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The Berkeley Research Impact Initiative (BRII) provides funding to Berkeley authors (current faculty members, post-docs, graduate students, researchers) and publishers (Centers, Organized Research Units, and
Departments) to make their publications free to all readers immediately upon publication. The purpose of the BRII program is to foster broad public access to the work of Berkeley scholars by encouraging the Berkeley
community to take advantage of open access (OA) publishing opportunities. For more information about the program see the BRII website:

Durability of effects from short-term economic incentives for clinic attendance among HIV positive adults in Tanzania: long-term follow-up of a randomised controlled trial


Introduction Conditional economic incentives are shown to promote medication adherence across a range of health conditions and settings; however, any long-term harms or benefits from these time-limited interventions remainlargely unevaluated. We assessed 2–3 years outcomes from a 6-month incentive programme in Tanzania that originally improved short-term retention in HIV care and medication possession.Methods We traced former participants in a 2013–2016 trial, which randomised 800 food-insecure adults starting HIV treatment at three clinics to receive eitherusual care (control) or up to 6 months of cash or food transfers (~US$11/month) contingent on timely attendance at monthly clinic appointments. The primaryintention-to-treat analysis estimated 24-month and 36-month marginal risk differences (RD) between incentive and control groups for retention in care and all-cause mortality, using multiple imputation for a minority of missing outcomes. We also estimated mortality HRs from time-stratified Cox regression.Results From 3 March 2018 to 19 September 2019, we determined 36-month retention and mortality statusesfor 737 (92%) and 700 (88%) participants, respectively. Overall, approximately 660 (83%) participants were in care at 36 months while 43 (5%) had died. Therewere no differences between groups in retention at 24 months (86.5% intervention vs 84.4% control, RD 2.1,95% CI −5.2 to 9.3) or 36 months (83.3% vs 77.8%, RD 5.6, –2.7 to 13.8), nor in mortality at either time point. The intervention group had a lower rate of death during the first 18 months (HR 0.27, 95% CI 0.10 to 0.74); mortality was similar thereafter (HR 1.13, 95% CI 0.33to 3.79).Conclusion These findings confirm that incentives are a safe and effective tool to promote short-term adherence and potentially avert early deaths at thecritical time of HIV treatment initiation. Complementary strategies are recommended to sustain lifelongretention in HIV care.Trial registration number NCT01957917

Implicit Standardization in a Minority Language Community: Real-Time Syntactic Change among Hasidic Yiddish Writers


The recent turn to “big data” from social media corpora has enabled sociolinguists to investigate patterns of language variation and change at unprecedented scales. However, research in this paradigm has been slow to address variable phenomena in minority languages, where data scarcity and the absence of computational tools (e.g., taggers, parsers) often present significant barriers to entry. This article analyzes socio-syntactic variation in one minority language variety, Hasidic Yiddish, focusing on a variable for which tokens can be identified in raw text using purely morphological criteria. In non-finite particle verbs, the overt tense marker tsu (cf. English to, German zu) is variably realized either between the preverbal particle and verb (e.g., oyf-tsu-es-n up-to-eat-INF ‘to eat up’; the conservative variant) or before both elements (tsu oyf-es-n to up-eat-INF; the innovative variant). Nearly 38,000 tokens of non-finite particle verbs were extracted from the popular Hasidic Yiddish discussion forum Kave Shtiebel (the ‘coffee room’; A mixed-effects regression analysis reveals that despite a forum-wide favoring effect for the innovative variant, users favor the conservative variant the longer their accounts remain open and active. This process of rapid implicit standardization is supported by ethnographic evidence highlighting the spread of language norms among Hasidic writers on the internet, most of whom did not have the opportunity to express themselves in written Yiddish prior to the advent of social media.

A Tale of Winglets: Evolution of Flight Morphology in Stick Insects


The evolutionary transition between winglessness and a full-winged morphology requires selective advantage for intermediate forms. Conversely, repeated secondary wing reductions among the pterygotes indicates relaxation of such selection. However, evolutionary trajectories of such transitions are not well-characterized. The stick insects (Phasmatodea) exhibit diverse wing sizes at both interspecific and intersexual levels, and thus provide a system for examining how selection on flight capability, along with other selective forces, drives the evolution of flight-related morphology. Here, we examine variation in relevant morphology for stick insects using data from 1,100+ individuals representing 765 species. Although wing size varies along a continuous spectrum, taxa with either long or miniaturized wings are the most common, whereas those with intermediate-sized wings are relatively rare. In a morphological space defined by wing and body size, the aerodynamically relevant parameter termed wing loading (the average pressure exerted on the air by the wings) varies according to sex-specific scaling laws; volant but also flightless forms are the most common outcomes in both sexes. Using phylogenetically-informed analyses, we show that relative wing size and body size are inversely correlated in long-winged insects regardless of sexual differences in morphology and ecology. These results demonstrate the diversity of flight-related morphology in stick insects, and also provide a general framework for addressing evolutionary coupling between wing and body dimensions. We also find indirect evidence for a “fitness valley” associated with intermediate-sized wings, suggesting relatively rapid evolutionary transitions between wingless and volant forms.

Spectrum-Wide Quantum Criticality at the Surface of Class AIII Topological Phases: An "Energy Stack"� of Integer Quantum Hall Plateau Transitions


In the absence of spin-orbit coupling, the conventional dogma of Anderson localization asserts that all states localize in two dimensions, with a glaring exception: the quantum Hall plateau transition (QHPT). In that case, the localization length diverges and interference-induced quantum-critical spatial fluctuations appear at all length scales. Normally, QHPT states occur only at isolated energies; accessing them therefore requires fine-tuning of the electron density or magnetic field. In this paper we show that QHPT states can be realized throughout an energy continuum, i.e., as an “energy stack” of critical states wherein each state in the stack exhibits QHPT phenomenology. The stacking occurs without fine-tuning at the surface of a class AIII topological phase, where it is protected by U(1) and (anomalous) chiral or time-reversal symmetries. Spectrum-wide criticality is diagnosed by comparing numerics to universal results for the longitudinal Landauer conductance and wave function multifractality at the QHPT. Results are obtained from an effective 2D surface field theory and from a bulk 3D lattice model. We demonstrate that the stacking of quantum-critical QHPT states is a robust phenomenon that occurs for AIII topological phases with both odd and even winding numbers. The latter conclusion may have important implications for the still poorly understood logarithmic conformal field theory believed to describe the QHPT.

Global agricultural economic water scarcity


Water scarcity raises major concerns on the sustainable future of humanity and the conservation of important ecosystem functions. To meet the increasing food demand without expanding cultivated areas, agriculture will likely need to introduce irrigation in croplands that are currently rain-fed but where enough water would be available for irrigation. “Agricultural economic water scarcity” is, here, defined as lack of irrigation due to limited institutional and economic capacity instead of hydrologic constraints. To date, the location and productivity potential of economically water scarce croplands remain unknown. We develop a monthly agrohydrological analysis to map agricultural regions affected by agricultural economic water scarcity. We find these regions account for up to 25% of the global croplands, mostly across Sub-Saharan Africa, Eastern Europe, and Central Asia. Sustainable irrigation of economically water scarce croplands could feed an additional 840 million people while preventing further aggravation of blue water scarcity.

Why Does Therapy Work? An Idiographic Approach to Explore Mechanisms of Change Over the Course of Psychotherapy Using Digital Assessments


Background and Objective(s): While psychotherapy treatments are largely effective, the processes and mechanisms underlying such positive changes remain somewhat unknown. Focusing on a single participant from a treatment outcome study that used a modular-based cognitive behavior therapy protocol, this article aims to answer this question by identifying changes in specific symptomatology over the course of the treatment. Using quantitative data derived from digital health methodology, we analyzed whether a given therapeutic intervention was related to downstream effects in predicted symptom domains, to assess the accuracy of our interventions.

Methods: This case study employed an observational N-of-1 study design. The participant (n = 1) was a female in the age range of 25–35 years. Using digital health data from ambulatory assessment surveys completed prior to and during therapy, separate linear regression analyses were conducted to assess if hypothesized treatment targets reduced after a given module, or intervention.

Results: Support was found for some of the hypothesized quantitative changes (e.g., decreases in avoidance after exposures module), yet not for others (e.g., decreases in rumination following the mindfulness module).

Conclusion: We present data and results from our analyses to offer an example of a novel design that may allow for a greater understanding of the nature of symptom changes with increased granularity throughout the course of a psychological treatment from the use of digital health tools.

Topography and human pressure in mountain ranges alter expected species responses to climate change


ArticleOpen AccessPublished: 24 April 2020Topography and human pressure in mountain ranges alter expected species responses to climate changePaul R. ElsenWilliam B. Monahan & Adina M. Merenlender 

Nature Communications volume 11, Article number: 1974 (2020) Cite this article

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Climate change is leading to widespread elevational shifts thought to increase species extinction risk in mountains. We integrate digital elevation models with a metric of human pressure to examine changes in the amount of intact land area available for species undergoing elevational range shifts in all major mountain ranges globally (n = 1010). Nearly 60% of mountainous area is under intense human pressure, predominantly at low elevations and mountain bases. Consequently, upslope range shifts generally resulted in modeled species at lower elevations expanding into areas of lower human pressure and, due to complex topography, encountering more intact land area relative to their starting position. Such gains were often attenuated at high elevations as land-use constraints diminished and topographic constraints increased. Integrating patterns of topography and human pressure is essential for accurate species vulnerability assessments under climate change, as priorities for protecting, connecting, and restoring mountain landscapes may otherwise be misguided.

Patterns of coyote predation on sheep in California: A socio-ecological approach to mapping risk of livestock-predator conflict


Conflict between livestock producers and wild predators is a central driver of large predator declines and simultaneously may imperil the lives and livelihoods of livestock producers. There is a growing recognition that livestock–predator conflict is a socio‐ecological problem, but few case studies exist to guide conflict research and management from this point of view. Here we present a case study of coyote‐sheep predation on a California ranch in which we combine methods from the rapidly growing field of predation risk modeling with participatory mapping of perceptions of predation risk. Our findings reveal an important selection bias that may occur when producer perceptions and decisions are excluded from ecological methods of studying conflict. We further demonstrate how producer inputs, participatory mapping, and ecological modeling of conflict can inform one another in understanding patterns, drivers, and management opportunities for livestock–predator conflict. Finally, we make recommendations for improving the interoperability of ecological and social data about predation risk. Collectively our methods offer a socio‐ecological approach that fills important research gaps and offers guidance to future research.

Materials sovereignty: Pathways for shaping nanotechnology design


People in contemporary industrial societies encounter countless novel materials that did not exist previously, many of which present risks to health and environment. In this article, we build on the concept of “materials sovereignty” as the right of people to use and be surrounded by environmentally benign, non-toxic, and renewing materials in their everyday lives. As a rights-based approach, materials sovereignty may help change the politics of governing materials. We suggest that social movements that explicitly base interventions into design on materials sovereignty may be better able to gain traction in changing industrial production. We consider the case of nanotechnology as a particularly challenging field for social movement intervention. We review several pathways that have been used by social movement organizations in attempts to influence the development of nanomaterials, but which have met with limited success. We more closely examine three participatory pathways through which social movements could intervene more directly into material design: participatory technology assessment, collaboration with industry, and co-design. We identify three key elements of materials sovereignty: participatory knowledge systems, which create multi-directional flows of knowledge and agency; the embedding of citizen voices into design processes; and building accountability systems. Of the pathways we examine here, co-design appears to be the most promising from a theoretical and ethical perspective, but there remain significant institutional and organizational challenges for bringing it into practice.

Partial migration alters population ecology and food chain length: evidence from a salmonid fish


Many migratory species, from monarch butterflies to wildebeest, express partial migration, where only a subset of a population migrates. This intraspecific variation is likely to have large ecological consequences. We studied the ecological consequences of partial migration in a salmonid fish, Oncorhynchus mykiss , in coastal streams in California, USA. One ecotype, steelhead trout, migrates to the ocean, whereas the other, rainbow trout, completes its lifecycle in freshwater. Migration has a strong genetic basis in O. mykiss . In one stream, we found differences in the frequency of migration‐linked genotypes below and above a waterfall barrier (migratory allele frequency of 60% below vs. 31% above). Below the waterfall, in the migratory‐dominated region, the density of young fish (<1 yr old) was approximately twice that in the resident‐dominated region above the waterfall (0.46 vs. 0.26 individuals/m2, respectively), presumably reflecting the higher fecundity of migratory females. Additionally, there were half as many older fish (>1 yr old) in pools downstream of the waterfall (0.05 vs. 0.13 individuals/m2). In a second stream, between‐year variation in the dominance of migratory vs. resident fish allowed us to explore differences in fish density and size structure through time, and we found a consistent pattern. In brief, when migratory genotypes dominated, we found higher densities of young fish and lower densities of older fish, resulting in a simpler size structure, compared to when resident genotypes dominated. Moreover, large resident trout had a slightly higher trophic position than young fish (3.92 vs. 3.42 in one creek and 3.77 vs. 3.17 in the other), quantified with stable isotope data. The difference in fish size structure did not generate trophic cascades. Partial migration is widespread among migratory populations, as is phenotypic divergence between resident and migratory forms, suggesting the potential for widespread ecological effects arising from this common form of intraspecific variation.