The effects of seasonal variability of precipitation and vegetation cycle on enhanced weathering for carbon sequestration

Enhanced weathering (EW) is one of the most promising technologies for sequestering atmospheric carbon. It consists on accelerating the chemical weathering fluxes naturally occurring in soils, by means of the addition of silicate minerals (i.e., forsterite), used as amendments, to the soil. If crushed into micrometer-sized particles, these minerals are characterized by high dissolution rates, that may be further improved under high soil water content and low pH conditions. Before actually applying EW technique at the global scale for carbon sequestration, an in-depth characterization of weathering and carbon sequestration rates, under different environmental conditions, is needed, also looking at correlated beneficial/detrimental effects. In this context, modeling approaches may play a pivotal role, since they allow to achieve this goal without affording costs required by laboratory and field experiments. The present study describes the application of a dynamic mass balance model connecting ecohydrological, biogeochemical and olivine dissolution dynamics. The model is composed of four connected components and is solved through an explicit system of eight mass balance total differential equations and an implicit one having 22 algebraic equations. In this study, the model is applied to two sites in Italy (i.e., Sicily, in the south and the Padan plain, in the north) and two in the USA (i.e., California, in the south-west and Iowa, in the north-central area). The most common crops for the case studies, i.e., wheat for Sicily and California and corn for the Padan plain and Iowa are here considered, along with the most frequent soil types, namely the clay loam for Sicily and California and the silty clay loam for the Padan plain and Iowa. Maps of lithological composition of bedrocks and spatial distributions of soil pH have been also used to calibrate the background weathering flux, responsible of the H+ consume from all the minerals naturally present in the soil. Apart from deriving the most suitable locations, among those presented, providing the highest weathering and carbon sequestration rates, these simulations allow to assess the role of different climate, crop and soil types on EW dynamics, in perspective to find the combination that maximizes the CO2 sequestration

Using very high resolution (VHR) imagery within a GEOBIA framework for gully mapping: An application to the Calhoun Critical Zone Observatory

Gully erosion is a form of accelerated erosion that may affect soil productivity, restrict land use, and lead to an increase of risk to infrastructure. Accurate mapping of these landforms can be difficult because of the presence of dense canopy and/or the wide spatial extent of some gullies. Even where possible, mapping of gullies through conventional field surveying can be an intensive and expensive activity. The recent widespread availability of very high resolution (VHR) imagery has led to remarkable growth in the availability of terrain information, thus providing a basis for the development of new methodologies for analyzing Earth’s surfaces. This work aims to develop a geographic object-based image analysis to detect and map gullies based on VHR imagery. A 1-meter resolution LIDAR DEM is used to identify gullies. The tool has been calibrated for two relatively large gullies surveyed in the Calhoun Critical Zone Observatory (CCZO) area in the southeastern United States. The developed procedure has been applied and tested on a greater area, corresponding to the Holcombe’s Branch watershed within the CCZO. Results have been compared to previous works conducted over the same area, demonstrating the consistency of the developed procedure

Individuazione dei trend di pioggia per la Sicilia utilizzando un approccio multiscala basato sulla regressione a quantili

Uno degli argomenti più attuali e controversi è se, negli ultimi decenni, le piogge intense siano diventate più frequenti come possibile effetto dei cambiamenti climatici. La centralità del tema è giustificata dalle gravi conseguenze che l’intensificarsi di questi fenomeni, in frequenza e magnitudo, potrebbe indurre a livello sociale ed economico. Basti pensare alle “flash flood”, spesso causate da eventi di precipitazione con una forte componente convettiva, che in ambito urbano mettono in crisi i sistemi di drenaggio arrecando rilevanti danni e, purtroppo, anche perdite di vite umane. La Sicilia è stata spesso monitorata con l’obiettivo di individuare delle mutazioni significative del ciclo idrologico e, di conseguenza, dei fenomeni precipitativi, potenzialmente imputabili ad un clima che cambia. Ad oggi, l’identificazione di questi trend è principalmente incentrata sull’analisi dei valori estremi di pioggia, come ad esempio i massimi annuali o i valori eccedenti una determinata soglia, attraverso l’utilizzo di differenti test statistici, tra i quali spicca il test di Mann-Kendall. Tuttavia, l’analisi di un campione limitato, seppur significativo, di valori può portare a trascurare dei segnali nascosti nella totalità dei dati osservati. A partire da questa considerazione, il presente lavoro ha come obiettivo lo studio dei trend di precipitazione attraverso lo strumento della regressione a quantili, analizzando serie temporali continue di dati registrate da circa 80 stazioni pluviografiche della rete regionale SIAS nel periodo 2002 – 2019. In particolare, lo studio è stato condotto considerando un ampio ventaglio di durate dei fenomeni, a partire dalla risoluzione temporale delle serie temporali (10 minuti) fino a giungere all’aggregazione nelle 24 ore, e per differenti valori dei quantili (da 0.2 fino a 0.99). Il principale vantaggio della regressione a quantili è che nessun dato valido viene scartato ai fini dell’analisi, ma a tutti i valori che eccedono il quantile considerato viene assegnato un peso ad esso proporzionale, mentre il peso è complementare al valore del quantile nel caso dei valori inferiori alla soglia. I risultati hanno evidenziato che, soprattutto per i quantili più elevati (0.90, 0.95 e 0.99), vi sia un’evidente dipendenza tra i trend positivi e la durata della precipitazione. In particolare, vi è un aumento del numero di stazioni che mostrano un incremento significativo dell’intensità di pioggia oraria passando dalla durata di 24 ore fino a quelle sub-orarie. Ad esempio, circa il 50% delle stazioni considerate mostra un trend positivo per la durata di 10 minuti e per i quantili 0.95 e 0.99. Al contrario, considerando il quantile 0.2 è possibile riscontrare un aumento del numero di stazioni caratterizzate da decrementi significativi di intensità di pioggia oraria con la durata. Oltre alla dipendenza con la durata, è stata anche analizzata la variabilità spaziale dei trend di precipitazione attraverso l’indice di autocorrelazione di Moran, nella variante globale e locale. Dall’applicazione di quest’ultimo è stato riscontrato che la Sicilia sud-orientale è interessata da un aumento significativo dei trend di pioggia, soprattutto per la durata di 10 minuti

Melatonin and the cardiovascular system in animals: systematic review and meta-analysis

Melatonin, a hormone released by the pineal gland, demonstrates several effects on the cardiovascular system. Herein, we performed a systematic review and meta-analysis to verify the effects of melatonin in an experimental model of myocardial infarction. We performed a systematic review according to PRISMA recommendations and reviewed MEDLINE, Embase, and Cochrane databases. Only articles in English were considered. A systematic review of the literature published between November 2008 and June 2019 was performed. The meta-analysis was conducted using the RevMan 5.3 program provided by the Cochrane Collaboration. In total, 858 articles were identified, of which 13 were included in this review. The main results of this study revealed that melatonin benefits the cardiovascular system by reducing infarct size, improving cardiac function according to echocardiographic and hemodynamic analyses, affords antioxidant effects, improves the rate of apoptosis, decreases lactate dehydrogenase activity, enhances biometric analyses, and improves protein levels, as analyzed by western blotting and quantitative PCR. In the meta-analysis, we observed a statistically significant decrease in infarct size (mean difference [MD], -20.37 [-23.56, -17.18]), no statistical difference in systolic pressure (MD, -1.75 [-5.47, 1.97]), a statistically significant decrease in lactate dehydrogenase in animals in the melatonin group (MD, -4.61 [-6.83, -2.40]), and a statistically significant improvement in the cardiac ejection fraction (MD, -8.12 [-9.56, -6.69]). On analyzing potential bias, we observed that most studies presented a low risk of bias; two parameters were not included in the analysis, and one parameter had a high risk of bias. Melatonin exerts several effects on the cardiovascular system and could be a useful therapeutic target to combat various cardiovascular diseases

Trans-visceral migration of retained surgical gauze as a cause of intestinal obstruction: a case report

<p>Abstract</p> <p>Introduction</p> <p>A retained surgical sponge in the abdomen is uncommon although it is likely that this finding is underreported in the medical literature. The intravisceral migration of retained surgical gauze is even rarer, as demonstrated by the very few cases reported.</p> <p>Case presentation</p> <p>Three years after undergoing anterior resection of the rectum, a 75-year-old man presented with symptoms of small bowel obstruction. Plain abdominal radiography and CT showed a radio-opaque marker; a foreign body was suspected, probably a piece of retained surgical gauze. An ileotomy of about 5 cm. was performed to confirm this diagnosis and remove the gauze.</p> <p>Conclusion</p> <p>Although rare, retained gauze in the abdomen is a complication of surgery. The authors consider that this event may be more frequent than it appears from reports in the literature, probably because of its medico-legal implications. If all such cases were reported, it would be possible to estimate their exact number, classify the occurrence as a possible surgical complication and thus modify its medico-forensic consequences.</p

Dupilumab in the treatment of severe uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP): A multicentric observational Phase IV real-life study (DUPIREAL)

Background Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with significant morbidity and reduced health-related quality of life. Findings from clinical trials have demonstrated the effectiveness of dupilumab in CRSwNP, although real-world evidence is still limited. Methods This Phase IV real-life, observational, multicenter study assessed the effectiveness and safety of dupilumab in patients with severe uncontrolled CRSwNP (n = 648) over the first year of treatment. We collected data at baseline and after 1, 3, 6, 9, and 12 months of follow-up. We focused on nasal polyps score (NPS), symptoms, and olfactory function. We stratified outcomes by comorbidities, previous surgery, and adherence to intranasal corticosteroids, and examined the success rates based on current guidelines, as well as potential predictors of response at each timepoint. Results We observed a significant decrease in NPS from a median value of 6 (IQR 5–6) at baseline to 1.0 (IQR 0.0–2.0) at 12 months (p &lt; .001), and a significant decrease in Sino-Nasal Outcomes Test-22 (SNOT-22) from a median score of 58 (IQR 49–70) at baseline to 11 (IQR 6–21; p &lt; .001) at 12 months. Sniffin' Sticks scores showed a significant increase over 12 months (p &lt; .001) compared to baseline. The results were unaffected by concomitant diseases, number of previous surgeries, and adherence to topical steroids, except for minor differences in rapidity of action. An excellent-moderate response was observed in 96.9% of patients at 12 months based on EPOS 2020 criteria. Conclusions Our findings from this large-scale real-life study support the effectiveness of dupilumab as an add-on therapy in patients with severe uncontrolled CRSwNP in reducing polyp size and improving the quality of life, severity of symptoms, nasal congestion, and smell

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

The role of hydrological processes on enhanced weathering for carbon sequestration in soils in tropical areas

To mitigate global warming, a noticeable research effort is being devoted to NCS (Natural Climate Solutions) as means to reduce greenhouse gas emissions or sequester carbon within the oceans or terrestrial environments by exploiting natural processes. Enhanced weathering is a NCS that aims to increase the weathering reaction rates of silicate minerals, by amending soils with crushed reactive minerals. Various studies have shown that this technique is favored by hot and humid climates (i.e., tropical ecosystems), since weathering reactions are mostly effective under high temperature and soil moisture. Despite olivine dissolution dynamics in laboratory conditions are quite well known, understanding and modeling them in field is still a challenge. Indeed, apart from some pot experiments involving soils of agricultural fields, only few weathering models are available. Given the urgency of the problem, models play a very important role for extrapolating results of laboratory and field experiments in both time and space, as well as for quantifying the impact of hydroclimatic fluctuations on the involved biogeochemical processes. The present study explores the role of hydrological processes on long-term Forsterite dissolution, a highly reactive silicate mineral also known as Mg-olivine or simply olivine. Toward this goal, we present a novel dynamic mass balance model coupling ecohydrological and biogeochemical dynamics, including mineral dissolution. Results under different climate scenarios highlight that hydrological fluctuations lead to hysteretic patterns of weathering rate with soil moisture, meaning that the process maintains a memory of past events (i.e., dry or wet periods). The model allows to explore the twofold role of organic matter on enhanced weathering; indeed, while its decomposition is a source of CO2, organic matter also increases the soil CEC, thus buffering changes in soil pH. Carbon sequestration and nutrients availability due to enhanced weathering are quantified, in this study, as a function of MAP (Mean Annual Precipitation). Average CO2 that reacts with olivine can exceed 40 t ha-1 y-1 for MAP higher than 2000 mm, condition that is always reached in the tropics. This CO2 can be found as dissolved in soil water in the form of bicarbonate (HCO3-) and carbonate (CO32-) ions and will be leached away from the domain, eventually reaching the ocean. In presence of tropical climate olivine application also leads to an increase of soil pH and nutrients availability, especially calcium and magnesium, which in turn can enhance plant productivity. This study paves the way for a potential integration of enhanced weathering in agroecosystem management practices, especially in humid tropical regions since these are characterized by high MAP and temperature