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Virtual reality (VR) and game-based learning strategies have rarely been investigated together with a keen focus on motivational processing. This lack of understanding on motivational support of VR game-based learning has hindered the design of such environments to effectively and efficiently support intended learning processes. The study revealed relationships between learners' motivational processing and perceived game features in a VR learning environment for delivering introductory archaeology content to college students. The first part of the study adopted the complementary concurrent mixed-method design, which applied qualitative results to clarify quantitative findings to delineate motivational support perceived by 40 participants. The second part employed quantitative survey data only from the same sample to reveal perceived game features and relationships between motivational support and game features. Findings suggest that learners' motivational processing was supported by the Confidence and Satisfaction components of the ARCS motivational design model. Additionally, not all motivational components were supported by perceived game features according to multiple regression analyses. The discussion of the findings is focused on in what areas and to what extent multimedia-rich VR elements might compete with game-based learning in the same learning environment for learners' limited cognitive and behavioral learning capacities. [ABSTRACT FROM AUTHOR]

How organizations need to act in order to develop their learning capacities has always been a focal interest of research and practice in the workplace. In practice, an e-learning system is often utilized to foster professional development as it is capable of delivering information and knowledge to individuals across organizations. However, the effect of e-learning systems on fostering the development of learning organizations in South Korean companies remains unsubstantiated by empirical research. Hence, in this study, a total of 327 datasets from three Korean companies (A, B and C) were analyzed to investigate this research question: can utilizing an e-learning system accelerate the process of companies becoming learning organizations? The results showed that only the e-learning systems of Company A and Company C, but not of Company B, facilitated the development of learning organizations. The study concluded that employees' acceptance levels toward e-learning systems must be considered in order to effectively promote long-term implementation of e-learning systems that would lead to the development of learning organizations. [ABSTRACT FROM AUTHOR]

Effective use of multimedia (MM) in instructional design is critical for student learning, especially for large lecture introductory courses. This study used a mixed-method approach to explore the effect of food science supporting course materials that utilized different MM formats, designed with Cognitive Theory of Multimedia Learning (CTML) methods, on cognitive load as explained by perceived mental effort (PME) scores combined with students' perceptions. College students ( n = 182) were randomized into 1 of 3 MM groups: audio + text + graphics (Group 1-ATG); text + graphics (Group 2-TG); or video + audio + text + graphics (Group 3-VATG). Participants answered a demographic survey and prior knowledge questionnaire before viewing 3 food science supporting course materials (that is, food laws, quality assurance, and sensory tests) and completed the PME instrument and open-ended questions online in a noncontrolled setting. For quantitative data, PME scores were compared among MM groups and content types using analysis of variance (ANOVA). For qualitative data, content analysis was applied to identify extraneous cognitive load (ECL)-related descriptors from students' open-ended question responses, which were used to explain quantitative survey findings. Overall, students in Group 2-TG had lower PME scores than Groups 1-ATG and 3-VATG ( P < 0.05) and participants in Group 2-TG provided less ECL-related comments than those in the other 2 groups. Across MM groups, students showed higher PME scores after reviewing the quality assurance course material ( P < 0.05). Additionally, despite higher PME scores, students from Groups 1-ATG and 3-VATG would take another course with these MM formats. Practical Implications This study investigated the appropriate use of CTML methods when designing supporting course materials with various MM formats for asynchronous learning. The findings showed that instructors should consider different effects of MM formats when designing online course materials. In addition, instructors should apply mixed-method approach to evaluate effects of MM design on students' perceived cognitive load levels that cannot be fully understood with only quantitative survey data. [ABSTRACT FROM AUTHOR]

In order to inform educators in higher education on the integration of Web 2.0 applications for engaging and effective learning experiences, this survey study compared the use and acceptance of Web 2.0 applications between American and Korean college students through the lens of cultural differences. Undergraduate students were recruited to participate in this study in the U. S. and the South of Korea, producing 183 usable responses. Targeting six Web 2.0 applications (blogs, instant messenger, online social communities/Facebook, online video sharing/YouTube, online video & audio conference/Skype, and social virtual communities/Second Life) the survey investigated five categories of technology acceptance based on the Unified Theory of Acceptance and Use of Technology. Significant differences on utilization level and the anxiety level for using them were found in numerous Web 2.0 applications. Korean students responded that most Web 2.0 applications are apprehensive for them to use when compared to their counterparts in the U.S.. The study further discussed the observed differences based on cultural theories and their implications on Web 2.0 learning technology integration. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents simulation study on the effects of the cross-sectional area at the merging region and high pressure compressed airflow rate on the flow energy merger, and their optimum adjustments for the change in the compressed air pressure (P air) in the hybrid pneumatic power system (HPPS). The simulation of energy mixing and merging processes was performed for an innovative energy merger pipe in which the open angle (A) of the air storage tank’s throttle valve and the contraction of the cross-sectional area (CSA) at the merging region of the energy merger pipe can be adjusted for changes in P air. The simulations were carried out using computational fluid dynamics (CFD). The results showed that the exhaust-gas recycling efficiency and the merger flow energy are significantly dependent on the optimal adjustments of A and CSA for the change in P air. The optimal conditions for higher exhaust-gas recycling efficiency and the best energy merging process can be achieved at A of around 25–100% and a CSA of around 5–40% for a full range of P air. Under these conditions, the exhaust-gas recycling efficiency reached approximately 80–88%. Therefore, a vehicle equipped with an HPPS can achieve a level of efficiency that is approximately 40% higher than that of conventional vehicles. [Copyright &y& Elsevier]

A hybrid pneumatic power system (HPPS) is integrated by an internal combustion engine (ICE), a high efficiency turbine, an air compressor and an energy merger pipe, which can not only recycle and store exhaust gas energy but also convert it into useful mechanical energy. Moreover, it can make the ICE operate in its optimal state of maximum efficiency; and thus, it can be considered an effective solution to improve greatly the exhaust emissions and increase the overall energy efficiency of the HPPS. However, in this system, the flow energy merger of both high pressure compressed air flow and high temperature exhaust gas flow of the ICE greatly depends on the merging capability of the energy merger pipe. If the compressed air pressure (Pair ) at the air inlet is too high, smooth transmission and mixture of the exhaust gas flow are prevented, which will interfere with the operation condition of the ICE. This shortcoming is mostly omitted in the previous studies. The purpose of this paper is to study the effect of the level of Pair and the contraction of cross-section area (CSA) at the merging position on the flow energy merger and determine their optimum adjustments for a better merging process by using computation fluid dynamics (CFD). In addition, the CFD model was validated on the basis of the experimental data, including the temperature and static pressure of the merger flow at the outlet of the energy merger pipe. It was found that the simulation results were in good agreement with the experimental data. The simulation results show that exhaust gas recycling efficiency and merger flow energy are significantly dependent on the optimum adjustment of the CSA for changes in Pair . Under these optimum adjustments, the exhaust gas recycling efficiency can reach about 83%. These results will be valuable bases to research and design the energy merger pipe of the HPPS. [Copyright &y& Elsevier]

OBJECTIVE:: To determine whether safety culture factors varied across the intensive care units (ICUs) of a single hospital, between nurses and physicians, and to explore ICU nursing directorsʼ perceptions of their personnelʼs attitudes.DESIGN:: Cross-sectional surveys using the Safety Attitudes Questionnaire-ICU version, a validated, aviation industry-based safety culture survey instrument. It assesses culture across six factors: teamwork climate, perceptions of management, safety climate, stress recognition, job satisfaction, and work environment.SETTING:: Four ICUs in one tertiary care hospital.SUBJECTS:: All ICU personnel.MEASUREMENTS AND MAIN RESULTS:: We conducted the survey from January 1 to April 1, 2003, and achieved a 70.2% response rate (318 of 453). We calculated safety culture factor mean and percent-positive scores (percentage of respondents with a mean score of ≥75 on a 0–100 scale for which 100 is best) for each ICU. We compared mean ICU scores by ANOVA and percent-positive scores by chi-square. Mean and percent-positive scores by job category were modeled using a generalized estimating equations approach and compared using Wald statistics. We asked ICU nursing directors to estimate their personnelʼs mean scores and generated ratios of their estimates to the actual scores.Overall, factor scores were low to moderate across all factors (range across ICUs: 43.4–74.9 mean scores, 8.6–69.4 percent positive). Mean and percent-positive scores differed significantly (p < .0083, Bonferroni correction) across ICUs, except for stress recognition, which was uniformly low. Compared with physicians, nurses had significantly lower mean working conditions and perceptions of management scores. ICU nursing directors tended to overestimate their personnelʼs attitudes. This was greatest for teamwork, for which all director estimates exceeded actual scores, with a mean overestimate of 16%.CONCLUSIONS:: Significant safety culture variation exists across ICUs of a single hospital. ICU nursing directors tend to overestimate their personnelʼs attitudes, particularly for teamwork. Culture assessments based on institutional level analysis or director opinion may be flawed. [ABSTRACT FROM AUTHOR]

This research has designed a new hybrid-electric system, which is characterized by two mechanisms: internal-combustion engine energy-distribution mechanism and dual energy-integration mechanism. The internal-combustion engine energy-distribution mechanism comprises a first pulley-set and a second pulley-set, whereby it is possible to adjust its radius ratio and change the output load according to the road-surface, output speed and corresponding load to maintain an optimal operating state of engine for a given generator rotational-speed. In this way, the engine can function in its optimal state. For a dual energy-integration mechanism, any power source can be individually actuated by the electric motor and the power transmitted from the internal-combustion engine energy-distribution mechanism. Moreover, a one-way clutch can prevent the actuated power source from reversion, so any output power source will not be affected by any inactive power. Also, two input power-sources can be integrated into a bigger power source via the dual energy-integration mechanism, thus resulting in twice the output energy and obtaining the necessary tractive power. A dynamic equation is therefore derived from this system to obtain the flow direction for the power source. Furthermore, dynamic equations of various system components can be established by the modularized software Matlab/simulink, and fuzzy logic is used to control and develop this system''s dual energy-integration mechanism as a control strategy. It can be learnt from the system simulation that, after the engine''s energy is distributed by the controller of the dual energy-integration mechanism, subjected to a deceleration ratio of the first pulley-set of the internal-combustion engine distribution mechanism and added to the generator torque transmitted from the second pulley-set, the engine can maintain an optimum state under various operating conditions. [Copyright &y& Elsevier]

Improvements in engine-manufacturing technology have gradually increased the thermal efficiencies of engines as well as the burning temperature and pressure of fuels within the cylinders. Accordingly, greater heat dissipation are required. However, the volume of the radiators is constrained by the configuration of the engines, leading to excessive internal resistance in the engine-cooling system. Therefore, water pumps in engines are prone to cavitation, and air bubbles are likely to permeate into the anti-freeze, thereby severely reducing the performance, reliability and service life of the engines. Ethylene glycol (EG) is added to the radiator of some vehicles in cold areas to reduce the solidification point of the coolant and prevent freezing. This study probes the effects of the percentage of anti-freeze added to the cooling water in a water pump in an engine on the water-supply capability and cavitation temperature, whether air or burnt gas is present in the system. The results of this study have revealed that engines have a higher tolerance to air bubbles at lower rates of rotation. At a given fixed rotational speed, the tolerable cavitation temperature of an engine''s water pump will fall slowly as the amount of air bubbles increases. [Copyright &y& Elsevier]

This new system promises an internal-combustion engine that always maintains optimal operating conditions. The system comprises two parts: (1) an internal-combustion power-distribution device and (2) an integrated design involving the engine and electronic motor. The internal-combustion power-distribution device provides an engine capable of constantly operating in an optimal fashion, minimizing emissions and maximizing thermal-efficiency. The electric motor can generate extra power. Notably, the integrated torque design comprises three helical gears. This design can release the power of the engine or electric motor separately, or can integrate these two different powers into a hybridized power system. [Copyright &y& Elsevier]

If future trials of acute lung injury/acute respiratory distress syndrome are to be rigorous, informative, and successful, a number of key design issues need to be considered. First, appropriate sample size and entry criteria must be selected. The present definitions of acute lung injury/acute respiratory distress syndrome are arbitrary and select a broad, heterogeneous patient population in which treatment effects may often be small, requiring much larger sample sizes than those of previous trials. The alternative approach, selecting a subset of patients in whom a larger benefit is anticipated, is potentially hazardous because the subset selection criteria are unproven. Second, it must be ensured that the therapy is tested against current best methods of care. To ensure that a study is considered current at completion, investigators should anticipate that recent evidence at study commencement will be considered standard at study completion. Up-to-date evidence-based medicine should therefore be encouraged for all enrolled patients and, probably, protocolized in unblinded studies. Multiple novel therapies can also be tested, but care must be paid to the particular study design choice. Third, appropriate outcomes must be chosen. The traditional end point of 28-day mortality is too short and too crude to capture all relevant patient and societal outcomes. Thus, consideration of survival over a longer duration, coupled with assessment of quality of life, functional status, and morbidity, is essential. Fourth, the study must comply with new standards for the protection of human subjects. Protecting human subjects' rights and ensuring patient safety in subjects who are critically ill and who are rarely able to provide fully informed consent is a significant challenge. However, it is essential that new studies comply with required standards without becoming so burdensome that they cannot reasonably be completed. [ABSTRACT FROM AUTHOR]

Corneal topography is used to measure the anterior surface of the cornea. It is conventionally represented as radial slope, radial curvature, and elevation. In this paper, we introduce the application of mean curvature mapping as an alternative representation of the corneal topography. The purpose is to improve the detection of keratoconus and other diseases characterized by local increase in corneal curvature. Both simulated keratoconus cornea and real keratoconus data exported from the corneal topography system were analyzed. Four representations of corneal topography were generated and compared. It was found that mean curvature mapping provided the most precise cone location in simulated keratoconus. In both actual and simulated keratoconus cases, the appearance of the cone-like distortion is more consistent on mean curvature maps. Mean curvature mapping may improve the detection and localization of corneal shape abnormalities. [ABSTRACT FROM AUTHOR]

We generate time series from scale-free networks based on a finite-memory random walk traversing the network. These time series reveal topological and functional properties of networks via their temporal correlations. Remarkably, networks with different node-degree mixing patterns exhibit distinct self-similar characteristics. In particular, assortative networks are transformed into time series with long-range correlation, while disassortative networks are transformed into time series exhibiting anticorrelation. These relationships are consistent across a diverse variety of real networks. Moreover, we show that multiscale analysis of these time series can describe and classify various physical networks ranging from social and technological to biological networks according to their functional origin. These results suggest that there is a unified dynamical mechanism that governs the structural organization of many seemingly different networks [ABSTRACT FROM AUTHOR]

The discovery, synthesis, and optimization of compound 1from a high-throughput screening hit to highly potent and selective peroxisome proliferator-activated receptor δ (PPARδ) agonists are reported. The synthesis and structure−activity relationship in this series are described in detail. On the basis of a general schematic PPAR pharmacophore model, scaffold 1was divided into headgroup, linker, and tailgroup and successively optimized for PPAR activation using in vitro PPAR transactivation assays. A (2-methylphenoxy)acetic acid headgroup, a flexible linker, and a five-membered heteroaromatic center ring with two hydrophobic aryl substituents were required for efficient and selective PPARδ activation. The fine-tuning of these aryl substituents led to an array of highly potent and selective compounds such as compound 38c, displaying an excellent pharmacokinetic profile in mouse. In an in vivo acute dosing model, selected members of this array were shown to induce the expression of pyruvate dehydrogenase kinase-4 (PDK4) and uncoupling protein-3 (UCP3), genes that are known to be involved in energy homeostasis and regulated by PPARδ in skeletal muscle. [ABSTRACT FROM AUTHOR]

Abstract: This research coats a commercial TiO2 nanoparticle Degussa P25 with good roundness and size uniformity on an indium tin oxide (ITO) glass substrate and to be photoelectrical electrode by electrophoresis deposition. It combined with dye N719, electrolyte / and counter-electrode of Pt layer to produce dye-sensitized solar cells (DSSCs). Through the electrophoretic technique, a multilayer film of an appropriate thickness is deposited in the suspension containing TiO2 nanoparticles and isopropanol. In this process, electric current, voltage, and the number of deposition cycles are well controlled to obtain a single TiO2 film of around 3.3μm thick. Stacking is then performed to obtain a multilayer-typed TiO2 film of around 12μm thick. As the sintering temperature reaches 400°C, the prepared multilayer TiO2 film with a good compactness can increase the dye adsorption capability of the thin film and enhance its adsorption percentage. In addition, the heat treatment will transfer a portion of the rutile crystalline into the anatase crystalline, resulting in better material properties for DSSCs application. DSSCs produced are exposed to metal halide lamp and their energy conversion efficiency is measured. The I–V curve of the produced DSSCs shows that it has an excellent energy conversion efficiency of 6.9%. [Copyright &y& Elsevier]

Klebsiella pneumoniaeisolates harboring KPC enzymes have been identified in many geographical areas since 2001. Numerous problems exist in the detection and treatment of patients with such isolates. The clinical characteristics and molecular epidemiology associated with 12 randomly chosen patients in whom these enzymes were detected by molecular methods are described. This is the first description of the identification of carbapenem-resistant K. pneumoniaeisolates harboring KPC β-lactamases at the Veterans Administration Hospital in New Jersey (VA NJHCS). Because recognition of carbapenem resistance in K. pneumoniaedue to KPC enzymes can only be achieved by molecular methods, detection in the Clinical Microbiology Laboratory by routine methods will continue to be difficult, leading to dilemmas in treatment. [ABSTRACT FROM AUTHOR]

We present in vivo human total retinal blood flow measurements using Doppler Fourier domain optical coherence tomography (OCT). The scan pattern consisted of two concentric circles around the optic nerve head, transecting all retinal branch arteries and veins. The relative positions of each blood vessel in the two OCT conic cross sections were measured and used to determine the angle between the OCT beam and the vessel. The measured angle and the Doppler shift profile were used to compute blood flow in the blood vessel. The flows in the branch veins was summed to give the total retinal blood flow at one time point. Each measurement of total retinal blood flow was completed within 2 s and averaged. The total retinal venous flow was measured in one eye each of two volunteers. The results were 52.90±2.75 and 45.23±3.18 μl/min, respectively. Volumetric flow rate positively correlated with vessel diameter. This new technique may be useful in the diagnosis and treatment of optic nerve and retinal diseases that are associated with poor blood flow, such as glaucoma and diabetic retinopathy. [ABSTRACT FROM AUTHOR]

There is considerable interest in new methods for the assessment of retinal blood flow for the diagnosis of eye diseases. We present in vivo normal human volumetric retinal flow measurement using Fourier domain Doppler optical coherence tomography. We used a dual-plane scanning pattern to determine the angle between the blood flow and the scanning beam in order to measure total flow velocity. Volumetric flow in each blood vessel around the optic nerve head was integrated in one cardiac cycle in each measurement. Measurements were performed in the right eye of one human subject. The measured venous flow velocity ranged from 16.26 mm/s to 29.7 mm/s. The arterial flow velocity ranged from 38.35 mm/s to 51.13 mm/s. The total retinal venous and arterial flow both added up to approximately 54 μl/min. We believe this is the first demonstration of total retinal blood flow measurement using the OCT technique. [ABSTRACT FROM AUTHOR]