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2.
Res Gerontol Nurs ; 14(5): 225-234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34542347

RESUMO

Alzheimer's disease and related dementias (ADRD) often result in communication deficits that can lead to negative health outcomes as well as complications for caregiving and clinical care. Although augmentative and alternative communication (AAC) devices have demonstrated efficacy in assisting persons living with dementia (PLWD) in communicating, few devices offer customization for the person's care preferences (e.g., clothing, food, activities) or are designed for integration into clinical care and caregiving. To address this issue, our research team is developing a novel electronic AAC prototype with a touchscreen to promote communication and personhood for PLWD. The current article describes the development of this technology and uses the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2013 Statement to describe the clinical trial that is planned to test its efficacy. TARGETS: PLWD and their care partners. INTERVENTION DESCRIPTION: Use of AAC Plus to promote communication and personhood for PLWD. MECHANISMS OF ACTION: AAC Plus will provide PLWD and care partners a way to communicate PLWD's daily preferences and provide clinical data for health care providers. OUTCOMES: Determine whether enhanced communication of daily preferences of PLWD will improve quality of life of PLWD and their care partners. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04571502 (Date of registration October 1, 2020). [Research in Gerontological Nursing, 14(5), 225-234.].


Assuntos
Demência , Informática Médica , Cuidadores , Demência/terapia , Humanos , Pessoalidade , Qualidade de Vida
3.
J Appl Gerontol ; 38(1): 73-91, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-28774215

RESUMO

Most of the 5.4 million people affected by Alzheimer's disease and other forms of dementia (AD) are noninstitutionalized, receiving care by unpaid family caregivers and medically managed by a primary care provider (PCP). Health Information Technology has been recognized for its potential in improving efficiency and quality of AD care and support for AD caregivers. Simultaneously, smartphone technologies have become an increasingly common way to deliver physical and behavioral health care. However, little is known about how smartphone technologies have been used to support AD caregiving and care. This article highlights the current need for smartphone-based interventions for AD and systematically identified and appraised current smartphone apps targeting and available for AD caregivers. Findings indicate that individual available apps have limited functions (compared with the complex needs of caregivers) and little has been done to extend AD caregiving apps to Hispanic populations. Implications for research, practice, and policy are discussed.


Assuntos
Doença de Alzheimer/terapia , Cuidadores , Aplicativos Móveis , Smartphone , Tecnologia Culturalmente Apropriada , Humanos , Qualidade da Assistência à Saúde , Autocuidado , Apoio Social
4.
J Geophys Res Earth Surf ; 121(2): 182-200, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-27134805

RESUMO

We present spatiotemporal mass balance trends for the Antarctic Ice Sheet from a statistical inversion of satellite altimetry, gravimetry, and elastic-corrected GPS data for the period 2003-2013. Our method simultaneously determines annual trends in ice dynamics, surface mass balance anomalies, and a time-invariant solution for glacio-isostatic adjustment while remaining largely independent of forward models. We establish that over the period 2003-2013, Antarctica has been losing mass at a rate of -84 ± 22 Gt yr-1, with a sustained negative mean trend of dynamic imbalance of -111 ± 13 Gt yr-1. West Antarctica is the largest contributor with -112 ± 10 Gt yr-1, mainly triggered by high thinning rates of glaciers draining into the Amundsen Sea Embayment. The Antarctic Peninsula has experienced a dramatic increase in mass loss in the last decade, with a mean rate of -28 ± 7 Gt yr-1 and significantly higher values for the most recent years following the destabilization of the Southern Antarctic Peninsula around 2010. The total mass loss is partly compensated by a significant mass gain of 56 ± 18 Gt yr-1 in East Antarctica due to a positive trend of surface mass balance anomalies.

5.
Am Nat ; 185(6): 747-55, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25996860

RESUMO

Plant resprouting after disturbance confers community resilience because individuals persist through trade-offs in resources for buds versus those required to produce seeds. However, repeated disturbance may deplete bud banks, and population persistence may become increasingly reliant on regeneration from seed. Theory predicts a shift in community assemblage from species with a strategy of persistence by resprouting (persistence niche) to one of regeneration from seed (regeneration niche) as the disturbance frequency increases. We tested, for the first time, the shifting persistence niche concept in a model system at local and regional community scales using a phylogenetically diverse floristic assemblage. Persistence traits of vascular plants were modeled as a function of dry-down frequency in wetlands. Resprouting species occupying the persistence niche were more common in stable wetlands than in those more frequently disturbed by dry downs. The patterns of resprouting species in standing vegetation and in seed banks provide strong support for the shifting persistence niche model involving trade-offs between resprouting (clonality) and sexual reproduction.


Assuntos
Ecossistema , Fenômenos Fisiológicos Vegetais , Austrália , Secas , Desenvolvimento Vegetal , Reprodução , Sementes/fisiologia , Áreas Alagadas
6.
Sci Total Environ ; 534: 31-42, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25887372

RESUMO

Postfire resprouting and recruitment from seed are key plant life-history traits that influence population dynamics, community composition and ecosystem function. Species can have one or both of these mechanisms. They confer resilience, which may determine community composition through differential species persistence after fire. To predict ecosystem level responses to changes in climate and fire conditions, we examined the proportions of these plant fire-adaptive traits among woody growth forms of 2880 taxa, in eight fire-prone ecosystems comprising ~87% of Australia's land area. Shrubs comprised 64% of the taxa. More tree (>84%) than shrub (~50%) taxa resprouted. Basal, epicormic and apical resprouting occurred in 71%, 22% and 3% of the taxa, respectively. Most rainforest taxa (91%) were basal resprouters. Many trees (59%) in frequently-burnt eucalypt forest and savanna resprouted epicormically. Although crown fire killed many mallee (62%) and heathland (48%) taxa, fire-cued seeding was common in these systems. Postfire seeding was uncommon in rainforest and in arid Acacia communities that burnt infrequently at low intensity. Resprouting was positively associated with ecosystem productivity, but resprouting type (e.g. basal or epicormic) was associated with local scale fire activity, especially fire frequency. Although rainforest trees can resprout they cannot recruit after intense fires and may decline under future fires. Semi-arid Acacia communities would be susceptible to increasing fire frequencies because they contain few postfire seeders. Ecosystems dominated by obligate seeders (mallee, heath) are also susceptible because predicted shorter inter-fire intervals will prevent seed bank accumulation. Savanna may be resilient to future fires because of the adaptive advantage of epicormic resprouting among the eucalypts. The substantial non-resprouting shrub component of shrublands may decline, but resilient Eucalyptus spp. will continue to dominate under future fire regimes. These patterns of resprouting and postfire seeding provide new insights to ecosystem assembly, resilience and vulnerability to changing fire regimes on this fire-prone continent.


Assuntos
Ecossistema , Monitoramento Ambiental , Incêndios , Austrália , Plantas , Madeira
7.
Oecologia ; 176(4): 1123-33, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25234374

RESUMO

We used a mosaic of infrequently burnt temperate rainforest and adjacent, frequently burnt eucalypt forests in temperate eastern Australia to test whether: (1) there were differences in flammability of fresh and dried foliage amongst congeners from contrasting habitats, (2) habitat flammability was related to regeneration strategy, (3) litter fuels were more flammable in frequently burnt forests, (4) the severity of a recent fire influenced the flammability of litter (as this would suggest fire feedbacks), and (5) microclimate contributed to differences in fire hazard amongst habitats. Leaf-level comparisons were made among 11 congeneric pairs from rainforest and eucalypt forests. Leaf-level ignitability, combustibility and sustainability were not consistently higher for taxa from frequently burnt eucalypt forests, nor were they higher for species with fire-driven recruitment. The bulk density of litter-bed fuels strongly influenced flammability, but eucalypt forest litter was not less dense than rainforest litter. Ignitability, combustibility and flame sustainability of community surface fuels (litter) were compared using fuel arrays with standardized fuel mass and moisture content. Forests previously burned at high fire severity did not have consistently higher litter flammability than those burned at lower severity or long unburned. Thus, contrary to the Mutch hypothesis, there was no evidence of higher flammability of litter fuels or leaves from frequently burnt eucalypt forests compared with infrequently burnt rainforests. We suggest the manifest pyrogenicity of eucalypt forests is not due to natural selection for more flammable foliage, but better explained by differences in crown openness and associated microclimatic differences.


Assuntos
Clima , Eucalyptus , Incêndios , Florestas , Folhas de Planta , Seleção Genética , Árvores , Austrália , Ecossistema , Floresta Úmida
8.
Oecologia ; 175(1): 261-71, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24469341

RESUMO

A popular hypothesis for tree and grass coexistence in savannas is that tree seedlings are limited by competition from grasses. However, competition may be important in favourable climatic conditions when abiotic stress is low, whereas facilitation may be more important under stressful conditions. Seasonal and inter-annual fluctuations in abiotic conditions may alter the outcome of tree-grass interactions in savanna systems and contribute to coexistence. We investigated interactions between coolibah (Eucalyptus coolabah) tree seedlings and perennial C4 grasses in semi-arid savannas in eastern Australia in contrasting seasonal conditions. In glasshouse and field experiments, we measured survival and growth of tree seedlings with different densities of C4 grasses across seasons. In warm glasshouse conditions, where water was not limiting, competition from grasses reduced tree seedling growth but did not affect tree survival. In the field, all tree seedlings died in hot dry summer conditions irrespective of grass or shade cover, whereas in winter, facilitation from grasses significantly increased tree seedling survival by ameliorating heat stress and protecting seedlings from herbivory. We demonstrated that interactions between tree seedlings and perennial grasses vary seasonally, and timing of tree germination may determine the importance of facilitation or competition in structuring savanna vegetation because of fluctuations in abiotic stress. Our finding that trees can grow and survive in a dense C4 grass sward contrasts with the common perception that grass competition limits woody plant recruitment in savannas.


Assuntos
Ecossistema , Eucalyptus/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Estações do Ano , Austrália , Plântula/crescimento & desenvolvimento , Temperatura , Árvores/crescimento & desenvolvimento , Água
10.
Oecologia ; 162(3): 719-32, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19859742

RESUMO

Predicting changes in vegetation structure in fire-prone arid/semi-arid systems is fraught with uncertainty because the limiting factors to coexistence between grasses and woody plants are unknown. We investigated abiotic and biotic factors influencing boundaries and habitat membership in grassland (Triodia or 'spinifex' grassland)-shrubland (Acacia aneura or 'mulga' shrubland) mosaics in semi-arid central Australia. We used a field experiment to test for the effects of: (1) topographic relief (dune/swale habitat), (2) adult neighbour removal, and (3) soil type (sand/clay) on seedling survival in three shrub and two grass species in reciprocal field plantings. Our results showed that invasion of the shrubland (swale) by neighbouring grassland species is negated by abiotic limitations but competition limits shrubland invasion of the grassland (dune). All species from both habitats had significantly reduced survival in the grassland (dune) in the presence of the dominant grass (Triodia) regardless of soil type or shade. Further, the removal of the dominant grass allowed the shrubland dominant (A. aneura) to establish outside its usual range. Seedling growth and sexual maturation of the shrubland dominant (A. aneura) was slow, implying that repeated fire creates an immaturity risk for this non-sprouter in flammable grassland. By contrast, rapid growth and seed set in the grassland shrubs (facultative sprouters) provides a solution to fire exposure prior to reproductive onset. In terms of landscape dynamics, we argue that grass competition and fire effects are important constraints on shrubland patch expansion, but that their relative importance will vary spatially throughout the landscape because of spatial and temporal rainfall variability.


Assuntos
Poaceae , Madeira , Austrália , Incêndios
11.
Ecology ; 89(7): 1850-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18705372

RESUMO

Trade-offs in allocation to resprouting vs. seedling regeneration in plants are predicted to occur along fire disturbance gradients. Increased resprouting ability should be generally favored in plant communities with a high probability of crown fire return. Hence, communities dominated by resprouters are predicted to have smaller seed banks than those dominated by species killed by fire. We tested whether there were trait shifts in resprouting ability among growth forms (short-lived herbaceous vs. ground-dwelling perennials vs. shrubs) and among communities (rocky outcrop vs. sclerophyll forest) with contrasting probabilities of crown fire return. Resprouting was more common in ground-dwelling perennials and in the sclerophyll forest community with a high probability of crown fire. Soil seed banks were sampled in rocky outcrop and sclerophyll forest communities in recently burned (18 months) and long-since-burned (12 years) locations at interspersed replicated sites. Collected seed banks were treated with orthogonal treatments of fire stimuli or no stimuli, and seedling emergence was measured in controlled conditions. Seed bank composition reflected the pattern of extant vegetation, with resprouting species being more common in the community with a higher probability of crown fire. Overall, however, resprouting species were poorly represented in the seed bank compared to those species killed by fire. Predicted shifts in allocation to seed production were strongly manifested in community seed banks across the disturbance gradient. Fewer species, seedlings, and seedlings per adult emerged from seed banks in the sclerophyll forest. This suggests that the dominance of resprouting species influences recruitment at the community scale. Community patterns in the seed bank also reflected predicted trade-offs with plant size and growth rate. Short-lived species that are killed by fire dominated the seed bank on rocky outcrops, while longer-lived resprouting species were found in low abundance. Life history trade-offs in persistence and regeneration strongly contribute to coexistence patterns between and within communities with contrasting probabilities of fire return.


Assuntos
Ecossistema , Desenvolvimento Vegetal , Sementes/fisiologia , Austrália , Incêndios , Germinação/fisiologia
12.
Dev Biol ; 246(1): 86-102, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12027436

RESUMO

The investigation and modeling of gene regulatory networks requires computational tools specific to the task. We present several locally developed software tools that have been used in support of our ongoing research into the embryogenesis of the sea urchin. These tools are especially well suited to iterative refinement of models through experimental and computational investigation. They include: BioArray, a macroarray spot processing program; SUGAR, a system to display and correlate large-BAC sequence analyses; SeqComp and FamilyRelations, programs for comparative sequence analysis; and NetBuilder, an environment for creating and analyzing models of gene networks. We also present an overview of the process used to build our model of the Strongylocentrotus purpuratus endomesoderm gene network. Several of the tools discussed in this paper are still in active development and some are available as open source.


Assuntos
Biologia Computacional , Genes Reguladores , Cromossomos Artificiais Bacterianos , DNA Complementar , Hibridização de Ácido Nucleico
13.
Dev Biol ; 246(1): 148-61, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12027440

RESUMO

We demonstrate that interspecific sequence conservation can provide a systematic guide to the identification of functional cis-regulatory elements within a large expanse of genomic DNA. The test was carried out on the otx gene of Strongylocentrotus purpuratus. This gene plays a major role in the gene regulatory network that underlies endomesoderm specification in the embryo. The cis-regulatory organization of the otx gene is expected to be complex, because the gene has three different start sites (X. Li, C.-K. Chuang, C.-A. Mao, L. M. Angerer, and W. H. Klein, 1997, Dev. Biol. 187, 253-266), and it is expressed in many different spatial domains of the embryo. BAC recombinants containing the otx gene were isolated from Strongylocentrotus purpuratus and Lytechinus variegatus libraries, and the ordered sequence of these BACs was obtained and annotated. Sixty kilobases of DNA flanking the gene, and included in the BAC sequence from both species, were scanned computationally for short conserved sequence elements. For this purpose, we used a newly constructed software package assembled in our laboratory, "FamilyRelations." This tool allows detection of sequence similarities above a chosen criterion within sliding windows set at 20-50 bp. Seventeen partially conserved regions, most a few hundred base pairs long, were amplified from the S. purpuratus BAC DNA by PCR, inserted in an expression vector driving a CAT reporter, and tested for cis-regulatory activity by injection into fertilized S. purpuratus eggs. The regulatory activity of these constructs was assessed by whole-mount in situ hybridization (WMISH) using a probe against CAT mRNA. Of the 17 constructs, 11 constructs displayed spatially restricted regulatory activity, and 6 were inactive in this test. The domains within which the cis-regulatory constructs were expressed are approximately consistent with results from a WMISH study on otx expression in the embryo, in which we used probes specific for the mRNAs generated from each of the three transcription start sites. Four separate cis-regulatory elements that specifically produce endomesodermal expression were identified, as well as ubiquitously active elements, and ectoderm-specific elements. We confirm predictions from other work with respect to target sites for specific transcription factors within the elements that express in the endoderm.


Assuntos
Sequências Reguladoras de Ácido Nucleico , Ouriços-do-Mar/embriologia , Animais , Cromossomos Artificiais Bacterianos , DNA , Vetores Genéticos , Hibridização In Situ , Ouriços-do-Mar/genética , Especificidade da Espécie
14.
Dev Biol ; 246(1): 162-90, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12027441

RESUMO

We present the current form of a provisional DNA sequence-based regulatory gene network that explains in outline how endomesodermal specification in the sea urchin embryo is controlled. The model of the network is in a continuous process of revision and growth as new genes are added and new experimental results become available; see http://www.its.caltech.edu/~mirsky/endomeso.htm (End-mes Gene Network Update) for the latest version. The network contains over 40 genes at present, many newly uncovered in the course of this work, and most encoding DNA-binding transcriptional regulatory factors. The architecture of the network was approached initially by construction of a logic model that integrated the extensive experimental evidence now available on endomesoderm specification. The internal linkages between genes in the network have been determined functionally, by measurement of the effects of regulatory perturbations on the expression of all relevant genes in the network. Five kinds of perturbation have been applied: (1) use of morpholino antisense oligonucleotides targeted to many of the key regulatory genes in the network; (2) transformation of other regulatory factors into dominant repressors by construction of Engrailed repressor domain fusions; (3) ectopic expression of given regulatory factors, from genetic expression constructs and from injected mRNAs; (4) blockade of the beta-catenin/Tcf pathway by introduction of mRNA encoding the intracellular domain of cadherin; and (5) blockade of the Notch signaling pathway by introduction of mRNA encoding the extracellular domain of the Notch receptor. The network model predicts the cis-regulatory inputs that link each gene into the network. Therefore, its architecture is testable by cis-regulatory analysis. Strongylocentrotus purpuratus and Lytechinus variegatus genomic BAC recombinants that include a large number of the genes in the network have been sequenced and annotated. Tests of the cis-regulatory predictions of the model are greatly facilitated by interspecific computational sequence comparison, which affords a rapid identification of likely cis-regulatory elements in advance of experimental analysis. The network specifies genomically encoded regulatory processes between early cleavage and gastrula stages. These control the specification of the micromere lineage and of the initial veg(2) endomesodermal domain; the blastula-stage separation of the central veg(2) mesodermal domain (i.e., the secondary mesenchyme progenitor field) from the peripheral veg(2) endodermal domain; the stabilization of specification state within these domains; and activation of some downstream differentiation genes. Each of the temporal-spatial phases of specification is represented in a subelement of the network model, that treats regulatory events within the relevant embryonic nuclei at particular stages.


Assuntos
Endoderma , Genes Reguladores , Mesoderma , Ouriços-do-Mar/embriologia , Animais , Modelos Biológicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
Science ; 295(5560): 1669-78, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11872831

RESUMO

Development of the body plan is controlled by large networks of regulatory genes. A gene regulatory network that controls the specification of endoderm and mesoderm in the sea urchin embryo is summarized here. The network was derived from large-scale perturbation analyses, in combination with computational methodologies, genomic data, cis-regulatory analysis, and molecular embryology. The network contains over 40 genes at present, and each node can be directly verified at the DNA sequence level by cis-regulatory analysis. Its architecture reveals specific and general aspects of development, such as how given cells generate their ordained fates in the embryo and why the process moves inexorably forward in developmental time.


Assuntos
Endoderma/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Mesoderma/fisiologia , Ouriços-do-Mar/embriologia , Ouriços-do-Mar/genética , Animais , Linhagem da Célula , Biologia Computacional , Desenvolvimento Embrionário , Endoderma/citologia , Perfilação da Expressão Gênica , Genes Reguladores , Mesoderma/citologia , Modelos Biológicos , Modelos Genéticos , Morfogênese , Sequências Reguladoras de Ácido Nucleico , Células-Tronco/fisiologia , Teoria de Sistemas
16.
Oecologia ; 132(4): 582-591, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28547645

RESUMO

Rock outcrops are landscape features that may form habitat islands in a matrix of more widespread vegetation. The patterns of floristics, reproduction, gender, life span, growth forms, and fire response traits were compared between rock outcrops and matrix sclerophyll vegetation to test for insularity in taxon composition and functional traits. The outcrops and matrix had similar reproduction, gender, life span, and growth form traits, being dominated by co-sexual sclerophyll shrubs. The outcrops, however, were dissimilar in species composition and functional traits forming an archipelago of habitat islands in a forest matrix. Rank abundance curves were less even on rock outcrops than in adjacent forests, being dominated by shrubs that were killed by fire (obligate seeders). The ratio of shrubs killed by fire (obligate seeders) to resprouters was 70:30 on the outcrops compared with 38:62 in the matrix. Evidence for functional convergence in fire response traits comes from 27 genera, in 17 families, which have congeners in each habitat. Most shrub congeners on or near rocky outcrops were killed by fire whereas related taxa in the forests resprout after fire. Functional convergence can be related to disturbance frequency and/or differences in regeneration niche among habitats. A resprouting response appears to be related to more frequent fires in the matrix as outcrops experience fires less often. The dominance of obligate seeding shrubs on high rainfall outcrops may also be related to better resources in an environment where allocation to growth rather than storage could be advantageous. In drier and shadier habitats, however, resprouting may be promoted over seedling recruitment as the risks of recruitment failure are higher.

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