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1.
Nature ; 629(8011): 295-306, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720037

RESUMEN

Fossil fuels-coal, oil and gas-supply most of the world's energy and also form the basis of many products essential for everyday life. Their use is the largest contributor to the carbon dioxide emissions that drive global climate change, prompting joint efforts to find renewable alternatives that might enable a carbon-neutral society by as early as 2050. There are clear paths for renewable electricity to replace fossil-fuel-based energy, but the transport fuels and chemicals produced in oil refineries will still be needed. We can attempt to close the carbon cycle associated with their use by electrifying refinery processes and by changing the raw materials that go into a refinery from fossils fuels to carbon dioxide for making hydrocarbon fuels and to agricultural and municipal waste for making chemicals and polymers. We argue that, with sufficient long-term commitment and support, the science and technology for such a completely fossil-free refinery, delivering the products required after 2050 (less fuels, more chemicals), could be developed. This future refinery will require substantially larger areas and greater mineral resources than is the case at present and critically depends on the capacity to generate large amounts of renewable energy for hydrogen production and carbon dioxide capture.


Asunto(s)
Dióxido de Carbono , Combustibles Fósiles , Industria del Petróleo y Gas , Energía Renovable , Ciclo del Carbono , Dióxido de Carbono/efectos adversos , Dióxido de Carbono/aislamiento & purificación , Carbón Mineral/efectos adversos , Carbón Mineral/provisión & distribución , Combustibles Fósiles/efectos adversos , Combustibles Fósiles/provisión & distribución , Hidrógeno/química , Gas Natural/efectos adversos , Gas Natural/provisión & distribución , Petróleo/efectos adversos , Petróleo/provisión & distribución , Energía Renovable/estadística & datos numéricos , Industria del Petróleo y Gas/métodos , Industria del Petróleo y Gas/tendencias
2.
Elife ; 132024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727716

RESUMEN

PHOX2B is a transcription factor essential for the development of different classes of neurons in the central and peripheral nervous system. Heterozygous mutations in the PHOX2B coding region are responsible for the occurrence of Congenital Central Hypoventilation Syndrome (CCHS), a rare neurological disorder characterised by inadequate chemosensitivity and life-threatening sleep-related hypoventilation. Animal studies suggest that chemoreflex defects are caused in part by the improper development or function of PHOX2B expressing neurons in the retrotrapezoid nucleus (RTN), a central hub for CO2 chemosensitivity. Although the function of PHOX2B in rodents during development is well established, its role in the adult respiratory network remains unknown. In this study, we investigated whether reduction in PHOX2B expression in chemosensitive neuromedin-B (NMB) expressing neurons in the RTN altered respiratory function. Four weeks following local RTN injection of a lentiviral vector expressing the short hairpin RNA (shRNA) targeting Phox2b mRNA, a reduction of PHOX2B expression was observed in Nmb neurons compared to both naive rats and rats injected with the non-target shRNA. PHOX2B knockdown did not affect breathing in room air or under hypoxia, but ventilation was significantly impaired during hypercapnia. PHOX2B knockdown did not alter Nmb expression but it was associated with reduced expression of both Task2 and Gpr4, two CO2/pH sensors in the RTN. We conclude that PHOX2B in the adult brain has an important role in CO2 chemoreception and reduced PHOX2B expression in CCHS beyond the developmental period may contribute to the impaired central chemoreflex function.


Asunto(s)
Dióxido de Carbono , Proteínas de Homeodominio , Factores de Transcripción , Animales , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Dióxido de Carbono/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ratas , Técnicas de Silenciamiento del Gen , Masculino , Hipoventilación/genética , Hipoventilación/congénito , Hipoventilación/metabolismo , Células Quimiorreceptoras/metabolismo , Ratas Sprague-Dawley , Apnea Central del Sueño/genética , Apnea Central del Sueño/metabolismo , Neuronas/metabolismo , Neuronas/fisiología
3.
Sci Adv ; 10(19): eadk7283, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38728392

RESUMEN

Cyanobacterial CO2 concentrating mechanisms (CCMs) sequester a globally consequential proportion of carbon into the biosphere. Proteinaceous microcompartments, called carboxysomes, play a critical role in CCM function, housing two enzymes to enhance CO2 fixation: carbonic anhydrase (CA) and Rubisco. Despite its importance, our current understanding of the carboxysomal CAs found in α-cyanobacteria, CsoSCA, remains limited, particularly regarding the regulation of its activity. Here, we present a structural and biochemical study of CsoSCA from the cyanobacterium Cyanobium sp. PCC7001. Our results show that the Cyanobium CsoSCA is allosterically activated by the Rubisco substrate ribulose-1,5-bisphosphate and forms a hexameric trimer of dimers. Comprehensive phylogenetic and mutational analyses are consistent with this regulation appearing exclusively in cyanobacterial α-carboxysome CAs. These findings clarify the biologically relevant oligomeric state of α-carboxysomal CAs and advance our understanding of the regulation of photosynthesis in this globally dominant lineage.


Asunto(s)
Anhidrasas Carbónicas , Cianobacterias , Ribulosa-Bifosfato Carboxilasa , Ribulosa-Bifosfato Carboxilasa/metabolismo , Ribulosa-Bifosfato Carboxilasa/química , Ribulosa-Bifosfato Carboxilasa/genética , Anhidrasas Carbónicas/metabolismo , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/química , Cianobacterias/metabolismo , Cianobacterias/genética , Cianobacterias/enzimología , Regulación Alostérica , Filogenia , Ribulosafosfatos/metabolismo , Modelos Moleculares , Multimerización de Proteína , Dióxido de Carbono/metabolismo , Especificidad por Sustrato , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química
4.
BMC Pulm Med ; 24(1): 228, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730395

RESUMEN

OBJECTIVE: To explore the association between PaCO2 and noninvasive ventilation (NIV) failure in patients with hypoxemic respiratory failure. METHODS: A retrospective study was performed in a respiratory ICU of a teaching hospital. Patients admitted to ICU between 2011 and 2019 were screened. We enrolled the patients with hypoxemic respiratory failure. However, patients who used NIV due to acute-on-chronic respiratory failure or heart failure were excluded. Data before the use of NIV were collected. Requirement of intubation was defined as NIV failure. RESULTS: A total of 1029 patients were enrolled in final analysis. The rate of NIV failure was 45% (461/1029). A nonlinear relationship between PaCO2 and NIV failure was found by restricted cubic splines (p = 0.03). The inflection point was 32 mmHg. The rate of NIV failure was 42% (224/535) in patients with PaCO2 >32 mmHg. However, it increased to 48% (237/494) in those with PaCO2 ≤ 32 mmHg. The crude and adjusted hazard ratio (HR) for NIV failure was 1.36 (95%CI:1.13-1.64) and 1.23(1.01-1.49), respectively, if the patients with PaCO2 >32 mmHg were set as reference. In patients with PaCO2 ≤ 32 mmHg, one unit increment of PaCO2 was associated with 5% reduction of NIV failure. However, it did not associate with NIV failure in patients with PaCO2 >32 mmHg. CONCLUSIONS: PaCO2 and NIV failure was nonlinear relationship. The inflection point was 32 mmHg. Below the inflection point, lower PaCO2 was associated with higher NIV failure. However, it did not associate with NIV failure above this point.


Asunto(s)
Dióxido de Carbono , Hipoxia , Ventilación no Invasiva , Insuficiencia Respiratoria , Insuficiencia del Tratamiento , Humanos , Insuficiencia Respiratoria/terapia , Insuficiencia Respiratoria/sangre , Estudios Retrospectivos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Hipoxia/sangre , Hipoxia/terapia , Dióxido de Carbono/sangre , Unidades de Cuidados Intensivos , Anciano de 80 o más Años , Análisis de los Gases de la Sangre
5.
Codas ; 36(3): e20220330, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38695436

RESUMEN

PURPOSE: The Awake Breathing Pattern Assessment (ABPA) is a prototypical clinical grid recently designed through an international consensus of Speech and Language Pathologists (SLPs) to categorize the awake and habitual breathing pattern during the orofacial myofunctional assessment. This cross-sectional study aims to explore the psychometric properties of the ABPA in a preschool population. METHODS: 133 children from 2;11 to 6 years old were assessed with the ABPA. The percentage of time spent breathing through the mouth was objectively measured by a CO2 sensor and used as a baseline measurement. We first performed a multivariate Latent Profile Analysis based on the CO2 measurement and a parental questionnaire to define the number of categories that best characterize the breathing pattern. Subsequently, we assessed the intra- and inter-rater reliability, internal consistency criterion validity, construct validity and sensitivity and specificity. RESULTS: The awake breathing pattern can best be described by two groups: nasal and mouth breathing. The ABPA, initially designed in three groups, was adjusted accordingly. This final version showed excellent intra-rater and inter-rater reliability. There was a significant correlation between the ABPA and the CO2 measurement. The ABPA showed a fair sensitivity and a good specificity. CONCLUSION: The reference tool based on CO2 data was used in children for the first time and was found to be reliable. The ABPA is a suitable tool for SLPs to confirm the diagnosis of mouth breathing in preschool children if more sensitive screening tools, like parental questionnaires, are used beforehand.


Asunto(s)
Respiración por la Boca , Humanos , Respiración por la Boca/diagnóstico , Respiración por la Boca/fisiopatología , Preescolar , Estudios Transversales , Reproducibilidad de los Resultados , Femenino , Masculino , Niño , Psicometría , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Vigilia/fisiología , Respiración , Dióxido de Carbono/análisis
6.
Pak J Pharm Sci ; 37(1(Special)): 235-243, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38747275

RESUMEN

Stimulus-responsive mesoporous silica nanoparticles (MSNs) have displayed great potentiality for controlled-release and targeted drug delivery. In the current work, a supercritical fluid method was utilized to successfully prepare cinnamon oil loaded into chitosan grafted MSNs (CO@CS-MSNs). The influencing factors of drug loads, such as pressure, temperature, impregnation time and depressure time, were investigated. The structure of CO@CS-MSNs was demonstrated with Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscopy (SEM), thermogravimetry (TG) as well as X-ray diffraction (XRD). The drug release assays in vitro at various pH conditions displayed that CO@CS-MSNs had an excellent pH-responsive release behavior, which confirmed that CO was loaded successfully into the CO@CS-MSNs. The findings indicated that the supercritical fluid approach is a non-destructive and efficient approach for stimulus-responsive MSNs, which is expected to further expand its application range.


Asunto(s)
Dióxido de Carbono , Quitosano , Cinnamomum zeylanicum , Liberación de Fármacos , Nanopartículas , Dióxido de Silicio , Quitosano/química , Dióxido de Silicio/química , Nanopartículas/química , Concentración de Iones de Hidrógeno , Dióxido de Carbono/química , Porosidad , Cinnamomum zeylanicum/química , Portadores de Fármacos/química , Aceites Volátiles/química , Aceites Volátiles/administración & dosificación , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Microscopía Electrónica de Rastreo , Preparaciones de Acción Retardada
7.
Funct Plant Biol ; 512024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38743837

RESUMEN

Cassava (Manihot esculenta Crantz), an important tropical crop, is affected by extreme climatic events, including rising CO2 levels. We evaluated the short-term effect of elevated CO2 concentration (ECO2 ) (600, 800 and 1000ppm) on the photosynthetic efficiency of 14 cassava genotypes. ECO2 significantly altered gaseous exchange parameters (net photosynthetic rate (P n ), stomatal conductance (g s ), intercellular CO2 (C i ) and transpiration (E )) in cassava leaves. There were significant but varying interactive effects between ECO2 and varieties on these physiological characteristics. ECO2 at 600 and 800ppm increased the P n rate in the range of 13-24% in comparison to 400ppm (ambient CO2 ), followed by acclimation at the highest concentration of 1000ppm. A similar trend was observed in g s and E . Conversely, C i increased significantly and linearly across increasing CO2 concentration. Along with C i , a steady increase in water use efficiency [WUEintrinsic (P n /g s ) and WUEinstantaneous (P n /E )] across various CO2 concentrations corresponded with the central role of restricted stomatal activity, a common response under ECO2 . Furthermore, P n had a significant quadratic relationship with the ECO2 (R 2 =0.489) and a significant and linear relationship with C i (R 2 =0.227). Relative humidity and vapour pressure deficit during the time of measurements remained at 70-85% and ~0.9-1.31kPa, respectively, at 26±2°C leaf temperature. Notably, not a single variety exhibited constant performance for any of the parameters across CO2 concentrations. Our results indicate that the potential photosynthesis can be increased up to 800ppm cassava varieties with high sink capacity can be cultivated under protected cultivation to attain higher productivity.


Asunto(s)
Dióxido de Carbono , Manihot , Fotosíntesis , Manihot/efectos de los fármacos , Manihot/fisiología , Fotosíntesis/efectos de los fármacos , Dióxido de Carbono/metabolismo , Hojas de la Planta/efectos de los fármacos , Transpiración de Plantas/efectos de los fármacos , Estomas de Plantas/fisiología , Estomas de Plantas/efectos de los fármacos , Genotipo , Agua
8.
Sci Rep ; 14(1): 11023, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744922

RESUMEN

Encroachment of vascular plants (VP) in temperate raised bogs, as a consequence of altered hydrological conditions and nutrient input, is widely observed. Effects of such vegetation shift on water and carbon cycles are, however, largely unknown and identification of responsible plant physiological traits is challenging. Process-based modelling offers the opportunity of gaining insights into ecosystem functioning beyond observations, and to infer decisive trait shifts of plant functional groups. We adapted the Soil-Vegetation-Atmosphere Transfer model pyAPES to a temperate raised bog site by calibration against measured peat temperature, water table and surface CO2 fluxes. We identified the most important traits determining CO2 fluxes by conducting Morris sensitivity analysis (MSA) under changing conditions throughout the year and simulated VP encroachment. We further investigated transferability of results to other sites by extending MSA to parameter ranges derived from literature review. We found highly variable intra-annual plant traits importance determining ecosystem CO2 fluxes, but only a partial shift of importance of photosynthetic processes from moss to VP during encroachment. Ecosystem respiration was dominated by peat respiration. Overall, carboxylation rate, base respiration rate and temperature sensitivity (Q10) were most important for determining bog CO2 balance and parameter ranking was robust even under the extended MSA.


Asunto(s)
Dióxido de Carbono , Ecosistema , Plantas , Estaciones del Año , Humedales , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análisis , Plantas/metabolismo , Suelo/química , Fotosíntesis , Ciclo del Carbono , Temperatura , Modelos Teóricos , Atmósfera
9.
Curr Opin Crit Care ; 30(3): 251-259, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38690954

RESUMEN

PURPOSE OF REVIEW: To describe current and near future developments and applications of CO2 kinetics in clinical respiratory and cardiovascular monitoring. RECENT FINDINGS: In the last years, we have witnessed a renewed interest in CO2 kinetics in relation with a better understanding of volumetric capnography and its derived parameters. This together with technological advances and improved measurement systems have expanded the monitoring potential of CO2 kinetics including breath by breath continuous end-expiratory lung volume and continuous noninvasive cardiac output. Dead space has slowly been gaining relevance in clinical monitoring and prognostic evaluation. Easy to measure dead space surrogates such as the ventilatory ratio have demonstrated a strong prognostic value in patients with acute respiratory failure. SUMMARY: The kinetics of carbon dioxide describe many relevant physiological processes. The clinical introduction of new ways of assessing respiratory and circulatory efficiency based on advanced analysis of CO2 kinetics are paving the road to a long-desired goal in clinical monitoring of critically ill patients: the integration of respiratory and circulatory monitoring during mechanical ventilation.


Asunto(s)
Capnografía , Dióxido de Carbono , Humanos , Dióxido de Carbono/análisis , Capnografía/métodos , Monitoreo Fisiológico/métodos , Respiración Artificial/métodos , Cinética , Gasto Cardíaco/fisiología , Biomarcadores , Espacio Muerto Respiratorio/fisiología
10.
PLoS Biol ; 22(5): e3002592, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38691548

RESUMEN

Stomata are pores on plant aerial surfaces, each bordered by a pair of guard cells. They control gas exchange vital for plant survival. Understanding how guard cells respond to environmental signals such as atmospheric carbon dioxide (CO2) levels is not only insightful to fundamental biology but also relevant to real-world issues of crop productivity under global climate change. In the past decade, multiple important signaling elements for stomatal closure induced by elevated CO2 have been identified. Yet, there is no comprehensive understanding of high CO2-induced stomatal closure. In this work, we assemble a cellular signaling network underlying high CO2-induced stomatal closure by integrating evidence from a comprehensive literature analysis. We further construct a Boolean dynamic model of the network, which allows in silico simulation of the stomatal closure response to high CO2 in wild-type Arabidopsis thaliana plants and in cases of pharmacological or genetic manipulation of network nodes. Our model has a 91% accuracy in capturing known experimental observations. We perform network-based logical analysis and reveal a feedback core of the network, which dictates cellular decisions in closure response to high CO2. Based on these analyses, we predict and experimentally confirm that applying nitric oxide (NO) induces stomatal closure in ambient CO2 and causes hypersensitivity to elevated CO2. Moreover, we predict a negative regulatory relationship between NO and the protein phosphatase ABI2 and find experimentally that NO inhibits ABI2 phosphatase activity. The experimental validation of these model predictions demonstrates the effectiveness of network-based modeling and highlights the decision-making role of the feedback core of the network in signal transduction. We further explore the model's potential in predicting targets of signaling elements not yet connected to the CO2 network. Our combination of network science, in silico model simulation, and experimental assays demonstrates an effective interdisciplinary approach to understanding system-level biology.


Asunto(s)
Arabidopsis , Dióxido de Carbono , Modelos Biológicos , Estomas de Plantas , Transducción de Señal , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/metabolismo , Estomas de Plantas/fisiología , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacología , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/fisiología , Simulación por Computador , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética
11.
Sci Rep ; 14(1): 10938, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740878

RESUMEN

Plant disease often increases with N, decreases with CO2, and increases as biodiversity is lost (i.e., the dilution effect). Additionally, all these factors can indirectly alter disease by changing host biomass and hence density-dependent disease transmission. Yet over long periods of time as communities undergo compositional changes, these biomass-mediated pathways might fade, intensify, or even reverse in direction. Using a field experiment that has manipulated N, CO2, and species richness for over 20 years, we compared severity of a specialist rust fungus (Puccinia andropogonis) on its grass host (Andropogon gerardii) shortly after the experiment began (1999) and twenty years later (2019). Between these two sampling periods, two decades apart, we found that disease severity consistently increased with N and decreased with CO2. However, the relationship between diversity and disease reversed from a dilution effect in 1999 (more severe disease in monocultures) to an amplification effect in 2019 (more severe disease in mixtures). The best explanation for this reversal centered on host density (i.e., aboveground biomass), which was initially highest in monoculture, but became highest in mixtures two decades later. Thus, the diversity-disease pattern reversed, but disease consistently increased with host biomass. These results highlight the consistency of N and CO2 as drivers of plant disease in the Anthropocene and emphasize the critical role of host biomass-despite potentially variable effects of diversity-for relationships between biodiversity and disease.


Asunto(s)
Biodiversidad , Biomasa , Dióxido de Carbono , Nitrógeno , Enfermedades de las Plantas , Dióxido de Carbono/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Nitrógeno/metabolismo , Basidiomycota/genética , Poaceae/microbiología
12.
Anal Chim Acta ; 1307: 342620, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719413

RESUMEN

BACKGROUND: Pharmacokinetic studies are pivotal in drug development, focusing on absorption, distribution, and excretion of active compounds. Effective sample preparation methods play a crucial role in these studies. Traditional techniques like protein precipitation and liquid-liquid extraction often involve toxic solvents and are time-consuming. Recently, deep eutectic solvent (DES) has emerged as an eco-friendly alternative due to its high efficiency, low cost, and low toxicity. This study introduces a novel sample pretreatment method using CO2-switchable DES in liquid-liquid microextraction (LLME) to enhance speed, accuracy, and sensitivity in complex biological samples analysis. RESULTS: A liquid-liquid microextraction sample pretreatment method based on switchable DES combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the analysis of urine and tissue samples. The method was optimized through systematic investigation of key parameters, including DES type, volume, molar ratio, pH, vortex time, gas purge time, and salt addition. The resulting procedure exhibited satisfying linearity (r2 ≥ 0.9958), good precision (RSD ≤6.01 %), desirable recovery (52.44%-98.12 %) and matrix effect (86.22%-119.30 %), and the accuracy and precision of stability were within the ±15 % limit. The proven methods were further applied to urinary excretion study and tissue distribution study of Nelumbinis plumula (NP) extract. The results indicated that the total cumulative excretion of liensinine, isoliensinine and neferine in urine within 240 h was 4.96 %, 0.66 % and 0.44 %, respectively. The tissue distribution study showed that alkaloids mainly distribute in liver, kidney, and spleen. SIGNIFICANCE: This research introduces a groundbreaking technique distinguished by its simplicity, speed, cost-effectiveness, and environmental friendliness. This approach, utilizing CO2-switchable DES as an extraction solvent for LLME, integrates deproteinization and removal of interfering molecules into a single step. This integration showcases its efficiency and convenience, demonstrating significant promise for various applications in the analysis of biological samples. Additionally, this study provides the first report on urinary excretion and tissue distribution of alkaloids from NP using a DES-LLME method. These findings offer valuable insights into the in vivo behavior of herbal medicine, enhancing understanding of pharmacological actions and facilitating clinical rational administration.


Asunto(s)
Dióxido de Carbono , Disolventes Eutécticos Profundos , Microextracción en Fase Líquida , Espectrometría de Masas en Tándem , Microextracción en Fase Líquida/métodos , Dióxido de Carbono/química , Disolventes Eutécticos Profundos/química , Animales , Distribución Tisular , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión , Masculino , Ratas , Ratas Sprague-Dawley
13.
PLoS One ; 19(5): e0302139, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38717995

RESUMEN

Cover crops have the potential to mitigate climate change by reducing negative impacts of agriculture on ecosystems. This study is first to quantify the net climate change mitigation impact of cover crops including land-use effects. A systematic literature and data review was conducted to identify major drivers for climate benefits and costs of cover crops in maize (Zea maize L.) production systems. The results indicate that cover crops lead to a net climate change mitigation impact (NCCMI) of 3.30 Mg CO2e ha-1 a-1. We created four scenarios with different impact weights of the drivers and all of them showing a positive NCCMI. Carbon land benefit, the carbon opportunity costs based on maize yield gains following cover crops, is the major contributor to the NCCMI (34.5% of all benefits). Carbon sequestration is the second largest contributor (33.8%). The climate costs of cover crops are mainly dominated by emissions from their seed production and foregone benefits due to land use for cover crops seeds. However, these two costs account for only 15.8% of the benefits. Extrapolating these results, planting cover crops before all maize acreage in the EU results in a climate change mitigation of 49.80 million Mg CO2e a-1, which is equivalent to 13.0% of the EU's agricultural emissions. This study highlights the importance of incorporating cover crops into sustainable cropping systems to minimize the agricultural impact to climate change.


Asunto(s)
Agricultura , Secuestro de Carbono , Cambio Climático , Productos Agrícolas , Ecosistema , Zea mays , Productos Agrícolas/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Agricultura/métodos , Agricultura/economía , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo
15.
Hum Vaccin Immunother ; 20(1): 2335722, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38698759

RESUMEN

We provide estimates for (I) annual herpes zoster (HZ) cases, (II) carbon costs related to healthcare utilization, and (III) annual carbon emissions due to HZ among ≥50 years of age (YOA) United States (US) population. We estimated the annual number of HZ cases in the US based on available incidence data and demographic data of individuals ≥50 YOA. Both the healthcare resource utilization (HCRU) associated with HZ cases and the unit carbon dioxide equivalent (i.e. CO2e) costs associated with each type of HCRU in the US were estimated based on literature and studies available online. The carbon footprint associated with HZ annually among US adults ≥50 YOA was estimated by multiplying the unit carbon estimates by the HCRU. In the US population aged ≥50 YOA in 2020 (i.e. approximately 118 million), approximately 1.1 million cases of HZ occur annually assuming no vaccination. Based on 2 sources of HCRU the average kgCO2e per HZ patient ranged from 61.0 to 97.6 kgCO2e, with values by age group ranging from 40.9 kgCO2e in patients aged 50-59 to 195.9 kgCO2e in patients ≥80 YOA. The total annual HZ associated carbon ranged between 67,000 and 107,000 tons of CO2e in the US population aged ≥50 YOA. The impact of HZ on carbon footprint in the US results in considerable greenhouse gas (GHG)emissions. Assuming no vaccination, the burden of HZ is projected to rise over the coming years with the aging populations consequently worsening its impact on GHG emissions. (Figure 1).


Asunto(s)
Huella de Carbono , Herpes Zóster , Humanos , Herpes Zóster/epidemiología , Estados Unidos/epidemiología , Anciano , Huella de Carbono/estadística & datos numéricos , Persona de Mediana Edad , Anciano de 80 o más Años , Masculino , Femenino , Incidencia , Dióxido de Carbono/análisis
16.
BMC Pulm Med ; 24(1): 217, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698379

RESUMEN

BACKGROUND: The effectiveness of high-flow nasal cannula (HFNC) therapy in patients with bronchiectasis experiencing hypercapnia remains unclear. Our aim was to retrospectively analyze the short-term outcomes of HFNC therapy in such patients, and to further explore the predictors of HFNC treatment failure in this particular patient population. METHODS: A retrospective review was conducted on patients with bronchiectasis who received HFNC (n = 70) for hypercapnia (arterial partial pressure of carbon dioxide, PaCO2 ≥ 45 mmHg) between September 2019 and September 2023. RESULTS: In the study population, 30% of patients presented with acidemia (arterial pH < 7.35) at baseline. Within 24 h of HFNC treatment, there was a significant reduction in PaCO2 levels by a mean of 4.0 ± 12.7 mmHg (95% CI -7.0 to -1.0 mmHg). Concurrently, arterial pH showed a statistically significant increase with a mean change of 0.03 ± 0.06 (95% CI 0.01 to 0.04). The overall hospital mortality rate in our study was 17.5%. The median length of hospital stay was 11.0 days (interquartile range [IQR] 8.0 to 16.0 days). Sub-analysis revealed no statistically significant differences in hospital mortality (19.0% vs. 20.4%, p = 0.896), length of hospital stay (median 14.0 days [IQR 9.0 to 18.0 days] vs. 10.0 days [IQR 7.0 to 16.0 days], p = 0.117) and duration of HFNC application (median 5.0 days [IQR 2.0 to 8.5 days] vs. 6.0 days [IQR 4.9 to 9.5 days], p = 0.076) between the acidemia group and the non-acidemia group (arterial pH ≥ 7.35). However, more patients in the non-acidemia group had do-not-intubate orders. The overall treatment failure rate for HFNC was 28.6%. Logistic regression analysis identified the APACHE II score (OR 1.24 per point) as the independent predictor of HFNC failure. CONCLUSIONS: In patients with bronchiectasis and hypercapnia, HFNC as an initial respiratory support can effectively reduce PaCO2 level within 24 h of treatment. A high APACHE II score has emerged as a prognostic indicator for HFNC treatment failure. These observations highlight randomized controlled trials to meticulously evaluate the efficacy of HFNC in this specific population.


Asunto(s)
Bronquiectasia , Cánula , Hipercapnia , Terapia por Inhalación de Oxígeno , Humanos , Estudios Retrospectivos , Hipercapnia/terapia , Masculino , Femenino , Bronquiectasia/terapia , Terapia por Inhalación de Oxígeno/métodos , Persona de Mediana Edad , Anciano , Mortalidad Hospitalaria , Tiempo de Internación/estadística & datos numéricos , Dióxido de Carbono , Resultado del Tratamiento
17.
Crit Care ; 28(1): 146, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693569

RESUMEN

PURPOSE: A systematic review and meta-analysis to evaluate the impact of extracorporeal carbon dioxide removal (ECCO2R) on gas exchange and respiratory settings in critically ill adults with respiratory failure. METHODS: We conducted a comprehensive database search, including observational studies and randomized controlled trials (RCTs) from January 2000 to March 2022, targeting adult ICU patients undergoing ECCO2R. Primary outcomes were changes in gas exchange and ventilator settings 24 h after ECCO2R initiation, estimated as mean of differences, or proportions for adverse events (AEs); with subgroup analyses for disease indication and technology. Across RCTs, we assessed mortality, length of stay, ventilation days, and AEs as mean differences or odds ratios. RESULTS: A total of 49 studies encompassing 1672 patients were included. ECCO2R was associated with a significant decrease in PaCO2, plateau pressure, and tidal volume and an increase in pH across all patient groups, at an overall 19% adverse event rate. In ARDS and lung transplant patients, the PaO2/FiO2 ratio increased significantly while ventilator settings were variable. "Higher extraction" systems reduced PaCO2 and respiratory rate more efficiently. The three available RCTs did not demonstrate an effect on mortality, but a significantly longer ICU and hospital stay associated with ECCO2R. CONCLUSIONS: ECCO2R effectively reduces PaCO2 and acidosis allowing for less invasive ventilation. "Higher extraction" systems may be more efficient to achieve this goal. However, as RCTs have not shown a mortality benefit but increase AEs, ECCO2R's effects on clinical outcome remain unclear. Future studies should target patient groups that may benefit from ECCO2R. PROSPERO Registration No: CRD 42020154110 (on January 24, 2021).


Asunto(s)
Dióxido de Carbono , Humanos , Dióxido de Carbono/análisis , Dióxido de Carbono/sangre , Intercambio Gaseoso Pulmonar/fisiología , Respiración Artificial/métodos , Insuficiencia Respiratoria/terapia
18.
Arq Bras Cardiol ; 121(4): e20230578, 2024.
Artículo en Portugués, Inglés | MEDLINE | ID: mdl-38695473

RESUMEN

BACKGROUND: Currently, excess ventilation has been grounded under the relationship between minute-ventilation/carbon dioxide output ( V ˙ E - V ˙ CO 2 ). Alternatively, a new approach for ventilatory efficiency ( η E V ˙ ) has been published. OBJECTIVE: Our main hypothesis is that comparatively low levels of η E V ˙ between chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD) are attainable for a similar level of maximum and submaximal aerobic performance, conversely to long-established methods ( V ˙ E - V ˙ CO 2 slope and intercept). METHODS: Both groups performed lung function tests, echocardiography, and cardiopulmonary exercise testing. The significance level adopted in the statistical analysis was 5%. Thus, nineteen COPD and nineteen CHF-eligible subjects completed the study. With the aim of contrasting full values of V ˙ E - V ˙ CO 2 and η V ˙ E for the exercise period (100%), correlations were made with smaller fractions, such as 90% and 75% of the maximum values. RESULTS: The two groups attained matched characteristics for age (62±6 vs. 59±9 yrs, p>.05), sex (10/9 vs. 14/5, p>0.05), BMI (26±4 vs. 27±3 Kg m2, p>0.05), and peak V ˙ O 2 (72±19 vs. 74±20 %pred, p>0.05), respectively. The V ˙ E - V ˙ CO 2 slope and intercept were significantly different for COPD and CHF (27.2±1.4 vs. 33.1±5.7 and 5.3±1.9 vs. 1.7±3.6, p<0.05 for both), but η V ˙ E average values were similar between-groups (10.2±3.4 vs. 10.9±2.3%, p=0.462). The correlations between 100% of the exercise period with 90% and 75% of it were stronger for η V ˙ E (r>0.850 for both). CONCLUSION: The η V ˙ E is a valuable method for comparison between cardiopulmonary diseases, with so far distinct physiopathological mechanisms, including ventilatory constraints in COPD.


FUNDAMENTO: Atualmente, o excesso de ventilação tem sido fundamentado na relação entre ventilação-minuto/produção de dióxido de carbono ( V ˙ E − V ˙ CO 2 ). Alternativamente, uma nova abordagem para eficiência ventilatória ( η E V ˙ ) tem sido publicada. OBJETIVO: Nossa hipótese principal é que níveis comparativamente baixos de η E V ˙ entre insuficiência cardíaca crônica (ICC) e doença pulmonar obstrutiva crônica (DPOC) são atingíveis para um nível semelhante de desempenho aeróbico máximo e submáximo, inversamente aos métodos estabelecidos há muito tempo (inclinação V ˙ E − V ˙ CO 2 e intercepto). MÉTODOS: Ambos os grupos realizaram testes de função pulmonar, ecocardiografia e teste de exercício cardiopulmonar. O nível de significância adotada na análise estatística foi 5%. Assim, dezenove indivíduos elegíveis para DPOC e dezenove indivíduos elegíveis para ICC completaram o estudo. Com o objetivo de contrastar valores completos de V ˙ E − V ˙ CO 2 e η E V ˙ para o período de exercício (100%), correlações foram feitas com frações menores, como 90% e 75% dos valores máximos. RESULTADOS: Os dois grupos tiveram características correspondentes para a idade (62±6 vs 59±9 anos, p>.05), sexo (10/9 vs 14/5, p>0,05), IMC (26±4 vs 27±3 Kg m2, p>0,05), e pico V ˙ O 2 (72±19 vs 74±20 % pred, p>0,05), respectivamente. A inclinação V ˙ E − V ˙ CO 2 e intercepto foram significativamente diferentes para DPOC e ICC (207,2±1,4 vs 33,1±5,7 e 5,3±1,9 vs 1,7±3,6, p<0,05 para ambas), mas os valores médios da η E V ˙ foram semelhantes entre os grupos (10,2±3,4 vs 10,9±2,3%, p=0,462). As correlações entre 100% do período do exercício com 90% e 75% dele foram mais fortes para η E V ˙ (r>0,850 para ambos). CONCLUSÃO: A η E V ˙ é um método valioso para comparação entre doenças cardiopulmonares, com mecanismos fisiopatológicos até agora distintos, incluindo restrições ventilatórias na DPOC.


Asunto(s)
Prueba de Esfuerzo , Insuficiencia Cardíaca , Consumo de Oxígeno , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Masculino , Persona de Mediana Edad , Femenino , Insuficiencia Cardíaca/fisiopatología , Prueba de Esfuerzo/métodos , Anciano , Consumo de Oxígeno/fisiología , Pruebas de Función Respiratoria , Tolerancia al Ejercicio/fisiología , Ventilación Pulmonar/fisiología , Valores de Referencia , Ecocardiografía , Enfermedad Crónica , Dióxido de Carbono
19.
Proc Natl Acad Sci U S A ; 121(21): e2316497121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38739807

RESUMEN

Decreased production of crops due to climate change has been predicted scientifically. While climate-resilient crops are necessary to ensure food security and support sustainable agriculture, predicting crop growth under future global warming is challenging. Therefore, we aimed to assess the impact of realistic global warming conditions on rice cultivation. We developed a crop evaluation platform, the agro-environment (AE) emulator, which generates diverse environments by implementing the complexity of natural environmental fluctuations in customized, fully artificial lighting growth chambers. We confirmed that the environmental responsiveness of rice obtained in the fluctuation of artificial environments is similar to those exhibited in natural environments by validating our AE emulator using publicly available meteorological data from multiple years at the same location and multiple locations in the same year. Based on the representative concentration pathway, real-time emulation of severe global warming unveiled dramatic advances in the rice life cycle, accompanied by a 35% decrease in grain yield and an 85% increase in quality deterioration, which is higher than the recently reported projections. The transcriptome dynamism showed that increasing temperature and CO2 concentrations synergistically changed the expression of various genes and strengthened the induction of flowering, heat stress adaptation, and CO2 response genes. The predicted severe global warming greatly alters rice environmental adaptability and negatively impacts rice production. Our findings offer innovative applications of artificial environments and insights for enhancing varietal potential and cultivation methods in the future.


Asunto(s)
Calentamiento Global , Oryza , Oryza/crecimiento & desarrollo , Oryza/genética , Cambio Climático , Productos Agrícolas/crecimiento & desarrollo , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análisis , Agricultura/métodos , Regulación de la Expresión Génica de las Plantas , Temperatura , Transcriptoma
20.
Environ Sci Technol ; 58(19): 8299-8312, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38690832

RESUMEN

Accurate estimates of fossil fuel CO2 (FFCO2) emissions are of great importance for climate prediction and mitigation regulations but remain a significant challenge for accounting methods relying on economic statistics and emission factors. In this study, we employed a regional data assimilation framework to assimilate in situ NO2 observations, allowing us to combine observation-constrained NOx emissions coemitted with FFCO2 and grid-specific CO2-to-NOx emission ratios to infer the daily FFCO2 emissions over China. The estimated national total for 2016 was 11.4 PgCO2·yr-1, with an uncertainty (1σ) of 1.5 PgCO2·yr-1 that accounted for errors associated with atmospheric transport, inversion framework parameters, and CO2-to-NOx emission ratios. Our findings indicated that widely used "bottom-up" emission inventories generally ignore numerous activity level statistics of FFCO2 related to energy industries and power plants in western China, whereas the inventories are significantly overestimated in developed regions and key urban areas owing to exaggerated emission factors and inexact spatial disaggregation. The optimized FFCO2 estimate exhibited more distinct seasonality with a significant increase in emissions in winter. These findings advance our understanding of the spatiotemporal regime of FFCO2 emissions in China.


Asunto(s)
Contaminantes Atmosféricos , Dióxido de Carbono , Combustibles Fósiles , China , Dióxido de Carbono/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente
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