bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical and Experimental Analysis of Increasing Pressure During Pool-Boiling
Authors: Dahariya Smreeti , Betz Amy Rachel
Published: August 2018

The thermo-fluid properties of water change at high pressure. The performance of high pressure pool boiling greater than 50 Psi has not been studied widely. The aim of this paper is to analyze the experimental data to describe the effect of increasing pressure during pool boiling. Hsu’s correlation was used to predict the active nucleation sites. The maximum and minimum radii of the active nucleation sites were determined as a function of heat flux or degree of wall superheats over a wide range of pressures. The bubble dynamics are discussed using the predicted values of fundamental boiling quantities such as bubble departure diameter, active nucleation site density and bubble release frequency. The thickness of the boundary layer was assumed to be 30 microns. Rohsenow’s and Forster’s correlations were used to predict the pool boiling curve for different pressures. The comparison was made with the experimental data for water of a plain copper surface of increasing pressure. The parametric trend provides fundamental insight and explains how the system pressure can maximize the boiling efficiency of new generation boilers.
Experimental Study of Nucleate Flow Boiling to Convective Flow Boiling Transition in a Horizontal Heated Pipe
Authors: Dorao Carlos A. , Morin Flavie , Fernandino Maria
Published: August 2018

In flow boiling, two different mechanisms, namely nucleate boiling and convective boiling, are considered to be dominant at different working conditions while superimposing in a transition regime. The transition between these two regimes has been considered in different ways in available correlations in the literature. However, few experimental studies have focused on the characteristics of such transition. In this work the nucleate flow boiling-convective flow boiling transition is studied experimentally in a horizontal heated pipe of 5mm ID using R134a as working fluid. The study consist on varying the local hat flux while maintaining the mass flux, pressure and local quality fixed. It is shown that the transition is quite sharp indicating that the superimposing of both mechanism is rather limited.
Improving Liquid Supply Pathways on Graphene Oxide Coated Surfaces for Enhanced Pool Boiling Heat Transfer Performance
Authors: Rishi Aniket M. , Gupta Anju , Kandlikar Satish G.
Published: August 2018

Graphene is a two-dimensional material that possesses excellent thermal properties and thus has gained an enormous attention in the applications of heat transfer. In this work, we demonstrate the enhancement of boiling heat transfer performance on substrate coated with graphene oxide and/or copper composites. The graphene oxide and/or copper composites were introduced on the substrate by two commonly used coating techniques-dip-coating and a two-step electrochemical deposition method. The focus of this paper is to compare the morphologies, surface properties such as wickability and porosity rendered by these coating methods and compare the resultant heat transfer coefficients and critical heat fluxes. The surfaces were characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR) techniques. Critical Heat Flux of 220 W/cm2 at the wall superheat of 14.8°C was achieved for the highest 2.5% GO-Cu electrodeposited chip, while CHF of 128 W/cm2 at the wall superheat of 13.2°C was achieved for the 5 minutes dip coated test surface.
Mechanisms Underlying Foam-Based Electronucleation of Hydrates
Authors: Acharya Palash V. , Lin Denise , Bahadur Vaibhav
Published: August 2018

Nucleation of clathrate hydrates at low temperatures is constrained by very long induction (wait) times, which can range from hours to days. Electronucleation (application of an electrical potential difference across the hydrate forming solution) can significantly reduce the induction time. This work studies the use of porous open-cell foams of various materials as electronucleation electrodes. Experiments with tetrahydrofuran (THF) hydrates reveal that aluminum and carbon foam electrodes can enable voltage-dependent nucleation, with induction times dependent on the ionization tendency of the foam material. Furthermore, we observe a non-trivial dependence of the electronucleation parameters such as induction time and the recalescence temperature on the water:THF molar ratio. This study further corroborates previously developed hypotheses which associated rapid hydrate nucleation with the formation of metal-ion coordination compounds. Overall, this work studies various aspects of electronucleation with aluminum and carbon foams.
Improved Boiling Heat Transfer in Dry Etched Microchannels With Laser Structured Surfaces
Authors: Sitar Anže , Crivellari Michele , Schille Jörg , Mauersberger Stefan , Löschner Udo , Golobič Iztok
Published: August 2018

The currently available microchannel fabrication techniques ranging from various etching methods and micro electrical discharge machining to laser microfabrication have some apparent advantages and weaknesses when compared one to another. Manufacturing process should satisfy several important criteria: diversity of the working material, the minimal fabricated feature size, the capability of 3D structuring, the precision and surface quality, maximum aspect ratio, the production costs, etc. This study focuses on combining the benefits of dry etching and laser structuring of a silicon substrate in order to produce microchannels with a capability of an improved heat transfer during boiling. The microchannels with a minimal cross section of 50×50 μm were etched in silicon and afterwards laser structuring was employed in order to make surface topography more appropriate for boiling heat transfer. The laser treatment resulted in micron sized cavities at the bottom of the microchannels, which lowered the temperature of the onset of boiling and improved the heat transfer during flow boiling. The performed combination of manufacturing methods proved to be complementary and cost effective.
Spontaneous Displacement of Resident Fluid in Heterogeneous Porous Medium
Authors: Ashraf Shabina , Phirani Jyoti
Published: August 2018

Surface tension driven flow in which one fluid displaces another is of importance in microfluidic devices for diagnostics, lab on chip devices and flow in oil reservoirs. Spontaneous impregnation of a preferentially wetting phase displacing an existing non-wetting phase in a homogeneous porous medium is known to follow diffusive dynamics. However, in a heterogeneous porous medium the hydrodynamic interaction between the narrow and the wide pores significantly alters the impregnation behavior. Previous studies have shown that the imbibing fluid interface leads in the narrow pores contrary to the predictions from the diffusive dynamics of homogeneous porous medium. This is due to the higher suction pressure in the narrow pores which draw fluid from the wide pores. The effect of fluid properties and relative flow properties of the pores with respect to other pores on the non-wetting fluid displacement in the heterogeneous porous medium is still unknown. In the current work, we develop a quasi one-dimensional, lubrication approximation model, which predicts the spontaneous imbibition in a heterogeneous porous medium. We explore all the possible relative fluid properties and flow properties of the layers in the heterogeneous porous medium and show that our model is able to predict the flow behavior in all the cases. We also present the results of the spontaneous imbibition experiments, which agree with our model. The experiments show that the two phase interface progresses faster in the narrow pores as predicted by the one-dimensional model. The result is important for predicting and controlling the flow behavior in a heterogeneous porous medium.
Interface Dynamics During Two Phase Flow in Stratified Porous Medium
Authors: Ambekar Aniket S. , Buwa Vivek V. , Phirani Jyoti
Published: August 2018

Immiscible displacement of a non-wetting fluid by a wetting fluid is important for many fields for example, biomedical devices, paper micro-fluidics, oil reservoirs and water aquifers. In a multi-layered porous medium the displacement velocity and relative position of the layers with respect to each other is significant in determining the flow paths of the fluids. Earlier studies on two-layered porous medium indicate presence of different flow regimes in every layer depending upon the velocity. However, the effect of relative positioning of these layers in different flow regimes is still unknown. In the present work we experimentally show that at low velocity, a capillary regime is developed i.e. the wetting fluid front leads in the least permeable layer, while at high velocity the wetting fluid front leads in the highest permeability layer. At all flow rates, the least permeable layer is found to draw fluid from the high permeability layer due to capillary suction. We also show the effect of relative placement of the layers on the interphase dynamics.
Heat Transfer Model for Liquid-Liquid Taylor Flow in Mini-Scale Coiled Tubing
Authors: Adrugi W. M. , Muzychka Y. S. , Pope K.
Published: August 2018

In this paper, an experimental study on heat transfer enhancement using non-boiling liquid-liquid Taylor flow in mini scale coiled tubing for constant wall temperature conditions is conducted. Coiled copper tubing with different radii of curvature and lengths were used as test sections. Segmented slug flow with water and three low viscosity silicone oils (1 cSt, 3 cSt, 5 cSt) were used to examine the effect of Prandtl number on heat transfer rates in coiled tubing. Additionally, benchmark tests were conducted of single-phase flow in a straight tube. The experimental results are compared with models for liquid-liquid Taylor flow in straight and coiled tubing. This research provides new insights on the enhanced heat transfer rates attainable with using liquid-liquid Taylor flow in mini scale coiled tubing. This enhancement occurs due to internal circulation and secondary flow in the fluid segments.
Saturated Nucleate Pool Boiling of Ethanol-Water Binary Mixtures on Smooth and Enhanced Laser Processed Metal Surfaces
Authors: Zupančič Matevž , Voglar Jure , Gregorčič Peter , Golobič Iztok , Zakšek Peter
Published: August 2018

Pool boiling experiments of water and ethanol-water binary mixtures were conducted on smooth and laser textured stainless steel foils. High-speed IR thermography was used to measure transient temperature field during boiling in order to determine nucleation frequencies, nucleation site densities, bubble activation temperatures, wall-temperature distributions and average superheats as well as heat transfer coefficients. Saturated pool boiling experiments were conducted at atmospheric pressure over a heat flux range of 5–250 kW m−2 for pure water and ethanol-water mixtures (1% and 10% m/m). For both mixtures and both types of surfaces we measured significant decrease in average heat transfer coefficient and increase in bubble activation temperatures in comparison to pure water. However, laser textured surface in average provided around 60% higher nucleation frequency and more than 100% higher nucleation site density compared to smooth surface for both of the tested binary mixtures. Consequentially, heat transfer coefficient was enhanced for more than 30%. Our results show that laser textured surfaces can improve boiling performance for water and ethanol-water mixtures, but at the same time the addition of ethanol reduces heat transfer coefficient despite the enhancement of nucleation site density and nucleation frequency. This is also in agreement with available experimental data and existing theoretical models.
Resource Letter GECC-2: The Greenhouse Effect and Climate Change: The
Intensified Greenhouse Effect
Authors: Schwartz Stephen E.
Published: August 2018

Human activities over the past 200 years have increased Earth's greenhouse effect by about 1% relative to the radiative fluxes that drive the climate system. This Resource Letter introduces the physics of this intensified greenhouse effect and of the processes that govern resultant change in climate and provides resources for further study. Context for this examination is provided in a companion Resource Letter (GECC-1) that examined the radiative fluxes that comprise Earth's climate system and the present-day greenhouse effect. The increase in global temperature and other changes in climate resulting from the intensified greenhouse effect are of great societal concern. Developing prognostic capability to determine these responses to the small perturbations that constitute the intensified greenhouse effect to an accuracy that would be useful to inform policymaking is the major challenge facing climate scientists today.
New strategy for the Puluj-type experiment
Authors: Cheche Tiberius O.
Published: August 2018

The frictional mechanical work is calculated as a function of the rotational direction of the calorimeter in the Puluj-type experimental setup (a calorimeter with water inside). Based on this calculus, a new experimental strategy is proposed for demonstrating the equivalence of heat and mechanical work, which reduces the number of physical quantities that need to be measured during the experiment.
Monthly shots may replace daily anti-HIV pills
Authors: Cohen Jon
Published: August 2018

Long-acting treatments now in clinical trials may work as preventives, too.
Arrival of deadly pig disease could spell disaster for China
Authors: Normile Dennis
Published: August 2018

African swine fever threatens the world's largest pig herd.
Daring to hope
Authors: Wadman Meredith
Published: August 2018

Patients thrill to reports of a promising antisense drug against Huntington disease, but no one is sure yet whether it works.
Endothelial Dab1 signaling orchestrates neuro-glia-vessel communication in the central nervous system
Authors: Segarra Marta , Aburto Maria R. , Cop Florian , Llaó-Cid Cecília , Härtl Ricarda , Damm Miriam , Bethani Ioanna , Parrilla Marta , Husainie Dewi , Schänzer Anne , Schlierbach Hannah , Acker Till , Mohr Laura , Torres-Masjoan Laia , Ritter Mathias , Acker-Palmer Amparo
Published: August 2018

Developing the bloodbrain barrier

During development, signals need to be dynamically integrated by endothelial cells, neurons, and glia to achieve functional neuro-glia-vascular units in the central nervous system. During cortical development, neuronal Dab1 and ApoER2 receptors respond to a guidance cue called reelin. Studying mice, Segarra
et al.
found that Dab1 and ApoER2 are also expressed in endothelial cells (see the Perspective by Thomas). The integration of reelin signaling in endothelial cells and neurons facilitates the communication between vessels, glia, and neurons that is necessary for the correct positioning of neurons during cortical development. This integration is also important for correct communication at the neurovascular unit required for blood-brain barrier integrity in the mature brain.

Science
, this issue p.
eaao2861
; see also p.
754
A high-energy-density lithium-oxygen battery based on a reversible four-electron conversion to lithium oxide
Authors: Xia C. , Kwok C. Y. , Nazar L. F.
Published: August 2018

An elevated lithium battery

Batteries based on lithium metal and oxygen could offer energy densities an order of magnitude larger than that of lithium ion cells. But, under normal operation conditions, the lithium oxidizes to form peroxide or superoxide. Xia
et al.
show that, at increased temperatures, the formation of lithium oxide is favored, through a process in which four electrons are transferred for each oxygen molecule (see the Perspective by Feng
et al.
). Reversible cycling is achieved through the use of a thermally stable inorganic electrolyte and a bifunctional catalyst for both oxygen reduction and evolution reactions.

Science
, this issue p.
777
; see also p.
758
Serotype-specific immunity explains the incidence of diseases caused by human enteroviruses
Authors: Pons-Salort Margarita , Grassly Nicholas C.
Published: August 2018

Hidden truths of enteroviruses

Enteroviruses are important drivers of global health, but few countries undertake enterovirus surveillance. Pons-Salort and Grassly used Japanese surveillance data to model the interplay between the ratio of susceptible and immune individuals, accounting for declining birth and death rates, incomplete surveillance, and seasonality of infection (see the Perspective by Nikolay and Cauchemez). Enteroviruses have highly predictable yet highly nonlinear dynamics. The model also reveals signatures of increased pathogenicity and of antigenic change and transmissibility.

Science
, this issue p.
800
; see also p.
755
The promise and peril of universal health care
Authors: Bloom David E. , Khoury Alexander , Subbaraman Ramnath
Published: August 2018

Population health and national development

Healthy populations translate into productive and stable nations. Universal health care (UHC) is a pragmatic and ethical ideal that, thanks to social and economic progress, seems almost achievable. However, UHC means different things in different contexts. The minimum ideal is that no individual or family should suffer financial hardship because of accessing good-quality medical assistance. Bloom
et al.
review health priorities around the world and what will be needed in terms of skills, funds, and technology to achieve health care access for all.

Science
, this issue p.
eaat9644
Hot lithium-oxygen batteries charge ahead
Authors: Feng Shuting , Lunger Jaclyn R. , Johnson Jeremiah A. , Shao-Horn Yang
Published: August 2018

Molten salt electrolytes and nickel oxide–based electrodes enable four-electron transfer
Connecting immune deficiency and inflammation
Authors: Pasparakis Manolis , Kelliher Michelle
Published: August 2018

RIPK1
mutations result in immune deficiency and autoinflammation in humans
Relation of serum uric acid to asymptomatic proximal extracranial artery stenosis in a middle-aged Chinese population: a community-based cross-sectional study
Authors: Yang Xiaolei , Lv Haichen , Hidru Tesfaldet Habtemariam , Wu Jing , Liu Henghui , Wang Youxin , Liu Kejia , Xia Yunlong , Zhou Yong , Jiang Yinong
Published: August 2018

Objective

Serum uric acid (SUA) has been associated with cardiovascular diseases, including atherosclerosis and carotid artery stenosis. However, data on the relationship between SUA level and proximal extracranial artery stenosis (PEAS) are limited. Therefore, this study investigates the association between SUA levels and the risk of PEAS in asymptomatic Chinese population.

Setting

This community-based cross-sectional study was conducted in Jidong Community Hospital, Tangshan, Hebei, China between July 2013 and August 2014.

Participants

The study examined 3325 asymptomatic participants (40–60 years) to evaluate the risk of PEAS.

Results

For the participants stratified into quartiles based on gender-specific SUA levels, the prevalence of PEAS increased from Q1 to Q4 from 12.3% to 29.8% in the vertebral artery (VA), and from 2.8% to 5.8% in the common carotid artery. The proportion of PEAS relative to the detected number of arterial stenosis was lower in Q1 than in Q2–Q4. The multivariable ORs and 95% CI of PEAS in the second through fourth compared with the lowest quartiles for arterial stenosis were 1.278 (0.980 to 1.665), 1.117 (0.851 to 1.468) and 1.375 (1.033 to 1.830) (ptrend=0.0399); and for VA stenosis, 1.285 (0.966 to 1.709), 1.085 (0.808 to 1.457) and 1.439 (1.061 to 1.952) (ptrend=0.0235).

Conclusion

Elevated SUA concentration is significantly associated with PEAS in an asymptomatic middle-aged Chinese population, and vertebral arteries appeared to be the most vulnerable vessels.
Impact of the communication and patient hand-off tool SBAR on patient safety: a systematic review
Authors: Müller Martin , Jürgens Jonas , Redaèlli Marcus , Klingberg Karsten , Hautz Wolf E , Stock Stephanie
Published: August 2018

Objectives

Communication breakdown is one of the main causes of adverse events in clinical routine, particularly in handover situations. The communication tool SBAR (situation, background, assessment and recommendation) was developed to increase handover quality and is widely assumed to increase patient safety. The objective of this review is to summarise the impact of the implementation of SBAR on patient safety.

Design

A systematic review of articles published on SBAR was performed in PUBMED, EMBASE, CINAHL, Cochrane Library and PsycINFO in January 2017. All original research articles on SBAR fulfilling the following eligibility criteria were included: (1) SBAR was implemented into clinical routine, (2) the investigation of SBAR was the primary objective and (3) at least one patient outcome was reported.

Setting

A wide range of settings within primary and secondary care and nursing homes.

Participants

A variety of heath professionals including nurses and physicians.

Primary and secondary outcome measures

Aspects of patient safety (patient outcomes) defined as the occurrence or incidence of adverse events.

Results

Eight studies with a before–after design and three controlled clinical trials performed in different clinical settings met the inclusion criteria. The objectives of the studies were to improve team communication, patient hand-offs and communication in telephone calls from nurses to physicians. The studies were heterogeneous with regard to study characteristics, especially patient outcomes. In total, 26 different patient outcomes were measured, of which eight were reported to be significantly improved. Eleven were described as improved but no further statistical tests were reported, and six outcomes did not change significantly. Only one study reported a descriptive reduction in patient outcomes.

Conclusions

This review found moderate evidence for improved patient safety through SBAR implementation, especially when used to structure communication over the phone. However, there is a lack of high-quality research on this widely used communication tool.

Trial registration

none
Engaging patients and family members in the evaluation of a mental health patient portal: protocol for a mixed-methods study
Authors: Strudwick Gillian , Kuziemsky Craig , Booth Richard G , Collins Sarah , Chyjek Anna , Sakal Moshe , Harris Alexandra , Strauss John
Published: August 2018

Introduction

Twenty per cent of Canadians will experience a mental illness in any year. Mental health patient portals have been developed to support these individuals in taking more control over their own mental health and care. This may be done through electronic access to their health records and other supportive functions like completion of online self-assessments. To date, there has been limited research into the value that these portals may provide within mental health contexts. This study will identify what value mental health patient portals may offer to patients and their family members.

Methods and analysis

This study will use a mixed-methods design. Patients will complete a survey consisting of validated instruments at the time of enrolment in the portal, and at 3 and 6 months of portal use. Patient and family member focus groups will be conducted. Portal usage data will be collected to identify if there are differences in outcomes based on usage. The study will be done at Canada’s largest mental health and addiction teaching hospital, and will be conducted using a patient and family-oriented research approach, engaging these important representatives in all stages of the research process. The primary data analysis for the survey portion of the study will be done using linear mixed-effect models, assessing the differences between patients with different portal usage levels. A thematic analysis will be conducted of the focus group transcripts.

Ethics and dissemination

Approval from the study site’s Research Ethics Board has been obtained. The dissemination of findings of this study will be done through presentations at conferences, as well as a formal peer-reviewed journal article. Additionally, the research team will work with a group of patients and family members to identify opportunities to complete knowledge translation and dissemination activities in non-traditional venues.
Suspected intrapericardial lipoma in a standard schnauzer
Authors: Jenkins Paul , Kuan Soo , Brain Philip
Published: August 2018

A five-year-old, male, neutered standard schnauzer presented for vomiting, diarrhoea and fever. A large intrapericardial fatty mass was identified on advanced imaging. The patient underwent a median sternotomy and exploratory coeliotomy to remove the fatty mass measuring 100 mm x 76 mm x 66 mm, the histopathology of which revealed a large fatty mass with necrosis and inflammation. This is the largest reported intrapericardial fatty mass in the veterinary literature. CT at 28 weeks postoperatively revealed no evidence of recurrence.
Maternal cardioautonomic responses during and following exercise throughout pregnancy
Authors: Purdy Graeme M. , James Marina A. , Wakefield Paige K. , Skow Rachel J. , Van Diepen Sean , May Linda E. , Davenport Margie H. , Steinback Craig D.
Published: August 2018

Blood pressure regulation during pregnancy is poorly understood. Cardiovagal baroreflex gain (BRG) is an important contributor to blood pressure regulation through its influence on heart rate. Heart rate fluctuations occur in response to various physiological stimuli and can be measured using heart rate variability (HRV). It is unclear how these mechanisms operate during pregnancy, particularly with regard to exercise. We examined BRG and HRV prior to, during, and following prenatal exercise. Forty-three pregnant (n = 10 first trimester (TM1), n = 17 second trimester (TM2), n = 16 third trimester (TM3)) and 20 nonpregnant (NP) women underwent an incremental peak exercise test. Beat-by-beat blood pressure (photoplethysmography) and heart rate (lead II electrocardiogram) were measured throughout. BRG (the slope of the relationship between fluctuations in systolic blood pressure and the R–R interval) and HRV (root mean square of the successive differences; RMSSD) were assessed at rest, during steady-state exercise (EX), and during active recovery. BRG decreased with gestation and was lower in the TM3 group than in the NP group (17.9 ± 6.9 ms/mm Hg vs 24.8 ± 7.4 ms/mm Hg, p = 0.017). BRG was reduced during EX in all groups. Resting HRV (RMSSD) also decreased with gestation and was lower in the TM3 group than in the NP group (29 ± 17 ms vs 48 ± 20 ms, p < 0.001). RMSSD was blunted during EX in all groups compared with rest. During active recovery, RMSSD was further blunted compared with EX in the NP group but not during pregnancy (TM1, TM2, and TM3). Compared with the nonpregnant controls, the pregnant women had lower BRG and HRV at rest, but comparable cardioautonomic control during both exercise and active recovery following peak exercise.
Scots pine provenance affects the emission rate and chemical composition of volatile organic compounds of forest floor
Authors: Kivimäenpää Minna , Markkanen Juha-Matti , Ghimire Rajendra P. , Holopainen Toini , Vuorinen Martti , Holopainen Jarmo K.
Published: August 2018

Scots pine (Pinus sylvestris L.) is an important source of biogenic volatile organic compounds (BVOCs) in the boreal zone. BVOC emission rate and profile affect air quality, climate forcing, plant stress tolerance, and thus the growing conditions of forests. BVOC emission profile of shoots and forest floor, as well as emission rates from forest floor, were studied in a latitudinal provenance experiment with 19-year-old Scots pine common garden in Central Finland. The provenances studied were Saaremaa (SAA, 58°22′), Korpilahti (KOR, 62°0′), Suomussalmi (SUO, 65°10′), and Muonio (MUO, 67°56′). A chemotype with high proportion of Δ-3-carene, terpinolene, sabinene, γ-terpinene, and α-terpinene was significantly more common for the southern SAA than the northern SUO and MUO provenances. A chemotype with high proportion of α-pinene, β-pinene, limonene, and myrcene was more common in the three northernmost provenances. The main compounds emitted by forest floor were α-pinene, Δ-3-carene, and camphene. Similarly to shoot emissions, forest floor emissions from SAA had highest proportion of Δ-3-carene. Average total VOC emission rate from forest floor was 50 μg·m−2·h−1 at the end of August. Total emission rates were 65% higher in KOR than in MUO. High emission rates were explained by the high amount of decomposing needle litter and low moss coverage.
Hidden participants and unheard voices? A systematic review of gender, age, and other influences on local and traditional knowledge research in the North
Authors: Hitomi Maaya K. , Loring Philip A.
Published: August 2018

Local, lay, and traditional ecological knowledge (LTK) is widely discussed in academic studies of climatic and environmental change. Here, we report on a systematic literature review that examines the role of such factors as gender, age, and scholarly networks in shaping LTK research. We focused on research in the circumpolar North, where LTK research has been ongoing for at least four decades. We explored how recruitment approaches and research methods can circumscribe local expertise and found that much of the literature fails to adequately report sampling and participant demographics. There is an apparent bias towards male knowledge-holders, usually hunters and Elders, over women and youth. Studies were largely led by male authors, and male authors outnumbered female authors 2:1. We also identified two potential “invisible colleges” in the literature—communities of practice linked by one or a few authors. We discuss our findings through the lens of “intersectionality”, which captures how power differences at play within communities, whether around age or gender or some other social categorization, contribute to the creation of multiple kinds of knowledge. We conclude with a discussion of how we can improve this area of research by challenging assumptions and collaborating with a wider range of individuals.
Graphical virtual links and a polynomial for signed cyclic graphs
Authors: Deng Qingying , Jin Xian’an , Kauffman Louis H.
Published: August 2018

For a signed cyclic graph [Formula: see text], we can construct a unique virtual link [Formula: see text] by taking the medial construction and converting 4-valent vertices of the medial graph to crossings according to the signs. If a virtual link can occur in this way then we say that the virtual link is graphical. In this paper, we shall prove that a virtual link [Formula: see text] is graphical if and only if it is checkerboard colorable. On the other hand, we introduce a polynomial [Formula: see text] for signed cyclic graphs, which is defined via a deletion-marking recursion. We shall establish the relationship between [Formula: see text] of a signed cyclic graph [Formula: see text] and the bracket polynomial of one of the virtual link diagrams associated with [Formula: see text]. Finally, we give a spanning subgraph expansion for [Formula: see text].
The marginally trapped surfaces in spheroidal spacetimes
Authors: Rahim Rehana , Giusti Andrea , Casadio Roberto
Published: August 2018

We study the location of marginally trapped surfaces in spacetimes resulting from an axial deformation of static isotropic systems, and show that the Misner–Sharp mass evaluated on the corresponding undeformed spherically symmetric space provides the correct gravitational radius to locate the spheroidal horizon.
Nuclear energy excitation by Bohr Hamiltonian for triaxial nuclei using Killingbeck plus Morse potential
Authors: Tchana Mbadjoun B. , Ema’a Ema’a J. M. , Ele Abiama P. , Ben-Bolie G. H. , Owono Ateba P.
Published: August 2018

This paper proposes an improved potential for the [Formula: see text]-part of the collective Bohr Hamiltonian, namely, a Killingbeck plus Morse potential, while the [Formula: see text]-part is solved for a triaxial deformation close to [Formula: see text]. The Asymptotic Iteration Method is used, involving the Pekeris approximation, to calculate the energy eigenvalues and the eigenfunctions after an exact separation of the Bohr Hamiltonian into its variables is achieved. The results of these calculations are applied for energy spectra of the low-lying states and for corresponding [Formula: see text] quadrupole transition probabilities of the [Formula: see text] isotopes. Moreover, the results of the present solution are compared with those of the well-known [Formula: see text] and [Formula: see text] models.
Recent developments in dislocation pattern dynamics: Current opinions and perspectives
Authors: Lyu Dandan , Li Shaofan
Published: August 2018

The development of crystal plasticity theory based on dislocation patterns dynamics has been an outstanding problem in materials science and condensed matter of physics. Dislocation is the origin of crystal plasticity, and it is both the individual dislocation behavior as well as the aggregated dislocations behaviors that govern the plastic flow. The interactions among dislocations are complex statistical and stochastic events, in which the spontaneous emergence of organized dislocation patterns formations is the most critical and intriguing events. Dislocation patterns consist of quasi-periodic dislocation-rich and dislocation poor regions, e.g. cells, veins, labyrinths, ladders structures, etc. during cyclic loadings. Dislocation patterns have prominent and decisive effects on work hardening and plastic strain localization, and thus these dislocation micro-structures are responsible to material properties at macroscale. This paper reviews the recent developments of experimental observation, physical modeling, and computer modeling on dislocation microstructure. In particular, we focus on examining the mechanism towards plastic deformation. The progress and limitations of different experiments and modeling approaches are discussed and compared. Finally, we share our perspectives on current issues and future challenges in both experimental, analytical modeling, and computational aspects of dislocation pattern dynamics.
Workload frequency scaling law
Authors: Mubeen Noor
Published: August 2018

Workload scalability has a cascade relation via the scale factor.
Enhancing Flash Memory Reliability by Jointly Considering Write-back Pattern and Block Endurance
Authors: Chen Tseng-Yi , Chang Yuan-Hao , Kuan Yuan-Hung , Yang Ming-Chang , Chang Yu-Ming , Hsiu Pi-Cheng
Published: August 2018

Owing to high cell density caused by the advanced manufacturing process, the reliability of flash drives turns out to be rather challenging in flash system designs. To enhance the reliability of flash drives, error-correcting code (ECC) has been widely utilized in flash drives to correct error bits during programming/reading data to/from flash drives. Although ECC can effectively enhance the reliability of flash drives by correcting error bits, the capability of ECC would degrade while the program/erase (P/E) cycles of flash blocks is increased. Finally, ECC could not correct a flash page, because a flash page contains too many error bits. As a result, reducing error bits is an effective solution to further improve the reliability of flash drives when a specific ECC is adopted in the flash drive. This work focuses on how to reduce the probability of producing error bits in a flash page. Thus, we propose a pattern-aware write strategy for flash reliability enhancement. The proposed write strategy considers both the P/E cycle of blocks and the pattern of written data while a flash block is allocated to store the written data. Since the proposed write strategy allocates young blocks (respectively, old blocks) for hot data (respectively, cold data) and flips the bit pattern of the written data to the appropriate bit pattern, the proposed strategy can effectively improve the reliability of flash drives. The experimental results show that the proposed strategy can reduce the number of error pages by up to 50%, compared with the well-known DFTL solution. Moreover, the proposed strategy is orthogonal with all ECC mechanisms so that the reliability of the flash drives with ECC mechanisms can be further improved by the proposed strategy.
GitOps
Authors: Limoncelli Thomas A.
Published: August 2018

IaC + PR = GitOps
'Nothing about me without me'
Authors: Wilcox Lauren
Published: August 2018

This forum is dedicated to personal health in all its many facets: decision making, goal setting, celebration, discovery, reflection, and coordination, among others. We look at innovations in interactive technologies and how they help address current critical healthcare challenges.
--- Yunan Chen, Editor
Lean UX communication strategies for success in large organizations
Authors: Nudelman Greg
Published: August 2018

This forum is dedicated to maximizing the success of HCI practitioners within the frenetic world of product and service design. It focuses on UX strategy approaches, leadership, management techniques, and above all the challenge of bringing HCI to peer-level status with longstanding business disciplines such as marketing and engineering. ---
Daniel Rosenberg, Editor
Borders in the cloud
Authors: Kirkpatrick Keith
Published: August 2018

New data protection laws raise questions about whether certain jurisdictions are trying to thwart the ability of foreign governments to obtain data on their citizens.
Discovering bugs, or ensuring success?
Authors: Bugayenko Yegor
Published: August 2018

The
Communications
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Finding errors is not the same as making certain a software product works correctly.
Inhibition of the extrinsic or intrinsic coagulation pathway during pneumonia-derived sepsis
Authors: Stroo Ingrid , Ding Chao , Novak Andreja , Yang Jack , Roelofs Joris J. T. H. , Meijers Joost C. M. , Revenko Alexey S. , van ’t Veer Cornelis , Zeerleder Sacha , Crosby Jeff R. , van der Poll Tom
Published: August 2018

Pneumonia is the most frequent cause of sepsis, and Klebsiella pneumoniae is a common pathogen in pneumonia and sepsis. Infection is associated with activation of the coagulation system. Coagulation can be activated by the extrinsic and intrinsic routes, mediated by factor VII (FVII) and factor XII (FXII), respectively. To determine the role of FVII and FXII in the host response during pneumonia-derived sepsis, mice were treated with specific antisense oligonucleotide (ASO) directed at FVII or FXII for 3 wk before infection with K. pneumoniae via the airways. FVII ASO treatment strongly inhibited hepatic FVII mRNA expression, reduced plasma FVII to ~25% of control, and selectively prolonged the prothrombin time. FXII ASO treatment strongly suppressed hepatic FXII mRNA expression, reduced plasma FXII to ~20% of control, and selectively prolonged the activated partial thromboplastin time. Lungs also expressed FVII mRNA, which was not altered by FVII ASO administration. Very low FXII mRNA levels were detected in lungs, which were not modified by FXII ASO treatment. FVII ASO attenuated systemic activation of coagulation but did not influence fibrin deposition in lung tissue. FVII ASO enhanced bacterial loads in lungs and mitigated sepsis-induced distant organ injury. FXII inhibition did not affect any of the host response parameters measured. These results suggest that partial inhibition of FVII, but not of FXII, modifies the host response to gram-negative pneumonia-derived sepsis.
Contribution of peripheral airway function to changes in FEV1/FVC and RV/TLC with aging
Authors: Htun Christopher , Pope Alun , Lahzami Samir , Luo Darren , Schoeffel Robin E. , Farrow Catherine E. , Phillips Craig L. , Robinson Paul D. , King Gregory G.
Published: August 2018

Multiple breath nitrogen washout (MBNW) indices provide insight into ventilation heterogeneity globally [lung clearance index (LCI)] and within acinar (Sacin) and conducting (Scond) airways. Normal aging leads to an accelerated deterioration of Sacinin older adults, but little is known about the contribution of peripheral airway function to changes in pulmonary function indices reflecting expiratory airflow [forced expiratory volume in one second (FEV1)/forced vital capacity (FVC)] and gas trapping [residual volume (RV)/total lung capacity (TLC)] with aging. We aimed to examine associations between MBNW and FEV1/FVC as well as RV/TLC in healthy adults, and to determine if these relationships differ in older (≥50 yr) versus younger subjects (<50 yr). Seventy-nine healthy adult volunteers aged 23–89 yr with no cardiac or respiratory disease and a smoking history of <5 pack-years underwent spirometry, plethysmography, and MBNW. After adjustment for sex, height, and body mass index, the following relationships were present across the entire cohort: Sacinwas inversely related to FEV1/FVC (R2 = 0.22, P < 0.001); Sacinand Scondwere positively related to RV/TLC (R2 = 0.53, P < 0.001); on separate analyses, the relationship between Sacinand FEV1/FVC was strongest in the older group (R2 = 0.20, P = 0.003) but markedly weaker in the younger group (R2 = 0.09, P = 0.04); and Sacinand Scondwere related to RV/TLC in older (R2 = 0.20, P = 0.003) but not younger subgroups. No relationships were observed between LCI and FEV1/FVC or RV/TLC. Changes in FEV1/FVC and RV/TLC are at least in part due to changes in peripheral airway function with aging. Further studies of the relationships between MBNW and standard pulmonary function indices may prove useful for their combined application and interpretation in obstructive airways disease.

NEW & NOTEWORTHY This study explores associations between multiple breath nitrogen washout (MBNW) and standard pulmonary function indices reflecting expiratory airflow [forced expiratory volume in one second (FEV1)/forced vital capacity (FVC)] and gas trapping [residual volume (RV)/total lung capacity (TLC)] in healthy adults across a wide range of ages. We have demonstrated statistically significant relationships between MBNW and FEV1/FVC as well as RV/TLC. These findings provide novel evidence of the contribution of peripheral airway function to changes in standard pulmonary function indices with aging.
Anti‐Inflammatory and Antioxidant Actions of Methyl Jasmonate Are Associated with Metabolic Modifications in the Liver of Arthritic Rats
Authors: Sá-Nakanishi Anacharis B. , Soni-Neto Jamil , Moreira Lucas S. , Gonçalves Geferson A. , Silva Francielli M. S. , Bracht Lívia , Bersani-Amado Ciomar A. , Peralta Rosane M. , Bracht Adelar , Comar Jurandir F.
Published: August 2018

Methyl jasmonate (MeJA) is a fatty acid‐derived cyclopentanone which shares structural similarities with prostaglandins and has been under study as a promising anti‐inflammatory agent. This study investigated the actions of MeJA on systemic inflammation and oxidative status in rats with adjuvant‐induced arthritis, a model for rheumatoid arthritis. MeJA (75 to 300 mg·kg−1) was administrated orally during 18 days after arthritis induction with Freund’s adjuvant. Articular and systemic inflammation was greatly increased in arthritic rats, likewise the oxidative stress in plasma and liver. The hepatic glucokinase activity and glycolysis were increased in arthritic rats. MeJA decreased most inflammatory parameters and abolished the increased protein carbonylation in plasma and liver, diminished the increased hepatic ROS content, and restored the hepatic GSH/GSSG ratio in arthritic rats. However, the MeJA treatment decreased the hepatic glucokinase activity and glycolysis and stimulated mitochondrial ROS production in healthy and arthritic rats. Oxygen uptake was increased by MeJA only in livers from treated arthritic rats. This action may bear relation to the increased activity of mitochondrial NADP+‐dependent enzymes to provide reducing equivalents for the glutathione cycle. These beneficial effects, however, are associated with a decreased glucose flux through the glycolysis in the liver of arthritic and healthy rats.
A Real-Time Obstacle Avoidance Method for Autonomous Vehicles Using an Obstacle-Dependent Gaussian Potential Field
Authors: Cho Jang-Ho , Pae Dong-Sung , Lim Myo-Taeg , Kang Tae-Koo
Published: August 2018

A new obstacle avoidance method for autonomous vehicles calledobstacle-dependent Gaussian potential field(ODG-PF) was designed and implemented. It detects obstacles and calculates the likelihood of collision with them. In this paper, we present a novel attractive field and repulsive field calculation method and direction decision approach. Simulations and the experiments were carried out and compared with other potential field-based obstacle avoidance methods. The results show that ODG-PF performed the best in most cases.
SPR-Enhanced Fluorescence of Solid Organic Dye Films
Authors: Fu Qing , Zhang Xiaolin , Yan Peipei , Wang Shichao , Wang Xinzhi , Wang Yao , Huang Linjun , Wang Yanxin , Liu Haiyan , Belfiore Laurence A. , Tang Jianguo
Published: August 2018

This paper presents strong fluorescence of spin-coated fluorescent solid organic dye films (SODF) enhanced by surface plasmonic resonance (SPR). In order to manifest the influence of SPR effect on enhancement of organic dye (OD) fluorescence, the organic dye embedded Ag@SiO2 fluorescent films were developed on the glass sheet substrate, in which Ag@SiO2 nanoparticles were embedded in the middle and organic dye was as upper layer. The morphology of the SODFs with and without Ag@SiO2 particles was studied by SEM and EDX, and the tests revealed that the Ag@SiO2 nanoparticles distributed evenly between glass sheet and OD layer. Optical properties were characterized by UV absorption and fluorescence spectroscopy; the lifetime of SODF was tested to discuss the mechanism of SPR enhancement of fluorescence. The results proved that the existence of Ag@SiO2 particles enhanced the fluorescence intensity for 7 times and thus proved the SPR effect for organic dye, especially when the organic dye is the solid films. Therefore, the most important is the creation that the SPR effect of Ag@SiO2 particles works very well under solid organic dye coverage.
Cost-Optimization Problem with a Soft Time Window Based on an Improved Fuzzy Genetic Algorithm for Fresh Food Distribution
Authors: Wang Yong Ming , Yin Hong Li
Published: August 2018

Given the increasing demand for fresh food quality, fresh food plants must manage not only product cost but more importantly the product quality. The transportation requirements for fresh food delivery have been continuously increasing. The purpose of this paper is to develop a method to ensure that fresh food can be delivered just in time and with minimum total cost while maintaining the quality of fresh food. Considering that fresh food plants need multiple trucks to deliver multiple products to numerous geographically dispersed customers, the delivery of fresh food is considered in two stages in our study. The first stage is cluster consumers; that is, we determine to which consumers each truck is responsible for delivery. The second stage, which is based on the consumer grouping results, develops a total cost model that includes the transportation, refrigerated, devalued, and penalty costs incurred during distribution. This model is used to determine the optimal route selection, the temperature control, and the average speed of each truck in distribution. This paper designs decision variables based on a customer’s seven requirement attributes; it also proposes a fuzzy clustering method for grouping customers and improves a fuzzy genetic algorithm that is used to solve the proposed total cost model. The application of the proposed method is demonstrated using an example. The experimental results show that the proposed method has better performance than that of a traditional genetic algorithm. This research work provides an optimal distribution total cost decision method for the logistics managers. This research also provides an effective means to ensure the safety of fresh food.