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1.
Ecol Evol ; 14(2): e10947, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38357589

RESUMO

Understory assemblages associated with canopy-forming species such as trees, kelps, and rockweeds should respond strongly to climate stressors due to strong canopy-understory interactions. Climate change can directly and indirectly modify these assemblages, particularly during more stressful seasons and climate scenarios. However, fully understanding the seasonal impacts of different climate conditions on canopy-reliant assemblages is difficult due to a continued emphasis on studying single-species responses to a single future climate scenario during a single season. To examine these emergent effects, we used mesocosm experiments to expose seaweed assemblages associated with the canopy-forming golden rockweed, Silvetia compressa, to elevated temperature and pCO2 conditions reflecting two projected greenhouse emission scenarios (RCP 2.6 [low] & RCP 4.5 [moderate]). Assemblages were grown in the presence and absence of Silvetia, and in two seasons. Relative to ambient conditions, predicted climate scenarios generally suppressed Silvetia biomass and photosynthetic efficiency. However, these effects varied seasonally-both future scenarios reduced Silvetia biomass in summer, but only the moderate scenario did so in winter. These reductions shifted the assemblage, with more extreme shifts occurring in summer. Contrarily, future scenarios did not shift assemblages within Silvetia Absent treatments, suggesting that climate primarily affected assemblages indirectly through changes in Silvetia. Mesocosm experiments were coupled with a field Silvetia removal experiment to simulate the effects of climate-mediated Silvetia loss on natural assemblages. Consistent with the mesocosm experiment, Silvetia loss resulted in season-specific assemblage shifts, with weaker effects observed in winter. Together, our study supports the hypotheses that climate-mediated changes to canopy-forming species can indirectly affect the associated assemblage, and that these effects vary seasonally. Such seasonality is important to consider as it may provide periods of recovery when conditions are less stressful, especially if we can reduce the severity of future climate scenarios.

2.
Nat Commun ; 14(1): 3394, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296168

RESUMO

To alleviate the energy and environmental crisis, in the last decades, energy harvesting by utilizing optical control has emerged as a promising solution. Here we report a polar crystal that exhibits photoenergy conversion and energy storage upon light irradiation. The polar crystal consists of dinuclear [CoGa] molecules, which are oriented in a uniform direction inside the crystal lattice. Irradiation with green light induces a directional intramolecular electron transfer from the ligand to a low-spin CoIII centre, and the resultant light-induced high-spin CoII excited state is trapped at low temperature, realizing energy storage. Additionally, electric current release is observed during relaxation from the trapped light-induced metastable state to the ground state, because the intramolecular electron transfer in the relaxation process is accompanied with macroscopic polarization switching at the single-crystal level. It demonstrates that energy storage and conversion to electrical energy is realized in the [CoGa] crystals, which is different from typical polar pyroelectric compounds that exhibit the conversion of thermal energy into electricity.


Assuntos
Eletricidade , Temperatura Alta , Temperatura , Transporte de Elétrons , Temperatura Baixa
3.
Oecologia ; 199(4): 859-869, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35907124

RESUMO

Prey state and prey density mediate antipredator responses that can shift community structure and alter ecosystem processes. For example, well-nourished prey at low densities (i.e., prey with higher per capita predation risk) should respond strongly to predators. Although prey state and density often co-vary across habitats, it is unclear if prey responses to predator cues are habitat-specific. We used mesocosms to compare the habitat-specific responses of purple sea urchins (Strongylocentrotus purpuratus) to waterborne cues from predatory lobsters (Panulirus interruptus). We predicted that urchins from kelp forests (i.e., in well-nourished condition) tested at low densities typically observed in this habitat would respond more strongly to predation risk than barren urchins (i.e., in less nourished condition) tested at high densities typically observed in this habitat. Indeed, when tested at densities associated with respective habitats, urchins from forests, but not barrens, reduced kelp grazing by 69% when exposed to lobster risk cues. Barren urchins that were unresponsive to predator cues at natural, high densities suddenly responded strongly to lobster cues when conspecific densities were reduced. Strong responses of low densities of barren urchins persisted across feeding history (i.e. 0-64 days of starvation). This suggests that barren urchins can respond to predators but typically do not because of high conspecific densities. Because high densities of urchins in barrens should weaken the non-consumptive effects of lobsters, urchins in these habitats may continue to graze in the presence of predators thereby providing a feedback that maintains urchin barrens.


Assuntos
Kelp , Comportamento Predatório , Animais , Sinais (Psicologia) , Ecossistema , Cadeia Alimentar , Ouriços-do-Mar/fisiologia
4.
Ecol Evol ; 12(3): e8722, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35356584

RESUMO

Interspecific interactions between plants influence plant phenotype, distribution, abundance, and community structure. Each of these can, in turn, impact sediment biogeochemistry. Although the population and community level impacts of these interactions have been extensively studied, less is known about their effect on sediment biogeochemistry. This is surprising given that many plants are categorized as foundation species that exert strong control on community structure. In southern California salt marshes, we used clipping experiments to manipulate aboveground neighbor presence to study interactions between two dominant plants, Pacific cordgrass (Spartina foliosa) and perennial pickleweed (Sarcocornia pacifica). We also measured how changes in cordgrass stem density influenced sediment biogeochemistry. Pickleweed suppressed cordgrass stem density but had no effect on aboveground biomass. For every cordgrass stem lost per square meter, porewater ammonium increased 0.3-1.0 µM. Thus, aboveground competition with pickleweed weakened the effects of cordgrass on sediment biogeochemistry. Predictions about plant-soil feedbacks, especially under future climate scenarios, will be improved when plant-plant interactions are considered, particularly those containing dominant and foundation species.

5.
Ecology ; 103(5): e3623, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34967951

RESUMO

Omnivory is ubiquitous in ecological communities. Yet, we lack a consensus of how plant alternative resources impact the ability of omnivores to suppress prey populations. Previous work suggests that plant alternative resources can increase, decrease, or have no effect on the magnitude of omnivore-prey interactions. This discrepancy may arise from (1) the ability of omnivore populations to respond to plant alternative resources and (2) identity-specific effects of plant alternative resources. We used a meta-analysis to examine how omnivore population responses and the identity of plant alternative resources affect (1) omnivore predation rates (mainly reported as per capita predation rate) and (2) omnivore impacts on prey population density. Plant alternative resources reduced omnivore predation rate regardless of identity. The suppression of the predation rate by flowers and flowering plants was magnified when pollen alone was tested as the alternative resource. Surprisingly, plant alternative resource availability reduced prey density, suggesting that omnivore predation increased with plant alternative resources. This discrepancy (plant alternative resources not only decreased omnivore predation rates but also decreased prey density) resulted from experimental differences in the ability of omnivore populations to respond to plant alternative resources. In the presence of plant alternative resources, allowing omnivore population responses decreased prey density, while not allowing population responses increased prey density. Because omnivores commonly suppress prey density in the presence of plant alternative resources when population responses of omnivores are allowed, the effectiveness of biological control may depend upon the availability of such resources and the facilitation of population responses.


Assuntos
Artrópodes , Animais , Cadeia Alimentar , Plantas , Densidade Demográfica , Dinâmica Populacional , Comportamento Predatório/fisiologia
6.
Nat Commun ; 12(1): 4836, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376674

RESUMO

Pyroelectricity plays a crucial role in modern sensors and energy conversion devices. However, obtaining materials with large and nearly constant pyroelectric coefficients over a wide temperature range for practical uses remains a formidable challenge. Attempting to discover a solution to this obstacle, we combined molecular design of labile electronic structure with the crystal engineering of the molecular orientation in lattice. This combination results in electronic pyroelectricity of purely molecular origin. Here, we report a polar crystal of an [FeCo] dinuclear complex exhibiting a peculiar pyroelectric behavior (a substantial sharp pyroelectric current peak and an unusual continuous pyroelectric current at higher temperatures) which is caused by a combination of Fe spin crossover (SCO) and electron transfer between the high-spin Fe ion and redox-active ligand, namely valence tautomerism (VT). As a result, temperature dependence of the pyroelectric behavior reported here is opposite from conventional ferroelectrics and originates from a transition between three distinct electronic structures. The obtained pyroelectric coefficient is comparable to that of polyvinylidene difluoride at room temperature.

8.
Ecology ; 102(2): e03244, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33191507

RESUMO

Burrowing animals can profoundly influence the structure of surrounding communities, as well as the performance of individual species. Changes in the community structure of burrowing animals or plants together with changing abiotic parameters could shift the influence of burrowers on surrounding habitats. For example, prior studies in salt marshes suggest that fiddler crabs stimulate cordgrass production, but leaf-grazing crabs suppress cordgrass production. Unfortunately, testing this prediction and others are impeded because few studies have examined crab impacts on the plant community and across multiple sites, multiple years, or both. This challenges our ability to predict how burrowing animals will influence plant community structure, and when and where these impacts will occur. We manipulated the densities of the dominant burrowing crabs in plant assemblages dominated by Pacific cordgrass (Spartina foliosa) and perennial pickleweed (Sarcocornia pacifica) at three sites in southern California for three years (2016, 2017, 2018). Crab impacts on plant community structure differed among each of our three sites. In contrast to our predictions, (1) leaf-grazing crabs (Pachygrapsus crassipes) had positive effects on cordgrass cover at one site and no effect on cordgrass production at a nearby site in the same marsh and (2) fiddler crabs (Uca crenulata) did not stimulate cordgrass production at another marsh. Because crabs affected traits of cordgrass, but not pickleweed, in the direction consistent with changes in cordgrass cover, we propose that marsh-specific crab effects on community structure were largely mediated through changes in cordgrass, as opposed to pickleweed. Importantly, crabs facilitated cordgrass during marsh-wide cordgrass loss, suggesting that crabs may mitigate environmental stress for this ecologically important plant. Because cordgrass abundance can be a critical measure of marsh functioning and is often a restoration target, we suggest that managing cordgrass populations would benefit from additional information about crab populations and their impacts among years, and among and within marshes.


Assuntos
Braquiúros , Animais , Ecossistema , Poaceae , Áreas Alagadas
9.
Spartan Med Res J ; 5(1): 12748, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33655179

RESUMO

INTRODUCTION: In the US, ultrasound in Emergency Medicine (EM) is widely considered the standard of care in clinical practice amongst most Emergency Department providers. At the authors' institution and affiliates, there were a variety of health care providers utilizing ultrasound for clinical practice, and their skill levels varied, dependent on training and exposure. As an attempt to standardize credentialing practice and determine need for additional training thresholds, the authors endeavored to perform a skills assessment utilizing both written and clinical based practical assessments. METHODS: A 7 point questionnaire was administered to a convenience sample of providers requesting formal training information, number of ultrasounds performed, and self-assessed competency. A 10 point written assessment with ultrasound knowledge and clinical application questions was also administered. A subsequent clinical assessment on live humans and models was then performed with multiple stations assessing 15 different instrumentation skills and technique, as well as image interpretation and evaluation. RESULTS: A total of 23 attending EM board-certified physicians, and four advanced practice providers (PA and NP) took the credentialing assessments scoring an average of 7.3 out of 10 (SD 0.83) for the written assessment. Twenty (71%) of the 28 tested passed the clinical evaluation on their initial attempt. Five (17%) passed on a first remediation. Three (10%) required more than one initial revision attempt. All those who did remediate were able to complete the revision with a passing score. CONCLUSIONS: Overall, the testing was considered a successful process. This program appears to have offered a level of standardization that was appealing to the credentialing body at our institution. We were able to assess to a level of competence considered standard of care by national credentialing bodies.

10.
J Med Imaging Radiat Oncol ; 63(3): 378-382, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30623607

RESUMO

INTRODUCTION: The multidisciplinary team meeting (MDTM) approach is accepted as standard of care to optimise treatment for patients diagnosed with cancer. This retrospective audit reviews the proportion of patients whose care is being discussed at cancer MDTMs within the Sunshine Coast Hospital and Health Service (SCHHS). METHODS: Patients included were those diagnosed with cancer within the SCHHS between 2010 and 2015, and subsequently referred to a public MDTM for discussion. Data were extracted from the Queensland Cancer Control Analysis Team (QCCAT) database regarding the incidence of breast, lung, upper gastrointestinal (GI), colorectal, genitourinary and malignant haematological cancers and the number of patients referred to the corresponding MDTM. RESULTS: Data from 2015 show referral rates to MDTMs as follows: lung 100%, upper gastrointestinal 100%, colorectal 64%, breast 60%, malignant haematology 40% and genitourinary 28%. Of the genitourinary presentations, 70% were prostate cases and 14% bladder cases. Review of genitourinary MDTM outcomes found that, of the patients with prostate cancer discussed, 30% were metastatic, 19% were poor surgical candidates and 15% had biochemical recurrence. CONCLUSION: This audit demonstrates variable utilisation of MDTMs between tumour streams. Our study shows a high and increasing referral rate to all tumour stream MDTMs except for genitourinary. This suggests a possible underutilisation of genitourinary MDTMs to discuss treatment options for patients with genitourinary cancer. Collaborative research is warranted to further investigate whether this is a local or widespread issue.


Assuntos
Comunicação Interdisciplinar , Neoplasias/terapia , Equipe de Assistência ao Paciente , Encaminhamento e Consulta/estatística & dados numéricos , Feminino , Humanos , Masculino , Queensland , Estudos Retrospectivos
11.
Ecology ; 99(7): 1574-1583, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29729184

RESUMO

Although trophic cascades were originally believed to be driven only by predators eating prey, there is mounting evidence that such cascades can be generated in large part via non-consumptive effects. This is especially important in cascades affecting habitat-forming foundation species that in turn, influence associated communities. Here, we use laboratory and field experiments to identify a trait-mediated indirect interaction between predators and an abundant kelp in a marine temperate reef system. Predation risk from a microcarnivorous fish, the señorita, suppressed grazing by the host-specific seaweed limpet, which in turn, influenced frond loss of the habitat-forming feather boa kelp. This trophic cascade was pronounced because minor amounts of limpet grazing decreased the strength required to break kelp fronds. Cues from fish predators mitigated kelp loss by decreasing limpet grazing; we found 86% of this indirect interaction between predator and kelp was attributed to the non-consumptive effect in the laboratory and 56% when applying the same effect size calculations to the field. In field manipulations, the non-consumptive effect of señorita was as strong as the total predator effect and most importantly, as strong as the uncaged, "open" treatment with natural levels of predators. Our findings demonstrate that the mere presence of this fish reduces frond loss of the feather boa kelp through a trait-mediated trophic cascade. Moreover, despite large volumes of water, current flow, and wave energy, we clearly demonstrate a strong non-consumptive effect via an apparent chemical cue from señorita, suggesting that chemically mediated trait-driven cascades may be more prevalent in subtidal marine systems than we are currently aware.


Assuntos
Kelp , Animais , Ecossistema , Peixes , Cadeia Alimentar , Comportamento Predatório
12.
Ecology ; 99(8): 1748-1758, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29846935

RESUMO

Intraspecific variation in primary producer induced defenses may affect how these defenses contribute to population and community regulation. For instance, inducible defenses may play larger roles in primary producer populations that are sensitive to low levels of grazing than populations that only respond to high levels of grazing. Although the incidence of herbivore-induced defenses is well documented, and there are examples of geographic variation in these defenses, we have limited knowledge of the factors that affect sensitivity to grazing (i.e., the minimum grazer density needed to elicit these responses) within and among populations. Filling this gap is necessary to understand the importance of these defenses under different conditions. To address whether the sensitivity of seaweed induced defenses varies geographically, we exposed Northern and Southern California populations of the seaweed Silvetia compressa to five densities of the snail Tegula funebralis, under ambient, regional environmental conditions. Southern seaweeds required high levels of grazing to induce defenses, while all levels of herbivory decreased Northern seaweed palatability. To better understand these different responses to low levels of grazing, we conducted common garden experiments to directly test the roles of experimental environment and herbivore source. Consistent with initial experiments, Northern Silvetia responded to low levels of grazing, regardless of environmental conditions, while Southern Silvetia never responded to low levels of grazing, even after being acclimated to Northern environmental conditions for 24 d. Additionally, Southern Silvetia did not respond to grazing by Northern snails, suggesting that herbivore source did not explain this geographic pattern in inducible seaweed defenses. Together, these observations suggest that the seaweed source explains this geographic pattern in sensitivity. Trade-offs with constitutive defenses did not help explain this pattern, as Southern Silvetia had weaker constitutive defenses than Northern seaweeds. This may be due to a combination of low grazing pressure and low predictability of attack in the South. Thus, population variation in sensitivity may be due to long-term differences in environmental histories, resulting in local adaptation or legacy effects from exposure to local conditions. Overall, our results indicate that these herbivore-induced responses may be more important in Northern Silvetia populations than Southern ones.


Assuntos
Phaeophyceae , Alga Marinha , Animais , California , Herbivoria , Caramujos
13.
Healthc (Amst) ; 6(4): 253-258, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28847571

RESUMO

BACKGROUND: Interventions designed to improve care and reduce costs for patients with the highest rates of hospital utilization (super-utilizers) continue to proliferate, despite conflicting evidence of cost savings. METHODS: We evaluated a practice transformation intervention that implemented team-based care and risk-stratification to match specific primary care resources based on need. This included an intensive outpatient clinic for super-utilizers. We used multivariate regression and a difference-in-differences approach to compare changes in mortality, utilization, and charges between the intervention group and a historical control. Sensitivity analyses tested the robustness of findings and revealed the inherent challenges associated with quasi-experimental designs. RESULTS: Observed charges for the intervention group were significantly lower than expected charges as derived by the trend of the historical control (p<0.04) resulting in total charge avoidance of approximately $26 million. While inpatient admissions were significantly higher (p<0.01), charges associated with total inpatient (p=0.01), intensive-care unit (p<0.05, not robust to sensitivity analyses), and surgery (p<0.01) were significantly lower than expected in the intervention group. One year mortality was significantly less in the intervention group (12.6% vs 11.5%, p<0.01). CONCLUSIONS: The use of tailored services, including a dedicated intensive outpatient clinic, for super-utilizers within a larger primary care practice transformation reduced mortality and provided significant savings, even while total hospitalizations increased. These savings were achieved through a reduction in the intensity of inpatient services. The unexpected finding of a reduction in ICU charges deserves further exploration. IMPLICATIONS: These findings suggest that intensity of inpatient service, and not merely volume of services, should be considered a focus for future intervention design and evaluated as an outcome. LEVEL OF EVIDENCE: Level III (Quasi-Experimental Design).


Assuntos
Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Assistência Centrada no Paciente/economia , Adulto , Colorado , Análise Custo-Benefício , Feminino , Mortalidade Hospitalar , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Assistência Centrada no Paciente/métodos
14.
Ecology ; 98(9): 2312-2321, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28590557

RESUMO

Long-standing theory predicts that the intensity of consumer-prey interactions declines with increasing latitude, yet for plant-herbivore interactions, latitudinal changes in herbivory rates and plant palatability have received variable support. The topic is of growing interest given that lower-latitude species are moving poleward at an accelerating rate due to climate change, and predicting local interactions will depend partly on whether latitudinal gradients occur in these critical biotic interactions. Here, we assayed the palatability of 50 seaweeds collected from polar (Antarctica), temperate (northeastern Pacific; California), and tropical (central Pacific; Fiji) locations to two herbivores native to the tropical and subtropical Atlantic, the generalist crab Mithraculus sculptus and sea urchin Echinometra lucunter. Red seaweeds (Rhodophyta) of polar and temperate origin were more readily consumed by urchins than were tropical reds. The decline in palatability with decreasing latitude is explained by shifts in tissue organic content along with the quantity and quality of secondary metabolites, degree of calcification or both. We detected no latitudinal shift in palatability of red seaweeds to crabs, nor any latitudinal shifts in palatability of brown seaweeds (Phaeophyta) to either crabs or urchins. Our results suggest that evolutionary pressure from tropical herbivores favored red seaweeds with lower palatability, either through the production of greater levels of chemical defenses, calcification, or both. Moreover, our results tentatively suggest that the "tropicalization" of temperate habitats is facilitated by the migration of tropical herbivores into temperate areas dominated by weakly defended and more nutritious foods, and that the removal of these competing seaweeds may facilitate the invasion of better-defended tropical seaweeds.


Assuntos
Herbivoria , Plantas , Animais , Regiões Antárticas , California , Clima , Mudança Climática , Ecossistema , Phaeophyceae , Ouriços-do-Mar , Alga Marinha
15.
J Cancer Educ ; 32(4): 814-819, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26932309

RESUMO

The majority of cancer patients receiving chemotherapy will consider taking complementary and alternative medicine (CAM) during their treatment. As biologically-active CAM may detrimentally interfere with chemotherapy treatment, cancer patients require evidence-based information on chemotherapy-CAM integration consequences. This study aimed to assess if the availability of a purpose-designed brochure within a cancer service aided doctors' discussions with their patients on CAM use and helped patients understand the effects of CAM during their chemotherapy treatment. Cancer care doctors consulting in an adult day unit completed a structured post-intervention feedback survey form (n = 17), and cancer patients receiving chemotherapy treatment were provided the brochure and completed the local health service consumer testing feedback form (n = 30). All cancer care doctors perceived a need for the brochure and recommended the brochure to their patients. All doctors thought the brochure made it easier for them to discuss CAM with their patients, and 59 % believed that it saved them time during patient consultations. Ninety percent of cancer patients reported the brochure had enough information to answer their CAM questions, and all patients thought the information was easy to read and understand. An evidence-based CAM-with-chemotherapy patient brochure was perceived to have enabled cancer care doctors to discuss CAM with their patients and to have answered patients' CAM questions.


Assuntos
Terapias Complementares/efeitos adversos , Tratamento Farmacológico/métodos , Folhetos , Educação de Pacientes como Assunto , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
16.
Asia Pac J Clin Oncol ; 12(3): 265-74, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27044569

RESUMO

AIM: To determine which types of complementary and alternative medicine (CAM) are being used by cancer patients commencing curative-intent chemotherapy, whether the CAM taken has the potential to affect treatment efficacy, the reasons for patients' decisions to use CAM and whether these patients would like information on CAM safety with chemotherapy. METHODS: Seventy-five solid tumor malignancy patients receiving curative-intent treatment attending a cancer care day unit were interviewed about their CAM use on the day of receiving their first dose of chemotherapy. RESULTS: Sixty percent of study participants were using CAM at the start of chemotherapy treatment. Biologically active CAM assessed as having potential to interact with prescribed chemotherapy was ingested by 27% of patients, all of whom had routinely used CAM prior to cancer diagnosis. CAM was used by 51% of patients for supportive care reasons and by 28% of patients with the intention of treating their cancer. Patients' CAM decision-making was influenced by advice from family and friends, practitioners and casual acquaintances. Thirteen percent of patients were told by a CAM advice-giver not to have chemotherapy. The majority of patients (84%) would have liked to receive information on which CAM is safe to use with chemotherapy before treatment commenced. CONCLUSIONS: Patients being treated with curative intent, particularly those with a history of CAM use, may be taking biologically active CAM with potential to compromise their chemotherapy treatment. These patients want cancer-care health professionals to provide them evidence-based information on safe CAM use with chemotherapy and may be contending with alternative health advice to not have chemotherapy.


Assuntos
Terapias Complementares , Neoplasias/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Educação de Pacientes como Assunto
17.
PeerJ ; 3: e1442, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26623195

RESUMO

Experimental mesocosm studies of rocky shore and estuarine intertidal systems may benefit from the application of natural tide cycles to better replicate variation in immersion time, water depth, and attendant fluctuations in abiotic and edaphic conditions. Here we describe a stand-alone microcontroller tide prediction open-source software program, coupled with a mechanical tidal elevation control system, which allows continuous adjustment of aquarium water depths in synchrony with local tide cycles. We used this system to monitor the growth of Spartina foliosa marsh cordgrass and scale insect herbivores at three simulated shore elevations in laboratory mesocosms. Plant growth decreased with increasing shore elevation, while scale insect population growth on the plants was not strongly affected by immersion time. This system shows promise for a range of laboratory mesocosm studies where natural tide cycling could impact organism performance or behavior, while the tide prediction system could additionally be utilized in field experiments where treatments need to be applied at certain stages of the tide cycle.

18.
PLoS One ; 10(8): e0135395, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26274491

RESUMO

Seaweed-herbivore interactions are often mediated by environmental conditions, yet the roles of emerging anthropogenic stressors on these interactions are poorly understood. For example, chemical contaminants have unknown consequences on seaweed inducible resistance and herbivore response to these defenses despite known deleterious effects of contaminants on animal inducible defenses. Here, we investigated the effect of copper contamination on the interactions between a snail herbivore and a brown seaweed that displays inducible resistance to grazing. We examined seaweed inducible resistance and its effectiveness for organisms exposed to copper at two time points, either during induction or after herbivores had already induced seaweed defenses. Under ambient conditions, non-grazed tissues were more palatable than grazed tissues. However, copper additions negated the preference for non-grazed tissues regardless of the timing of copper exposure, suggesting that copper decreased both how herbivores initiated these inducible defenses and their subsequent effectiveness. Copper decreased stimulation of defenses, at least in part, by suppressing snail grazing pressure-the cue that turns inducible defenses on. Copper decreased effectiveness of defenses by preventing snails from preferentially consuming non-grazed seaweed. Thus, contaminants can potentially stress communities by changing seaweed-herbivore interactions mediated via inducible defenses. Given the ubiquity of seaweed inducible resistance and their potential influence on herbivores, we hypothesize that copper contamination may change the impact of these resistant traits on herbivores.


Assuntos
Cobre/efeitos adversos , Herbivoria , Água do Mar/química , Alga Marinha/metabolismo , Caramujos/metabolismo , Poluição Química da Água/efeitos adversos , Animais
19.
PLoS One ; 10(7): e0133329, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26172044

RESUMO

Although the cascading impact of predators depends critically on the relative role of lethal predation and predation risk, we lack an understanding of how human-caused stressors may shift this balance. Emergent evidence suggests that pollution may increase the importance of predator consumptive effects by weakening the effects of fear perceived by prey. However, this oversimplification ignores the possibility that pollution may also alter predator consumptive effects. In particular, contaminants may impair the consumptive effects of predators by altering density-dependent interactions among prey conspecifics. No study has directly compared predator consumptive and non-consumptive effects in polluted versus non-polluted settings. We addressed this issue by using laboratory mesocosms to examine the impact of sublethal doses of copper on tri-trophic interactions among estuarine predator crabs Cancer productus, carnivorous whelk prey Urosalpinx cinerea, and the basal resource barnacles Balanus glandula. We investigated crab consumptive effects (whelks culled without crab chemical cues), non-consumptive effects (whelks not culled with crab chemical cues), and total effects (whelks culled with crab chemical cues) on whelks in copper polluted and non-polluted waters. Realistic copper concentrations suppressed the effects of simulated crab lethal predation (whelk culling) by removing density-dependent feeding by whelks. Specifically, reductions in conspecific density occurring in elevated copper levels did not trigger the normal increase in whelk consumption rates of barnacles. Weakened effects of fear were only observed at extremely high copper levels, suggesting consumptive effects were more sensitive to pollution. Thus, pollution may shape communities by altering the roles of predators and interactions among prey.


Assuntos
Cobre/efeitos adversos , Poluição Ambiental/efeitos adversos , Comportamento Predatório/efeitos dos fármacos , Animais , Braquiúros/efeitos dos fármacos , Sinais (Psicologia) , Cadeia Alimentar , Gastrópodes/efeitos dos fármacos , Risco , Thoracica/efeitos dos fármacos
20.
Artigo em Inglês | MEDLINE | ID: mdl-25802538

RESUMO

Biologically active CAM may detrimentally interfere with chemotherapy treatment, so cancer patients require targeted, evidence-based information on chemotherapy-CAM integration consequences. The object of this study was to investigate the potential for medical doctor recommendation and patient acceptance of a purpose-designed patient educational brochure on the safe use of CAM with chemotherapy. Cancer care doctors (n = 17) were provided a draft version of a patient educational brochure developed by the authors and completed a structured feedback form. Cancer patients receiving treatment (n = 12) were provided with the brochure and completed the local health service consumer testing feedback form. All 17 doctors perceived a need for the brochure and all would recommend the brochure to their patients. Approximately 59% of the doctors indicated they would recommend the brochure to all patients receiving chemotherapy and 41% preferred that only patients using CAM or who enquired about CAM be given the brochure. Cancer patients receiving chemotherapy reported that the brochure information answered their questions and was easy to understand. This evidence-based CAM-chemotherapy patient brochure may be a useful adjunct for use by cancer care health professionals to educate patients on the potential dangers of biologically active CAM use with chemotherapy and to provide patients with safe CAM alternatives.

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