bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of platelet‐derived extracellular vesicles in plateletpheresis concentrates: a multicenter study
Authors: Black Anne , Orsó Evelyn , Kelsch Reinhard , Pereira Melanie , Kamhieh‐Milz Julian , Salama Abdulgabar , Fischer Michael B. , Meyer Eduardo , Frey Beat M. , Schmitz Gerd
Published: April 2017

BACKGROUND

Routine quantification of platelet‐derived extracellular vesicles (PL‐EVs) may be useful in the quality control (QC) of platelet concentrates (PCs). The aim of this multicenter study was to establish and validate a consensus protocol for the standardized PL‐EV quantification using conventional flow cytometers.

STUDY DESIGN AMD METHODS

Eighty‐six PCs were investigated in five blood transfusion centers (A‐E) on Days 0 and 5. The centers used different apheresis instruments: Trima Accel (n = 56) and/or Amicus (n = 30). PCs were prepared using standard methods (sd‐PCs; n = 73; A‐D) or with pathogen inactivation (PI [PI‐PCs]; n = 13; E). Platelet (PLT) count was determined using conventional hematology analyzers. PLT degranulation (P‐selectin expression in response to thrombin receptor PAR1 activation) and PL‐EVs were analyzed by flow cytometry.

RESULTS

During storage, PLT count remained stable in 58 PCs (A, C, E), whereas a decrease was observed in 12 PCs (B). PLT degranulation declined in all PCs (p < 0.001) and PL‐EVs increased in 74 PCs (A, C‐E; p < 0.001). Certain donor variables (e.g., plasma cholesterol, immature PLT fraction) were associated with lower PL‐EVs. In Trima‐produced PCs, PL‐EVs were significantly lower (D) and PLT degranulation was superior compared to PCs prepared with the Amicus (A, D). PL‐EVs were 10‐fold lower in PI‐PCs, compared to sd‐PCs. However, similar QC trends were demonstrated for both PC groups during storage.

CONCLUSION

PL‐EV analysis in a QC program of PCs was successfully performed with results comparable among the different centers. PLT degranulation and vesiculation were primarily affected by preparation techniques.
A Randomized Controlled Trial Provides Evidence to Support Aromatherapy to Minimize Anxiety in Women Undergoing Breast Biopsy
Authors: Trambert Renee , Kowalski Mildred Ortu , Wu Betty , Mehta Nimisha , Friedman Paul
Published: April 2017

Background

Aromatherapy has been used to reduce anxiety in a variety of settings, but usefulness associated with breast biopsies has not been documented.

Aims

This study was conducted in women undergoing image‐guided breast biopsy. We explored the use of two different aromatherapy scents, compared to placebo, aimed at reducing anxiety with the intent of generating new knowledge.

Methods

This was a randomized, placebo‐controlled study of two different types of external aromatherapy tabs (lavender‐sandalwood and orange‐peppermint) compared with a matched placebo‐control delivery system. Anxiety was self‐reported before and after undergoing a breast biopsy using the Spielberger State Anxiety Inventory Scale.

Results and Findings

Eighty‐seven women participated in this study. There was a statistically significant reduction in self‐reported anxiety with the use of the lavender‐sandalwood aromatherapy tab compared with the placebo group (p = .032). Aromatherapy tabs reduced anxiety during image‐guided breast biopsy.

Linking Evidence to Action

The completion of the biopsy provided some relief from anxiety in all groups. The use of aromatherapy tabs offers an evidence‐based nursing intervention to improve adaptation and reduce anxiety for women undergoing breast biopsy. Lavender‐sandalwood aromatherapy reduced anxiety and promoted adaptation more than orange‐peppermint aromatherapy or placebo.
Anti‐CD40 antibody‐mediated costimulation blockade promotes long‐term survival of deep‐lamellar porcine corneal grafts in non‐human primates
Authors: Kim Jaeyoung , Kim Dong Hyun , Choi Hyuk Jin , Lee Hyun Ju , Kang Hee Jung , Park Chung‐Gyu , Hwang Eung‐Soo , Kim Mee Kum , Wee Won Ryang
Published: April 2017

Background

Corneal xenotransplantation is an effective solution for the shortage of human donor corneas, and the porcine cornea may be a suitable candidate for the donor cornea because of its optical similarity with humans. However, it is necessary to administer additional immunosuppressants to overcome antigenic differences. We aimed to investigate the feasibility of porcine corneas with anti‐CD40 antibody‐mediated costimulation blockade in a clinically applicable pig‐to‐non‐human primate corneal xenotransplantation model.

Methods

Five Chinese rhesus macaques underwent deep‐lamellar corneal transplantation using clinically acceptable sized (7.5 mm diameter) porcine corneal grafts. The anti‐CD40 antibody was intravenously administered on a programmed schedule. Graft survival, central corneal thickness, and intraocular pressure were evaluated. Changes in effector and memory T and B cell subsets and anti‐αGal and donor‐specific antibodies were investigated in the blood, and the changes in complement levels in the aqueous humor and blood were evaluated. Memory cell profiles in the anti‐CD40 antibody‐treated group were compared with those from the anti‐CD154 antibody‐treated group or rejected controls presented in our previous report. The changes in anti‐αGal, non‐αGal, and donor‐specific antibodies after 6 months were compared with baseline values.

Results

Anti‐CD40 antibody‐mediated costimulation blockade resulted in the successful survival of xenocorneal grafts (>389, >382, >236, >201, and >61 days), with 80% reaching 6 months of survival. Injection of anti‐CD40 antibody considerably reduced the infiltration of inflammatory cells into the grafts and significantly blocked the complement response in the aqueous humor (P=.0159, Mann‐Whitney U test). Systemic expansion of central or effector memory T cells was abrogated in the anti‐CD40 antibody‐treated primates compared with those in the rejected controls (P<.05, Mann‐Whitney U test) or those in the anti‐CD154 antibody‐treated primates (P>.05, Mann‐Whitney U test). The levels of anti‐αGal, non‐αGal, and donor‐specific antibodies at 6 months were not significantly increased compared with baseline levels (P>.05, Wilcoxon signed rank test).

Conclusions

An anti‐CD40 antibody‐mediated blockade appears to be effective immunosuppressive approach for porcine corneal deep‐lamellar xenotransplantation in primates.
The Impact of Simultaneously Applying Normal Stress and Vibrotactile Stimulation for Feedback of Exteroceptive Information
Authors: Reza Motamedi M. , Otis Martin , Duchaine Vincent
Published: April 2017

Commercially available prosthetic hands do not convey any tactile information, forcing amputees to rely solely on visual attention. A promising solution to this problem is haptics, which could lead to new prostheses in which tactile information is conveyed between the amputee and the artificial limb. However, the haptic feedback must be optimized so that amputees can use it effectively; and although several studies have examined how specific haptic feedback systems can transmit certain types of tactile information, there has not yet been much research on the effects of superposing two or more types of feedback at the same location, which might prove to be more effective than using a single type of feedback alone. This paper investigates how the simultaneous application of two different types of haptic feedback—vibration and normal stress—impacts the human sensory perception of each separate feedback type. These stimuli were applied to glabrous skin on the forearms of 14 participants. Our experiments tested whether participants experienced more accurate sensory perception, compared to vibration or normal stress alone, when vibration was applied at the same time as the normal stress, at either the same location, or at a different location 6 cm away. Results indicate that although participants' perception of the normal stress diminished when vibration was applied at the same location, the same combination improved their perception of the vibration. Apparently, vibration has a negative impact upon the ability to perceive normal stress, whether applied at the same or a different location; whereas the opposite is true for the effect of normal stress upon the perception of vibration.
A New Stress Intensification Factor of Pipe-In-Pipes Based on Finite Element Analyses
Authors: Kim Se-Chang , Choi Jae-Boong , Ki Kim Moon , Kim Hyun-Su , Huh Nam-Su
Published: April 2017

For the design of a transmission piping system, a stress intensification factor (SIF) is generally used for the stress calculations of piping components due to external forces, and the solutions for the single-walled piping components can be found in the existing design codes. However, it is quite difficult to obtain the reliable estimations for pipe-in-pipes (PIPs) from the existing solutions, because the PIPs show significantly different behaviors compared to the single-walled piping components due to the restraint effect induced by the outer pipe of the PIP. In this paper, the estimation schemes for the stress behaviors of the PIPs were proposed based on the detailed finite element (FE) analyses. In order to quantify the restraint effect, the FE analyses were conducted by considering various geometric variables of the PIPs under an internal pressure and a global bending moment. Based on the FE results, the tabular and closed-form solutions of the SIFs of PIPs were newly proposed. Finally, the proposed SIF estimations were validated against numerical results.
Determination of Failure Pressure Modes of the API Specification 12F Shop-Welded, Flat-Bottom Tanks
Authors: Rondon Andres , Guzey Sukru
Published: April 2017

Shop–welded, flat-bottom tanks for storage of production liquids are designed and fabricated in specific dimensions and capacities for internal pressures close to atmospheric pressure in accordance with the API 12F specification. This study addresses the failure pressure on the eleven (11) current API 12F shop-welded steel tanks as well as two proposed sizes through finite element and stress analysis of more than 350 different tank models. An elastic analysis was carried out to determine the yielding pressure of the shell-to-bottom and roof-to-shell joints. An elastic buckling analysis and a post-buckling analysis including imperfections was performed to determine the buckling modes of the equipment. The redistribution of stresses due to inelastic deformations and plastic collapse were evaluated through a plastic stress analysis considering the stress–strain hardening of the ASTM A36 mild steel material. Moreover, the design pressure increase to failure pressure or 24 oz/in2 (10.3 kPa) was investigated regarding the stress levels and bottom uplift of the 13 flat-bottom tanks. The presented research provides meaningful insights and engineering calculations to evaluate the current design of the API 12F shop-welded, flat-bottom tanks as well as to establish new design internal pressures guaranteeing a safe performance of the equipment.
Fission Track Detection Using Automated Microscopy
Authors: Weiss Aryeh M. , Halevy Itzhak , Dziga Naida , Chinea-Cano Ernesto , Admon Uri
Published: April 2017

Detection of microscopic fission track (FT) star-shaped clusters, developed in a solid state nuclear track detector (SSNTD) by etching, created by fission fragments emitted from particles of fissile materials irradiated by neutrons, is a key technique in nuclear forensics and safeguards investigation. It involves scanning and imaging of a large area, typically 100–400 mm2, of a translucent SSNTD (e.g., polycarbonate sheet, mica, etc.) to identify the FT clusters, sparse as they may be, that must be distinguished from dirt and other artifacts present in the image. This task, if done manually, is time consuming, operator dependent, and prone to human errors. To solve this problem, an automated workflow has been developed for (a) scanning large area detectors, in order to acquire large images with adequate high resolution, and (b) processing the images with a scheme, implemented in ImageJ, to automatically detect the FT clusters. The scheme combines intensity-based segmentation approaches with a morphological algorithm capable of detecting and counting endpoints in putative FT clusters in order to reject non-FT artifacts. In this paper, the workflow is described, and very promising preliminary results are shown.
Children’s voices in system reform - A case study on children and young people’s participation within the modernisation of Child, Youth and Family
Authors: Fitzmaurice Luke
Published: April 2017

INTRODUCTION: In 2015, an independent panel was appointed to overhaul Aotearoa New Zealand’s care, protection and youth justice systems. This article discusses the mechanisms used to involve children and young people in that review and evaluates the extent to which these mechanisms lived up to best practice.METHOD: The article takes a case study approach: exploring the ways in which the Expert Panel enabled children and young people to have a meaningful role in the process. The author was a member of the Expert Panel Secretariat, which supported the Panel during the review. The impact that young people’s voices had on the process motivated this research in order to explore what made their input effective, and what could have been improved.FINDINGS: The Expert Panel made young people’s participation in the review meaningful by valuing their lived experience and providing the necessary support to enable them to have their voices heard. Although more could have been done to reduce the risk of filtering and assumed representation, the Panel’s approach to involving children and young people in the design process was strongly in line with a childhood studies approach to children and young people’s participation.CONCLUSIONS: The outcomes of this process challenge the assumption that giving young people decision-making power is what makes this type of process effective. It may be that decision-making influence, not decision-making power, is what makes young people’s participation meaningful. The lessons learned from this process should guide the next phase of system reform.
A review of adults with disabilities transitioning from their family home to community settings
Authors: Lim Garry
Published: April 2017

INTRODUCTION: This study examined the experiences of adults with disabilities (AWDs) transitioning to community based residential settings. This field of study has not been sufficiently researched despite being a key aspect of adulthood.METHOD: A literature review of articles relating to residential transitions for AWDs was undertaken.FINDINGS: The literature review findings could be grouped around three main categories: AWDs’ perception and self-determination, caregivers’ perceptions of the process and, lastly, the insights from service providers and social policies. The review and feedback identified issues experienced during the residential transition, such as feelings of readiness to transit which relate closely to the person’s self-determination. As the study delved deeper into the residential transition process in Aotearoa New Zealand, AWDs are noted to be vulnerable persons always requiring support in order to develop and maintain their independence.IMPLICATIONS: Substantive state recognition, such as a social compact, is the key groundwork for this marginalised group to develop self-efficacy, have successful transition experiences and sustain good lives. Eventually, this must be in the form of Crown-binding legislation, where vulnerable adults are served through restorative and protective policies.
Tackling child neglect: Research, policy and evidence-based practice
Authors: Gardner Ruth
Published: April 2017

Book reviewed by Liz Langham.
The road to hell: State violence against children in postwar New Zealand
Authors: Stanley Elizabeth
Published: April 2017

Book reviewed by Lesley Pitt.
The social work regulation project in Aotearoa New Zealand
Authors: Hunt Sonya
Published: April 2017

INTRODUCTION: In this second of two articles on the history of professionalisation of social work in Aotearoa New Zealand, consideration is given to the more recent coalescing of forces from the 1990s to the initial implementation of the Social Workers Registration Act (2003), which led to our country’s example of a social work regulation project.APPROACH: This critical consideration of social work regulation in Aotearoa New Zealand situates it within the international social work professionalisation context alongside the national context. Consideration is given to the place of leadership and buy-in from the profession, political sponsorship, cultural considerations, and another ministerial review. Overlaying this, an examination of concepts of public trust, respect, and confidence in professions such as social work, are linked to crises of trust in professions in general, and placed within the current neoliberal, market-driven environment in which this project is anchored.CONCLUSION: The literature serves to document the history of social work regulation in Aotearoa New Zealand and as background for an ongoing research project which aims to uncover interests at work and interrogate the legitimacy of those interests, while enabling the voices of key actors from the time to surface, be explored, and be recorded.
Automatic classification of whistles from coastal dolphins of the southern African subregion
Authors: Erbs Florence , Elwen Simon H. , Gridley Tess
Published: April 2017

Passive acoustic monitoring (PAM) is commonly used to generate information on the distribution, abundance, and behavior of cetacean species. In African waters, the utilization of PAM lags behind most other continents. This study examines whether the whistles of three coastal delphinid species (Delphinus delphis, Tursiops truncatus, and Tursiops aduncus) commonly encountered in the southern African subregion can be readily distinguished using both statistical analysis of standard whistle parameters and the automated detection and classification software PAMGuard. A first account of whistles recorded from D. delphis from South Africa is included. Using PAMGuard, classification to species was high with an overall mean correct classification rate of 87.3%. Although lower, high rates of correct classification were also found (78.4%) when the two T. aduncus populations were included separately. Classification outcomes reflected patterns observed in standard whistle parameters. Such acoustic discrimination may be useful for confirmation of morphologically similar species in the field. Classification success was influenced by training and testing the classifier with data from different populations, highlighting the importance of locally collected acoustic data to inform classifiers. The small number of sampling populations may have inflated the classification success, therefore, classification trials using a greater number of species are recommended.
Robust and efficient Bayesian adaptive psychometric function estimation
Authors: Doire Clement S. J. , Brookes Mike , Naylor Patrick A.
Published: April 2017

The efficient measurement of the threshold and slope of the psychometric function (PF) is an important objective in psychoacoustics. This paper proposes a procedure that combines a Bayesian estimate of the PF with either a look one-ahead or a look two-ahead method of selecting the next stimulus presentation. The procedure differs from previously proposed algorithms in two respects: (i) it does not require the range of possible PF parameters to be specified in advance and (ii) the sequence of probe signal-to-noise ratios optimizes the threshold and slope estimates at a performance level, ϕ, that can be chosen by the experimenter. Simulation results show that the proposed procedure is robust and that the estimates of both threshold and slope have a consistently low bias. Over a wide range of listener PF parameters, the root-mean-square errors after 50 trials were ∼1.2 dB in threshold and 0.14 in log-slope. It was found that the performance differences between the look one-ahead and look two-ahead methods were negligible and that an entropy-based criterion for selecting the next stimulus was preferred to a variance-based criterion.
Thermoviscous effects on sound transmission through a metasurface of hybrid resonances
Authors: Jiang Xue , Li Yong , Zhang Likun
Published: April 2017

This letter analytically and numerically examines sound transmission through a metasurface of hybrid resonances in the presence of thermoviscous dissipation. The metasurface unit of a subwavelength thickness consists of a slit and series of sided resonators embedded in air. Both wall friction and thermoviscous diffusivity in the unit are taken into account. The results reveal that the dissipation has a weak influence on phases even when there is a large loss. The dissipation reduces the transmission by 28% when the thermoviscous boundary layer thickness is only around 2.3% of the slit width. Optimal designs for minimal dissipation are addressed.
Systemic sclerosis is associated with specific alterations in gastrointestinal microbiota in two independent cohorts
Authors: Volkmann Elizabeth R , Hoffmann-Vold Anna-Maria , Chang Yu-Ling , Jacobs Jonathan P , Tillisch Kirsten , Mayer Emeran A , Clements Philip J , Hov Johannes R , Kummen Martin , Midtvedt Øyvind , Lagishetty Venu , Chang Lin , Labus Jennifer S , Molberg Øyvind , Braun Jonathan
Published: April 2017

Objective

To compare faecal microbial composition in patients with systemic sclerosis (SSc) from 2 independent cohorts with controls and to determine whether certain genera are associated with SSc-gastrointestinal tract (GIT) symptoms.

Design

Adult patients with SSc from the University of California, Los Angeles (UCLA) and Oslo University Hospital (OUH) and healthy controls participated in this study (1:1:1). All participants provided stool specimens for 16S rRNA sequencing. Linear discriminant analysis effect size demonstrated genera with differential expression in SSc. Differential expression analysis for sequence count data identified specific genera associated with GIT symptoms as assessed by the GIT 2.0 questionnaire.

Results

The UCLA-SSc and OUH-SSc cohorts were similar in age (52.1 and 60.5 years, respectively), disease duration (median (IQR): 6.6 (2.5–16.4) and 7.0 (1.0–19.2) years, respectively), gender distribution (88% and 71%, respectively), and GIT symptoms (mean (SD) total GIT 2.0 scores of 0.7 (0.6) and 0.6 (0.5), respectively). Principal coordinate analysis illustrated significant microbial community differences between SSc and controls (UCLA: p=0.001; OUH: p=0.002). Patients with SSc had significantly lower levels of commensal genera deemed to protect against inflammation, such asBacteroides(UCLA and OUH),Faecalibacterium(UCLA),Clostridium(OUH); and significantly higher levels of pathobiont genera, such asFusobacterium(UCLA), compared with controls. Increased abundance ofClostridiumwas associated with less severe GIT symptoms in both cohorts.

Conclusions

The present analysis detected specific aberrations in the lower GIT microbiota of patients with SSc from 2 geographically and ethnically distinct cohorts. These findings suggest that GIT dysbiosis may be a pathological feature of the SSc disease state.
Frequency and composition dependency of optical and dielectric properties of PMMA/boehmite nano-hybrid prepared via facile aqueous one-pot process
Authors: Ghamari Misagh , Farzi Gholamali
Published: April 2017

Optical properties of PMMA/boehmite nano-hybrid synthesized directly from their relevant precursors via facile aqueous one-pot process is studied. Silane coupling agent was applied to make compatible chemically the organic–inorganic counterparts. The chemical bond of SiOAl as the main link between organic and inorganic moieties was confirmed by Fourier transforms infrared (FTIR) spectra. The chemical bond of Si–O–Al as the main link between organic and inorganic moieties. Determining the refractive and absorption index, real and imaginary parts of dielectric constant, energy loss function, and their distribution for PMMA/boehmite nano-hybrid as a function of boehmite loading was assessed in the range of 12–120 THz using FTIR data and Kramers–Kronig relations. The inorganic/organic weight ratio varied from 0.7% to 5% and its impact on optical features was evaluated. It was demonstrated that the optical features of hybrids are frequency-dependent and less affected from boehmite incorporation.
Homoclinic Cycle Bifurcations in Planar Maps
Authors: Kamiyama Kyohei , Komuro Motomasa , Aihara Kazuyuki
Published: April 2017

In this study, bifurcations of an invariant closed curve (ICC) generated from a homoclinic connection of a saddle fixed point are analyzed in a planar map. Such bifurcations are called homoclinic cycle (HCC) bifurcations of the saddle fixed point. We examine the HCC bifurcation structure and the properties of the generated ICC. A planar map that can accurately control the stable and unstable manifolds of the saddle fixed point is designed for this analysis and the results indicate that the HCC bifurcation depends upon a product of two eigenvalues of the saddle fixed point, and the generated ICC is a chaotic attractor with a positive Lyapunov exponent.
Dynamic Transition in Symbiotic Evolution Induced by Growth Rate Variation
Authors: Yukalov V. I. , Yukalova E. P. , Sornette D.
Published: April 2017

In a standard bifurcation of a dynamical system, the stationary points (or more generally attractors) change qualitatively when varying a control parameter. Here we describe a novel unusual effect, when the change of a parameter, e.g. a growth rate, does not influence the stationary states, but nevertheless leads to a qualitative change of dynamics. For instance, such a dynamic transition can be between the convergence to a stationary state and a strong increase without stationary states, or between the convergence to one stationary state and that to a different state. This effect is illustrated for a dynamical system describing two symbiotic populations, one of which exhibits a growth rate larger than the other one. We show that, although the stationary states of the dynamical system do not depend on the growth rates, the latter influence the boundary of the basins of attraction. This change of the basins of attraction explains this unusual effect of the qualitative change of dynamics by growth rate variation.
Approximated Spiral and Target Patterns in Bazykin’s Prey–Predator Model: Multiscale Perturbation Analysis
Authors: Banerjee Malay , Ghorai S. , Mukherjee Nayana
Published: April 2017

Spatio-temporal pattern formation has opened up a wide area of research to understand the dynamics between various interacting populations such as a prey and a predator, competing species etc. The governing equations are typically modeled by a reaction–diffusion system. The commonly known patterns, namely, traveling wave, periodic traveling wave, spot, labyrinthine, mixture of spot and stripe, spatio-temporal chaos and interacting spiral chaos can be observed in the spatio-temporal extension of various interacting population models. Apart from these, the other two types of patterns, namely, spiral and target patterns also evolve under suitable parametric conditions near the Turing–Hopf threshold though there is no systematic approach to determine the exact formalism of their emergence. In this paper, we have used a multiscale perturbation analysis to determine these patterns in the spatio-temporal extension of Bazykin’s prey–predator model. An important finding of this work is the use of approximated analytical solution as the initial condition to obtain spiral and target patterns with the help of numerical simulations. Analytical results are general in nature and hence can be used for any spatio-temporal model of interacting population as well as other pattern forming systems which are capable of producing spiral and target patterns.
Discrete Chaotic Systems with One-Line Equilibria and Their Application to Image Encryption
Authors: Chen E. , Min Lequan , Chen Guanrong
Published: April 2017

This paper introduces nine four-dimensional discrete chaotic systems with one-line equilibria (DCSLE), consisting of some simple sine functions. Based on the generalized chaos synchronization (GCS) theorem, a DCSLE is used to construct an eight-dimensional DCSLE GCS system. The new DCSLE GCS system is verified by numerical simulation and then used to design a chaotic pseudorandom number generator (CPRNG). The randomness of ten 100-key streams generated by the CPRNG, two GCS-based CPRNGs, the RC4 PRNG and the ZUC PRNG are tested by the SP800-22/FIPS 140-2 tests. The test results confirm that the randomness performances of the three CPRNGs are promising, for there are no significant correlations between a keystream and any perturbed keystream generated by such CPRNG. Also, the key space of the CPRNG is larger than [Formula: see text]. Finally, the CPRNG is used with an avalanche-effect encryption scheme to encrypt an RGB image, demonstrating that the CPRNG is able to generate the avalanche effects which are similar to those generated by ideal CPRNGs.
Boardroom Brawls: An Empirical Analysis of Disputes Involving Directors
Authors: Agrawal Anup , Chen Mark A.
Published: April 2017

We investigate the internal workings of US corporate governance with a hand-collected dataset of director resignations that are related to power struggles within the board. About two-thirds of the conflicts arise because of how board members interact in carrying out their duties, while most of the remaining cases involve disagreements between directors and top management over corporate strategy or financial policy. Conflicts are more likely to occur at companies where the CEO is the founder or is relatively new to the position. Tensions also increase when there are independent directors with large blockholdings. Stock prices decline sharply on average after a director turnover amid dispute, which may indicate that investors expect the firm to continue to have poor operating performance. The aftermath of such a resignation often includes shareholder class-action lawsuits, proxy contests, asset divestitures, and stock market delistings. Our results highlight the importance of a well-functioning board for reducing agency problems and maximizing shareholder value.
Uniquely Mobile
Authors: Gollakota Shyamnath , Kravets Robin
Published: April 2017

In this edition of GetMobile, we focus on three papers from MobiSys 2014 that embody the goal of enabling new services and using mobile systems in unique ways.
A Low-Cost Wi-Fi-Based Solution for Measuring Human Queues
Authors: Wang Yan , Chen Yingying , Yang Jie , Liul Hongbo , Gruteser Marco , Martin Richard P.
Published: April 2017

Creating devices or systems that can leverage computationally rich environments to support day-to-day interactions between humans and computers is the goal of mobile computing and communication. The increasing use of mobile devices and their data-intensive apps has generated extensive opportunities to monitor and optimize real-world processes through network traffic and corresponding characteristics. For example, research has already shown that we can use cellular call data records and signal traces to understand patterns of large-scale transportation [1] and the level of congestion on roadways [2], respectively. Likewise, ubiquitous wireless infrastructures (e.g., Wi-Fi and Bluetooth) not only provide convenience in communication, but also enable novel applications, such as indoor localization and user authentication. In addition, we have found that the strength of wireless signals from the Wi-Fi traffic consumed by mobile devices can be utilized to perform fine-grained monitoring on a daily common process, i.e., human queues.
How to the Smash Next Billion Mobile App Bugs?
Authors: Chandra Ranveer , Karlsson Börje F. , Lane Nicholas D. , Liang Chieh-Jan Mike , Nath Suman , Padhye Jitu , Ravindranath Lenin , Zhao Feng
Published: April 2017

With users increasingly dependent on their phones, tablets, and wearables, the mobile app ecosystem is more important today than ever before. Creating and distributing apps has never been more accessible. Even single developers can now reach global audiences. But mobile apps must cope with extremely varied and dynamic operating conditions due to factors like diverse device characteristics, wireless network heterogeneity, and varied user behavior. App developers and operators of app marketplaces both lack testing tools that can effectively account for such diversity and, as a result, app failures and performance bugs (like excessive energy consumption) are commonly found today. To address this challenge to mobile app development, we have developed key techniques for scalable automated mobile app testing within two prototype services --- VanarSena and Caiipa. In this paper, we describe our vision for SMASH, a unified cloud-based mobile app testing service that combines the strengths of both previous systems to tackle the complexities presently faced by testers of mobile apps.
Adaptation and Mobility in Wireless Information Systems
Authors: Katz Randy H.
Published: April 2017

About 20 years ago, I wrote "Adaptation and Mobility in Wireless Information Systems" for the very first issue of theIEEE Personal Communications Magazine[1]. From today's perspective, with our experience of smartphones, pervasive Wi-Fi and LTE wireless Internet access, and "video to your palm," it is difficult to conceive of the primitive state of wireless and mobile systems of that time.
Tango
Authors: Gordon Mark S. , Hong David Ke , Chen Peter M. , Flinn Jason , Mahlke Scott , Mao Zhuoqing Morley
Published: April 2017

Mobile devices have less computational power and poorer Internet connections than other computers. Computation offload [1, 2, 3, 4], in which some portions of an application are migrated to a server, has been proposed as one way to remedy this deficiency. Yet, partitionbased offload is challenging because it requires applications to accurately predict whether mobile or remote computation will be faster, and it requires that the computation be large enough to overcome the cost of shipping state to and from the server. Further, offload does not currently benefit network-intensive applications.
Battery Fundamentals
Authors: Ferrese Anthony
Published: April 2017

The use of batteries as a portable power source has gained tremendous importance for powering mobile devices and for enabling greener and less energy-intensive transportation. Whether the demand is for a smart phone, laptop, tablet or the next wearable, the consumer demands a thinner and lighter battery while maintaining or increasing battery life at the lowest possible cost. This demand has caused many companies to increasingly consider the battery and its performance when designing their next device. While, in the past, it may have been acceptable to take an "off-the-shelf" battery that meets specifications and "plug it in", many companies are starting to implement "smart" designs that take into account specific battery chemistries and characteristics to improve overall performance. This requires a knowledge of how a battery works. With this in mind, this article gives an explanation of battery fundamentals, why batteries degrade over their life, what limits their performance, the trade-offs between high power and high energy, and current efforts to build a better battery. While many of the overall properties are similar for many battery chemistries, here we will focus on the lithium-ion battery, specifically the cobaltdioxide/ graphite lithium-ion battery, one of the most popular battery chemistries for mobile devices.
THE ANATOMY OF SMARTPHONE UNLOCKING
Authors: Malkin Nathan , Harbach Marian , De Luca Alexander , Egelman Serge
Published: April 2017

To prevent unauthorized access to their smartphones, users can enable a "lock screen," which may require entering a PIN or password, drawing a pattern, or providing a biometric. We present the results of two studies that together offer a detailed analysis of the smartphone locking mechanisms currently available to billions of smartphone users worldwide. An online survey (N=8,286), conducted in eight different countries, sheds light on people's reasons for choosing their screen lock method and demonstrates significant crosscultural differences in attitudes towards this subject. In a separate monthlong field study (N=134), we studied how existing lock screen mechanisms provide users with distinct tradeoffs between usability and security, identifying areas where both could be improved.
Delirium and High Creatine Kinase and Myoglobin Levels Related to Synthetic Cannabinoid Withdrawal
Authors: Yazici Ahmet Bulent , Yazici Esra , Erol Atila
Published: April 2017

Synthetic cannabinoids (SCs) are included in a group of drugs called new psychoactive substances. Effects of SCs on the central nervous system are similar to other cannabinoids, but 2–100 times more potent than marijuana. Thus, addiction and withdrawal symptoms are more severe than natural cannabinoids. Withdrawal symptoms of SCs were reported in the literature previously. But there is no report about SC withdrawal delirium and its treatment. Several studies reported that agonists of CB1 receptors play a role in GABA and glutamatergic neurotransmission, which is similar to the effects of alcohol on GABA and glutamatergic receptors. Previous studies on alcohol delirium cases suggested that elevated creatine kinase (CK) can be a marker of progress. This study reports delirium and high serum CK levels related to SC withdrawal and offers a treatment with benzodiazepine for them. We described two cases treated in our inpatient clinic about SC withdrawal with increase of serum CK level and other laboratory parameters. One of them demonstrated delirium symptoms and the other did not with early rapid treatment.
Acoustic Emission Characteristics of Compressive Deformation and Failure of Siltstone under Different Water Contents
Authors: Chen Lei , Zhao Jian , Zheng Zhiyang
Published: April 2017

The uniaxial compression and acoustic emission (AE) monitoring of siltstone specimens in the Gongchangling open-pit iron mine in Liaoning Province was conducted by evaluating the effects of three water saturation levels: dry, natural, and water-saturated. The siltstone AE characteristics were analyzed according to water content; the relationship between the AE characteristics and the growth and expansion of siltstone cracks was subsequently discussed. Research results indicated the following: siltstone specimens had distinctly different mechanical properties and AE characteristics according to water content; as the water content increased the compressive strength and elasticity modulus of specimens decreased. In the compacting phase of specimens under compression, the AE count rate of the water-saturated specimen was relatively small and the events were relatively stable. In the linear-elastic deformation phase, the AE count rate of the dry specimen increased sharply, reaching approximately 400 times/s. In the plastic yield deformation phase, the peak value of the AE count rate of the dry specimen ranged between 955 and 1,068 times/s, whereas that of the water-saturated specimen only attained a range of 635 to 782 times/s. In the failure phase, the time to reach the peak stress value of the dry specimen was increased as compared to that of the AE count rate.
Electroacupuncture Improves Cognitive Deficits through Increasing Regional Cerebral Blood Flow and Alleviating Inflammation in CCI Rats
Authors: Han Dexiong , Liu Zhe , Wang Gaimei , Zhang Ying , Wu Zemin
Published: April 2017

Objective. To investigate the effect of EA on regional cerebral blood flow, cognitive deficits, inflammation, and its probable mechanisms in chronic cerebral ischemia (CCI) rats. Methods. Rats were assigned randomly into sham operation group (sham group) and operation group. For operation group, CCI model was performed using the permanent bilateral common carotid artery occlusion (BCCAO) method, and then rats were further randomly divided into model group and electroacupuncture (EA) group. 2/15 Hz low‐frequency pulse electric intervention was applied at “Baihui” and “Dazhui” acupoints in EA group. Four weeks later, Morris water maze test was adopted to assess the cognitive function, using laser Doppler flowmetry to test changes of regional cerebral blood flow (rCBF); double antibody sandwich enzyme‐linked immunosorbent assay (DAS‐ELISA) to measure proinflammatory cytokines (IL‐6, TNF‐α, and IL‐1β); western blot to test the protein expression quantities of proinflammatory cytokines, JAK2, and STAT3; and RT‐PCR to test JAK2 mRNA and STAT3 mRNA in the hippocampus in each group. Results. Compared with the model group, learning and memory abilities and rCBF and IL‐6 expression of the EA group enhanced markedly; IL‐1β and JAK2 significantly decreased; TNF‐α and STAT3 also declined, but the difference was not apparent. Conclusion. Our research suggests that EA can improve cognitive deficits which may be induced by increasing rCBF and anti‐inflammatory effect.
The Spreading Residue Harmonic Balance Method for Strongly Nonlinear Vibrations of a Restrained Cantilever Beam
Authors: Qian Y. H. , Pan J. L. , Chen S. P. , Yao M. H.
Published: April 2017

The exact solutions of the nonlinear vibration systems are extremely complicated to be received, so it is crucial to analyze their approximate solutions. This paper employs the spreading residue harmonic balance method (SRHBM) to derive analytical approximate solutions for the fifth-order nonlinear problem, which corresponds to the strongly nonlinear vibration of an elastically restrained beam with a lumped mass. When the SRHBM is used, the residual terms are added to improve the accuracy of approximate solutions. Illustrative examples are provided along with verifying the accuracy of the present method and are compared with the HAM solutions, the EBM solutions, and exact solutions in tables. At the same time, the phase diagrams and time history curves are drawn by the mathematical software. Through analysis and discussion, the results obtained here demonstrate that the SRHBM is an effective and robust technique for nonlinear dynamical systems. In addition, the SRHBM can be widely applied to a variety of nonlinear dynamic systems.
Neimark-Sacker Bifurcation and Chaos Control in a Fractional-Order Plant-Herbivore Model
Authors: Din Qamar , Elsadany A. A. , Khalil Hammad
Published: April 2017

This work is related to dynamics of a discrete-time 3-dimensional plant-herbivore model. We investigate existence and uniqueness of positive equilibrium and parametric conditions for local asymptotic stability of positive equilibrium point of this model. Moreover, it is also proved that the system undergoes Neimark-Sacker bifurcation for positive equilibrium with the help of an explicit criterion for Neimark-Sacker bifurcation. The chaos control in the model is discussed through implementation of two feedback control strategies, that is, pole-placement technique and hybrid control methodology. Finally, numerical simulations are provided to illustrate theoretical results. These results of numerical simulations demonstrate chaotic long-term behavior over a broad range of parameters. The computation of the maximum Lyapunov exponents confirms the presence of chaotic behavior in the model.
High-Sensitive C-Reactive Protein Levels in a Group of Syrian University Male Students and Its Associations with Smoking, Physical Activity, Anthropometric Measurements, and Some Hematologic Inflammation Biomarkers
Authors: Zarzour Wafika , Dehneh Nada , Rajab Mazen
Published: April 2017

In Syria, health risk data on young males are limited. Hence, the aim of the present study was to evaluate cardiovascular disease (CVD) risk factors along with C-reactive protein levels measured by high-sensitive method (hsCRP) in a group of healthy males of university students (n=101, 18–25 years old). Participants’ anthropometric characteristics; alcohol drinking, smoking, and physical activity habits; parents medical history; and some inflammatory biomarkers were inspected for their associations with hsCRP.Results. Regarding hsCRP level, 19 participants were at average (1–3 mg/L) and 13 were at high (>3 mg/L) risk of CVD. Nonparametric statistical tests (pvalue < 0.05) revealed that hsCRP level was higher in participants who had high body mass index (BMI), had high BMI with high waist-to-hip ratio (WHR), or did not practice sport frequently. Unexpectedly, it did not vary between smokers and nonsmokers. In general, it correlated positively with anthropometric and erythrocyte sedimentation rate (ESR) measurements. Nevertheless, it negatively correlated with sports practicing in overall and nonsmoker groups and in participants whose parents were without medical history. Finally, when participants with high BMI were smokers, did not practice sport frequently, or had a parent with medical history, their hsCRP levels were higher than others who had the same circumstances but with low BMI.
Resistivity and AE Response Characteristics in the Failure Process of CGB under Uniaxial Loading
Authors: Qi Tingye , Feng Guorui
Published: April 2017

To understand the characteristics of the acoustic emission (AE) and electrical resistivity of cemented coal gangue backfill (CGB) under uniaxial compression, the variations in these characteristics at 1 day, 3 days, and 7 days are analyzed by means of a stress-strain-resistivity-AE test, and the microperformances are investigated. The research results indicate that the AE can reflect the initiation and propagation of cracks and later explain the variation of the resistivity of the specimens under the uniaxial loading. The cumulative energy curve of AE is approximately two straight lines corresponding to the peak stress, and the difference in the linear slope gradually decreased with the increasing curing time due to the lower pore solution content and the compact pore structure. The relationships between the stress and resistivity and the loading condition before and after the peak stress at different curing times were established. Therefore, it is of great significance to predict the stability of the filling body by monitoring the AE and resistivity variations of the filling body. In addition, it is possible to calculate the roof stress using the relation equation between the resistivity and stress.
Incident Light Frequency‐Based Image Defogging Algorithm
Authors: Zhang Wenbo , Hou Xiaorong
Published: April 2017

To solve the color distortion problem produced by the dark channel prior algorithm, an improved method for calculating transmittance of all channels, respectively, was proposed in this paper. Based on the Beer‐Lambert Law, the influence between the frequency of the incident light and the transmittance was analyzed, and the ratios between each channel’s transmittance were derived. Then, in order to increase efficiency, the input image was resized to a smaller size before acquiring the refined transmittance which will be resized to the same size of original image. Finally, all the transmittances were obtained with the help of the proportion between each color channel, and then they were used to restore the defogging image. Experiments suggest that the improved algorithm can produce a much more natural result image in comparison with original algorithm, which means the problem of high color saturation was eliminated. What is more, the improved algorithm speeds up by four to nine times compared to the original algorithm.