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1.
Physiol Genomics ; 55(4): 194-212, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36939205

RESUMEN

Acute exercise elicits dynamic transcriptional changes that, when repeated, form the fundamental basis of health, resilience, and performance adaptations. While moderate-intensity endurance training combined with conventional resistance training (traditional, TRAD) is often prescribed and recommended by public health guidance, high-intensity training combining maximal-effort intervals with intensive, limited-rest resistance training is a time-efficient alternative that may be used tactically (HITT) to confer similar benefits. Mechanisms of action of these distinct stimuli are incompletely characterized and have not been directly compared. We assessed transcriptome-wide responses in skeletal muscle and circulating extracellular vesicles (EVs) to a single exercise bout in young adults randomized to TRAD (n = 21, 12 M/9 F, 22 ± 3 yr) or HITT (n = 19, 11 M/8 F, 22 ± 2 yr). Next-generation sequencing captured small, long, and circular RNA in muscle and EVs. Analysis identified differentially expressed transcripts (|log2FC|>1, FDR ≤ 0.05) immediately (h0, EVs only), h3, and h24 postexercise within and between exercise protocols. In aaddition, all apparently responsive transcripts (FDR < 0.2) underwent singular value decomposition to summarize data structures into latent variables (LVs) to deconvolve molecular expression circuits and interregulatory relationships. LVs were compared across time and exercise protocol. TRAD, a longer but less intense stimulus, generally elicited a stronger transcriptional response than HITT, but considerable overlap and key differences existed. Findings reveal shared and unique molecular responses to the exercise stimuli and lay groundwork toward establishing relationships between protein-coding genes and lesser-understood transcripts that serve regulatory roles following exercise. Future work should advance the understanding of these circuits and whether they repeat in other populations or following other types of exercise/stress.NEW & NOTEWORTHY We examined small and long transcriptomics in skeletal muscle and serum-derived extracellular vesicles before and after a single exposure to traditional combined exercise (TRAD) and high-intensity tactical training (HITT). Across 40 young adults, we found more consistent protein-coding gene responses to TRAD, whereas HITT elicited differential expression of microRNA enriched in brain regions. Follow-up analysis revealed relationships and temporal dynamics across transcript networks, highlighting potential avenues for research into mechanisms of exercise response and adaptation.


Asunto(s)
Entrenamiento de Fuerza , Transcriptoma , Humanos , Adulto Joven , Transcriptoma/genética , Ejercicio Físico/fisiología , Perfilación de la Expresión Génica , Músculo Esquelético/metabolismo
2.
New Phytol ; 238(3): 1263-1277, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36721257

RESUMEN

The adaptation of weeds to herbicide is both a significant problem in agriculture and a model of rapid adaptation. However, significant gaps remain in our knowledge of resistance controlled by many loci and the evolutionary factors that influence the maintenance of resistance. Here, using herbicide-resistant populations of the common morning glory (Ipomoea purpurea), we perform a multilevel analysis of the genome and transcriptome to uncover putative loci involved in nontarget-site herbicide resistance (NTSR) and to examine evolutionary forces underlying the maintenance of resistance in natural populations. We found loci involved in herbicide detoxification and stress sensing to be under selection and confirmed that detoxification is responsible for glyphosate (RoundUp) resistance using a functional assay. We identified interchromosomal linkage disequilibrium (ILD) among loci under selection reflecting either historical processes or additive effects leading to the resistance phenotype. We further identified potential fitness cost loci that were strongly linked to resistance alleles, indicating the role of genetic hitchhiking in maintaining the cost. Overall, our work suggests that NTSR glyphosate resistance in I. purpurea is conferred by multiple genes which are potentially maintained through generations via ILD, and that the fitness cost associated with resistance in this species is likely a by-product of genetic hitchhiking.


Asunto(s)
Herbicidas , Ipomoea , Resistencia a los Herbicidas/genética , Desequilibrio de Ligamiento/genética , Evolución Biológica , Herbicidas/farmacología , Ipomoea/genética
3.
Pain Med ; 24(9): 1058-1065, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37084261

RESUMEN

OBJECTIVE: Compare intrathecal oxytocin, 100 µg to placebo on ongoing neuropathic pain and mechanical hyperalgesia and allodynia. STUDY DESIGN: Randomized, controlled, double-blind cross-over. SETTING: Clinical research unit. SUBJECTS: Individuals aged 18 to 70 years with neuropathic pain for at least 6 months. METHODS: Individuals received intrathecal injections of oxytocin and saline, separated by at least 7 days, and ongoing pain in neuropathic area (VAS [visual analog scale]) and areas of hypersensitivity to von Frey filament and cotton wisp brushing were measured for 4 hours. Primary outcome was VAS pain in the first 4 hours after injection, analyzed by linear mixed effects model. Secondary outcomes were verbal pain intensity scores at daily intervals for 7 days and areas of hypersensitivity and elicited pain for 4 hours after injections. RESULTS: The study was stopped early after completion of 5 of 40 subjects planned due to slow recruitment and funding limitations. Pain intensity prior to injection was 4.75 ± 0.99 and modeled pain intensity decreased more after oxytocin than placebo to 1.61 ± 0.87 and 2.49 ± 0.87, respectively (P = .003). Daily pain scores were lower in the week following injection of oxytocin than saline (2.53 ± 0.89 vs 3.66 ± 0.89; P = .001). Allodynic area decreased by 11%, but hyperalgesic area increased by 18% after oxytocin compared to placebo. There were no study drug related adverse effects. CONCLUSION: Although limited by the small number of subjects studied, oxytocin reduced pain more than placebo in all subjects. Further study of spinal oxytocin in this population is warranted. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov on 03/27/2014 (NCT02100956). The first subject was studied on 06/25/2014.


Asunto(s)
Neuralgia , Oxitocina , Humanos , Oxitocina/uso terapéutico , Estudios Cruzados , Neuralgia/tratamiento farmacológico , Hiperalgesia/tratamiento farmacológico , Dimensión del Dolor , Método Doble Ciego
4.
PLoS Genet ; 16(2): e1008593, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32012153

RESUMEN

The repeated evolution of herbicide resistance has been cited as an example of genetic parallelism, wherein separate species or genetic lineages utilize the same genetic solution in response to selection. However, most studies that investigate the genetic basis of herbicide resistance examine the potential for changes in the protein targeted by the herbicide rather than considering genome-wide changes. We used a population genomics screen and targeted exome re-sequencing to uncover the potential genetic basis of glyphosate resistance in the common morning glory, Ipomoea purpurea, and to determine if genetic parallelism underlies the repeated evolution of resistance across replicate resistant populations. We found no evidence for changes in 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), glyphosate's target protein, that were associated with resistance, and instead identified five genomic regions that showed evidence of selection. Within these regions, genes involved in herbicide detoxification-cytochrome P450s, ABC transporters, and glycosyltransferases-are enriched and exhibit signs of selective sweeps. One region under selection shows parallel changes across all assayed resistant populations whereas other regions exhibit signs of divergence. Thus, while it appears that the physiological mechanism of resistance in this species is likely the same among resistant populations, we find patterns of both similar and divergent selection across separate resistant populations at particular loci.


Asunto(s)
Genoma de Planta/genética , Glicina/análogos & derivados , Herbicidas/farmacología , Ipomoea/genética , Malezas/genética , 3-Fosfoshikimato 1-Carboxiviniltransferasa/antagonistas & inhibidores , 3-Fosfoshikimato 1-Carboxiviniltransferasa/genética , ADN de Plantas/genética , ADN de Plantas/aislamiento & purificación , Evolución Molecular , Exoma/genética , Glicina/farmacología , Resistencia a los Herbicidas/genética , Ipomoea/efectos de los fármacos , Proteínas de Plantas/antagonistas & inhibidores , Proteínas de Plantas/genética , Malezas/efectos de los fármacos , Semillas/efectos de los fármacos , Semillas/genética , Selección Genética , Análisis de Secuencia de ADN , Glifosato
5.
Sensors (Basel) ; 24(1)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38202933

RESUMEN

Space systems play an integral role in every facet of our daily lives, including national security, communications, and resource management. Therefore, it is critical to protect our valuable assets in space and build resiliency in the space environment. In recent years, we have developed a novel approach to Space Situational Awareness (SSA), in the form of a low-resolution, Wide Field-of-View (WFOV) camera payload for attitude determination and Resident Space Object (RSO) detection. Detection is the first step in tracking, identification, and characterization of RSOs, including natural and artificial objects orbiting the Earth. A space-based dual-purpose camera that can provide attitude information alongside RSO detection can enhance the current SSA technologies which rely on ground infrastructure. A CubeSat form factor payload with real-time attitude determination and RSO detection algorithms was developed and flown onboard the CSA/CNES stratospheric balloon platform in August 2023. Sub-degree pointing information and multiple RSO detections were demonstrated during operation, with opportunities for improvement discussed. This paper outlines the hardware and software architecture, system design methodology, on-ground testing, and in-flight results of the dual-purpose camera payload.

6.
Sensors (Basel) ; 23(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38139514

RESUMEN

In recent years, there has been a significant increase in satellite launches, resulting in a proliferation of satellites in our near-Earth space environment. This surge has led to a multitude of resident space objects (RSOs). Thus, detecting RSOs is a crucial element of monitoring these objects and plays an important role in preventing collisions between them. Optical images captured from spacecraft and with ground-based telescopes provide valuable information for RSO detection and identification, thereby enhancing space situational awareness (SSA). However, datasets are not publicly available due to their sensitive nature. This scarcity of data has hindered the development of detection algorithms. In this paper, we present annotated RSO images, which constitute an internally curated dataset obtained from a low-resolution wide-field-of-view imager on a stratospheric balloon. In addition, we examine several frame differencing techniques, namely, adjacent frame differencing, median frame differencing, proximity filtering and tracking, and a streak detection method. These algorithms were applied to annotated images to detect RSOs. The proposed algorithms achieved a competitive degree of success with precision scores of 73%, 95%, 95%, and 100% and F1 scores of 68%, 77%, 82%, and 79%.

7.
Sensors (Basel) ; 23(14)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37514889

RESUMEN

Space situational awareness (SSA) refers to collecting, analyzing, and keeping track of detailed knowledge of resident space objects (RSOs) in the space environment. With the rapidly increasing number of objects in space, the need for SSA grows as well. Traditional methods rely heavily on imaging RSOs from large, narrow field-of-view (FOV), ground-based telescopes. This research outlines the technology demonstration payload, Resident Space Object Near-space Astrometric Research (RSONAR)-a star tracker-like, wide FOV camera combined with commercial off-the-shelf (COTS) hardware to image RSOs from the stratosphere, overcoming the disadvantages of ground-based observations. The hardware components and software algorithm are described and evaluated. The eligibility of the payload for SSA is proven by the image processing algorithms, which detect the RSOs in the images captured during flight and the survival of the COTS components in the near-space environment. The payload features a low-resolution, wide FOV camera coupled with a Field Programmable Gate Array (FPGA)-based platform that houses the altitude and time-based image capture algorithm. The newly developed payload in a 2U-CubeSat form factor was flown as a space-ready payload on the CSA/CNES stratospheric balloon research platform to carry out algorithm and functionality tests in August 2022.

8.
Nurs Inq ; 30(4): e12578, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37401504

RESUMEN

This study aimed to understand the expressions of fear in the journeys of health professionals who worked in the confrontation of coronavirus disease 2019 (COVID-19), in the city of Manaus, in the Brazilian Western Amazon. This is an exploratory qualitative study that adopts interpretive description as a method to generate informed knowledge responsive to the needs of the practice. We included 56 participants, comprising 23 health managers and 33 health workers (middle and higher level) of different professional categories. The results revealed three circles of experience: (1) knowledge and professional experience in dealing with the disease (unknown-known-experienced); (2) the growing proximity to death and loss (predicted-witnessed-suffered); and (3) the involvement and proximity to whatever affects the individual, their emotions, and personal transformations in the face of the threat (the collective, the neighbor, and oneself). Our results suggest that health professionals who worked during the COVID-19 pandemic in Manaus experienced insecurity, dread, and fear, illustrating the complexity of developing their activities in the front line of care and management during the different phases of the pandemic. A contribution of the study is precisely that of capturing this complexity, which suggests the impossibility of analyzing fear only in its simple manifestation, or in each circle of experience.

9.
Ann Bot ; 130(7): 1015-1028, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36415945

RESUMEN

BACKGROUND AND AIMS: When plant communities are exposed to herbicide 'drift', wherein particles containing the active ingredient travel off-target, interspecific variation in resistance or tolerance may scale up to affect community dynamics. In turn, these alterations could threaten the diversity and stability of agro-ecosystems. We investigated the effects of herbicide drift on the growth and reproduction of 25 wild plant species to make predictions about the consequences of drift exposure on plant-plant interactions and the broader ecological community. METHODS: We exposed potted plants from species that commonly occur in agricultural areas to a drift-level dose of the widely used herbicide dicamba or a control solution in the glasshouse. We evaluated species-level variation in resistance and tolerance for vegetative and floral traits. We assessed community-level impacts of drift by comparing the species evenness and flowering networks of glasshouse synthetic communities comprised of drift-exposed and control plants. KEY RESULTS: Species varied significantly in resistance and tolerance to dicamba drift: some were negatively impacted while others showed overcompensatory responses. Species also differed in the way they deployed flowers over time following drift exposure. While drift had negligible effects on community evenness based on vegetative biomass, it caused salient differences in the structure of co-flowering networks within communities. Drift reduced the degree and intensity of flowering overlap among species, altered the composition of groups of species that were more likely to co-flower with each other than with others and shifted species roles (e.g. from dominant to inferior floral producers, and vice versa). CONCLUSIONS: These results demonstrate that even low levels of herbicide exposure can significantly alter plant growth and reproduction, particularly flowering phenology. If field-grown plants respond similarly, then these changes would probably impact plant-plant competitive dynamics and potentially plant-pollinator interactions occurring within plant communities at the agro-ecological interface.


Asunto(s)
Herbicidas , Herbicidas/toxicidad , Dicamba/farmacología , Ecosistema , Reproducción , Plantas , Flores/fisiología , Polinización
10.
J Nurs Adm ; 52(11): 577-583, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36301868

RESUMEN

Strategic plans provide a roadmap for value creation by outlining key priorities that, when executed successfully, enhance quality and efficiency. Nurses are uniquely positioned to inform strategic planning because of their understanding of clinical operations and consumer needs. This article describes a multiphase process for engaging nurses, at all levels, in developing, implementing, and revising a nursing strategic plan over a 5-year period.


Asunto(s)
Planificación Estratégica , Humanos , Objetivos Organizacionales
11.
Sensors (Basel) ; 22(15)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35957245

RESUMEN

A catalogue of over 22,000 objects in Earth's orbit is currently maintained, and that number is expected to double within the next decade. Novel data collection regimes are needed to scale our ability to detect, track, classify and characterize resident space objects in a crowded low Earth orbit. This research presents RSOnet, an image-processing framework for space domain awareness using star trackers. Star trackers are cost-effective, flight proven, and require basic image processing to be used as an attitude-determination sensor. RSOnet is designed to augment the capabilities of a star tracker by becoming an opportunistic space-surveillance sensor. Our research demonstrates that star trackers are a feasible source for RSO detections in LEO by demonstrating the performance of RSOnet on real detections from a star-tracker-like imager in space. RSOnet convolutional-neural-network model architecture, graph-based multi-object classifier and characterization results are described in this paper.

12.
New Phytol ; 229(6): 3195-3207, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33220075

RESUMEN

Character displacement can play a major role in species ecology and evolution; however, research testing whether character displacement can influence the evolution of root traits in plant systems remains scarce in the literature. Here we investigated the potential that character displacement may influence the evolution of root traits using two closely related morning glory species, Ipomoea purpurea and Ipomoea hederacea. We performed a field experiment where we grew the common morning glory, I. purpurea, in the presence and absence of competition from I. hederacea and examined the potential that the process of character displacement could influence the evolution of root traits. We found maternal line variation in root phenotypes and evidence that below-ground competition acts as an agent of selection on these traits. Our test of character displacement, however, showed evidence of character convergence on our measure of root architecture rather than displacement. These results suggest that plants may be constrained by their local environments to express a phenotype that enhances fitness. Therefore, the conditions of the competitive environment experienced by a plant may influence the potential for character convergence or displacement to influence the evolution of root traits.


Asunto(s)
Ipomoea , Selección Genética , Ecología , Fenotipo
13.
Mol Ecol ; 30(21): 5406-5421, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-32542840

RESUMEN

Herbicides act as human-mediated novel selective agents and community disruptors, yet their full effects on eco-evolutionary dynamics in natural communities have only begun to be appreciated. Here, we synthesize how herbicide exposures can result in dramatic phenotypic and compositional shifts within communities at the agro-ecological interface and how these in turn affect species interactions and drive plant (and plant-associates') evolution in ways that can feedback to continue to affect the ecology and ecosystem functions of these assemblages. We advocate a holistic approach to understanding these dynamics that includes plastic changes and plant community transformations and also extends beyond this single trophic level targeted by herbicides to the effects on nontarget plant-associated organisms and their potential to evolve, thereby embracing the complexity of these real-world systems. We make explicit recommendations for future research to achieve this goal and specifically address impacts of ecology on evolution, evolution on ecology and their feedbacks so that we can gain a more predictive view of the fates of herbicide-impacted communities.


Asunto(s)
Ecosistema , Herbicidas , Evolución Biológica , Retroalimentación , Herbicidas/toxicidad , Humanos , Plantas
14.
Mol Ecol ; 30(21): 5422-5437, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33604956

RESUMEN

Inbreeding depression is a central parameter underlying mating system variation in nature and one that can be altered by environmental stress. Although a variety of systems show that inbreeding depression tends to increase under stressful conditions, we have very little understanding across most organisms how the level of inbreeding depression may change as a result of adaptation to stressors. In this work we examined the potential that inbreeding depression varied among lineages of Ipomoea purpurea artificially evolved to exhibit divergent levels of herbicide resistance. We examined inbreeding depression in a variety of fitness-related traits in both the growth chamber and in the field, and paired this work with an examination of gene expression changes. We found that, while inbreeding depression was present across many of the traits, lineages artificially selected for increased herbicide resistance often showed no evidence of inbreeding depression in the presence of herbicide, and in fact, showed evidence of outbreeding depression in some traits compared to nonselected control lines and lineages selected for increased herbicide susceptibility. Further, at the transcriptome level, the resistant selection lines had differing patterns of gene expression according to breeding type (inbred vs. outcrossed) compared to the control and susceptible selection lines. Our data together indicate that inbreeding depression may be lessened in populations that are adapting to regimes of strong selection.


Asunto(s)
Herbicidas , Depresión Endogámica , Ipomoea , Resistencia a los Herbicidas/genética , Herbicidas/toxicidad , Endogamia , Depresión Endogámica/genética , Reproducción
15.
Med Care ; 59(10): 857-863, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34432769

RESUMEN

BACKGROUND: Evidence indicates hospitals with better registered nurse (RN) staffing have better patient outcomes. Whether involving more nurse practitioners (NPs) in inpatient care produces better outcomes is largely unknown. OBJECTIVE: The objective of this study was to determine whether the presence of more NPs produces better inpatient outcomes net of RN staffing. RESEARCH DESIGN: This was a 2015-2016 cross-sectional data on 579 hospitals linked from: (1) RN4CAST-US nurse surveys; (2) Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) patient surveys; (3) surgical patient discharge abstracts; (4) Medicare Spending per Beneficiary (MSPB) reports; (5) American Hospital Association (AHA) Annual Survey. Hospitals were grouped according to their NP/beds ratios [<1 NP/100 beds (N=132), 1-2.99 NPs/100 beds (N=279), and 3+ NPs/100 beds (N=168)]. SUBJECTS: RNs randomly sampled nurses from licensure lists yielded 22,273 RNs in study hospitals; discharge data for 1.4 million surgical patients; HCAHPS data for 86% of study hospitals. MEASURES: Mortality, readmissions, lengths of stay, MSPB, patient experience, and quality reported by patients and nurses. RESULTS: After adjustments, patients in hospitals with 3+ NPs/100 beds had lower odds than patients in hospitals with <1 NP/100 beds of 30-day mortality [odds ratio (OR)2=0.76; 95% confidence interval (CI)=0.67-0.82; P<0.001] and 7-day readmissions (OR2=0.90; 95% CI=0.86-0.96; P<0.001), shorter average length of stay (incident rate ratio2=0.92; 95% CI=0.88-0.96; P<0.001) and 5.4% lower average MSPB (95% CI=3.8%-7.1%). Patients and nurses in the hospitals with higher NP/bed ratios were significantly more likely to report better care quality and safety, and nurses reported lower burnout, higher job satisfaction, greater intentions of staying in their jobs. CONCLUSIONS: Having more NPs in hospitals has favorable effects on patients, staff nurse satisfaction, and efficiency. NPs add value to existing labor resources.


Asunto(s)
Pacientes Internos , Enfermeras Practicantes/provisión & distribución , Personal de Enfermería en Hospital , Estudios Transversales , Humanos , Medición de Resultados Informados por el Paciente , Calidad de la Atención de Salud , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
16.
Arch Womens Ment Health ; 24(5): 781-791, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33855652

RESUMEN

Limited research has examined factors that impact access to postpartum mental healthcare. We investigated the predisposing, enabling, and need factors associated with postpartum consultation for mental health concerns in US mothers with or without depressive symptoms and examined potential disparities in access. We utilized cross-sectional data from the Listening to Mothers II Survey, the second national US survey of women's childbearing experiences. The survey recruited 1573 women, aged 18-45 years, who spoke English and had given birth. Depressive symptoms were measured with the Postpartum Depression Screening Scale (PDSS-SF). The dependent variable was postpartum consultation for mental health concerns. Logistic regression analyses showed that mothers with scores of 14-21 and 22-35 on the PDSS-SF had higher odds of consulting a provider for mental health concerns (OR 3.97; OR 12.91). Latinas had lower odds of seeking mental health consultations than Whites (OR 0.39). Mothers who were employed prenatally full-time or part-time had lower odds of seeking consultations than non-employed mothers (OR 0.62; OR 0.52). Mothers with household incomes of $50,000-$74,999 had higher odds of seeking consultations than those with incomes less than $25,000 (OR 2.20). When regression analyses were restricted to mothers with PDSS-SF scores ≥ 14, findings were similar by race/ethnicity and prenatal employment. Significant depressive symptoms are common in women after giving birth and few sought any form of mental health consultation. Latinas and low-income women are less likely to seek postpartum mental health consultations. Mental health care interventions could be geared towards targeting these at-risk groups.


Asunto(s)
Depresión Posparto , Madres , Estudios Transversales , Depresión Posparto/diagnóstico , Depresión Posparto/epidemiología , Etnicidad , Femenino , Humanos , Salud Mental , Periodo Posparto , Pobreza , Embarazo , Derivación y Consulta
17.
Sensors (Basel) ; 21(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672501

RESUMEN

In recent years, we have seen significant improvements in the digital sun sensor (DSS) design enabled by advanced micro-systems fabrication and optical sensing technologies. In this paper, we propose a simple single-slit DSS concept with improved accuracy using sub-pixel interpolation. In considering the DSS design, we focused on several characteristics of the sun sensor, including field-of-view, sensor accuracy, complexity, and computational requirements. First, the optimal mask design was determined based on the simple geometry of the slit size, mask height and pixel width. Then, a two-step pixel read-out algorithm was implemented for sub-pixel level interpolation to determine the illumination ratio using 1-, 2-, 4- and 8-bit readouts. Lastly, the improved DSS was integrated with typical CubeSat, commercial-grade attitude sensors suite and a simple TRIAD method to determine the attitude of a CubeSat in LEO. Compared to standard 1-bit read-out mode (0.32 deg RMSE), 8-bit DSS achieves better than 0.01 deg RMSE. In a CubeSat scenario, improvements in attitude knowledge and control accuracy are marginal when using TRIAD, due to the significantly lower accuracy in other CubeSat-scale sensors (magnetometer, for example).

18.
Am Nat ; 195(4): 577-590, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32216668

RESUMEN

Although root traits play a critical role in mediating plant-plant interactions and resource acquisition from the soil environment, research examining whether and how belowground competition can influence the evolution of root traits remains largely unexplored. Here we examine the possibility that root traits may evolve as a target of selection from interspecific competition using Ipomoea purpurea and I. hederacea, two closely related morning glory species that commonly co-occur in the United States, as a model system. We show that belowground competitive interactions between the two species can alter the pattern of selection on root traits in each species. Specifically, competition with I. purpurea changes the pattern of selection on root angle in I. hederacea, and competitive interactions with I. hederacea change the pattern of selection on root size in I. purpurea. However, we did not uncover evidence that intraspecific competition altered the pattern of selection on any root traits within I. hederacea. Overall, our results suggest that belowground competition between closely related species can influence the phenotypic evolution of root traits in natural populations. Our findings provide a microevolutionary perspective of how competitive belowground interactions may impact plant fitness, potentially leading to patterns of plant community structure.


Asunto(s)
Ipomoea/anatomía & histología , Raíces de Plantas/anatomía & histología , Selección Genética , Evolución Biológica , Ipomoea/genética , Ipomoea/crecimiento & desarrollo , Fenotipo , Raíces de Plantas/crecimiento & desarrollo
19.
New Phytol ; 225(5): 2183-2195, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31652341

RESUMEN

Leaf shape, a spectacularly diverse plant trait, varies across taxonomic levels, geography and in response to environmental differences. However, comprehensive intraspecific analyses of leaf shape variation across variable environments is surprisingly absent. Here, we performed a multilevel analysis of leaf shape using diverse accessions of sweet potato (Ipomoea batatas), and uncovered the role of genetics, environment, and G×E on this important trait. We examined leaf shape using a variety of morphometric analyses, and complement this with a transcriptomic survey to identify gene expression changes associated with shape variation. Additionally, we examined the role of genetics and environment on leaf shape by performing field studies in two geographically separate common gardens. We showed that extensive leaf shape variation exists within I. batatas, and identified promising candidate genes associated with this variation. Interestingly, when considering traditional measures, we found that genetic factors are largely responsible for most of leaf shape variation, but that the environment is highly influential when using more quantitative measures via leaf outlines. This extensive and multilevel examination of leaf shape shows an important role of genetics underlying a potentially important agronomic trait, and highlights that the environment can be a strong influence when using more quantitative measures of leaf shape.


Asunto(s)
Ipomoea batatas , Hojas de la Planta/anatomía & histología , Ambiente , Interacción Gen-Ambiente , Ipomoea batatas/genética
20.
Arch Biochem Biophys ; 684: 108306, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32081684

RESUMEN

Maternal endotoxemia has been shown to increase renal collagen deposition in the offspring. Renal fibrosis is a hallmark of progressive chronic kidney disease. It was investigated whether maternal reactive oxygen species (ROS) leads to renal fibrosis or exacerbates unilateral ureteral obstruction (UUO)-induced renal fibrosis in the offspring of dams treated with lipopolysaccharide (LPS). Furthermore, it was studied the role of matrix metalloproteinases (MMPs) in these changes. Adults Wistar rats were obtained from dams submitted to LPS administration through the third part of gestation. To evaluate the role of maternal ROS, part of the dams received α-tocopherol simultaneously with LPS. Part of the offspring in each group was submitted to UUO at adulthood when sub-groups were treated with NADPH oxidase inhibitor, apocynin. Maternal LPS administration increased proteinuria, systolic arterial pressure and renal collagen deposition in adult offspring. LPS offspring rats also presented higher MMP-2 activity in parallel to a decreased renal cortical TIMP-2 content. These changes were correlated to increased amounts of TGF-ß1 and NOX2. Maternal α-tocopherol treatment prevented collagen deposition and reduced arterial pressure in adult offspring. α-Tocopherol also inhibited maternal endotoxemia-induced changes in TGF-ß1/NOX2/MMP-2 signaling. UUO led to increased collagen deposition in the contralateral kidneys of LPS offspring, which was correlated to increased NADPH oxidase activity and prevented by NADPH oxidase inhibition. In summary, maternal endotoxemia led to alterations in the TGF-ß1/NOX2/MMP-2 signaling pathway in renal tissue concomitant with collagen deposition, therefore contributing to hypertension in adult offspring.


Asunto(s)
Colágeno/metabolismo , Endotoxemia/complicaciones , Enfermedades Renales/etiología , Riñón/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Transducción de Señal/fisiología , Animales , Endotoxemia/inducido químicamente , Matriz Extracelular/metabolismo , Femenino , Fibrosis/etiología , Fibrosis/metabolismo , Lipopolisacáridos , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , NADPH Oxidasa 2/metabolismo , Embarazo , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta1/metabolismo , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/metabolismo , alfa-Tocoferol/farmacología
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