bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical disease and lung lesions in calves experimentally inoculated with Histophilus somni five days after metaphylactic administration of tildipirosin or tulathromycin
Authors: Confer Anthony W. , Snider Timothy A. , Taylor Jared D. , Montelongo Marie , Sorensen Nicholas J.
Published: March 2016

OBJECTIVE To compare clinical disease and lung lesions in calves experimentally inoculated with Histophilus somni 5 days after metaphylactic administration of tildipirosin or tulathromycin.

ANIMALS Twenty-four 3-month-old Holstein and Holstein-crossbreed steers.

PROCEDURES Calves were randomly allocated to 3 groups of 8 calves. On day 0, calves in group 1 received tildipirosin (4 mg/kg, SC), calves in group 2 received tulathromycin (2.5 mg/kg, SC), and calves in group 3 received isotonic saline (0.9% NaCl) solution (1 mL/45 kg, SC; control). On day 5, calves were inoculated with 10 mL of a solution containing H somni strain 7735 (1.6 × 109 CFUs/mL, intrabronchially; challenge). Calves were clinically evaluated on days 5 through 8 and euthanized on day 8. The lungs were grossly evaluated for evidence of pneumonia, and bronchial secretion samples underwent bacteriologic culture.

RESULTS The mean clinical score for each group was significantly increased 12 hours after challenge, compared with that immediately before challenge, and was significantly lower for tildipirosin-treated calves on days 6, 7, and 8, compared with those for tulathromycin-treated and control calves. The mean percentage of lung consolidation for tildipirosin-treated calves was significantly lower than those for tulathromycin-treated and control calves. Histophilus somni was isolated from the bronchial secretions of some tulathromycin-treated and control calves but was not isolated from tildipirosin-treated calves.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that metaphylactic administration of tildipirosin to calves 5 days prior to H somni challenge prevented subsequent culture of the pathogen from bronchial secretions and was more effective in minimizing clinical disease and lung lesions than was metaphylactic administration of tulathromycin.
Effect of the C(3)-Substituent in Verdazyl Radicals on their Profluorescent Behavior
Authors: Eusterwiemann Steffen , Eckert Hellmut , Strassert Cristian A. , Doltsinis Nikos L. , Daniliuc Constantin G. , Doerenkamp Carsten C , Klabunde Sina , Stegemann Linda , Matuschek David , Studer Armido
Published: March 2016

Methods for the detection of reactive intermediates such as transient radicals are important in organic chemistry, polymer chemistry, biology or medicine. Along these lines we recently reported that 1,5-diphenyl-6-oxo verdazyl radicals can be used as fluorescent spin sensors. In situ
generated C-centered radicals are efficiently trapped by the verdazyls, which in turn undergo transformation from a paramagnetic non-fluorescent state to a diamagnetic fluorescent state. Whereas the N-phenyl substituent in the spin probes is of high importance for obtaining profluorescent
behavior, the effect of the C(3)-substituent has not been investigated to date. We herein present the synthesis and characterization of various 1,5-diphenyl-6-oxo-verdazyl radicals bearing differently hybridized C-substituents at the C(3) position. Steady-state and time-resolved fluorescence
spectroscopy in solution and in the solid state along with time-dependent density functional theory (TDDFT) calculations reveal that a C(3)-aryl substituent is crucial for obtaining fluorescence after spin trapping. In addition, it is shown that the emission wavelength of the C(3)-aryl substituted verdazyl derivatives can be tuned by selective destabilization of the HOMO and the LUMO.
Probing Mechanisms of Photochemical Reactions: How to Teach a Young Dog Old Tricks
Authors: Bochet Christian G.
Published: March 2016

The mechanism of photochemical reactions can be difficult to study because of the very short-lived intermediates involved. State-of-the art ultrafast spectroscopic tools can be used to probe these processes, but we will show in this account that old-fashioned techniques, such as the
determination of quantum yields, the measurement of isotope effects or the use of triplet quenchers and sensitizers still can give a significant insight into the mechanism of photochemical reactions.
Using Polymer Modification and Rejuvenators to Improve the Performance of High Reclaimed Asphalt Pavement Mixtures
Authors: Mogawer Walaa S. , Austerman Alexander J. , Kluttz Robert , Puchalski Sebastian
Published: March 2016

Softer binders have been used to compensate for the stiffness of reclaimed asphalt pavement (RAP) binders in mixtures; however, several studies have shown that asphalt rejuvenators can allow more RAP to be incorporated in mixtures than can softer binders alone. Nevertheless, rejuvenators are not specified by some state agencies because of potential rutting-related concerns. Therefore, the use of polymer modified asphalt (PMA) binder was evaluated to ascertain if it can remedy any rutting performance degradation while maintaining or improving the cracking characteristics of the mixtures. The objective was to produce mixtures with high RAP content that perform similar to or better than an all-virgin-material control mixture. The effect of five asphalt rejuvenators on the performance of a 50% RAP surface-layer mixture was evaluated relative to rutting and cracking. The results illustrated that the rejuvenators degraded the rutting resistance of the 50% RAP mixture, although the use of PMA binders remedied these degradations. The rejuvenators improved the fatigue cracking resistance of the 50% RAP mixture to a level higher than did the all-virgin control mixture and also the 50% RAP mixture with softer binder alone. Overall, the data indicated that a combination of an asphalt rejuvenator and a PMA binder was required to yield a high RAP mixture with similar or better performance than a similar conventional mixture.
Cold In-Place Recycling Moisture-Related Design and Construction Considerations for Single or Multiple Component Binder Systems
Authors: Cox Ben C. , Howard Isaac L. , Campbell Colin S.
Published: March 2016

In recent years, cold in-place recycling (CIR) has gained momentum because of its economic, performance, and sustainability characteristics; as a result CIR markets are likely to expand into, for example, higher traffic routes. To further understand how to continue improving CIR for existing applications as well as future applications, better techniques are needed with regard to interfacing design and construction. Moisture is one key area in which design and construction are often disconnected. This study’s objective, therefore, was to evaluate the moisture (and associated early-age strength and stability) aspects of CIR, particularly within a framework that could consider hydraulic cement, bituminous emulsion, or combinations of both binders. A universal design framework that accommodates any binder or combination thereof while representing early-age field conditions has advantages for agencies, not only in its reasonable characterization of construction processes, but also in its facilitation of competition and creativity in the process of selecting materials and proportions. This study was organized in three phases. Phase 1 documented moisture instrumentation of a cement CIR project. Data were successfully obtained throughout compaction and curing and were used in Phases 2 and 3 alongside supplemental field and laboratory testing. Phase 2 evaluated moisture’s role in compaction; Phase 3 evaluated moisture–strength and moisture–stability relationships for various curing protocols. Phase 2 concluded that high (>6%) moisture content, typical of Proctor compaction, is generally unnecessary. Thus, Proctor compaction is discouraged in favor of a fixed design moisture content. Phase 3 concluded that humid (35% to 50% humidity) and dry 40°C oven curing protocols are candidates for universal CIR design.
Finite Element Approach to Assess the Benefits of Asphalt Solar Collectors
Authors: Dakessian Lala , Harfoushian Hagop , Habib David , Chehab Ghassan R. , Saad George , Srour Issam
Published: March 2016

Asphalt solar collectors (ASCs) consist of a pipe network embedded in the surface asphalt layer of an asphalt pavement. As fluid circulates in the pipes, it absorbs heat from the pavement and cools it down. While previous research has concentrated on studying ASC parameters independently, this study combined them in a comprehensive model to evaluate the potential of ASCs to harvest energy from pavements and mitigate the negative impact of their high surface temperatures. For that purpose, a finite element model of an ASC was developed to predict the temperature profile of the pavement, pipes, and circulating fluid. The model was validated under field conditions with two flow configurations: a closed loop system with reservoir and a single-pass system. The single-pass system was shown to yield a higher efficiency than a closed loop system would (21.9% versus 10.9%). Once validated, the model was used to simulate ASC water and pavement temperatures during representative days of four seasons for a specific climate. The finite element model predicted that a single-pass ASC would increase water temperatures by an average of 4.0°C, 7.5°C, 10.2°C, and 13.6°C and reduce pavement surface temperatures by an average of 0.5°C, 0.7°C, 2.5°C, and 3.2°C throughout the days in winter, autumn, spring, and summer, respectively. These reductions resulted in a 3-year extension of the pavement lifetime for a prescribed set of traffic, structural, climatic, and materials conditions. The potential energy gain and service life extension were used to conduct an economic analysis, which estimated a 5-year payback period of the ASC.
A Comparative Analysis of Productivity among Organic and Non-Organic farms in the West Mamprusi District of Ghana
Authors: Issaka Yakubu , Antwi Moses , Tawia Gladys
Published: March 2016

The study was conducted in organic and conventional crop farms in the West Mamprusi District of the Northern Region of Ghana. The key issue the study sought to determine was whether there are productivity differences among organic and conventional crop farms and what factors account for these differences. The results indeed revealed that there are productivity differences among organic and conventional crop farms. However, both had negative total factor productivity growth, largely accounted for by a negative technical change over the period considered. The technical efficiency change, however, was positive for both but much higher for organic farms than conventional farms. More importantly, the study revealed that the type of agriculture practiced by farmers is not the most critical problem confronting farmers as indicated by the negative total productivity growth for both. Major constraints confronting farmers that need to be addressed include better organization on the farmers’ front, improved access to extension and improved access to farm inputs. These challenges notwithstanding, the study revealed that organic agriculture has the potential, in the long run, to achieve much more progress in total factor productivity, compared to conventional agriculture, if the right conditions exist for its uptake and optimal application.
Obtaining Atomic Matrix Elements from Vector Tune-Out Wavelengths Using Atom Interferometry
Authors: Fallon Adam , Sackett Charles
Published: March 2016

Accurate values for atomic dipole matrix elements are useful in many areas of physics, and in particular for interpreting experiments such as atomic parity violation. Obtaining accurate matrix element values is a challenge for both experiment and theory. A new technique that can be applied to this problem is tune-out spectroscopy, which is the measurement of light wavelengths where the electric polarizability of an atom has a zero. Using atom interferometry methods, tune-out wavelengths can be measured very accurately. Their values depend on the ratios of various dipole matrix elements and are thus useful for constraining theory and broadening the application of experimental values. To date, tune-out wavelength measurements have focused on zeros of the scalar polarizability, but in general the vector polarizability also contributes. We show here that combined measurements of the vector and scalar polarizabilities can provide more detailed information about the matrix element ratios, and in particular can distinguish small contributions from the atomic core and the valence tail states. These small contributions are the leading error sources in current parity violation calculations for cesium.
1,4-Bis[(N-acetyl-l-phenylalanyl-glycyl-l-alanyl)aminomethyl]benzene
Authors: Demizu Yosuke , Tsutsui Kohei , Misawa Takashi , Kurihara Masaaki
Published: March 2016

The title compound was prepared by inducing amide bond formation between 1,4-bis(aminomethyl)benzene and tripeptide Ac-Phe-Gly-Ala-OH. The structure of the synthesized compound was determined on the basis of its 1H-nuclear magnetic resonance (NMR), 13C-NMR, and mass spectral data. Furthermore, the compound's preferred structure in solution and calculated conformation are also reported.
Fabrication of Bendable Circuits on a Polydimethylsiloxane (PDMS) Surface by Inkjet Printing Semi-Wrapped Structures
Authors: Sun Jiazhen , Jiang Jieke , Bao Bin , Wang Si , He Min , Zhang Xingye , Song Yanlin
Published: March 2016

In this work, an effective method was developed to fabricate bendable circuits on a polydimethylsiloxane (PDMS) surface by inkjet printing semi-wrapped structures. It is demonstrated that the precured PDMS liquid film could influence the depositing morphology of coalesced silver precursor inkjet droplets. Accordingly, continuous and uniform lines with a semi-wrapped structure were fabricated on the PDMS surface. When the printed silver precursor was reduced to Ag nanoparticles, the fabricated conductive film exhibited good transparency and high bendability. This work presented a facile way to fabricate flexible patterns on a PDMS surface without any complicated modification or special equipment. Meanwhile, an in situ hydrazine reduction of Ag has been reported using the vapor phase method in the fabricating process.
Antimicrobial Nanomaterials Derived from Natural Products—A Review
Authors: Wang Ji , Vermerris Wilfred
Published: March 2016

Modern medicine has relied heavily on the availability of effective antibiotics to manage infections and enable invasive surgery. With the emergence of antibiotic-resistant bacteria, novel approaches are necessary to prevent the formation of biofilms on sensitive surfaces such as medical implants. Advances in nanotechnology have resulted in novel materials and the ability to create novel surface topographies. This review article provides an overview of advances in the fabrication of antimicrobial nanomaterials that are derived from biological polymers or that rely on the incorporation of natural compounds with antimicrobial activity in nanofibers made from synthetic materials. The availability of these novel materials will contribute to ensuring that the current level of medical care can be maintained as more bacteria are expected to develop resistance against existing antibiotics.
Dynamic Tuning of Transmission Wavelength of MEMS-Based Ge Waveguides on a Si Beam
Authors: Hirase Masashi , Nguyen Luan , Fukuda Hiroshi , Ishikawa Yasuhiko , Wada Kazumi
Published: March 2016

Three-dimensional structures of microelectro-mechanical systems (MEMS)-based Ge waveguide on a Si beam were fabricated for dynamic tuning of the fundamental absorption edge of Ge by external stressing. The application of various amounts of external forces up to 1 GPa onto the Si beam shows clear red-shifts in the absorption edge of Ge waveguides on the Si beam by ~40 nm. This shift was reproduced by the deformation potential theory, considering that mode of propagation in the Ge waveguide. The wavelength tuning range obtained makes it possible to cover the whole C-band of optical communication, indicating it to be a promising approach to electro-absorption Ge modulators to get them to work with a broader wavelength range than previously reported.
Decline in Performance of Biochemical Reactors for Sulphate Removal from Mine-Influenced Water is Accompanied by Changes in Organic Matter Characteristics and Microbial Population Composition
Authors: Mirjafari Parissa , Baldwin Susan
Published: March 2016

Successful long-term bioremediation of mining-influenced water using complex organic matter and naturally-occurring microorganisms in sub-surface flow constructed wetlands requires a balance between easily and more slowly degrading material. This can be achieved by combining different types of organic materials. To provide guidance on what mixture combinations to use, information is needed on how the ratio of labile to recalcitrant components affects the degradation rate and the types of microbial populations supported. To investigate this, different ratios of wood and hay were used in up-flow column bioreactors treating selenium- and sulphate-containing synthetic mine-influenced water. The degradation rates of crude fibre components appeared to be similar regardless of the relative amounts of wood and hay. However, the nature of the degradation products might have differed in that those produced in the hay-rich bioreactors were more biodegradable and supported high sulphate-reduction rates. Microorganisms in the sulphate-reducing and cellulose-degrading inocula persisted in the bioreactors indicating that bio-augmentation was effective. There was a shift in microbial community composition over time suggesting that different microbial groups were involved in decomposition of more recalcitrant material. When dissolved organic carbon (DOC) was over-supplied, the relative abundance of sulphate-reducers was low even through high sulphate-reduction rates were achieved. As DOC diminished, sulphate-reducers become more prevalent and their relative abundance correlated with sulphate concentrations rather than sulphate-reduction rate.
Accuracy of monitors used for blood pressure checks in English retail pharmacies: a cross-sectional observational study
Authors: Hodgkinson James , Koshiaris Constantinos , Martin Una , Mant Jonathan , Heneghan Carl , Hobbs FD Richard , McManus Richard J
Published: March 2016

Background

Free blood pressure (BP) checks offered by community pharmacies provide a potentially useful opportunity to diagnose and/or manage hypertension, but the accuracy of the sphygmomanometers in use is currently unknown.

Aim

To assess the accuracy of validated automatic BP monitors used for BP checks in a UK retail pharmacy chain.

Design and setting

Cross-sectional, observational study in 52 pharmacies from one chain in a range of locations (inner city, suburban, and rural) in central England.

Method

Monitor accuracy was compared with a calibrated reference device (Omron PA-350), at 50 mmHg intervals across the range 0–300 mmHg (static pressure test), with a difference from the reference monitor of +/− 3 mmHg at any interval considered a failure. The results were analysed by usage rates and length of time in service.

Results

Of 61 BP monitors tested, eight (13%) monitors failed (that is, were >3 mmHg from reference), all of which underestimated BP. Monitor failure rate from the reference monitor of +/− 3 mmHg at any testing interval varied by length of time in use (2/38, 5% <18 months; 4/14, 29% >18 months,P= 0.038) and to some extent, but non-significantly, by usage rates (4/22, 18% in monitors used more than once daily; 2/33, 6% in those used less frequently,P= 0.204).

Conclusion

BP monitors within a pharmacy setting fail at similar rates to those in general practice. Annual calibration checks for blood pressure monitors are needed, even for new monitors, as these data indicate declining performance from 18 months onwards.
Electrocardiogram interpretation and arrhythmia management: a primary and secondary care survey
Authors: Begg Gordon , Willan Kathryn , Tyndall Keith , Pepper Chris , Tayebjee Muzahir
Published: March 2016

Background

There is increasing desire among service commissioners to treat arrhythmia in primary care. Accurate interpretation of the electrocardiogram (ECG) is fundamental to this. ECG interpretation has previously been shown to vary widely but there is little recent data.

Aim

To examine the interpretation of ECGs in primary and secondary care.

Design and setting

A cross-sectional survey of participants’ interpretation of six ECGs and hypothetical management of patients based on those ECGs, at primary care educational events, and a cardiology department in Leeds.

Method

A total of 262 primary care clinicians and 20 cardiology clinicians were surveyed via questionnaire. Answers were compared with expert electrophysiologist opinion.

Results

In primary care, abnormal ECGs were interpreted as normal by 23% of responders. ST elevation and prolonged QT were incorrectly interpreted as normal by 1% and 22%, respectively. In cardiology, abnormal ECGs were interpreted as normal by 3%.

Conclusion

ECG provision and interpretation remains inconsistent in both primary and secondary care. Primary care practitioners are less experienced and less confident with ECG interpretation than cardiologists, and require support in this area.
CHAIN RECONNECTIONS OBSERVED IN SYMPATHETIC ERUPTIONS
Authors: Joshi Navin Chandra , Schmieder Brigitte , Magara Tetsuya , Guo Yang , Aulanier Guillaume
Published: March 2016

The nature of various plausible causal links between sympathetic events is still a controversial issue. In this work, we present multiwavelength observations of sympathetic eruptions, associated flares, and coronal mass ejections (CMEs) occurring on 2013 November 17 in two close active regions. Two filaments, i.e., F1 and F2, are observed in between the active regions. Successive magnetic reconnections, caused for different reasons (flux cancellation, shear, and expansion) have been identified during the whole event. The first reconnection occurred during the first eruption via flux cancellation between the sheared arcades overlying filament F2, creating a flux rope and leading to the first double-ribbon solar flare. During this phase, we observed the eruption of overlying arcades and coronal loops, which leads to the first CME. The second reconnection is believed to occur between the expanding flux rope of F2 and the overlying arcades of filament F1. We suggest that this reconnection destabilized the equilibrium of filament F1, which further facilitated its eruption. The third stage of reconnection occurred in the wake of the erupting filament F1 between the legs of the overlying arcades. This may create a flux rope and the second double-ribbon flare and a second CME. The fourth reconnection was between the expanding arcades of the erupting filament F1 and the nearby ambient field, which produced the bi-directional plasma flows both upward and downward. Observations and a nonlinear force-free field extrapolation confirm the possibility of reconnection and the causal link between the magnetic systems.
MECHANISTIC STUDIES ON THE RADIOLYTIC DECOMPOSITION OF PERCHLORATES ON THE MARTIAN SURFACE
Authors: Turner Andrew M. , Abplanalp Matthew J. , Kaiser Ralf I.
Published: March 2016

Perchlorates—inorganic compounds carrying the perchlorate ion (

)—were discovered at the north polar landing site of the Phoenix spacecraft and at the southern equatorial landing site of the Curiosity Rover within the Martian soil at levels of 0.4–0.6 wt%. This study explores in laboratory experiments the temperature-dependent decomposition mechanisms of hydrated perchlorates—namely magnesium perchlorate hexahydrate (Mg(ClO4)2·6H2O)—and provides yields of the oxygen-bearing species formed in these processes at Mars-relevant surface temperatures from 165 to 310 K in the presence of galactic cosmic-ray particles (GCRs). Our experiments reveal that the response of the perchlorates to the energetic electrons is dictated by the destruction of the perchlorate ion (

) and the inherent formation of chlorates (

) plus atomic oxygen (O). Isotopic substitution experiments reveal that the oxygen is released solely from the perchlorate ion and not from the water of hydration (H2O). As the mass spectrometer detects only molecular oxygen (O2) and no atomic oxygen (O), atomic oxygen recombines to molecular oxygen within the perchlorates, with the overall yield of molecular oxygen increasing as the temperature drops from 260 to 160 K. Absolute destruction rates and formation yields of oxygen are provided for the planetary modeling community.
STELLAR ORIGINS OF EXTREMELY 13C- AND 15N-ENRICHED PRESOLAR SIC GRAINS: NOVAE OR SUPERNOVAE?
Authors: Liu Nan , Nittler Larry R. , Alexander Conel M. O’D. , Wang Jianhua , Pignatari Marco , José Jordi , Nguyen Ann
Published: March 2016

Extreme excesses of 13C (12C/13C < 10) and 15N (14N/15N < 20) in rare presolar SiC grains have been considered diagnostic of an origin in classical novae, though an origin in core collapse supernovae (CCSNe) has also been proposed. We report C, N, and Si isotope data for 14 submicron- to micron-sized 13C- and 15N-enriched presolar SiC grains (12C/13C < 16 and 14N/15N < ∼100) from Murchison, and their correlated Mg–Al, S, and Ca–Ti isotope data when available. These grains are enriched in 13C and 15N, but with quite diverse Si isotopic signatures. Four grains with 29,30Si excesses similar to those of type C SiC grains likely came from CCSNe, which experienced explosive H burning occurred during explosions. The independent coexistence of proton- and neutron-capture isotopic signatures in these grains strongly supports heterogeneous H ingestion into the He shell in pre-supernovae. Two of the seven putative nova grains with 30Si excesses and 29Si depletions show lower-than-solar 34S/32S ratios that cannot be explained by classical nova nucleosynthetic models. We discuss these signatures within the CCSN scenario. For the remaining five putative nova grains, both nova and supernova origins are viable because explosive H burning in the two stellar sites could result in quite similar proton-capture isotopic signatures. Three of the grains are sub-type AB grains that are also 13C enriched, but have a range of higher 14N/15N. We found that 15N-enriched AB grains (∼50 < 14N/15N < ∼100) have distinctive isotopic signatures compared to putative nova grains, such as higher 14N/15N, lower 26Al/27Al, and lack of 30Si excess, indicating weaker proton-capture nucleosynthetic environments.
ELECTRON IRRADIATION AND THERMAL PROCESSING OF MIXED-ICES OF POTENTIAL RELEVANCE TO JUPITER TROJAN ASTEROIDS
Authors: Mahjoub Ahmed , Poston Michael J. , Hand Kevin P. , Brown Michael E. , Hodyss Robert , Blacksberg Jordana , Eiler John M. , Carlson Robert W. , Ehlmann Bethany L. , Choukroun Mathieu
Published: March 2016

In this work we explore the chemistry that occurs during the irradiation of ice mixtures on planetary surfaces, with the goal of linking the presence of specific chemical compounds to their formation locations in the solar system and subsequent processing by later migration inward. We focus on the outer solar system and the chemical differences for ice mixtures inside and outside the stability line for H2S. We perform a set of experiments to explore the hypothesis advanced by Wong & Brown that links the color bimodality in Jupiter's Trojans to the presence of H2S in the surface of their precursors. Non-thermal (10 keV electron irradiation) and thermally driven chemistry of CH3OH–NH3–H2O (“without H2S”) and H2S–CH3OH–NH3–H2O (“with H2S”) ices were examined. Mid-IR analyses of ice and mass spectrometry monitoring of the volatiles released during heating show a rich chemistry in both of the ice mixtures. The “with H2S” mixture experiment shows a rapid consumption of H2S molecules and production of OCS molecules after a few hours of irradiation. The heating of the irradiated “with H2S” mixture to temperatures above 120 K leads to the appearance of new infrared bands that we provisionally assign to SO2and CS. We show that radiolysis products are stable under the temperature and irradiation conditions of Jupiter Trojan asteroids. This makes them suitable target molecules for potential future missions as well as telescope observations with a high signal-to-noise ratio. We also suggest the consideration of sulfur chemistry in the theoretical modeling aimed at understanding the chemical composition of Trojans and KOBs.
COMPARISON OF IMPLICIT SCHEMES TO SOLVE EQUATIONS OF RADIATION HYDRODYNAMICS WITH A FLUX-LIMITED DIFFUSION APPROXIMATION: NEWTON–RAPHSON, OPERATOR SPLITTING, AND LINEARIZATION
Authors: Tetsu Hiroyuki , Nakamoto Taishi
Published: March 2016

Radiation is an important process of energy transport, a force, and a basis for synthetic observations, so radiation hydrodynamics (RHD) calculations have occupied an important place in astrophysics. However, although the progress in computational technology is remarkable, their high numerical cost is still a persistent problem. In this work, we compare the following schemes used to solve the nonlinear simultaneous equations of an RHD algorithm with the flux-limited diffusion approximation: the Newton–Raphson (NR) method, operator splitting, and linearization (LIN), from the perspective of the computational cost involved. For operator splitting, in addition to the traditional simple operator splitting (SOS) scheme, we examined the scheme developed by Douglas & Rachford (DROS). We solve three test problems (the thermal relaxation mode, the relaxation and the propagation of linear waves, and radiating shock) using these schemes and then compare their dependence on the time step size. As a result, we find the conditions of the time step size necessary for adopting each scheme. The LIN scheme is superior to other schemes if the ratio of radiation pressure to gas pressure is sufficiently low. On the other hand, DROS can be the most efficient scheme if the ratio is high. Although the NR scheme can be adopted independently of the regime, especially in a problem that involves optically thin regions, the convergence tends to be worse. In all cases, SOS is not practical.
Increasing the Adaptivity of an Intelligent Tutoring System with Educational Data Mining: A System Overview
Authors: Jugo Igor , Kovačić Božidar , Slavuj Vanja
Published: March 2016

Intelligent Tutoring Systems (ITSs) are inherently adaptive e-learning systems usually created for teaching well-defined domains (e.g., mathematics). Their objective is to guide the student towards a predefined goal such as completing a lesson, task, or mastering a skill. Defining goals and guiding students is more complex in ill-defined domains where the expert defines the model of the knowledge domain or the students have freedom to follow their own path through it. In this paper we present an overview of our systems architecture that integrates the ITS with data mining tools and performs a number of educational data mining processes to increase the adaptivity and, consequently, the efficiency of the ITS.
Application of the Multimedia Teaching System Based on Real-time Shooting and Production in Martial Art Course
Authors: Wang Yunsong , Qi Aili , Cui Fangfang
Published: March 2016

as higher education goes deep continuously, teaching method has become an important research topic of teaching theory in recent years. Multimedia teaching is one of methods in teaching system. On this basis, this paper develops and designs a multimedia teaching system which can achieve shooting and production at any time, and applies it to teach Martial Art course. Besides, computer technology is applied to design an operable system and construct multimedia teaching system for Martial Art course. Then, by example verification of students in Martial Art class of a college and statistical analysis of data, preliminary trial of multimedia teaching is achieved in practical application. Thus, this paper verifies that multimedia teaching system which can achieve shooting and production at any time can improve teaching quality, and further expounds the function and significance of multimedia teaching method from learning attitude and learning effect.
Communities of Practice in Transition Economies
Authors: Vajjhala Narasimha Rao
Published: March 2016

Communities of Practice (CoPs) are informal groups of individuals sharing knowledge and experience within or outside an organization. CoPs can help organizations, especially Small- and Medium-sized Enterprises (SMEs) with limited financial and human resources improve efficiency and productivity by leveraging knowledge resources in the organization. Transition economies have different social and economic conditions as compared to developing and developed countries. The success of CoPs in SMEs located in transition economies depends to a certain extent on the social and cultural factors in transition economies. This chapter explores the factors contributing to the success of CoPs as well as challenges that CoPs face in transition economies. This chapter explores the role of national and organizational culture on the functioning of CoPs in SMEs in transition economies. The objective of this chapter is to develop a framework that could be applied to CoPs in transition economies. This chapter also identifies the factors that might limit the work of CoPs in the context of innovation in SMEs in transition economies.
Mentoring Programs as a Basis for Creating Communities of Practices in Tourism
Authors: Črnjar Kristina , Hrgović Ana-Marija Vrtodušić
Published: March 2016

The connection between educational institutions and tourism organizations is of great importance in the time of a turbulent and competitive labor market. The labor market requires employees with knowledge and high skills that can be used in everyday work. Human capital is a building block of a sustainable, competitive, and innovative tourism organization. Retention of employees with key knowledge, experience, and skills and the transfer of that knowledge to new employees, when resources are limited, is becoming of great importance. Mentoring is a learning mechanism where a process of social participation results in the transfer of knowledge and skills. Accordingly, the aim of this chapter is to suggest a mentoring framework, taking into account the different interested parties: educational institutions, tourism enterprises, mentors, and students. The results of this chapter could be used for improvement of the existing mentoring practice.
The Emergence of Women Entrepreneurs and Communities of Practice within the Global Context
Authors: Tomos Florica , Clark Andre , Thurariaj Saraswathy , Balan Oana Cristina , Turner David
Published: March 2016

This chapter aims to explore the emergence of women entrepreneurs across the Globe. Moreover, the authors analyse the existent research and knowledge about Communities of Practice (CoPs) and information communication technologies (ICTs) and raise awareness of their role in supporting women entrepreneurs. The authors attempted systematic and unsystematic literature review to investigate the emergence of women entrepreneurs across the Globe and the role of Communities of Practice. There was an unprecedented increase in women entrepreneurship. Furthermore, the barriers faced by women entrepreneurs in the developed and the developing countries are slightly different. CoPs and networking play an important role for women's learning. The chapter widens the knowledge regarding Communities of Practice and their role in helping women entrepreneurs and is an original contribution to the research field of women entrepreneurship.
IT – Offshoring and a Cross National Intra Organizational Community of Practice
Authors: Hermandrud Inge
Published: March 2016

This chapter present findings from a case study of IT-offshoring. While current research stress problems related to cultural differences and formal constrains for the development of a cross national community of practice, this chapter develops theory from the perspective of practice based theorizing. Doing so, it describes practices which promote learning across IT programmers in Norway and Vietnam. Furthermore it discusses whether or not this can be described as a community of practice and implications for management.
Case Study – Construction of Malikai's Tension Leg Platform (TLP) Hull
Authors: Abu Bakar M. B. , Roa D. T. B. , Hanafi H. M.
Published: March 2016

The construction of the Malikai Tension Leg Platform (TLP) hull involved the fabrication and assembly of sixteen (16) blocks with nodes, columns and pontoons ranging in weight from 300 MT to nearly 1,000 MT. A fabrication and assembly plan with an aggressive skyline schedule of 17-months completion was put in place together with a project-centric and dedicated production engineering to ensure all drawings were issued in line with the requirements of the schedule.

Prior to construction start-up, a mock-up involving the actual construction of one (1) block segment was planned to be carried-out to check on the constructability of the drawings and workability of allocated facilities and jig devices. The mock-up construction of one (1) node block segment which commenced in January 2013 became a barometer to determine the readiness of personnel and facilities involved including drawings and constructional devices such as the bending and welding jigs. The success of the mock-up ultimately paved the way for the April 2013 start of fabrication for the lower parts of the hull consisting of four (4) corner nodes and four (4) connecting pontoons.

With a Command Centre and a War Room for coordinating and reporting inter-actions combined with three (3) concurrent subcontractors and a workforce of over 1,000 personnel, construction work moved forward and progressed steadily up to the four (4) lower columns. And by January 2014, fabrication and assembly of the remaining four (4) upper columns were underway. Two (2) months later, integration of the hull started with the first node block being erected in place followed by the adjoining pontoons a month later. Finally by March 2015, the last upper column block was erected thereby completing the final stage of hull integration.
Students’ views on the block evaluation process: A descriptive analysis
Authors: Pakkies Ntefeleng E. , Mtshali Ntombifikile G.
Published: March 2016

Background: Higher education institutions have executed policies and practices intended to determine and promote good teaching. Students’ evaluation of the teaching and learning process is seen as one measure of evaluating quality and effectiveness of instruction and courses. Policies and procedures guiding this process are discernible in universities, but it isoften not the case for nursing colleges.Objective: To analyse and describe the views of nursing students on block evaluation, and how feedback obtained from this process was managed.Method: A quantitative descriptive study was conducted amongst nursing students (n = 177) in their second to fourth year of training from one nursing college in KwaZulu-Natal. A questionnaire was administered by the researcher and data were analysed using the Statistical Package of Social Sciences Version 19.0.Results: The response rate was 145 (81.9%). The participants perceived the aim of block evaluation as improving the quality of teaching and enhancing their experiences as students.They questioned the significance of their input as stakeholders given that they had never been consulted about the development or review of the evaluation tool, or the administration process; and they often did not receive feedback from the evaluation they participated in.Conclusion: The college management should develop a clear organisational structure with supporting policies and operational guidelines for administering the evaluation process. The administration, implementation procedures, reporting of results and follow-up mechanisms should be made transparent and communicated to all concerned. Reports and actions related to these evaluations should provide feedback into relevant courses or programmes.Keywords: Student evaluation of teaching; perceptions; undergraduate nursing students; evaluation process
Family medicine in Denmark: Are there lessons for Botswana and Africa?
Authors: Setlhare Vincent
Published: March 2016

Family medicine is a new specialty in Botswana and many African countries and its definitionand scope are still evolving. In this region, healthcare is constrained by resource limitation andinefficiencies in resource utilisation. Experiences in countries with good health indicators canhelp inform discussions on the future of family medicine in Africa. Observations made duringa visit to family physicians (FPs) in Denmark showed that the training of FPs, the practice offamily medicine and the role of support staff in a family practice were often different andsometimes unimaginable by African standards. Danish family practices were friendly andenmeshed in an egalitarian and efficient health system, which is supported by an effectiveinformation technology network. There was a lot of task shifting and nurses and clerical staffattended to simple or uncomplicated aspects of patient care whilst FPs attended to morecomplicated patient problems. Higher taxation and higher health expenditure seemed toundergird the effective health system. An egalitarian relationship amongst patients andhealthcare workers (HCW) may help improve patient care in Botswana. Task shifting shouldbe formalised, and all sectors of primary healthcare should have fast and effective informationtechnology systems. HCW training and roles should be revised. Higher health expenditure isnecessary to achieve good health indicators.Keywords: task shifting, Family Medicine, Family Physician, Denmark, health expenditure, egalitarian
Opschorting overwinnen
Authors: Bellis Delphine
Published: March 2016

Overcoming the Suspension of Assent: The Academic Roots of Gassendi’s Probabilism

In this paper, I show that, beyond the role played by Pyrrhonian arguments in rebuking Aristotelian theses, Academic philosophy offered to Gassendi a probabilist model of knowledge which, contrary to the Pyrrhonian suspension of assent, opened the possibility of a natural philosophy conceived as a science of appearances. In addition to Gassendi’s erudite interest for Cicero and Charron, Academic probabilism suited Gassendi’s own practice as a natural philosopher in the realms of meteorology and astronomy. But first and foremost, Gassendi’s preference for Academic philosophy rather than for Pyrrhonism was motivated, early in his philosophical career, by ethical concerns immanent to his practice of savant: the importance of preserving his libertas philosophandi for his experimental approach to nature, combined with his personal incapacity not to incline toward one opinion or another, led him to formulate his epistemological probabilism and to claim the freedom to revise his opinions from day to day.
De opschorting van het oordeel
Authors: Wieland Jan Willem
Published: March 2016

Suspension of Judgment

What does it take to suspend one’s judgment? In this introduction to the special issue ‘Scepticism and the suspension of judgment’, I present a conceptual analysis of suspension of judgment (what it is, what it isn’t, and why we might want to do it). Basically I argue that suspension is a mental attitude of neutrality. If you suspend judgment on a certain proposition, you are neutral towards its truth. In addition, I make a few suggestions on how to further analyse this attitude of neutrality, and distinguish it from other attitudes such as doubt and inquisitiveness.
Flux measurements by the NRC Twin Otter atmospheric research aircraft: 1987–2011
Authors: Desjardins Raymond L. , Worth Devon E. , MacPherson J. Ian , Bastian Matthew , Srinivasan Ramesh
Published: March 2016

Abstract. Over the past 30 years, the Canadian Twin Otter research group has operated an aircraft platform for the study of atmospheric greenhouse gas fluxes (carbon dioxide, ozone, nitrous oxide and methane) and energy exchange (latent and sensible heat) over a wide range of terrestrial ecosystems in North America. Some of the acquired data from these projects have now been archived at the Flight Research Laboratory and Agriculture and Agri-Food Canada. The dataset, which contains the measurements obtained in eight projects from 1987 to 2011 are now publicly available. All these projects were carried out in order to improve our understanding of the biophysical controls acting on land-surface atmosphere fluxes. Some of the projects also attempted to quantify the impacts of agroecosystems on the environment. To provide information on the data available, we briefly describe each project and some of the key findings by referring to previously published relevant work. As new flux analysis techniques are being developed, we are confident that much additional information can be extracted from this unique data set.
الطرق والاستراتيجيات التي اتبعها المكتبيون العمانيون لمعالجة أرتفاع أسعار مصادر المعلومات الإلكترونية
Authors: Al Harrasi Nabhan
Published: March 2016

الطرق والاستراتيجيات التي اتبعها المكتبيون العمانيون لمعالجة أرتفاع أسعار مصادر المعلومات الإلكترونية

في دراستين منفصلتين قـام بهما Bosch و Henderson في عامــي 2011 و 2012 لصـالح مـؤسسة Ebsco تـبين مـن نتائـج إحـداهما ارتفاعـا سنـويا في اسـعار الاشــتراكات في الـدوريات العلمية بشكـل عـام ودوريـات العلـوم البحـتة و التطبيقيـة بشكـل خـاص وفي مقـدمتها دوريات الكيمياء والفيـزياء. كما أظهـرت أن السـوق العالمي للدوريات الإلكترونية شهـد ارتفاعا في أسعـار الـدوريات حيث ارتفعت بمعدل 6 % في العـام 2012 وتوقعـت الـدراسة في نتائجها أن تـرتفع الأسعـار بنسبة 7 % في العـام 2013 (Bosch and Henderson, 2012) في ظـل هـذا الارتفـاع المتنـامـي، أظهـرت الدراسة الأخرى بأن 34% من 450 مكـتبة أكـاديمية على مستـوى العـالم شملها الاستقصاء واجهــت تخفــيض بنســب مختلفــة في ميزانيتها للعـام 2011 (Bosch, Henderson and Klusendorf, 2011). دراسـة Weir 2010)) تبين أن متـوسط أسعـار الاشتراك بـدوريات العلـوم والهندسـة في جـامعة State Murray بالولايـات المتحدة ارتفـع سبـع مـرات عـن أسعـار المصـادر في دوريـات العلـوم الإنسـانية. توضـح الـدراسة بأن معـدل الارتفـاع السنـوي في دوريـات العـلوم لا يتجـاوز 9% سنـويا فيما يصـل في دوريـات الانسـانيات إلى 5%.
المكتبات الاكاديمية العمانية وبعد دخولها البيئة الرقمية والاشتراك في مجموعة من قواعد البيانات الإلكترونية وفقاً لإمكاناتها المادية والتقنية، تأثرت، كحال المكتبات الأخرى، بارتفاع أسعار مصادر المعلومات الإلكترونية. هذا التحدي كان مفصلياً وله أبعاد كثيرة على الاستمرار في التميز في تقديم الخدمات والثبات، إذا لم يكن التنامي، في الاشتراك في مصادر المعلومات الإلكترونية.
وعليه، فالهدف الرئيسي للدراسة المقترحة هو التعرف على الخطط والاستراتيجيات التي أتبعها القائمين على المكتبات الاكاديمية العمانية في تقليل آثار ارتفاع مصادر المعلومات الإلكترونية. وكنتيجة يمكن النظر في تجارب عالمية أخرى أدرجتها الدراسات السابقة للنظر في مدى تشابه واختلاف نمط التفكير وأسلوب المعالجة لهذه القضية. وهنا تكمن أهمية الدراسة كونها تحلل بعمق مدى قدرة مدراء المكتبات الاكاديمية العمانية في إيجاد بدائل تتوافق من جهة مع رغبتهم ورغبة المستفيدين من مكتباتهم في توفير مصادر معلومات إلكترونية عالية المستوى، ومن جهة أخرى، التوافق مع الميزانية المحدودة والاستمرار المتزايد في أسعار مصادر المعلومات الإلكترونية.
الهدف سابق الذكر، وما سيندرج بعده من أهداف فرعية، لا يمكن تحقيقه إلا بالحوار المباشر مع مدراء المكتبات ورؤساء الأقسام ذات العلاقة. وعليه، ستستخدم الدراسة المقترحة المنهج الوصفي النوعي القائم على المقابلات الشخصية المركزة والحوار المتبادل الذي يمكن من خلاله التعرف على اختلاف الخطط والاستراتيجيات التي تتبعها كل مكتبة ومدى فعاليتها ونتائجها. ستحلل هذه المقابلات وفقاً لطريقة "التحليل الموضوعي" المعتمدة على تحليل المقابلات وفقاً لمحاور موضوعية رئيسية وأخرى فرعية، وفي كل محور توضح أوجه التشابه والاختلاف بين المكتبات.