bluuebunny/crossref_metadata_2025 huggingface dataset:
Refilling temporary ponds has timing‐dependent effects on Hyla gratiosa performance
Authors: Pintar Matthew R. , Resetarits William J.
Published: September 2018

Disturbances and variation in abiotic habitat conditions greatly affect populations and communities. The multitude of processes that occur in natural systems offers the possibility that the trajectories of ephemeral habitats and the effects of disturbances can be slowed or reversed. Hydroperiod is a defining characteristic in freshwater systems, with temporary ponds supporting distinct communities of organisms with plastic developmental trajectories and complex lifecycles that allow them to cope with the vagaries of pond duration.

Despite work on the effects of pond drying on aquatic animals, little consideration has been given to filling, which can extend the duration of small, drying ponds. Our goal was to assess how increasing the volume of small ponds affects the developmental trajectories of larval amphibians living in these habitats. We conducted a field mesocosm experiment to assess how filling of ponds early, midway and late in the larval period affected the survival and development of the barking treefrog, Hyla gratiosa. We hypothesised that filling early in the larval stage would provide the most benefits, producing more and larger metamorphs than filling later in development.

We found that through various effects on survival, metamorphosis, habitat quality and competition, increasing volume early in development produced more and larger metamorphs with faster growth rates than any other treatment, whereas filling late in development produced few, small, slow growing metamorphs.

Our results provide support for the role of stressors in initiating metamorphosis and also show that increased pond volumes early in larval development can provide benefits to Hyla populations in terms of compensatory growth, but filling late in development has little benefit.
Influence of bioenergy crops on pollinator activity varies with crop type and distance
Authors: Berkley Nicholas A. J. , Hanley Mick E. , Boden Rich , Owen Robyn S. , Holmes Jordan H. , Critchley Russell D. , Carroll Kathryn , Sawyer Daniel G. M. , Parmesan Camille
Published: September 2018

Compared to traditional arable crops, second‐generation perennial energy crops (PECs) are generally associated with increased biodiversity and ecosystem services, but robust experimental studies on this subject are few. Consequently, the potential for PEC cultivation to contribute to enhanced pollination processes in adjacent farmland remains unclear. In a 4‐year field study across multiple sites and two PECs (Miscanthus x giganteusand willow short‐rotation coppice), we examine whether pollinator visits to crop margin wildflowers were augmented by PEC cultivation. Each field was paired with two cereal fields, one adjacent to the PEC and one distant, and we recorded wildflower visits to crop margins by three pollinator groups: hoverflies, bumblebees and butterflies/moths. We also quantified floral resources, since crop‐specific management seemed a likely means of influencing margin wildflowers and thus pollinator activity. Our results add quantitative support to the suggestion that PECs should enhance ecosystem processes in agri‐landscapes. However, benefits were highly context‐dependent. Consistent enhancement of pollinator activity in margins of PEC fields was only apparent for willow where the relative frequency of flower visitation was higher for all three pollinator groups compared to adjacent or distant cereals. This distribution was most likely positively associated with the increased availability of preferred food plants in willow margins. InMiscanthus, by contrast, opposing trends arose for different pollinator taxa: Lepidoptera were the only pollinator group more frequently associated with PEC margins; bumblebees showed no variation while hoverflies were comparatively more abundant in distant cereal margins than in other crop types. Future land‐use practices should consider how PEC identity affects both target species and ecosystem processes. Tackling anthropogenic climate change through cultivation of willow, in particular, may yield local conservation benefits for both wildflowers and pollinators, although strategic cultivation of PECs to enhance pollination processes in the wider agri‐environment may not be achievable.
Vascular architecture in the bacteriogenic light organ of Euprymna tasmanica (Cephalopoda: Sepiolidae)
Authors: Patelunas Anthony J. , Nishiguchi Michele K.
Published: September 2018

Symbiosis between southern dumpling squid, Euprymna tasmanica (Cephalopoda: Sepiolidae), and its luminescent symbiont, the bacterium Vibrio fischeri, provides an experimentally tractable system to examine interactions between the eukaryotic host and its bacterial partner. Luminescence emitted by the symbiotic bacteria provides light for the squid in a behavior termed “counter‐illumination,” which allows the squid to mask its shadow amidst downwelling moonlight. Although this association is beneficial, light generated from the bacteria requires large quantities of oxygen to maintain this energy‐consuming reaction. Therefore, we examined the vascular network within the light organ of juveniles of E. tasmanica with and without V. fischeri. Vessel type, diameter, and location of vessels were measured. Although differences between symbiotic and aposymbiotic squid demonstrated that the presence of V. fischeri does not significantly influence the extent of vascular branching at early stages of symbiotic development, these finding do provide an atlas of blood vessel distribution in the organ. Thus, these results provide a framework to understand how beneficial bacteria influence the development of a eukaryotic closed vascular network and provide insight to the evolutionary developmental dynamics that form during mutualistic interactions.
RFLP analysis of flagellin (Fla) gene of Campylobacter jejuni from ovines of Kashmir, India
Authors: Bisma Gull , Sabia Qureshi , Amin Kashoo Zahid , Ahmad Wani Shakil , Nabi Magray Suhail , Ahmad Malik Firdose , Isfaqul Hussain M. , Aasim Habib , Ali Rather Mudasir , Shafkat Majeed Khan , Rafia Maqbool , Shafi Shah Muneeba
Published: September 2018

Campylobacteriosis caused by Campylobacter jejuni is the most frequently reported foodborne illness transmitted directly or indirectly between animals and humans. Humans can be infected after ingesting undercooked poultry and other meats, raw milk, raw clams, contaminated foodstuffs etc. In the present study sheep breeding farms of Kashmir valley were screened for presence of Campylobacter jejuni, and C. coli. infection. Of the 200 samples comprising of vaginal swabs and aborted material 25(12.5%) isolates were found to be positive for Campylobacter genus, 17 (8.5%) isolates were positive for C. jejuni and 3(1.5%) for C. coli. C. jejuni and C. coli were found to harbour virulence genes like fla, cdt and cad. Amplified flagellin gene (855 bp) of all C. jujeni isolates on digestion with DdeI yielded ∼700 bp and ∼155 bp products indicating no genetic variability among isolates. The flagellin gene sequence was deposited in GenBank under accession no MG417049.

Practical applications

The present study aimed to screen the sheep farms of Kashmir for presence of C. jejuni and C. coli infection. Food safety is of importance to the consumer, the food industry, and the economy. Campylobacter spp. and Salmonella spp. are the leading causes of bacterial foodborne illness and are considered as major public health concern. The major routes of transmission in humans are contaminated or undercooked meat, unpasteurized milk or dairy products, and untreated water. Screening of sheep for Campylobacteriosis in the present study is a part of work aiming to suggest control measures and intervention strategies, to minimize the occurrence of Campylobacter spp. in sheep and poultry flocks of the state in particular and country in general. This would reduce the quantitative Campylobacter burden in animals and foods thereby reduce the pathogen risk to humans.
Determination of quality parameters of gilthead sea bream (Sparus aurata) fillets coated with electrospun nanofibers
Authors: Ceylan Zafer , Unal Sengor Gulgun F. , Basahel Abdulrahman , Yilmaz Mustafa Tahsin
Published: September 2018

The changes in texture, color, and odor parameters of the samples (C: uncoated samples, CN: the group coated with chitosan‐based nanofibers, TLCN: the samples coated with thymol‐loaded chitosan‐based electrospun nanofibers) were tested. The changes in color of the groups were defined by using L* (lightness), a* (red/green), and b* (blue/yellow) parameters for pH values of C, CN, and TLCN. In terms of microbial spoilage, psychrophilic bacteria counts (TPBc) of the samples were revealed during storage period. The results of microbiological, sensory, and psychochemical analysis demonstrated that CN and TLCN were both effective against rapid deterioration, exhibiting up to 100% limitation of deterioration; furthermore, TLCN was more effective than that of CN samples. The study results suggested that coating of gilthead sea bream fillets with CN and TLCN would be a promising approach to delay the rapid deterioration in sensory properties (odor, texture, and color) and the delay bacteria growth. Also, the rapid changes in the physicochemical quality parameters (pH, L*, a*, and b*) of fish fillets were controlled by using electrospun nanofiber coating technique.

Practical applications

Coating of the fish fillets with chitosan‐based nanofibers delayed the deterioration. Thymol‐loaded chitosan‐based nanofibers were more effective to delay the deterioration. Applied tests revealed almost 100% difference between groups.
The Implementation of Functional Family Therapy (FFT) as an Intervention for Youth Probationers in Singapore
Authors: Gan Daniel Z. Q. , Zhou Yiwei , Hoo Eric , Chong Dominic , Chu Chi Meng
Published: September 2018

Family functioning is predictive of youth recidivism in Singapore. However, there is a lack of family based interventions for youth offenders on community probation. Evidence‐based family interventions developed in Western populations, such as Functional Family Therapy (FFT), have been found to be effective in mitigating subsequent youth criminal behavior. However, no study has examined whether such interventions can be implemented and adapted for use in Eastern cultures. Thus, this paper sought to detail the implementation of FFT in Singapore. Rationale for the adoption of FFT is discussed, and key activities undertaken during the first 18 months of implementation are described. Preliminary data suggest that initial implementation efforts were successful. Challenges encountered, and implications in relation to the broader literature are discussed.
The efficacy of coronary sinus reducer in patients with refractory angina—A systematic review of the literature
Authors: Bazoukis George , Brilakis Emmanouil S. , Tse Gary , Letsas Konstantinos P. , Kitsoulis Panagiotis , Liu Tong , Baranchuk Adrian , Sideris Antonios , Tsioufis Costas , Stavrakis Stavros
Published: September 2018

Objectives

The aim of our systematic review was to investigate the efficacy of coronary sinus (CS) reducer device in patients with refractory angina.

Background

The CS reducer device provides a therapeutic option for patients with coronary artery disease who are not suitable for revascularization.

Methods

Two independent investigators (GB and GT) systematically searched the Medline and Cochrane library databases for studies describing the efficacy and safety of the CS reducer in patients with refractory angina from January 1, 2000 until May 12, 2018 using the following terms: “coronary sinus (reducer OR reducing) device.” Efficacy was defined as ≥1 unit improvement in the Canadian cardiovascular society (CCS) score.

Results

Our search strategy provided six studies (five observational studies and one randomized clinical trial) with 196 patients. The CS reducer device was effective in 146/186 (78.5%) patients. CCS score improved from 3.2 at baseline to 1.9 after 8.6 months of follow‐up. The efficacy of CS reducer device was also demonstrated as an improvement in Seattle Angina Questionnaire score, dobutamine echocardiography, thalium single‐photon emission computed tomography perfusion studies, 6‐min‐walk test and myocardial perfusion reserve index. Implantation failed in 4 of 196 (2%) patients and 5 patients (2.5%) had a complication during 30‐day follow‐up.

Conclusions

The CS reducer is a promising treatment option for patients with refractory angina who are not candidates for revascularization. However, larger randomized control trials with long‐term follow‐up are needed to elucidate its role.
A new complimentary web‐based tool for manual analysis of microcirculation videos: Validation of the Capillary Mapper against the current gold standard AVA 3.2
Authors: Hessler Michael , Arnemann Philip‐Helge , Zamit Frédéric , Seidel Laura , Kampmeier Tim‐Gerald , Kathöfer Ulrich , Morelli Andrea , Ince Can , Rehberg Sebastian W. , Ertmer Christian
Published: September 2018

Objective

The aim of the current study was to compare a newly developed web‐based freely accessible software program for manual analysis of the microcirculation, the Capillary Mapper (CM), with AVA 3.2 software (AVA; MicroVision Medical B.V., Amsterdam, The Netherlands), which is the current gold standard for analysis of microcirculation videos.

Methods

A web‐based software program was developed, which enables manual analysis of videos of the microcirculation to be carried out according to recommendations of the 2018 consensus conference. A set of 50 high quality microcirculation videos was analyzed with AVA and CM with respect to total vessel density, perfused vessel density, proportion of perfused vessels, and the microvascular flow index.

Results

Comparison of the mean values derived from manual analysis with CM and AVA revealed no significant differences in microcirculatory variables. Analysis according to Bland and Altman revealed an acceptable bias between manual analysis with the CM and AVA for all variables tested with sufficient limits of agreement. The analysis of intraclass correlation showed “excellent” agreement for all microcirculatory variables analyzed.

Conclusions

The newly developed CM was successfully validated for manual analyses of microcirculation videos against the current gold standard, the software AVA 3.2.
Global changes alter plant multi‐element stoichiometric coupling
Authors: Tian Dashuan , Reich Peter B. , Chen Han Y. H. , Xiang Yangzhou , Luo Yiqi , Shen Ying , Meng Cheng , Han Wenxuan , Niu Shuli
Published: September 2018

Plant stoichiometric coupling among all elements is fundamental to maintaining growth‐related ecosystem functions. However, our understanding of nutrient balance in response to global changes remains greatly limited to plant carbon : nitrogen : phosphorus (C : N : P) coupling.

Here we evaluated nine element stoichiometric variations with one meta‐analysis of 112 global change experiments conducted across global terrestrial ecosystems and one synthesis over 1900 species observations along natural environment gradients across China.

We found that experimentally increased soil N and P respectively enhanced plant N : potassium (K), N : calcium (Ca) and N : magnesium (Mg), and P : K, P : Ca and P : Mg, and natural increases in soil N and P resulted in qualitatively similar responses. The ratios of N and P to base cations decreased both under experimental warming and with naturally increasing temperature. With decreasing precipitation, these ratios increased in experiments but decreased under natural environments. Based on these results, we propose a new stoichiometric framework in which all plant element contents and their coupling are not only affected by soil nutrient availability, but also by plant nutrient demand to maintain diverse functions under climate change.

This study offers new insights into understanding plant stoichiometric variations across a full set of mineral elements under global changes.
A case of bidirectional conduction block within the superior vena cava induced by cryoballoon pulmonary vein isolation
Authors: Watanabe Tomonori , Hachiya Hitoshi , Igarashi Miyako , Kusa Shigeki , Iesaka Yoshito
Published: September 2018

A 53‐year‐old male underwent a pulmonary vein isolation (PVI) of atrial fibrillation (AF) with a second‐generation cryoballoon (CB). Although the patient maintained sinus rhythm after the PVI, a superior vena cava (SVC) fibrillation was recorded by a circular‐multipolar‐electrode catheter positioned inside the SVC that suggested conduction block between the right atrium (RA)‐SVC connection. An adenosine triphosphate intravenous injection induced a dormant reconnection of the SVC myocardial sleeve and converted sinus rhythm to an AF rhythm. This case demonstrated that a CB application for the isolation of a right superior pulmonary vein could induce an electrical conduction block between the RA‐SVC connection.
SOLVING THE PROBLEM OF LOGICAL OMNISCIENCE
Authors: Dogramaci Sinan
Published: September 2018

This paper looks at three ways of addressing probabilism's implausible requirement of logical omniscience. The first and most common strategy says it's okay to require an ideally rational person to be logically omniscient. I argue that this view is indefensible on any interpretation of ‘ideally rational’. The second strategy says probabilism should be formulated not in terms of logically possible worlds but in terms of doxastically possible worlds, ways you think the world might be. I argue that, on the interpretation of this approach that lifts the requirement of certainty in all logical truths, the view becomes vacuous, issuing no requirements on rational believers at all. Finally, I develop and endorse a new solution to the problem. This view proposes dynamic norms for reasoning with credences. The solution is based on an old proposal of Ian Hacking's that says you're required to be sensitive to logical facts only when you know they are logical facts.
Synthesis, Characterization and Photobiological Studies of Ru(II) Dyads Derived from α‐Oligothiophene Derivatives of 1,10‐Phenanthroline
Authors: Monro Susan , Cameron Colin G. , Zhu Xiaolin , Colón Katsuya L. , Yin Huimin , Sainuddin Tariq , Hetu Marc , Pinto Mitch , Fuller Anderson , Bennett Leah , Roque John , Sun Wenfang , McFarland Sherri A.
Published: September 2018

Three new bis(2,2′‐bipyridine)‐heteroleptic Ru(II) dyads incorporating thienyl groups (n = 1–3, compounds 1, 2 and 3, respectively) appended to 1,10‐phenanthroline were synthesized and characterized to investigate the impact of n on the photophysical and photobiological properties within the series. All three complexes showed unstructured emission near 618 nm from a triplet metal‐to‐ligand charge transfer (3MLCT) state with a lifetime (τem) of approximately 1 μs. Transient absorption measurements revealed an additional excited state that was nonemissive and long‐lived (τTA = 43 μs for 2 and 27 μs for 3), assigned as a triplet intraligand (3IL) state that was accessible only in 2 and 3. All three complexes were strong singlet oxygen (1O2) sensitizers, with quantum yields (Φ∆) for 2 and 3 being the largest (74–78%), and all three were photocytotoxic to cancer cells with visible light activation in the order: 3 > 2 > 1. Cell‐free DNA photodamage followed the same trend, where potency increased with decreasing 3IL energy. Compounds 2 and 3 also showed in vitro photobiological effects with red light (625 nm), where their molar absorptivities were <100 m−1 cm−1. These findings highlight that Ru(II) dyads derived from α‐oligothiophenes directly appended to 1,10‐phenanthroline—namely 2 and 3—possess low‐lying 3IL states that are highly photosensitizing, and they may therefore be of interest for photobiological applications such as photodynamic therapy (PDT).
The Effect of Sourcing Policies on Suppliers’ Sustainable Practices
Authors: Agrawal Vishal , Lee Deishin
Published: September 2018

To meet the growing demand for sustainably produced products, firms must be able to source sustainably produced parts from their suppliers. In this study, we analyze how a buyer (manufacturer or retailer) can use sourcing policies to influence their suppliers to adopt sustainable processes that can meet certain sustainability criteria. We study two sustainable sourcing policies commonly observed in practice, which influence suppliers’ process decisions by committing to offer sustainable products. Under a Sustainable Preferred policy, a buyer commits to offering a sustainable product if she can source sustainably produced parts from the supplier, but will otherwise offer a conventional product. In contrast, under a Sustainable Required sourcing policy, a buyer will only offer a sustainable product, and therefore will only source from the supplier if he has adopted a sustainable process. Our results offer insights for managers by identifying how these sustainable sourcing policies influence upstream suppliers to switch to a sustainable process, and how this affects the ability of a downstream buyer to offer a sustainable product. We find that when the buyer sources from a sole supplier, the Preferred policy can deter the supplier from switching as compared to when the buyer remains noncommittal. However, only the Required policy can induce the supplier to switch. In contrast, when a buyer has multiple suppliers, the Preferred policy does not deter the supplier, but can induce him to switch to a sustainable process, similar to the Required policy. Accordingly, our results suggest that to induce the supplier to switch to a sustainable process, a buyer should adopt a Required policy when sourcing from a sole supplier, but utilize a Preferred policy when there are multiple suppliers.
Conceptual Flutter Analysis of Labyrinth Seals Using Analytical Models—Part II: Physical Interpretation
Authors: Vega Almudena , Corral Roque
Published: September 2018

The dimensionless model presented in part I of the corresponding paper to describe the flutter onset of two-fin rotating seals is exploited to extract valuable engineering trends with the design parameters. The analytical expression for the nondimensional work-per-cycle depends on three dimensionless parameters of which two of them are new. These parameters are simple but interrelate the effect of the pressure ratio, the height, and length of the interfin geometry, the seal clearance, the nodal diameter (ND), the fluid swirl velocity, the vibration frequency, and the torsion center location in a compact and intricate manner. It is shown that nonrelated physical parameters can actually have an equivalent impact on seal stability. It is concluded that the pressure ratio can be stabilizing or destabilizing depending on the case, whereas the swirl of the flow is always destabilizing. Finally, a simple method to extend the model to multiple interfin cavities, neglecting the unsteady interaction among them, is described.
Four-Quadrant Analysis and System Design for Single-Rod Hydrostatic Actuators
Authors: Costa Gustavo Koury , Sepehri Nariman
Published: September 2018

In this paper, we present a novel design for single-rod hydrostatic actuators that produces a stable response in all operation quadrants. The new design, which can have different embodiments, is built upon compensating for the differential flows coming in and out of single-rod actuators, by alternately connecting cap and rod sides of the cylinder to a flow source in accordance with the energy flow direction between the circuit and the load. We show that previous quadrant division definitions result in either geometric quadrants that do not coincide with motoring and pumping operation, or misrepresentations of the actual energy exchange between the load and the cylinder. The proposed quadrant representation gives the exact information about the right operation of compensating flow valves. The efficacy of the new design has been tested on an instrumented John Deere JD-48 backhoe. Precise redirection of the compensation flow allowed for nonoscillatory motions in all quadrants of operation and various loading conditions.
Experimental and Numerical Investigation on Flow Characteristics of Large Cross-Sectional Ionic Wind Pump With Multiple Needles-to-Mesh Electrode
Authors: Zhang J. F. , Wang S. , Zeng M. J. , Qu Z. G.
Published: September 2018

Ionic wind pumps have attracted considerable interest because of their low energy consumption, compact structures, flexible designs, and lack of moving parts. However, large cross-sectional ionic wind pumps have yet to be numerically analyzed and experimentally optimized. Accordingly, this study develops a large cross-sectional ionic wind pump with multiple needles-to-mesh electrode, as well as analyzes its flow characteristics using a proposed full three-dimensional simulation method validated with experimental data. To obtain a considerably high outlet average velocity, experimental studies and numerical methods are employed to optimize the pump's configuration parameters, including needle electrode configuration, needle diameter, grid size, and gap between electrodes. The breakdown voltage and highest velocity corresponding to the breakdown voltage increase with an increase in the needle tip-to-mesh gap. After parametric optimization, a maximum velocity of 2.55 m/s and a flow rate of 2868 L/min are achieved.
ZnO flexible high voltage thin film transistors for power management in wearable electronics
Authors: Hong Wen-Chiang , Zhang Yonghui , Wang Szu-Ying , Li Yuxuan , Alim Navila , Du Xiaolong , Mei Zengxia , Lu Yicheng
Published: September 2018

A ZnO-based flexible high voltage thin film transistor (f-HVTFT) is fabricated on a plastic substrate. The f-HVTFT shows a blocking voltage of 150 V, on-current of 170 μA, and off-current of 0.01 pA at a drain bias of 10 V. The maximum recoverable bending radius of the device reaches 11 mm, and the blocking voltage is larger than 120 V while it is under bending. The unique center-symmetric circular structure of the f-HVTFT is particularly useful to the wearable systems, which enable one to operate under bending from arbitrary directions. The ZnO-based f-HVTFT is a promising candidate to be used for power management of self-powered wearable electronic systems.
Effect of proton irradiation energy on SiNx/AlGaN/GaN metal-insulator semiconductor high electron mobility transistors
Authors: Fares Chaker , Ren Fan , Pearton Stephen J. , Yang Gwangseok , Kim Jihyun , Lo Chien-Fong , Johnson J. Wayne
Published: September 2018

The effects of proton irradiation energy on the electrical properties of SiNx/AlGaN/GaN metal-insulator semiconductor high electron mobility transistors (MISHEMTs) using in situ grown silicon nitride as the gate dielectric were studied. The SiNx/AlGaN/GaN MISHEMT devices were irradiated with protons at energies of 5, 10, or 15 MeV at a fixed fluence of 2.5 × 1014 cm−2. The largest amount of device degradation was shown in the samples irradiated with the lowest irradiation energy of 5 MeV. The DC saturation current was reduced by 10.4%, 3.2%, and 0.5% for MISHEMTs irradiated with proton energies of 5, 10, and 15 MeV, respectively. Device performance degradation was more pronounced in the irradiated samples under high-frequency operation. At a frequency of 100 kHz, the percent saturation drain current reduction at a gate voltage of 3 V was 40%, 19%, and 17% after proton irradiation at 5, 10, and 15 MeV, respectively. The carrier removal rates for the MISHEMT devices were in the range of 21–144 cm−1 for the proton irradiation energies studied. The measured DC degradation and carrier removal rates are lower than the values reported for AlGaN/GaN metal-gate high electron mobility transistor devices irradiated at similar conditions, which can be attributed to the SiNx insulating layer reducing the total damage on the AlGaN surface.
Vocal instabilities in a three-dimensional body-cover phonation model
Authors: Zhang Zhaoyan
Published: September 2018

The goal of this study is to identify vocal fold conditions that produce irregular vocal fold vibration and the underlying physical mechanisms. Using a three-dimensional computational model of phonation, parametric simulations are performed with co-variations in vocal fold geometry, stiffness, and vocal tract shape. For each simulation, the cycle-to-cycle variations in the amplitude and period of the glottal area function are calculated, based on which the voice is classified into three types corresponding to regular, quasi-steady or subharmonic, and chaotic phonation. The results show that vocal folds with a large medial surface vertical thickness and low transverse stiffness are more likely to exhibit irregular vocal fold vibration when tightly approximated and subject to high subglottal pressure. Transition from regular vocal fold vibration to vocal instabilities is often accompanied by energy redistribution among the first few vocal fold eigenmodes, presumably due to nonlinear interaction between eigenmodes during vocal fold contact. The presence of a vocal tract may suppress such contact-related vocal instabilities, but also induce new instabilities, particularly for less constricted vocal fold conditions, almost doubling the number of vocal fold conditions producing irregular vibration.
Progressive fuzzy cation-π assembly of biological catecholamines
Authors: Hong Seonki , Wang Younseon , Park Sung Young , Lee Haeshin
Published: September 2018

Dopamine-melanin, polydopamine molecular assembly by cation-π bonds.
Self-folding of supramolecular polymers into bioinspired topology
Authors: Prabhu Deepak D. , Aratsu Keisuke , Kitamoto Yuichi , Ouchi Hayato , Ohba Tomonori , Hollamby Martin J. , Shimizu Nobutaka , Takagi Hideaki , Haruki Rie , Adachi Shin-ichi , Yagai Shiki
Published: September 2018

Supramolecular polymers undergo self-folding on a time scale of days into topologies resembling the protein’s tertiary structures.
Pulling apart photoexcited electrons by photoinducing an in-plane surface electric field
Authors: Wong E Laine , Winchester Andrew J. , Pareek Vivek , Madéo Julien , Man Michael K. L. , Dani Keshav M.
Published: September 2018

We make a movie, on the nanometer and femtosecond scale, as we pull apart electrons with a photoinduced surface field.
Colitis interruptus: LAGing gut inflammation
Authors: Mehta Pooja , Rosenblum Michael D.
Published: September 2018

Regulatory T cells indirectly suppress ILC3-driven colitis by suppressing gut-resident macrophages in a LAG-3–dependent manner.
Evaluation of a European-wide survey on paediatric endoscopy training
Authors: Broekaert Ilse Julia , Jahnel Joerg , Moes Nicolette , van der Doef Hubert , Ernst Angela , Amil Dias Jorge , Thomson Mike , Tzivinikos Christos
Published: September 2018

Objective

To evaluate quality of paediatric endoscopy training of Young members of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN).

Methods

An online questionnaire designed by the Young ESPGHAN Committee was sent to 125 Young ESPGHAN members between February 2014 and September 2015. The questionnaire comprised 32 questions addressing some general information of the participants and the structure of their paediatric gastroenterology, hepatology and nutrition programmes; procedural volume and terminal ileal intubation (TII) rate; supervision, assessments, participation in endoscopy courses and simulator training; and satisfaction with endoscopy training and self-perceived competency.

Results

Of 68 participants, 48 (71%) were enrolled in an official training programme. All alumni (n=31) were trained in endoscopy. They completed a median of 200 oesophagogastroduodenoscopies (OGDs) and 75 ileocolonoscopies (ICs) with a TII rate of >90% in 43%. There is a significant difference in numbers of ICs between the TII rate groups >90%, 50%–90% and <50% (median 150 vs 38 vs 55) (p<0.001). 11 alumni (35%) followed the ESPGHAN Syllabus during training. 25 alumni (81%) attended basic skills endoscopy courses and 19 (61%) experienced simulator training. 71% of the alumni were ‘(very) satisfied’ with their diagnostic OGD, while 52% were ‘(very) satisfied’ with their IC training. The alumni felt safe to independently perform OGDs in 84% and ICs in 71% after their training.

Conclusions

Despite reaching the suggested procedural endoscopy volumes, a rather low TII rate of >90% calls for end-of-training certifications based on the achievement of milestones of competency.
Working life expectancy in good and poor self-perceived health among Dutch workers aged 55–65 years with a chronic disease over the period 1992–2016
Authors: de Wind Astrid , van der Noordt Maaike , Deeg Dorly J H , Boot Cecile R L
Published: September 2018

Objectives

Several governments have taken measures to encourage prolonged working. It is therefore likely that older adults with a chronic disease are required to work longer in poor self-perceived health (SPH) than before. This study examines to what extent working life expectancy (WLE) in good and poor SPH changed between 1992 and 2016 in workers with a chronic disease from age 55 years onwards.

Methods

Three cohorts (1992, 2002 and 2012) of workers with a chronic disease aged 55–65 years were selected from the Longitudinal Aging Study Amsterdam with a 3-year follow-up each (n=705). A three-state survival model was estimated, modelling transitions between states ‘working with good SPH’, ‘working with poor SPH’ and ‘exit from work’. WLEs were estimated using Multistate Modelling and Estimating Life Expectancies using Continuous Time in R.

Results

Of the workers with a chronic disease, total WLEs at age 55 years were 5.2, 5.7 and 6.8 years in cohorts 1992, 2002 and 2012, respectively. Workers initially having poor SPH, had total WLE of 4.7 years of which 2.4 years in poor SPH in cohort 1992. These workers had total WLE of 5.2 years of which 3.3 years in poor SPH in cohort 2002, and total WLE of 6.5 years of which 3.6 years in poor SPH in cohort 2012.

Conclusions

Workers with a chronic disease extended their working lives by approximately 18 months from 1992 to 2016. In the first decade, unhealthy WLE increased, whereas in the second decade, healthy WLE increased, among both workers in general and workers initially having poor SPH.
“I Want to Be Like You!”: The Influence of Role Models on Entrepreneurial Intention
Authors: Fellnhofer Katharina , Mueller Susan
Published: September 2018

Explaining individual’s entrepreneurial intention is a central element in entrepreneurship research. The purpose of this paper is to illustrate that role models have an indirect effect on students’ entrepreneurial intention. We draw on a sample of 266 individuals and apply structural equation modeling. Our results show that role models have a positive and significant influence on entrepreneurial intention via the antecedents described in the theory of planned behavior, the entrepreneurial event model, and the integrated version of these models. With our study, we aim to contribute to a more comprehensive understanding of the path through which role models influence entrepreneurial intention.
Connecting the Links Between Leadership Styles and Virtual Team Effectiveness
Authors: Gross Raushan
Published: September 2018

This research attempted to connect the links between leadership styles and virtual team effectiveness. Linking leadership styles with virtual team effectiveness can result in virtual esprit de corps, which has been ignored in the literature. A theoretical model is provided and presents these links based on leadership style characteristics. Each style characteristic is matched with an effectiveness dimension, which was culled from supporting studies in the virtual domain. What this research provides, that others did not, is a topical view of leadership in a virtual context. The conceptualization and development of these links contribute to researchers, team leaders and managers, organizational theory, small business strategy, and policy makers involved in virtual configurations.
ROLE OF CALCINATION TEMPERATURES ON THE STRUCTURAL AND OPTICAL PROPERTIES OF NiO NANOPARTICLES
Authors: MOHAIDEEN H. MOHAMED , FAREED S. SHEIK , NATARAJAN B.
Published: September 2018

Nickel oxide nanoparticles (NiO NPs) were synthesized through template free sol–gel method. Synthesized particles were calcined at 300∘C, 500∘C and 700∘C for 2[Formula: see text]h and further the particles were characterized for its thermal, functional, structural, morphological and optical properties. The peak broadening analysis was undertaken in order to calculate the variation in size and strain components of the particles with the calcinations temperature. The Debye–Scherer, Williamson–Hall and Size-strain plot methods were employed in peak broadening analysis and were compared with TEM results. All the NiO NPs crystallite size and lattice strain value were found to be in good agreement with all the models. The TEM analysis revealed that the calcinations at 700∘C NiO NPs have sphere like structure of less than 20[Formula: see text]nm particles size value. The strong peak observed at 360.5[Formula: see text]nm bandgap emission relates to the bandgap of 3.44[Formula: see text]eV which is because of the near band edge emission.
OUT-OF-SAMPLE STOCK RETURN PREDICTION USING HIGHER-ORDER MOMENTS
Authors: FAIAS JOSÉ AFONSO , CASTEL-BRANCO TIAGO
Published: September 2018

We analyze variance, skewness and kurtosis risk premia and their option-implied and realized components as predictors of excess market returns and of the cross-section of stock returns. We find that the variance risk premium is the only moment-based variable to predict S&P 500 index excess returns, with a monthly out-of-sample [Formula: see text] above 6% for the period between 2001 and 2014. Nonetheless, all aggregate moment-based variables are effective in predicting the cross-section of stock returns. Self-financed portfolios long on the stocks least exposed to the aggregate moment-based variable and short on the stocks most exposed to it achieve positive and significant Carhart 4-factor alphas and a considerably higher Sharpe ratio than the S&P 500 index, with positive skewness.
Mitigation of Wind-Induced Vibration of a 600m High Skyscraper
Authors: Zhang J. W. , Li Q. S.
Published: September 2018

The serviceability of super-tall buildings depends primarily on the wind-induced structural responses, especially accelerations. To mitigate the discomforting structural vibrations, pendulum-type tuned mass damper (TMD) systems are commonly employed in high-rise buildings. However, for a super-tall building with a considerably low fundamental natural frequency, the suspension length of a pendulum-suspended TMD (PTMD) becomes too long to be feasible as it would occupy substantial building space. For the sake of saving valuable space in a super-tall building, a multistage PTMD system is recommended for vibration control. This paper presents a detailed assessment study on the performance of a multistage PTMD system designed for a 600 m high skyscraper located in a typhoon-prone region in China. Wind tunnel tests are first conducted to determine the wind loads on the building for estimation of structural dynamic responses for the scenarios with and without installation of the multistage PTMD system. Optimal design of the multistage PTMD system is then carried out through examining the mitigation efficiency of the PTMD system for a variety of mass and damping ratios. To restrict the strokes of mass dampers in the PTMD system, two-section damping strategy is proposed. The assessment results demonstrate that the multistage PTMD system with two-section damping can function efficiently to suppress the excessive vibrations of the skyscraper, while occupying a minimal space in vertical and horizontal directions. This paper aims to provide an effective and economic design strategy for vibration control of super-tall buildings under wind excitations.
Controlling the Power-Law Fluid Flow and Heat Transfer Under the External Magnetic Field Using the Flow Index and the Hartmann Number
Authors: Evcin Cansu , Uğur Ömür , Tezer-Sezgi̇n Münevver
Published: September 2018

The direct and optimal control solution of laminar fully developed, steady Magnetohydrodynamics (MHD) flow of an incompressible, electrically conducting power-law non-Newtonian fluid in a square duct is considered with the heat transfer. The fluid is subjected to an external uniform magnetic field as well as a constant pressure gradient. The apparent fluid viscosity is both a function of the unknown velocity and the flow index which makes the momentum equation nonlinear. Viscous and Joule dissipation terms are also included. The direct problem is solved by using Galerkin finite element method (FEM) with mixed finite elements and the control problem approach is the discretize-then-optimize procedure. The control formulations with the flow index parameter and the Hartmann number are given to regain the desired velocity profile and temperature isolines of the MHD flow.
Stochastic Response Analysis of a Built-Up Vibro-Acoustic System with Parameter Uncertainties
Authors: Zhang Zhenguo , Tian Jiajin , Huang Xiuchang , Hua Hongxing
Published: September 2018

In this paper, the quantification of uncertainty effects on stochastic responses of interior vibro-acoustic interaction systems with moderate geometry complexities and uncertain design parameters is investigated. A variational-based stochastic model is developed to predict the vibro-acoustic responses submitted to probabilistic parameters, and it is illustrated by application to a built-up system consisting of an irregular acoustic cavity backed up a plate assembly. The model is derived from the combination of the multi-domain Rayleigh–Ritz approach, used to solve the deterministic structural–acoustic equations, together with the generalized polynomial chaos expansion (gPCE) to represent propagation of uncertainty and estimate the statistical characteristics of the responses. Benchmark comparisons are made with the Monte Carlo simulations (MCS) to demonstrate the tremendous computational advantage of the present methodology. Uncertainty analysis is performed to ascertain the influence of random parameters on responses. The results reveal that system uncertainty is significant enough to affect the vibro-acoustic behaviors and hence the consideration of input uncertainties is necessary in analyses and designs to ensure the sustainable system performance.
New Insight Into Viscoelastic Finite Element Modeling of Time-Dependent Material Creep Problems Using Spherical Hankel Element Framework
Authors: Bahrampour M. , Hamzeh Javaran S. , Shojaee S.
Published: September 2018

In this study, a new formulation of finite element method (FEM) has been extracted to analyze 2D viscoelastic problems. As there has not been enough accuracy and not sufficient literature in classical finite element modeling of viscoelastic problems, using a new set of shape functions founded on radial basis functions (RBFs) is recommended. Applying these new, RBF-based shape functions instead of the classical Lagrangian ones, results in subtler answers and conducts a reconsideration over the usual numerical method. Hankel functions are chosen, enriched and summed up with polynomial terms. Therefore, they satisfy not only polynomial terms, but also the first- and second-order Bessel functions simultaneously; which, in the case of classic shape functions, happens only for the polynomial function field. This method illustrates an approach with faster convergence rate and better robustness in different manners. Hence, it is less time-consuming and economical. Finally, various numerical examples are provided for the comparison of analytical solution, classic FEM and Hankel-based FEM, which show the much better agreement of the proposed method with analytical solution in comparison to classic FEM. Also, the number of nodes and degrees of freedom are reduced noticeably while maintaining accuracy in the interpolation of the adopted procedure.
Thermo-Mechanical Vibration Analysis of Size-Dependent Functionally Graded Micro-Beams with General Boundary Conditions
Authors: Su Zhu , Jin Guoyong , Wang Lifeng , Wang Dan
Published: September 2018

A unified formulation for thermo-mechanical vibration analysis of size-dependent Timoshenko micro-beams comprised of functionally graded materials (FGMs) with general restraints is presented. The size effect is considered by incorporating the modified strain gradient theory into Timoshenko beam theory. The thermal and mechanical properties of FGMs are related to temperature and are assumed as continuous variation along the thickness. The Mori–Tanaka estimate is used for calculation of the material properties of FGM micro-beam. The formulation is deduced on the basis of the variational principle combined with penalty function method. The displacements and rotation of the FGM micro-beam are uniformly expanded by a modified Fourier series composed of traditional cosine series and some appropriate supplementary functions. Several comparisons of the present solutions with those from existing literature confirm the validity of the current formulation. In addition, a parametric study is given to demonstrate the influence of length scale parameters, gradient indices, end restraints and temperature changes on vibration characteristic of functionally graded micro-beam.
Wave Analysis of Planar Deployable Structures with Revolute Clearance Joints Based on Spectral Element Method
Authors: Ma Xiao-Fei , Li Tuan-Jie
Published: September 2018

Clearance is inevitable in the deployable mechanisms due primarily to the kinematic function requirements. This phenomenon affects the dynamic performances of deployed structures negatively. In this paper, the wave analysis of dynamic characteristics of planar structures with revolute clearance joints is developed by spectral element method. First, the spectral element model of revolute clearance joints is established. The radial and tangential springs and damping coefficients of revolute clearance joints are evaluated based on the contact model of elastic foundation. Then, the wave equations of two beams connected by a revolute clearance joint are derived, and extended to the case of multiple beams connected by revolute clearance joints. Finally, the dynamic response is analyzed for planar structures with single revolute clearance joint and multiple revolute clearance joints under the impact load. The wave propagation rules in planar structures with revolute clearance joints are revealed.