motivational Operation, Utilitarian and Informational Stimuli
Authors: Sigurdsson Valdimar , Hinriksson Hinrik , Menon R.  G. Vishnu
Published: May 2015

The e‐mail marketing literature is limited and scattered and in a search for a more systematic approach to research. The few published studies mostly consist of indirect (attitudinal) measures of behavior instead of a direct measurement of the actual variables of interest—consumer economic choice. Furthermore, published research does not focus on motivational operations despite marketing's emphasis on needs, wants, and personalized marketing. In the current paper, we extend the examination of the Behavioral Perspective Model as a conceptual system for managerial decision making in e‐mail marketing. The experiment tested the applicability of motivational operations and utilitarian and informational contingencies for e‐mail marketing for a hardware and home improvement chain selling bicycle helmets. A motivational‐segmentation analysis of the marketing database was performed prior to the experiment based on the target product appropriateness for consumers. After the segmentation, different types of e‐mails based on altered utilitarian contingencies or a combination of utilitarian and informational contingencies were sent to two groups from the same marketing database of registered consumers interested in receiving special offers. The results showed that the e‐mail marketing's effectiveness were greatest when motivational‐based segmentation and economical (utilitarian) contingencies were applied. Copyright © 2015 John Wiley & Sons, Ltd.
Optimal Strategy and Business Models: A Control Theory Approach
Authors: Johnson Peter , Foss Nicolai J.
Published: May 2015

This study picks up on earlier suggestions that control theory may further the study of strategy. Strategy can be formally interpreted as an idealized path optimizing heterogeneous resource deployment to produce maximum financial gain. Using standard matrix methods to describe the firm Hamiltonian, it is possible to formalize useful notions of a business model, resources, and competitive advantage. The business model that underpins strategy may be seen as a set of constraints on resources that can be interpreted as controls in optimal control theory. Strategy then might be considered to be the control variable of firm path, suggesting in turn that the firm's business model is the codification of the application of investment resources used to control the strategic path of value realization. Copyright © 2015 John Wiley & Sons, Ltd.
On a reaction diffusion equation with nonlinear time‐nonlocal source term
Authors: Ahmad Bashir , Alsaedi Ahmed , Kirane Mokhtar
Published: May 2015

In this article, we prove the local existence of a unique solution to a nonlocal in time and space evolution equation with a time nonlocal nonlinearity of exponential growth. Moreover, under some suitable conditions on the initial data, it is shown that local solutions experience blow‐up. The time profile of the blowing‐up solutions is also presented. Copyright © 2015 John Wiley & Sons, Ltd.
Algebro‐geometric constructions of the Wadati‐Konno‐Ichikawa flows and applications
Authors: Li Zhu , Geng Xianguo , Guan Liang
Published: May 2015

With the aid of Lenard recursion equations, we derive the Wadati–Konno–Ichikawa hierarchy. Based on the Lax matrix, an algebraic curve
of arithmetic genus n is introduced, from which Dubrovin‐type equations and meromorphic function φ are established. The explicit theta function representations of solutions for the entire WKI hierarchy are given according to asymptotic properties of φ and the algebro‐geometric characters of
. Copyright © 2015 John Wiley & Sons, Ltd.
Existence results for a class of nonlocal problems involving p(x)‐Laplacian
Authors: Allaoui Mostafa , El Amrouss Abdel Rachid , Ourraoui Anass
Published: May 2015

This paper is concerned with the existence of solutions to a class of p(x)‐Kirchhoff‐type equations with Dirichlet boundary data as follows:

urn:x-wiley:mma:media:mma3524:mma3524-math-0001

By means of variational methods and the theory of the variable exponent Sobolev spaces, we establish some conditions on the existence of solutions. Copyright © 2015 John Wiley & Sons, Ltd.
Three‐parameter shear wave inversion in MR elastography of incompressible transverse isotropic media: Application to in vivo lower leg muscles
Authors: Guo Jing , Hirsch Sebastian , Scheel Michael , Braun Jürgen , Sack Ingolf
Published: May 2015

Purpose

To develop and demonstrate MR elastography (MRE) for the measurement of three independent viscoelastic constants of skeletal muscle according to the theory of linear elasticity of incompressible materials with transverse isotropy (TI).

Methods

Three‐dimensional multifrequency MRE was applied to soleus, gastrocnemius, and tibialis anterior muscles in 10 healthy volunteers. The rotational wave fields were solved for complex‐valued viscoelastic parameters μ12, μ13, and E3 corresponding to two shear moduli (within the planes of isotropy and symmetry of TI materials) and Young's modulus (along the principal fiber axis).

Results

Anisotropy was represented by the inequality μ12 < μ13 < 1/3E3 considering storage and loss properties of the soleus and gastrocnemius muscles, whereas storage shear moduli of tibialis were indistinguishable. Storage moduli were: 1.06 ± 0.12, 1.33 ± 0.10, 6.92 ± 0.95 kPa (soleus); 0.90 ± 0.11, 1.30 ± 0.15, 8.22 ± 1.37 kPa (gastrocnemius); 1.26 ± 0.16, 1.27 ± 0.11, 9.29 ± 1.42 kPa (tibialis), for μ12, μ13, and E3, respectively. The muscles were different in their μ12 and E3 values, whereas μ13 was less sensitive to the muscle type. Leg differences were observed in the soleus and gastrocnemius muscles.

Conclusion

Recovery of the full elasticity tensor in incompressible TI materials is feasible by three‐dimensional inversion of the time‐harmonic shear wave equation. The method is potentially useful for the clinical evaluation of skeletal muscle anisotropy. Magn Reson Med 75:1537–1545, 2016. © 2015 Wiley Periodicals, Inc.
A simple and efficient strategy for solving very large‐scale generalized cable‐trench problems
Authors: Vasko Francis J. , Landquist Eric , Kresge Gregory , Tal Adam , Jiang Yifeng , Papademetris Xenophon
Published: May 2015

Vasko et al., Comput Oper Res 29 (2002), 441–458 defined the cable‐trench problem (CTP) as a combination of the Shortest Path and Minimum Spanning Tree Problems. Specifically, let be a connected weighted graph with specified vertex (referred to as the root), length for each , and positive parameters and . The CTP is the problem of finding a spanning tree of such that is minimized, where is the total length of the spanning tree and is the total path length in from to all other vertices of . Recently, Jiang et al., Proceedings of MICCAI 6893 (2011), 528–536 modeled the vascular network connectivity problem in medical image analysis as an extraordinarily large‐scale application of the generalized cable‐trench problem (GCTP). They proposed an efficient solution based on a modification of Prim's algorithm (MOD_PRIM), but did not elaborate on it. In this article, we formally define the GCTP, describe MOD_PRIM in detail, and describe two linearly parallelizable metaheuristics which significantly improve the performance of MOD_PRIM. These metaheuristics are capable of finding near‐optimal solutions of very large GCTPs in quadratic time in . We also give empirical results for graphs with up to 25,001 vertices. © 2015 Wiley Periodicals, Inc. NETWORKS, Vol. 67(3), 199–208 2016
Friction and wear studies of polyetherimide composites under oscillating sliding condition against steel cylinder
Authors: Harsha A.P. , Wäsche Rolf , Hartelt Manfred
Published: May 2015

Tribological properties of neat polyetherimide (PEI), glass, carbon fiber, and solid lubricants filled PEI composites are presented in this article. The aim of this study was to investigate the friction and wear properties of these composites under dry oscillating sliding condition at room temperature (RT) as well as at elevated temperature (120°C). The polymer specimens were made to oscillate against steel cylinder as a counterpart. The friction and wear properties of PEI and composites were strongly influenced by the temperature. Incorporation of carbon fiber in the PEI matrix has increased the wear rate at RT, while at elevated temperature this trend was opposite. Abrasive action of carbon fibers has severely damaged the counterpart and resulted in accelerated wear of the composite at RT. Solid lubricants filled (PTFE, MoS2, graphite) along with glass fiber is beneficial in improving the friction and wear performance of the PEI composite at RT, whereas at elevated temperature wear performance was deteriorated. Tribological performance of neat PEI and glass fiber composite was similar with each other at RT. Scanning electron micrographs and optical micrographs of the worn polymer specimens and the steel cylinders was used to study the possible wear mechanisms. The present test results were also compared with data available on the reciprocating wear of PEI and composites in the literature and trends have been reported. POLYM. COMPOS., 38:48–60, 2017. © 2015 Society of Plastics Engineers
Disparities in the prenatal detection of critical congenital heart disease
Authors: Hill G. D. , Block J. R. , Tanem J. B. , Frommelt M. A.
Published: May 2015

Objectives

Prenatal diagnosis of critical congenital heart disease, which requires surgical or catheter intervention in the first 30 days of life, allows for delivery at a specialized center and can reduce preoperative morbidity and mortality. We sought to identify the risk factors for a missed prenatal diagnosis of critical congenital heart disease.

Methods

Patients presenting to the Children's Hospital of Wisconsin with critical congenital heart disease from 2007 to 2013 were included. Those with a prenatal diagnosis were compared with those with a postnatal diagnosis.

Results

The cohort included 535 patients with prenatal diagnosis made in 326 (61%). The prenatal diagnostic rate improved from 44% in 2007 to 69% in 2013. Independent factors associated with a postnatal diagnosis were a lesion that required a view other than a four chamber view to make the diagnosis (p < 0.0001), absence of another organ system anomaly (p < 0.0001), and living in a higher poverty (p = 0.02) or lower population density communities (p = 0.002).

Conclusions

While the prenatal diagnostic rate for critical congenital heart disease is improving, those living in impoverished or rural communities are at highest risk of not having a diagnosis made prenatally. Interventions to improve prenatal detection of congenital heart disease should target these vulnerable areas. © 2015 John Wiley & Sons, Ltd.
Large diameter multiwall nanotubes of MgB2: Structural aspects and stability of superconducting nanotubular magnesium boride
Authors: Baňacký Pavol , Noga Pavol , Szöcs Vojtech , Noga Jozef
Published: May 2015

Based on a theoretical study, we demonstrated that magnesium boride nanotubes can reach the same stability as bulk MgB2 structure. However, most stable nanotubular forms are not structurally derived from mixed triangular–hexagonal structural motifs of a single layer sheet, which is thought to be the 2D precursor form of all boron nanotubes. MgB2 multiwall nanotubular structures that are derived from multilayer MgB2 slabs with honeycomb B‐networks in hexagonal lattices are more stable. The results of an ab initio study of multilayer slabs of MgB2 show that a 25‐layer slab approaches the stability of bulk MgB2. The critical parameter of the corresponding multiwall nanotubes is the inner diameter; the calculated value is ∼32.6 nm, which is independent of the number of walls. The outer diameters of 25‐wall nanotubes are ∼51 nm, and terminal Mg atoms are located on the outer surfaces of the nanotubes. The electronic band structures of MgB2‐multiwall nanotubes (MgB2MWNT) correspond to the band structure character and topology of superconducting bulk MgB2. The results confirm that the quasi‐1D superconductor MgB2MWNT is a stable structure and can be synthesized.
Investigation of structural, morphological and electrical properties of APCVD vanadium oxide thin films
Authors: Papadimitropoulos Georgios , Kostis Ioannis , Trantalidis Stelios , Tsiatouras Athanasios , Vasilopoulou Maria , Davazoglou Dimitris
Published: May 2015

Vanadium oxide films were chemically vapor deposited (CVD) on oxidized Si substrates covered with CVD tungsten (W) thin films and on glass substrates covered with indium tin oxide (ITO) films, using vanadium(V) oxy‐tri‐isopropoxide (C9H21O4V) vapors. X‐ray diffraction (XRD) measurements showed that the deposited films were composed of a mixture of vanadium oxides; the composition was determined mainly by the deposition temperature and less by the precursor temperature. At temperatures up to 450 °C the films were mostly composed by monoclinic VO2. Other peaks corresponding to various vanadium oxides were also observed. X‐ray microanalysis confirmed the composition of the films. The surface morphology was studied with atomic force microscopy (AFM) and scanning electron microscopy (SEM). These measurements revealed that the morphology strongly depends on the used substrate and the deposition conditions. The well‐known metal‐insulator transition was observed near 75 °C for films mostly composed by monoclinic VO2. Films deposited at 450 °C exhibited two transitions one near 50 °C and the other near 60 °C possibly related to the presence of other vanadium phases or of important stresses in them. Finally, the vanadium oxide thin films exhibited significant sensory capabilities decreasing their resistance in the presence of hydrogen gas with response times in the order of a few seconds and working temperature at 40 °C. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Channel adaptive output back‐off setting of non‐linear power amplifiers for high throughput multi‐spot beam satellite systems
Authors: Katona Zoltán
Published: May 2015

In order to increase the satellite capacity for high throughput systems, the feeder link frequencies are gradually moved to higher bands, such as the Q/V‐bands, where more bandwidth is available. Therefore, more spectrum shall be available for the user links at lower frequencies, such as in Ka‐band. However, the rain attenuation on the feeder links becomes a limiting issue because of the higher frequencies. It is thus important to find link adaptation, or in other words channel adaptive techniques that can overcome this issue, such as smart gateway diversity or adaptive coding and modulation. This paper, however, introduces and describes a novel patented technique: channel adaptive output back‐off (OBO) setting. This technique can be applied on any terrestrial or satellite link, in which a non‐linear power amplifier is operated in multicarrier mode and the transmission channel experiences time varying attenuation. As a consequence, this technique can be applied, for example, both on the feeder uplink and on the feeder downlink of multi‐spot beam satellite networks. However, due to several reasons, the present paper analyzes its performance only on the feeder downlink. According to the performed analysis, channel adaptive OBO setting can provide around 4.5 dB signal‐to‐noise and interference ratio improvement in case of deep rain fading compared with the conventional fixed OBO operation. This improvement reduces the outage by around 17% on the end‐to‐end return link. As a consequence, the feeder downlink and the total return link become much more robust against deep rain fading. Copyright © 2015 John Wiley & Sons, Ltd.
Towards modelling perfect forward secrecy in two‐message authenticated key exchange under ephemeral‐key revelation
Authors: Yang Zheng , Yang Wu , Zhu Lingyun , Zhang Daigu
Published: May 2015

We examine the recently introduced CF and CF‐perfect forward secrecy (PFS) models for two‐message authenticated key exchange (TMAKE) by Cremers et al., where the difference between CF and CF‐PFS model is that the CF formulates the weak PFS (wPFS), whereas the CF‐PFS formulates the PFS. The CF model is claimed by Cremers et al. to be strictly stronger the previous extended Canetti‐Krawczyk (eCK) model. However, we notice that the implication relations among CF, CF‐PFS, eCK and eCK‐PFS model have not been completely studied. Based on TMAKE, we particularly show that CF model and eCK model imply each other under random oracle model. Moreover, we provide a new result on the generic security strengthening transformation (compiler) for building CF‐PFS‐secure TMAKE protocols. In contrast to a previous work, we show that it is possible to apply the transformation to all CF‐secure AKE protocols including all eCK‐secure TMAKE protocols in the random oracle model, without restricting to a small specific class of Diffie–Hellman key based protocols. Copyright © 2015 John Wiley & Sons, Ltd.
Epitaxial Bi2FeCrO6 Multiferroic Thin Film as a New Visible Light Absorbing Photocathode Material
Authors: Li Shun , AlOtaibi Bandar , Huang Wei , Mi Zetian , Serpone Nick , Nechache Riad , Rosei Federico
Published: May 2015

Ferroelectric materials have been studied increasingly for solar energy conversion technologies due to the efficient charge separation driven by the polarization induced internal electric field. However, their insufficient conversion efficiency is still a major challenge. Here, a photocathode material of epitaxial double perovskite Bi2FeCrO6 multiferroic thin film is reported with a suitable conduction band position and small bandgap (1.9–2.1 eV), for visible‐light‐driven reduction of water to hydrogen. Photoelectrochemical measurements show that the highest photocurrent density up to −1.02 mA cm−2 at a potential of −0.97 V versus reversible hydrogen electrode is obtained in p‐type Bi2FeCrO6 thin film photocathode grown on SrTiO3 substrate under AM 1.5G simulated sunlight. In addition, a twofold enhancement of photocurrent density is obtained after negatively poling the Bi2FeCrO6 thin film, as a result of modulation of the band structure by suitable control of the internal electric field gradient originating from the ferroelectric polarization in the Bi2FeCrO6 films. The findings validate the use of multiferroic Bi2FeCrO6 thin films as photocathode materials, and also prove that the manipulation of internal fields through polarization in ferroelectric materials is a promising strategy for the design of improved photoelectrodes and smart devices for solar energy conversion.
Corrosion Behavior of Al2O3‐C Refractories with Casting Mould Meniscus Slags at 1 550 °C
Authors: Kumar Anup , Khanna Rita , Ikram‐ul‐Haq Mohammad , Spink John , Sahajwalla Veena
Published: May 2015

The degradation behavior of alumina (10–20 wt%) carbon refractories was investigated during high temperature (1 550 °C) contact with a ternary casting mould meniscus slag containing 50% MnO, 25% SiO2, and 25% Al2O3 and a binary slag containing 40% MnO and 60% SiO2. Using the sessile drop approach, the transient progress of corrosion reactions was investigated as a function of time and refractory composition. An in‐depth characterization and analysis of reacted assemblies was carried out using optical and scanning electron microscopy (SEM). Optical micrographs showed a significant penetration of both slags within the refractory substrate, with very little slag remaining behind after 15 min of contact. The depth of penetration of ternary slag was found to increase with carbon concentration in the refractory. An all‐round corrosion was observed with extensive refractory degradation over a period of time. Corrosion was determined to a great extent by dissolution reactions in the interfacial region; alumina dissolution from the refractory resulted in the formation of needle‐like corundum crystallites which transformed to a cohesive network of faceted corundum crystals on extended contact. A number of reaction products containing Mn and Si were also observed.