bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat transfer and pressure drop of Al2O3/water nanofluid in a tube equipped with double twisted tape inserts with different pitch ratios
Authors: Aghaie Abolfazl , Rabienataj Darzi A. Ali
Published: October 2018

In this paper, the effects of dual twisted tape inserts with different pitches on turbulent heat transfer and pressure drop are numerically investigated. A nanofluid is flowed inside a circular tube, which is under a constant heat flux condition. The Reynolds number varies from 5000 to 20 000 at a fixed Prandtl number of 7. Nine different cases are considered in the current study; three cases consist of a single twisted tape insert, three cases are related to twin twisted tapes with identical pitches, and the remaining cases consist of dual twisted tapes with different pitches for each insert. The predicted results indicate that inserting a dual twisted tape effectively increases the heat transfer 1.5 times more than that of the single insert with the penalty of high pressure drop. Also, the relative Nusselt number decreases with increase in Reynolds number for all the investigated cases. The heat transfer rates induced by dual inserts with different pitch ratios are higher than those with identical pitch ratios. Moreover, the maximum and minimum thermal performances belong to cases with Tr
1 = 2,
Tr
2 = 3 and
Tr
1 = 2,
Tr
2 = 2, respectively. And finally, it is stated here that adding nanoparticles improves the thermal performance of all cases in all the investigated Reynolds numbers.
Evaluation of a polyvinyl alcohol‐alginate based hydrogel for precise 3D bioprinting
Authors: Yu Fei , Han Xiao , Zhang Kaijia , Dai Bingyang , Shen Sheng , Gao Xiang , Teng Huajian , Wang Xingsong , Li Lan , Ju Huangxian , Wang Wei , Zhang Junfeng , Jiang Qing
Published: October 2018

In this study, we designed a polyvinyl alcohol (PVA)‐alginate based hydrogel and evaluated its cytocompatibility and printability. The samples were fabricated by 3D printing using a freeze–thaw process. The scanning electron microscope, material testing machine, rheometer, and cell counting kit‐8 assay were used to examine the morphology, mechanical properties, rheological properties, and cytocompatiblity of the scaffolds, respectively. The mechanical strength, cytocompatiblity, crosslinking time, and printability were remarkably improved with the use of PVA. To sum up, our data suggest that hybrid bio‐ink is more appropriate for precise 3D bioprinting due to its rapid prototyping capability and better cytocompatibility. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2944–2954, 2018.
The spectrum for large sets of ‐GDDs of type
Authors: Niu Xiaolei , Cao Haitao , Javadi Ramin
Published: October 2018

A ‐group divisible design (GDD) is called simple if no two blocks are identical. Two simple ‐GDDs and are called disjoint if . A set of more than two simple ‐GDDs is called disjoint if each pair of them is disjoint. The collection of disjoint ‐GDDs of type is called a large set. In this paper, we completely solve the existence of large sets of ‐group divisible designs (GDDs) of type and the existence of a simple ‐GDD of type .
Adamantinoma of bone: Long‐term follow‐up of 46 consecutive patients
Authors: Houdek Matthew T. , Sherman Courtney E. , Inwards Carrie Y. , Wenger Doris E. , Rose Peter S. , Sim Franklin H.
Published: October 2018

Background

Adamantinomas are rare bone tumors, commonly affecting the tibia. Due to the rare nature of disease, previous studies are small or from multiple centers. The purpose of this study is to investigate outcomes of patients with adamantinoma treated in a single institution.

Methods

Forty‐six histological confirmed adamantinomas of the extremities were reviewed at our institution between 1939 and 2012. Follow‐up data included clinical and radiographical information focusing on complications, local recurrence, metastasis, and overall survival after the treatment. The mean follow‐up was 16 years (range 2‐42 years).

Results

The most common location was the tibia (n = 31). Patients commonly presented with pain and swelling. The mean age was 24 years (7‐79 years). Thirty‐seven patients were treated with limb salvage. The 39% of patients required a reoperation. The 10‐year disease specific‐ and recurrence free survival was 92% and 72%, with three patients having a recurrence over 15 years postoperative. Older (> 20 years) patients and males were at increased risk of local recurrence (P < 0.05).

Conclusion

Treatment of adamantinoma of the long bone consists of limb‐salvage surgery. Male patients should be cautioned on their increased risk of disease recurrence, and advocate for continued surveillance of patients even greater than 15‐years postoperatively due to late tumor recurrence.
The prognostic significance of adrenocortical carcinomas identified incidentally
Authors: Rossfeld Kara K. , Maithel Shishir K. , Prescott Jason , Wang Tracy S. , Fields Ryan C. , Weber Sharon M. , Sicklick Jason K. , Yopp Adam C. , Duh Quan‐Yang , Solorzano Carmen C. , Votanopoulos Konstantinos I. , Hatzaras Ioannis , Poultsides George A. , Shirley Lawrence A. ,   and the U.S. Adrenocortical Carcinoma Study Group
Published: October 2018

Background and Objectives

Little is known regarding the difference in prognosis among patients who have an incidentally discovered adrenocortical carcinoma (ACC) vs those who present with signs or symptoms. We aimed to explore differences in the outcomes of these two populations.

Methods

Data were collected on patients who underwent resection of ACC at 1 of 13 institutions between January 1993 and December 2014. Presentations were categorized as incidental vs symptomatic and outcomes were compared.

Results

Among 227 patients, 100 were diagnosed incidentally while 127 patients presented with symptoms/signs. Clinical and pathological features were comparable among incidental vs nonincidental patients with ACC following the exceptions. Patients with incidentalomas were more likely to have a T1/T2 tumor (55.8% vs 34.8%;
P < 0.01) and less likely to have a functional tumor (33.7% vs 47.9%;
P = 0.04). Patients with an incidental ACC had improved median recurrence‐free survival (RFS; 29.4 months) compared with patients with a nonincidental ACC (13.0 months;
P = 0.03); however, on multivariable analysis, incidental ACC was not an independent predictor of survival.

Conclusions

Patients with resected ACC identified incidentally had an improved RFS compared with the patients who presented with symptoms or signs. This difference may be related to the patients with incidental tumors having earlier T‐stage disease.
High‐definition point‐of‐view intraoperative recording using a smartphone: A hands‐free approach
Authors: Hakimi Amir A. , Hu Allison C. , Pham Tiffany T. , Wong Brian J. F.
Published: October 2018

Objectives/Hypothesis

Intraoperative recording devices are being increasingly used to provide video for contemporary surgical training. The objective of this study was to evaluate the use of a smartphone as a low‐cost alternative to obtain high‐resolution video from the surgeon's perspective.

Study Design

A study evaluating the feasibility of using a head‐mounted smartphone with a telephoto lens for point‐of‐view surgical videography.

Methods

Video recordings of a rhinoplasty procedure were taken using a head‐mounted smartphone and two handheld cameras, a Canon Powershot SD1400 IS and a Sony HandyCam HDR‐CX160. Video clips were shown to 16 blinded otolaryngology residents (n = 10) and attending physicians (n = 6) for individual video evaluation using a Likert scale (1 being poor quality, 5 being excellent quality). In addition, the study participants were asked to select which video clip they preferred when presented to them side by side.

Results

The iPhone 7 was given the highest overall mean video quality rating of 3.9 ± 0.57 and was preferred over the two handheld cameras by nearly all surveyed surgeons. The Canon Powershot SD1400 IS was given a mean rating of 3.3 ± 1.0 and preferred over the SonyHandyCam HDR‐CX160 by all surgeons. The Sony HandyCam HDR‐CX160 was given a mean rating of 1.5 ± 0.13.

Conclusions

A head‐mounted smartphone equipped with a telephoto lens provides a novel method to intraoperative surgical recording. The design is simple, low cost, and allows the surgeon to capture fine anatomical detail from the desirable point‐of‐view perspective.

Level of Evidence

NA Laryngoscope, 129:578–581, 2019
Pentraxin 3 level is elevated in hereditary hemorrhagic telangiectasia and reflects the severity of disease‐associated epistaxis
Authors: Steineger Johan , Ueland Thor , Aukrust Pål , Michelsen Anikka , Osnes Terje , Heimdal Ketil , Dheyauldeen Sinan
Published: October 2018

Objectives/Hypothesis

We aimed to investigate if vascular endothelial growth factor (VEGF) and other angiogenic and inflammatory factors correlated with the clinical presentation in hereditary hemorrhagic telangiectasia (HHT) patients, particularly in regard to the severity of epistaxis.

Study Design

Prospective, comparative, single‐center study.

Methods

One hundred nine samples were collected from 75 HHT patients attending the ear, nose, and throat department at Oslo University Hospital from February 2012 to August 2013. For comparison, samples were collected from 16 healthy controls. Angiogenic and inflammatory factors related to endothelial cell activation were analyzed by enzyme immunoassays. The grade of epistaxis was evaluated using the Epistaxis Severity Score and epistaxis Intensity, Frequency, and Need for Blood Transfusion score at the day of blood sampling. The presence of internal organ manifestations in the HHT group was recorded.

Results

Pentraxin 3 (PTX3) was the only factor that was significantly higher in the HHT patients than the controls and showed significant correlation to the epistaxis severity grade and the hemoglobin level. The VEGF level was higher in the HHT patients compared to controls but not to a significant degree. In addition, a significant correlation of the level of VEGF and the grade of epistaxis could not be observed. Also, no significant correlations were observed between the presence of internal organ manifestations and the level of angiogenic factors.

Conclusions

PTX3, at least partly reflecting vascular inflammation, can be a potential biomarker for the severity of HHT associated epistaxis. The serum level of VEGF was not correlated with the severity of epistaxis in the HHT patients.

Level of Evidence

2 Laryngoscope, 129:E44–E49, 2019
Geometric classification of warped products isometrically immersed into Sasakian space forms
Authors: Akram Ali , Pişcoran Laurian‐Ioan
Published: October 2018

The main objective of this paper is to study the warped product pointwise semi‐slant submanifolds which are isometrically immersed into Sasakian manifolds. First, we prove some characterizations results in terms of the shape operator, under which influence a pointwise semi‐slant submanifold of a Sasakian manifold can be reduced to a warped product submanifold. Then, we determine a geometric inequality for the second fundamental form regarding to intrinsic invariant and extrinsic invariant using the Gauss equation instead of the Codazzi equation. Evenmore, we give some applications of this inequality into Sasakian space forms, and we will investigate the status of equalities in the inequality. As a particular case, we provide numerous applications of the Green lemma, the Laplacian of warped functions and some partial differential equations. Some triviality results for connected, compact warped product pointwise semi‐slant submanifolds of Sasakian space form by means of Hamiltonian and the kinetic energy of warped function involving boundary conditions are established.
The effects of power on consumers’ evaluation of a luxury brand's corporate social responsibility
Authors: Chang Dae Ryun , Jang Joonsuk , Lee Hosun , Nam Myungwoo
Published: October 2018

This paper examines how power affects consumers’ responses to corporate social responsibility (CSR) initiatives of luxury brands. The results of three studies show that high‐power individuals evaluated a luxury brand's CSR campaign more positively than low‐power individuals. High‐power individuals viewed CSR activities as being more fluent than low‐power individuals. This study further demonstrates that power influences consumers’ responses to nonluxury brand's CSR activities. Low‐power individuals, who are more receptive to warmth, evaluated nonluxury brand's CSR more favorably rather than high‐power individuals.
Ligninolytic enzymes: Versatile biocatalysts for the elimination of endocrine‐disrupting chemicals in wastewater
Authors: Falade Ayodeji O. , Mabinya Leonard V. , Okoh Anthony I. , Nwodo Uchechukwu U.
Published: October 2018

Direct municipal wastewater effluent discharge from treatment plants has been identified as the major source of endocrine‐disrupting chemicals (EDC) in freshwaters. Consequently, efficient elimination of EDC in wastewater is significant to good water quality. However, conventional wastewater treatment approaches have been deficient in the complete removal of these contaminants. Hence, the exploration of new and more efficient methods for elimination of EDC in wastewater is imperative. Enzymatic treatment approach has been suggested as a suitable option. Nonetheless, ligninolytic enzymes seem to be the most promising group of enzymes for EDC elimination, perhaps, owing to their unique catalytic properties and characteristic high redox potentials for oxidation of a wide spectrum of organic compounds. Therefore, this paper discusses the potential of some ligninolytic enzymes (laccase, manganese peroxidase, and versatile peroxidase) in the elimination of EDC in wastewater and proposes a new scheme of wastewater treatment process for EDC removal.
Molecular characterization of PRKN structural variations identified through whole‐genome sequencing
Authors: Bravo Paloma , Darvish Hossein , Tafakhori Abbas , Azcona Luis J. , Johari Amir Hossein , Jamali Faezeh , Paisán‐Ruiz Coro
Published: October 2018

Background

Early‐onset Parkinson's disease (PD) is the most common inherited form of parkinsonism, with the PRKN gene being the most frequently identified mutated. Exon rearrangements, identified in about 43.2% of the reported PD patients and with higher frequency in specific ethnicities, are the most prevalent PRKN mutations reported to date in PD patients.

Methods

In this study, three consanguineous families with early‐onset PD were subjected to whole‐genome sequencing (WGS) analyses that were followed by Sanger sequencing and droplet digital PCR to validate and confirm the disease segregation of the identified genomic variations and to determine their parental origin.

Results

Five different PRKN structural variations (SVs) were identified. Because the genomic sequences surrounding the break points of the identified SVs might hold important information about their genesis, these were also characterized for the presence of homology and repeated sequences.

Conclusion

We concluded that all identified PRKN SVs might originate through retrotransposition events.
Approximation properties of Szász‐Mirakyan‐Kantorovich type operators
Authors: Aral Ali , Limmam Mohamed Lemine , Ozsarac Firat
Published: October 2018

In this paper, we introduce and study new type Szász‐Mirakyan‐Kantorovich operators using a technique different from classical one. This allow to analyze the mentioned operators in terms of exponential test functions instead of the usual polynomial type functions. As a first result, we prove Korovkin type approximation theorems through exponential weighted convergence. The rate of convergence of the operators is obtained for exponential weights.
Convergence analysis for iterative learning control of conformable fractional differential equations
Authors: Wang Xiaowen , Wang JinRong , Shen Dong , Zhou Yong
Published: October 2018

This paper mainly deals with iterative learning control for the conformable fractional differential equations. The standard P‐type, Dα‐type, and conformable PIαDα‐type learning updating laws are proposed to derive the convergence results for nonlinear and linear problems varying with the initial state is (not) coincident with the desired initial state. Finally, numerical examples are given to illustrate the results.
On weighted Dirichlet spaces of monogenic functions in
Authors: Avetisyan Karen , Gürlebeck Klaus
Published: October 2018

In a recent paper of ours, we proved that a special “harmonic conjugation” operator is not bounded in weighted Bergman spaces
of quaternion‐valued functions in the 3D ball. In the present paper, we prove that, in contrast to the Bergman spaces case, the same operator is bounded in weighted Dirichlet spaces
of quaternion‐valued functions in the 3D ball. Furthermore, applying another approach for a construction of harmonic conjugates, we extend the result to weighted Dirichlet spaces
with 1 < p < ∞.
Commutativity of first‐order discrete‐time linear time‐varying systems
Authors: Koksal Mehmet Emir
Published: October 2018

After introducing the concept of commutativity for continuous‐time linear time‐varying systems, the related literature and the results obtained so far are presented. For a simple introduction of the commutativity of discrete‐time linear time‐varying systems, the problem is formulated for first‐order systems. Finally, explicit necessary and sufficient conditions for the commutativity of first‐order discrete‐time linear time‐varying systems are derived, and their advantageous use in digital system design is illustrated, which are the main objectives of the paper. The results are verified by examples which include an application in amplitude modulation for digital telecommunication.
Partial dimension reduction for the heat equation in a domain containing thin tubes
Authors: Amosov Andrey , Panasenko Grigory
Published: October 2018

The heat equation in considered in a domain containing thin cylindrical tubes with Neumann's boundary condition at the lateral boundary of these tubes. This problem is reduced to a hybrid dimension problem keeping the initial dimension out of thin tubes and reducing it to the one‐dimensional heat equation within the tubes at some distance from the bases of the cylinders. Junction of models of different dimensions is done according to the method of asymptotic partial decomposition of domain. The difference of solutions of the original and partially reduced problems is estimated. This result generalizes the method of partial dimension reduction for the case when the domain has only one restriction that it contains several thin cylinders possibly of different orders of diameters.
Infinitely many solutions for magnetic fractional problems with critical Sobolev‐Hardy nonlinearities
Authors: Yang Libo , An Tianqing
Published: October 2018

In this paper, we study the existence of infinitely many solutions of the following degenerate magnetic fractional problem involving critical Sobolev‐Hardy nonlinearities:

urn:x-wiley:mma:media:mma5317:mma5317-math-0001
where s ∈ (0,1), N > 2s,
is the fractional Hardy‐Sobolev critical exponent with α ∈ [0,2s), λ is a positive real parameter,
is a Kirchhoff function,
is a magnetic potential function, and
is the fractional magnetic operator. By using the new version of symmetric mountain pass theorem of Kajikiya, we prove that the problem admits infinitely many solutions for the suitable value of λ.
Analytic rogue wave solutions for a generalized fourth‐order Boussinesq equation in fluid mechanics
Authors: Ma Yu‐Lan , Li Bang‐Qing
Published: October 2018

A bilinear transformation method is proposed to find the rogue wave solutions for a generalized fourth‐order Boussinesq equation, which describes the wave motion in fluid mechanics. The one‐ and two‐order rogue wave solutions are explicitly constructed via choosing polynomial functions in the bilinear form of the equation. The existence conditions for these solutions are also derived. Furthermore, the system parameter controls on the rogue waves are discussed. The three parameters involved in the equation can strongly impact the wave shapes, amplitudes, and distances between the wave peaks. The results can be used to deeply understand the nonlinear dynamical behaviors of the rogue waves in fluid mechanics.
Ten‐element MIMO antenna for 5G terminals
Authors: Deng Jing‐Ya , Yao Jiao , Sun Dong‐Quan , Guo Li‐Xin
Published: October 2018

A MIMO antenna with 10 elements operating on 3.3‐3.6 GHz for 5G applications is proposed. The 10 elements of the proposed MIMO antenna include six monopoles and four slots with coupled feed. The monopoles and slots are alternately placed along the four sides of the mobile terminal with different radiating modes. The antenna is printed on a planar substrate, resulting in low cost and easy fabrication. The antenna is simulated, fabricated, and measured, the isolations are better than 11 dB, the efficiencies are about 50‐76%. The envelop correlation coefficient (ECC) is lower than 0.15 between any two antenna elements, and the calculated channel capacity is reached about 48‐51 bps/Hz, which is 7 bps/Hz lower than the ideal 10 × 10 MIMO channel.
A 2‐element meandered‐line slot‐based frequency reconfigurable MIMO antenna system
Authors: Raza A. , Khan Muhammad U. , Tahir Farooq A. , Hussain R. , Sharawi Mohammad S.
Published: October 2018

A dual‐band frequency reconfigurable multiple‐input multiple‐output (MIMO) antenna system is presented. The design consists of two slot‐based antenna elements made on an FR4 board and occupies an area of 50 × 100 mm2. The antenna operates in two bands. Further, a varactor diode is integrated across the slot to achieve the frequency reconfiguration. The antenna can be reconfigured to operate in both bands from 1.35‐1.62 GHz and 1.95‐2.2 GHz with minimum −6 dB bandwidth of 50 MHz. A defected ground structure (DGS) between the antenna elements is used to improve the isolation. With compact size and low envelope correlation coefficient (ECC), the design is suitable for long‐term evolution (LTE) systems and cognitive radio (CR) enabled platforms.
A compact dual‐band rectenna for ambient RF energy harvesting
Authors: Adam Ismahayati , M. Yasin M. Najib , A. Rahim Hasliza. , Soh P. J. , Abdulmalek M. Fareq
Published: October 2018

A compact broadband ambient RF energy harvester operating from 1800 MHz up to 2.5 GHz is proposed in this paper. This work is motivated by the huge amount of free and continuously available RF energy in the surroundings that can be utilized into useable energy. Harvest performance is investigated using two antennas in this work, a circular polarized and an array antenna. Due to low ambient power densities, a multistage rectifier is utilized to improve the output dc voltage of the proposed system. Measurements indicate the system is capable of harvesting up to 1.8 Vdc output from nondedicated ambient RF energy sources in an urban area, which is significant in the absence of other energy sources.
Interest of chromosomal microarray analysis in the prenatal diagnosis of fetal intrauterine growth restriction
Authors: Brun Stephanie , Pennamen Perrine , Mattuizzi Aurelien , Coatleven Frederic , Vuillaume Marie Laure , Lacombe Didier , Arveiler Benoit , Toutain Jerome , Rooryck Caroline
Published: October 2018

Objective

The aim of this study is to evaluate the diagnostic utility of prenatal diagnosis using the chromosomal microarray analysis (CMA) for fetuses presenting with isolated or associated intrauterine growth restriction (IUGR).

Method

We retrospectively included all fetuses with IUGR referred for prenatal testing and studied by rapid fluorescence in situ hybridization (FISH), karyotype, and CMA.

Results

Among the 162 IUGR fetuses (78 associated and 84 isolated IUGR) included, 15 had an abnormal FISH result: 10 associated and five isolated fetal IUGRs. Among the 143 fetuses studied by CMA, 10 (7%) presented pathogenic copy number variations (CNVs). All 10 were in the associated fetal IUGR group (10/65 or 15.4%; 95% confidence interval [CI]: 8.4%‐26.2%) versus 0/78 in the isolated fetal IUGR group (95% CI: 0%‐5.6%). Six fetuses (4.2%) carried variants of unknown significance (VOUS) (three associated and three isolated fetal IUGRs).

Conclusion

Our study highlights the added value of CMA in the case of associated fetal IUGR with an incremental yield of 6.1% (4/65) over karyotyping. No pathogenic CNVs were reported in the isolated fetal IUGR group. More studies must be conducted to determine when and whether CMA would be wisely indicated in this population.
Atomic Layer Deposited Oxygen‐Deficient TaOx Layers for Electroforming‐Free and Reliable Resistance Switching Memory
Authors: Kuzmichev Dmitry S. , Lebedinskii Yuri Y. , Hwang Cheol Seong , Markeev Andrey M.
Published: October 2018

Oxygen‐deficient TaOx layers are grown by a radical‐enhanced atomic layer deposition (REALD) process on a chemically active bottom electrode (Ta) to create electroforming‐free resistance switching random access memory (ReRAM) cells. When the top electrode is Pt, the Ta/TaOx/Pt device shows a completely electroforming‐free behavior with a pulse‐switching induced endurance cycle of up to 6 × 106 cycles. This is due to the abundantly present oxygen vacancies within the TaOx layer, which eliminate the need to create further oxygen vacancies during the electroforming cycles in other types of oxide‐based ReRAM cells. The adoption of the Pt top electrode contributes to the suppression of the leakage current, making the switching reliable. When the top electrode is changed to the more production‐compatible Ru, which is also grown by another REALD, the devices show very mild electroforming behavior with an increased leakage current. Due to these slight decreases in the electrical performance, the switching endurance can be confirmed only up to 6 × 104 cycles with the help of an incremental step pulse programming technique.
Multi‐manipulators coordination for bilateral teleoperation system using fixed‐time control approach
Authors: Yang Y. , Hua C. , Guan X.
Published: October 2018

In this paper, the fixed‐time synchronization control problem for bilateral teleoperation system composed of a single master manipulator and multiple cooperative slave manipulators with system uncertainties and external disturbances is addressed. The multiple cooperative slave manipulators have the capability to perform some complex tasks that are difficult or even impossible to be executed by a single slave manipulator. In order to control the multiple slave manipulators handling a common object with faster speed and higher accuracy, a new adaptive neural networks (NNs)–based fixed‐time control scheme is proposed. First, under the assumptions that the slave manipulators are rigidly grasping a nondeformable object, an integrated dynamic model composed of multiple slave manipulators and an object is derived. The object's grasping forces are concealed in the derived dynamics and can be controlled independent of the motion space. Then, a new nonsingular integral terminal sliding mode providing fixed‐time convergence of the velocity and position errors is designed with high‐degree terms and lower‐degree terms. By setting proper initial value of the integral function, the system settling time will be reduced greatly. Moreover, the corresponding adaptive NN‐based fixed‐time control approach is proposed by employing the strong approximation of the NNs. It is proved that the closed‐loop teleoperation system is semiglobally fixed‐time stable and the synchronization errors between the local manipulator and the object will converge to zero in fixed time for any initial condition of the master and the slaves. Finally, simulation and experiment are both performed to verify the effectiveness of the proposed method.
Boundary control of linear stochastic reaction‐diffusion systems
Authors: Wu Kai‐Ning , Liu Xiao‐Zhen , Shi Peng , Lim Cheng‐Chew
Published: October 2018

This paper considers the boundary control problem for linear stochastic reaction‐diffusion systems with Neumann boundary conditions. First, when the full‐domain system states are accessible, a boundary control is designed, and a sufficient condition is established to ensure the mean‐square exponential stability of the resulting closed‐loop system. Next, when the full‐domain system states are not available, an observer‐based control is proposed such that the underlying closed‐loop system is stable. Furthermore, observer‐based controller is designed for the systems with anH∞performance. Simulation examples are given to demonstrate the effectiveness and potential of the new design techniques.
The Nature and Measurement of Children's Early Composing
Authors: Quinn Margaret F. , Bingham Gary E.
Published: October 2018

Young children's writing development (i.e., writing occurring in preschool and kindergarten prior to the skilled, fluent writing associated with formal schooling) is an important predictor of later literacy achievement. Current policy movements, such as the Common Core State Standards, invoke increased composing demands, yet research has often focused on children's growing ability to transcribe (e.g., form letters, spell words) rather than their ability to compose text and generate ideas. The current study examined literature from the past 30 years to determine the prevailing operational definitions of early composing and the ways in which composing has been measured to date. Given inclusion criteria, the authors collected and coded articles to determine trends and prevailing approaches (n = 445). Findings revealed that various theoretical and conceptual frames influenced approaches to assessing children's composing, yielding little shared understanding of the nature and development of early composing. Findings also revealed that tasks used to measure children's early composing development have not always aligned with theoretical notions of early writing, nor have they been properly operationalized in psychometrically sound, valid, and reliable ways. Further, analyses of trends across time yielded insight into the evolving conceptualizations and prioritization of particular aspects of early composing, such as the focus on children's use of conventional encoding in a composing task context. Implications for practice are discussed in light of these findings.
Mindfulness‐based program for stress reduction in infertile women: Randomized controlled trial
Authors: Nery Simone F. , Paiva Sara P.C. , Vieira Érica L. , Barbosa Andressa B. , Sant'Anna Edna M. , Casalechi Maira , Dela Cruz Cynthia , Teixeira Antônio L. , Reis Fernando M.
Published: October 2018

Infertile women often experience chronic stress, which may have a negative impact on general well‐being and may increase the burden of infertility. In this open‐label, parallel, randomized controlled trial, infertile women aged 18–50 years (median 37 years) were assigned to an 8‐week mindfulness‐based program (MBP) or no intervention. The primary outcome was stress severity measured by the Lipp's Stress Symptoms Inventory (ISSL). Data were analyzed by modified intent‐to‐treat principle, which included all cases available to follow‐up regardless of adherence to the intervention (62 participants from the MBP group and 37 from the control group). The median number of symptoms of chronic stress recorded in the past month decreased from six (interquartile range 2 to 9) before the MBP to two (interquartile range 1 to 4) after the intervention (p < 0.001, repeated measures analysis of variance with Time × Group interaction). Depressive symptoms also decreased after MBP, whereas general well‐being improved (p < 0.01 for both outcomes). Hair cortisol and serum brain‐derived neurotrophic factor (BDNF) did not change significantly between preintervention and postintervention. None of the outcomes changed significantly in the control group. MBP was effective in reducing stress and depressive symptoms while increasing general well‐being in infertile women.
Superconformal index of higher derivative $$ \mathcal{N}=1 $$ multiplets in four dimensions
Authors: Beccaria Matteo , Tseytlin Arkady A.
Published: October 2018

Abstract

Supersymmetric partition function of$$ \mathcal{N}=1 $$N=1superconformal theories onSβ1 × S3is related to the superconformal index receiving contributions from short representations. The leading coefficients in the smallβ(high “temperature”) expansion of the index were previously related to the conformal anomaly coefficients of the theory. Assumptions underlying universality of these relations were tested only for simplest low-spin unitary multiplets. Here we consider examples of higher derivative non-unitary$$ \mathcal{N}=1 $$N=1multiplets that naturally appear in the context of extended conformal supergravities and compute their superconformal index. We compare the coefficients in the smallβexpansion of the index with those proposed earlier for unitary multiplets and suggest some modifications that should apply universally to all types of theories. We also comment on the structure of subleading terms and the case of$$ \mathcal{N}=4 $$N=4conformal supergravity.
Pentagon functions for massless planar scattering amplitudes
Authors: Gehrmann T. , Henn J. M. , Lo Presti N. A.
Published: October 2018

Abstract

Loop amplitudes for massless five particle scattering processes contain Feynman integrals depending on the external momentum invariants: pentagon functions. We perform a detailed study of the analyticity properties and cut structure of these functions up to two loops in the planar case, where we classify and identify the minimal set of basis functions. They are computed from the canonical form of their differential equations and expressed in terms of generalized polylogarithms, or alternatively as one-dimensional integrals. We present analytical expressions and numerical evaluation routines for these pentagon functions, in all kinematical configurations relevant to five-particle scattering processes.
Walking, weak first-order transitions, and complex CFTs
Authors: Gorbenko Victor , Rychkov Slava , Zan Bernardo
Published: October 2018

Abstract

We discuss walking behavior in gauge theories and weak first-order phase transitions in statistical physics. Despite appearing in very different systems (QCD below the conformal window, the Potts model, deconfined criticality) these two phenomena both imply approximate scale invariance in a range of energies and have the same RG interpretation: a flow passing between pairs of fixed point at complex coupling. We discuss what distinguishes a real theory from a complex theory and call these fixed points complex CFTs. By using conformal perturbation theory we show how observables of the walking theory are computable by perturbing the complex CFTs. This paper discusses the general mechanism while a companion paper [1] will treat a specific and computable example: the two-dimensionalQ-state Potts model withQ> 4. Concerning walking in 4d gauge theories, we also comment on the (un)likelihood of the light pseudo-dilaton, and on non-minimal scenarios of the conformal window termination.
From Privilege to Prevalence: Contextual Effects of Women’s Schooling on African Marital Timing
Authors: Frye Margaret , Lopus Sara
Published: October 2018

In Africa and elsewhere, educated women tend to marry later than their less-educated peers. Beyond being an attribute of individual women, education is also an aggregate phenomenon: the social meaning of a woman’s educational attainment depends on the educational attainments of her age-mates. Using data from 30 countries and 246 birth cohorts across sub-Saharan Africa, we investigate the impact of educational context (the percentage of women in a country cohort who ever attended school) on the relationship between a woman’s educational attainment and her marital timing. In contexts where access to education is prevalent, the marital timing of uneducated and highly educated women is more similar than in contexts where attending school is limited to a privileged minority. This across-country convergence is driven by uneducated women marrying later in high-education contexts, especially through lower rates of very early marriages. However, within countries over time, the marital ages of women from different educational groups tend to diverge as educational access expands. This within-country divergence is most often driven by later marriage among highly educated women, although divergence in some countries is driven by earlier marriage among women who never attended school.
Optimization experiment on eccentric lapping of cylindrical rollers
Authors: Su Jia , Yuan Julong , Zhang Sen , Lv Binghai
Published: October 2018

Cylindrical rollers are important elements of bearings, and their machining accuracy and consistency affect the bearing quality. Using a GCr15 cylindrical roller of Φ11 × 12 as the processing object in this study, the effects of loading pressure, abrasive concentration, and speed combination on cylindrical roller machining precision were investigated using the orthogonal experimental design method on a double-side eccentric pendulum lapping and polishing machine. The machining parameters of the lapping stage were optimized, and the lapping optimal process parameters were determined by S/N response analysis and analysis of variance (ANOVA). The results show that when the experiment was optimized using loading pressure of 10 N/roller, abrasive concentration (3000#Al2O3) of 20.0 wt%, and rotational speed combination, the material removal rate (MRR) of cylindrical roller reached 0.0896 μm/min; the average roughness of the batch decreased from 0.056 μm to 0.027 μm, 51.8% lower than the original batch average roughness, and the deviation decreased from the initial 0.022 μm to 0.014 μm; the batch average roundness error decreased from 0.47 μm to 0.28 μm, 40.4% lower than the original batch average roundness error, and the deviation decreased from the initial 0.19 μm to 0.038 μm; and the batch average diameter variation decreased from 4.5 μm to about 3.6 μm, 20% lower than the original batch average diameter variation. The double-side eccentric lapping of cylinder rollers does not only lead to improvement in the surface quality and shape accuracy of rollers, but also improvement in the batch consistency.
Anisotropic brittle-ductile transition of monocrystalline sapphire during orthogonal cutting and nanoindentation experiments
Authors: Maas Philipp , Mizumoto Yuta , Kakinuma Yasuhiro , Min Sangkee
Published: October 2018

Single-crystal sapphire is utilized as a high-performance engineering material, especially in extreme and harsh environments. However, due to its extreme hardness and brittleness, the machinability of sapphire is still a challenge. By means of nanoindentation and plunge-cut experiments, the anisotropic brittle-ductile transition of the prismatic M-plane and rhombohedral R-plane is examined by analyzing crack morphologies and the critical depth-of-cut (CDC). The experimental results of the nanoindentation tests are correlated to the plunge-cut experiment. Both the prism plane and the rhombohedral crystal plane exhibit a two-fold symmetry of ductility with various crack patterns along the machined grooves. The direction-dependent plasticity of the hexagonal sapphire crystal is mainly connected to a twinning process accompanied by slip dislocation.
Noble-metal mineralization of the Adycha–Taryn metallogenic zone: geochemistry of stable isotopes, fluid regime, and ore formation conditions
Authors: Gamyanin G.N. , Fridovsky V.Yu. , Vikent’eva O.V.
Published: October 2018

The regional geologic setting of the Adycha–Taryn metallogenic zone, one of the areas most productive for noble-metal mineralization in northeastern Russia, is discussed. The intricate metallogenic history of the zone and the prolonged geodynamic activity of its ore-hosting structures are documented. Different types of mineralization, such as hydrothermal-metamorphogenic, gold–bismuth, gold–quartz, gold–antimony, and silver–antimony, are described. New data on the isotopic compositions of oxygen in quartz, sulfur in sulfides, and oxygen and carbon in carbonates from different mineralization types are presented. The early metamorphogenic quartz beyond the ore zones has δ18O = + 20.1 ± 2.0‰. At the gold–bismuth deposits, the δ18O values of quartz are within the narrow range of + 12.5 ± 0.4‰. Quartz from the gold–quartz mineralization shows much wider variation in δ18O values, from + 14.2 to + 19.5‰. A similar range (δ18O = + 16.1 to + 19.2‰) is observed for the gold–antimony mineralization. Cryptograined quartz from the silver–antimony mineralization is enriched in light oxygen isotopes (δ18O = –3.2 to + 4.7‰). The following δ34S values (‰) have been established in sulfides of mineralization of different types: gold–bismuth –3.7 to –2.2 (Apy) and –6.7 to –6.8 (Py); gold–quartz –2.1 to + 2.4 (Apy), –6.6 to + 5.4 (Py), and –6.1 to + 4.2 (St); gold–antimony –2.0 to + 1.6 (Apy), –3.5 to + 2.1 (Py), and –5.3 to + 0.2 (St); and silver–antimony –2.0 to –1.9 (Apy), –2.2 ± 0.1 (Py), and –5.7 to –5.6 (St). The δ13C and δ18O values are contrasting in the studied types of mineralization, varying respectively from –6.9 to –5.9‰ and from + 2.1 to + 5.7‰ (gold–bismuth), from –9.1 to –6.1‰ and from + 12.4 to 18.7‰ (gold–quartz), from –12.1 to –9.5‰ and from + 15.0 to + 16.3‰ (gold–antimony), from –11.6 to –11.1‰ and from + 1.5 to + 4.7‰ (silver–antimony). Metamorphogenic calcites are rich in both heavy C (–1.1 to –1.7‰) and heavy O (+ 20.3 to + 20.5‰) isotopes. Microthermometric study and crush–leach analysis of fluid inclusions have revealed differences in the composition of ore-forming fluids and formation conditions for different types of mineralization. The isotopic compositions of O, C, and S of mineral-forming fluids suggest a significant input of magmatic fluids to the formation of gold–bismuth and gold–antimony deposits, the contribution of metamorphic fluids increases at gold–quartz deposits, and meteoric water is involved in the formation of silver–antimony deposits.
The International Law of Property
Authors: Alvarez José E.
Published: October 2018

On the surface, the two books under review seem to have little in common. The Bonnitcha/Poulsen/Waibel (BPW) book, written by two legal academics and a political scientist, provides a balanced, fact-grounded account of international investment agreements (IIAs) and investor-state dispute settlement (ISDS). This is the “international treaty regime” in that book's title which the authors argue needs to be distinguished from the broader “international regime complex” that their book explicitly does not address, namely the number of other international instruments that at least incidentally also protect foreign investments (including, for example, political risk insurance, tax treaties, certain World Trade Organization agreements, and certain human rights treaties like the European Convention on Human Rights (ECHR)) (p. 7 and Figure 1.2). As one of the encomiums on its back cover page suggests, the BPW book seeks to answer the fraught competing contentions of defenders and critics of the regime that all too frequently generate “more heat than light.” Their book dispassionately synthesizes the available legal, economic, and political literature relevant to understanding the investment treaty regime's oft-proclaimed “legitimacy crisis.” It seeks to supply lawyers needing political context and political scientists needing legal knowledge with the unfiltered facts required to assess whether such a “crisis” exists and, if so, what the ways forward might be.
Arithmetic and dynamical degrees of self-morphisms of semi-abelian varieties
Authors: MATSUZAWA YOHSUKE , SANO KAORU
Published: October 2018

We prove a conjecture by Kawaguchi–Silverman on arithmetic and dynamical degrees, for self-morphisms of semi-abelian varieties. Moreover, we determine the set of the arithmetic degrees of orbits and the (first) dynamical degrees of self-morphisms of semi-abelian varieties.
On the conservative pasting lemma
Authors: TEIXEIRA PEDRO
Published: October 2018

Several perturbation tools are established in the volume-preserving setting allowing for the pasting, extension, localized smoothing and local linearization of vector fields. The pasting and the local linearization hold in all classes of regularity ranging from$C^{1}$to$C^{\infty }$(Hölder included). For diffeomorphisms, a conservative linearized version of Franks’ lemma is proved in the$C^{r,\unicode[STIX]{x1D6FC}}$($r\in \mathbb{Z}^{+}$,$0<\unicode[STIX]{x1D6FC}<1$) and$C^{\infty }$settings, the resulting diffeomorphism having the same regularity as the original one.
Redundant axioms in teaching linear algebra
Authors: Amram Meirav , Dagan Miriam , Levi Sagi , Mouftakhov Artour
Published: October 2018

What is an axiom? The meaning of the term ‘axiom’ varies between different fields of study. In philosophy it means a statement that is accepted without argument, while in physics the term ‘postulate’ is used and it means a theory that was verified in an experiment, and will be considered as true unless it is disproved by other experiments.

In mathematics the notion of ‘axiom’ is used in two related but distinguishable meanings: ‘logical axioms’ and ‘non-logical axioms’. Logical axioms are certain statements that are always true, and from them all tautologies of the language can be derived. Non-logical axioms are statements that are taken to be true, to serve as a premise or starting point for further reasoning and arguments.
Generalising a triangle inequality
Authors: Retkes Zoltan
Published: October 2018

The main goal of this paper is to give a deeper understanding of the geometrical inequality proposed by Martin Lukarevski in [1]. In order to formulate our results we shall introduce and use the following notation throughout this paper. Let A1A2A3 be a triangle a1, a2, a3, the lengths of the sides opposite to A1, A2, A3 respectively, P an arbitrary inner point of it xi, the distance of P from the side of length ai. Let r, R be the inradius and circumradius of the triangle hi, the altitude belonging to side ai, Δ the area and finally let α be a real parameter. We adopt also the use of Σui to refer the sum taken over the suffices i = 1, 2, 3. Now we are in the position to reformulate the original problem into a more general form namely: find bounds for Σxαi in terms of r and R. The main results of our investigation are summarised in the following theorem.
Spindown Polyhedra
Authors: Constantinides Anthony F. , Constantinides George A.
Published: October 2018

Magic: the gathering is a trading card game published by Wizards of the Coast [1]. The aim of most variants of the game is to reduce your opponent's life total from twenty to zero, thus winning the game. As it may take several turns to reduce a player's life total to zero, players need a mechanism to keep track of their current life total. For this purpose, players often use a device called a spindown life counter, shown in Figure 1. A spindown life counter is an icosahedron with a special labelling of the faces, such that − starting with 20 life total − a player can reduce their life total in decrements of one by rolling the icosahedron onto an adjacent face each time. A spindown life counter appears similar to a standard icosahedral die, known in gaming as a d20; however, the labelling of faces is different, as also shown in Figure 1.
Nature-nurture: finding-feeding
Authors: Gardiner Tony
Published: October 2018

Mathematicians know that the path from adolescent competence to adult professional life is full of unexpected twists and turns, and is fraught with potential pitfalls. Even when faced with very able adolescents, it is not at all clear which of them will flourish in the long run, or how one can best support their future development (when they eventually become young adults) in a way that takes their mathematical ability and inclinations seriously – whether in pure or applied mathematics, in computer science or software development, in engineering, mathematical biology, financial mathematics or linguistics, in management, or in some totally different profession.