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1.
bioRxiv ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38585735

RESUMO

The pregnancy hormone, human chorionic gonadotropin (hCG) is an immunoregulatory and neurotrophic glycoprotein of potential clinical utility in the neonate at risk for cerebral injury. Despite its well-known role in its ability to modulate the innate immune response during pregnancy, hCG has not been demonstrated to affect the pro-degenerative actions of inflammation in neonatal hypoxia-ischemia (HI). Here we utilize a neonatal mouse model of mild HI combined with intraperitoneal administration of lipopolysaccharide (LPS) to evaluate the neuroprotective actions of hCG in the setting of endotoxin-mediated systemic inflammation. Intraperitoneal treatment of hCG shortly prior to LPS injection significantly decreased tissue loss and cystic degeneration in the hippocampal and cerebral cortex in the term-equivalent neonatal mouse exposed to mild HI. Noting that parvalbumin immunoreactive interneurons have been broadly implicated in neurodevelopmental disorders, it is notable that hCG significantly improved the injury-mediated reduction of these neurons in the cerebral cortex, striatum and hippocampus. The above findings were associated with a decrease in the amount of Iba1 immunoreactive microglia in most of these brain regions. These observations implicate hCG as an agent capable of improving the neurological morbidity associated with peripheral inflammation in the neonate affected by HI. Future preclinical studies should aim at demonstrating added neuroprotective benefit by hCG in the context of therapeutic hypothermia and further exploring the mechanisms responsible for this effect. This research is likely to advance the therapeutic role of gonadotropins as a treatment for neonates with neonatal brain injury.

2.
Front Psychol ; 14: 1176786, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731866

RESUMO

Background: Compassion satisfaction (CS) is a phenomenon that has been studied among the helping professions, such as nursing and social work and has been linked to stress, burnout, compassion fatigue, and vicarious trauma. Social work educators may also experience these same issues, yet more research is needed on how they might counter the negative impacts associated with this type of work by utilizing their experiences of CS. Objectives: A phenomenological study was carried out to explore and describe how social work educators in higher education experiences CS. Methods: Eleven in-depth interviews with social work educators were conducted, and constructivist grounded theory techniques were utilized to analyze the data. Results: Social work educators experienced CS within the education and personal realms, which encompassed four different elements: achievement, support, balance, and empathy. Discussion: The four elements of CS were utilized by social work educators in this study as coping strategies to enhance their experience of CS, thus encountering threats to CS, such as institutional barriers, interaction with administrators and colleagues, and work overload. Conclusion: Interventions fostering compassion satisfaction and reducing compassion fatigue, burnout, and stress should be considered, including interventions that increase the sense of accomplishment, promote holistic self-care, encourage administrative and collegial support, and improve work-life balance.

3.
J Am Coll Surg ; 237(3): 525-532, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37171090

RESUMO

BACKGROUND: Patient-reported outcomes in clinical research allow for a more comprehensive and meaningful assessment of interventions but are subjective and difficult to interpret. European Registry for Abdominal Wall Hernias-Quality of Life (EuraHS-QoL) is a tool designed to assess perioperative quality of life for patients undergoing inguinal hernia repair, one of the most performed operations worldwide. Defining the minimum clinically important difference (MCID) for EuraHS-QoL tool can help standardize its interpretation for research purposes and facilitate improved shared decision making in clinical settings. STUDY DESIGN: A combination of 3 approaches for estimating MCIDs was used in this study. First, 2 distribution-based approaches were used that based estimates on statistical parameters of the data. The SEM provided a minimum value for the MCID, and one-half of the SD provided a point estimate of the MCID. Second, anchor-based approaches integrated patient perceptions of their overall well-being before and after surgery to provide benchmarks for the MCID. Last, iterative surveys of expert hernia surgeons were used to yield the final MCIDs for each domain and the composite EuraHS-QoL score. RESULTS: The overall range of EuraHS-QoL is 0 to 90, with subdomain ranges of 0 to 30 for the pain domain, 0 to 40 for the restriction of activities domain, and 0 to 20 for the cosmesis domain, with higher scores representing worse outcomes. The overall MCID for EuraHS-QoL is 10. Domain-specific MCIDs are 3 for the pain domain, 5 for the restriction of activities domain, and 2 for the cosmesis domain. CONCLUSIONS: In this study, we define overall and domain-specific MCIDs for the EuraHS-QoL instrument using statistical methods, patient-based methods, and clinical expertise, providing estimates that are both statistically and clinically significant.


Assuntos
Hérnia Inguinal , Humanos , Hérnia Inguinal/cirurgia , Qualidade de Vida , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários , Dor
4.
J Am Chem Soc ; 145(9): 5222-5230, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36779837

RESUMO

Polystyrene (PS) is one of the most used yet infrequently recycled plastics. Although manufactured on the scale of 300 million tons per year globally, current approaches toward PS degradation are energy- and carbon-inefficient, slow, and/or limited in the value that they reclaim. We recently reported a scalable process to degrade post-consumer polyethylene-containing waste streams into carboxylic diacids. Engineered fungal strains then upgrade these diacids biosynthetically to synthesize pharmacologically active secondary metabolites. Herein, we apply a similar reaction to rapidly convert PS to benzoic acid in high yield. Engineered strains of the filamentous fungus Aspergillus nidulans then biosynthetically upgrade PS-derived crude benzoic acid to the structurally diverse secondary metabolites ergothioneine, pleuromutilin, and mutilin. Further, we expand the catalog of plastic-derived products to include spores of the industrially relevant biocontrol agent Aspergillus flavus Af36 from crude PS-derived benzoic acid.


Assuntos
Produtos Biológicos , Poliestirenos , Poliestirenos/metabolismo , Produtos Biológicos/metabolismo , Plásticos/metabolismo , Polietileno/metabolismo , Aspergillus flavus/metabolismo
5.
Top Curr Chem (Cham) ; 380(6): 52, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36207646

RESUMO

In situ characterization of materials in their operational state is a highly active field of research. Investigating the structure and response of materials under stimuli that simulate real working environments for technological applications can provide new insight and unique input to the synthesis and design of novel materials. Over recent decades, experimental setups that allow different stimuli to be applied to a sample inside an electron microscope have been devised, built, and commercialized. In this review, we focus on the in situ investigation of optically active materials using transmission electron microscopy. We illustrate two different approaches for exposing samples to light inside the microscope column, explaining the importance of different aspects of their mechanical construction and choice of light source and materials. We focus on the technical challenges of the setups and provide details of the construction, providing the reader with input on deciding which setup will be more useful for a specific experiment. The use of these setups is illustrated using examples from the literature of relevance to photocatalysis and nanoparticle synthesis.


Assuntos
Catálise , Microscopia Eletrônica de Transmissão
6.
Ecol Appl ; 31(7): e02411, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34255387

RESUMO

Unseasonal fire occurrence is increasing globally, driven by climate change and other human activity. Changed timing of fire can inhibit postfire seedling recruitment through interactions with plant phenology (the timing of key processes, e.g., flower initiation, seed production, dispersal, germination), and therefore threaten the persistence of many plant species. Although empirical evidence from winter-rainfall ecosystems shows that optimal seedling recruitment is expected following summer and autumn (dry season) fires, we sought experimental evidence isolating the mechanisms of poor recruitment following unseasonal (wet season) fire. We implemented a seed-sowing experiment using nine species native to fire-prone, Mediterranean-climate woodlands in southwestern Australia to emulate the timing of postfire recruitment and test key mechanisms of fire seasonality effects. For seeds sown during months when fire is unseasonal (i.e., August-September: end of the wet winter season), seedling recruitment was reduced by up to 99% relative to seeds sown during seasonal fire months (i.e., May-June: end of the dry summer season) because of varying seed persistence, seedling emergence, and seedling survival. We found that up to 70 times more seedlings emerged when seeds were sown during seasonal fire months compared to when seeds were sown during unseasonal fire months. The few seedlings that emerged from unseasonal sowings all died with the onset of the dry season. Of the seeds that failed to germinate from unseasonal sowings, only 2% survived exposure on the soil surface over the ensuing hot and dry summer. Our experimental results demonstrate the potential for unseasonal fire to inhibit seedling recruitment via impacts on pregermination seed persistence and seedling establishment. As ongoing climate change lengthens fire seasons (i.e., unseasonal wildfires become more common) and managed fires are implemented further outside historically typical fire seasons, postfire seedling recruitment may become more vulnerable to failure, causing shifts in plant community composition towards those with fewer species solely dependent on seeds for regeneration.


Assuntos
Incêndios , Plântula , Ecossistema , Germinação , Sementes
7.
Front Plant Sci ; 12: 795003, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069650

RESUMO

Changes in fire regimes due to climate change and fire management practices are affecting the timing, length, and distribution of vegetation fires throughout the year. Plant species responses and tolerances to fire differ from season to season and are influenced by species-specific phenological processes. The ability of seeds to tolerate extreme temperatures associated with fire is one of these processes, with survival linked to seed moisture content at the time of exposure. As fire is more often occurring outside historic dry fire seasons, the probability of fire occurring when seeds are hydrated may also be increasing. In this study, we set out to understand the seasonal dynamics of seed hydration for seeds of Banksia woodland species, and how certain seed traits interact with environmental conditions to influence survival of high temperatures associated with fire. We measured the moisture content of seeds buried to 2 cm in the soil seed bank for four common native species and one invasive species on a weekly basis throughout 2017, along with soil moisture content and environmental correlates. We determined water sorption isotherms at 20°C for seeds of each species and used these functions to model weekly variation in seed water activity and predict when seeds are most sensitive to soil heating. Using Generalised additive models (GAMs), we were able to describe approximately 67% of the weekly variance in seed water activity and explored differences in seed hydration dynamics between species. Seed water activity was sufficiently high (i.e., ≥ 0.85 a w) so as to have created an increased risk of mortality if a fire had occurred during an almost continuous period between May and November in the study period (i.e., 2017). There were brief windows when seeds may have been in a dry state during early winter and late spring, and also when they may have been in a wet state during summer and late autumn. These data, and the associated analyses, provide an opportunity to develop approaches to minimize seed mortality during fire and maximize the seed bank response.

8.
IEEE Trans Pattern Anal Mach Intell ; 43(12): 4272-4290, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32750769

RESUMO

What is the current state-of-the-art for image restoration and enhancement applied to degraded images acquired under less than ideal circumstances? Can the application of such algorithms as a pre-processing step improve image interpretability for manual analysis or automatic visual recognition to classify scene content? While there have been important advances in the area of computational photography to restore or enhance the visual quality of an image, the capabilities of such techniques have not always translated in a useful way to visual recognition tasks. Consequently, there is a pressing need for the development of algorithms that are designed for the joint problem of improving visual appearance and recognition, which will be an enabling factor for the deployment of visual recognition tools in many real-world scenarios. To address this, we introduce the UG 2 dataset as a large-scale benchmark composed of video imagery captured under challenging conditions, and two enhancement tasks designed to test algorithmic impact on visual quality and automatic object recognition. Furthermore, we propose a set of metrics to evaluate the joint improvement of such tasks as well as individual algorithmic advances, including a novel psychophysics-based evaluation regime for human assessment and a realistic set of quantitative measures for object recognition performance. We introduce six new algorithms for image restoration or enhancement, which were created as part of the IARPA sponsored UG 2 Challenge workshop held at CVPR 2018. Under the proposed evaluation regime, we present an in-depth analysis of these algorithms and a host of deep learning-based and classic baseline approaches. From the observed results, it is evident that we are in the early days of building a bridge between computational photography and visual recognition, leaving many opportunities for innovation in this area.

11.
J Environ Manage ; 273: 111078, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738742

RESUMO

The mining industry is a major contributor to Australia's economy. However, such returns may come at high environmental and social costs, including loss of biodiversity or heritage values. Thus, companies worldwide are required to rehabilitate mine sites to a state that is safe, non-polluting and capable of supporting an agreed post-mining land use. While national and international guidelines on mine rehabilitation and closure exist, there is a lack of guidance on how to define achievable and measurable criteria that reflect rehabilitation success. This often leads to discrepancies between proponents and regulators, which hinder progression towards mine closure and relinquishment. The purpose of this study was to develop a systematic framework for the definition of completion criteria for mine closure and rehabilitation. The study was informed by a global review of the literature and collaborative research with mining stakeholders from Western Australia. The proposed framework consists of six fundamental steps: 1) selection of post mining land use; 2) definition of aspects and closure objectives; 3) selection of reference(s); 4) selection of attributes; 5) definition of completion criteria; and 6) evaluation of performance. This framework is the first to provide a step-by-step guide for defining site-specific completion criteria and applying a risk-based monitoring approach throughout the life of mine. The framework is applicable across jurisdictions and industries, in Australia and internationally, that require similar rehabilitation of disturbed lands.


Assuntos
Biodiversidade , Mineração , Austrália , Monitoramento Ambiental , Austrália Ocidental
12.
Ecol Evol ; 10(2): 763-777, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32015842

RESUMO

Short-range endemic plants often have edaphic specializations that, with their restricted distributions, expose them to increased risk of anthropogenic extinction.Here, we present a modeling approach to understand habitat suitability for Ricinocarpos brevis R.J.F.Hend. & Mollemans (Euphorbiaceae), a threatened shrub confined to three isolated populations in the semi-arid south-west of Western Australia. The model is a maximum entropy species distribution projection constructed on the basis of physical soil characteristics and geomorphology data at approximately 25 m2 (1 arc-second) resolution.The model predicts the species to occur on shallow, low bulk density soils that are located high in the landscape. The model shows high affinity (72.1% average likelihood of occurrence) for the known populations of R. brevis, as well as identifying likely locations that are not currently known to support the species. There was a strong relationship between the likelihood of R. brevis occurrence and soil moisture content that the model estimated at a depth of 20 cm.We advocate that our approach should be standardized using publicly available data to generate testable hypotheses for the distribution and conservation management of short-range endemic plant species for all of continental Australia.

14.
Trends Ecol Evol ; 34(12): 1104-1117, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31399287

RESUMO

Altered fire regimes resulting from climate change and human activity threaten many terrestrial ecosystems. However, we lack a holistic and detailed understanding of the effects of altering one key fire regime component - season of fire. Altered fire seasonality can strongly affect post-fire recovery of plant populations through interactions with plant phenology. We identify seven key mechanisms of fire seasonality effects under a conceptual demographic framework and review evidence for these. We reveal negative impacts of altered fire seasonality and identify research gaps for mechanisms and climate types for future analyses of fire seasonality effects within the identified demographic framework. This framework and these mechanisms can inform critical decisions for conservation, land management, and fire management policy development globally.


Assuntos
Ecossistema , Incêndios , Mudança Climática , Atividades Humanas , Humanos , Plantas
15.
Front Plant Sci ; 10: 283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930918

RESUMO

Wildfires are a natural component in many terrestrial ecosystems and often play a crucial role in maintaining biodiversity, particularly in the fire-prone regions of Australia. A prime example of plants that are able to persist in these regions is the genus Banksia. Most Banksia species that occur in fire-prone regions produce woody seed pods (follicles), which open during or soon after fire to release seeds into the post-fire environment. For population persistence, many Banksia species depend on recruitment from these canopy-stored seeds. Therefore, it is critical that their seeds are protected from heat and rapid oxidation during fire. Here, we show how different species of Banksia protect their seeds inside follicles while simultaneously opening up when experiencing fire. The ability of the follicles to protect seeds from heat is demonstrated by intense 180 s experimental burns, in which the maximum temperatures near the seeds ranged from ∼75°C for B. serrata to ∼90°C for B. prionotes and ∼95°C for B. candolleana, contrasting with the mean surface temperature of ∼450°C. Many seeds of native Australian plants, including those of Banksia, are able to survive these temperatures. Structural analysis of individual follicles from these three Banksia species demonstrates that all of them rely on a multicomponent system, consisting of two valves, a porous separator and a thin layer of air surrounding the seeds. The particular geometric arrangement of these components determines the rate of heat transfer more than the tissue properties alone, revealing that a strong embedment into the central rachis can compensate for thin follicle valves. Furthermore, we highlight the role of the separator as an important thermal insulator. Our study suggests that the genus Banksia employs a variety of combinations in terms of follicle size, valve thickness, composition and geometric arrangement to effectively protect canopy-stored seeds during fire.

16.
New Phytol ; 221(4): 1764-1775, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30269352

RESUMO

Trait-based approaches have improved our understanding of plant evolution, community assembly and ecosystem functioning. A major challenge for the upcoming decades is to understand the functions and evolution of early life-history traits, across levels of organization and ecological strategies. Although a variety of seed traits are critical for dispersal, persistence, germination timing and seedling establishment, only seed mass has been considered systematically. Here we suggest broadening the range of morphological, physiological and biochemical seed traits to add new understanding on plant niches, population dynamics and community assembly. The diversity of seed traits and functions provides an important challenge that will require international collaboration in three areas of research. First, we present a conceptual framework for a seed ecological spectrum that builds upon current understanding of plant niches. We then lay the foundation for a seed-trait functional network, the establishment of which will underpin and facilitate trait-based inferences. Finally, we anticipate novel insights and challenges associated with incorporating diverse seed traits into predictive evolutionary ecology, community ecology and applied ecology. If the community invests in standardized seed-trait collection and the implementation of rigorous databases, major strides can be made at this exciting frontier of functional ecology.


Assuntos
Germinação/fisiologia , Dispersão de Sementes/fisiologia , Sementes/fisiologia , Biodiversidade , Conservação dos Recursos Naturais , Bases de Dados Factuais , Ecossistema , Plântula/fisiologia
17.
Pol J Pathol ; 69(3): 314-318, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30509059

RESUMO

A 56-year-old female presented with popliteal venous thrombosis, splenomegaly, and sclerotic bone lesions. Bone marrow biopsy showed fibrosis, proliferation of abnormal blood vessels and lymphatics, bone remodelling, and no significant changes in haematopoietic elements. Following a relatively indolent initial clinical course, one year later she rapidly deteriorated and died of respiratory failure associated with widespread disease. Ingrowth of podoplanin+ lymphatics mixed with CD34+/podoplanin- blood vessels into the bone marrow is a new finding and may be a unique feature of this disease.


Assuntos
Angiomatose/patologia , Doenças Ósseas/patologia , Vasos Linfáticos/patologia , Biópsia , Medula Óssea/patologia , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade
18.
Sci Rep ; 8(1): 13094, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30166559

RESUMO

Heat waves have profoundly impacted biota globally over the past decade, especially where their ecological impacts are rapid, diverse, and broad-scale. Although usually considered in isolation for either terrestrial or marine ecosystems, heat waves can straddle ecosystems of both types at subcontinental scales, potentially impacting larger areas and taxonomic breadth than previously envisioned. Using climatic and multi-species demographic data collected in Western Australia, we show that a massive heat wave event straddling terrestrial and maritime ecosystems triggered abrupt, synchronous, and multi-trophic ecological disruptions, including mortality, demographic shifts and altered species distributions. Tree die-off and coral bleaching occurred concurrently in response to the heat wave, and were accompanied by terrestrial plant mortality, seagrass and kelp loss, population crash of an endangered terrestrial bird species, plummeting breeding success in marine penguins, and outbreaks of terrestrial wood-boring insects. These multiple taxa and trophic-level impacts spanned >300,000 km2-comparable to the size of California-encompassing one terrestrial Global Biodiversity Hotspot and two marine World Heritage Areas. The subcontinental multi-taxa context documented here reveals that terrestrial and marine biotic responses to heat waves do not occur in isolation, implying that the extent of ecological vulnerability to projected increases in heat waves is underestimated.


Assuntos
Organismos Aquáticos/fisiologia , Temperatura Alta , Filogenia , Mudança Climática
19.
J R Soc Interface ; 15(143)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29925581

RESUMO

Many plants in fire-prone regions retain their seeds in woody fruits in the plant canopy until the passage of a fire causes the fruit to open and release the seeds. To enable this function, suitable tissues are required that effectively store and protect seeds until they are released. Here, we show that three different species of the Australian genus Banksia incorporate waxes at the interface of the two valves of the follicle enclosing the seeds, which melt between 45°C and 55°C. Since the melting temperature of the waxes is lower than the opening temperatures of the follicles in all investigated species (B. candolleana, B. serrata, B. attenuata), we propose that melting of these waxes allows the sealing of micro-fissures at the interface of the two valves while they are still closed. Such a self-sealing mechanism likely contributes to the structural integrity of the seed pods, and benefits seed viability and persistence during storage on the plants. Furthermore, we show in a simplified, bioinspired model system that temperature treatments seal artificially applied surface cuts and restore the barrier properties.


Assuntos
Temperatura Alta , Modelos Biológicos , Proteaceae/metabolismo , Sementes/metabolismo , Ceras/metabolismo
20.
Nature ; 557(7705): 413-417, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29769666

RESUMO

The Montreal Protocol was designed to protect the stratospheric ozone layer by enabling reductions in the abundance of ozone-depleting substances such as chlorofluorocarbons (CFCs) in the atmosphere1-3. The reduction in the atmospheric concentration of trichlorofluoromethane (CFC-11) has made the second-largest contribution to the decline in the total atmospheric concentration of ozone-depleting chlorine since the 1990s 1 . However, CFC-11 still contributes one-quarter of all chlorine reaching the stratosphere, and a timely recovery of the stratospheric ozone layer depends on a sustained decline in CFC-11 concentrations 1 . Here we show that the rate of decline of atmospheric CFC-11 concentrations observed at remote measurement sites was constant from 2002 to 2012, and then slowed by about 50 per cent after 2012. The observed slowdown in the decline of CFC-11 concentration was concurrent with a 50 per cent increase in the mean concentration difference observed between the Northern and Southern Hemispheres, and also with the emergence of strong correlations at the Mauna Loa Observatory between concentrations of CFC-11 and other chemicals associated with anthropogenic emissions. A simple model analysis of our findings suggests an increase in CFC-11 emissions of 13 ± 5 gigagrams per year (25 ± 13 per cent) since 2012, despite reported production being close to zero 4 since 2006. Our three-dimensional model simulations confirm the increase in CFC-11 emissions, but indicate that this increase may have been as much as 50 per cent smaller as a result of changes in stratospheric processes or dynamics. The increase in emission of CFC-11 appears unrelated to past production; this suggests unreported new production, which is inconsistent with the Montreal Protocol agreement to phase out global CFC production by 2010.

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