bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling and optimization of flat plate solar air collectors: An integrated fuzzy method
Authors: Debnath S. , Reddy J. , Das B. , Jagadish
Published: August 2019

The modeling and optimization of a flat plate solar air collector are investigated experimentally under the climatic conditions of Northeastern India using the integrated fuzzy method (IFM). The IFM consists of a combined subtractive clustering with a fuzzy (Takagi-Kang) method. The subtractive technique is used to find the most favorable IF-THEN rules while the fuzzy method is to optimize/predict the solar air collector parameters. Various governing parameters, such as the mass flow rate of air, collector tilt angle, solar radiation, and ambient temperature, are used as the input parameters while the thermal efficiency, exergetic efficiency, temperature rise, and pressure drop are the output parameters. First, experiments on solar air collectors are performed by varying the input parameters. Then, optimization, prediction, and parametric analyses are conducted. Finally, the proposed results are validated using confirmatory tests with the experimental data, published data, and artificially generated data. The accuracy of the obtained result for the solar air collector is found to be ∼97.5% and the best possible set of governing parameters are a mass flow rate of 0.00785 kg/s, tilt angle of 45°, solar radiation of 450 W/m2, and a temperature of 27 °C. The corresponding outputs are the efficiency at 28.88% and the exergetic efficiency at 5.15%.
Well-posedness and blow-up solution for the stochastic Dullin-Gottwald-Holm equation
Authors: Lv Wujun , He Ping , Wang Qinghua
Published: August 2019

In this paper, to describe the uncertainty from external environment, we propose a stochastic Dullin-Gottwald-Holm (SDGH) equation by adding an additive noise to the well-known DGH equation. Using regularization, the local existence and uniqueness of the solution of SDGH are proved. By means of a priori estimates, we find that the local solution may blow up in a finite time if the initial value satisfies certain conditions.
A new fractional model and optimal control of a tumor-immune surveillance with non-singular derivative operator
Authors: Baleanu D. , Jajarmi A. , Sajjadi S. S. , Mozyrska D.
Published: August 2019

In this paper, we present a new fractional-order mathematical model for a tumor-immune surveillance mechanism. We analyze the interactions between various tumor cell populations and immune system via a system of fractional differential equations (FDEs). An efficient numerical procedure is suggested to solve these FDEs by considering singular and nonsingular derivative operators. An optimal control strategy for investigating the effect of chemotherapy treatment on the proposed fractional model is also provided. Simulation results show that the new presented model based on the fractional operator with Mittag–Leffler kernel represents various asymptomatic behaviors that tracks the real data more accurately than the other fractional- and integer-order models. Numerical simulations also verify the efficiency of the proposed optimal control strategy and show that the growth of the naive tumor cell population is successfully declined.
Network structure effects in reservoir computers
Authors: Carroll T. L. , Pecora L. M.
Published: August 2019

A reservoir computer is a complex nonlinear dynamical system that has been shown to be useful for solving certain problems, such as prediction of chaotic signals, speech recognition, or control of robotic systems. Typically, a reservoir computer is constructed by connecting a large number of nonlinear nodes in a network, driving the nodes with an input signal and using the node outputs to fit a training signal. In this work, we set up reservoirs where the edges (or connections) between all the network nodes are either +1 or 0 and proceed to alter the network structure by flipping some of these edges from +1 to −1. We use this simple network because it turns out to be easy to characterize; we may use the fraction of edges flipped as a measure of how much we have altered the network. In some cases, the network can be rearranged in a finite number of ways without changing its structure; these rearrangements are symmetries of the network, and the number of symmetries is also useful for characterizing the network. We find that changing the number of edges flipped in the network changes the rank of the covariance of a matrix consisting of the time series from the different nodes in the network and speculate that this rank is important for understanding the reservoir computer performance.
Effect of polymer-coated gold nanoparticle stabilizers on drop coalescence
Authors: Vannozzi Carolina
Published: August 2019

Polymer-coated gold nanoparticles (PGNPs) can be used as stabilizers in immiscible polymer blends, similar to block-copolymers (BCs). However, the PGNP gold cores increase the magnitude of the disjoining pressure (Π), i.e., the van der Waals interaction for unit area, in the film between the drops, favoring coalescence. This might explain the counterintuitive 70% drainage time (td) reduction for polymeric drops stabilized by PGNPs compared to those stabilized by BCs, as reported in recent flow-induced head-on collision experiments in extensional flow, despite PGNPs being more surface active. Knowledge of the mechanisms determining td is fundamental for designing effective PGNP compatibilizers. Here, we performed a parametric study of those experiments via boundary integral simulations, treating PGNPs as surfactants and utilizing for the first time a disjoining pressure expression which includes the effect of interfacial PGNPs (ΠPGNP). In particular, we varied the PGNP concentration and core size in ΠPGNP, the surface diffusivity (Ds) via the surface Peclet number, and the surface elasticity via the Marangoni number. Flow-induced coalescence was very sensitive to all three parameters. td was reduced up to 60% for touching 3 nm core diameter PGNPs, increasing significantly the coalescence probability for drop sizes <5 µm, but the soft coronas diminished this effect considerably. Thus, other causes, besides the enhanced Π, had to be simultaneously present to explain the dramatic experimental td reduction; the most likely is a Ds higher than its Stokes-Einstein relation estimate and the PGNP ligands being in a dry-brush regime, leading to entropic attraction between the drop interfaces.
Piston driven converging shock waves in a stiffened gas
Authors: Ramsey Scott D. , Baty Roy S.
Published: August 2019

The problem of a one-dimensional (1D) cylindrically or spherically symmetric shock wave converging into an inviscid, ideal gas was first investigated by Guderley[Starke kugelige und zylinrische verdichtungsstosse in der nahe des kugelmitterpunktes bzw. Der zylinderachse,” Luftfahrtforschung 19, 302 (1942)]. In the time since, many authors have discussed the practical notion of how Guderley-like flows might be generated. One candidate is a constant velocity, converging “cylindrical or spherical piston,” giving rise to a converging shock wave in the spirit of its classical, planar counterpart. A limitation of pre-existing analyses along these lines is the restriction to flows in materials described by an ideal gas equation of state (EOS) constitutive law. This choice is of course necessary for the direct comparison with the classical Guderley solution, which also features an ideal gas EOS. However, the ideal gas EOS is limited in its utility in describing a wide variety of physical phenomena and, in particular, the shock compression of solid materials. This work is thus intended to provide an extension of previous work to a nonideal EOS. The stiff gas EOS is chosen as a logical starting point due to not only its close resemblance to the ideal gas law but also its relevance to the shock compression of various liquid and solid materials. Using this choice of EOS, the solution of a 1D planar piston problem is constructed and subsequently used as the lowest order term in a quasi-self-similar series expansion intended to capture both curvilinear and nonideal EOS effects. The solution associated with this procedure provides correction terms to the 1D planar solution so that the expected accelerating shock trajectory and nontrivially varying state variable profiles can be obtained. This solution is further examined in the limit as the converging shock wave approaches the 1D curvilinear origin. Given the stiff gas EOS is not otherwise expected to admit a Guderley-like solution when coupled to the inviscid Euler equations, this work thus provides the semianalytical limiting behavior of a flow that cannot be otherwise captured using self-similar analysis.
Network inference from the timing of events in coupled dynamical systems
Authors: Hassanibesheli Forough , Donner Reik V.
Published: August 2019

Spreading phenomena like opinion formation or disease propagation often follow the links of some underlying network structure. While the effects of network topology on spreading efficiency have already been vastly studied, we here address the inverse problem of whether we can infer an unknown network structure from the timing of events observed at different nodes. For this purpose, we numerically investigate two types of event-based stochastic processes. On the one hand, a generic model of event propagation on networks is considered where the nodes exhibit two types of eventlike activity: spontaneous events reflecting mutually independent Poisson processes and triggered events that occur with a certain probability whenever one of the neighboring nodes exhibits any of these two kinds of events. On the other hand, we study a variant of the well-known SIRS model from epidemiology and record only the timings of state switching events of individual nodes, irrespective of the specific states involved. Based on simulations of both models on different prototypical network architectures, we study the pairwise statistical similarity between the sequences of event timings at all nodes by means of event synchronization and event coincidence analysis (ECA). By taking strong mutual similarities of event sequences (functional connectivity) as proxies for actual physical links (structural connectivity), we demonstrate that both approaches can lead to reasonable prediction accuracy. In general, sparser networks can be reconstructed more accurately than denser ones, especially in the case of larger networks. In such cases, ECA is shown to commonly exhibit the better reconstruction accuracy.
The role of Mg bulk hyper-doping and delta-doping in low-resistance GaN homojunction tunnel diodes with negative differential resistance
Authors: Vadiee Ehsan , Clinton Evan A. , Carpenter Joe V. , McFavilen Heather , Arena Chantal , Holman Zachary C. , Honsberg Christiana B. , Doolittle W. Alan
Published: August 2019

GaN p++/n++ tunnel junctions (TJs) with heavy bulk or delta Mg doping at the junction were grown via molecular beam epitaxy with a hysteresis-free and repeatable negative differential resistance (NDR). The TJ with Mg doping of 5.5 × 1020 cm−3 shows NDR at ∼1.8 V and a large current density of 3.4 KA/cm2 at −1.0 V. Atomic resolution scanning transmission electron microscopy imaging showed no additional defects despite the doping exceeding the solubility limit in GaN allowing subsequent epitaxy of series-connected layers and devices. GaN homojunction TJs grown on bulk GaN showed an improved current density and NDR stability. In addition, the effect of Mg delta doping at the junction was investigated for the first time showing a dramatic improvement in the tunneling characteristics. A metal-organic chemical vapor deposition (MOCVD) grown InGaN light-emitting diode (LED) with an MBE grown GaN homojunction tunnel contact to the MOCVD grown p-GaN layer shows superior lateral conductivity and improved luminescence uniformity, but suffers an added voltage penalty, assumed to be due to interface impurities, compared to control LED with indium-tin-oxide.
Does the Adam-Gibbs relation hold in simulated supercooled liquids?
Authors: Ozawa Misaki , Scalliet Camille , Ninarello Andrea , Berthier Ludovic
Published: August 2019

We perform stringent tests of thermodynamic theories of the glass transition over the experimentally relevant temperature regime for several simulated glass-formers. The swap Monte Carlo algorithm is used to estimate the configurational entropy and static point-to-set lengthscale, and careful extrapolations are used for the relaxation times. We first quantify the relation between configurational entropy and the point-to-set lengthscale in two and three dimensions. We then show that the Adam-Gibbs relation is generally violated in simulated models for the experimentally relevant time window. Collecting experimental data for several supercooled molecular liquids, we show that the same trends are observed experimentally. Deviations from the Adam-Gibbs relation remain compatible with random first order transition theory and may account for the reported discrepancies between Kauzmann and Vogel-Fulcher-Tammann temperatures. Alternatively, they may also indicate that even near Tg thermodynamics is not the only driving force for slow dynamics.
In-situ functionalization of tetrahedral amorphous carbon by filtered cathodic arc deposition
Authors: Sainio Sami , Wester Niklas , Titus Charles J. , Nordlund Dennis , Lee Sang-jun , Koskinen Jari , Laurila Tomi
Published: August 2019

Modification of the surface chemistry of carbon-based nanomaterials is often necessary in order to embrace their full potential. A wide variety of different post-fabrication treatments, such as acid, oxidizing plasma and heat treatments have been described in the literature. However, their specific effects on the materials surface chemistry is typically only vaguely disclosed. Here we report an in-situ method to functionalize tetrahedral amorphous carbon (ta-C) thin films by introducing high purity oxygen into the vacuum chamber during the film fabrication. Additionally, we analyze and compare the material properties of the resulting thin films to those of nitric acid and oxygen plasma treated as well as those with no treatment at all. Using x-ray absorption spectroscopy (XAS), we show that in-situ functionalizing decreases the sp2 content of the surface and increases the amount of carboxyl-like functionalities. Subsequent oxygen plasma treatment further decreases the sp2 fraction and ketone/aldehyde content as well as increases the amount of carboxyl groups. The same trends are observed with the reference ta-C exposed to oxygen plasma treatment. For both materials, a concentrated nitric acid treatment has only a subtle effect on the surface chemistry. Capitalizing on this knowledge, we can selectively produce materials with higher surface loading of specific functional groups, paving the way for application specific material fabrication.
Methods of triggering for the cold-cathode thyratrons with a trigger system based on an auxiliary glow discharge
Authors: Korolev Y. D. , Landl N. V. , Geyman V. G. , Argunov G. A. , Frants O. B. , Bolotov A. V.
Published: August 2019

The paper deals with the investigations of the modernized version of the cold-cathode thyratron TPI1-10k/50 as applied to the problem of nanosecond triggering. The newly developed trigger unit of the device is based on the low-current auxiliary glow discharge with hollow cathode and hollow anode. The regimes for sustaining the auxiliary discharge have been recommended. The characteristic feature of the regimes is that the parasitic current to the main cathode appears due to the ion flow. In such conditions, a rather high hold-off voltage of the device (at a level of 40 kV) is assured. The thyratron with the novel trigger system offers a possibility to use very different methods of triggering. We have proposed and investigated three methods providing the nanosecond stability with respect to the instant at which the trigger pulse arrives to the trigger system. The best results correspond to the case when the jitter in triggering does not exceed of 3 ns.
Planned and unplanned fire regimes on public land in south-east Queensland
Authors: Eliott Martyn , Lewis Tom , Venn Tyron , Srivastava Sanjeev Kumar
Published: August 2019

Land management agencies in Queensland conduct planned burning for a variety of reasons, principally for management of fuels for human asset protection and biodiversity management. Using Queensland Parks and Wildlife Service’s archived manually derived fire reports, this study considered the individual components of the fire regime (extent, frequency and season) to determine variation between planned and unplanned fire regimes in south-east Queensland. Overall, between 2004 and 2015, planned fire accounted for 31.6% and unplanned fire 68.4% of all fire on Queensland Parks and Wildlife Service state-managed land. Unplanned fire was more common in spring (September–October), and planned fire was more common in winter (June–August). Unplanned fire affected 71.4% of open forests and woodlands (148563ha), whereas 58.8% of melaleuca communities (8016ha) and 66.6% of plantations (2442ha) were burnt with planned fire. Mapping fire history at a regional scale can be readily done with existing publicly available datasets, which can be used to inform the assessment of planned burning effectiveness for human asset protection and the management of biodiversity. Fire management will benefit from the continued recording of accurate fire occurrence data, which allows for detailed fire regime mapping and subsequent adaptive management of fire regimes in the public domain.
Leveraging protein dynamics to identify cancer mutational hotspots using 3D structures
Authors: Kumar Sushant , Clarke Declan , Gerstein Mark B.
Published: August 2019

Large-scale exome sequencing of tumors has enabled the identification of cancer drivers using recurrence-based approaches. Some of these methods also employ 3D protein structures to identify mutational hotspots in cancer-associated genes. In determining such mutational clusters in structures, existing approaches overlook protein dynamics, despite its essential role in protein function. We present a framework to identify cancer driver genes using a dynamics-based search of mutational hotspot communities. Mutations are mapped to protein structures, which are partitioned into distinct residue communities. These communities are identified in a framework where residue–residue contact edges are weighted by correlated motions (as inferred by dynamics-based models). We then search for signals of positive selection among these residue communities to identify putative driver genes, while applying our method to the TCGA (The Cancer Genome Atlas) PanCancer Atlas missense mutation catalog. Overall, we predict 1 or more mutational hotspots within the resolved structures of proteins encoded by 434 genes. These genes were enriched among biological processes associated with tumor progression. Additionally, a comparison between our approach and existing cancer hotspot detection methods using structural data suggests that including protein dynamics significantly increases the sensitivity of driver detection.
Neutrophils promote tumor resistance to radiation therapy
Authors: Wisdom Amy J. , Hong Cierra S. , Lin Alexander J. , Xiang Yu , Cooper Daniel E. , Zhang Jin , Xu Eric S. , Kuo Hsuan-Cheng , Mowery Yvonne M. , Carpenter David J. , Kadakia Kushal T. , Himes Jonathon E. , Luo Lixia , Ma Yan , Williams Nerissa , Cardona Diana M. , Haldar Malay , Diao Yarui , Markovina Stephanie , Schwarz Julie K. , Kirsch David G.
Published: August 2019

Nearly two-thirds of cancer patients are treated with radiation therapy (RT), often with the intent to achieve complete and permanent tumor regression (local control). RT is the primary treatment modality used to achieve local control for many malignancies, including locally advanced cervical cancer, head and neck cancer, and lung cancer. The addition of concurrent platinum-based radiosensitizing chemotherapy improves local control and patient survival. Enhanced outcomes with concurrent chemoradiotherapy may result from increased direct killing of tumor cells and effects on nontumor cell populations. Many patients treated with concurrent chemoradiotherapy exhibit a decline in neutrophil count, but the effects of neutrophils on radiation therapy are controversial. To investigate the clinical significance of neutrophils in the response to RT, we examined patient outcomes and circulating neutrophil counts in cervical cancer patients treated with definitive chemoradiation. Although pretreatment neutrophil count did not correlate with outcome, lower absolute neutrophil count after starting concurrent chemoradiotherapy was associated with higher rates of local control, metastasis-free survival, and overall survival. To define the role of neutrophils in tumor response to RT, we used genetic and pharmacological approaches to deplete neutrophils in an autochthonous mouse model of soft tissue sarcoma. Neutrophil depletion prior to image-guided focal irradiation improved tumor response to RT. Our results indicate that neutrophils promote resistance to radiation therapy. The efficacy of chemoradiotherapy may depend on the impact of treatment on peripheral neutrophil count, which has the potential to serve as an inexpensive and widely available biomarker.
Cryo-EM structure of pleconaril-resistant rhinovirus-B5 complexed to the antiviral OBR-5-340 reveals unexpected binding site
Authors: Wald Jiri , Pasin Marion , Richter Martina , Walther Christin , Mathai Neann , Kirchmair Johannes , Makarov Vadim A. , Goessweiner-Mohr Nikolaus , Marlovits Thomas C. , Zanella Irene , Real-Hohn Antonio , Verdaguer Nuria , Blaas Dieter , Schmidtke Michaela
Published: August 2019

Viral inhibitors, such as pleconaril and vapendavir, target conserved regions in the capsids of rhinoviruses (RVs) and enteroviruses (EVs) by binding to a hydrophobic pocket in viral capsid protein 1 (VP1). In resistant RVs and EVs, bulky residues in this pocket prevent their binding. However, recently developed pyrazolopyrimidines inhibit pleconaril-resistant RVs and EVs, and computational modeling has suggested that they also bind to the hydrophobic pocket in VP1. We studied the mechanism of inhibition of pleconaril-resistant RVs using RV-B5 (1 of the 7 naturally pleconaril-resistant rhinoviruses) and OBR-5-340, a bioavailable pyrazolopyrimidine with proven in vivo activity, and determined the 3D-structure of the protein-ligand complex to 3.6 Å with cryoelectron microscopy. Our data indicate that, similar to other capsid binders, OBR-5-340 induces thermostability and inhibits viral adsorption and uncoating. However, we found that OBR-5-340 attaches closer to the entrance of the pocket than most other capsid binders, whose viral complexes have been studied so far, showing only marginal overlaps of the attachment sites. Comparing the experimentally determined 3D structure with the control, RV-B5 incubated with solvent only and determined to 3.2 Å, revealed no gross conformational changes upon OBR-5-340 binding. The pocket of the naturally OBR-5-340-resistant RV-A89 likewise incubated with OBR-5-340 and solved to 2.9 Å was empty. Pyrazolopyrimidines have a rigid molecular scaffold and may thus be less affected by a loss of entropy upon binding. They interact with less-conserved regions than known capsid binders. Overall, pyrazolopyrimidines could be more suitable for the development of new, broadly active inhibitors.
The history of the Atlantic Salmon in Lake Ontario
Authors: Dymond John R. , MacKay Hugh H. , Burridge Mary E. , Holm Erling , Bird Phillip W.
Published: August 2019

The history of the Atlantic Salmon (Salmo salar), also referred to as Salmon below, in Lake Ontario is an accumulation of authentic published accounts, which were almost completed by J. R. Dymond before his death. H. H. MacKay completed the work on Dymond’s behalf (Dymond and MacKay, unpublished, 1966), but it remained largely unknown. The present authors (MEB, EH, PWB) have sought to present an updated subset of Dymond and MacKay’s work as the history of Lake Ontario Salmon is a crucial story in the history of the Great Lakes and its fisheries. The information provided should add materially to the knowledge of the causes that led to the decline and ultimate extirpation of a fascinating and valuable fish, notwithstanding all the efforts that were made to restore it by artificial means.
Accounting for ingrowth of radioactive progeny in dose assessments: generic weighting factors for dose coefficients
Authors: van Dillen Teun , van Dijk Arjan , Kloosterman Astrid , Russo Federica , Mommaert Chantal
Published: August 2019

In this paper, we describe a practical and convenient method to include the contribution of the ingrowth of radioactive progeny in dose assessments of the corresponding parent nuclides. This method modifies the dose coefficients (DCs) of parent nuclides by adding weighted DCs of the corresponding daughter nuclides to them. Based on the decay kinetics of serial nuclear transformations, the progeny weighting factors, with values between 0 and 1, are derived by analysis of the time-integrated activity of each nuclide in the (branched) decay chain headed by a parent nuclide. Using the electronic, nuclear-decay database of Publication 107 of the International Commission on Radiological Protection (ICRP 2008), DC weighting factors for annual dose assessments are calculated for all daughter radionuclides in the decay chains and are tabulated in this paper. Weighting factors based on integration periods other than one year, ranging from 1 h–70 years, are also provided (see the supplementary material). With a priori established weighting factors, dose assessments become significantly simplified by considering the decay kinetics of only the parent nuclides and by applying the modified DCs. This ensures that the ingrowth of progeny is taken into account realistically. In some cases, one requires a conservative estimate of the dose, for instance when dealing with issues of the clearance of materials under regulatory control. Therefore, we adapted the weighting-factor method to derive conservative DC weighting factors for dose evaluations. These values are calculated for various integration periods and compared with those from an existing method adopted by the Euratom Article 31 Group of Experts and by the International Atomic Energy Agency. Identical progeny weighting factors are obtained for long-lived parent radionuclides, whereas for short-lived parent radionuclides, the new method can yield significantly larger values. For example, the weighting factor of I-131 (daughter of parent Te-131) increases from 0.002 to 1.0 based on an integration period of 1 year. The progeny DC weighting factors, derived based on nuclear transformations in exit-only decay chains, may not always be suitable for use in radiological dose evaluations. For instance, when environmental removal pathways are dominant, the application of these weighting factors may have its limitations. This paper, therefore, provides guidance on the proper selection and application of weighting factors.
Satire
Authors: Stinson Emmett
Published: August 2019

Although scholars generally agree that satire cannot be defined in a categorical or exhaustive way, there is a consensus regarding its major features: satire is a mode, rather than a genre; it attacks historically specific targets, who are real; it is an intentional and purposeful literary form; its targets deserve ridicule on the basis of their behavior; and satire is both humorous and critical by its nature. The specificity and negativity of satire are what separates it from comedy, which tends to ridicule general types of people in ways that are ultimately redemptive. Satire is also rhetorically complex, and its critiques have a convoluted or indirect relation to the views of the author. Satire’s long history, which is not straightforwardly linear, means that it is impossible to catalogue all of the views on it from antiquity through to modernity. Modern criticism on satire, however, is easier to summarize and has often made use of ancient satirical traditions for its own purposes—especially because many early modern theorists of satire were also satirists. In particular, modern satire has generated an internal dichotomy between a rhetorical tradition of satire associated with Juvenal, and an ethical tradition associated with Horace. Most criticism of satire from the 20th century onward repeats and re-inscribes this binary in various ways. The Yale school of critics applied key insights from the New Critics to offer a rhetorical approach to satire. The Chicago school focused on the historical nature of satirical references but still presented a broadly formalist account of satire. Early 21st century criticism has moved between a rhetorical approach inflected by poststructural theory and a historicism grounded in archival research, empiricism, and period studies. Both of these approaches, however, have continued to internally reproduce a division between satire’s aesthetic qualities and its ethical or instrumental qualities. Finally, there is also a tradition of Menippean satire that differs markedly in character from traditional satire studies. While criticism of Menippean satire tends to foreground the aesthetic potential of satire over and above ethics, it also often focuses on many works that are arguably not really satirical in nature.
The Vietnam War and Asian American Literature
Authors: Park Josephine Nock-Hee
Published: August 2019

The first wave of the now-canonical literature of the Vietnam War featured the GI grunt, the wary officer, and the rock-and-roll journalist—all embattled and disillusioned white men. These fictions, memoirs, and reportage came to define the expressive labor shaped by the ethical morass of the war, and these differing genres melded in the cinematic renaissance occasioned by the Vietnam War, which installed a generation of American auteurs. Asian American writers contended with this potent cultural formation, not only to critique the popular imagination of white innocence lost, but to claim the force and even intoxication of this cultural juggernaut. Asian American literary texts from the 1970s onward were shaped by the war and its aftermath—notably including the resistance movements it sparked—and the 21st-century rise of Vietnamese American reckonings with the war’s legacy has instigated significant reappraisals of the aims and effects of the war.

The foundational Asian American literary writings of Maxine Hong Kingston and Frank Chin weighed the service of the Asian American soldier in Vietnam in the context of the Third World movements that drove the formation of Asian American studies. A decade later, the publication of bestselling memoirs by Le Ly Hayslip, popularly heralded as the emergence of a Vietnamese American voice, marked the origins of a burgeoning field of writing, wide-ranging in form and genre but arrayed alongside and against the mainstream imagination of Vietnam. The major fiction of Viet Thanh Nguyen’s The Sympathizer (2015) has come to stand as a culminating literary riposte to the canonized first wave of Vietnam War literature: Nguyen’s Pulitzer Prize-winning novel exposes long-standing fictions of U.S. conduct and foregrounds a complex Asian American and refugee perspective. Asian American literature of the Vietnam War expresses a dynamic range of felt responses to the cultural history of the war to produce imaginative work that interrogates the war’s iconic images and reveals its unseen subjects.
Asians and Asian Americans in Early Science Fiction
Authors: Cheng John
Published: August 2019

This essay considers the expressive and figurative dynamics of Asians in science fiction in the early 20th century. Racial sentiment and policy in the era saw and defined Asians as “ineligible aliens” to exclude from immigration and citizenship. Asian figures expressed these dynamics in science fiction, adapting Orientalist tropes and Yellow Peril themes to the imperatives of the emergent genre. The invisible menace of villainous masterminds like Fu Manchu from crime and detective fiction were refigured as visible science fiction foes whose defeat redeemed the power and potential of science from its degenerate and dehumanizing application. Asian racial tropes aligned particularly with science fiction’s concern about extra-terrestrial life forms. While the term “alien” was not used in the period for such creatures, its later prominence expressed valences and associations, particularly with “invasion,” that Asians originally represented in the genre.
Space in Rhetorical Theory
Authors: McAlister J. Faber
Published: August 2019

The phrase “space in rhetorical theory” refers to scholarship that explores the relationships between place and persuasion, location and identity, and/or spatial dimensions of communication and communicative functions of spaces. These relationships have been theorized in a wide variety of ways, from classical conceptions of topos and the agora to recent work on new materialist and mobile rhetorics. Key themes in this research have included (1) settings where rhetoric takes place, (2) spatial metaphors for theorizing rhetoric, (3) rhetorical representations of public places, (4) the role of place in identity, (5) spatial aspects of rhetoric, (6) rhetorical functions of space, and (7) spatial-temporal-material relations.

Rhetorical scholarship on such topics has been shaped by metadisciplinary movements, such as the visual, spatial, and affective “turns” in the humanities and social sciences. Rhetoricians of space have drawn on and contributed to widespread interest in public memory, mobile technologies, national borders, environmental communication, and global flows of capital and labor and tourism. Researchers in this arena of rhetorical studies have also addressed problems taken up by critical/cultural theorists more recently, including collective agency, posthuman subjectivity, and animate matter—each of which poses challenges to conventional distinctions between subjects (as individual human rational actors) and objects (as lifeless things to be acted upon). Reconsidering these categories is important when conceptualizing place-making processes and the forces exerted by living landscapes. In pursuing these topics and questions, rhetorical theorists have contributed to conversations among researchers in multiple areas of specialty within communication studies. Such research also engaged themes of interest to scholars of cultural geography, urban planning, gender and sexuality studies, literary criticism, environmental science, and additional diverse disciplines as well as interdisciplinary movements.

Communication scholars studying precarity, mobility, and other evolving topics are generating promising new contributions to conversations on space and rhetoric each year. However, essential insights regarding space and rhetorical theory are still being mined from postcolonial/decolonial, critical race, feminist, and queer approaches that many critics argue are insufficiently incorporated into the rhetorical theories of space or spatial theories of rhetoric most often applied and taught.
Public Relations and Journalism
Authors: Sherwood Merryn , Marjoribanks Timothy , Nicholson Matthew
Published: August 2019

The relationship between journalism and public relations in the 21st century has been mostly marked by tension, at least publicly. Many journalists’ accounts of public relations portray it as “the dark side” and characterize public relations practitioners as purveyors of “spin.” However, extensive research examining the input of public relations practitioners into the news has found that the products of their work—such as media releases or media conferences—are crucial in facilitating the news cycle. As one of the classic studies of news production identified, “News is, after all, not what journalists think, but what their sources say.” Decades of research have established that news sources are often likely to be public relations practitioners, with anywhere between 40% and 75% of news originating from public relations practitioners or the products of their work. Public relations is, therefore, critical to the work of journalism; however, journalists often deny this as part of publicly upholding the standards of their profession and building and maintaining boundaries of control over their work.

However, the symbiotic relationship that formed the basis of news production in the 20th century is being upended in the 21st century as organizations become their own media producers. This means the lines continue to blur between journalism and public relations, both for individuals working across once clear occupational and professional boundary lines and for organizations adopting the functions of both.
HIV/AIDS Politics and Policy in Eastern Europe and Central Asia
Authors: Pape Ulla
Published: August 2019

Eastern Europe and Central Asia (EECA) is the only region in the world where annual HIV infection rates continue to grow. According to the Joint United Nations Program on HIV/AIDS (UNAIDS), in 2019 approximately 1.4 million people in the region were living with HIV. The main factors that have contributed to the spread of the epidemic over the past two decades include injecting drug use, the stigmatization and marginalization of vulnerable groups, the increasing spread of HIV into the general population, and the lack of evidence-based prevention and treatment programs necessary for controlling the epidemic. Limited access to life-saving antiretroviral treatment has intensified the impact of the epidemic in EECA and increased mortality rates among people living with HIV (PLWH).

In the post-Soviet space, Russia is experiencing by far the biggest HIV/AIDS epidemic. This can be attributed largely to the government’s failure to introduce evidence-based prevention measures for vulnerable groups, e.g., harm reduction programs, which are recommended by international health organizations. Other countries in the region have been more pragmatic in their approach and introduced harm reductions programs on a broader scale. In Ukraine, the efforts to combat HIV, which led to an initial stabilization of the epidemic in 2012, have been endangered by the military conflict in the eastern part of the country and subsequent internal displacement, which has increased HIV vulnerability. In comparison with Russia and Ukraine, the countries of the South Caucasus and Central Asia are less affected by HIV. However, labor migration to Russia constitutes a persistent risk factor for HIV transmission from higher-prevalence Russia to lower-prevalence South Caucasus and Central Asia.

Although initially the HIV/AIDS epidemic has been mainly driven by injecting drug use, it is also clearly linked to lesbian, gay, bisexual, and transgender (LGBT) politics and policies in EECA. Because of widespread stigmatization and marginalization, the spread of HIV within LGBT communities remains underreported and is barely visible in official HIV statistics. This makes it difficult for prevention programs to reach out to vulnerable groups. In all countries in the region, prevention efforts among LGBT communities remain inadequate and largely depend on local civil society organizations (CSOs), which lack the capacities to provide nationwide information campaigns and other prevention programs for the LGBT community. In addition, the work of CSOs that advocate for HIV prevention among LGBT groups is further undermined by repressive laws, e.g., the 2013 “gay propaganda law” in Russia, which has increased the stigmatization of LGBT people and has made prevention outreach more difficult. Research has contributed to our understanding of HIV vulnerability and its impact in EECA. Further research is needed, however, into the social and political factors that explain the persistent failure of regional decisionmakers to adequately address the growing HIV epidemic.
The Politics of Pentecostalism in Africa
Authors: McCauley John F.
Published: August 2019

Charismatic Pentecostalism constitutes perhaps the most important contemporary movement in sub-Saharan Africa, combining extremely rapid growth with an informal political presence. The movement has expanded in Africa by bringing traditional spirituality into a modern setting, offering social and economic hope to both the upwardly mobile and the destitute. Despite having minority status, its messages of pending prosperity and spiritual warfare, and its astute exploitation of mass media, have positioned the Charismatic Pentecostal movement to exert important if informal influence on politics in the region. It is reshaping the channels through which resources flow from Big Men to their followers; it is implicating new and different international actors; and it is allowing followers to live fully within the church through the provision of social services. Perhaps most importantly, the movement has introduced language of national identity—of good and evil, and Christian nations—that captivates just as it divides. Its potential to influence the formal politics of institutions and parties is limited by the absence of organizational hierarchy and a central focus on remaking the individual rather than addressing social injustices. Nevertheless, by informal means, the movement has “Pentecostalized” politics in many African countries.
Iran and European Union Politics
Authors: Harnisch Sebastian
Published: August 2019

The Islamic Republic of Iran and the European Union (EU) have not yet established formal diplomatic relations, but since 1979 the Union and its member states have had various strong if often conflictual interactions. The relationship has been marked by distinct phases that reflect the emerging character of the partners, a theocratic republic on the one hand and a Union of interdependent democratic states on the other. While mutual economic interests have formed the basis for substantial interactions, relations with member states and the EU itself have been colored by a long and sometimes hurtful history of European states’ role in Iranian politics, including the Russian and British imperial influence over Persia in the late 19th and early 20th century, the British (and American) involvement in the coup against democratically elected Prime Minister Mohammad Mosaddeq in 1953, and the French hosting of Ayatollah Ruhollah Khomeini, an avowed critic of the Pahlavi dynasty, prior to the anti-authoritarian revolution in 1979. Over time, the relationship has substantially shaped the character and direction of the politics of the EU’s common foreign and security policy, resulting in more policy coherence between member states and the EU, more policy autonomy, particularly vis-á-vis the United States, and more proactive behavior, such as during the nuclear negotiations leading to the Joint Comprehensive Plan of Action (in 2015). By engaging with a problematic member of the nonproliferation treaty, the EU not only specified and thus strengthened the treaty, but it also grew into an international nonproliferation actor to reckon with.
Trade Union Politics in Latin America
Authors: Bensusán Graciela
Published: August 2019

The links between unions and political parties have been present throughout much of the 20th century and early 21st century in most Latin American countries. Since these links were historically one of the most important resources of union power, by compensating the structural weakness of wage-workers in the labor market, their weakening in the framework of economic transformations and ideological turns generates a greater concern on the future of trade unions. In this context, there has been an increased urgency to reconsider old political identities and construct other resources for power, such as alliances with social movements and international solidarity.

The new bonds forged under democratic regimes or during the transition processes were more flexible, informal and with greater autonomy between partnerships than the old ones that resulted from the initial incorporation of workers in the political arena under authoritarian regimes. Consequently, in those cases greater opportunities can be opened to democratize and revitalize unions through the construction of new sources of power.
State Formation and Conflict in Africa
Authors: Péclard Didier
Published: August 2019

Dominant narratives and theories developed at the turn of the 21st century to account for the links between state formation and civil wars in Africa converged around two main ideas. First was the contention that the increase in civil wars across the continent—like that in many parts of the globe, including South Asia and Central Europe—was linked to state failure or decay. Violent conflict thus came to be seen as the expression of the weakness, disintegration, and collapse of political institutions in the postcolonial world. Second, guerrilla movements, once viewed as the ideological armed wings of Cold War contenders, then came to be seen as roving bandits interested in plundering the spoils left by decaying states, and their motives as primarily, if not only, economic or personal, rather than political. However, recent research has challenged the reductionism that underlay such accounts by looking into the day-to-day politics of civil war, thus moving beyond the search for the motives that bring rebels and rebel movements to wage war against the established order. Drawing on this literature, this article argues that violent conflict is part and parcel of historical processes of state formation. Thus, in order to understand how stable political institutions can be built in the aftermath of civil war, it is essential to study the institutions that regulate political life during conflict. This implies a need not only to look at how (and if) state institutions survive once war has broken out, but also to take into account the institutions put in place in areas beyond the control of the state.