Free Air Research Articles

The benefits of interval appendectomy and risk factors for nonoperative management failure in the therapeutic strategy for complicated appendicitis.

Emergency surgery (ES) for complicated appendicitis (CA) is associated with high morbidity. Interval appendectomy (IA) decreases this rate; however, nonoperative management (NOM) is not always successful. Some patients require unplanned ES due to NOM failure (IA failure: IA-F). This study aimed to verify the benefits of IA and to evaluate the risk factors for NOM failure. Patients diagnosed with CA who underwent surgery between January 2012 and December 2021 were included in this study. We compared the surgical outcomes of the ES group with those of the IA success (IA-S) and IA-F groups. We also analyzed 14 factors that predicted NOM failure. Among 302 patients, the rate of severe complications (Clavien-Dindo grade ≥ III) was significantly higher in the ES group (N = 165) than in the IA-S group (N = 102). The rates were equal between the ES (N = 165) and IA-F (N = 35) groups. NOM was successful in 110 patients and failed in 27. Lack of abscesses, comorbidities, high WBC count, and free air were independent risk factors for NOM failure. Considering the benefits of IA and the non-inferior surgical outcomes of IA-F compared to ES, IA is a good therapeutic strategy for CA. However, in patients exhibiting four independent risk factors for NOM failure, careful monitoring of unplanned ES is necessary.

Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

Acorn production in oak (Quercus spp.) shows considerable inter-annual variation, known as masting, which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each year. Anthropogenic emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the ‘fertilisation effect’ that leads to enhanced photosynthesis. To examine if acorn production in mature woodland communities will be affected by further increase in CO2, the contents of litter traps from a Free Air Carbon Enrichment (FACE) experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak (Quercus robur L.) at different stages of development and their predation levels under ambient and elevated CO2 concentrations. Inter-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021, with the greatest numbers of mature acorns in 2015, 2017 and 2020 but almost none in 2018. The numbers of flowers, enlarged cups, immature acorns, empty acorn cups, and galls in the litter traps also varied amongst years; comparatively high numbers of enlarged cups were recorded in 2018, suggesting Q. robur at this site is a fruit maturation masting species (i.e., the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly). Raising the atmospheric CO2 concentration by 150 μL L−1, from early 2017, increased the numbers of immature acorns, and all acorn evidence (empty cups + immature acorns + mature acorns) detected in the litter traps compared to ambient controls by 2021, but did not consistently affect the numbers of flowers, enlarged cups, empty cups, or mature acorns. The number of flowers in the elevated CO2 plots’ litter traps was greater in 2018 than 2017, one year after CO2 enrichment began, whereas numbers declined in ambient plots. Enrichment with CO2 also increased the number of oak knopper galls (Andricus quercuscalicis Burgsdorf). We conclude that elevated CO2 increased the occurrence of acorns developing from flowers, but the putative benefit to mature acorn numbers may have been hidden by excessive pre- and/or post-dispersal predation. There was no evidence that elevated CO2 altered masting behaviour.

A perforation of a duodenal diverticulum in a 97-year-old patient after total gastrectomy and Roux-en-Y reconstruction: a case report.

Most duodenal diverticula (DD) are asymptomatic and rarely develop perforations. Perforation is the most serious complication of DD and often requires emergency surgery. A 97-year-old woman who had undergone total gastrectomy and Roux-en-Y reconstruction 30years ago was referred to our department with chief complaints of abdominal pain and fever during her hospitalization after femoral neck fracture surgery in the orthopedic department. Contrast-enhanced computed tomography showed free air and residue in the abdominal cavity and right retroperitoneum, and an emergency laparotomy was performed. The abdominal cavity was mildly contaminated, and a 6-cm DD with a 1-cm perforation in the wall of the diverticulum on the contralateral side of the mesentery of the duodenum was found. Diverticulectomy and duodenal closure were performed and a drainage tube was placed. The patient experienced no complications and was transferred to the orthopedic department on postoperative day 10. Reports of perforation of DD after gastrectomy are very rare. Particular attention should be paid to perforation of DD after Billroth-II and Roux-en-Y reconstructions as they involve the formation of a duodenal stump that differs from the normal anatomy and may be highly invasive surgical procedures, depending on the degree of inflammation and fistula formation.

Activating reversible carbonate reactions in Nasicon solid electrolyte-based Na-air battery via in-situ formed catholyte

Out of practicality, ambient air rather than oxygen is preferred as a fuel in electrochemical systems, but CO2 and H2O present in air cause severe irreversible reactions, such as the formation of carbonates and hydroxides, which typically degrades performance. Herein, we report on a Na-air battery enabled by a reversible carbonate reaction (Na2CO3·xH2O, x = 0 or 1) in Nasicon solid electrolyte (Na3Zr2Si2PO12) that delivers a much higher discharge potential of 3.4 V than other metal-air batteries resulting in high energy density and achieves > 86 % energy efficiency at 0.1 mA cm−2 over 100 cycles. This cell design takes advantage of moisture in ambient air to form an in-situ catholyte via the deliquescent property of NaOH. As a result, not only reversible electrochemical reaction of Na2CO3·xH2O is activated but also its kinetics is facilitated. Our results demonstrate the reversible use of free ambient air as a fuel, enabled by the reversible electrochemical reaction of carbonates with a solid electrolyte.

Warming-Induced Stimulation of Soil N2O Emissions Counteracted by Elevated CO2 from Nine-Year Agroecosystem Temperature and Free Air Carbon Dioxide Enrichment.

Globally, agricultural soils account for approximately one-third of anthropogenic emissions of the potent greenhouse gas and stratospheric ozone-depleting substance nitrous oxide (N2O). Emissions of N2O from agricultural soils are affected by a number of global change factors, such as elevated air temperatures and elevated atmospheric carbon dioxide (CO2). Yet, a mechanistic understanding of how these climatic factors affect N2O emissions in agricultural soils remains largely unresolved. Here, we investigate the soil N2O emission pathway using a 15N tracing approach in a nine-year field experiment using a combined temperature and free air carbon dioxide enrichment (T-FACE). We show that the effect of CO2 enrichment completely counteracts warming-induced stimulation of both nitrification- and denitrification-derived N2O emissions. The elevated CO2 induced decrease in pH and labile organic nitrogen (N) masked the stimulation of organic carbon and N by warming. Unexpectedly, both elevated CO2 and warming had little effect on the abundances of the nitrifying and denitrifying genes. Overall, our study confirms the importance of multifactorial experiments to understand N2O emission pathways from agricultural soils under climate change. This better understanding is a prerequisite for more accurate models and the development of effective options to combat climate change.

[Diagnostic value of identifying location and amount of free gas in the abdominal cavity by multidetector computed tomography in patients with acute gastrointestinal perforation].

Objective: To evaluate the relationships between the location and extent of diffusion of free intraperitoneal air by multi-slice spiral CT (MSCT) and between the location and size of acute gastrointestinal perforation. Methods: This was a descriptive case series. We examined abdominal CT images of 33 patients who were treated for intraoperatively confirmed gastrointestinal perforation (excluding appendiceal perforation) in the Department of General Surgery, Nanfang Hospital between January and September 2022. We identified five locations of intraperitoneal air: the subphrenic space, hepatic portal space, mid-abdominal wall, mesenteric space, and pelvic cavity. We allocated the 33 patients to an upper gastrointestinal perforation (n=23) and lower gastrointestinal perforation group (n=10) base on intraoperative findings and analyzed the relationships between the locations of free gas and of gastrointestinal perforation. Additionally, we established two models for analyzing the extent of diffusion of free gas in the abdominal cavity and constructed receiver operating characteristic (ROC) curves to analyze the relationships between the two models and the size of the gastrointestinal perforation. Results: In the upper gastrointestinal perforation group, free gas was located around the hepatic portal area in 91.3% (21/23) of patients: this is a significantly greater proportion than that found in the lower gastrointestinal perforation group (5/10) (P=0.016). In contrast, free gas was located in the mesenteric interspace in 8/10 patients in the lower gastrointestinal perforation group; this is a significantly greater proportion than was found in the upper gastrointestinal perforation group (8.7%, 2/23) (P<0.010). The sensitivity of diagnosis of upper gastrointestinal perforation base on the presence of hepatic portal free gas was 84.8% and the specificity 71.4%. Further, the sensitivity of diagnosis of lower gastrointestinal perforation base on the presence of mesenteric interspace free gas was 80.0% and the specificity 91.3%. The rates of presence of free gas in the subdiaphragmatic area, mid-abdominal wall, and pelvic cavity did not differ significantly between the two groups (all P>0.05). Receiver operating characteristic curves showed that when free gas was present in four or more of the studied locations in the abdominal cavity, the optimal cutoff for perforation diameter was 2 cm, the corresponding sensitivity 66.7%, and the specificity 100%, suggesting that abdominal free gas diffuses extensively when the diameter of the perforation is >2 cm. Another model revealed that when free gas is present in three or more of the studied locations, the optimal cutoff for perforation diameter is 1 cm, corresponding to a sensitivity of 91.7% and specificity of 76.2%; suggesting that free gas is relatively confined in the abdominal cavity when the diameter of the perforation is <1 cm. Conclusion: Identifying which of five locations in the abdominal cavity contains free intraperitoneal air by examining MSCT images can be used to assist in the diagnosis of the location and size of acute gastrointestinal perforations.

Better estimation of evapotranspiration and transpiration using an improved modified Priestly-Taylor model based on a new parameter of leaf senescence in a rice field

Evapotranspiration (ET) is at the heart of the global water, energy, and carbon cycles. As ET is difficult and expensive to measure, it is crucial to develop estimation models that can be widely applied. Currently, an improved Priestley-Taylor (PT) model considers soil moisture stress, temperature constraints, and leaf senescence; however, its parameter (fs) for simulating crop senescence is based on empirical values, making it difficult to apply to different varieties and complex external conditions and thus challenging to generalize. We improved the parameters fs in the original model based on the chlorophyll decomposition that accompanies crop senescence through easily observable SPAD values (Soil-Plant Analysis Development readings) in the field. We validated the improved model by obtaining ET of different rice varieties in 2022 and 2023 using the energy balance residual method at the Free Air Concentration Enrichment Experimental (FACE) Facility located in Yangzhou City, China. The results showed that the simulation of leaf senescence using SPAD values was feasible and could be extended to different varieties. The new model using improved leaf senescence parameter for estimating ET and transpiration (T) in three plots (2022 and 2023) exhibited slightly enhanced accuracy, particularly at the later stages of crop growth. Moreover, the higher the T/ET ratio of the cropland, the more significant the improvement. This new development enhances the ability of PT models to estimate ET and T using readily available field observations and provides some suggestions for wider application in the field for other crop species.

A Case of Post-Colonoscopy Intra/Extraperitoneal Free Air: Is Surgical Treatment Always Necessary?

Colonoscopy-related colonic perforation may occur through pneumatic or mechanical impact, or due to various therapeutic procedures. Mucosal herniation may also develop because of the increase in post-air insufflation pressure. This condition may render the mucosa air-permeable without a distinct focal perforation point.&#x0D; A 63-year-old female patient, who had had surgery for malign rectal neoplasm five years before and followed-up for radiation proctitis, presented to the emergency department three days after she had control colonoscopy with complaints of a gradually deteriorating facial and cervical swelling along with respiratory distress that developed a day after the procedure. The results of the patient’s analyses revealed that she had colonoscopy-related pneumoperitoneum, pneumoretroperitoneum, pneumomediastinum, cervical and facial subcutaneous emphysema. Medical follow-up was planned for the patient since there were no signs of peritonitis in her physical examination, her overall condition was well, and because a long time had passed after the procedure. The patient was discharged after a two-day follow-up with no problems.&#x0D; Colonoscopy-related intraperitoneal or extraperitoneal free air can both be seen immediately during the procedure and it can develop a long time after the procedure as well. Unnecessary surgical procedures can be prevented through medical follow-up under close monitoring in such patients particularly if they do not have peritonitis signs or symptoms and their overall condition is well.

Oliviculture and Viticulture Crop Byproducts Use for Peat Partial Substitution for Carnation Production

The intensive cultivation of olive trees and grapevines in the Mediterranean region not only results in large yields but also generate wastes, with high restrictions on their impact on people’s well-being and the environment. The current study sought to investigate the potential use of olive-mill waste (OW), grape-mill waste (GW) and their mixtures (OW + GW) at different levels (0%, 5%, 10% and 20% v/v) for partial peat substitution in the production of carnation (Dianthus caryophyllus L.) plants. The presence of OW, GW and OW + GW wastes raised the pH, the electrical conductivity, the content of organic matter and mineral content in substrate mixtures, while they decreased the total porosity and the available free air. The use of OW had more negative impacts than GW, while the OW + GW mixture alleviated, to some extent, the negative OW impacts. The use of high levels of residues decreased plant growth, chlorophyll content and mineral accumulation in plant tissue due to inappropriate growing media properties. The increased OW presence caused oxidative stress to the plants, as verified by the increased malondialdehyde and hydrogen peroxide content. This resulted in an upsurge in the total phenolics. However, GW presence did not impact any oxidative stress. It can be suggested that 10% OW, 10% GW or 20% OW + GW can be used in growing media, as they resulted in suitable plant growth. To ensure sufficient yields, nevertheless, the growing media’s characteristics also need to be enhanced.

Successful management of splenic artery dissection after sigmoid colon perforation in vascular Ehlers–Danlos syndrome

BackgroundEhlers–Danlos syndrome (EDS) is a genetic disorder that causes fragility of the systemic connective tissues. Of the 13 subtypes, vascular EDS (vEDS) is associated with abnormalities in collagen production, resulting in arterial rupture and intestinal perforation. Herein, we report the case of a man with confirmed vEDS who survived a ruptured dissected splenic artery aneurysm triggered by perforation of the sigmoid colon.Case presentationA 48-year-old man presented to our hospital with sudden severe lower abdominal pain. The patient was genetically diagnosed with vEDS at the age of 43 years. Abdominal computed tomography (CT) showed fluid and free air surrounding the sigmoid colon. These findings suggested sigmoid colon perforation, and emergency surgery was needed. Hartmann’s procedure was performed. The resected specimen showed a 2-cm-sized depression around the perforation. Histopathological findings showed an abscess and exudate in the serosa of the perforation and thinning of the intrinsic muscular layer in the depressed area. The patient was doing well postoperatively; however, on the ninth postoperative day, sudden upper abdominal pain developed. CT revealed an intra-abdominal hemorrhage due to rupture of a dissecting splenic artery aneurysm. The aneurysm was not observed on preoperative CT and was distant from the surgical site. Urgent transcatheter arterial embolization was performed. Although embolization of the splenic artery was attempted during the procedure, the arterial dissection spread to the common hepatic artery. Moreover, the proper hepatic and gastroduodenal arteries were poorly visualized, probably due to vasospasm. Although complications associated with extensive embolization were a concern, embolization of the splenic and common hepatic arteries was necessary to save the patient’s life. After embolization, angiography showed that the left hepatic blood flow was maintained from the inferior phrenic artery, and the right hepatic inflow was maintained from the superior mesenteric artery via the peribiliary vascular plexus in the hilar area. The patient recovered well and was discharged on the 19th postoperative day.ConclusionsvEDS can cause arterial rupture after intestinal surgery. Therefore, careful post-operative management is necessary. Moreover, cooperation with interventional radiologists is important for prompt treatment of vascular complications.

Crustal shear wave velocity and radial anisotropy beneath the Mississippi embayment from ambient noise tomography

Imaging of shallow multiple basins and middle to lower crustal structure beneath the Mississippi embayment is still limited. No tomography studies have delineated multiple basins as effectively as those from reflection and drilling experiments. Several studies have constructed different velocity models for the middle to lower crust. We take advantage of the Northern Embayment Lithosphere Experiment dataset and long-term deployment of 277 3-component broadband stations installed from 1990 to 2018 to image crustal shear wave velocity and radial anisotropy in the Mississippi embayment. We first construct 5–40s group velocity maps for Rayleigh wave and 5–30s ones for Love wave. In the 5 s group velocity map, we observe that low velocity features correlate spatially with the sediment thickness from the Crust 1.0 model. High velocity anomalies are associated with the Ozark uplift and the Nashville Dome. In the 32 s group velocity map, high-low velocity boundaries align with 40 km crustal thickness contours from the Crust 1.0 model. We then invert Rayleigh and Love group velocity dispersion for shear wave velocity and radial anisotropy at each grid point and construct a 3D model accordingly. At the depth of 0–5 km of the model, we find that low velocity features characterize the Mississippi Valley Graben, Rough Creek Graben, Black Warrior Basin, and coastal flood plain. High velocity features mark thinly sedimented regions, like the Ozark uplift and the Nashville Dome. Regions with high gravity anomalies are characterized with negative anisotropies. At the depth of 5–12 km, we observe low velocity features in the Missouri Batholith, centering around 10 km. This region is characterized with negative radial anisotropy (Vsh < Vsv), inferring possible intrusions. High-low velocity boundaries correlate with the Appalachian-Ouachita thrust front. At the depth of 12–24 km, the Mississippi Valley Graben is filled with high velocity material, which may be related to the formation of the graben due to isostatic equilibrium. At the depth of 24–43 km, high velocity anomalies characterize the lower crust of the Mississippi embayment, consistent with high density features from the inversion of free air anomaly. The high velocity anomaly might be responsible for the formation of the embayment due to isostatic adjustment. The average velocity in the lower crust is approximately 4.3 km/s. Mafic Pikwitonei granulite is a possible material, indicating relative strong lower crust. This work provides useful information to explain earthquake occurrence in the New Madrid Seismic Zone and regional tectonic settings.

Gastro-Colo-Cutaneous Fistula Occurring After Percutaneous Endoscopic Gastrostomy Procedure

An 82-year-old man diagnosed with supraglottic cancer sought a consultation for percutaneous endoscopic gastrostomy (PEG) placement. Preoperative chest radiography (posterior-anterior [PA] view) revealed no abnormalities, and PEG tube placement was performed using the “pull” method. Chest radiography (PA view) performed 3 days postoperatively showed free air that was not observed immediately after PEG tube placement; therefore, the patient was diagnosed with pneumoperitoneum. Abdominal computed tomography confirmed that the PEG tube was appropriately positioned within the stomach; however, the colon was observed between the abdominal wall and stomach, which indicated that the PEG tube had passed through the colon. Review of preoperative chest radiographs (PA views) confirmed that the colon was visualized in the area wherein usually stomach gas should have been observed. The patient was diagnosed with a gastro-colo-cutaneous fistula that occurred postoperatively, following a procedure that was performed without confirmation of anatomical variations. The PEG tube was removed surgically, and we performed percutaneous gastrostomy.

Electro-thermal performance evaluation of a prismatic battery pack for an electric vehicle

Abstract In recent years, electric vehicles (EVs) have grown in popularity as a viable way to reduce greenhouse gas emissions by replacing conventional vehicles. The need for EV batteries is steadily increasing. An essential and expensive part of electric transportation is the battery. The operating temperature of the lithium-ion (Li-ion) battery significantly impacts the performance of the EV battery pack. Battery packs undergo temperature fluctuations during the charging and discharging procedures due to internal heat generation, necessitating an examination of the temperature distribution of the battery pack. The geometrical spacing between cells is considered larger and identical and is kept open on two sides for free air circulation. A novel battery thermal management system (BTMS) design is required to effectively dissipate heat from the prismatic battery pack module. The electro-thermal behaviour of the prismatic Li-ion battery pack module was investigated based on the high charge/discharge rate. This study presents the development of a three-dimensional free open-source OpenFOAM computational fluid dynamics model for prismatic cell battery packs that simulates heat generation, air flow field, and temperature distribution across the width and depth of the battery pack module. The prismatic battery pack simulation results are compared with the experimental and simulation results of the cylindrical battery pack. It was also revealed that prismatic cells generate more heat on the backside, requiring battery packs to have increased cooling and space between individual cells to ensure sufficient air circulation for cooling and gas removal. The BTMS is improved by designing with increased space among the prismatic battery cells as compared with the conventional prismatic cell battery pack design.

Patient Profile of Primary Peritonitis, Secondary Peritonitis, and Tertiary Peritonitis

Background: Peritonitis is an inflammation that occurs in the peritoneum. The complex structure of the abdomen makes diagnosing and treating intraperitoneal infections challenging in the practice of medicine. Purpose: This study aims to determine the profile of primary peritonitis, secondary peritonitis, and tertiary peritonit patients treated at RSUP Prof. Dr. R. D. Kandou Manado in 2022. Methods: This study used a retrospective descriptive method using medical record data of peritonitis patients during the period January – December 2022. Result : Peritonitis patients are treated at RSUP. Prof. Dr. R. D. Kandou Manado most often occurs in men. Generally occurs in the age group of 19-59 years. Based on the etiology, Hepatic cirrhosis (45%) is the most common etiology of primary peritonitis, gastric perforation (38%) is the  most common etiology of secondary peritonitis, post appendectomy (18%), post nephrostomy (18%) and leakage sigmoid anastomosis (18%) is the most common etiology of tertiary peritonitis. Generally patients have radiological features of preperitoneal fat depletion (44%), and subdiaphragm free air (20%). Most patients receive operative treatment. Most patients present with sepsis. Conclusion: Peritonitis is most common in males, age group 19-59 years, most primary peritonitis is caused by hepatic cirrhosis, most secondary peritonitis is caused by gastric perforation, and most tertiary peritonitis is caused by post appendectomy, post nephrostomy and leakage sigmoid anastomosis. Most patients present with depletion of preperitonela fat, subdiaphragmatic free air, receive operative treatment, and present with sepsis. &#x0D; Keywords: profile; primary peritonitis; secondary peritonitis; tertiary peritonitis.

Water treatment with free-bubbling corrugated sheet MBR

Having previously introduced a new type corrugated-sheet membrane bioreactor (CS-MBR) with slug bubbling, this work investigates its water treatment performance and hydrodynamic optimization under a free bubbling regime. Experiments in parallel were conducted to compare CS-MBR with flat sheet membrane bioreactor (FS-MBR). The transmembrane pressure (TMP) and permeability results indicate that the corrugated sheet membrane has better anti-fouling performance with a final flux after 15 days of operation that was 45 % higher than that of the flat sheet membrane that had been tested in parallel. The analysis results of effluent quality and sludge extracellular polymeric substances (EPS) indicate that the membrane configuration has little impact on the effluent quality and sludge properties in the system. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) revealed the accumulation pattern of foulants on the surface of the corrugated sheet membrane and suggested that the corrugations were the cause of the improved anti-fouling performance. Bis-(3′-5′)-cyclic dimeric guanosine monophosphate (c-di-GMP) was extracted from fouling example at membrane surfaces, which was 50 % lower in the CS-MBR than in the FS-MBR. Computational Fluid Dynamics (CFD) simulations showed that channel gap distance of 2– 4 mm combined with 20 m/s nozzle velocity could produce an intense hydrodynamic effect. Based on the traditional free bubbling air usage, total air consumption of this CS-MBR optimal design is expected to save up to 70 % on energy.

Using Free Air CO2 Enrichment data to constrain land surface model projections of the terrestrial carbon cycle

Abstract. Predicting the responses of terrestrial ecosystem carbon to future global change strongly relies on our ability to model accurately the underlying processes at a global scale. However, terrestrial biosphere models representing the carbon and nitrogen cycles and their interactions remain subject to large uncertainties, partly because of unknown or poorly constrained parameters. Parameter estimation is a powerful tool that can be used to optimise these parameters by confronting the model with observations. In this paper, we identify sensitive model parameters from a recent version of the ORgainzing Carbon and Hydrology in Dynamic Ecosystems (ORCHIDEE) land surface model that includes the nitrogen cycle. These sensitive parameters include ones involved in parameterisations controlling the impact of the nitrogen cycle on the carbon cycle and, in particular, the limitation of photosynthesis due to leaf nitrogen availability. We optimise these ORCHIDEE parameters against carbon flux data collected on sites from the FLUXNET network. However, optimising against present-day observations does not automatically give us confidence in future projections of the model, given that environmental conditions are likely to shift compared to the present day. Manipulation experiments give us a unique look into how the ecosystem may respond to future environmental changes. One such type of manipulation experiment, the Free Air CO2 Enrichment (FACE) experiment, provides a unique opportunity to assess vegetation response to increasing CO2 by providing data under ambient and elevated CO2 conditions. Therefore, to better capture the ecosystem response to increased CO2, we add the data from two FACE sites to our optimisations, in addition to the FLUXNET data. We use data from both CO2 conditions of FACE, which allows us to gain extra confidence in the model simulations using this set of parameters. We find that we are able to improve the magnitude of modelled productivity. Although we are unable to correct the interannual variability fully, we start to simulate possible progressive nitrogen limitation at one of the sites. Using an idealised simulation experiment based on increasing atmospheric CO2 by 1 % yr−1 over 100 years, we find that optimising against only FLUXNET data tends to imply a large fertilisation effect, whereas optimising against FLUXNET and FACE data (with information about nutrient limitation and acclimation of plants) decreases it significantly.

Reassessing acquired neonatal intestinal diseases using unsupervised machine learning.

Acquired neonatal intestinal diseases have an array of overlapping presentations and are often labeled under the dichotomous classification of necrotizing enterocolitis (which is poorly defined) or spontaneous intestinal perforation, hindering more precise diagnosis and research. The objective of this study was to take a fresh look at neonatal intestinal disease classification using unsupervised machine learning. Patients admitted to the University of Florida Shands Neonatal Intensive Care Unit January 2013-September 2019 diagnosed with an intestinal injury, or had imaging findings of portal venous gas, pneumatosis, abdominal free air, or had an abdominal drain placed or exploratory laparotomy during admission were included. Congenital gastroschisis, omphalocele, intestinal atresia, malrotation were excluded. Data was collected via retrospective chart review with subsequent hierarchal, unsupervised clustering analysis. Five clusters of intestinal injury were identified: Cluster 1 deemed the "Low Mortality" cluster, Cluster 2 deemed the "Mature with Inflammation" cluster, Cluster 3 deemed the "Immature with High Mortality" cluster, Cluster 4 deemed the "Late Injury at Full Feeds" cluster, and Cluster 5 deemed the "Late Injury with High Rate of Intestinal Necrosis" cluster. Unsupervised machine learning can be used to cluster acquired neonatal intestinal injuries. Future study with larger multicenter datasets is needed to further refine and classify types of intestinal diseases. Unsupervised machine learning can be used to cluster types of acquired neonatal intestinal injury. Five major clusters of acquired neonatal intestinal injury are described, each with unique features. The clusters herein described deserve future, multicenter study to determine more specific early biomarkers and tailored therapeutic interventions to improve outcomes of often devastating neonatal acquired intestinal injuries.

Degree of Uncertainty in Reporting Imaging Findings for Necrotizing Enterocolitis: A Secondary Analysis from a Pilot Randomized Diagnostic Trial.

Diagnosis of necrotizing enterocolitis (NEC) relies heavily on imaging, but uncertainty in the language used in imaging reports can result in ambiguity, miscommunication, and potential diagnostic errors. To determine the degree of uncertainty in reporting imaging findings for NEC, we conducted a secondary analysis of the data from a previously completed pilot diagnostic randomized controlled trial (2019-2020). The study population comprised sixteen preterm infants with suspected NEC randomized to abdominal radiographs (AXRs) or AXR + bowel ultrasound (BUS). The level of uncertainty was determined using a four-point Likert scale. Overall, we reviewed radiology reports of 113 AXR and 24 BUS from sixteen preterm infants with NEC concern. The BUS reports showed less uncertainty for reporting pneumatosis, portal venous gas, and free air compared to AXR reports (pneumatosis: 1 [1-1.75) vs. 3 [2-3], p < 0.0001; portal venous gas: 1 [1-1] vs. 1 [1-1], p = 0.02; free air: 1 [1-1] vs. 2 [1-3], p < 0.0001). In conclusion, we found that BUS reports have a lower degree of uncertainty in reporting imaging findings of NEC compared to AXR reports. Whether the lower degree of uncertainty of BUS reports positively impacts clinical decision making in infants with possible NEC remains unknown.

Impact of climate change on persistent cold-air pools in an alpine valley during the 21st century

Abstract. When anticyclonic conditions persist over mountainous regions in winter, cold-air pools (i.e. thermal inversions) develop in valleys and persist from a few days to a few weeks. During these persistent cold-air pool (PCAP) episodes the atmosphere inside the valley is stable and vertical mixing is prevented, promoting the accumulation of pollutants close to the valley bottom and worsening air quality. The purpose of this paper is to address the impact of climate change on PCAPs until the end of this century for the alpine Grenoble valleys. The long-term projections produced with the general circulation model MPI (from the Max Planck Institute) downscaled over the Alps with the regional climate model MAR (Modèle Atmosphérique Régional) are used to perform a statistical study of PCAPs over the period 1981–2100. The trends of the main characteristics of PCAPs, namely their intensity, duration, and frequency, are investigated for two future scenarios, SSP2–4.5 and SSP5–8.5. We find that the intensity of PCAPs displays a statistically significant decreasing trend for the SSP5–8.5 scenario only. This decay is explained by the fact that air temperature over the century increases more at 2 m above the valley bottom than in the free air at mid-altitudes in the valley; this might be due to the increase of specific humidity near the ground. The vertical structure of two PCAPs, one in the past and one around 2050, is next investigated in detail. For this purpose, the WRF (Weather Research and Forecasting) model, forced by MAR for the worst-case scenario (SSP5–8.5), is used at a high resolution (111 m). The PCAP episodes are carefully selected from the MAR data so that a meaningful comparison can be performed. The future episode is warmer at all altitudes than the past episode (by at least 4 ∘C) and displays a similar inversion height, which are very likely generic features of future PCAPs. The selected episodes also have similar along-valley wind but different stability, with the future episode being more stable than the past episode. Overall, this study shows that the atmosphere in the Grenoble valleys during PCAP episodes tends to be slightly less stable in the future under the SSP5–8.5 scenario, and statistically unchanged under the SSP2–4.5 scenario, but that very stable PCAPs can still form.

Widespread Pesticide Distribution in the European Atmosphere Questions their Degradability in Air.

Risk assessment of pesticide impacts on remote ecosystems makes use of model-estimated degradation in air. Recent studies suggest these degradation rates to be overestimated, questioning current pesticide regulation. Here, we investigated the concentrations of 76 pesticides in Europe at 29 rural, coastal, mountain, and polar sites during the agricultural application season. Overall, 58 pesticides were observed in the European atmosphere. Low spatial variation of 7 pesticides suggests continental-scale atmospheric dispersal. Based on concentrations in free tropospheric air and at Arctic sites, 22 pesticides were identified to be prone to long-range atmospheric transport, which included 15 substances approved for agricultural use in Europe and 7 banned ones. Comparison between concentrations at remote sites and those found at pesticide source areas suggests long atmospheric lifetimes of atrazine, cyprodinil, spiroxamine, tebuconazole, terbuthylazine, and thiacloprid. In general, our findings suggest that atmospheric transport and persistence of pesticides have been underestimated and that their risk assessment needs to be improved.