bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficiency calculation of a thermoelectric generator for investigating the applicability of various thermoelectric materials
Authors: Gaurav Kumar , Pandey Sudhir K.
Published: February 2017

Accurate measurement of efficiency for a thermoelectric generator (TEG) is of great importance for materials research and development. Approximately all the parameters of a thermoelectric material (TEM) are temperature dependent, and so we cannot directly apply the ηmax formula for efficiency calculation in the large temperature range. In this work, we have calculated TEG efficiency, and we study the suitability of different TEMs like Bi2Te3, Sb2Te3, PbTe, TAGS ((AgSbTe2)0.15(GeTe)0.85), CeFe4Sb12, SiGe, and TiO1.1 in the estimation of TEG efficiency. The efficiency of TEG made up of Bi2Te3 or Sb2Te3 gives ∼7% in the temperature range of 310 K–500 K. PbTe or TAGS or CeFe4Sb12 generates ∼6% in the temperature range of 500 K–900 K and SiGe or TiO1.1 also have remarkable efficiency in the higher temperature range, i.e., ∼1200 K. The calculated efficiency obtained is close to experimental results. Here, we report the enhancement of efficiency by using the segmented technique for different combinations of the above-mentioned materials. To this end, the proposed values of overall efficiency of TEG by segmenting Bi2Te3 and PbTe; Bi2Te3 and TAGS; Bi2Te3 and CeFe4Sb12 are 12%, 14%, and 11.88%, respectively, for the temperature range of 310 K–900 K. For automobiles, the efficiency of TEG having fixed exhaust temperature with varying sink temperature is also discussed. For the steel industry and spacecraft applications (up to 1200 K), either segmentation is done by comprising Bi2Te3, PbTe and SiGe, or Bi2Te3 and TiO1.1, which yields an efficiency of ∼15.2% and ∼17.2%, respectively. The relative change in efficiency by considering loss at the interface surface is found to be 10.5%. The proposed methodology and results can be treated as a viable option for engineers who are looking to fabricate TEG in real life by using the temperature dependent material's parameters such as thermal conductivity, electrical conductivity, and Seebeck coefficient on which zT¯ depends.
Temperature dependent FCS studies using a long working distance objective: Viscosities of supercooled liquids and particle size
Authors: Połatyńska Agnieszka , Tomczyk Karolina , Pochylski Mikołaj , Meier Gerd , Gapinski Jacek , Banachowicz Ewa , Śliwa Tomasz , Patkowski Adam
Published: February 2017

In this work, we describe new experimental setups for Fluorescence Correlation Spectroscopy (FCS) where a long working distance objective is used. Using these setups, FCS measurements in a broad temperature range for a small sample volume of about 50 μl can be performed. The use of specially designed cells and a dry long working distance objective was essential for avoiding temperature gradients in the sample. The performance of the new setups and a traditional FCS setup with immersion objectives is compared. The FCS data in combination with the Stokes-Einstein (SE) relation were used to obtain the values of the nanoviscosity of a fluid. We show for selected molecular van der Waals supercooled liquids that despite the fact that in these systems, a characteristic length scale can be defined, the nanoviscosity obtained from FCS is in a very good agreement with the macroscopic (rheometric) viscosity of the sample in a broad temperature range. This result corroborates the applicability of the SE relation to supercooled liquids at temperatures above 1.2 Tg. We also show that the temperature dependent size of thermoresponsive microgel particles can be determined by FCS using the designed cells and a long working distance objective in a broader size range without a need to use the correction procedure since the size correction is proportional to the square of the ratio of the hydrodynamic radius to the confocal volume size.
Quantum conductance in MoS2 quantum dots-based nonvolatile resistive memory device
Authors: Wang Dongliang , Ji Fengzhen , Chen Xinman , Li Yan , Ding Baofu , Zhang Yong
Published: February 2017

In this work, nonvolatile bipolar resistive switching behaviors based on the MoS2 quantum dots (QDs) embedded in the insulating polymethylmethacrylate (PMMA) were reported with the device configuration of Au/PMMA/PMMA:MoS2 QDs/PMMA/fluorine doped tin-oxide. The device exhibits the reversible switching performances with the excellent read endurance and data retention capability. The related carrier transport behaviors were predominated by Schottky emission and Ohmic conductions in OFF and ON states, respectively. Importantly, a conductance quantization effect was evidently observed in this MoS2 QD-based memory device. Combined with the energy band evolution, these phenomena were elucidated in views of electrons trapping/de-trapping and quantum tunneling effects of nanoscale MoS2 QDs. This work also suggests the potential application of MoS2 QDs in next generation ultra-high-density data storage.
Optically induced lattice deformations, electronic structure changes, and enhanced superconductivity in YBa2Cu3O6.48
Authors: Mankowsky R. , Fechner M. , Först M. , von Hoegen A. , Porras J. , Loew T. , Dakovski G. L. , Seaberg M. , Möller S. , Coslovich G. , Keimer B. , Dhesi S. S. , Cavalleri A.
Published: February 2017

Resonant optical excitation of apical oxygen vibrational modes in the normal state of underdoped YBa2Cu3O6+x induces a transient state with optical properties similar to those of the equilibrium superconducting state. Amongst these, a divergent imaginary conductivity and a plasma edge are transiently observed in the photo-stimulated state. Femtosecond hard x-ray diffraction experiments have been used in the past to identify the transient crystal structure in this non-equilibrium state. Here, we start from these crystallographic features and theoretically predict the corresponding electronic rearrangements that accompany these structural deformations. Using density functional theory, we predict enhanced hole-doping of the CuO2 planes. The empty chain Cu dy2-z2 orbital is calculated to strongly reduce in energy, which would increase c-axis transport and potentially enhance the interlayer Josephson coupling as observed in the THz-frequency response. From these results, we calculate changes in the soft x-ray absorption spectra at the Cu L-edge. Femtosecond x-ray pulses from a free electron laser are used to probe changes in absorption at two photon energies along this spectrum and provide data consistent with these predictions.
Probing electron beam effects with chemoresistive nanosensors during in situ environmental transmission electron microscopy
Authors: Steinhauer S. , Wang Z. , Zhou Z. , Krainer J. , Köck A. , Nordlund K. , Djurabekova F. , Grammatikopoulos P. , Sowwan M.
Published: February 2017

We report in situ and ex situ fabrication approaches to construct p-type (CuO) and n-type (SnO2) metal oxide nanowire devices for operation inside an environmental transmission electron microscope (TEM). By taking advantage of their chemoresistive properties, the nanowire devices were employed as sensitive probes for detecting reactive species induced by the interactions of high-energy electrons with surrounding gas molecules, in particular, for the case of O2 gas pressures up to 20 mbar. In order to rationalize our experimental findings, a computational model based on the particle-in-cell method was implemented to calculate the spatial distributions of scattered electrons and ionized oxygen species in the environmental TEM. Our approach enables the a priori identification and qualitative measurement of undesirable beam effects, paving the way for future developments related to their mitigation.
Effect of dietary sodium diacetate on growth performance, carcass characteristics, meat quality, intestinal pH and Escherichia coli of broilers
Authors: Wen Aiyou , Bai Xi , Dai Sifa , Shah Assar Ali , Hu Hong
Published: February 2017

This research report investigated the influences of diet supplemented with sodium diacetate (SD) on growth performance, carcass characteristics, meat quality, and intestinal pH and Escherichia coli count of broilers. A total of 240 1-day-old Arbor Acres chicks were randomly allocated into four groups fed with basal diets containing 0% (Control group), 0.01%, 0.03%, and 0.05% SD. At 42 days of age, the final weight, bodyweight gain, pre-evisceration weight, eviscerated weight, and breast muscle weight were increased in the 0.05% SD group compared with the Control group (P < 0.05). The 0.05% SD group also showed an increased water-holding capacity in the breast and thigh meat (P < 0.05). However, this group also showed a decrease in the lightness value of thigh meat (P < 0.05). There was a tendency towards a decrease in pH values of duodenum, jejunum, ileum, and appendix with the increase in SD supplementation (0.01–0.05%). Broilers in the 0.05% SD group had a lower pH in the jejunum than those in the Control group (P < 0.05). SD supplementation in diets decreased the E. coli count in the small and large intestines (P < 0.05). This study suggests that SD supplementation in diets provides a nutritional strategy to improve growth performance, carcass characteristics, meat quality, and intestinal health of broilers.
Oligomeric lipoprotein PelC guides Pel polysaccharide export across the outer membrane of
Pseudomonas aeruginosa
Authors: Marmont Lindsey S. , Rich Jacquelyn D. , Whitney John C. , Whitfield Gregory B. , Almblad Henrik , Robinson Howard , Parsek Matthew R. , Harrison Joe J. , Howell P. Lynne
Published: February 2017

Significance

Pseudomonas aeruginosa
biofilms are exceedingly difficult to eradicate once established. This resilience is facilitated, in part, by the secretion of polysaccharides that contribute to biofilm structural integrity. The cationic exopolysaccharide PEL plays an important role in disease pathogenesis; however, the mechanisms underlying its biosynthesis are poorly understood. In this work, we identify the
pel
operon in more than 125 proteobacteria, demonstrating that its distribution was previously underestimated. We show that the essential outer membrane-anchored protein PelC forms a 12-subunit ring with an electronegative surface that we propose guides PEL toward the membrane-embedded secretion channel. Our work provides insight into a widespread outer membrane infrastructure unobserved in any other currently identified polysaccharide biosynthetic apparatus.
Microbial community assembly and evolution in subseafloor sediment
Authors: Starnawski Piotr , Bataillon Thomas , Ettema Thijs J. G. , Jochum Lara M. , Schreiber Lars , Chen Xihan , Lever Mark A. , Polz Martin F. , Jørgensen Bo B. , Schramm Andreas , Kjeldsen Kasper U.
Published: February 2017

Significance

Our study shows that deep subseafloor sediments are populated by descendants of rare members of surface sediment microbial communities that become predominant during burial over thousands of years. We provide estimates of mutation rates and strength of purifying selection in a set of taxonomically diverse microbial populations in marine sediments and show that their genetic diversification is minimal during burial. Our data suggest that the ability of subseafloor microbes to subsist in the energy-deprived deep biosphere is not acquired during burial but that these microbes were already capable of living in this unique environment. These findings represent a significant step toward understanding the bounds for life in the deep biosphere and its connection to life in the surface world.
Quantification of labile heme in live malaria parasites using a genetically encoded biosensor
Authors: Abshire James R. , Rowlands Christopher J. , Ganesan Suresh M. , So Peter T. C. , Niles Jacquin C.
Published: February 2017

Significance

Malaria parasites degrade substantial quantities of hemoglobin to release heme within a specialized digestive vacuole. Most of this heme is sequestered in an inert crystal. However, the concentration of bioavailable, labile heme in the parasite’s cytosol was unknown. We developed a biosensor to provide the first quantitative insights into labile heme concentrations in malaria parasites. We find that ∼1.6 µM labile cytosolic heme is maintained, including during a period coincident with intense hemoglobin degradation. The heme-binding antimalarial drug, chloroquine, which interferes with heme crystallization, specifically induces an increase in labile heme. The ability to quantify labile heme in malaria parasites opens opportunities for better understanding heme homeostasis, signaling, and metabolism, and its association with antimalarial potency.
Human-started wildfires expand the fire niche across the United States
Authors: Balch Jennifer K. , Bradley Bethany A. , Abatzoglou John T. , Nagy R. Chelsea , Fusco Emily J. , Mahood Adam L.
Published: February 2017

Significance

Fighting wildfires in the United States costs billions of dollars annually. Public dialog and ongoing research have focused on increasing wildfire risk because of climate warming, overlooking the direct role that people play in igniting wildfires and increasing fire activity. Our analysis of two decades of government agency wildfire records highlights the fundamental role of human ignitions. Human-started wildfires accounted for 84% of all wildfires, tripled the length of the fire season, dominated an area seven times greater than that affected by lightning fires, and were responsible for nearly half of all area burned. National and regional policy efforts to mitigate wildfire-related hazards would benefit from focusing on reducing the human expansion of the fire niche.
Structural basis of autoregulatory scaffolding by apoptosis signal-regulating kinase 1
Authors: Weijman Johannes F. , Kumar Abhishek , Jamieson Sam A. , King Chontelle M. , Caradoc-Davies Tom T. , Ledgerwood Elizabeth C. , Murphy James M. , Mace Peter D.
Published: February 2017

Significance

Phosphorylation catalyzed by protein kinases governs many aspects of cellular behavior. Apoptosis signal-regulating kinases (ASK1–3) trigger responses to stress, but the structural basis of their regulation remains unclear. Here, we show that a domain directly adjacent to the ASK1 kinase domain promotes activity of ASK1 on a key substrate and also orients an additional ASK1 domain nearby to suppress kinase activity. The structure of this regulatory domain appears to be shared by all ASK kinases and provides a versatile mechanism to control ASK activity in response to various stress stimuli.
TorsinA controls TAN line assembly and the retrograde flow of dorsal perinuclear actin cables during rearward nuclear movement
Authors: Saunders Cosmo A. , Harris Nathan J. , Willey Patrick T. , Woolums Brian M. , Wang Yuexia , McQuown Alex J. , Schoenhofen Amy , Worman Howard J. , Dauer William T. , Gundersen Gregg G. , Luxton G.W. Gant
Published: February 2017

The nucleus is positioned toward the rear of most migratory cells. In fibroblasts and myoblasts polarizing for migration, retrograde actin flow moves the nucleus rearward, resulting in the orientation of the centrosome in the direction of migration. In this study, we report that the nuclear envelope–localized AAA+ (ATPase associated with various cellular activities) torsinA (TA) and its activator, the inner nuclear membrane protein lamina-associated polypeptide 1 (LAP1), are required for rearward nuclear movement during centrosome orientation in migrating fibroblasts. Both TA and LAP1 contributed to the assembly of transmembrane actin-associated nuclear (TAN) lines, which couple the nucleus to dorsal perinuclear actin cables undergoing retrograde flow. In addition, TA localized to TAN lines and was necessary for the proper mobility of EGFP-mini–nesprin-2G, a functional TAN line reporter construct, within the nuclear envelope. Furthermore, TA and LAP1 were indispensable for the retrograde flow of dorsal perinuclear actin cables, supporting the recently proposed function for the nucleus in spatially organizing actin flow and cytoplasmic polarity. Collectively, these results identify TA as a key regulator of actin-dependent rearward nuclear movement during centrosome orientation.
TorsinA regulates the LINC to moving nuclei
Authors: Starr Daniel A. , Rose Lesilee S.
Published: February 2017

How LINC complexes are regulated to connect nuclei to the cytoskeleton during nuclear migration is unknown. Saunders et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201507113) show that the AAA+ ATPase torsinA and its partner LAP1 are required for nuclear migration during fibroblast polarization by mediating the dynamics of LINC complexes.
Indigeneity and Early American Literature
Authors: Newman Andrew
Published: February 2017

Indigeneity is the abstract noun form of “indigenous,” defined by the Oxford English Dictionary as “Born or produced naturally in a land or region”; in conventional usage, it refers primarily to “aboriginal inhabitants or natural products.” Indigeneity has a conceptually complex relationship to American literary history before 1830, insofar as, for most of the history of the field, “early American literature” has predominately referred to works written in European languages, scripts, and genres, produced by peoples of European origin and their descendants. Within this framework, until Native Americans began adopting and adapting these languages, scripts, and genres for their own use, there were no literary works that might be simultaneously characterized as “indigenous” and “early American.”

Four conceptualizations of the relationship between indigeneity and early American literature provide a basis for this history and its historiography. Three of these pertain to cultural works produced at least in part by Native Americans: these are (1) written representations of Native American spoken performances, or “oral literature”; (2) writings that register various degrees of participation in literacy practices by Native American converts to Christianity; and (3) cultural works that employ non-alphabetic indigenous sign-systems, or “indigenous literacies.” These formulations variously challenge conventional ideas about literature and related terms such as authorship and writing; in the case of the Christian Indians, they can also challenge notions of indigeneity.

A fourth conceptualization of the relationship between indigeneity and early American literature is premised on narrow definitions of these seemingly antithetical terms: it pertains to the aesthetic project of some settler-colonial authors who hoped to connect their prose and verse works to the domestic landscape, to assert their cultural independence from England, and to enact the replacement of Native American cultural traditions with their own.
Representations of Native Americans in the Mass Media
Authors: Kelly Casey Ryan
Published: February 2017

The historical construction of Indian in American popular culture poses serious challenges for conducting research about representations of indigenous culture, identity, and politics. Mass-mediated representation deserves specific attention, as popular entertainment has been one of the most significant historic battlegrounds over the status of indigenous identity in American culture. Representations of American Indians have been reworked and negotiated as they have circulated through a variety of mediums, including theatrical performances, silent films, Westerns, prime time television, independent films, advertising, sports culture, and so on.

Beginning with Buffalo Bill’s Wild West show and Thomas Edison’s kinetoscope, introduced the at the 1893 Chicago Columbian World’s Exposition, American mass entertainment has been preoccupied with the drama of westward expansion and the noble savage of the American frontier. Later, the films of John Ford developed the Hollywood image of the screen savage. Film continued to address the topic of American Indians through the lens of the 1960’s and 1970’s counterculture, 1980’s imperial nostalgia, 1990s sympathy and revisionism, and, in the 21st century, through native filmmaker’s reclamation of indigenous visual sovereignty. Not all media are uniform in their portrayals. The televisual Indian evolved quite differently than her/his counterpart in film. At some points, television has been even more progressive in its portrayals of American Indian characters, more willing to feature native actors and storylines than mainstream Hollywood film. Besides film and television, sports and advertising have had the most influence on popular conceptions of American Indians. While commodified images of American Indians are ubiquitous in popular culture, sport culture (mascots) has become the most popular site where Indian imagery is used to generate a profit. Struggles over everything from the moving image to sports mascots demonstrate the importance of studying the power of the image, particularly in the context of American settler colonialism.
Interpersonal Communication Across the Life Span
Authors: Fisher Carla L. , Roccotagliata Thomas
Published: February 2017

From birth to death, our interactions with others are what inform our identity and give meaning to life. Ultimately, it is interpersonal communication that is the bedrock of wellness. Much of the scholarship on interpersonal communication places communication in the background, characterized merely as a resource, symptom, or contributing factor to change. In the study of our interpersonal experiences, communication must be at the forefront. As a pragmatic lens concerned with real-world issues, a life-span perspective of interpersonal scholarship provides boundless opportunities for bridging science and practice in meaningful ways that improve social life on multiple levels, from families to schools to government to hospitals. Interpersonal communication research that is concerned with life-span issues tends to prioritize communicative phenomena and bring the communication dynamics of our relational lives to the surface. Typically, this scholarship is organized around the various stages or phases of life. In other words, researchers concerned with interpersonal communication often contextualize this behavior based on dimensions of human development and life changes we typically encounter across the life course, those major life experiences from birth to death. Much of that scholarship also centers on how we develop competence in communication across time or how communication competence is critical to our ability to attain relational satisfaction as well as a high psychological and physical quality of life. This research also highlights the influential role of age, human development, and generational differences, recognizing that our place in the life span impacts our goals and needs and that our sociocultural-historical experiences also inform our communication preferences. A life-span perspective of interpersonal communication also encompasses various theoretical paradigms that have been developed within and outside the communication discipline. Collectively, this scholarship helps illustrate the communicative nature of human life across the entire life trajectory.
The Foxfire of Fair Use: The Google Books Litigation and the Future of Copyright Laws
Authors: Rimmer Matthew
Published: February 2017

Copyright exceptions and limitations in the United States have experienced dynamic evolution in light of new technological developments. There has been significant legal debate in the courts and in the United States Congress about the scope of the defense of fair use. The copyright litigation over Google Books has been a landmark development in the modern history of copyright law. The victory by Google, Inc., over the Authors Guild in the decade-long copyright dispute is an important milestone for copyright law. The ruling of Leval J emphasizes that the defense of fair use in the United States plays a critical role in promoting transformative creativity, freedom of speech, and innovation. The Supreme Court of the United States was decisive in its rejection of the Authors Guild’s efforts to challenge the decision of Leval J. There has been significant debate in the United States Copyright Office and United States Congress over the development of “the Next Great Copyright Act.” Hearings have taken place within the United States Congressional system about the history, nature, and future of the defense of fair use under United States copyright law. There remains much debate about the internationalization of the defense of fair use, and the need for the trading partners of the United States to enjoy similar flexibilities with respect to copyright exceptions. There has been concern about the impact of mega-regional trade agreements—such as the Trans-Pacific Partnership—upon copyright exceptions, such as the defense of fair use.
Death and Dying: An Intergroup Communication Approach
Authors: Chen Chien-Yu
Published: February 2017

Death is inevitable: We witness the death of others and eventually face our own. However, people in general view death as taboo and tend to avoid discussing their own or others’ mortality. A cultural shift has been taking place in the developed world so that dying has become an increasingly medicalized process, where death is viewed as something to be stopped or delayed instead of accepted as part of a natural life cycle. As family members are less responsible for the dying process, communication about death and dying becomes a sensitive topic and is often ignored or avoided. Lack of this meaningful communication can lead to stereotypes about the dying person, conflict among family members, and fear of death. Talking about death and dying, if done correctly, can have a positive impact on health-care delivery and the bereavement process.

Incorporating knowledge of intergroup communication with a lifespan approach can deepen communication effectiveness about death and dying. People’s group identities can play important roles in the conversation about death and dying. As children and adolescents, people can encounter the death of older family members (e.g., grandparents) and the communication here can be intergenerational. Due to age differences, younger adults may feel uncomfortable to react to older adults’ painful disclosure of death and the bereavement process. During adulthood, people deal with the death uncertainty for themselves and their loved ones. The communication in this period can be intergenerational and inter-occupational, especially when there are third parties involved (e.g., medical providers or legal authorities). Death and dying communication tend to happen mostly, albeit not always, during the later lifespan, as time of death approaches, among older adults, family members, and medical providers. These conversations include advanced care planning (i.e., arrangements and plans about the dying process and after death), medical decision making, palliative care, and final talks. Increasing the awareness of death and dying can help to normalize the dying process.
Organized Crime in Foreign Policy
Authors: Swanström Niklas , Wenngren Christina
Published: February 2017

Transnational organized crime is part and parcel of the modern, globalized economy. The black market has irrefutable influence over both economic and political structures. It corrodes, corrupts, and coopts the institutions with which it comes into contact. Features that arise as a side effect of organized criminal activity also impact economic, social, and political developments. Isolated approaches aimed at counteracting criminal networks have proved ineffective, necessitating a fresh perspective on foreign policy-based solutions.

A central difficulty of researching organized crime is the opaque nature of criminal networks, whose members prefer to operate in the shadows. The underworld does not owe accountability to any outsiders, nor do crime syndicates generally file tax returns. International bodies like the United Nations Office on Drugs and Crime are forced to rely on the reports of member states, which are often subject to distortion. This makes accurate assessment of the extent and impact of organized crime difficult, to say the least.

Part of what makes the black market difficult to combat is the malleable approach of criminal networks. They employ a variety of strategies to pursue their illicit activity and will quickly adapt to the given strength or weakness of their host state. These strategies manifest themselves as either evasion, confrontation, or infiltration of state institutions. All of these strategies undermine legitimate sociopolitical structures, making it imperative to implement effective foreign policy initiatives that fight the trade as a whole.
Hegemony in Foreign Policy
Authors: Lebow Richard Ned , Reich Simon
Published: February 2017

American realists, liberals, journalists, and policymakers speak of American hegemony as if it were an established role, although a threatened one given the rise of China. They describe hegemony as essential to international political and economic stability, and a role that only America can perform. These claims are highly questionable, as there is no evidence that the United States is a hegemon nor that it has provided the benefits American international relations theorists attribute to a hegemon. To the extent these benefits are provided, it is the result of the collective efforts of numerous states, by no means all of them great powers. American assertions of hegemony are viewed with jaundiced, if not hostile, eyes by other states. Hegemony is a fiction, propagated by Americans to gain special privileges, justify an interventionist foreign policy, support the defense industry, and buttress national self-esteem. In practice, the quest for hegemony is a threat, not a prop, to the global order.
Realism in Foreign Policy Analysis
Authors: Wivel Anders
Published: February 2017

Realists explain foreign policy in terms of power politics. They disagree on the exact meaning of power and on how and to what extent politics is likely to influence policy. But they all find that power has a strong materialist component and that the influence of domestic politics on foreign policy is likely to vary with security challenges stemming from the external environment. The relative size of a state’s material resources is likely to influence its ability to set agendas and influence specific decisions and outcomes in international affairs. And the nature of the strategic environment, most importantly whether the security and survival of the state is under immediate threat, is likely to influence the relative weight of domestic influences on foreign policy. In sum, great powers enjoy a bigger external action space in their foreign policies than weaker states, and secure states enjoy a bigger external action space in their foreign policies than insecure states.

Realism is a top-down approach to explaining foreign policy. Realists begin from the anarchic structure of the international system. They argue that the absence of a legitimate monopoly of power in the international system create a strong incentive for states to focus on survival as their primary goal and self-help as the most important means to achieving this goal. However, “survival” and “self-help” may take many forms. These forms are shaped by mechanisms of socialization and competition in the international system and systemic incentives are filtered through the perceptions of foreign policy decision makers and domestic institutions enabling and restraining the ability of decision makers to respond to external incentives. Neoclassical realists combine these factors in order to explain specific foreign policies. Offensive realists and defensive realists focus on the effects of structure on foreign policy, but with contrasting assumptions about the typical behavior of states: defensive realists expect states to pursue balancing policies, whereas offensive realists argue that only by creating an imbalance of power in its own favor will a state be able to maximize its security.

In addition to being an analytical approach for explaining foreign policy, realists often serve as foreign policy advisors or act in the function of public intellectuals problematizing and criticizing foreign policy. This illustrates the potential for realism as an analytical, problem-solving and critical approach to foreign policy analysis. However, it also shows the strains within realism between ambitions of creating general theories, explaining particular foreign policies, and advising on how to make prudent foreign policy decisions.
Physical Activity and Personality Traits
Authors: Rhodes Ryan E. , Boudreau Patrick
Published: February 2017

The physical, psychological, and economic benefits of regular moderate-to-vigorous-intensity physical activity are well substantiated. Unfortunately, few people in developed countries engage in enough physical activity to reap these benefits. Thus, a strong theoretical understanding of what factors are associated with physical activity is warranted in order to create effective and targeted interventions. Social/ecological approaches to understanding physical activity demonstrate the breadth of correlates that encompass intra-individual, inter-individual, environmental, and policy-related variables in physical activity performance. One longstanding intrapersonal correlate of interest is the relationship between personality traits—enduring individual-level differences in tendencies to show consistent patterns of thoughts, feelings, and actions—and physical activity.

Personality trait theories are broad in focus and differ in terms of proposed etiology, yet much of the recent research in physical activity has been with super traits in the five-factor model: neuroticism, extraversion, openness, agreeableness, and conscientiousness. Meta-analytic reviews suggest that conscientiousness and extraversion are positively associated with physical activity with some mixed evidence for a small negative relationship with neuroticism. The effect appears to be most pronounced with vigorous physical activities and less so with lower-intensity lifestyle activities and shows mixed evidence for whether proximal social cognitive variables (intention, self-efficacy) can mediate this relationship. More specific sub-traits show that facets of extraversion (excitement-seeking, activity) or conscientiousness (self-discipline, industriousness/ambition) have larger and more specific associations with particular types of physical activity or moderate key processes like the intention-behavior gap. Furthermore, personality appears to be linked to higher-intensity and adventure activities more than lower-intensity leisure physical activities. Contemporary longitudinal assessments of the bi-directionality of personality and physical activity have begun to advance our understanding of interconnectedness. Interventions that target personality traits to improve physical activity have been relatively understudied but hold some promise when used in tandem with larger theoretical approaches and behavioral change strategies.
Resistance in Popular Culture
Authors: Schuilenburg Marc
Published: February 2017

Much of the existing research on video games seems to stall over the issue of whether or not violence in games is as innocent as is alleged. Scientists are still divided as to whether or not there is a causal link between the behavior of young people and violence in video gaming. Much less discussion is devoted to how cultural and political engagement finds new channels in video games to confront dominant opinions and perceptions in society. However, a more recent body of scientific work considers how the image spaces of video games facilitate new forms of resistance and how this opens up possibilities of social change in our daily lives. In this research, the culture of video gaming is used as a tool for a deeper understanding of resistance in our society. In this context, application of theories about “contagion without contact” can add some new thoughts to the way the virtual world of video games offers possibilities for a politics of resistance in real life. From a historical point of view, the work of the 19th-century French sociologist Gabriel Tarde, one of the first theorists on contagion, can be used to understand more deeply this on-going process by which everyday life recreates itself in its own image, and vice versa. Rather than measuring the amount of violence present in video games (“content analysis”) or identifying causal linkages between media representations of violent imagery and behavior, and subsequent human behavior (“media effect research”), it becomes evident that players of games are not passive recipients, but active interpreters of the reality that arises in and is processed by popular culture.
Witnessing and Victimhood
Authors: Walklate Sandra
Published: February 2017

It is without doubt that the 21st century is marked by ever-present 24-hour media. Mobile phones, iPads, and Wi-Fi networks mean that many people in many different parts of the world are “connected” to each other and to global events as they happen in ways not really imagined less than a century ago. Of course the nature of this connectivity is variable. It dominates more in some parts of the world than others, in urban areas more than rural, among wealthier communities more than poorer ones, and perhaps among younger people more than older people. Such variations notwithstanding, it is the case that the minute-by-minute live reporting of events, as they happen, exposes the nature of those events to people not necessarily close to them or impacted by them, albeit vicariously. Such exposure means that people are potentially witnesses to events and images they would not otherwise have experience of. It is within this context this article considers the concepts of victim, witness, and the linkages between them.

The concept of the witness has a varied history, from its presence in the law, to its connections with religious affiliation, to its legacy in experiences of atrocity. These different historical legacies are suggestive of different claims to victimhood. Simultaneously, these different claims to the status of victim (who constitutes a victim and under what conditions) have become conflated. In mapping the trajectories of each of these concepts, it is possible to discern considerable fuzziness in the relationship between victim and witness, suggestive of a continuum from the victim as witness to the witness as victim. Moreover, when these two concepts are put in such a relationship with each other, it is possible to observe how transgressive capacity takes its toll on people, how to make sense of the issues that concern them, and how best to respond to those concerns. This article considers the questions posed by the relationship between being a victim and being a witness, paying particular attention to who is and who is not considered to have a legitimate claim to victim status, and the role of ever-present media coverage in contributing to such claims and/or even creating them.
The History of Agriculture in Ethiopia
Authors: McCann James C.
Published: February 2017

Ethiopia’s highlands and their lowland peripheries offer a distinctive and, in many ways, ideal setting for human habitation and the evolution of agricultural ecologies. The ranges in climate variability by season and over time framed a sophisticated set of crops, agricultural practices, and local political ecologies. Chief among these was the development and use of the single-tine ox-plow (i.e., the ard or scratch plow) that integrated endemic annual crops with secondary crop introductions and, in some areas, cultivated or intercropped with perennial crops such as ensete and coffee. Animal husbandry to sustain animal traction and pastoral livelihoods in regional ecologies was essential, over time, to regional economies and their political ecologies.

Agricultural patterns existed at the heart of cultural diversities and periods of political conflict and accommodations. In some areas of the south (Sidamo), southeast (Harar highlands), and southwest (Jimma), coffee cultivation complemented annual grain cropping. Yet the plow in its current form as a dominant tool appears in rock painting dating as far back as 500 ad. That technology was both efficient and persistent.

While Ethiopia’s plow agriculture dominated the region’s political ecology over more than two millennia, in the late 20th century Ethiopia’s agrarian economy began an inexorable set of changes. New crops (such as maize), urbanization, and global migration of peoples and commodities (oil seeds, fibers, and grains) brought new seeds, inputs, and pressures to adapt to change, particularly for smallholder farmers and new enterprises. Heavy investments in dams and irrigated agriculture also foretell new agricultural landscapes of riverain areas that will need to coexist with the classic highland smallholder farms. The story of maize in Ethiopia’s agricultural history is emblematic of the struggle between pressures for change and the inertia of tradition felt by farmers. Their agrarian adaptation to new methods, new materials, and a new climate will play itself out in existing geographies and natural contours.
Communism in South Africa
Authors: Filatova Irina
Published: February 2017

The history of communism in South Africa began with the formation in 1921 of the Communist Party of South Africa (CPSA). The party was entirely white, as was the majority of organized labor—its main constituency. The CPSA attempted to fight for equality of black and white workers, but white labor refused to desegregate, and the party’s support among Africans was practically nonexistent. In 1928, the Communist International (Comintern), of which the CPSA was a member, sent it an instruction to work for an “independent native republic.” This slogan helped the party to attract a black membership, but resulted in much infighting.

The CPSA’s position strengthened during World War II, but in 1950, after Afrikaner nationalists came to power, the party was banned. It re-emerged in 1953 as the underground South African Communist Party (SACP). Since then, the party has worked closely with the African National Congress (ANC). Many of its cadres were simultaneously ANC members. In 1955, communists helped to formulate the Freedom Charter, the ANC’s overarching program. In 1960, the SACP launched the armed struggle against apartheid. The ANC took the nascent liberation army under its wing in 1963. In the early 1960s, many party members, including Nelson Mandela, were arrested or forced into exile.

The party had a deep ideological influence on the ANC: from 1969, its ideas on South Africa as a colony of a special type and on the National Democratic Revolution (NDR) have become part of all ANC programs.

After the end of apartheid, communists occupied important positions in all ANC governments. Despite this, many in the SACP have been unhappy with the direction the ANC has taken. However, the party has not contested elections on its own, trying instead to influence ANC policies from inside. This has cost it its reputation as a militant revolutionary party.
The Space Race and American Foreign Relations
Authors: Muir-Harmony Teasel
Published: February 2017

The Soviet Union’s successful launch of the first artificial satellite Sputnik 1 on October 4, 1957, captured global attention and achieved the initial victory in what would soon become known as the space race. This impressive technological feat and its broader implications for Soviet missile capability rattled the confidence of the American public and challenged the credibility of U.S. leadership abroad. With the U.S.S.R.’s launch of Sputnik, and then later the first human spaceflight in 1961, U.S. policymakers feared that the public and political leaders around the world would view communism as a viable and even more dynamic alternative to capitalism, tilting the global balance of power away from the United States and towards the Soviet Union.

Reactions to Sputnik confirmed what members of the U.S. National Security Council had predicted: the image of scientific and technological superiority had very real, far-reaching geopolitical consequences. By signaling Soviet technological and military prowess, Sputnik solidified the link between space exploration and national prestige, setting a course for nationally funded space exploration for years to come. For over a decade, both the Soviet Union and the United States funneled significant financial and personnel resources into achieving impressive firsts in space, as part of a larger effort to win alliances in the Cold War contest for global influence.

From a U.S. vantage point, the space race culminated in the first Moon landing in July 1969. In 1961, President John F. Kennedy proposed Project Apollo, a lunar exploration program, as a tactic for restoring U.S. prestige in the wake of Soviet cosmonaut Yuri Gagarin’s spaceflight and the failure of the Bay of Pigs invasion. To achieve Kennedy’s goal of sending a man to the Moon and returning him safely back to Earth by the end of the decade, the United States mobilized a workforce in the hundreds of thousands. Project Apollo became the most expensive government funded civilian engineering program in U.S. history, at one point stretching to more than 4 percent of the federal budget. The United States’ substantial investment in winning the space race reveals the significant status of soft power in American foreign policy strategy during the Cold War.
Religion and Race in America
Authors: Clark Emily Suzanne
Published: February 2017

Religion and race provide rich categories of analysis for American history. Neither category is stable. They change, shift, and develop in light of historical and cultural contexts. Religion has played a vital role in the construction, deconstruction, and transgression of racial identities and boundaries.

Race is a social concept and a means of classifying people. The “natural” and “inherent” differences between races are human constructs, social taxonomies created by cultures. In American history, the construction of racial identities and racial differences begins with the initial encounters between Europeans, Native Americans, and Africans. Access to and use of religious and political power has shaped how race has been conceived in American history. Racial categories and religious affiliations influenced how groups regarded each other throughout American history, with developments in the colonial period offering prime examples. Enslavement of Africans and their descendants, as well as conquered Native Americans, displayed the power of white Protestants. Even 19th-century American anti-Catholicism and anti-Mormonism intersected racial identifications. At the same time, just as religion has supported racial domination in American history, it also has inspired calls for self-determination among racial minorities, most notably in the 20th century.

With the long shadow of slavery, the power of white supremacy, the emphasis on Native sovereignty, and the civil rights movement, much of the story of religion and race in American history focuses on Americans white, black, and red. However, this is not the whole story. Mexican-Americans and Latinx immigrants bring Catholic and transnational connections, but their presence has prompted xenophobia. Additionally, white Americans sought to restrict the arrival of Asian immigrants both legally and culturally. With the passing of the Immigration and Nationality Act of 1965, the religious, racial, and ethnic diversity of the United States increased further. This religious and racial pluralism in many ways reflects the diversity of America, as does the conflict that comes with it.