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1.
South Med J ; 117(5): 272-278, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38701849

RESUMO

OBJECTIVES: Organizations recommend providing confidential adolescent health care to reduce the consequences of high-risk health behaviors such as substance use, unhealthy eating patterns, and high-risk sexual behaviors. Family physicians are uniquely positioned to provide confidential counseling and care to this vulnerable population but must be trained to provide such care. This study describes the impact of formal and informal training on the knowledge of and comfort level in providing confidential adolescent healthcare among a sample of US Family Medicine residents. METHODS: Electronic surveys were distributed to all Family Medicine residents throughout the United States. We used descriptive statistics and χ2 analysis where appropriate to determine the association between resident-reported receipt of training, confidence, and frequency in providing confidential adolescent health care. RESULTS: A total of 714 Family Medicine residents completed the survey. The majority reported no formal training in residency (50.3%). The receipt of formal and informal training in both medical school and residency was associated with a greater degree of comfort in providing confidential adolescent care and a higher likelihood of providing confidential time alone. Those reporting formal training were more likely to always provide confidential care (P = 0.001). CONCLUSIONS: Training focused on confidential adolescent health care in medical school or residency was associated with a greater degree of comfort and a higher likelihood of providing confidential adolescent health care.


Assuntos
Confidencialidade , Medicina de Família e Comunidade , Internato e Residência , Humanos , Internato e Residência/estatística & dados numéricos , Estados Unidos , Feminino , Medicina de Família e Comunidade/educação , Masculino , Adolescente , Adulto , Inquéritos e Questionários , Serviços de Saúde do Adolescente/estatística & dados numéricos , Competência Clínica/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde
2.
PLoS One ; 18(4): e0283846, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37018290

RESUMO

BACKGROUND: Globally, almost 15 million infants are born prematurely each year, disproportionately affecting low and middle-income countries. In the absence of mother's milk, the World Health Organization recommends using donor human milk (DHM) due to its protective effect against necrotizing enterocolitis, a life-threatening intestinal disorder. The use of DHM is increasing globally, with many low and middle-income countries integrating donor milk banks into their public health strategies to reduce neonatal mortality, yet very little is known about the nutritional composition of DHM. Additional knowledge gaps include how DHM composition is influenced by milk banking practices, and whether preterm nutrient recommendations are achieved when DHM is used with commercially available fortifiers. METHODS: We designed a multi-site study with eight geographically diverse milk bank partners in high, middle, and low-income settings that will examine and compare a broad range of nutrients and bioactive factors in human milk from 600 approved milk bank donors around the world to create comprehensive, geographically diverse nutrient profiles for DHM. We will then simulate the random pooling of 2 to 10 donors to evaluate the impact of pooling as a potential strategy for milk banks to manage nutrient variability in DHM. Finally, we will evaluate whether commercially available fortifiers meet nutrient recommendations when used with DHM. DISCUSSION: We expect that results from this study will improve nutritional care globally for the growing number of preterm infants who receive donor human milk.


Assuntos
Bancos de Leite Humano , Leite Humano , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Nutrientes , Apoio Nutricional , Estudos Multicêntricos como Assunto
3.
PLoS One ; 17(6): e0269339, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35709189

RESUMO

Use of face coverings has been shown to reduce transmission of SARS-CoV-2. Despite encouragements from the CDC and other public health entities, resistance to usage of masks remains, forcing government entities to create mandates to compel use. The state of Oklahoma did not create a state-wide mask mandate, but numerous municipalities within the state did. This study compares case rates in communities with mandates to those without mandates, at the same time and in the same state (thus keeping other mitigation approaches similar). Diagnosed cases of COVID-19 were extracted from the Oklahoma State Department of Health reportable disease database. Daily case rates were established based upon listed city of residence. The daily case rate difference between each locality with a mask mandate were compared to rates for the portions of the state without a mandate. All differences were then set to a d0 point of reference (date of mandate implementation). Piecewise linear regression analysis of the difference in SARS-CoV-2 infection rates between mandated and non-mandated populations before and after adoption of mask mandates was then done. Prior to adopting mask mandates, those municipalities that eventually adopted mandates had higher transmission rates than the rest of the state, with the mean case rate difference per 100,000 people increasing by 0.32 cases per day (slope of difference = 0.32; 95% CI 0.13 to 0.51). For the post-mandate time period, the differences are decreasing (slope of -0.24; 95% CI -0.32 to -0.15). The pre- and post- mandate slopes differed significantly (p<0.001). The change in slope direction (-0.59; 95% CI -0.80 to -0.37) shows a move toward reconvergence in new case diagnoses between the two populations. Compared to rates in communities without mask mandates, transmission rates of SARS-CoV-2 slowed notably in those communities that adopted a mask mandate. This study suggests that government mandates may play a role in reducing transmission of SARS-CoV-2, and other infectious respiratory conditions.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Máscaras , Oklahoma/epidemiologia , SARS-CoV-2
4.
Plants (Basel) ; 11(4)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35214858

RESUMO

We know little about the underlying genetic control of phenotypic patterns of seed traits across large-scale geographic and environmental gradients. Such knowledge is important for understanding the evolution of populations within species and for improving species conservation. Therefore, to test for genetic variation in Plantago lanceolata, we made reciprocal crosses between northern and southern genotypes that span the species' range in Europe. The results provide evidence of transgenerational genetic effects on seed mass and germination timing. Northern mothers produced larger seeds with delayed germination, in contrast to southern mothers, which produced smaller seeds with accelerated germination. A maternal latitude affected both the seed coat, solely maternal tissue, and embryo/endosperm tissues. Thus, latitudinal variation in seed size and germination timing can be explained, in part, by the direct influence of maternal genotype, independent of zygotic genes that parents pass directly to the embryo and endosperm. Data suggest that researchers exploring the existence and evolution of large-scale geographic variation within species test for transgenerational genetic effects. In addition, data suggest that transgenerational control of seed traits should be considered when developing procedures designed to facilitate species conservation and restoration.

5.
Ecol Evol ; 11(9): 4140-4157, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33976799

RESUMO

In exploring the roles of phenotypic plasticity in the establishment and early evolution of invading species, little empirical attention has been given to the importance of correlational selection acting upon suites of functionally related plastic traits in nature. We illustrate how this lack of attention has limited our ability to evaluate plasticity's role during invasion and also, the costs and benefits of plasticity. We addressed these issues by transplanting clones of European-derived Plantago lanceolata L. genotypes into two temporally variable habitats in the species' introduced range in North America. Phenotypic selection analyses were performed for each habitat to estimate linear, quadratic, and correlational selection on phenotypic trait values and plasticities in the reproductive traits: flowering onset and spike and scape lengths. Also, we measured pairwise genetic correlations for our "colonists." Results showed that (a) correlational selection acted on trait plasticity after transplantation, (b) selection favored certain combinations of genetically correlated and uncorrelated trait values and plasticities, and (c) using signed, instead of absolute, values of plasticity in analyses facilitated the detection of correlational selection on trait value-plasticity combinations and their adaptive value. Based on our results, we urge future studies on species invasions to (a) measure correlational selection and (b) retain signed values of plasticity in order to better discriminate between adaptive and maladaptive plasticity.

6.
Hear Res ; 395: 108027, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659614

RESUMO

OBJECTIVE: The present study compared wave I amplitude of auditory brainstem responses (ABRs), a potential indicator of cochlear synaptopathy, among musicians and non-musicians with normal audiograms. DESIGN: Noise exposure background (NEB) was evaluated using an online questionnaire. Two-channel ABRs were recorded from the left ear using click stimuli. One channel utilized an ipsilateral tiptrode, and another channel utilized an ipsilateral mastoid electrode. ABRs were collected at 90, 75, and 60 dBnHL. A mixed model was used to analyze the effect of group, electrodes, and stimulus levels on ABR wave I amplitude. STUDY SAMPLE: 75 collegiate students with normal hearing participated in the study and were grouped into a non-music major group (n = 25), a brass major group (n = 25), and a voice major group (n = 25). RESULTS: The NEB was negatively associated with the action potential (AP) and ABR wave I amplitude for click intensity levels at 75 dBnHL. The mean amplitude of the ABR wave I was not significantly different between the three groups. CONCLUSION: The weak negative association of AP and ABR wave I amplitude with NEB cannot be solely attributed to evidence of cochlear synaptopathy in humans as the possibility of hair cell damage cannot be ruled out. Future research should investigate the effects of reduced cochlear output on the supra-threshold speech processing abilities of student musicians.


Assuntos
Cóclea , Perda Auditiva Provocada por Ruído , Audiometria de Tons Puros , Limiar Auditivo , Potenciais Evocados Auditivos do Tronco Encefálico , Audição , Humanos , Música , Ruído/efeitos adversos
8.
J Manag Care Spec Pharm ; 26(5): 600-609, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32347180

RESUMO

BACKGROUND: Diabetes requires close monitoring to achieve optimal outcomes and avoid adverse effects. Continuous glucose monitoring (CGM) is one approach to measuring glycemia and has become more widespread with recent advances in technology; however, ideal implementation of CGM into clinical practice is unknown. CGM can be categorized as personal CGM, which can be for at-home use to replace self-monitoring of blood glucose, or professional CGM (proCGM), which is used intermittently under the direction of a health care professional. The expanding role of the clinical pharmacist allows pharmacists to be at the forefront of implementing proCGM technology, but literature on the effect of pharmacist-driven proCGM is lacking. Pharmacists and physicians within 1 physician-owned clinic used proCGM technology differently. Pharmacists conducted 1 or 2 office visits to interpret data and make interventions, while physicians interpreted data 1 time and relayed interventions via phone. OBJECTIVES: To (a) compare the change in hemoglobin A1c from baseline to 6 months between the different methods of proCGM implementation, and (b) describe and compare the clinical interventions made as a result of the different methods of proCGM implementation. METHODS: In this retrospective cohort study, adults identified in the electronic medical record via Current Procedural Terminology code 95250 or 95251 undergoing proCGM with CGM data interpreted and baseline A1c ≥ 7% were included. Patients with additional CGM use within the 6-month follow-up period were excluded. Data collection included demographics, A1c at baseline and during the 6-month follow-up period, and CGM-associated interventions. Patients were categorized as undergoing 1 pharmacist-driven encounter (RPh1), 2 pharmacist-driven encounters (RPh2), or 1 physician-driven encounter (MD1) for proCGM implementation. Combined RPh1 and RPh2 (cRPh) data were also used for analysis. The primary outcome was change in A1c from baseline to 6 months, which was evaluated by analysis of covariance. RESULTS: Of 378 patient charts reviewed, 315 instances of proCGM implementation met inclusion criteria (58 RPh1, 35 RPh2, 222 MD1), and 253 had post-implementation A1c data for analysis of the primary outcome (52 RPh1, 30 RPh2, 171 MD1). Baseline A1c was 8.4%, 8.8%, and 9.1% with mean reduction from baseline to 6 months of 1.0%, 1.3%, and 0.6%, respectively. cRPh patients experienced a greater mean reduction in A1c compared with MD1 (P = 0.002). RPh2 patients had a statistically significant reduction compared with MD1 (P = 0.005), but RPh1 patients did not (P = 0.054). The number of CGM-associated pharmacological interventions was 1.33 for RPh1 patients, 1.63 for RPh2 at the first encounter and 1.34 at the second, and 1.17 for MD1. CONCLUSIONS: Pharmacist-driven implementation of proCGM was associated with greater A1c reductions and more pharmacological interventions versus physician-driven implementation. This study demonstrated improved clinical outcomes with pharmacists providing direct patient care through implementation of new diabetes technology. DISCLOSURES: No outside funding supported this study. The authors have nothing to disclose. Preliminary results of this work were presented at the American College of Clinical Pharmacy Virtual Poster Symposium, May 28-29, 2019. The abstract was not peer-reviewed because of enrollment in the Mentored Research Investigator Training (MeRIT) program. Final peer-reviewed results were presented at the American College of Clinical Pharmacy Annual Meeting; October 26-29, 2019; New York, NY.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/análise , Hipoglicemiantes/uso terapêutico , Assistência Farmacêutica/normas , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Garantia da Qualidade dos Cuidados de Saúde , Estudos Retrospectivos
9.
Int J Audiol ; 55(10): 571-9, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27399974

RESUMO

OBJECTIVE: A non-synonymous single nucleotide polymorphism (rs61742642; C to T, P386S) in the ligand-binding domain of human estrogen-related receptor beta (ESRRß) showed possible association to noise-induced hearing loss (NIHL) in our previous study. DESIGN: This study was conducted to examine the effect of the ESRRß rs61742642 T variant on temporary threshold shift (TTS). TTS was induced by 10 minutes of exposure to audiometric narrow-band noise centered at 2000 Hz. Hearing thresholds and distortion product otoacoustic emissions input output function (DP IO) at 2000, 3000, and 4000 Hz were measured before and after the noise exposure. STUDY SAMPLE: Nineteen participants with rs61742642 CT genotype and 40 participants with rs61742642 CC genotype were recruited for the study. RESULTS: Participants with the CT genotype acquired a significantly greater TTS without convincing evidence of greater DP IO temporary level shift (DPTLS) compared to participants with the CC genotype. CONCLUSION: The results indicated that the ESRRß polymorphism is associated with TTS. Future studies were recommended to explore molecular pathways leading to increased susceptibility to NIHL.


Assuntos
Fadiga Auditiva , Perda Auditiva Provocada por Ruído/genética , Polimorfismo de Nucleotídeo Único , Receptores de Estrogênio/genética , Estimulação Acústica , Audiometria de Tons Puros , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/fisiopatologia , Heterozigoto , Homozigoto , Humanos , Masculino , Emissões Otoacústicas Espontâneas , Fenótipo , Fatores de Risco
10.
Int J Audiol ; 54(10): 645-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25938503

RESUMO

OBJECTIVE: Noise-induced hearing loss (NIHL) is a worldwide health problem and a growing concern among young people. Although some people appear to be more susceptible to NIHL, genetic association studies lack a specific phenotype. We tested the feasibility of a bilateral 4000-6000 Hz audiometric notch as a phenotype for identifying genetic contributions to hearing loss in young adults. DESIGN: A case-control-control study was conducted to examine selected SNPs in 52 genes previously associated with hearing loss and/or expressed in the cochlea. A notch was defined as a minimum of a 15-dB drop at 4000-6000 Hz from the previous best threshold with a 5-dB 'recovery' at 8000 Hz. STUDY SAMPLE: Participants were 252 individuals of European descent taken from a population of 640 young adults who are students of classical music. Participants were grouped as No-notch (NN), Unilateral Notch (UN), or Bilateral Notch (BN). RESULTS: The strongest evidence of a genetic association with the 4000-6000 Hz notch was a nonsynonymous SNP variant in the ESRR- gene (rs61742642:C> T, P386S). Carriers of the minor allele accounted for 26% of all bilateral losses. CONCLUSION: This study indicates that the 4000-6000 Hz bilateral notch is a feasible phenotype for identifying genetic susceptibility to hearing loss.


Assuntos
Audiometria/métodos , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/genética , Audição/genética , Ruído/efeitos adversos , Polimorfismo de Nucleotídeo Único , Estimulação Acústica , Adolescente , Adulto , Limiar Auditivo , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Perda Auditiva Provocada por Ruído/fisiopatologia , Humanos , Masculino , Fenótipo , Projetos Piloto , Valor Preditivo dos Testes , Fatores de Risco , Adulto Jovem
11.
Br J Sports Med ; 49(2): 79-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23922282

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) injury prevention programmes have shown mixed results, which may be due to differing emphasis on training components. The purpose of this study was to (1) quantify the overall and relative duration of each training component encompassed within these programmes and (2) examine the effect of these durations on ACL injury rates. METHODS: A systematic review was completed and meta-analyses performed on eligible studies to produce a pooled OR estimate of the effectiveness of these programmes. Meta-regression was used to detect any relationship that programme duration and the duration of individual training components had on ACL injury rates. RESULTS: 13 studies were included for review. Results of the meta-analyses revealed a significant reduction of injuries after preventative training programmes for all ACL injuries (pooled OR estimate of 0.612, 95% CI 0.44 to 0.85; p=0.004) and for non-contact ACL injuries (OR 0.351, 95% CI 0.23 to 0.54; p<0.001). Results of meta-regression analysis revealed that a greater duration of balance training was associated with a higher injury risk for ACL injury (p=0.04), while greater durations of static stretching was associated with a lower injury risk for non-contact ACL injuries (p=0.04). CONCLUSIONS: While ACL prevention programmes are successful in reducing the risk of ACL injury, the ideal combination and emphasis of training components within these programmes remains unclear. Evidence indicates that greater emphases on balance training and static stretching may be associated with an increase and decrease in injury risk, respectively.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos em Atletas/prevenção & controle , Terapia por Exercício/métodos , Retroalimentação , Humanos , Ruptura/prevenção & controle , Fatores de Tempo
12.
Am J Bot ; 100(12): 2485-93, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24285569

RESUMO

PREMISE OF THE STUDY: Understanding how plant reproduction responds to temperature has become increasingly important because of global climate change. Temperature-sensitive plasticity in floral reflectance is likely involved in some of these responses. Such plasticity, which underlies thermoregulatory ability, affects reproductive success in Plantago lanceolata. To see whether other Plantago species also show thermal plasticity in reflectance, we measured plasticity in P. lagopus, P. coronopus, P. major, P. subulata, P. albicans, P. tomentosa, P. maritima, and P. weldenii. METHODS: We induced plants to flower at two temperatures in growth chambers and recorded floral reflectance (362-800 nm). KEY RESULTS: All species were thermally plastic in visible and near-IR regions. Species and populations differed in response. Some showed greater variation in reflectance at warm temperature, while the reverse was true for others. Plasticity was greatest in the P. lanceolata clade. Cosmopolitan species were not more plastic than were geographically restricted species. CONCLUSIONS: The data suggest that (1) thermal plasticity is an ancestral trait for Plantago, (2) plasticities in visible and near-IR regions have evolved along different pathways within the genus, and (3) phylogenetic history partially explains this evolutionary divergence. Our data combined with those of previous studies suggest that global climate change will modify floral reflectance and color in many plant species. These modifications are likely to affect plant reproductive success.


Assuntos
Mudança Climática , Cor , Flores/fisiologia , Fenótipo , Filogenia , Plantago/genética , Temperatura , Clima , Plantago/crescimento & desenvolvimento , Plantago/fisiologia , Reprodução
13.
Am Nat ; 180(3): 342-53, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22854077

RESUMO

To better understand the evolution of phenotypic plasticity and thermoregulation and their potential value for ectotherms in the face of global warming, we conducted field experiments to measure their effects on fitness and their association with reproductive phenology in Plantago lanceolata in a thermally variable environment. We measured the reproductive timing and success of genotypes varying in thermoregulation, as mediated by floral-reflectance plasticity. Results were consistent with the hypothesis that thermoregulation is more adaptive when thermally variable reproductive seasons are shorter and cooler. Strong thermoregulation/plasticity increased reproductive success during the cool portion of the reproductive season but not during the warm portion. Directional selection that favored strongly thermoregulating genotypes early in the season shifted to stabilizing selection that favored genotypes with weaker thermoregulation later in the season. Thermoregulation and reproductive phenology were negatively correlated. Although reproductive onset and duration were similar between genotypes, strong thermoregulators produced more and larger spikes (clutches) early; weak thermoregulators produced more spikes late. Results suggest that with atmospheric warming, the benefit of raising body temperature via thermoregulation when it is cool should decline in extant populations. The negative correlation between thermoregulation and phenology should accelerate the evolutionary shift toward thermoconformity, that is, reduced plasticity.


Assuntos
Flores/fisiologia , Plantago/fisiologia , Seleção Genética , Temperatura , Mudança Climática , Genótipo , Fenótipo , Reprodução , Estações do Ano
14.
Br J Math Stat Psychol ; 65(3): 499-510, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22335527

RESUMO

Using Tukey-Kramer versus the ANOVA F-test as the omnibus test of the Hayter-Fisher procedure for comparing all pairs of normally distributed means, when sample sizes are unequal, is investigated. Simulation results suggest that using Tukey-Kramer leads to as much or more any-pairs power compared to using the F-test for certain patterns of mean differences, and equivalent per-pair and all-pairs power for all cases. Furthermore, using Tukey-Kramer results in a consonant test procedure, where there cannot be disagreement between the results of the omnibus test and the subsequent pairwise tests. The results suggest that when sample sizes are unequal, Tukey-Kramer may be preferred over the F-test as the omnibus test for the Hayter-Fisher procedure.


Assuntos
Modelos Estatísticos , Testes Psicológicos/estatística & dados numéricos , Simulação por Computador/estatística & dados numéricos , Humanos , Projetos de Pesquisa/estatística & dados numéricos , Tamanho da Amostra , Distribuições Estatísticas
15.
J Nat Prod ; 74(7): 1621-9, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21661731

RESUMO

It is often argued that the efficacy of herbal medicines is a result of the combined action of multiple constituents that work synergistically or additively. Determining the bioactive constituents in these mixtures poses a significant challenge. We have developed an approach to address this challenge, synergy-directed fractionation, which combines comprehensive mass spectrometry profiling with synergy assays and natural products isolation. The applicability of synergy-directed fractionation was demonstrated using the botanical medicine goldenseal (Hydrastis canadensis) as a case study. Three synergists from goldenseal were identified, sideroxylin, 8-desmethyl-sideroxylin, and 6-desmethyl-sideroxylin. These flavonoids synergistically enhance the antimicrobial activity of the alkaloid berberine (also a constituent of H. canadensis) against Staphylococcus aureus by inhibition of the NorA multidrug resistance pump. The flavonoids possess no inherent antimicrobial activity against S. aureus; therefore, they could have been missed using traditional bioactivity-directed fractionation. The flavonoid synergists are present at higher concentration in extracts from H. canadensis leaves, while the antimicrobial alkaloid berberine is present at higher levels in H. canadensis roots. Thus, it may be possible to produce an extract with optimal activity against S. aureus using a combination of goldenseal roots and leaves.


Assuntos
Flavonoides/isolamento & purificação , Hydrastis/química , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos , Proteínas de Bactérias/efeitos dos fármacos , Alcaloides de Berberina/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/efeitos dos fármacos , North Carolina , Folhas de Planta/química , Raízes de Plantas/química
16.
Am Nat ; 175(3): 335-49, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20100107

RESUMO

Adaptive phenotypic plasticity in thermally sensitive traits, that is, thermal acclimation, generally increases with increasing latitude and altitude. The presumed explanation is that high-latitude/altitude organisms have evolved greater acclimation ability because of exposure to greater temperature fluctuations. Using a conceptual model of the thermal environment during the reproductive season, we tested this hypothesis against an alternative that plasticity is greater because of increased exposure to specific temperatures that strongly select for thermal acclimation. We examined geographic variation in floral reflectance/color plasticity among 29 European populations of a widespread perennial herb, Plantago lanceolata. Individuals partially thermoregulate reproduction through temperature-sensitive plasticity in floral reflectance/color. Plasticity was positively correlated with latitude and altitude. Path analyses support the hypothesis that the thermal environment mediates these geographic effects. Plasticity declined as seasonal temperature range increased, and it increased as duration of the growing season shortened and as the proportion of time exposed to temperatures favoring thermoregulation increased. Data provide evidence that floral reflectance/color plasticity is adaptive and that it has evolved in response not to the magnitude of temperature variation during the reproductive season but rather to the relative exposure to low temperatures, which favor thermoregulation.


Assuntos
Aclimatação , Geografia , Plantago/fisiologia , Temperatura , Cor , Flores/anatomia & histologia , Flores/fisiologia , Plantago/anatomia & histologia , Reprodução , Estações do Ano
17.
J Speech Lang Hear Res ; 52(1): 118-29, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18664682

RESUMO

PURPOSE: This study examined differences in voiced consonant-vowel (CV) perception in older listeners with normal hearing and in 2 groups of older listeners with matched hearing losses: those with good and those with poor word recognition scores. METHOD: Thirty-six participants identified CVs from an 8-item display from the natural voiced initial consonants/b, d, g, m, n, eth, v and z/in three vowel contexts (/a, o, u/) spoken by a male and a female talker. RESULTS: The listeners with hearing loss and poor word recognition scores (WRS) made more of the same types of errors, as well as errors not made by listeners with hearing loss and good word recognition. Errors above chance rates for these listeners were highest in the context of /a/ and were similar in the contexts of /o/ and /u/. Sequential information analyses (SINFAs) verified that information was transmitted least efficiently in the context of /a/. The results yielded a list of consonant confusions unique to listeners with poor WRS. CONCLUSIONS: Listeners with poor WRS have more difficulty identifying voiced initial consonants in CV syllables than do listeners with good WRS. These listeners made some systematic errors, but most errors were nonsystematic, perhaps due to the low level of feature information transmitted.


Assuntos
Perda Auditiva/psicologia , Fonética , Percepção da Fala , Idoso , Idoso de 80 Anos ou mais , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Modelos Estatísticos , Reconhecimento Psicológico
18.
New Phytol ; 181(3): 662-71, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19021863

RESUMO

In many plant species, the alternative respiratory pathway consisting of alternative oxidase (AOX) is affected by growth temperature. The adaptive significance of this temperature-sensitivity is unresolved. Here, leaf and spike (flower cluster) AOX protein content and spike/floral reflectance of genotypes from European Plantago lanceolata populations found in regions differing in reproductive season temperatures were measured. Cloned genotypes grown at controlled warm and cool temperatures were used to assess the natural within- and between-population variation in AOX content, temperature-sensitive phenotypic plasticity in content, and the relationship between AOX and temperature-sensitive floral/spike reflectance. AOX content and plasticity were genetically variable. Leaf AOX content, although greater at cool temperature, was relatively low and not statistically different across populations. Spike AOX content was greater than in leaves. Spike AOX plasticity differed significantly among populations and climate-types and showed significant negative correlation with floral reflectance plasticity, which also varied among populations. Genotypes with more AOX at cool than at warm temperature had greater floral reflectance plasticity; genotypes with relatively more AOX at warm temperature had less floral reflectance plasticity. The data support the hypothesis that plasticity of AOX content in reproductive tissues is associated with long-term thermal acclimatization.


Assuntos
Flores/fisiologia , Oxirredutases/metabolismo , Plantago/enzimologia , Temperatura , Análise de Variância , Temperatura Baixa , Eletroforese em Gel de Poliacrilamida , Genótipo , Temperatura Alta , Proteínas Mitocondriais , Fenótipo , Proteínas de Plantas , Plantago/genética , Dinâmica Populacional
19.
Appl Opt ; 47(14): 2660-79, 2008 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-18470263

RESUMO

We propose a direct method of partitioning the particulate spectral scattering coefficient of the marine hydrosol based on the concurrent determination of the concentrations of particulate mineral and organic matter (the total mass of optically active scattering material exclusive of water) with the particulate spectral scattering coefficient. For this we derive a Model II multiple linear regression model. The multiple linear regression of the particulate spectral scattering coefficient against the independent variables, the concentrations of particulate inorganic matter and particulate organic matter, yields their mass-specific spectral scattering cross sections. The mass-specific spectral scattering cross section is simply the particle scattering cross section normalized to the particle mass, a fundamental optical efficiency parameter for the attenuation of electromagnetic radiation [Absorption and Scattering of Light by Small Particles, (Wiley-Interscience, 1983), pp. 80-81, 289]. It is possible to infer the optical properties of the suspended matter from the mass-specific spectral scattering cross sections. From these cross sections we partition the particulate spectral scattering coefficient into its major components.


Assuntos
Óptica e Fotônica , Espalhamento de Radiação , Água/química , Fenômenos Geológicos , Geologia , Modelos Estatísticos , Oceanos e Mares , Tamanho da Partícula , Radiação , Análise de Regressão , Tomografia Óptica/métodos
20.
J Econ Entomol ; 99(3): 1002-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16813343

RESUMO

In applied entomological experiments, when the response is a count-type variable, certain transformation remedies such as the square root, logarithm (log), or rank transformation are often used to normalize data before analysis of variance. In this study, we examine the usefulness of these transformations by reanalyzing field-collected data from a split-plot experiment and by performing a more comprehensive simulation study of factorial and split-plot experiments. For field-collected data, significant interactions were dependent upon the type of transformation. For the simulation study, Poisson distributed errors were used for a 2 by 2 factorial arrangement, in both randomized complete block and split-plot settings. Various sizes of main effects were induced, and type I error rates and powers of the tests for interaction were examined for the raw response values, log-, square root-, and rank-transformed responses. The aligned rank transformation also was investigated because it has been shown to perform well in testing interactions in factorial arrangements. We found that for testing interactions, the untransformed response and the aligned rank response performed best (preserved nominal type I error rates), whereas the other transformations had inflated error rates when main effects were present. No evaluations of the tests for main effects or simple effects have been conducted. Potentially these transformations will still be necessary when performing these tests.


Assuntos
Entomologia/métodos , Estatística como Assunto/métodos , Análise de Variância , Simulação por Computador , Modelos Biológicos
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