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1.
Mol Phylogenet Evol ; 100: 183-198, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26988413

RESUMO

The bee tribe Anthidiini (Hymenoptera: Megachilidae) is a large, cosmopolitan group of solitary bees that exhibit intriguing nesting behavior. We present the first molecular-based phylogenetic analysis of relationships within Anthidiini using model-based methods and a large, multi-locus dataset (five nuclear genes, 5081 base pairs), as well as a combined analysis using our molecular dataset in conjunction with a previously published morphological matrix. We discuss the evolution of nesting behavior in Anthidiini and the relationship between nesting material and female mandibular morphology. Following an examination of the morphological characters historically used to recognize anthidiine genera, we recommend the use of a molecular-based phylogenetic backbone to define taxonomic groups prior to the assignment of diagnostic morphological characters for these groups. Finally, our results reveal the paraphyly of numerous genera and have significant consequences for anthidiine classification. In order to promote a classification system based on stable, monophyletic clades, we hereby make the following changes to Michener's (2007) classification: The subgenera Afranthidium (Zosteranthidium) Michener and Griswold, 1994, Afranthidium (Branthidium) Pasteels, 1969 and Afranthidium (Immanthidium) Pasteels, 1969 are moved into the genus Pseudoanthidium, thus forming the new combinations Pseudoanthidium (Zosteranthidium), Pseudoanthidium (Branthidium), and Pseudoanthidium (Immanthidium). The genus Neanthidium Pasteels, 1969 is also moved into the genus Pseudoanthidium, thus forming the new combination Pseudoanthidium (Neanthidium). Based on morphological characters shared with our new definition of the genus Pseudoanthidium, the subgenus Afranthidium (Mesanthidiellum) Pasteels, 1969 and the genus Gnathanthidium Pasteels, 1969 are also moved into the genus Pseudoanthidium, thus forming the new combinations Pseudoanthidium (Mesanthidiellum) and Pseudoanthidium (Gnathanthidium).


Assuntos
Abelhas/classificação , Animais , Abelhas/genética , Evolução Biológica , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Feminino , Mandíbula/anatomia & histologia , Comportamento de Nidação/fisiologia , Filogenia , Análise de Sequência de DNA
2.
Phys Chem Chem Phys ; 17(39): 25761-71, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25792194

RESUMO

We report on a new instrument that allows for the investigation of weakly-bound molecular aggregates under equilibrium conditions (constant temperature and pressure). The aggregates are formed in a Laval nozzle and probed with time-of-flight mass spectrometry in the uniform postnozzle flow; i.e. in the equilibrium region of the flow. Aggregates over a very broad size range from the monomer to particle sizes of 10-20 nm can be generated and studied with this setup. Soft ionization of the aggregates is performed with single photons from a homemade vacuum ultraviolet laser. The mass spectrometric detection provides molecular-level information on the size and chemical composition of the aggregates. This new instrument is useful for a broad range of cluster studies that require well-defined conditions.

3.
Phys Chem Chem Phys ; 15(3): 940-9, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23201898

RESUMO

The fragmentation of methanol, water, dimethyl ether, and acetic acid clusters upon photoionization with a single vacuum ultraviolet (VUV) photon of 10.1 eV, 13.3 eV, or 17.5 eV energy is studied with mass spectrometry. The sodium-doping method is used as an independent approximate measure of the original cluster size distribution providing information on the degree of fragmentation upon VUV ionization. The experimental results show strong fragmentation for (CH(3))(2)O and CH(3)CO(2)H clusters but minor fragmentation for H(2)O and CH(3)OH clusters. The pronounced cluster decay for (CH(3))(2)O and CH(3)CO(2)H is explained by additional intracluster chain reactions that occur after the initial fast proton transfer in the ionic clusters, i.e. the decay of (CH(3))(2)O molecules into H(2), CO, and CH(4) catalyzed by the methoxymethyl radical, and the decay of CH(3)CO(2)H molecules into CO(2) and CH(4) catalyzed by the acetyloxy radical. The absence of equivalent reaction cycles in ionic H(2)O and CH(3)OH clusters after the fast proton transfer is consistent with the much less pronounced cluster fragmentation observed upon VUV ionization. The study shows that VUV photoionization even at threshold cannot in general be considered a soft ionization method for weakly-bound clusters, largely because of potential intracluster reaction.

4.
J Am Geriatr Soc ; 71(11): 3424-3434, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37539948

RESUMO

BACKGROUND: Care management programs are widely used to improve care coordination and management of chronic conditions for high-need older adults. With many care management programs targeting a small number of people, high-need older adults may receive services from more than one care management program (co-occurring care management), the implications of which are unknown. METHODS: We conducted semi-structured interviews with 37 care managers, 15 older adults, and 13 caregivers, who were recruited through an urban academic medical center and a large rural health system in Maryland. We analyzed interview transcripts using qualitative content analysis with the aim of understanding contributors to, implications of, and strategies to manage co-occurring care management among high-need older adults. RESULTS: Contributors to co-occurring care management included siloed programs due to program-specific financial incentives and inability to easily identify other involved care managers, and the complex needs of the enrolled older adult population, which motivated involvement of more than one program. Implications of co-occurring care management included older adults and caregivers feeling cared for and safe when they had multiple care management programs involved and reporting value in their relationships with care managers. Older adults were identified as having greater access to resources and improved care when care manager roles were aligned in a complementary way; however, misaligned roles posed the potential for confusion about care manager accountability for tasks and resulted in frustration and lack of follow-through. Strategies for managing co-occurring care management included alignment of care manager roles through communication and negotiation and older adults and caregivers identifying and relying on a single care manager with whom they had the strongest relationship. CONCLUSIONS: Initiatives that clarify strengthen the relationship between care managers and older adults, increase care manager visibility, and facilitate communication across care managers may help foster collaboration.


Assuntos
Cuidadores , Humanos , Idoso , Doença Crônica , Maryland
5.
Proc Biol Sci ; 278(1724): 3593-600, 2011 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21490010

RESUMO

Stark contrasts in clade species diversity are reported across the tree of life and are especially conspicuous when observed in closely related lineages. The explanation for such disparity has often been attributed to the evolution of key innovations that facilitate colonization of new ecological niches. The factors underlying diversification in bees remain poorly explored. Bees are thought to have originated from apoid wasps during the Mid-Cretaceous, a period that coincides with the appearance of angiosperm eudicot pollen grains in the fossil record. The reliance of bees on angiosperm pollen and their fundamental role as angiosperm pollinators have contributed to the idea that both groups may have undergone simultaneous radiations. We demonstrate that one key innovation--the inclusion of foreign material in nest construction--underlies both a massive range expansion and a significant increase in the rate of diversification within the second largest bee family, Megachilidae. Basal clades within the family are restricted to deserts and exhibit plesiomorphic features rarely observed among modern bees, but prevalent among apoid wasps. Our results suggest that early bees inherited a suite of behavioural traits that acted as powerful evolutionary constraints. While the transition to pollen as a larval food source opened an enormous ecological niche for the early bees, the exploitation of this niche and the subsequent diversification of bees only became possible after bees had evolved adaptations to overcome these constraints.


Assuntos
Abelhas/genética , Evolução Biológica , Animais , Abelhas/fisiologia , Comportamento Alimentar , Genes de Insetos , Magnoliopsida , Dados de Sequência Molecular , Comportamento de Nidação , Filogenia , Pólen , Análise de Sequência de DNA
6.
Mol Phylogenet Evol ; 60(3): 295-304, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21600997

RESUMO

The placement of the root node in a phylogeny is fundamental to characterizing evolutionary relationships. The root node of bee phylogeny remains unclear despite considerable previous attention. In order to test alternative hypotheses for the location of the root node in bees, we used the F1 and F2 paralogs of elongation factor 1-alpha (EF-1α) to compare the tree topologies that result when using outgroup versus paralogous rooting. Fifty-two taxa representing each of the seven bee families were sequenced for both copies of EF-1α. Two datasets were analyzed. In the first (the "concatenated" dataset), the F1 and F2 copies for each species were concatenated and the tree was rooted using appropriate outgroups (sphecid and crabronid wasps). In the second dataset (the "duplicated" dataset), the F1 and F2 copies were aligned to each another and each copy for all taxa were treated as separate terminals. In this dataset, the root was placed between the F1 and F2 copies (e.g., paralog rooting). Bayesian analyses demonstrate that the outgroup rooting approach outperforms paralog rooting, recovering deeper clades and showing stronger support for groups well established by both morphological and other molecular data. Sequence characteristics of the two copies were compared at the amino acid level, but little evidence was found to suggest that one copy is more functionally conserved. Although neither approach yields an unambiguous root to the tree, both approaches strongly indicate that the root of bee phylogeny does not fall near Colletidae, as has been previously proposed. We discuss paralog rooting as a general strategy and why this approach performs relatively poorly with our particular dataset.


Assuntos
Abelhas/classificação , Duplicação Gênica , Filogenia , Animais , Teorema de Bayes , Abelhas/genética , Evolução Molecular , Modelos Genéticos , Fator 1 de Elongação de Peptídeos/genética , Análise de Sequência de DNA/métodos
7.
Popul Health Manag ; 24(3): 338-344, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32758066

RESUMO

Care management programs that facilitate collaboration between care managers and primary care clinicians are more likely to be successful in improving chronic disease metrics than programs that do not facilitate such collaboration. The authors sought to understand care managers' perspectives on interacting with primary care clinicians. Semi-structured qualitative interviews were conducted with care managers (n = 29) from 3 health systems in and around a large, urban academic center. Interviews were audio recorded, transcribed verbatim, and iteratively analyzed using a grounded theory approach. Care managers worked for health plans (14%), outpatient specialty clinics (31%), hospitals and emergency departments (24%), and primary care offices (14%). Care managers identified the primary care clinician as leading patients' care and as essential to avoiding unnecessary utilization. Care managers described variability in and barriers to interacting with primary care clinicians. When possible, care managers use the electronic medical record to facilitate interaction rather than communicating directly (eg, phone call) with primary care clinicians. The role of the care manager varied across programs, contributing to primary care clinicians' poor understanding of what the care manager could provide. Consequently, primary care clinicians asked the care manager for help with tasks beyond his/her role. Care managers felt inferior to primary care clinicians, a potential result of the traditional medical hierarchy, which also hindered interactions. Although care managers view interactions with the primary care clinician as essential to the health of the patient, communication challenges, variability of the care manager's role, and medical hierarchy limit collaboration.


Assuntos
Assistência ao Paciente , Atenção Primária à Saúde , Instituições de Assistência Ambulatorial , Feminino , Humanos , Masculino , Pesquisa Qualitativa
8.
Sensors (Basel) ; 10(3): 1716-42, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22294895

RESUMO

Waveguide-based cavity ring-down spectroscopy (CRD) can be used for quantitative measurements of chemical concentrations in small amounts of liquid, in gases or in films. The change in ring-down time can be correlated to analyte concentration when using fiber optic sensing elements that change their attenuation in dependence of either sample absorption or refractive index. Two types of fiber cavities, i.e., fiber loops and fiber strands containing reflective elements, are distinguished. Both types of cavities were coupled to a variety of chemical sensor elements, which are discussed and compared.


Assuntos
Tecnologia de Fibra Óptica , Análise Espectral , Eletroforese Capilar , Técnicas Analíticas Microfluídicas , Refratometria
9.
J Phys Chem A ; 113(16): 3963-72, 2009 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-19249854

RESUMO

Optical feedback cavity ring-down spectroscopy (OF-CRDS) using a continuous wave distributed feedback diode laser at 1650 nm has been used to measure extinction of light by samples of monodisperse spherical aerosol particles <1 mum in diameter. The OF-CRDS method allows measurements of low levels of extinction of incident light to be made at repetition rates of 1 kHz or greater. A statistical model is proposed to describe the linear relationship between the extinction coefficient (alpha) and its variance (Var(alpha)). Application of this model to experimental measurements of Var(alpha) for a range of alpha values typically below approximately 1 x 10(-6) cm(-1) allows extinction cross-sections for the aerosol particles to be obtained without need for knowledge of the particle number density. Samples of polystyrene spheres with diameters of 400, 500, 600, and 700 nm were used to test the model by comparing extinction cross-sections determined from the experiment with the predictions of Mie theory calculations. Fitting of ring-down decay traces exhibiting amplitude noise to extract cavity ring-down times introduces additional quadratic and higher order polynomial dependencies of the variance that become significant for larger particle number densities and thus extinction coefficients (typically for alpha > 1 x 10(-6) cm(-1) under our experimental conditions). Aggregation of particles at larger number densities is suggested as a further source of variance in the measurements. Extinction cross-sections are severely underestimated if the measurements are made too rapidly to sample uncorrelated distributions of particle numbers and positions.


Assuntos
Aerossóis/química , Fenômenos Ópticos , Análise de Variância , Simulação por Computador , Modelos Moleculares , Tamanho da Partícula , Poliestirenos/química , Reprodutibilidade dos Testes , Análise Espectral
10.
Philos Trans R Soc Lond B Biol Sci ; 374(1769): 20180196, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30967087

RESUMO

Brood parasitism is a specialized form of parasitism in which the offspring of a parasite develops on the food provisions gathered by a host species for its own young. Obligate brood parasitic lineages have lost the ability to acquire provisions for their young and thus rely entirely on the location of an appropriate host to serve as a food-provider. Solitary bees provide some of the most fascinating examples of brood parasitism in animals. Most solitary bees build and provision their own nests. Some, however, usurp the nests of other species of bees. These brood parasites, or 'cuckoo' bees, deposit their eggs on the pollen provisions collected by a host bee for her own offspring. The provisions stored by the host bee are not sufficient to sustain the development of both the host's larva and that of the brood parasite and the parasite must kill the offspring of its host in order to obtain enough nourishment to complete its development. As a consequence, there is fierce competition between the host bee seeking to protect her nest from attack and the brood parasite seeking to avoid detection by the host in order to successfully deposit her eggs in an appropriate nest. In this paper, I review the behaviours that allow brood parasitic bees to escape detection by their hosts. Identifying these behaviours, and placing them within the general context of strategies employed by brood parasitic bees to parasitize the nests of their hosts, is key to understanding how brood parasitic lineages may have evolved from nest-building ancestors, decrypting the selective pressures that drive evolutionary transitions from one strategy to another and, more broadly, revealing how similar selective pressures in widely divergent lineages of animals have given rise to remarkably convergent behaviours. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.


Assuntos
Abelhas/fisiologia , Abelhas/parasitologia , Interações Hospedeiro-Parasita , Comportamento de Nidação , Animais , Evolução Biológica , Feminino
11.
PLoS One ; 13(12): e0208639, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30576327

RESUMO

Butterfly monitoring and Red List programs in Switzerland rely on a combination of observations and collection records to document changes in species distributions through time. While most butterflies can be identified using morphology, some taxa remain challenging, making it difficult to accurately map their distributions and develop appropriate conservation measures. In this paper, we explore the use of the DNA barcode (a fragment of the mitochondrial gene COI) as a tool for the identification of Swiss butterflies and forester moths (Rhopalocera and Zygaenidae). We present a national DNA barcode reference library including 868 sequences representing 217 out of 224 resident species, or 96.9% of Swiss fauna. DNA barcodes were diagnostic for nearly 90% of Swiss species. The remaining 10% represent cases of para- and polyphyly likely involving introgression or incomplete lineage sorting among closely related taxa. We demonstrate that integrative taxonomic methods incorporating a combination of morphological and genetic techniques result in a rate of species identification of over 96% in females and over 98% in males, higher than either morphology or DNA barcodes alone. We explore the use of the DNA barcode for exploring boundaries among taxa, understanding the geographical distribution of cryptic diversity and evaluating the status of purportedly endemic taxa. Finally, we discuss how DNA barcodes may be used to improve field practices and ultimately enhance conservation strategies.


Assuntos
Borboletas/genética , Código de Barras de DNA Taxonômico , Mariposas/genética , Animais , Borboletas/classificação , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Biblioteca Gênica , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Masculino , Mariposas/classificação , Suíça
12.
Acad Pediatr ; 17(2): 184-190, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28259340

RESUMO

BACKGROUND: Children and adolescents necessitating hospitalization for physical health conditions are at high risk for mental health conditions; however, the prevalence of mental health conditions and symptoms among hospitalized children and adolescents is uncertain. The objective of this study was to determine the proportion of hospitalized children and adolescents who have diagnosed mental health disorders or undiagnosed mental health problems. METHODS: In this single-center point prevalence study of hospitalized children between the ages of 4 and 21 years, patients or their parents reported known mental health diagnoses and use of services using the Services Assessment for Children and Adolescent, and they reported patient mental health symptoms using the Pediatric Symptom Checklist, 17-item form (PSC-17). RESULTS: Of 229 eligible patients, 119 agreed to participate. Demographic characteristics of patients who enrolled were not statistically significantly different from those of patients who declined to participate. Among participants, 26% (95% confidence interval [CI], 18%-35%) reported a known mental health diagnosis. On the PSC-17, 29% (95% CI, 21%-38%) of participants had a positive screen for mental health symptoms. Of those with a positive screen, 38% (95% CI, 21%-55%) had no known mental health diagnosis, and 26% (95% CI, 12%-43%) had not received ambulatory mental health services in the 12 months before hospitalization. CONCLUSIONS: Mental health conditions and symptoms are common among patients hospitalized in a tertiary children's hospital, and many affected patients are not receiving ambulatory mental health services.


Assuntos
Hospitalização , Transtornos Mentais/epidemiologia , Adolescente , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/epidemiologia , Ansiedade/psicologia , Transtornos de Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/epidemiologia , Transtorno Autístico/psicologia , Criança , Pré-Escolar , Depressão/tratamento farmacológico , Depressão/epidemiologia , Depressão/psicologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Feminino , Hospitais Pediátricos , Humanos , Masculino , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/psicologia , Saúde Mental , Serviços de Saúde Mental/estatística & dados numéricos , Philadelphia/epidemiologia , Prevalência , Adulto Jovem
13.
Evolution ; 67(10): 2982-98, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24094348

RESUMO

The evolution of parasitic behavior may catalyze the exploitation of new ecological niches yet also binds the fate of a parasite to that of its host. It is thus not clear whether evolutionary transitions from free-living organism to parasite lead to increased or decreased rates of diversification. We explore the evolution of brood parasitism in long-tongued bees and find decreased rates of diversification in eight of 10 brood parasitic clades. We propose a pathway for the evolution of brood parasitic strategy and find that a strategy in which a closed host nest cell is parasitized and the host offspring is killed by the adult parasite represents an obligate first step in the appearance of a brood parasitic lineage; this ultimately evolves into a strategy in which an open host cell is parasitized and the host offspring is killed by a specialized larval instar. The transition to parasitizing open nest cells expanded the range of potential hosts for brood parasitic bees and played a fundamental role in the patterns of diversification seen in brood parasitic clades. We address the prevalence of brood parasitic lineages in certain families of bees and examine the evolution of brood parasitism in other groups of organisms.


Assuntos
Abelhas/genética , Biodiversidade , Evolução Biológica , Comportamento de Nidação/fisiologia , Parasitos/genética , Animais , Teorema de Bayes , Abelhas/fisiologia , Modelos Genéticos , Parasitos/fisiologia , Filogenia , Especificidade da Espécie
14.
Biomed Mater ; 3(2): 025015, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18523340

RESUMO

Experimentally, porcine bladder acellular matrix (ACM) that mimics extracellular matrix has excellent potential as a bladder substitute. Herein we investigated the spatial localization and expression of different key cellular and extracellular proteins in the ACM; furthermore, we evaluated the inherent mechanical properties of the resultant ACM prior to implantation. Using a proprietary decellularization method, the DNA contents in both ACM and normal bladder were measured; in addition we used immunohistochemistry and western blots to quantify and localize the different cellular and extracellular components, and finally the mechanical testing was performed using a uniaxial mechanical testing machine. The mean DNA content in the ACM was significantly lower in the ACM compared to the bladder. Furthermore, the immunohistochemical and western blot analyses showed that collagen I and IV were preserved in the ACM, but possibly denatured collagen III in the ACM. Furthermore, elastin, laminin and fibronectin were mildly reduced in the ACM. Although the ACM did not exhibit nucleated cells, residual cellular components (actin, myosin, vimentin and others) were still present. There was, on the other hand, no significant difference in the mean stiffness between the ACM and the bladder. Although our decellularization method is effective in removing nuclear material from the bladder while maintaining its inherent mechanical properties, further work is mandatory to determine whether these residual DNA and cellular remnants would lead to any immune reaction, or if the mechanical properties of the ACM are preserved upon implantation and cellularization.


Assuntos
Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Fracionamento Celular/métodos , Proteínas da Matriz Extracelular/química , Matriz Extracelular/química , Engenharia Tecidual/métodos , Bexiga Urinária/química , Animais , Sistema Livre de Células , Elasticidade , Teste de Materiais , Estresse Mecânico , Suínos , Resistência à Tração
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