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1.
Ecol Appl ; 31(2): e2242, 2021 03.
Article in English | MEDLINE | ID: mdl-33098736

ABSTRACT

Spatial gradients in population growth, such as across latitudinal or elevational gradients, are often assumed to primarily be driven by variation in climate, and are frequently used to infer species' responses to climate change. Here, we use a novel demographic, mixed-model approach to dissect the contributions of climate variables vs. other latitudinal or local site effects on spatiotemporal variation in population performance in three perennial bunchgrasses. For all three species, we find that performance of local populations decreases with warmer and drier conditions, despite latitudinal trends of decreasing population growth toward the cooler and wetter northern portion of each species' range. Thus, latitudinal gradients in performance are not predictive of either local or species-wide responses to climate. This pattern could be common, as many environmental drivers, such as habitat quality or species' interactions, are likely to vary with latitude or elevation, and thus influence or oppose climate responses.


Subject(s)
Climate Change , Population Growth , Ecosystem
2.
J Am Chem Soc ; 142(15): 7179-7189, 2020 04 15.
Article in English | MEDLINE | ID: mdl-32202109

ABSTRACT

Electrophilic halofunctionalization reactions have undergone a resurgence sparked by recent discoveries in the field of catalytic asymmetric halocyclizations. To build mechanistic understanding of these asymmetric transformations, a toolbox of analytical methods has been deployed, addressing the roles of catalyst, electrophile (halenium donor), and nucleophile in determining rates and stereopreferences. The test reaction, (DHQD)2PHAL-catalyzed chlorocyclization of 4-arylpent-4-enoic acid with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH), is revealed to be first order in catalyst and chlorenium ion donor and zero order in alkenoic acid substrate under synthetically relevant conditions. The simplest interpretation is that rapid substrate-catalyst binding precedes rate-limiting chlorenium attack, controlling the face selectivity of both chlorine attack and lactone closure. ROESY and DFT studies, aided by crystal structures of carboxylic acids bound by the catalyst, point to a plausible resting state of the catalyst-substrate complex predisposed for asymmetric chlorolactonization. As revealed by our earlier labeling studies, these findings suggest modes of binding in the (DHQD)2PHAL chiral pocket that explain the system's remarkable control over rate- and enantioselection-determining events. Though a comprehensive modeling analysis is beyond the scope of the present work, quantum chemical analysis of the fragments' interactions and candidate reaction paths point to a one-step concerted process, with the nucleophile playing a critical role in activating the olefin for concomitant electrophilic attack.


Subject(s)
Lactones/chemistry , Catalysis , Molecular Structure , Stereoisomerism
3.
J Acoust Soc Am ; 147(1): 616, 2020 01.
Article in English | MEDLINE | ID: mdl-32007017

ABSTRACT

Regional linguistic variation is a widely known characteristic of American English, with the American South as one of the many foci. However, in much of this literature, Appalachia is lumped together with other Southern varieties. Further, the vast sociolinguistic literature has documented intra-regional variation along socio-indexical lines. However, most variation studies have focused on vocalic variation at the expense of other sources of variation, which may have different patterns and meanings. The present study was designed to explore intonational variation in conversational speech in two varieties of American English: Appalachian and Southern. Additionally, the intra-regional variation in intonation present in Appalachian English was explored considering the rootedness (local place-based attachment) of speakers. The results revealed significant effects of regional dialect on both the quantitative and qualitative realization of pitch accent. Further, intra-regional variation was significantly impacted by socio-indexical aspects, including rootedness, of individual speakers. The findings from this study demonstrate that both region and socio-indexical features are expressed intonationally and also provide motivation for additional exploration of intonational variation across and within the regional varieties of American English.

4.
Lancet ; 391(10121): 700-708, 2018 02 17.
Article in English | MEDLINE | ID: mdl-29054555

ABSTRACT

The 2013-16 Ebola virus disease outbreak in west Africa was associated with unprecedented challenges in the provision of care to patients with Ebola virus disease, including absence of pre-existing isolation and treatment facilities, patients' reluctance to present for medical care, and limitations in the provision of supportive medical care. Case fatality rates in west Africa were initially greater than 70%, but decreased with improvements in supportive care. To inform optimal care in a future outbreak of Ebola virus disease, we employed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology to develop evidence-based guidelines for the delivery of supportive care to patients admitted to Ebola treatment units. Key recommendations include administration of oral and, as necessary, intravenous hydration; systematic monitoring of vital signs and volume status; availability of key biochemical testing; adequate staffing ratios; and availability of analgesics, including opioids, for pain relief.


Subject(s)
Disease Outbreaks , Evidence-Based Medicine/methods , Hemorrhagic Fever, Ebola/epidemiology , Patient Acceptance of Health Care/psychology , Africa, Western/epidemiology , Disease Management , Health Facilities , Hemorrhagic Fever, Ebola/psychology , Hospitalization , Humans , Monitoring, Physiologic , Pain Management , Practice Guidelines as Topic
6.
J Acoust Soc Am ; 136(5): 2747-50, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25373974

ABSTRACT

Effects on the slope of introducing error in the F2 Hz values in locus equations (LEs) and of using fewer than ten vowels were investigated. For each of the initial consonants /b, d, g/, 2000 simulated sets were generated using Monte Carlo techniques. The sets were altered with 50, 100, or 200 Hz error being randomly applied to each F2 value within a set. Selected vowels were then removed from the sets and the effects on the slopes were measured. Results suggest that the LE slopes are generally resistant to error and reduced number of vowels. Effects of adding 50 Hz of random error to the F2 values in sets using eight or ten vowels were minimal, yielding a mean absolute change in slope less than 0.07.

7.
Lang Speech ; 67(1): 140-165, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37161280

ABSTRACT

Expanding on psycholinguistic research on linguistic adaptation, the phenomenon whereby speakers change how they comprehend or produce structures as a result of cumulative exposure to less frequent or unfamiliar linguistic structures, this study asked whether speakers can learn semantic and syntactic properties of the American English vernacular negative auxiliary inversion (NAI) structure (e.g., didn't everybody eat, meaning "not everybody ate") during the course of an experiment. Formal theoretical analyses of NAI informed the design of a task in which American English-speaking participants unfamiliar with this structure were exposed to NAI sentences in either semantically ambiguous or unambiguous contexts. Participants rapidly adapted to the interpretive properties of NAI, selecting responses similar to what would be expected of a native speaker after only limited exposure to semantically ambiguous input. On a separate ratings task, participants displayed knowledge of syntactic restrictions on NAI subject type, despite having no previous exposure. We discuss the results in the context of other experimental studies of adaptation and suggest the implementation of top-down strategies via analogy to other familiar structure types as possible explanations for the behaviors observed in this study. The study illustrates the value of integrating insights from formal theoretical research and psycholinguistic methods in research on adaptation and highlights the need for more interdisciplinary and cross-disciplinary work in both experimental and naturalistic contexts to understand this phenomenon.


Subject(s)
Language , Semantics , Humans , Linguistics , Psycholinguistics , Learning
8.
Evol Anthropol ; 22(3): 103-10, 2013.
Article in English | MEDLINE | ID: mdl-23776046

ABSTRACT

In the ancient American Southwest, use of the bow developed relatively rapidly among Pueblo people by the fifth century AD. This new technology replaced the millennia-old atlatl and dart weaponry system. Roughly 150 years later in the AD 600s, Pueblo socioeconomic organization began to evolve rapidly, as many groups adopted a much more sedentary life. Multiple factors converged to allow this sedentary pattern to emerge, but the role of the bow in this process has not been fully explored. In this paper, we trace the development of the bow and discuss its role as sedentism emerged and social changes occurred in ancient Puebloan society from the fifth through seventh centuries AD.


Subject(s)
Population Dynamics , Social Change , Technology/history , Warfare , Archaeology , History, Ancient , History, Medieval , Humans , Indians, North American/history , Southwestern United States
9.
Plant Environ Interact ; 4(2): 97-113, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37288163

ABSTRACT

Danthonia californica Bolander (Poaceae)is a native perennial bunchgrass commonly used in the restoration of prairie ecosystems in the western United States. Plants of this species simultaneously produce both chasmogamous (potentially outcrossed) and cleistogamous (obligately self-fertilized) seeds. Restoration practitioners almost exclusively use chasmogamous seeds for outplanting, which are predicted to perform better in novel environments due to their greater genetic diversity. Meanwhile, cleistogamous seeds may exhibit greater local adaptation to the conditions in which the maternal plant exists. We performed a common garden experiment at two sites in the Willamette Valley, Oregon, to assess the influence of seed type and source population (eight populations from a latitudinal gradient) on seedling emergence and found no evidence of local adaptation for either seed type. Cleistogamous seeds outperformed chasmogamous seeds, regardless of whether seeds were sourced directly from the common gardens (local seeds) or other populations (nonlocal seeds). Furthermore, average seed weight had a strong positive effect on seedling emergence, despite the fact that chasmogamous seeds had significantly greater mass than cleistogamous seeds. At one common garden, we observed that seeds of both types sourced from north of our planting site performed significantly better than local or southern-sourced seeds. We also found a significant seed type and distance-dependent interaction, with cleistogamous seedling emergence peaking approximately 125 km from the garden. These results suggest that cleistogamous seeds should be considered for greater use in D. californica restoration.

10.
Am J Speech Lang Pathol ; 30(5): 1962-1972, 2021 09 23.
Article in English | MEDLINE | ID: mdl-34432983

ABSTRACT

Purpose Despite the increased awareness that all dialects are valid linguistic forms, perceptions of African American English (AAE) use are often negative in the general population. Students training for careers as speech-language pathologists (SLPs) are required to have coursework relating to cultural and linguistic diversity. However, little is known about the perceptions of AAE among students in SLP programs. Method Seventy-three students from 46 randomly selected university programs in the United States completed an online survey including explicit statements regarding the validity of AAE and a matched-guide task assessing participants' implicit perceptions of AAE. Participants were randomly assigned to one of four audio pairings that differed in terms of the dialect spoken and the formality of the conversational context. Participants rated the speaker on 11 attributes (e.g., literate/illiterate, rich/poor) using the Revised Speech Dialect Attitudinal Scale. Results Participants indicated positive opinions of statements on the validity of AAE. However, across three categories of personal attributes-sociointellectual, aesthetic, and dynamism-participants who heard the Mainstream American English recordings rated the speaker differently than recordings including AAE. Conclusions Students in SLP programs express positive opinions regarding AAE, and yet, they rate speakers who speak AAE lower in personal attributes. The results highlight the importance of expanding training for future SLPs to include not only explicit statements about the value of AAE but also activities addressing implicit perceptions of dialect use. We provide a brief discussion of how the current data can be implemented for such an activity. Lesson plans and materials are provided as supplemental materials. Supplemental Material https://doi.org/10.23641/asha.15241638.


Subject(s)
Language , Speech-Language Pathology , Black or African American , Humans , Perception , Students , United States
11.
Ecology ; 102(10): e03464, 2021 10.
Article in English | MEDLINE | ID: mdl-34236709

ABSTRACT

With ongoing climate change, populations are expected to exhibit shifts in demographic performance that will alter where a species can persist. This presents unique challenges for managing plant populations and may require ongoing interventions, including in situ management or introduction into new locations. However, few studies have examined how climate change may affect plant demographic performance for a suite of species, or how effective management actions could be in mitigating climate change effects. Over the course of two experiments spanning 6 yr and four sites across a latitudinal gradient in the Pacific Northwest, United States, we manipulated temperature, precipitation, and disturbance intensity, and quantified effects on the demography of eight native annual prairie species. Each year we planted seeds and monitored germination, survival, and reproduction. We found that disturbance strongly influenced demographic performance and that seven of the eight species had increasingly poor performance with warmer conditions. Across species and sites, we observed 11% recruitment (the proportion of seeds planted that survived to reproduction) following high disturbance, but just 3.9% and 2.3% under intermediate and low disturbance, respectively. Moreover, mean seed production following high disturbance was often more than tenfold greater than under intermediate and low disturbance. Importantly, most species exhibited precipitous declines in their population growth rates (λ) under warmer-than-ambient experimental conditions and may require more frequent disturbance intervention to sustain populations. Aristida oligantha, a C4 grass, was the only species to have λ increase with warmer conditions. These results suggest that rising temperatures may cause many native annual plant species to decline, highlighting the urgency for adaptive management practices that facilitate their restoration or introduction to newly suitable locations. Frequent and intense disturbances are critical to reduce competitors and promote native annuals' persistence, but even such efforts may prove futile under future climate regimes.


Subject(s)
Climate Change , Plants , Adaptation, Physiological , Germination , Temperature
12.
Wiley Interdiscip Rev Cogn Sci ; 11(3): e1524, 2020 May.
Article in English | MEDLINE | ID: mdl-32003145

ABSTRACT

The relationship to place and language has been central to linguistic research since the beginning. Several distinctive eras of investigation into place and language have taken place, from focusing on relatively nonmobile elderly speakers to deep investigations of how different speakers relate to a particular place. Place impacts language in a variety of ways, from large differences between national varieties to ecological and social distinctions in varieties associated with a small local area or neighborhood. Further, place interacts with other social factors and contributes to linguistic variation in an additive (or perhaps even multiplicative) fashion. As the investigation into the impact of place has developed and evolved, researchers have noted that it is not merely place itself that is the most important, rather the speaker's relationship to place that is perhaps the most crucial aspect. In fact, a speaker with a close connection to place might use features that are associated with a particular place even if those features are stigmatized, because those features represent the speaker's connection to place. Without consideration of how a speaker orients-whether toward or away-any investigation into place or regionality and language will be incomplete. This article is categorized under: Linguistics > Linguistic Theory Psychology > Language.


Subject(s)
Geography , Language , Linguistics , Speech Perception , Comprehension , Female , Humans , Male , Speech
13.
Am J Disaster Med ; 15(3): 169-185, 2020.
Article in English | MEDLINE | ID: mdl-33270208

ABSTRACT

OBJECTIVE: To characterize the strengths and weaknesses of the current status of disaster research evidence; and to identify potential interventions specific to the disciplines of medicine, public health, and social sciences. DESIGN: A mixed method study using nominal group technique and a strengths, weaknesses, opportunities, and threats (SWOT) analysis. PARTICIPANTS: Subject matter experts (SMEs) in the fields of medicine, public health, and social sciences who are engaged in disaster research. RESULTS: The nominal group technique achieved 100 percent response rate. After coding and analysis, ten distinct disaster research evidence themes were identified: awareness; evidence quality; funding; human resources; interdisciplinary studies; politics; research process; research topics; sectoral collaboration; and "other." Strengths in each area were limited but focused on quality and workforce pipeline. Weaknesses were limited funding and low research quality. Opportunities included improving methods and increased interdisciplinary collaboration. The threats most consistently identified were limited funding and political influences on disaster research funding. CONCLUSIONS: Disaster research experts from three disciplines identified a number of barriers and facilitators to improving disaster-related research. The limited, inconsistent, and episodic funding and the politics related to it were the greatest and most common barriers. This weakness needs to be strategically addressed to significantly advance the field of disaster research.


Subject(s)
Disasters , Public Health , Humans , Research
14.
Am J Speech Lang Pathol ; 28(2): 599-611, 2019 05 27.
Article in English | MEDLINE | ID: mdl-31136239

ABSTRACT

Purpose Children with specific language impairment (SLI) are more likely than children with typical language (TL) to exhibit difficulties in word-level spelling accuracy. More research is needed to elucidate the contribution of linguistic knowledge to word-level spelling accuracy in this population. The purpose of this study was to explore the contributions of linguistic knowledge to spelling accuracy in a group of 2nd- to 4th-grade children with SLI and a group of 2nd- to 4th-grade children with TL. Method Participants were 32 children with SLI and 32 children with TL in Grades 2 through 4. Five areas of linguistic knowledge were assessed: phonological awareness, morphological knowledge, orthographic pattern knowledge, mental grapheme representation knowledge, and vocabulary knowledge. Mixed-effects logistic regression models were utilized to address the research aim. Results Mental grapheme representation knowledge was selected as a significant predictor in both models; however, phonological awareness was the only additional significant predictor in the model for children with SLI, whereas morphological knowledge was the only other significant predictor in the model for children with TL. Orthographic pattern knowledge and vocabulary knowledge were not significant for either group. Conclusions The results suggest that spelling instruction and intervention for children with SLI should take linguistic knowledge into account and explicitly relate linguistic knowledge to spelling. Additionally, future research should consider if instructional targets for children with SLI should differ from targets for children with TL and if these findings represent a delay or a disorder in spelling acquisition for children with SLI.


Subject(s)
Child Behavior , Child Language , Specific Language Disorder/psychology , Age Factors , Child , Female , Humans , Male , Phonetics , Reading , Semantics , Specific Language Disorder/diagnosis , Vocabulary
15.
Disaster Med Public Health Prep ; 13(3): 400-404, 2019 06.
Article in English | MEDLINE | ID: mdl-29843836

ABSTRACT

OBJECTIVE: The West African Disaster Preparedness Initiative held a disaster preparedness tabletop exercise with representatives from the Economic Community of West African States (ECOWAS) in November 2015. The tabletop exercise was hosted by the Republic of Ghana's National Disaster Management Organization and partners in Accra, Ghana. METHODS: ECOWAS Commission delegates and representatives from 10 member states were confronted with a series of simulated crises. Participants utilized existing national preparedness plans and web-based information technologies to research and communicate about internal disaster threats and those from neighboring countries. After each of the exercise's three phases, facilitators distributed participant surveys. RESULTS: A total of 106 individuals participated in the tabletop exercise. During the exercise, national teams utilizing well-developed disaster contingency plans and emergency operations center (EOC) standard operating procedures (SOPs) reached out to help less-prepared national teams. Key issues identified in the survey were language and cultural issues as barriers, effectiveness of disaster management agencies linked to heads of state, and the need for data sharing and real-time communication for situational awareness and multisector coordination. CONCLUSION: This tabletop exercise helped improve and refine the ECOWAS regional and member states' national SOPs that teams will employ to prepare for, respond to, and recover from future disasters. (Disaster Med Public Health Preparedness. 2019;13:400-404).


Subject(s)
Cost-Benefit Analysis/methods , Disaster Planning/trends , Health Services Needs and Demand/trends , Internationality , Africa, Western , Cost-Benefit Analysis/trends , Disaster Planning/methods , Humans
16.
Disaster Med Public Health Prep ; 13(2): 319-329, 2019 04.
Article in English | MEDLINE | ID: mdl-29510765

ABSTRACT

US Africa Command's Disaster Preparedness Program (DPP), implemented by the Center for Disaster and Humanitarian Assistance Medicine, partnered with US Government agencies and international organizations to promote stability and security on the African continent by engaging with African Partner Nations' (PN) civil and military authorities to improve disaster management capabilities. From 2008 to 2015, DPP conducted disaster preparedness and response programming with 17 PNs. DPP held a series of engagements with each, including workshops, strategic planning, developing preparedness and response plans, tabletop exercises, and prioritizing disaster management capability gaps identified through the engagements. DPP partners collected data for each PN to further capacity building efforts. Thus far, 9 countries have completed military pandemic plans, 10 have developed national pandemic influenza plans, 9 have developed military support to civil authorities plans, and 11 have developed disaster management strategic work plans. There have been 20 national exercises conducted since 2009. DPP was cited as key in implementation of Ebola response plans in PNs, facilitated development of disaster management agencies in DPP PNs, and trained nearly 800 individuals. DPP enhanced PNs' ability to prepare and respond to crises, fostering relationships between international agencies, and improving civil-military coordination through both national and regional capacity building. (Disaster Med Public Health Preparedness. 2019;13:319-329).


Subject(s)
Disaster Planning/organization & administration , Global Health/standards , Military Personnel/statistics & numerical data , Africa , Disaster Planning/methods , Disaster Planning/trends , Disasters/prevention & control , Global Health/statistics & numerical data , Humans , Pandemics/prevention & control , United States/ethnology
17.
Ecol Evol ; 9(6): 3637-3650, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30962915

ABSTRACT

Plant phenology will likely shift with climate change, but how temperature and/or moisture regimes will control phenological responses is not well understood. This is particularly true in Mediterranean climate ecosystems where the warmest temperatures and greatest moisture availability are seasonally asynchronous. We examined plant phenological responses at both the population and community levels to four climate treatments (control, warming, drought, and warming plus additional precipitation) embedded within three prairies across a 520 km latitudinal Mediterranean climate gradient within the Pacific Northwest, USA. At the population level, we monitored flowering and abundances in spring 2017 of eight range-restricted focal species planted both within and north of their current ranges. At the community level, we used normalized difference vegetation index (NDVI) measured from fall 2016 to summer 2018 to estimate peak live biomass, senescence, seasonal patterns, and growing season length. We found that warming exerted a stronger control than our moisture manipulations on phenology at both the population and community levels. Warming advanced flowering regardless of whether a species was within or beyond its current range. Importantly, many of our focal species had low abundances, particularly in the south, suggesting that establishment, in addition to phenological shifts, may be a strong constraint on their future viability. At the community level, warming advanced the date of peak biomass regardless of site or year. The date of senescence advanced regardless of year for the southern and central sites but only in 2018 for the northern site. Growing season length contracted due to warming at the southern and central sites (~3 weeks) but was unaffected at the northern site. Our results emphasize that future temperature changes may exert strong influence on the timing of a variety of plant phenological events, especially those events that occur when temperature is most limiting, even in seasonally water-limited Mediterranean ecosystems.

19.
J Speech Lang Hear Res ; 61(8): 2138-2145, 2018 08 08.
Article in English | MEDLINE | ID: mdl-30073278

ABSTRACT

Purpose: This study explored the extent to which hearing loss affected positive social interactions in older adults living in rural and urban communities. Method: Pure-tone behavioral hearing assessments were administered to 80 adults 60 years of age or older. In addition, all participants completed 2 questionnaires, the Medical Outcomes Study Social Support Survey (Sherbourne & Stewart, 1991) and the Patient Health Questionnaire-Ninth Edition (Kroenke, Spitzer, & Williams, 2001). Results: The preliminary findings suggested that adults with hearing loss living in rural towns had poorer positive social interactions compared with their urban counterparts with hearing loss. Also, adults with hearing loss living in rural towns had more symptoms of depression than adults with normal hearing who lived in these same geographical regions. Conclusions: These preliminary findings could indicate that older adults with hearing loss living in rural communities will face more isolation than adults with hearing loss living in urban settings. Increasing our understanding of the extent of social isolation in adults with hearing loss living in rural and urban populations will be necessary.


Subject(s)
Hearing Loss/psychology , Interpersonal Relations , Rural Population/statistics & numerical data , Social Isolation/psychology , Urban Population/statistics & numerical data , Aged , Audiometry, Pure-Tone/statistics & numerical data , Female , Humans , Male , Middle Aged , Social Support , Surveys and Questionnaires
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