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Social-ecological feedbacks drive tipping points in farming system diversification
No full textThe emergence and impact of tipping points have garnered significant interest in both the social and natural sciences. Despite widespread recognition of the importance of feedbacks between human and natural systems, it is often assumed that the observed nonlinear dynamics in these coupled systems rests within either the underlying human or natural processes rather than the rates at which they interact. Using adoption of agricultural diversification practices as a case study, we show how two stable management paradigms (one dominated by conventional, homogeneous practices and the other by diversified practices) can emerge purely from temporal feedback between human decisions and ecological responses. We explore how this temporal mechanism of tipping points provides insight into designing more effective interventions that promote farmers\u27 transitions toward sustainable agriculture. Moreover, we present a flexible modeling framework that could be applied to other cases as well as questions in social-ecological systems research and environmental policy design
Beyond Bilingualism: A Linguistically Expansive Orientation to Two-Way Immersion
No full textThis article explores the possibilities of a linguistically expansive orientation to two-way immersion (TWI), a bilingual model that has traditionally adopted a “double monolingual” approach to bilingual learning/ers. To illustrate an expansive perspective, we present two case studies undertaken at the same bilingual school that explored strategies for fostering more flexible understandings of students’ linguistic repertoires. Findings from case study one reveal that student identities are more dynamic and contextually-oriented than typically understood within TWI, while also demonstrating that student sense-making can reflect the program’s narrow lens on bilingualism. Findings from case study two illustrate how, when teachers engage students in multilingual writing, meaningful contexts are created for encountering diversity and for expanding and evolving their linguistic repertoires. We argue that a linguistically expansive orientation invites teachers to move beyond language separation in TWI and, in doing so, make space for and affirm students’ dynamic languaging and dynamically lingual identities
UV to NIR Down-Shifting in Yb\u3csup\u3e3+\u3c/sup\u3e-Doped Phosphate Glass via Divalent Tin Centers
Get PDFThe conversion of ultraviolet (UV) to near-infrared (NIR) photons is demonstrated for the first time in Yb3+-containing glass via Sn2+. Glasses with barium phosphate matrix were prepared by melt-quenching adding 2 mol % Yb2O3 alongside SnO up to 10 mol %. The investigation encompassed X-ray diffraction (XRD), UV-vis-NIR absorption, 119Sn Mössbauer spectroscopy, and photoluminescence (PL) spectroscopy measurements with emission dynamics assessment. XRD data showed that the amorphous nature of the glasses is maintained within the range of dopant concentrations considered, while the optical absorption, 119Sn Mössbauer, and PL data supported the occurrence of divalent tin centers. The NIR PL data showed that exciting Sn2+ centers around 290 nm results in the NIR emission from Yb3+ near 1000 nm which becomes more intense with the increase in SnO. The Yb3+ decay curves revealed a rise time for the 2F5/2 emitting level followed by a single exponential decay. An energy transfer process proceeding via charge transfer states involving tin (donor) and ytterbium (acceptor) was proposed to account for the enhanced UV-excited NIR emission from Yb3+ ions
Trawl impacts on the relative status of biotic communities of seabed sedimentary habitats in 24 regions worldwide
Get PDFBottom trawling is widespread globally and impacts seabed habitats. However, risks from trawling remain unquantified at large scales in most regions. We address these issues by synthesizing evidence on the impacts of different trawl-gear types, seabed recovery rates, and spatial distributions of trawling intensity in a quantitative indicator of biotic status (relative amount of pretrawling biota) for sedimentary habitats, where most bottom-trawling occurs, in 24 regions worldwide. Regional average status relative to an untrawled state (=1) was high (\u3e0.9) in 15 regions, but \u3c0.7 in three (European) regions and only 0.25 in the Adriatic Sea. Across all regions, 66% of seabed area was not trawled (status = 1), 1.5% was depleted (status = 0), and 93% had status \u3e 0.8. These assessments are first order, based on parameters estimated with uncertainty from meta-analyses; we recommend regional analyses to refine parameters for local specificity. Nevertheless, our results are sufficiently robust to highlight regions needing more effective management to reduce exploitation and improve stock sustainability and seabed environmental status—while also showing seabed status was high (\u3e0.95) in regions where catches of trawled fish stocks meet accepted benchmarks for sustainable exploitation, demonstrating that environmental benefits accrue from effective fisheries management. Furthermore, regional seabed status was related to the proportional area swept by trawling, enabling preliminary predictions of regional status when only the total amount of trawling is known. This research advances seascape-scale understanding of trawl impacts in regions around the world, enables quantitative assessment of sustainability risks, and facilitates implementation of an ecosystem approach to trawl fisheries management globally
Tinder use, gender, and the psychosocial functioning of young adults
Get PDFTinder is a mobile dating app where users evaluate possible matches based primarily on posted photos; limited content is provided as to who each user is. Thus, appearance becomes paramount in users’ decisions about who to swipe left (i.e., reject) or swipe right (i.e., approve). As such, and consistent with objectification theory, men and women who use this mobile app are treated as objects that are viewed, rated, used, and, in many instances, disposed of. Therefore, in a sample 18-34-year-old men (n=187) and women (n=547), we examined Tinder use and gender in relation to internalization, physical appearance comparison, body satisfaction, self-esteem, perceived sociocultural pressures, depression, negative mood, body surveillance, body shame, body appreciation, and dietary intent. A series of MANCOVAs were used to examine the relation of gender and Tinder use to the outcomes. Regardless of gender, Tinder use (vs. nonuse) was associated with more distress across a range of measures, including sociocultural pressures, internalization of appearance ideals, body image concerns, and negative affect. Tinder use, however, was not related to psychological well-being or eating pathology. These findings extend previous studies and affirm the potentially deleterious environment that exists for Tinder users
Detecting population regulation of winter flounder from noisy data
No full textYear-class size of marine fish is thought to be determined during the first year of life, with density-dependent mortality occuring during the larval or juvenile stages. However, investigations of such dynamics are often limited by data availability. To test this paradigm for winter flounder (Pseudopleuronectes americanus) in Narragansett Bay, Rhode Island, the abundances of 29 year classes moving through seven life stages were analyzed with a novel extension of key-factor analysis. Evidence of density dependence was identified between the egg and July young-of-the-year stages and high process-error variance was detected throughout the life cycle, suggesting year-class size is not fully determined until age-2. However, the first summer appeared to be a critical life stage for winter flounder, during which high temperatures, hypoxia, and predator abundance contributed to increased mortality rates behind a long-term population decline. Due to its general data requirements, the key-factor analysis method developed here may be applied to other aquatic populations to identify the impacts of external stressors at particular life stages and the degree to which they are compensated by density-dependent processes
Pharmacist-Administered Influenza Vaccination in Children and Corresponding Regulations
Get PDFIn our retrospective cohort study, we evaluated trends in pharmacist-administered pediatric influenza vaccination rates in the United States and corresponding state-level pharmacist pediatric vaccination authorization models, including minimum age requirements, vaccination protocols, and/or prescription requirements. An administrative health claims database was used to capture influenza vaccinations in children less than 18 years old with 1 year of continuous enrollment and joinpoint regression was used to assess trends. Of the 3,937,376 pediatric influenza vaccinations identified over the study period, only 3.2% were pharmacist-administered (87.7% pediatrician offices, 2.3% convenience care clinics, 0.8% emergency care, and 6.0% other locations). Pharmacist-administered pediatric influenza vaccination was more commonly observed in older children (mean age 12.65 ± 3.26 years) and increased significantly by 19.2% annually over the study period (95% confidence interval 9.2%-30.2%, p \u3c 0.05). The Northeast, with more restrictive authorization models, represented only 2.2% (n = 2816) of all pharmacist-administered pediatric influenza vaccinations. Utilization of pharmacist-administered pediatric influenza vaccination remains low. Providing children with greater access to vaccination with less restrictions may increase overall vaccination rates. Due to the COVID-19 pandemic and the Public Readiness and Emergency Preparedness Act, pharmacists will play a major role in vaccinating children
Consumers’ Subjective Well-being in Brazil: Suggested Extensions for Researching a Market with Continental Dimensions
Get PDFThis commentary starts by recognizing, in the lead article of this issue, the importance of studying empirically the relationships between marketplace activities and consumers\u27 perceived subjective well-being in Brazil. The commentary then presents a number of ways in which future research studies of this type can be strengthened, in terms of geographical coverage, methods employed and analytical-interpretive tools used. The commentary also offers literature links to a variety of consumption modes, from minimalist to hedonic; pointing out that subjective well-being is influenced by these styles/modes of consumption