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1.
Nature ; 557(7705): 413-417, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29769666

RESUMEN

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.

2.
J Am Chem Soc ; 145(9): 5222-5230, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36779837

RESUMEN

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.


Asunto(s)
Productos Biológicos , Poliestirenos , Poliestirenos/metabolismo , Productos Biológicos/metabolismo , Plásticos/metabolismo , Polietileno/metabolismo , Aspergillus flavus/metabolismo
3.
Ecol Appl ; 31(7): e02411, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34255387

RESUMEN

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.


Asunto(s)
Incendios , Plantones , Ecosistema , Germinación , Semillas
4.
J Environ Manage ; 273: 111078, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32738742

RESUMEN

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.


Asunto(s)
Biodiversidad , Minería , Australia , Monitoreo del Ambiente , Australia Occidental
5.
New Phytol ; 221(4): 1764-1775, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30269352

RESUMEN

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.


Asunto(s)
Germinación/fisiología , Dispersión de Semillas/fisiología , Semillas/fisiología , Biodiversidad , Conservación de los Recursos Naturales , Bases de Datos Factuales , Ecosistema , Plantones/fisiología
6.
Proc Natl Acad Sci U S A ; 113(11): 2880-5, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26929368

RESUMEN

National-scale emissions of carbon tetrachloride (CCl4) are derived based on inverse modeling of atmospheric observations at multiple sites across the United States from the National Oceanic and Atmospheric Administration's flask air sampling network. We estimate an annual average US emission of 4.0 (2.0-6.5) Gg CCl4 y(-1) during 2008-2012, which is almost two orders of magnitude larger than reported to the US Environmental Protection Agency (EPA) Toxics Release Inventory (TRI) (mean of 0.06 Gg y(-1)) but only 8% (3-22%) of global CCl4 emissions during these years. Emissive regions identified by the observations and consistently shown in all inversion results include the Gulf Coast states, the San Francisco Bay Area in California, and the Denver area in Colorado. Both the observation-derived emissions and the US EPA TRI identified Texas and Louisiana as the largest contributors, accounting for one- to two-thirds of the US national total CCl4 emission during 2008-2012. These results are qualitatively consistent with multiple aircraft and ship surveys conducted in earlier years, which suggested significant enhancements in atmospheric mole fractions measured near Houston and surrounding areas. Furthermore, the emission distribution derived for CCl4 throughout the United States is more consistent with the distribution of industrial activities included in the TRI than with the distribution of other potential CCl4 sources such as uncapped landfills or activities related to population density (e.g., use of chlorine-containing bleach).

7.
J Pediatr Nurs ; 41: 16-21, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29132876

RESUMEN

PURPOSE: Distraction is a relatively simple, evidence-based intervention to minimize child distress during medical procedures. Timely on-site interventions that instruct parents on distraction coaching are needed. The purpose of this study was to test the feasibility and usability of the Distraction in Action Tool© (DAT©), which 1) predicts child risk for distress with a needle stick and 2) provides individualized instructions for parents on how to be a distraction coach for their child in clinical settings. DESIGN AND METHODS: A mixed-methods descriptive design was used to test feasibility and usability of DAT in the Emergency Department and a Phlebotomy Lab at a large Midwest Academic Medical Center. Twenty parents of children ages 4-10years requiring venipuncture and clinicians performing 13 of those procedures participated. Participants completed an evaluation and participated in a brief interview. RESULTS: The average age of the children was 6.8years, and 80% of parent participants were mothers. Most parents reported the DAT was not difficult to use (84.2%), understandable (100%), and they had a positive experience (89.5%). Clinicians thought DAT was helpful (100%) and did not cause a meaningful delay in workflow (92%). CONCLUSION: DAT can be used by parents and clinicians to assess their children's risk for procedure related distress and learn distraction techniques to help their children during needle stick procedures. PRACTICE IMPLICATIONS: DAT for parents is being disseminated via social media and an open-access website. Further research is needed to disseminate and implement DAT in community healthcare settings.

8.
Pol J Pathol ; 69(3): 314-318, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30509059

RESUMEN

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.


Asunto(s)
Angiomatosis/patología , Enfermedades Óseas/patología , Vasos Linfáticos/patología , Biopsia , Médula Ósea/patología , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad
9.
Proc Natl Acad Sci U S A ; 111(49): 17379-84, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25422438

RESUMEN

HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. In this work, we study in situ observations of HCFC-22 and HFC-134a taken from research aircraft over the Pacific Ocean in a 3-y span [HIaper-Pole-to-Pole Observations (HIPPO) 2009-2011] and combine these data with long-term ground observations from global surface sites [National Oceanic and Atmospheric Administration (NOAA) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks]. We find the global annual emissions of HCFC-22 and HFC-134a have increased substantially over the past two decades. Emissions of HFC-134a are consistently higher compared with the United Nations Framework Convention on Climate Change (UNFCCC) inventory since 2000, by 60% more in recent years (2009-2012). Apart from these decadal emission constraints, we also quantify recent seasonal emission patterns showing that summertime emissions of HCFC-22 and HFC-134a are two to three times higher than wintertime emissions. This unforeseen large seasonal variation indicates that unaccounted mechanisms controlling refrigerant gas emissions are missing in the existing inventory estimates. Possible mechanisms enhancing refrigerant losses in summer are (i) higher vapor pressure in the sealed compartment of the system at summer high temperatures and (ii) more frequent use and service of refrigerators and air conditioners in summer months. Our results suggest that engineering (e.g., better temperature/vibration-resistant system sealing and new system design of more compact/efficient components) and regulatory (e.g., reinforcing system service regulations) steps to improve containment of these gases from working devices could effectively reduce their release to the atmosphere.

10.
Proc Natl Acad Sci U S A ; 111(17): 6237-42, 2014 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-24733927

RESUMEN

The identification and quantification of methane emissions from natural gas production has become increasingly important owing to the increase in the natural gas component of the energy sector. An instrumented aircraft platform was used to identify large sources of methane and quantify emission rates in southwestern PA in June 2012. A large regional flux, 2.0-14 g CH4 s(-1) km(-2), was quantified for a ∼ 2,800-km(2) area, which did not differ statistically from a bottom-up inventory, 2.3-4.6 g CH4 s(-1) km(-2). Large emissions averaging 34 g CH4/s per well were observed from seven well pads determined to be in the drilling phase, 2 to 3 orders of magnitude greater than US Environmental Protection Agency estimates for this operational phase. The emissions from these well pads, representing ∼ 1% of the total number of wells, account for 4-30% of the observed regional flux. More work is needed to determine all of the sources of methane emissions from natural gas production, to ascertain why these emissions occur and to evaluate their climate and atmospheric chemistry impacts.

11.
Proc Natl Acad Sci U S A ; 110(50): 20018-22, 2013 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-24277804

RESUMEN

This study quantitatively estimates the spatial distribution of anthropogenic methane sources in the United States by combining comprehensive atmospheric methane observations, extensive spatial datasets, and a high-resolution atmospheric transport model. Results show that current inventories from the US Environmental Protection Agency (EPA) and the Emissions Database for Global Atmospheric Research underestimate methane emissions nationally by a factor of ∼1.5 and ∼1.7, respectively. Our study indicates that emissions due to ruminants and manure are up to twice the magnitude of existing inventories. In addition, the discrepancy in methane source estimates is particularly pronounced in the south-central United States, where we find total emissions are ∼2.7 times greater than in most inventories and account for 24 ± 3% of national emissions. The spatial patterns of our emission fluxes and observed methane-propane correlations indicate that fossil fuel extraction and refining are major contributors (45 ± 13%) in the south-central United States. This result suggests that regional methane emissions due to fossil fuel extraction and processing could be 4.9 ± 2.6 times larger than in EDGAR, the most comprehensive global methane inventory. These results cast doubt on the US EPA's recent decision to downscale its estimate of national natural gas emissions by 25-30%. Overall, we conclude that methane emissions associated with both the animal husbandry and fossil fuel industries have larger greenhouse gas impacts than indicated by existing inventories.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Atmósfera/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Metano/análisis , Agricultura/estadística & datos numéricos , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Industria Procesadora y de Extracción/estadística & datos numéricos , Modelos Químicos , Estados Unidos
12.
New Phytol ; 208(1): 13-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26171760

RESUMEN

Inventors in the field of mechanical and electronic engineering can access multitudes of components and, thanks to standardization, parts from different manufacturers can be used in combination with each other. The introduction of BioBrick standards for the assembly of characterized DNA sequences was a landmark in microbial engineering, shaping the field of synthetic biology. Here, we describe a standard for Type IIS restriction endonuclease-mediated assembly, defining a common syntax of 12 fusion sites to enable the facile assembly of eukaryotic transcriptional units. This standard has been developed and agreed by representatives and leaders of the international plant science and synthetic biology communities, including inventors, developers and adopters of Type IIS cloning methods. Our vision is of an extensive catalogue of standardized, characterized DNA parts that will accelerate plant bioengineering.


Asunto(s)
Clonación Molecular/métodos , ADN , Ingeniería Genética/métodos , Plantas Modificadas Genéticamente/genética , Plantas/genética , Biología Sintética/métodos , Botánica , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Eucariontes/genética , Ingeniería Genética/normas , Plásmidos , Estándares de Referencia , Transcripción Genética
13.
Anal Chem ; 86(5): 2580-9, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24555659

RESUMEN

Studies of climate change increasingly recognize the diverse influences of hydrocarbons in the atmosphere, including roles in particulates and ozone formation. Measurements of key nonmethane hydrocarbons (NMHCs) suggest atmospheric mole fractions ranging from low picomoles per mol (ppt) to nanomoles per mol (ppb), depending on location and compound. To accurately establish mole fraction trends and to relate measurement records from many laboratories and researchers, it is essential to have accurate, stable, calibration standards. In February of 2008, the National Institute of Standards and Technology (NIST) developed and reported on picomoles per mol standards containing 18 nonmethane hydrocarbon compounds covering the mole fraction range of 60 picomoles per mol to 230 picomoles per mol. The stability of these gas mixtures was only characterized over a short time period (2 to 3 months). NIST recently prepared a suite of primary standard gas mixtures by gravimetric dilution to ascertain the stability of the 2008 picomoles per mol NMHC standards suite. The data from this recent chromatographic intercomparison of the 2008 to the 2011 suites confirm a much longer stability of almost 5 years for 15 of the 18 hydrocarbons; the double-bonded alkenes of propene, isobutene, and 1-pentene showed instability, in line with previous publications. The agreement between the gravimetric values from preparation and the analytical mole fractions determined from regression illustrate the internal consistency of the suite within ±2 pmol/mol. However, results for several of the compounds reflect stability problems for the three double-bonded hydrocarbons. An international intercomparison on one of the 2008 standards has also been completed. Participants included National Metrology Institutes, United States government laboratories, and academic laboratories. In general, results for this intercomparison agree to within about ±5% with the gravimetric mole fractions of the hydrocarbons.

14.
Physiol Plant ; 152(2): 301-15, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24547765

RESUMEN

Southwest Australian Banksia woodlands are highly diverse plant communities that are threatened by drought- or temperature-induced mortality due to the region's changing climate. We examined water relations in dominant Banksia menziesii R. Br. trees using magnetic leaf patch clamp pressure (ZIM-) probes that allow continuous, real-time monitoring of leaf water status. Multiple ZIM-probes across the crown were complemented by traditional ecophysiological measurements. During summer, early stomatal downregulation of transpiration prevented midday balancing pressures from exceeding 2.5 MPa. Diurnal patterns of ZIM-probe and pressure chamber readings agreed reasonably well, however, ZIM-probes recorded short-term dynamics, which are impossible to capture using a pressure chamber. Simultaneous recordings of three ZIM-probes evenly spaced along leaf laminas revealed intrafoliar turgor gradients, which, however, did not develop in a strictly basi- or acropetal fashion and varied with cardinal direction. Drought stress manifested as increasing daily signal amplitude (low leaf water status) and occasionally as rising baseline at night (delayed rehydration). These symptoms occurred more often locally than across the entire crown. Microclimate effects on leaf water status were strongest in crown regions experiencing peak morning radiation (East and North). Extreme spring temperatures preceded the sudden death of B. menziesii trees, suggesting a temperature- or humidity-related tipping point causing rapid hydraulic failure as evidenced by collapsing ZIM-probe readings from an affected tree. In a warmer and drier future, increased frequency of B. menziesii mortality will result in significantly altered community structure and ecosystem function.


Asunto(s)
Sequías , Proteaceae/fisiología , Análisis Espacio-Temporal , Árboles/fisiología , Agua/fisiología , Australia , Ritmo Circadiano/fisiología , Exudados de Plantas/fisiología , Hojas de la Planta/fisiología , Estomas de Plantas/fisiología , Transpiración de Plantas/fisiología , Reología , Temperatura , Presión de Vapor
15.
Eur J Appl Physiol ; 114(12): 2529-37, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25115507

RESUMEN

PURPOSE: In athletes, caffeine use is common although its effects on sleep have not been widely studied. This randomised, double-blind, placebo-controlled crossover trial investigated the effects of late-afternoon caffeine and carbohydrate-electrolyte (CEB) co-ingestion on cycling performance and nocturnal sleep. METHODS: Six male cyclists/triathletes (age 27.5 ± 6.9 years) completed an afternoon training session (TS; cycling 80 min; 65% VO2max) followed by a 5 kJ kg(-1) cycling time trial (TT). Caffeine (split dose 2 × 3 mg kg(-1)) or placebo was administered 1 h prior and 40 min into the TS. A 7.4% CEB (3 ml kg(-1) every 15 min) was administered during the TS, followed 30 min after by a standardised evening meal. Participants retired at their usual bedtime and indices of sleep duration and quality were monitored via polysomnography. DATA: mean ± SD. RESULTS: All participants performed better in the caffeine TT (caffeine 19.7 ± 3.3; placebo 20.5 ± 3.5 min; p = 0.006), while ratings of perceived exertion (caffeine 12.0 ± 0.6; placebo 12.9 ± 0.7; p = 0.004) and heart rate (caffeine 175 ± 6; placebo 167 ± 11 bpm; p = 0.085) were lower in the caffeine TS. Caffeine intake induced significant disruptions to a number of sleep indices including increased sleep onset latency (caffeine 51.1 ± 34.7; placebo 10.2 ± 4.2 min; p = 0.028) and decreased sleep efficiency (caffeine 76.1 ± 19.6; placebo 91.5 ± 4.2%; p = 0.028), rapid eye movement sleep (caffeine 62.1 ± 19.6; placebo 85.8 ± 24.7 min; p = 0.028) and total sleep time (caffeine 391 ± 97; placebo 464 ± 49 min; p = 0.028). CONCLUSIONS: This study supports a performance-enhancing effect of caffeine, although athletes (especially those using caffeine for late-afternoon/evening training and competition) should consider its deleterious effects on sleep.


Asunto(s)
Ciclismo , Cafeína/administración & dosificación , Carbohidratos de la Dieta/administración & dosificación , Sustancias para Mejorar el Rendimiento/administración & dosificación , Resistencia Física/efectos de los fármacos , Sueño/efectos de los fármacos , Adulto , Atletas , Rendimiento Atlético , Método Doble Ciego , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Consumo de Oxígeno/efectos de los fármacos , Polisomnografía , Adulto Joven
16.
bioRxiv ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38585735

RESUMEN

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.

17.
Front Psychol ; 14: 1176786, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731866

RESUMEN

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.

18.
J Am Coll Surg ; 237(3): 525-532, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37171090

RESUMEN

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.


Asunto(s)
Hernia Inguinal , Humanos , Hernia Inguinal/cirugía , Calidad de Vida , Medición de Resultados Informados por el Paciente , Encuestas y Cuestionarios , Dolor
19.
Top Curr Chem (Cham) ; 380(6): 52, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36207646

RESUMEN

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.


Asunto(s)
Catálisis , Microscopía Electrónica de Transmisión
20.
Front Plant Sci ; 12: 795003, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35069650

RESUMEN

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.

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