bluuebunny/crossref_metadata_2025 huggingface dataset:
Does aging‐friendly enhance sustainability? Evidence from Hong Kong
Authors: Qian Queena K. , Ho Winky K.O. , Ochoa J. Jorge , Chan Edwin H.W.
Published: January 2019

The aging population is one of the demographic changes in the 21st century. World Health Organization defines an age‐friendly city as a place that has an “inclusive and accessible urban environment that promotes active aging.” It receives considerable attention in the field of gerontology and contains important aspects of sustainable urban development. Unfortunately, there have not much research that addresses the relationship between aging‐friendly and sustainability. There is a need to modify the market mechanism to achieve environmental objectives while striking a balance between social and economic considerations. This paper aims to empirically examine the integrated relationships between the dense urban environment and the social and emotional needs of the elderly in the Hong Kong context. The on‐street survey was conducted in eight districts in Hong Kong to collect the opinions about aging‐friendly criteria and sustainability indicators. It utilizes principal component analysis and multiple regression technique to unveil the mask of their intrinsic relationship. The empirical results suggest how the aging‐friendly factors have impacted the economic, environmental, and social sustainability to a certain extent. Notably, two key findings were revealed from the empirical results. (a) “Outdoor Spaces” is consistently found not to be a planning factor that can enhance three types of sustainability, irrespective of the age groups in Hong Kong; (b) “Community Support and Health Services” is regarded as a significant factor, with the exception of economic sustainability (age group ≤60).
How Does Azo Bond Cleave in the Gas Phase? Computational and Experimental Study on the Fragmentation Mechanism of Protonated Sudan I
Authors: Qi Ping , Liang Zhi‐an , Wang Ning , Zhao Jin‐Li , Chen Yu‐Zhong , Zhou Qing‐qiong , Gao Hui , Jiang Ji‐Jun
Published: February 2019

As a cheap but harmful additive in food industry, 1‐phenylazo‐2‐naphthol (Sudan I) has attracted lots of attentions, which mainly focused on the determinations using the HPLC‐ESI‐MS/MS techniques. However, the fragmentation mechanisms are generally scarce. In this paper, the fragmentation pathways of protonated Sudan I in gas‐phase were investigated by a combination of electrospray ionization‐tandem mass spectrometry and density functional theory (DFT) calculations. Initially, the cleavage of azo bond is triggered by ionizing proton migration from the oxygen atom of O‐protonated Sudan I to adjacent N atom through a six‐member ring transition state, leading to a single ion‐neutral complex (INC‐s). Subsequently, the direct decomposition of INC‐s gives the naphtol nitrene ion at m/z 156. Meanwhile, INC‐s may occur an intermolecular single electron transfer (SET) reaction via the crossing points (INC‐mecp), affording the triple ion‐neutral complex (INC‐t) consisting of naphtol nitrene radical and aniline radical ion. Finally, followed by the decomposition of INC‐t, the aniline radical ion at m/z 156 is formed. Further studies on Electrostatic potential map, Natural population analysis (NPA) and frontier molecular orbitals (FMOs) during the proposed mechanism are also found to be in good agreement with experimental observations. Taken together, our results presented here not only provide mechanistic information for better understanding the Sudan I, but also give insights into other related harmful additives in food industry.
Effect of Self‐Doped Heteroatoms in Biomass‐Derived Activated Carbon for Supercapacitor Applications
Authors: Chen Dandan , Yang Lijun , Li Jiangfeng , Wu Qingsheng
Published: February 2019

As a green and effective energy storage device, supercapacitors have been attractive due to their high power density along with long cycle stability. Among various electrode materials, carbon materials have drawn significant attention due to their wonderful properties, such as high specific surface area, electronic conductivity, chemical stability and porous structures. In addition, challenges come from global warming and environmental pollution, biomass derived carbon materials feature the concepts of the sustainable development of chemistry. In this, the review not only summarizes the most advanced progress in biomass derived heteroatoms self‐doped carbon materials for supercapacitor, but also provides important guidelines for the future design of biomass‐derived carbons with heteroatoms doping in specific energy applications.
Piezoelectric Microchip for Cell Lysis through Cell–Microparticle Collision within a Microdroplet Driven by Surface Acoustic Wave Oscillation
Authors: Wang Shicai , Lv Xiaoqing , Su Yue , Fan Zhiyuan , Fang Weihao , Duan Jiazhi , Zhang Shan , Ma Baojin , Liu Feng , Chen Hongda , Geng Zhaoxin , Liu Hong
Published: January 2019

Cell lysis is an important and crucial step for the detection of intracellular secrets. Usually, cell lysis is based on strong ultrasonic waves or toxic chemical regents, which require a large amount of cell suspension. To obtain high efficiency cell lysis for a small amount of sample, a mechanical cell lysis method based on a surface acoustic wave (SAW) microchip is proposed. The microchip simply consists of a piece of LiNbO3 crystal substrate, interdigitated transducers (IDTs) with 80 pairs of parallel electrodes and 3M Magic Tapes. The modulated input electrical signal is coupled into the substrate through IDTs, which produces an acoustic stream in the droplet on the surface of a substrate. When a biofluid droplet containing cells and microparticles is dropped on the surface of the microchip, the cells and microparticles are accelerated and collide with each other. The fluorescence staining results illustrate that the cell membrane is efficiently destroyed and that proteins as well as nucleic acids inside the cell are released. The experimental results show that this method has a high efficiency and low sample consumption. The potential application is the pretreatment of a small amount of tested sample in a hospital or biolab.
Efficient and Tunable Electroluminescence from In Situ Synthesized Perovskite Quantum Dots
Authors: Yu Hongling , Wang Heyong , Zhang Jiangbin , Lu Jun , Yuan Zhongcheng , Xu Weidong , Hultman Lars , Bakulin Artem A. , Friend Richard H. , Wang Jianpu , Liu Xiao‐Ke , Gao Feng
Published: January 2019

Semiconductor quantum dots (QDs) are among the most promising next‐generation optoelectronic materials. QDs are generally obtained through either epitaxial or colloidal growth and carry the promise for solution‐processed high‐performance optoelectronic devices such as light‐emitting diodes (LEDs), solar cells, etc. Herein, a straightforward approach to synthesize perovskite QDs and demonstrate their applications in efficient LEDs is reported. The perovskite QDs with controllable crystal sizes and properties are in situ synthesized through one‐step spin‐coating from perovskite precursor solutions followed by thermal annealing. These perovskite QDs feature size‐dependent quantum confinement effect (with readily tunable emissions) and radiative monomolecular recombination. Despite the substantial structural inhomogeneity, the in situ generated perovskite QDs films emit narrow‐bandwidth emission and high color stability due to efficient energy transfer between nanostructures that sweeps away the unfavorable disorder effects. Based on these materials, efficient LEDs with external quantum efficiencies up to 11.0% are realized. This makes the technologically appealing in situ approach promising for further development of state‐of‐the‐art LED systems and other optoelectronic devices.
Locally Trapping the C‐C Chemokine Receptor Type 7 by Gene Delivery Nanoparticle Inhibits Lymphatic Metastasis Prior to Tumor Resection
Authors: An Sai , Tiruthani Karthik , Wang Ying , Xu Ligeng , Hu Mengying , Li Jingjing , Song Wantong , Jiang Hongnan , Sun Jirui , Liu Rihe , Huang Leaf
Published: January 2019

Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Currently, no targeted treatment is available for TNBC, and the most common clinical therapy is tumor resection, which often promotes metastasis risks. Strong evidence suggests that the lymphatic metastasis is mediated by the C‐C chemokine receptor type 7 (CCR7)/C‐C motif chemokine ligand 21 crosstalk between tumor cells and the lymphatic system. It is hypothesized that CCR7 is a key immune modulator in the tumor microenvironment and the local blockade of CCR7 could effectively inhibit TNBC lymphatic metastasis. Accordingly, a plasmid encoding an antagonistic CCR7 affinity protein‐CCR7 trap is delivered by tumor targeting nanoparticles in a highly metastatic 4T1 TNBC mouse model. Results show that CCR7 traps are transiently expressed, locally disrupt the signaling pathways in the tumor site, and efficiently inhibit TNBC lymphatic metastasis, without inducing immunosuppression as observed in systemic therapies using CCR7 monoclonal antibody. Significantly, upon applying CCR7 trap therapy prior to tumor resection, a 4T1 TNBC mouse model shows good prognosis without any further metastasis and relapse. In addition, CCR7 trap therapy efficiently inhibits the lymphatic metastasis in a B16F10 melanoma mouse model, indicating its great potential for various metastatic diseases treatment.
Super‐Stable, Highly Efficient, and Recyclable Fibrous Metal–Organic Framework Membranes for Precious Metal Recovery from Strong Acidic Solutions
Authors: Liu Yang , Lin Shuo , Liu Yanan , Sarkar Amit Kumar , Bediako John Kwame , Kim Hak Yong , Yun Yeoung‐Sang
Published: January 2019

Precious metals such as palladium (Pd) and platinum (Pt) are marvelous materials in the fields of electronic and catalysis, but they are tapering day by day. Zr(IV)‐based metal–organic frameworks (MOFs) are competent for their recovery, notably in harsh environments, while the general powder form limits their practical application. Porous MOF‐based membranes with ultraefficient metal ion permeation, strong stability, and high selectivity are, therefore, strikingly preferred. Herein, a set of polymeric fibrous membranes incorporated with the UiO‐66 series are fabricated; their adsorption/desorption capabilities toward Pd(II) and Pt(IV) are evaluated from strongly acidic solutions; and the MOF–polymer compatibilities are investigated. Polyurethane (PU)/UiO‐66‐NH2 showed strong acid resistance and high chemical stability, which are attributable to strong π–π interactions between PU and MOF nanoparticles with a high configuration of energy. The as‐fabricated MOF membranes show extremely good adsorption/desorption performances without ruptures/coalitions of nanofibers or leak of MOF nanoparticles, and successfully display the efficacy in a gravity‐driven or even continuous‐flow system with good recycle performance and selectivity. The as‐fabricated MOF membranes set an example of potential MOF–polymer compatibility for practical applications.
“Jesus Would Turn the Tables Over”: Five Dimensions of Authenticity Applied to Countercultural Christianity
Authors: Fuist Todd Nicholas , McDowell Amy D.
Published: January 2019

This paper draws on extant literature to identify five dimensions that are deployed by a wide range of social groups to claim and achieve authenticity in variety of social settings: being honest or real, forgoing external rewards or compensation, coming from or living in the right place or time, embodying or participating in something, and consuming correctly. We then demonstrate the utility of these five dimensions of authenticity in action by applying them to two different qualitative studies of countercultural Christians. Our analysis of these data shows that different communities have different understandings of what makes one authentic, but the five dimensions that we outline in this article make comparisons across different groups possible.
Teachers' framing of argumentation goals: Working together to develop individual versus communal understanding
Authors: González‐Howard María , McNeill Katherine L.
Published: January 2019

For students to meaningfully engage in science practices, substantive changes need to occur to deeply entrenched instructional approaches, particularly those related to classroom discourse. Because teachers are critical in establishing how students are permitted to interact in the classroom, it is imperative to examine their role in fostering learning environments in which students carry out science practices. This study explores how teachers describe, or frame, expectations for classroom discussions pertaining to the science practice of argumentation. Specifically, we use the theoretical lens of a participation framework to examine how teachers emphasize particular actions and goals for their students' argumentation. Multiple‐case study methodology was used to explore the relationship between two middle school teachers' framing for argumentation, and their students' engagement in an argumentation discussion. Findings revealed that, through talk moves and physical actions, both teachers emphasized the importance of students driving the argumentation and interacting with peers, resulting in students engaging in various types of dialogic interactions. However, variation in the two teachers' language highlighted different purposes for students to do so. One teacher explained that through these interactions, students could learn from peers, which could result in each individual student revising their original argument. The other teacher articulated that by working with peers and sharing ideas, classroom members would develop a communal understanding. These distinct goals aligned with different patterns in students' argumentation discussion, particularly in relation to students building on each other's ideas, which occurred more frequently in the classroom focused on communal understanding. The findings suggest the need to continue supporting teachers in developing and using rich instructional strategies to help students with dialogic interactions related to argumentation. This work also sheds light on the importance of how teachers frame the goals for student engagement in this science practice.
Ultimate load design of jacket‐type offshore wind turbines under tropical cyclones
Authors: Ju Shen‐Haw , Su Feng‐Chien , Jiang Yao‐Ting , Chiu Yu‐Chuan
Published: January 2019

Tropical cyclones are a high risk to offshore wind turbine (OWT) support structures, so the design conditions, including this risk, are necessary for tropical cyclone frequent occurrence zones. This study developed a computer program to carry out a critical ultimate load analysis and determine the optimum design for a Jacket‐type OWT support structure. The total weight of the OWT support structure after the optimal steel design with the yaw operative condition is always considerably smaller than that without for the steel design results under the loads of the GL Tropical Cyclone Technical Note (GL TCTN). This paper studies OWTs under the tropical cyclone classes 1 to 3 and the terrain categories A, to C, where the 1‐minute wind speed at 10‐m height is gradually increased from classes 1 to 3, and the surface roughness decreases from A to C. When the yaw can operate, the total steel weight consumption due to the tropical cyclone 1C, 1B, and 2C loads is lower than that for the IEC 61400‐3 loads. In the case of 1A, the overall steel consumption is only slightly higher than that of the IEC 61400‐3. However, for other conditions, the design should include the GL TCTN loads. For the yaw inoperative condition, the GL TCTN results are always largely dominant in the steel design, so the use of only the IEC 61400‐3 condition will result in extremely high risk to OWT support structures.
Thermodynamic equilibrium predictions of zinc volatilization, migration, and transformation during sludge co‐incineration
Authors: Liu Jingyong , Cai Haiming , Wu Shijun , Dang Xiaoe , Buyukada Musa , Evrendilek Fatih
Published: January 2019

The effects of interactions between and among chlorine (Cl), sulfur (S), phosphorus (P), and minerals on migration, transformation, and volatilization of zinc (Zn) were numerically simulated in sludge co‐incineration using the chemical thermodynamic equilibrium method. Our results showed that all the minerals of Fe2O3, Al2O3, Fe2O3, and TiO2 except for CaO in the sludge co‐incineration system reacted with Zn which inhibited the Zn volatilization. The presence of S and P was beneficial to the formation of ZnSO4(s) and Zn3(PO4)2(s). Cl weakened the chemical reactions between the minerals and Zn, thus increasing the Zn volatilization. Changes in Zn transformation and migration induced by the coupling of Cl + S were mainly controlled by Cl, S, and the minerals, while those induced by Cl + P and S + P were mainly controlled by P and S + P. The presence of P + Cl, S + Cl, S + P, S + Cl + P, Cl, and Al2O3 in the coexisting mineral system controlled the reactions between the minerals and Zn.
Impacts of solids retention time and antibiotic loading in activated sludge systems on secondary effluent water quality and microbial community structure
Authors: Gerrity Daniel , Neyestani Majid
Published: January 2019

Solids retention time (SRT) is one of the most important factors in designing and operating activated sludge systems for biological wastewater treatment. Longer SRTs have been shown to alter the structure and function of microbial communities, thereby leading to improved treatment efficacy with respect to bulk and trace organics, nutrient removal, and membrane fouling. Research has also shown that longer SRTs and/or higher influent antibiotic concentrations may lead to increased prevalence of antibiotic resistance. However, it is unclear whether elevated, yet subclinical, concentrations of antibiotics also impact the overall microbial community. The purpose of this study was to characterize changes in microbial community structure in a laboratory‐scale activated sludge system as a function of SRT (2–20 days) and influent concentrations (1×–100× ambient) of ampicillin, sulfamethoxazole, tetracycline, trimethoprim, and vancomycin. Changes in microbial community structure were evaluated based on 16S rRNA gene sequencing, and microbial community function was evaluated based on changes in effluent water quality, including attenuation of bulk and trace organics. The results confirmed that longer SRTs—but not antibiotic loadings—had a significant impact on microbial community structure and effluent water quality. Therefore, moderate spikes in influent antibiotic concentrations are not expected to adversely impact biological wastewater treatment.

Practitioner points

Longer SRTs lead to changes in microbial community structure, including alpha and beta diversity and relative abundance of various taxa.

Enhanced TOrC attenuation at longer SRTs may be linked to biomass abundance rather than changes in microbial community structure.

Moderate spikes in influent antibiotic concentrations do not impact activated sludge performance or microbial community structure.

The phyla Proteobacteria and Bacteroidetes comprise a majority of the microbial community in primary effluent and mixed liquor.
Symmetry breaking in quantum curves and super Chern-Simons matrix models
Authors: Kubo Naotaka , Moriyama Sanefumi , Nosaka Tomoki
Published: January 2019

Abstract

It was known that quantum curves and super Chern-Simons matrix models correspond to each other. From the viewpoint of symmetry, the algebraic curve of genus one, called the del Pezzo curve, enjoys symmetry of the exceptional algebra, while the super Chern-Simons matrix model is described by the free energy of topological strings on the del Pezzo background with the symmetry broken. We study the symmetry breaking of the quantum cousin of the algebraic curve and reproduce the results in the super Chern-Simons matrix model.
On the relationship between gauge dependence and IR divergences in the ℏ-expansion of the effective potential
Authors: Ekstedt Andreas , Löfgren Johan
Published: February 2019

Abstract

Perturbative calculations of the effective potential evaluated at a broken minimum, V
min, are plagued by difficulties. It is hard to get a finite and gauge invariant result for V
min. In fact, the methods proposed to deal with gauge dependence and ir divergences are orthogonal in their approaches. Gauge dependence is dealt with through the ℏ-expansion, which establishes and maintains a strict loop-order separation of terms. On the other hand, ir divergences seem to require a resummation that mixes the different loop orders. In this paper we test these methods on Fermi gauge Abelian Higgs at two loops. We find that the resummation procedure is not capable of removing all divergences. Surprisingly, the ℏ-expansion seems to be able to deal with both the divergences and the gauge dependence. In order to isolate the physical part of V
min, we are guided by the separation of scales that motivated the resummation procedure; the key result is that only hard momentum modes contribute to V
min.
Computational methods and applications for quantitative systems pharmacology
Authors: Xie Fuda , Gu Jiangyong
Published: January 2019

Background

Quantitative systems pharmacology (QSP) is an emerging discipline that integrates diverse data to quantitatively explore the interactions between d
rugs and multi‐scale systems including small compounds, nucleic acids, proteins, pathways, cells, organs and disease processes.

Results

Various computational methods such as ADME/T evaluation, molecular modeling, logical modeling, network modeling, pathway analysis, multi‐scale systems pharmacology platforms and virtual patient for QSP have been developed. We reviewed the major progresses and broad applications in medical guidance, drug discovery and exploration of pharmacodynamic material basis and mechanism of traditional Chinese medicine.

Conclusion

QSP has significant achievements in recent years and is a promising approach for quantitative evaluation of drug efficacy and systematic exploration of mechanisms of action of drugs.
Regular variation in a fixed-point problem for single- and multi-class branching processes and queues
Authors: Asmussen Søren , Foss Sergey
Published: February 2019

Tail asymptotics of the solution R to a fixed-point problem of the type R=DQ+∑1NRm are derived under heavy-tailed conditions allowing both dependence between Q and N and the tails to be of the same order of magnitude. Similar results are derived for a K-class version with applications to multi-type branching processes and busy periods in multi-class queues.
Between Order and Justice: Investments in Africa and Corporate International Responsibility in Swedish Media in the 1960s
Authors: GLOVER NIKOLAS
Published: January 2019

This article analyzes how the public relations of multinational companies was affected by the double impact of decolonization and spread of television during the 1960s. It contributes to recent theoretical conceptualizations of corporate social responsibility by adding the dimension of home country stakeholders and the border-crossing character of corporate responsibility. The analysis deals with the changing media representations in Sweden of Swedish-owned firms in Liberia and South Africa before, during, and after what has been called the “postcolonial moment” (1960–1963). In its wake, Swedish industrialists faced a new policy problem: firms in overseas markets were no longer expected to do only what was legal in the host country but also what was considered right in their home country. The analysis follows the debates concerning this issue of corporateinternationalresponsibility throughout the 1960s, and how national business organizations and executives in firms such as the Liberian-American-Swedish Mining Company publicly sought to defend the role of Swedish foreign direct investment in Africa. The business community developed various public relations strategies to engage with its critics, professionalized their media relations, and organized international study tours for unions and politicians.
MONOID ACTIONS AND ULTRAFILTER METHODS IN RAMSEY THEORY
Authors: SOLECKI SŁAWOMIR
Published: January 2019

First, we prove a theorem on dynamics of actions of monoids by endomorphisms of semigroups. Second, we introduce algebraic structures suitable for formalizing infinitary Ramsey statements and prove a theorem that such statements are implied by the existence of appropriate homomorphisms between the algebraic structures. We make a connection between the two themes above, which allows us to prove some general Ramsey theorems for sequences. We give a new proof of the Furstenberg–Katznelson Ramsey theorem; in fact, we obtain a version of this theorem that is stronger than the original one. We answer in the negative a question of Lupini on possible extensions of Gowers’ Ramsey theorem.
Pump or coast: the role of resonance and passive energy recapture in medusan swimming performance
Authors: Hoover Alexander P. , Porras Antonio J. , Miller Laura A.
Published: January 2019

Diverse organisms that swim and fly in the inertial regime use the flapping or pumping of flexible appendages and cavities to propel themselves through a fluid. It has long been postulated that the speed and efficiency of locomotion are optimized by oscillating these appendages at their frequency of free vibration. In jellyfish swimming, a significant contribution to locomotory efficiency has been attributed to the effects passive energy recapture, whereby the bell is passively propelled through the fluid through its interaction with stopping vortex rings formed during each expansion of the bell. In this paper, we investigate the interplay between resonance and passive energy recapture using a three-dimensional implementation of the immersed boundary method to solve the fluid–structure interaction of an elastic oblate jellyfish bell propelling itself through a viscous fluid. The motion is generated through a fixed duration application of active tension to the bell margin, which mimics the action of the coronal swimming muscles. The pulsing frequency is then varied by altering the length of time between the application of applied tension. We find that the swimming speed is maximized when the bell is driven at its resonant frequency. However, the cost of transport is maximized by driving the bell at lower frequencies whereby the jellyfish passively coasts between active contractions through its interaction with the stopping vortex ring. Furthermore, the thrust generated by passive energy recapture was found to be dependent on the elastic properties of the jellyfish bell.
Weakly nonlinear transient waves on a shear current: ring waves and skewed Langmuir rolls
Authors: Akselsen Andreas H. , Ellingsen Simen Å.
Published: January 2019

We investigate the weakly nonlinear dynamics of transient gravity waves at infinite depth under the influence of a shear current varying linearly with depth. The shear field makes this problem three-dimensional and rotational in nature, but an analytical solution is permitted via integration of the Euler equations. Although similar problems were investigated in the 1960s and 70s for special cases of resonance, this is to our knowledge the first general wave interaction (mode coupling) solution derived to second order with a shear current present. Wave interactions are integrable in a spectral convolution to yield the second-order dynamics of initial value problems. To second order, irrotational wave dynamics interacts with the background vorticity field in a way that creates new vortex structures. A notable example is the large parallel vortices which drive Langmuir circulation as oblique plane waves interact with an ocean current. We also investigate the effect on wave pairs which are misaligned with the shear current to find that similar, but skewed, vortex structures are generated in every case except when the mean wave direction is precisely perpendicular to the direction of the current. This is in contrast to a conjecture by Leibovich (Annu. Rev. Fluid Mech., vol. 15, 1983, pp. 391–427). Similar nonlinear wave–shear interactions are found to also generate near-field vortex structures in the Cauchy–Poisson problem with an initial surface elevation. These interactions create further groups of dispersive ring waves in addition to those present in linear theory. The second-order solution is derived in a general manner which accommodates any initial condition through mode coupling over a continuous wave spectrum. It is therefore applicable to a range of problems including special cases of resonance. As a by-product of the general theory, a simple expression for the Stokes drift due to a monochromatic wave propagating at oblique angle with a current of uniform vorticity is derived, for the first time to our knowledge.
On the unsteady characteristics of turbulent separations over a forward–backward-facing step
Authors: Fang Xingjun , Tachie Mark F.
Published: January 2019

Turbulent separation bubbles over and behind a two-dimensional forward–backward-facing step submerged in a deep turbulent boundary layer are investigated using a time-resolved particle image velocimetry. The Reynolds number based on the step height and free-stream velocity is 12 300, and the ratio of the streamwise length to the height of the step is 2.36. The upstream turbulent boundary layer thickness is 4.8 times the step height to ensure a strong interaction of the upstream turbulence structures with the separated shear layers over and behind the step. The velocity measurements were performed in streamwise–vertical planes at the channel mid-span and streamwise–spanwise planes at various vertical distances from the wall. The unsteady characteristics of the separation bubbles and their associated turbulence structures are studied using a variety of techniques including linear stochastic estimation, proper orthogonal decomposition and variable-interval time averaging. The results indicate that the low-frequency flapping motion of the separation bubble over the step is induced by the oncoming large-scale alternating low- and high-velocity streaky structures. Dual separation bubbles appear periodically over the step at a higher frequency than the flapping motion, and are attributed to the inherent instability in the rear part of the mean separation bubble. The separation bubble behind the step exhibits a flapping motion at the same frequency as the separation bubble over the step, but with a distinct phase delay. At instances when an enlarged separation bubble is formed in front of the step, a pair of vertical counter-rotating vortices is formed in the immediate vicinity of the leading edge.
What Can Instrumental Variables Tell Us About Nonresponse In Household Surveys and Political Polls?
Authors: Wing Coady
Published: January 2019

This paper introduces an instrumental variables framework for analyzing how external factors that affect survey response rates can also affect the composition of the sample of respondents. The method may be useful for studying survey representativeness, and for assessing the effectiveness of some of the conventional corrections for survey nonresponse bias.

The paper applies the method to data collected in the 2011 Swiss Electoral Study (SES), in which survey participation incentives were randomly assigned across members of the original survey sample. The empirical analysis shows that the incentives increased response rates substantially. Estimates of a new instrumental variable parameter called the Complier Average Survey Response (CASR) suggest that the incentives induced participation among people with more nationalist political opinions than those who would have participated without the incentives. Weighting the respondent data to match the covariate distribution in the target population did not account for the discrepancy in attitudes between the two groups, suggesting that the weights would not succeed in removing nonresponse bias.
Determinantal inequalities for the partition function
Authors: Jia Dennis X.Q. , Wang Larry X.W.
Published: January 2019

Letp(n) denote the partition function. In this paper, we will prove that for$n\ges 222$,$$\left| {\matrix{ {p(n)} & {p(n + 1)} & {p(n + 2)} \cr {p(n-1)} & {p(n)} & {p(n + 1)} \cr {p(n-2)} & {p(n-1)} & {p(n)} \cr } } \right| > 0.{\rm }$$As a corollary, we deduce thatp(n) satisfies the double Turán inequalities, that is, for$n\ges 222$,$$(p(n)^2-p(n-1)p(n+1))^2-(p(n-1)^2-p(n-2)p(n))(p(n+1)^2-p(n)p(n+2))>0.$$
Liouville-type theorems and existence results for stable solutions to weighted Lane–Emden equations
Authors: Farina Alberto , Hasegawa Shoichi
Published: January 2019

We devote this paper to proving non-existence and existence of stable solutions to weighted Lane-Emden equations on the Euclidean space ℝN, N ⩾ 2. We first prove some new Liouville-type theorems for stable solutions which recover and considerably improve upon the known results. In particular, our approach applies to various weighted equations, which naturally appear in many applications, but that are not covered by the existing literature. A typical example is provided by the well-know Matukuma's equation. We also prove an existence result for positive, bounded and stable solutions to a large family of weighted Lane–Emden equations, which indicates that our Liouville-type theorems are somehow sharp.
On two cohomological Hall algebras
Authors: Yang Yaping , Zhao Gufang
Published: January 2019

We compare two cohomological Hall algebras (CoHA). The first one is the preprojective CoHA introduced in [19] associated with each quiver Q, and each algebraic oriented cohomology theory A. It is defined as the A-homology of the moduli of representations of the preprojective algebra of Q, generalizing the K-theoretic Hall algebra of commuting varieties of Schiffmann-Vasserot [15]. The other one is the critical CoHA defined by Kontsevich-Soibelman associated with each quiver with potentials. It is defined using the equivariant cohomology with compact support with coefficients in the sheaf of vanishing cycles. In the present paper, we show that the critical CoHA, for the quiver with potential of Ginzburg, is isomorphic to the preprojective CoHA as algebras. As applications, we obtain an algebra homomorphism from the positive part of the Yangian to the critical CoHA.
Adaption of body zinc pools in weaned piglets challenged with subclinical zinc deficiency
Authors: Brugger Daniel , Windisch Wilhelm M.
Published: January 2019

The effects of subclinical Zn deficiency on depletion and redistribution of body Zn were studied in weaned piglets. Forty-eight weaned piglets (German-Large-White×Land-Race×Piétrain; 50 % female, 50 % male-castrated; body weight 8·5 (sd0·27) kg) were fed restrictively (450 g/d) a basal maize–soyabean meal-based diet supplemented with varying amounts of ZnSO4.7H2O (analysed dietary Zn: 28·1, 33·6, 38·8, 42·7, 47·5, 58·2, 67·8, 88·0 mg/kg diet) for an experimental period of 8 d. Analyses comprised Zn concentrations in soft tissues. Statistical analyses included regression models andk-means cluster analysis. Jejunum and kidney Zn correlated positively with dietary Zn (P<0·05). Other Zn pools responded in a non-linear fashion by declining (colon, epidermis, spleen) or increasing (mesenteric lymph follicles, thymus, skeletal muscle) below 63·6, 48·0, 47·5, 68·0, 43·0 and 53·1 mg Zn/kg diet, respectively (P<0·01). Above these thresholds, Zn concentrations in epidermis, mesenteric lymph follicles and skeletal muscle plateaued (P<0·0001), whereas they exhibited a decrease in colon and thymus (P<0·01) as well as a numerical increase in spleen. Clustering by dietary Zn concentration indicated clusters of varying Zn supply status and pathophysiological status. Clustering by biological matrices revealed a discrimination between storage, transport and excretion media as well as soft tissues. Taken together, novel response patterns indicated compensation reactions in tissues that are essential for the acute survival of growing animals (heart, skeletal muscle, immune tissues). Furthermore, this is to our knowledge the first study that mapped the gross Zn requirement by clustering tissue Zn concentrations between treatment groups.
Saving ourselves? On rescue and humanitarian action
Authors: Radice Henry
Published: January 2019

This article contributes to the international political theory of humanitarianism by unpicking the politics of humanitarian action’s simplest expression: saving human lives in the name of humanity. Both saving lives and defining notions of common humanity are closely interrelated acts of power. What saving a life means depends on a prior definition of humanity; humanitarians’ acts of rescue are the measure of their commitment to humanity. The politics of rescue and the politics of humanity are inextricably linked. The article explores four facets of this nexus. First, it considers the meanings of rescue, from saving bodies to saving lives, linked to contingent understandings of humanity. Second, it turns to the rescuers, for whom rescue performs particular functions, not least the need to preserve a sense of self. Third, it situates their often narcissistic motives in relation to the consequences of humanitarian action. Fourth, it addresses the power imbalance inherent in rescue and the problem of causing harm. It concludes that rescue is always an act of presumption, but one that can be tempered by humanitarian actors willing to embrace their role as ‘moral politicians’ (Walzer), aware of their power and their dirty hands, and open to contrasting understandings of humanity.
Effects of Anodal Transcranial Direct Current Stimulation (atDCS) on Sentence Comprehension
Authors: Lum Jarrad A. G. , Clark Gillian M. , Rogers Caitlyn M. , Skalkos James D. , Fuelscher Ian , Hyde Christian , Enticott Peter G.
Published: January 2019

Objectives: This study examined the effects of anodal transcranial direct current stimulation (a-tDCS) on sentence and word comprehension in healthy adults. Methods: Healthy adult participants, aged between 19 and 30 years, received either a-tDCS over the left inferior frontal gyrus (n=18) or sham stimulation (n=18). Participants completed sentence comprehension and word comprehension tasks before and during stimulation. Accuracy and reaction times (RTs) were recorded as participants completed both tasks. Results: a-tDCS was found to significantly decrease RT on the sentence comprehension task compared to baseline. There was no change in RT following sham stimulation. a-tDCS was not found to have a significant effect on accuracy. Also, a-tDCS did not affect accuracy or RTs on the word comprehension task. Conclusions: The study provides evidence that non-invasive anodal electrical stimulation can modulate sentence comprehension in healthy adults, at least compared to their baseline performance. (JINS, 2019, 25, 331–335)
Navigating complex financial decisions at retirement: evidence from annuity choices in public sector pensions
Authors: Clark Robert L. , Hammond Robert G. , Vanderweide David
Published: January 2019

Choices regarding the disposition of wealth at retirement can have substantial implications for retirement income security. We analyze the factors determining annuity payout option choices within the context of a public sector defined pension plan with no default annuity option. Using combined administrative records and survey data, we explore the role of individual and household characteristics as well as risk preferences, time preferences, and financial literacy. We also document retiree well-being and satisfaction with retirement decision making. The evidence is consistent with predictions over which households might benefit most from each annuity option. Comparing retirees who chose different types of annuities, we find that these groups of retirees report very different levels of well-being in retirement. All retirees report lower levels of retirement income security over time, with strong differences among those who chose different types of annuities.
Merging massive black holes the right place and the right time
Authors: Lamberts Astrid
Published: January 2019

The LIGO/Virgo detections of gravitational waves from merging black holes of ≃ 30 solar mass suggest progenitor stars of low metallicity (Z/Z⊙≲ 0.3). In this talk I will provide constrains on where the progenitors of GW150914 and GW170104 may have formed, based on advanced models of galaxy formation and evolution combined with binary population synthesis models. First I will combine estimates of galaxy properties (star-forming gas metallicity, star formation rate and merger rate) across cosmic time to predict the low redshift BBH merger rate as a function of present day host galaxy mass, formation redshift of the progenitor system and different progenitor metallicities. I will show that the signal is dominated by binaries formed at the peak of star formation in massive galaxies with and binaries formed recently in dwarf galaxies. Then, I will present what very high resolution hydrodynamic simulations of different galaxy types can learn us about their black hole populations.
How Einstein’s Theory of Relativity Gives us and the Atomic Bomb
Authors: Henry Richard Conn
Published: January 2019

The LIGO direct-detection of gravitational waves arriving from cosmic sources—now, happily including (as of this meeting!) the merging of two neutron stars—opens a new chapter in our understanding of physics itself: for General Relativity, conceptually so extremely simple, has robustly produced predictions that have invariably been found to be correct when tested. My poster (page 3 of this paper) is intended for high school students who have just learned simple algebra. My derivation of the famous E = mc2 from the Pythagorean Theorem necessarily requires an algebraic expansion that is due to Newton, but apart from that it is simplicity itself: a transparent introduction to what all of physics is today: the construction of mathematics that, miraculously, reproduces our observations of the world—and which also successfully predicts the results of future observations—as so magnificently demonstrated at this glorious Symposium!
DESGW Optical Follow-up of BBH LIGO-Virgo Events with DECam
Authors: Butler Robert E. , Soares-Santos M. , Annis J. , Herner K. ,   for the Dark Energy Survey Gravitational Wave program and the DECam Community Group Collaboration
Published: January 2019

The DESGW program is a collaboration between members of the Dark Energy Survey, the wider astronomical community, and the LIGO-Virgo Collaboration to search for optical counterparts of gravitational wave events, such as those expected from binary neutron star mergers or neutron star-black hole mergers. While binary black hole (BBH) events are not expected to produce an electromagnetic (EM) signature, emission is certainly not impossible. The DESGW program has performed follow-up observations of four BBH events detected by LIGO in order to search for any possible EM counterpart. Failure to find such counterparts is still relevant in that it produces limits on optical emission from such events. This is a review of follow-up results from O1 BBH events and a discussion of the status of ongoing uniform re-analysis of all BBH events that DESGW has followed up to date.
Strong-lensing of Gravitational Waves by Galaxy Clusters
Authors: Smith Graham P. , Berry Christopher , Bianconi Matteo , Farr Will M. , Jauzac Mathilde , Massey Richard , Richard Johan , Robertson Andrew , Sharon Keren , Vecchio Alberto , Veitch John
Published: January 2019

Discovery of strongly-lensed gravitational wave (GW) sources will unveil binary compact objects at higher redshifts and lower intrinsic luminosities than is possible without lensing. Such systems will yield unprecedented constraints on the mass distribution in galaxy clusters, measurements of the polarization of GWs, tests of General Relativity, and constraints on the Hubble parameter. Excited by these prospects, and intrigued by the presence of so-called “heavy black holes” in the early detections by LIGO-Virgo, we commenced a search for strongly-lensed GWs and possible electromagnetic counterparts in the latter stages of the second LIGO observing run (O2). Here, we summarise our calculation of the detection rate of strongly-lensed GWs, describe our review of BBH detections from O1, outline our observing strategy in O2, summarize our follow-up observations of GW170814, and discuss the future prospects of detection.
High power in Advanced LIGO
Authors: Hardwick Terra ,   for the LIGO Scientific Collaboration
Published: January 2019

The LIGO detectors have just completed a successful and exciting observation run. Both facilities are now undergoing upgrades and commissioning, including doubling the circulating power in the interferometer which will increase LIGO’s sensitivity above 100 Hz. This paper motivates the power increase and discusses the problems in general that arise with higher power and the progress to date with addressing them. Topics include input power noise coupling, parametric instability, and thermal effects.
CHAPTER VIII: NEW MEMBERS AND DECEASED MEMBERS AT THE GENERAL ASSEMBLY
Authors: Heap Sara R. , Henkel Christian , Im Myungshin , Kaper Lex , Méndez Bussard Rene A. , Rucker Helmut O. , Samus Nikolay N. , Sefako Ramotholo R.
Published: January 2019

Activities started in early 2015. Individuals applying for nomination for IAU Individual Membership should have contacted their NCA or Adhering Organization before December 1, 2014. The deadline for approved nominations for Individual Members to be submitted to the IAU Secretariat by NCAs or Adhering Organizations was February 3, 2015. Therefore, the focus of this report are the last months prior to the IAU XXIX General Assembly (August 2015) in Honolulu.
Vegetation and Climate Change in Southwestern Australia During the Last Glacial Maximum
Authors: Sniderman J. M. K. , Hellstrom J. , Woodhead J. D. , Drysdale R. N. , Bajo P. , Archer M. , Hatcher L.
Published: January 2019

The nature and duration of the Last Glacial Maximum (LGM) in Australia are poorly understood, with little regional agreement on the timing and direction of LGM climate changes. One reason for this is that Australian Late Pleistocene terrestrial sediments typically are both sparse and inorganic, inhibiting the development of detailed radiocarbon chronologies. To address this problem, we extracted fossil pollen from radiometrically dated stalagmites collected in southwest Western Australia. Our pollen record, supported by 30 U‐Th dates, reveals the vegetation response to Late Pleistocene climates between ~34 and 14 ka, through the body of the LGM. Before ~28 ka, sclerophyll forests were more open than today, but at ~28 ka forest cover was essentially eliminated, and treeless conditions were maintained until progressive reforestation at ~17.5 ka. This ~10‐ka‐long full glacial episode correlates with other mid‐high latitude Southern Hemisphere records, suggesting that LGM environmental changes were closely coordinated across the hemisphere.
The Potential of DAS in Teleseismic Studies: Insights From the Goldstone Experiment
Authors: Yu Chunquan , Zhan Zhongwen , Lindsey Nathaniel J. , Ajo‐Franklin Jonathan B. , Robertson Michelle
Published: January 2019

Distributed acoustic sensing (DAS) is a recently developed technique that has demonstrated its utility in the oil and gas industry. Here we demonstrate the potential of DAS in teleseismic studies using the Goldstone OpticaL Fiber Seismic experiment in Goldstone, California. By analyzing teleseismic waveforms from the 10 January 2018 M7.5 Honduras earthquake recorded on ~5,000 DAS channels and the nearby broadband station GSC, we first compute receiver functions for DAS channels using the vertical‐component GSC velocity as an approximation for the incident source wavelet. The Moho P‐to‐s conversions are clearly visible on DAS receiver functions. We then derive meter‐scale arrival time measurements along the entire 20‐km‐long array. We are also able to measure path‐averaged Rayleigh wave group velocity and local Rayleigh wave phase velocity. The latter, however, has large uncertainties. Our study suggests that DAS will likely play an important role in many fields of passive seismology in the near future.