bluuebunny/crossref_metadata_2025 huggingface dataset:
Infrared Absorption Characteristics Analysis for Square Loop Nanostructure of Al Substrate
Authors: Pan Qinghui , Wang Qizhen , Shuai Yong , Tan Heping
Published: March 2016

We present a 2D square loop-shaped nanostructure, which is made of a square loop aluminum array on Al2O3 spacer and Al substrate. High absorption peaks are obtained at 3.5μm and 9μm when the incident wave is vertically. In the design of dual-band or multi-band structure, the two high absorption bands are designed to stimulate the outer magnetic excitation of the first-order and the high-order magnetic resonance wavelength. For structure design with two absorption peaks or multiple absorption peaks, the expectation bands with high absorption would be obtained in the cooperation between first-order and higher-order magnetic resonance due to the outer structure. The main absorption peak due to the inner structure may be coupled the second absorption peak due to the outer structure. Then the absorption bandwidth could be broadened and the dual-band perfect absorption effect could be obtained in this loop-shaped structure.
Investigation of Mechanism for a Thermal Cloak Metamaterial by an Entropy Production Approach
Authors: Zhang H.-C. , Yu H.-Y. , Li Y. , Song N.-Q. , Wei Y.-Q.
Published: March 2016

With the development of metamaterials, microscale thermal cloak attracted many researchers’ attention. It was found that a thermodynamic cloak has unique characteristics of heat transfer transformation, with fundamental principle of transformation optics applied in thermodynamic field. An overview of thermal cloak related studies have not explained the physical mechanism in view of energy aspect. In the current work, two-dimensional heat transfer model of a multilayer thermal cloak was investigated through simulation according to Schittny’s microstructured model as well as an only polydimethylsiloxane protected layer model and plate model as control groups. Numerical simulations were developed with ANSYS FLUENT software for three models respectively in the process of heating to analysis the heat transfer and stealth protection during transient heat transfer process. The simulation results were agreed well with other’s previous experiment results on temperature distribution. The cloaking mechanism was analyzed by entropy generation approaches, and deriving the thermodynamics explanation at the aspect of the energy transfer. Thermodynamic cloak structure has a good heat stealth effect on the process of heat transfer, without the effecting outside the protected object on the distribution of both temperature and energy. Thermodynamic cloak control the energy dissipation inside the multi-layer structure, but the maximum dissipation position was shifted along the heat transfer processing.
Computational Investigation of Graphene Behavior Under Differential Water Pressure and Possible Mass Transfer Influences
Authors: Jafari Somaye , Darbandi Masoud , Saidi Mohammad Said
Published: March 2016

Because of its unique properties, graphene has attracted the attentions of many academic research groups and recently, the industry. One of the promising applications of the graphene is in micro/nano-sensors, e.g. using it as a pressure sensor. To use it in mechanical-based nano-sensors, it is very important to investigate the mechanical behavior of the nano-sized graphene sheet and its sensitivity to the medium changes applied on its faces. In this work, we use the molecular dynamics MD method and simulate the behavior of graphene sheet under differential water pressure influences. In this regard, a square straight monolayer graphene sheet is placed as a separator diaphragm between two different water boxes having different pressure/density magnitudes. The graphene atoms located on four sides around the graphene sheet are fixed during the simulations. At first, the two water boxes are in the same condition, i.e., they are a copy of each other. Next, the density of one of the water boxes is changed abruptly to impose the desired pressure difference. We also investigate the mass transfer through the imposed graphene sheet and its impact on the achieved graphene sheet behavior in this study. To the authors’ knowledge, this is the first study to investigate the graphene behavior in this manner. Indeed, one objective of this work is to find the sensitivity of nanoscale graphene sheet to low and high pressure/density differences by investigating its deflections.
A Microstructure-Based Monte Carlo Investigation on the Anisotropic Radiative Transfer in Porous Ceramics
Authors: Wang B. X. , Zhao C. Y.
Published: March 2016

Thermal barrier coatings provide excellent thermal insulation for metal components of gas turbines. Although the relationships between microstructures and mechanical properties as well as thermal conductivity of various TBCs have been extensively studied, there still exists a deficiency of a full understanding on microstructural-related thermal radiation transport inside them, which becomes more and more crucial for advanced gas turbine applications requiring higher operating temperatures. This study aims at presenting a microstructure-based numerical investigation on radiative transfer in the air plasma sprayed (APS) TBC.

In this study, the microstructures of APS TBCs are quantitatively reconstructed based on the Ultra-Small-Angle X-Ray Scattering (USAXS) measurement by the Stony Brook University group, in which the microscale interlamellar pores, intrasplat cracks and globular voids are regarded as oblate spheroids with different sizes and aspect ratios, with a specific distribution of orientations. This is a typical anisotropic medium, in which the physical properties vary with the observing direction. The anisotropic feature of radiative properties including the scattering coefficient and phase function is for the first time demonstrated using the discrete dipole approximation (DDA) method. A modified Monte Carlo method is proposed and implemented to solve the anisotropic radiative transfer problem in such medium. The spectral normal-hemispherical reflectance and transmittance of the coating are thus obtained and further compared with the experimental data from literature as well as our group to validate this numerical method. This work provides a versatile numerical framework for the study of the anisotropic radiative transfer mechanism in APS thermal barrier coatings based on microstructure charaterization.
Enhanced Nucleate Pool Boiling From Microstructured Surfaces Fabricated by Selective Laser Melting
Authors: Ho Jin Yao , Wong Kin Keong , Leong Kai Choong , Yang Chun
Published: March 2016

Selective laser melting (SLM) is a promising manufacturing method which enables the production of complex structured components from base metal powders. With the development of SLM, the possibility of fabricating functional heat transfer devices such as heat pipes and heat sinks using this technique has also gained significant interest in the recent years. In this paper, the possibilities of producing microstructured surfaces using SLM to promote nucleate pool boiling heat transfer were explored. The SLM facility (SLM 250 HL by SLM Solutions GmbH) at the Future of Manufacturing Laboratory 1 of Singapore Centre for 3D Printing (SC3DP) in Nanyang Technological University (NTU), Singapore was employed for the fabrication of the surfaces. The machine is comprised of a Gaussian distributed Yb:YAG laser with maximum power of 400 W and laser beam spot size of 80 μm which melts and fuses the AlSi10Mg base powder of distribution size 20 μm to 63 μm layer-by-layer to develop three-dimensional structures.

In total, four 1 cm × 1 cm microstructured surfaces were produced; namely micro-cavity surface, micro-fin surface, micro-sized rectangular channel (MRC) surface and micro-sized square channel (MSC) surface. Saturated pool boiling experiments were conducted on these surfaces in a water-cooled thermosyphon with FC-72 as the coolant fluid under atmospheric condition. In comparison with a plain surface, the MRC and MSC surfaces exhibited marginal improvements in the average heat transfer coefficient whilst more significant enhancements of up to 51.2% were demonstrated with the micro-cavity and micro-fin surfaces. At low heat fluxes (< 7 W/cm2), minimal differences in heat transfer performances between the microstructured surfaces and plain surface were observed. For increased heat fluxes, incremental enhancements in the heat transfer coefficients were observed for the micro-cavity and micro-fin surfaces as compared to the plain surface. The highest enhancement in the heat transfer coefficient over the plain surface was determined to be 63.5% for the micro-fin surface at the heat flux of 17.9 W/cm2 and it was also observed that the heat transfer coefficient of micro-fin surface is consistently higher that of other microstructured surfaces for the range of heat fluxes tested. In addition, higher critical heat fluxes were also achieved with all microstructured surfaces as compared to the plain surface with the highest CHF of 46.2 W/cm2 for the micro-fin and MRC surface. Visual observations suggest that the enhancement in heat transfer from the microstructured surfaces is likely to be due to the increased bubble nucleation sites created from the extended surfaces and the artificial cavities. In summary, these results indicate the promising use of SLM to produce surface features that will enhance pool boiling heat transfer.
Experimental Investigation on Solar Thermal Properties of Magnetic Nanofluids for Direct Absorption Solar Collector
Authors: He Qinbo , Yan Geni , Wang Shuangfeng
Published: March 2016

Nanofluids are found to have good optical and thermal properties as direct sunlight absorbers in solar collectors. In this article, Co-H2O nanofluids were prepared through two-step method. The photothermal properties of nanofluids were investigated under different magnetic field intensity. The effect of Co-H2O nanofluids on the efficiency of a direct absorption solar collector was also investigated experimentally. The experimental results show that the applied magnetic field can enhance the solar absorption ability of Co-H2O nanofluids, and has an optimal magnetic field intensity 30Gs. The highest temperature of Co-H2O nanofluid (0.04wt%, 30Gs) is increased up to 39.5% compared with deionized water. The maximum efficiency of direct absorption solar collector with Co-H2O nanofluid under 30Gs magnetic field (0.1wt%, 30nm) is increased up to 51.70% and 13.24% compared with water and Co-H2O nanofluid without magnetic field, respectively. The results indicate that the magnetic field has the potential to effectively improve the solar absorption capabilities of direct absorption solar collectors with magnetic nanofluids.
Effect of Nanoparticles on H2O/LiBr Falling Film Absorption Process
Authors: Zhang L. Y. , Li Y. , Wang Y. , Cao L. X. , Meng X. Z.
Published: March 2016

Absorber is an important component in absorption refrigerating system. Its performance plays a significant role on the overall efficiency of absorption refrigerating system. The nanofluids which can enhance the heat and mass transfer will be utilized to absorber for enhancing the water vapor absorption process and improving the absorber efficiency. The software CFD-FLUENT is used to analyze the falling film absorption process of the nanofluids, which consists of H2O/LiBr solution with Fe3O4 nanoparticles in this paper. The results indicate that the enhancing heat and mass transfer of nanofluids is related to the nanoparticle concentration and size. The stronger the nanoparticle concentration, the greater enhancement of heat and mass transfer of falling film; while the smaller the nanoparticle size, the greater enhancement of heat and mass transfer of falling film. It is also found that the enhancement ratio of heat and mass transfer flux reach 1.48 and 1.37, respectively, as the Fe3O4 nanoparticles mass concentration of 0.01wt% and the size of 50nm.
Experimental and Numerical Studies of Fluid Flow Confined in Microchannel
Authors: Wang Yan , Ling Xiang
Published: March 2016

The heat transfer performance of fluid flowing in a microchannel was experimentally studied, to meet the requirement of extremely high heat flux removal of microelectronic devices. There were 10 parallel microchannels with rectangular cross-section in the stainless steel plate, which was covered by a glass plate to observe the fluid flowing behavior, and another heating plate made of aluminum alloy was positioned behind the microchannel. Single phase heat transfer and fluid flow downstream the microchannel experiments were conducted with both deionized water and ethanol. Besides experiments, numerical models were also set up to make a comparison with experimental results.

It is found that the pressure drop increases rapidly with enlarging Reynolds number (200), especially for ethanol. With comparison, the flow resistance of pure water is smaller than ethanol. Results also show that the friction factor decreases with Reynolds number smaller than the critical value, while increases the velocity, the friction factor would like to keep little changed. We also find that the water friction factors obtained by CFD simulations in parallel microchannels are much larger than experiment results.

With heat flux added to the fluid, the heat transfer performance can be enhanced with larger Re number and the temperature rise could be weaken. Compared against ethanol, water performed much better for heat removal. However, with intensive heat flux, both water and ethanol couldn’t meet the requirement and the temperature at outlet would increase remarkably, extremely for ethanol. These findings would be helpful for thermal management design and optimization.
Growth optimization for self-catalyzed GaAs-based nanowires on metal-induced crystallized amorphous substrate
Authors: Ren Dingding , Høiaas Ida M. , Reinertsen Johannes F. , Dheeraj Dasa L. , Munshi A. Mazid , Kim Dong-Chul , Weman Helge , Fimland Bjørn-Ove
Published: March 2016

The growth of monocrystalline semiconductor nanowires on arbitrary substrates via the metal-induced crystallization (MIC) process extends the possible combinations of substrates and epitaxial active materials. However, it is still difficult to accomplish high-density vertical nanowire growth on the MIC polycrystalline Si(111) substrate. Here, the authors report on the growth of self-catalyzed GaAs nanowires by molecular beam epitaxy on MIC polycrystalline Si(111) substrates with different surface oxide conditions. Forming the surface oxide by annealing the freshly hydrofluoric acid-etched MIC polycrystalline Si(111) substrate in an ambient atmosphere is found to be a key step to grow high-density GaAs nanowires. Moreover, the addition of Sb during nanowire growth improves the density of vertical nanowires. Photoluminescence measurements reveal a high optical quality of the GaAs nanowires, indicating that the nanowires grown on MIC polycrystalline Si(111) substrate may be used as building blocks for semiconductor nanowire optoelectronic devices on arbitrary substrates.
Using a Ternary Diagram to Display a System's Evolving Energy Distribution
Authors: Brazzle Bob , Tapp Anne
Published: March 2016

A ternary diagram is a graphical representation used for systems with three components. They are familiar to mineralogists (who typically use them to categorize varieties of solid solution minerals such as feldspar) but are not yet widely used in the physics community. Last year the lead author began using ternary diagrams in his introductory (calculus-based) physics course in a novel context—tracking the distribution of energy in a system as it transforms among three categories (e.g., gravitational, kinetic, and thermal) or transfers among three objects (e.g., inductor, capacitor, and resistor). The ternary diagram has some significant advantages over other graphical representations of energy distributions: an entire scenario can appear in a single plot, even when using very small time steps. This also means that the plot can be used to compare relative rates of energy change during various processes. Our goal for this paper is to introduce the ternary diagram and discuss these advantages in hopes that this will stimulate broader use of ternary diagrams and further research into their educational utility.
A Simple Experimental Setup for Teaching Additive Colors with Arduino
Authors: Carvalho Paulo Simeão , Hahn Marcelo
Published: March 2016

The result of additive colors is always fascinating to young students. When we teach this topic to 14- to 16-year-old students, they do not usually notice we use maximum light quantities of red (R), green (G), and blue (B) to obtain yellow, magenta, and cyan colors in order to build the well-known additive color diagram of Fig. 1. But how about using different light intensities for R, G, and B? What colors do we get? This problem of color mixing has been intensively discussed for decades by several authors, as pointed out by Ruiz's “Color Addition and Subtraction Apps” work and the references included therein. An early LED demonstrator for additive color mixing dates back to 1985, and apps to illustrate color mixing are available online. In this work, we describe an experimental setup making use of a microcontroller device: the Arduino Uno. This setup is designed as a game in order to improve students' understanding of color mixing.
Locating a smartphone's accelerometer
Authors: Mau Sidney , Insulla Francesco , Pickens Elliot E. , Ding Zihao , Dudley Scott C.
Published: March 2016

While prior papers in this column addressed aspects of radial acceleration using smartphones, this paper describes a technique to locate the accelerometer in the phone to within a couple millimeters.
Physical Activity in People With Mental Illness in Hong Kong: Application of the Health Belief Model
Authors: Mo Phoenix K. H. , Chong Eddie S. K. , Mak Winnie W. S. , Wong Samuel Y. S. , Lau Joseph T. F.
Published: March 2016

Physical activity is associated with various health benefits for people with mental illness (PMI). Very few studies to date have examined the factors associated with physical activity among PMI in the Chinese context. The present study examined the factors related to physical activity using the health belief model and the association between physical activity and perceived health among 443 PMI in Hong Kong using stratified sampling. Results from the structural equation modeling showed that among all the factors of the health belief model, self-efficacy was significantly related to higher levels of physical activity, and perceived barriers were significantly related to lower levels of physical activity. In addition, physical activity was significantly related to better perceived health and fewer health needs. Interventions to promote physical activity among PMI should aim to increase their self-efficacy in initiating and adhering to physical activity and to remove barriers to physical activity.
Learning to Like Exercising: Evaluative Conditioning Changes Automatic Evaluations of Exercising and Influences Subsequent Exercising Behavior
Authors: Antoniewicz Franziska , Brand Ralf
Published: March 2016

This multistudy report used an experimental approach to alter automatic evaluations of exercise (AEE). First, we investigated the plasticity of AEE (study 1). A computerized evaluative conditioning task was developed that altered the AEE of participants in two experimental groups (acquisition of positive/negative associations involving exercising) and a control group (ηpart.2 = .11). Second, we examined connections between changes in AEE and subsequent exercise behavior (chosen intensity on a bike ergometer; study 2) in individuals that were placed in groups according to their baseline AEE. Group differences in exercise behavior were detected (ηpart.2 = .29). The effect was driven by the performance of the group with preexisting negative AEE that acquired more positive associations. This illustrates the effect of altered AEE on subsequent exercise behavior and the potential of AEE as a target for exercise intervention.
Relations Between Autonomous Motivation and Leisure-Time Physical Activity Participation: The Mediating Role of Self-Regulation Techniques
Authors: Nurmi Johanna , Hagger Martin S. , Haukkala Ari , Araújo-Soares Vera , Hankonen Nelli
Published: March 2016

This study tested the predictive validity of a multitheory process model in which the effect of autonomous motivation from self-determination theory on physical activity participation is mediated by the adoption of self-regulatory techniques based on control theory. Finnish adolescents (N = 411, aged 17–19) completed a prospective survey including validated measures of the predictors and physical activity, at baseline and after one month (N = 177). A subsample used an accelerometer to objectively measure physical activity and further validate the physical activity self-report assessment tool (n = 44). Autonomous motivation statistically significantly predicted action planning, coping planning, and self-monitoring. Coping planning and self-monitoringmediated the effect of autonomous motivation on physical activity, although self-monitoring was the most prominent. Controlled motivation had no effect on self-regulation techniques or physical activity. Developing interventions that support autonomous motivation for physical activity may foster increased engagement in self-regulation techniques and positively affect physical activity behavior.
Mouse redox histology using genetically encoded probes
Authors: Fujikawa Yuuta , Roma Leticia P. , Sobotta Mirko C. , Rose Adam J. , Diaz Mauricio Berriel , Locatelli Giuseppe , Breckwoldt Michael O. , Misgeld Thomas , Kerschensteiner Martin , Herzig Stephan , Müller-Decker Karin , Dick Tobias P.
Published: March 2016

A cryogenic chemical processing method maps the redox state at the cellular and subcellular level in tissue sections.
Propensity Score Analysis of the Role of Initial Antifungal Therapy in the Outcome of Candida glabrata Bloodstream Infections
Authors: Puig-Asensio M. , Fernández-Ruiz M. , Aguado J. M. , Merino P. , Lora-Pablos D. , Guinea J. , Martín-Dávila P. , Cuenca-Estrella M. , Almirante B.
Published: March 2016

Candida glabrata
isolates have reduced
in vitro
susceptibility to azoles, which raises concerns about the clinical effectiveness of fluconazole for treating bloodstream infection (BSI) by this
Candida
species. We aimed to evaluate whether the choice of initial antifungal treatment (fluconazole versus echinocandins or liposomal amphotericin B [L-AmB]-based regimens) has an impact on the outcome of
C. glabrata
BSI. We analyzed data from a prospective, multicenter, population-based surveillance program on candidemia conducted in 5 metropolitan areas of Spain (May 2010 to April 2011). Adult patients with an episode of
C. glabrata
BSI were included. The main outcomes were 14-day mortality and treatment failure (14-day mortality and/or persistent
C. glabrata
BSI for ≥48 h despite antifungal initiation). The impact of using fluconazole as initial antifungal treatment on the patients' prognosis was assessed by logistic regression analysis with the addition of a propensity score approach. A total of 94 patients with
C. glabrata
BSI were identified. Of these, 34 had received fluconazole and 35 had received an echinocandin/L-AmB-based regimen. Patients in the echinocandin/L-AmB group had poorer baseline clinical status than did those in the fluconazole group. Patients in the fluconazole group were more frequently (55.9% versus 28.6%) and much earlier (median time, 3 versus 7 days) switched to another antifungal regimen. Overall, 14-day mortality was 13% (9/69) and treatment failure 34.8% (24/69), with no significant differences between the groups. On multivariate analysis, after adjusting for baseline characteristics by propensity score, fluconazole use was not associated with an unfavorable evolution (adjusted odds ratio [OR] for 14-day mortality, 1.16, with 95% confidence interval [CI] of 0.22 to 6.17; adjusted OR for treatment failure, 0.83, with 95% CI of 0.27 to 2.61). In conclusion, initial fluconazole treatment was not associated with a poorer outcome than that obtained with echinocandins/L-AmB regimens in patients with
C. glabrata
BSI. (This study has been registered at ClinicalTrials.gov under registration no. NCT01236261.)
Characterization of an IncA/C Multidrug Resistance Plasmid in Vibrio alginolyticus
Authors: Ye Lianwei , Li Ruichao , Lin Dachuan , Zhou Yuanjie , Fu Aisi , Ding Qiong , Chan Edward Wai Chi , Yao Wen , Chen Sheng
Published: March 2016

Cephalosporin-resistant
Vibrio alginolyticus
was first isolated from food products, with β-lactamases encoded by
bla
PER-1
,
bla
VEB-1
, and
bla
CMY-2
being the major mechanisms mediating their cephalosporin resistance. The complete sequence of a multidrug resistance plasmid, pVAS3-1, harboring the
bla
CMY-2
and
qnrVC4
genes was decoded in this study. Its backbone exhibited genetic homology to known IncA/C plasmids recoverable from members of the family
Enterobacteriaceae
, suggesting its possible origin in
Enterobacteriaceae
.
Urinary Concentrations and Antibacterial Activity of BAL30072, a Novel Siderophore Monosulfactam, against Uropathogens after Intravenous Administration in Healthy Subjects
Authors: Straubinger Marion , Blenk Holger , Naber Kurt G. , Wagenlehner Florian M. E.
Published: March 2016

This annex study to a phase 1 study aimed to correlate urinary concentrations and bactericidal titers (UBTs) of BAL30072, a novel siderophore monosulfactam, in healthy subjects in order to evaluate which dosage of BAL30072 should be investigated in a clinical study on complicated urinary tract infection (UTI). Three cohorts of a total of 19 healthy male subjects were included in the add-on study and received the following BAL30072 dosages. The 1st cohort received 1 g once a day (q.d.) intravenously (i.v.) (1 h) on day 1 and 1 g thrice daily (t.i.d.) on day 2, the 2nd cohort received 2 g q.d. i.v. (1 h) on day 1 and 2 g t.i.d. on day 2, and the 3rd cohort received 1 g q.d. i.v. (4-h infusion) on day 8. Urine was collected up to 24 h after drug administration. UBTs were determined for seven
Escherichia coli
isolates (three wild type [WT], CTX-M-15, TEM-3, TEM-5, NDM-1), two
Klebsiella pneumoniae
isolates (WT, KPC), one
Proteus mirabilis
isolate (WT), and two
Pseudomonas aeruginosa
isolates (WT, VIM-1 plus AmpC). Urine drug concentrations were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The median urinary excretions of BAL30072 ranged between 38% and 46% (3 cohorts). The median UBTs after i.v. administration of 1 or 2 g q.d. and after 1 or 2 g t.i.d. showed positive UBTs for 24 h after the lowest dosage (1 g q.d.) for 5 of 7 of the
Enterobacteriaceae
strains and after the higher dosage of 2 g administered i.v. t.i.d. for all strains tested. After i.v. infusion of 1 g over 4 h, positive UBTs were demonstrated for three
E. coli
strains for up to 12 h, for the
K. pneumoniae
(KPC) strain for up to 8 h, and for the
P. aeruginosa
(VIM-1 plus AmpC) strain for up to only 4 h. The minimal bactericidal concentrations (MBCs) of the
E. coli
(NDM-1) strain and the
K. pneumoniae
(WT) strain correlated well between broth and urine but did not correlate well for the two
P. aeruginosa
strains. BAL30072 exhibits positive UBTs for 24 h even after a dosage of 1 g administered i.v. q.d. for 5 of 7
Enterobacteriaceae
strains and after 2 g administered i.v. t.i.d. for all strains except one
P. aeruginosa
strain (50% of the time). In general, the UBTs correlated well with the MICs of the
Enterobacteriaceae
but were lower for
P. aeruginosa
. The clinical efficacy with a dosage regimen of BAL30072 of 2 g administered i.v. t.i.d. should be evaluated in the treatment of complicated UTI.
Characterization of 22 Antituberculosis Drugs for Inhibitory Interaction Potential on Organic Anionic Transporter Polypeptide (OATP)-Mediated Uptake
Authors: Parvez M. Masud , Jung Jin Ah , Shin Ho Jung , Kim Dong Hyun , Shin Jae-Gook
Published: March 2016

We investigated the inhibitory interaction potential of 22 currently marketed antituberculosis (TB) drugs on organic anion-transporting polypeptide 1B1 (OATP1B1)-, OATP2B1-, and OATP1B3-mediated uptake using
in vitro
Xenopus
oocytes and HEK cells. Rifabutin, ethambutol, amoxicillin, linezolid,
p
-amino salicylic acid, and rifapentine exhibited mild to moderate inhibitory effects on OATP-mediated uptake of estrone-3 sulfate, estradiol 17β-
d
-glucuronide, and rosuvastatin. The 50% inhibitory concentration (IC
50
) values of rifabutin, amoxicillin, ethambutol,
p
-amino salicylic acid, and linezolid were 35.4, 36.2, 57.6, 72.6, and 65.9 μM, respectively, for uptake mediated by organic anionic transporter polypeptide 1B1 (OATP1B1) and 28.8, 28.9, 53.9, 31.5, and 61.0 μM, respectively, for uptake mediated by organic anionic transporter polypeptide 1B3 (OATP1B3). Streptomycin and linezolid showed greater inhibition of organic anionic transporter polypeptide 2B1 (OATP2B1)-mediated uptake, with IC
50
values of 33.2 and 35.6 μM, respectively, along with mild inhibition of other drugs. Furthermore, rifabutin, amoxicillin, and rifapentine significantly inhibited OATP1B1-mediated rosuvastatin uptake, with IC
50
values of 12.3, 13.0, and 11.0 μM, respectively, which showed a similar profile to estrone-3 sulfate uptake. The calculated
R
values ([
I
]

u inlet,max

/

K
i

, where [
I
]

u inlet,max

represents the maximum estimated inhibitor concentration inlet to the liver and

K
i

is the inhibition constant) as the drug-drug interaction (DDI) indexes of PAS, ethambutol, and amoxicillin were 26.1, 6.5, and 4.3 for OATP1B1 and 52.0, 8.0, and 4.6 for OATP1B3, and those for streptomycin, amikacin, and linezolid were 5.0, 4.2, and 4.4 for OATP2B1, respectively, suggesting a higher possibility of
in vivo
DDIs. This study is the first comprehensive report to show the novel inhibitory potential of 22 marketed anti-TB drugs on OATP-mediated uptake, providing evidence for future
in vivo
clinical DDI studies.
In Vitro
Activity of Delafloxacin against Clinical Neisseria gonorrhoeae Isolates and Selection of Gonococcal Delafloxacin Resistance
Authors: Soge Olusegun O. , Salipante Stephen J. , No David , Duffy Erin , Roberts Marilyn C.
Published: March 2016

We evaluated the
in vitro
activity of delafloxacin against a panel of 117
Neisseria gonorrhoeae
strains, including 110 clinical isolates collected from 2012 to 2015 and seven reference strains, compared with the activities of seven antimicrobials currently or previously recommended for treatment of gonorrhea. We examined the potential for delafloxacin to select for resistant mutants in ciprofloxacin-susceptible and ciprofloxacin-resistant
N. gonorrhoeae
. We characterized mutations in the
gyrA
,
gyrB
,
parC
, and
parE
genes and the multidrug-resistant efflux pumps (MtrC-MtrD-MtrE and NorM) by PCR and sequencing and by whole-genome sequencing. The MIC
50
, MIC
90
, and MIC ranges of delafloxacin were 0.06 μg/ml, 0.125 μg/ml, and ≤0.001 to 0.25 μg/ml, respectively. The frequency of spontaneous mutation ranged from 10
−7
to <10
−9
. The multistep delafloxacin resistance selection of 30 daily passages resulted in stable resistant mutants. There was no obvious cross-resistance to nonfluoroquinolone comparator antimicrobials. A mutant with reduced susceptibility to ciprofloxacin (MIC, 0.25 μg/ml) obtained from the ciprofloxacin-susceptible parental strain had a novel Ser91Tyr alteration in the
gyrA
gene. We also identified new mutations in the
gyrA
and/or
parC
and
parE
genes and the multidrug-resistant efflux pumps (MtrC-MtrD-MtrE and NorM) of two mutant strains with elevated delafloxacin MICs of 1 μg/ml. Although delafloxacin exhibited potent
in vitro
activity against
N. gonorrhoeae
isolates and reference strains with diverse antimicrobial resistance profiles and demonstrated a low tendency to select for spontaneous mutants, it is important to establish the correlation between these excellent
in vitro
data and treatment outcomes through appropriate randomized controlled clinical trials.
Persisting Rickettsia typhi Causes Fatal Central Nervous System Inflammation
Authors: Osterloh Anke , Papp Stefanie , Moderzynski Kristin , Kuehl Svenja , Richardt Ulricke , Fleischer Bernhard
Published: March 2016

Rickettsioses are emerging febrile diseases caused by obligate intracellular bacteria belonging to the familyRickettsiaceae. Rickettsia typhibelongs to the typhus group (TG) of this family and is the causative agent of endemic typhus, a disease that can be fatal. In the present study, we analyzed the course ofR. typhiinfection in C57BL/6 RAG1−/−mice. Although these mice lack adaptive immunity, they developed only mild and temporary symptoms of disease and survivedR. typhiinfection for a long period of time. To our surprise, 3 to 4 months after infection, C57BL/6 RAG1−/−mice suddenly developed lethal neurological disorders. Analysis of these mice at the time of death revealed high bacterial loads, predominantly in the brain. This was accompanied by a massive expansion of microglia and by neuronal cell death. Furthermore, high numbers of infiltrating CD11b+macrophages were detectable in the brain. In contrast to the microglia, these cells harboredR. typhiand showed an inflammatory phenotype, as indicated by inducible nitric oxide synthase (iNOS) expression, which was not observed in the periphery. Having shown thatR. typhipersists in immunocompromised mice, we finally asked whether the bacteria are also able to persist in resistant C57BL/6 and BALB/c wild-type mice. Indeed,R. typhicould be recultivated from lung, spleen, and brain tissues from both strains even up to 1 year after infection. This is the first report demonstrating persistence and reappearance ofR. typhi, mainly restricted to the central nervous system in immunocompromised mice.
The Cryptosporidium parvum C-Type Lectin CpClec Mediates Infection of Intestinal Epithelial Cells via Interactions with Sulfated Proteoglycans
Authors: Ludington Jacob G. , Ward Honorine D.
Published: March 2016

The apicomplexan parasite
Cryptosporidium
causes significant diarrheal disease worldwide. Effective anticryptosporidial agents are lacking, in part because the molecular mechanisms underlying
Cryptosporidium
-host cell interactions are poorly understood. Previously, we identified and characterized a novel
Cryptosporidium parvum
C-type lectin domain-containing mucin-like glycoprotein, CpClec. In this study, we evaluated the mechanisms underlying interactions of CpClec with intestinal epithelial cells by using an Fc-tagged recombinant protein. CpClec-Fc displayed Ca
2+
-dependent, saturable binding to HCT-8 and Caco-2 cells and competitively inhibited
C. parvum
attachment to and infection of HCT-8 cells. Binding of CpClec-Fc was specifically inhibited by sulfated glycosaminoglycans, particularly heparin and heparan sulfate. Binding was reduced after the removal of heparan sulfate and following the inhibition of glycosaminoglycan synthesis or sulfation in HCT-8 cells. Like CpClec-Fc binding,
C. parvum
attachment to and infection of HCT-8 cells were inhibited by glycosaminoglycans and were reduced after heparan sulfate removal or inhibition of glycosaminoglycan synthesis or sulfation. Lastly, CpClec-Fc binding and
C. parvum
sporozoite attachment were significantly decreased in CHO cell mutants defective in glycosaminoglycan synthesis. Together, these results indicate that CpClec is a novel C-type lectin that mediates
C. parvum
attachment and infection via Ca
2+
-dependent binding to sulfated proteoglycans on intestinal epithelial cells.
Insight into the Dual Functions of Bacterial Enhancer-Binding Protein Rrp2 of Borrelia burgdorferi
Authors: Yin Yanping , Yang Youyun , Xiang Xuwu , Wang Qian , Yang Zhang-Nv , Blevins Jon , Lou Yongliang , Yang X. Frank
Published: March 2016

It is well established that the RpoN-RpoS sigma factor (σ
54
-σ
S
) cascade plays an essential role in differential gene expression during the enzootic cycle of
Borrelia burgdorferi
, the causative agent of Lyme disease. The RpoN-RpoS pathway is activated by the response regulator/σ
54
-dependent activator (also called bacterial enhancer-binding protein [bEBP]) Rrp2. One unique feature of Rrp2 is that this activator is essential for cell replication, whereas RpoN-RpoS is dispensable for bacterial growth. How Rrp2 controls cell replication, a function that is independent of RpoN-RpoS, remains to be elucidated. In this study, by generating a series of conditional
rrp2
mutant strains, we demonstrated that the N-terminal receiver domain of Rrp2 is required for spirochetal growth. Furthermore, a D52A point mutation at the phosphorylation site within the N terminus of Rrp2 abolished cell replication. Mutation of the ATPase motif within the central domain of Rrp2 did not affect spirochetal replication, indicating that phosphorylation-dependent ATPase activity of Rrp2 for σ
54
activation is not required for cell growth. However, deletion of the C-terminal domain or a 16-amino-acid truncation of the helix-turn-helix (HTH) DNA-binding motif within the C-terminal domain of Rrp2 abolished spirochetal replication. It was shown that constitutive expression of
rpoS
is deleterious to borrelial growth. We showed that the essential nature of Rrp2 is not due to an effect on
rpoS
. These data suggest that phosphorylation-dependent oligomerization and DNA binding of Rrp2 likely function as a repressor, independently of the activation of σ
54
, controlling an essential step of cell replication in
B. burgdorferi
.

IMPORTANCE
Bacterial enhancer-binding proteins (bEBPs) are a unique group of transcriptional activators specifically required for σ
54
-dependent gene transcription. This work demonstrates that the
B. burgdorferi
bEBP, Rrp2, has an additional function that is independent of σ
54
, that of its essentiality for spirochetal growth, and such a function is dependent on its N-terminal signal domain and C-terminal DNA-binding domain. These findings expand our knowledge on bEBP and provide a foundation to further study the underlying mechanism of this new function of bEBP.
Open-source hardware for medical devices
Authors: Niezen Gerrit , Eslambolchilar Parisa , Thimbleby Harold
Published: March 2016

Open-source hardware is hardware whose design is made publicly available so anyone can study, modify, distribute, make and sell the design or the hardware based on that design. Some open-source hardware projects can potentially be used as active medical devices. The open-source approach offers a unique combination of advantages, including reducing costs and faster innovation. This article compares 10 of open-source healthcare projects in terms of how easy it is to obtain the required components and build the device.
Climate-sensitive site index models for Norway
Authors: Antón-Fernández Clara , Mola-Yudego Blas , Dalsgaard Lise , Astrup Rasmus
Published: March 2016

The present study aims to develop biologically sound and parsimonious site index models for Norway to predict changes in site index (SI) under different climatic conditions. The models are constructed using data from the Norwegian National Forest Inventory and climate data from the Norwegian meteorological institute. Site index was modeled using the potential modifier functional form, with a potential component (POT) depending on site quality classes and two modifier components (MOD): temperature and moisture. Each of these modifiers was based on a portfolio of candidate variables. The best model for spruce-dominated stands included temperature as modifier (R2= 0.56). In the case of pine- and deciduous-dominated stands, the best models included both modifiers (R2= 0.40 and 0.54 for temperature and moisture, respectively). We illustrate the use of the models by analyzing the possible shift in SI for year 2100 under one (RCP4.5) of the benchmark scenarios adopted by the Intergovernmental Panel on Climate Change for its fifth assessment report. The models presented can be valuable for evaluating the effect of climate change scenarios in Norwegian forests.
Genome-wide analysis for identification of adaptive diversification between hepatitis C virus subtypes 1a and 1b
Authors: Li Yan , Wang Ruirui , Du Xiaogang , Zhang Mingwang , Xie Meng
Published: March 2016

Hepatitis C virus (HCV) is a major cause of liver disease and has been estimated to infect approximately 2%–3% of the world’s population. HCV genotype 1 is the subject of intense research and clinical investigations because of its worldwide prevalence and poor access to treatment for patients in developing countries and marginalized populations. The predominant subtypes 1a and 1b of HCV genotype 1 present considerable differences in epidemiological features. However, the genetic signature underlying such phenotypic functional divergence is still an open question. Here, we performed a genome-wide evolutionary study on HCV subtypes 1a and 1b. The results show that adaptive selection has driven the diversification between these subtypes. Furthermore, the major adaptive divergence-related changes have occurred on proteins E1, NS4B, NS5A, and NS5B. Structurally, a number of adaptively selected sites cluster in functional regions potentially relevant to (i) membrane attachment and (ii) the interactions with viral and host cell factors and the genome template. These results might provide helpful hints about the molecular determinants of epidemiological divergence between HCV 1a and 1b.
Skoda division of line bundle sections and pseudo-division
Authors: Kim Dano
Published: March 2016

We first present a Skoda-type division theorem for holomorphic sections of line bundles on a projective variety which is essentially the most general, compared to previous ones. Then we revisit Geometric Effective Nullstellensatz and observe that even this general Skoda division is far from sufficient to yield stronger GEN such as ‘vanishing order [Formula: see text] division’, which could be used for finite generation of section rings by the basic finite generation lemma. To resolve this problem, we develop a notion of pseudo-division and show that it can replace the usual division in the finite generation lemma. We also give a vanishing order 1 pseudo-division result when the line bundle is ample.
Analytical investigation on the minimum traffic delay at a two-phase intersection considering the dynamical evolution process of queues
Authors: Zhang Hong-Ze , Jiang Rui , Hu Mao-Bin , Jia Bin
Published: March 2016

This paper has studied the minimum traffic delay at a two-phase intersection, taking into account the dynamical evolution process of queues. The feature of delay function has been studied, which indicates that the minimum traffic delay must be achieved when at least one of the two constraint inequalities take the equal sign. We have derived the minimum delay as well as the corresponding traffic signal period, which shows that two situations are classified. Under certain circumstance, extra green time is needed for one phase while otherwise extra green time should be assigned to neither phase. Our work indicates that although the clearing policies were shown in many experiments to be optimal at isolated intersections, it is sometimes not the case.
Numerical solution of the Rosenau-KdV-RLW equation by using RBFs collocation method
Authors: Korkmaz Bahar , Dereli Yilmaz
Published: March 2016

In this study, a meshfree method based on the collocation with radial basis functions (RBFs) is proposed to solve numerically an initial-boundary value problem of Rosenau-KdV-regularized long-wave (RLW) equation. Numerical values of invariants of the motion are computed to examine the fundamental conservative properties of the equation. Computational experiments for the simulation of solitary waves examine the accuracy of the scheme in terms of error norms [Formula: see text] and [Formula: see text]. Linear stability analysis is investigated to determine whether the present method is stable or unstable. The scheme gives unconditionally stable, and second-order convergent. The obtained results are compared with analytical solution and some other earlier works in the literature. The presented results indicate the accuracy and efficiency of the method.
Selectively Fine-Tuning Bayesian Network Learning Algorithm
Authors: Alhussan Amel , El Hindi Khalil
Published: March 2016

In this work, we propose a Selective Fine-Tuning algorithm for Bayesian Networks (SFTBN). The aim is to enhance the accuracy of Bayesian Network (BN) classifiers by finding better estimations for the probability terms used by the classifiers. The algorithm augments a BN learning algorithm with a fine-tuning stage that aims to more accurately estimate the probability terms used by the BN. If the value of a probability term causes a misclassification of a training instances and falls outside its valid range then we update (fine-tune) that value. The amount of such an update is proportional to the distance between the value and its valid range. We use the algorithm to fine-tune several forms of BNs: the Naive Bayes (NB), Tree Augmented Naive Bayes (TAN), and Bayesian Augmented Naive Bayes (BAN) models. Our empirical experiments indicate that the SFTBN algorithm improves the classification accuracy of BN classifiers. We also generalized the original fine-tuning algorithm of Naive Bayesian (FTNB) for BN models. We empirically compare the two algorithms, and the empirical results show that while FTNB is more accurate than SFTBN for fine-tuning NB classifiers, SFTBN is more accurate for fine-tuning BNs than the adapted version of FTNB.
Stability of contact discontinuity for the two-species Vlasov–Poisson–Boltzmann system
Authors: Huang Lirong , Liu Shuangqian
Published: March 2016

This paper is devoted to the study of the nonlinear stability of contact wave for the Vlasov–Poisson–Boltzmann system with two-species. Based on the quasi-neutral Euler system in Lagrangian coordinates, we first construct a nontrivial profile: a local bi-Maxwellian whose parameters are also called “viscous contact wave” in the sense of hydrodynamics, then we prove that such a nontrivial profile is time-asymptotically stable by a refined energy method. For the proof, the good structure of the macroscopic equations is fruitfully exploited to attain the dissipation of the specific volumes and the electric potential, moreover, both of Lagrangian and Eulerian coordinates transformation are alternatively utilized in order to capture the higher-order energy of the electric potential.
Application and Simulation Study of Stress-Dependent Weibull Lifetime Models
Authors: Juskowiak Jochen , Bertsche Bernd
Published: March 2016

Different Weibull lifetime models are presented whose scale, shape and minimum lifetime parameters are stress-dependent. This allows describing and predicting the lifetime of products with a Weibull distribution more accurately wherever stress-dependence applies to the failure mechanism. For instance, this is the case for failures due to fatigue, on which this paper focusses. The proposed procedure encompasses a two-step maximum likelihood estimation and a Fisher matrix (FM) confidence bounds calculation, followed by a model evaluation. This model evaluation is conducted by means of a general plausibility check (PC), likelihood ratio test (LRT) and Bayesian information criterion (BIC). Their applicability to accelerated life test data is discussed and validated using test data. Finally, a simulation study confirms a wide range of applicability.