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Six considerations for designing and evaluating collaboration in immersive environments
No full textPersons use and respond to various cues and behaviors as part of their daily communication and information exchange with others. When these are obscured or obstructed by the technology, users
tend to experience rifts in collaboration. For this reason, we discuss different group factors and their role in collaboration in immersive environments. By including perspectives from visual and immersive analytics, embodied interaction, social psychology, and collective behavior, we identify common motives in literature that deserve the designer’s attention. We list six considerations for designing and evaluating collaboration in immersive environments. The collection of these considerations could serve to inform future research on the topic.publishe
Latitudinal variation in plant–soil feedbacks : contrasting patterns between the global plant invader Spartina alterniflora and a native competitor in China
No full textPlant–soil feedbacks (PSFs) can strongly influence plant coexistence and invasions of non-native plant species. However, it is unclear how PSFs vary across large biogeographic gradients and influence interactions between native and invasive plant species. Understanding such variation and associated mechanisms will have important implications for the management of invasive plants on large geographical scales. We examined the strength of PSFs in field soils conditioned by a global plant invader Spartina alterniflora and its native competitor Phragmites australis, across the major latitudinal range of S. alterniflora (22.4–37.9°N) in Chinese coastal wetlands. We disentangled the influence of abiotic and biotic drivers underlying PSFs by using soil sterilization (to eliminate microbes) and sterilization + activated carbon addition (to eliminate microbes and secondary chemicals) in a greenhouse experiment. We found that PSFs of native P. australis shifted from neutral/negative to positive with increasing latitude, whereas PSFs of invasive S. alterniflora were positive across latitudes, with little latitudinal variations. Soil sterilization weakened positive PSFs of the invader, but enhanced positive PSFs of native P. australis at lower latitudes, thereby diminishing the latitudinal gradient of PSFs in P. australis. These results suggest that soil biota-mediated PSFs may promote S. alterniflora invasion across latitudes, with a more pronounced role at lower latitudes. Our findings illustrate contrasting latitudinal gradients in PSFs between invasive and native plant competitors, highlighting the importance of considering geographical context when evaluating the role of PSFs in plant invasions and ecological restoration.publishe
The Hadamard Product of Moment Sequences, Diagonal Positivity Preservers, and their Generators
No full textpublishe
Collective moderation of hate, toxicity, and extremity in online discussions
No full textIn the digital age, hate speech poses a threat to the functioning of social media platforms as spaces for public discourse. Top-down approaches to moderate hate speech encounter difficulties due to conflicts with freedom of expression and issues of scalability. Counter speech, a form of collective moderation by citizens, has emerged as a potential remedy. Here, we aim to investigate which counter speech strategies are most effective in reducing the prevalence of hate, toxicity, and extremity on online platforms. We analyze more than 130,000 discussions on German Twitter starting at the peak of the migrant crisis in 2015 and extending over 4 years. We use human annotation and machine learning classifiers to identify argumentation strategies, ingroup and outgroup references, emotional tone, and different measures of discourse quality. Using matching and time-series analyses we discern the effectiveness of naturally observed counter speech strategies on the microlevel (individual tweet pairs), mesolevel (entire discussions) and macrolevel (over days). We find that expressing straightforward opinions, even if not factual but devoid of insults, results in the least subsequent hate, toxicity, and extremity over all levels of analyses. This strategy complements currently recommended counter speech strategies and is easy for citizens to engage in. Sarcasm can also be effective in improving discourse quality, especially in the presence of organized extreme groups. Going beyond one-shot analyses on smaller samples prevalent in most prior studies, our findings have implications for the successful management of public online spaces through collective civic moderation.publishe
Assessing Data Quality in the Age of Digital Social Research : A Systematic Review
No full textWhile survey data has long been the focus of quantitative social science analyses, observational and content data, although long-established, are gaining renewed attention; especially when this type of data is obtained by and for observing digital content and behavior. Today, digital technologies allow social scientists to track “everyday behavior” and to extract opinions from public discussions on online platforms. These new types of digital traces of human behavior, together with computational methods for analyzing them, have opened new avenues for analyzing, understanding, and addressing social science research questions. However, even the most innovative and extensive amounts of data are hollow if they are not of high quality. But what does data quality mean for modern social science data? To investigate this rather abstract question the present study focuses on four objectives. First, we provide researchers with a decision tree to identify appropriate data quality frameworks for a given use case. Second, we determine which data types and quality dimensions are already addressed in the existing frameworks. Third, we identify gaps with respect to different data types and data quality dimensions within the existing frameworks which need to be filled. And fourth, we provide a detailed literature overview for the intrinsic and extrinsic perspectives on data quality. By conducting a systematic literature review based on text mining methods, we identified and reviewed 58 data quality frameworks. In our decision tree, the three categories, namely, data type, the perspective it takes, and its level of granularity, help researchers to find appropriate data quality frameworks. We, furthermore, discovered gaps in the available frameworks with respect to visual and especially linked data and point out in our review that even famous frameworks might miss important aspects. The article ends with a critical discussion of the current state of the literature and potential future research avenues.publishe
A Complementarity‐Based Approach to De Novo Binder Design
No full textDe novo design of binders capable of targeting arbitrarily selected epitopes remains a substantial challenge. Here, a generalizable computational strategy is presented to design site‐specific protein binders, obviating steps of extensive empirical optimization or in vitro screening. The dock‐and‐design pipeline retrieves complementary scaffolds from a protein structure database to a given query epitope, where the scaffold is mutated to carve a binding site de novo . The docking step utilizes a novel fingerprint that greatly simplifies and accelerates the surface complementarity evaluation. As proof‐of‐concept, we designed protein binders to target three distinct epitopes on two different oncogenic targets; vascular endothelial growth factor (VEGF) and interleukin‐7 receptor‐α (IL‐7Rα). Experimental characterization of only 24 candidates identified nanomolar binders against each of the target epitopes, where the binders belonged to five different folds. Several designs were active in vitro. Moreover, anti‐VEGF designs showed tumor‐inhibiting activity in vivo, highlighting their therapeutic potential.publishe
Wild orangutans maintain sleep homeostasis through napping, counterbalancing socio-ecological factors that interfere with their sleep
No full textSleep is a vital physiological process that lab-based studies of model species, including humans, have shown is homeostatically regulated—i.e., pressure to sleep builds during wakefulness and dissipates during sleep. However, how wild animals maintain sleep homeostasis and how socio-ecological pressures interfere with their sleep remain understudied. Here, we investigated sleep homeostasis and the factors that influence sleep duration among wild Sumatran orangutans (Pongo abelii), leveraging a comprehensive long-term dataset of their behavior, sociality, and ecology. We quantified sleep in 53 adult individuals using the time that an individual spent in a sleeping nest—i.e., its sleep period—as an indicator of time spent sleeping. We found that, after shorter nighttime sleep periods, orangutans’ next-day cumulative nap period duration was longer and that shorter nap periods were associated with a higher number of naps on the same day. We also found that orangutans had shorter sleep periods (night and day) when they associated with more conspecifics. Orangutans also had shorter nighttime sleep periods when they traveled farther the day before, and they had longer cumulative nap periods on days when (1) they ate fewer calories, (2) the ambient temperature was cooler, and (3) it rained. Our results suggest that multiple factors shape wild orangutans’ sleep behavior and that orangutans compensate for lost sleep via daytime napping. This supports the hypothesis that social and ecological pressures interfere with sleep among wild animals and that they must balance the costs and benefits of sleep with those of other critical activities.publishe
Exclamation, intensity, and emotive assertion
No full textIn this paper, we present a novel analysis of exclamations as assertions equivalent to particular uses of declarative sentences with emotive verbs. Focusing on wh-exclamatives and declarative exclamations, we offer a wide range of arguments for why they are both assertive. We further argue that like emotive verbs, exclamations convey a presupposition not of factivity but of subjective veridicality anchored to the speaker, and assert the emotion (of surprise, amazement, or a negative emotion). Our analysis proposes a syntax-semantics for exclamations without a speech act operator, and exclamativity surfaces as an attitude rather than a speech act. This seems to be well motivated by the Greek, German as well as English facts we examine in the paper. Illocutionary operator approaches cannot capture the facts discussed here, and they also fail to determine precisely what the exclamative force might be.publishe
