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1.
J Exp Biol ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39054929

RESUMO

Wolbachia is a widespread maternally-transmitted endosymbiotic bacteria with diverse phenotypic effects on its insect hosts, ranging from parasitic to mutualistic. Wolbachia commonly infects social insects, where it faces unique challenges associated with its hosts' caste-based reproductive division of labor and colony living. Here we dissect the benefits and costs of Wolbachia infection on life-history traits of the invasive pharaoh ant, Monomorium pharaonis, which are relatively short-lived and show natural variation in Wolbachia infection status between colonies. We quantified effects of Wolbachia infection on the lifespan of queen and worker castes, the egg-laying rate of queens across queen lifespan, and the metabolic rates of whole colonies and colony members. Infected queens laid more eggs than uninfected queens but had similar metabolic rates and lifespans. Interestingly, infected workers outlived uninfected workers. At the colony level, infected colonies were more productive due to increased queen egg-laying rates and worker longevity, and infected colonies had higher metabolic rates during peak colony productivity. While some effects of infection, such as elevated colony-level metabolic rates may be detrimental in more stressful natural conditions, we did not find any costs of infection under relatively benign laboratory conditions. Overall, our study emphasizes that Wolbachia infection can have beneficial effects on ant colony growth and worker survival in at least some environments.

2.
Integr Comp Biol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982327

RESUMO

The evolution of flight in an early winged insect ancestral lineage is recognized as a key adaptation explaining the unparalleled success and diversification of insects. Subsequent transitions and modifications to flight machinery, including secondary reductions and losses, also play a central role in shaping the impacts of insects on broadscale geographic and ecological processes and patterns in the present and future. Given the importance of insect flight, there has been a centuries-long history of research and debate on the evolutionary origins and biological mechanisms of flight. Here, we revisit this history from an interdisciplinary perspective, discussing recent discoveries regarding the developmental origins, physiology, biomechanics, and neurobiology and sensory control of flight in a diverse set of insect models. We also identify major outstanding questions yet to be addressed and provide recommendations for overcoming current methodological challenges faced when studying insect flight, which will allow the field to continue to move forward in new and exciting directions. By integrating mechanistic work into ecological and evolutionary contexts, we hope that this synthesis promotes and stimulates new interdisciplinary research efforts necessary to close the many existing gaps about the causes and consequences of insect flight evolution.

3.
ACS Nano ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017620

RESUMO

Better techniques for imaging ferroelectric polarization would aid the development of new ferroelectrics and the refinement of old ones. Here we show how scanning transmission electron microscope (STEM) electron beam-induced current (EBIC) imaging reveals ferroelectric polarization with obvious, simply interpretable contrast. Planar imaging of an entire ferroelectric hafnium zirconium oxide (Hf0.5Zr0.5O2, HZO) capacitor shows an EBIC response that is linearly related to the polarization determined in situ with the positive-up, negative-down (PUND) method. The contrast is easily calibrated in MV/cm. The underlying mechanism is magnification-independent, operating equally well on micrometer-sized devices and individual nanoscale domains. Coercive-field mapping reveals that individual domains are biased "positive" and "negative", as opposed to being "easy" and "hard" to switch. The remanent background E-fields generating this bias can be isolated and mapped. Coupled with STEM's native capabilities for structural identification, STEM EBIC imaging provides a revolutionary tool for characterizing ferroelectric materials and devices.

5.
Sleep Med Rev ; 76: 101950, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38788520

RESUMO

Sleep disturbances are common, affecting over half of adults with a mental disorder. For those admitted to a psychiatric ward, difficulties with sleep, particularly insomnia, are compounded by factors relating to the inpatient setting. We conducted a scoping review of sleep intervention studies involving adults admitted to psychiatric settings. We categorised the different types of sleep interventions and identified the effects on sleep and other mental and physical health outcomes. Instruments used to measure sleep were also examined. The search strategy yielded 4780 studies, of which 28 met the inclusion criteria. There was evidence of more non-pharmacological than pharmacological interventions having been tested in inpatient settings. Results indicated that non-pharmacological interventions based on cognitive behaviour therapy for insomnia improve sleep and may improve mental and physical health. Several distinct sleep measures were used in the studies. Gaps in the literature were identified, highlighting the importance of research into a wider range of sleep interventions tested against robust controls, using validated measures of sleep with evaluation of additional mental and physical health outcomes among a large sample size of adults in the psychiatric inpatient settings.


Assuntos
Pacientes Internados , Transtornos Mentais , Humanos , Transtornos Mentais/terapia , Terapia Cognitivo-Comportamental/métodos , Distúrbios do Início e da Manutenção do Sono/terapia , Adulto , Transtornos do Sono-Vigília/terapia
6.
BMC Med Ethics ; 25(1): 54, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745276

RESUMO

BACKGROUND: A morally sound framework for benefit-sharing is crucial to minimize research exploitation for research conducted in developing countries. However, in practice, it remains uncertain which stakeholders should be involved in the decision-making process regarding benefit-sharing and what the implications might be. Therefore the study aimed to empirically propose a framework for benefit-sharing negotiations in research by taking HIV vaccine trials as a case. METHODS: The study was conducted in Tanzania using a case study design and qualitative approaches. Data were collected using in-depth interviews (IDI) and focus group discussions (FGD). A total of 37 study participants were selected purposively comprising institutional review board (IRB) members, researchers, community advisory board (CAB) members, a policymaker, and HIV/AIDS advocates. Deductive and inductive thematic analysis approaches were deployed to analyze collected data with the aid of MAXQDA version 20.4.0 software. RESULTS: The findings indicate a triangular relationship between the research community, researched community and intermediaries. However, the relationship ought to take into consideration the timing of negotiations, the level of understanding between parties and the phase of the clinical trial. The proposed framework operationalize partnership interactions in community-based participatory research. CONCLUSION: In the context of this study, the suggested framework incorporates the research community, the community being researched, and intermediary parties. The framework would guarantee well-informed and inclusive decision-making regarding benefit-sharing in HIV vaccine trials and other health-related research conducted in resource-limited settings.


Assuntos
Vacinas contra a AIDS , Pesquisa Participativa Baseada na Comunidade , Infecções por HIV , Negociação , Pesquisa Qualitativa , Humanos , Vacinas contra a AIDS/administração & dosagem , Infecções por HIV/prevenção & controle , Tanzânia , Ensaios Clínicos como Assunto , Grupos Focais , Masculino , Feminino , Tomada de Decisões , Pesquisadores , Participação dos Interessados , Países em Desenvolvimento , Adulto
7.
J Clin Ethics ; 35(2): 93-100, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728693

RESUMO

AbstractObjective: We performed this study to examine patients' choices to permit or refuse medical student pelvic examinations under anesthesia (EUAs) during planned gynecologic procedures. DESIGN: We conducted an exploratory retrospective chart review of electronic consent forms at a single academic medical center using contingency tables, logistic regression, and nonparametric tests to explore relationships between patient and physician characteristics and consent. RESULTS: We identified and downloaded electronic consent forms for a census of 4,000 patients undergoing gynecologic surgery from September 2020 through calendar year 2022. Forms were linked to anonymized medical record information. Of the 4,000 patients, 142 (3.6%) were removed from analysis because consent forms were incomplete. Of 3,858 patients, 308 (8.0%) were asked for EUA consent more than once, 46 of whom were not consistent. Overall, 3,308 (85.7%) patients consented every time asked, and 550 (14.2%) refused or limited EUA consent at least once. Nine patients limited their consent to female students, and two patients refused medical student participation at all. We performed exploratory multiple logistic regression analyses exploring differences in rates of consent across patient and physician demographic groups. CONCLUSIONS: We find that some patients are more likely than others to refuse a pelvic EUA, magnifying the dignitary harm from a nonconsensual invasion of intimate bodily integrity and perpetuating historic wrongs visited upon vulnerable people of color and religious minorities. Patients' rights to respect and control over their bodies require that physicians take seriously the ethical obligation to inform their patients and ask them for permission.


Assuntos
Exame Ginecológico , Consentimento Livre e Esclarecido , Estudantes de Medicina , Humanos , Feminino , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Anestesia/ética , Masculino , Procedimentos Cirúrgicos em Ginecologia , Idoso
8.
Proc Biol Sci ; 291(2023): 20240424, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38807520

RESUMO

Many theoretical treatments of foraging use energy as currency, with carbohydrates and lipids considered interchangeable as energy sources. However, herbivores must often synthesize lipids from carbohydrates since they are in short supply in plants, theoretically increasing the cost of growth. We tested whether a generalist insect herbivore (Locusta migratoria) can improve its growth efficiency by consuming lipids, and whether these locusts have a preferred caloric intake ratio of carbohydrate to lipid (C : L). Locusts fed pairs of isocaloric, isoprotein diets differing in C and L consistently selected a 2C : 1L target. Locusts reared on isocaloric, isoprotein 3C : 0L diets attained similar final body masses and lipid contents to locusts fed the 2C : 1L diet, but they ate more and had a ~12% higher metabolic rate, indicating an energetic cost for lipogenesis. These results demonstrate that some animals can selectively regulate carbohydrate-to-lipid intake and that consumption of dietary lipids can improve growth efficiency.


Assuntos
Carboidratos da Dieta , Gafanhotos , Animais , Gafanhotos/fisiologia , Gafanhotos/crescimento & desenvolvimento , Gorduras na Dieta , Dieta/veterinária , Metabolismo Energético , Metabolismo dos Lipídeos , Ingestão de Energia , Herbivoria
9.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559183

RESUMO

Circulating Tumor Cells (CTCs), interrogated by sampling blood from patients with cancer, contain multiple analytes, including intact RNA, high molecular weight DNA, proteins, and metabolic markers. However, the clinical utility of tumor cell-based liquid biopsy has been limited since CTCs are very rare, and current technologies cannot process the blood volumes required to isolate a sufficient number of tumor cells for in-depth assays. We previously described a high-throughput microfluidic prototype utilizing high-flow channels and amplification of cell sorting forces through magnetic lenses. Here, we apply this technology to analyze patient-derived leukapheresis products, interrogating a mean blood volume of 5.83 liters from patients with metastatic cancer, with a median of 2,799 CTCs purified per patient. Isolation of many CTCs from individual patients enables characterization of their morphological and molecular heterogeneity, including cell and nuclear size and RNA expression. It also allows robust detection of gene copy number variation, a definitive cancer marker with potential diagnostic applications. High-volume microfluidic enrichment of CTCs constitutes a new dimension in liquid biopsies.

11.
Ethics Hum Res ; 46(3): 26-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629224

RESUMO

We performed a qualitative review of 50 consent forms posted on Clinicaltrials.gov, examining the content of key information sections. We found that key information disclosures are typically focused on procedures, risks, potential benefits, and alternatives. Drawing upon reviews of the large literature examining the reasons people do or do not take part in research, we propose that these disclosures should be based more directly on what we know to be the real reasons why people choose to take part or refuse participation. We propose key information language for consideration by researchers and institutional review boards.


Assuntos
Termos de Consentimento , Consentimento Livre e Esclarecido , Humanos , Revelação , Comitês de Ética em Pesquisa , Pesquisadores , Ensaios Clínicos como Assunto
12.
Am J Obstet Gynecol ; 231(1): 130.e1-130.e10, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38527602

RESUMO

BACKGROUND: Assessing the umbilical artery pulsatility index via Doppler measurements plays a crucial role in evaluating fetal growth impairment. OBJECTIVE: This study aimed to investigate perinatal outcomes associated with discordant pulsatility indices of umbilical arteries in fetuses with growth restriction. STUDY DESIGN: In this retrospective cohort study, all singleton pregnancies were included if their estimated fetal weight and/or abdominal circumference fell below the 10th percentile for gestational age (2017-2022). Eligible cases included singleton pregnancies with concurrent sampling of both umbilical arteries within 14 days of birth at the ultrasound evaluation closest to delivery. The exclusion criteria included births before 22 weeks of gestation, evidence of absent or reverse end-diastolic flow in either umbilical artery, and known fetal genetic or structural anomalies. The study compared cases with discordant umbilical artery pulsatility index values (defined as 1 umbilical artery pulsatility index at ≤95th percentile and the other umbilical artery pulsatility index at >95th percentile for gestational age) to pregnancies where both umbilical artery pulsatility indices had normal pulsatility index values and those with both umbilical arteries displaying abnormal pulsatility index values. The primary outcome assessed was the occurrence of composite adverse neonatal outcomes. Multivariable logistic regressions were performed, adjusting for relevant covariates. RESULTS: The study encompassed 1014 patients, including 194 patients (19.1%) with discordant umbilical artery pulsatility index values among those who had both umbilical arteries sampled close to delivery, 671 patients (66.2%) with both umbilical arteries having normal pulsatility index values, and 149 patients (14.7%) with both umbilical arteries exhibiting abnormal values. Pregnancies with discordant umbilical artery pulsatility index values displayed compromised sonographic parameters compared with those with both umbilical arteries showing normal pulsatility index values. Similarly, the number of abnormal umbilical artery pulsatility index values was associated with adverse perinatal outcomes in a dose-response manner. Cases with 1 abnormal (discordant) umbilical artery pulsatility index value showed favorable sonographic parameters and perinatal outcomes compared with cases with both abnormal umbilical artery pulsatility index values, and cases with both abnormal umbilical artery pulsatility index values showed worse sonographic parameters and perinatal outcomes compared with cases with discordant UA PI values. Multivariate analysis revealed that discordant umbilical artery pulsatility indices were significantly and independently associated with composite adverse perinatal outcomes, with an adjusted odds ratio of 1.75 (95% confidence interval, 1.24-2.47; P = .002). CONCLUSION: Evaluating the resistance indices of both umbilical arteries may provide useful data and assist in assessing adverse perinatal outcomes among fetuses with growth restriction.


Assuntos
Retardo do Crescimento Fetal , Fluxo Pulsátil , Ultrassonografia Pré-Natal , Artérias Umbilicais , Humanos , Feminino , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/fisiopatologia , Gravidez , Retardo do Crescimento Fetal/fisiopatologia , Retardo do Crescimento Fetal/diagnóstico por imagem , Estudos Retrospectivos , Adulto , Resistência Vascular , Recém-Nascido , Ultrassonografia Doppler , Resultado da Gravidez , Idade Gestacional , Estudos de Coortes
13.
J Exp Biol ; 227(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38487901

RESUMO

While multiple studies have shown that honey bees and some other flying insects lower their flight metabolic rates when flying at high air temperatures, critics have suggested such patterns result from poor experimental methods as, theoretically, air temperature should not appreciably affect aerodynamic force requirements. Here, we show that apparently contradictory studies can be reconciled by considering the thermal performance curve of flight muscle. We show that prior studies that found no effects of air temperature on flight metabolism of honey bees achieved flight muscle temperatures that were near or on equal, opposite sides of the thermal performance curve. Honey bees vary their wing kinematics and metabolic heat production to thermoregulate, and how air temperature affects the flight metabolic rate of honey bees is predictable using a non-linear thermal performance perspective of honey bee flight muscle.


Assuntos
Voo Animal , Insetos , Abelhas , Animais , Temperatura , Voo Animal/fisiologia , Metabolismo Energético/fisiologia , Músculos/metabolismo
14.
J Obstet Gynaecol Can ; 46(2): 102410, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38442955
15.
Proc Biol Sci ; 291(2019): 20240040, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38531398

RESUMO

Interactions between environmental stressors may contribute to ongoing pollinator declines, but have not been extensively studied. Here, we examined the interaction between the agricultural fungicide Pristine (active ingredients: 25.2% boscalid, 12.8% pyraclostrobin) and high temperatures on critical honeybee behaviours. We have previously shown that consumption of field-realistic levels of this fungicide shortens worker lifespan in the field and impairs associative learning performance in a laboratory-based assay. We hypothesized that Pristine would also impair homing and foraging behaviours in the field, and that an interaction with hot weather would exacerbate this effect. Both field-relevant Pristine exposure and higher air temperatures reduced the probability of successful return on their own. Together, the two factors synergistically reduced the probability of return and increased the time required for bees to return to the hive. Pristine did not affect the masses of pollen or volumes of nectar or water brought back to the hive by foragers, and it did not affect the ratio of forager types in a colony. However, Pristine-fed bees brought more concentrated nectar back to the hive. As both agrochemical usage and heat waves increase, additive and synergistic negative effects may pose major threats to pollinators and sustainable agriculture.


Assuntos
Fungicidas Industriais , Abelhas , Animais , Néctar de Plantas , Comportamento de Retorno ao Território Vital , Temperatura , Condicionamento Clássico
16.
Res Sq ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38313253

RESUMO

Sleep and circadian rhythm disruptions are comorbid features of many pathologies and can negatively influence numerous health conditions, including degenerative diseases, metabolic illnesses, cancer, and various neurological disorders. Genetic association studies linking sleep and circadian disturbances with disease susceptibility have mainly focused on changes in gene expression due to mutations, such as single-nucleotide polymorphisms. Thus, associations between sleep and/or circadian rhythm and alternative polyadenylation (APA), particularly in the context of other health challenges, are largely undescribed. APA is a process that generates various transcript isoforms from the same gene, resulting in effects on mRNA translation, stability, localization, and subsequent function. Here, we have identified unique APAs in rat brain that exhibit time-of-day-dependent oscillations in expression as well as APAs that are altered by sleep deprivation and the subsequent recovery period. Genes affected by APA usage include Mapt/Tau, Ntrk2, Homer1A, Sin3band Sorl. Sorl1 has two APAs which cycle with a 24 h period, one additional APA cycles with a 12 h period and one more that is reduced during recovery sleep. Finally, we compared sleep- or circadian-associated APAs with recently described APA-linked brain disorder susceptibility genes and found 46 genes in common.

17.
Proc Natl Acad Sci U S A ; 121(4): e2311025121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38227669

RESUMO

Heat waves are becoming increasingly common due to climate change, making it crucial to identify and understand the capacities for insect pollinators, such as honey bees, to avoid overheating. We examined the effects of hot, dry air temperatures on the physiological and behavioral mechanisms that honey bees use to fly when carrying nectar loads, to assess how foraging is limited by overheating or desiccation. We found that flight muscle temperatures increased linearly with load mass at air temperatures of 20 or 30 °C, but, remarkably, there was no change with increasing nectar loads at an air temperature of 40 °C. Flying, nectar-loaded bees were able to avoid overheating at 40 °C by reducing their flight metabolic rates and increasing evaporative cooling. At high body temperatures, bees apparently increase flight efficiency by lowering their wingbeat frequency and increasing stroke amplitude to compensate, reducing the need for evaporative cooling. However, even with reductions in metabolic heat production, desiccation likely limits foraging at temperatures well below bees' critical thermal maxima in hot, dry conditions.


Assuntos
Néctar de Plantas , Termotolerância , Abelhas , Animais , Água , Temperatura Corporal , Termogênese
18.
Sci Rep ; 14(1): 788, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191782

RESUMO

Geological disposal of radioactive waste is being planned by many countries. Bentonite clay is often included in facility design, providing a barrier to radionuclide migration. Gas, generated by the waste or corrosion of waste canisters, may disrupt the properties of the bentonite. Robust prediction of this interaction is, therefore, necessary to demonstrate safe facility evolution. In some cases, gas may deform the clay, resulting in localised flow; however, the nature of this deformation has been widely debated. Accurate numerical representation of this behaviour has been limited by a shortage of information on the degree/distribution of deformation. Using experimental data from gas injection tests in bentonite, we show that first order fluctuations in the stress field can provide this information. We show that hundreds of microdeformation events can be detected, with similar characteristics to established fracturing phenomena, including earthquakes and acoustic emissions. We also demonstrate that stress field disruption (i) is spatially localised and (ii) has characteristics consistent with gas pathway 'opening' and 'closure' as gas enters and exits the clay, respectively. This new methodology offers fundamental insight and a new opportunity to parameterise and constrain gas advection models in clays and shales, substantially improving our capacity for safe facility design.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37703163

RESUMO

As ferroelectric hafnium zirconium oxide (HZO) becomes more widely utilized in ferroelectric microelectronics, integration impacts of intentional and nonintentional dielectric interfaces and their effects upon the ferroelectric film wake-up (WU) and circuit parameters become important to understand. In this work, the effect of the addition of a linear dielectric aluminum oxide, Al2O3, below a ferroelectric Hf0.58Zr0.42O2 film in a capacitor structure for FeRAM applications with niobium nitride (NbN) electrodes was measured. Depolarization fields resulting from the linear dielectric is observed to induce a reduction of the remanent polarization of the ferroelectric. Addition of the aluminum oxide also impacts the WU of the HZO with respect to the cycling voltage applied. Intricately linked to the design of a FeRAM 1C/1T cell, the metal-ferroelectric-insulator-metal (MFIM) devices are observed to significantly shift charge related to the read states based on aluminum oxide thickness and WU cycling voltage. A 33% reduction in the separation of read states are measured, which complicates how a memory cell is designed and illustrates the importance of clean interfaces in devices.

20.
Transfus Clin Biol ; 31(1): 56, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096949
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