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According to numerous chamber and free-air CO2 enrichment (FACE) studies with artificially raised CO2 concentration and/or temperature, it appears that increasing atmospheric CO2 concentrations ([CO2]) stimulates crop yield. However, there is still controversy about the extent of the yield stimulation by elevating [CO2] and concern regarding the potential adverse effects when temperature rises concomitantly. Here, we tested the effects of natural elevated [CO2] (ca. 120 ppm above the ambient level in 100 years ago) and warming (ca. 1.7–3.2 °C above the ambient level 100 years ago) on rice growth and yield over three crop seasons via a past reference investigation and current experiment (PRICE) study. In 2020–2022, the rice cultivar Tamanishiki (Oryza sativa, ssp. japonica) was grown in Wagner's pots (1/2000 a) at the experiment fields of Chonnam National University (35°10′ N, 126°53′ E), Gwangju, Korea, according to the pot trial methodology of the reference experiment conducted in 1920–1922. Elevated [CO2] and temperature over the last 100 years significantly stimulated plant height (13.4% on average), tiller number (11.5%), and shoot biomass (10.8%). In addition, elevated [CO2] and warming resulted in a marked acceleration of flowering phenology (6.8% or 5.1 days), potentially leading to adverse effects on tiller number and grain yield. While the harvest index exhibited a dramatic reduction (12.2%), grain yield remained unchanged with elevated [CO2] and warming over the last century. The response of these crop parameters to elevated [CO2] and warming was highly sensitive to sunshine duration during the period from transplanting to heading. Despite the pot-based observations, considering a piecewise response pattern of C3 crop productivity to [CO2] of <500 ppm, our observations demonstrate realistic responses of rice crops to elevated [CO2] (+120 ppm) and moderate warming (+1.7–3.2 °C) in the absence of adaptation measures (e.g., cultivars and agronomic management practices). Hence, our results suggest that the PRICE platform may provide a promising way to better understand and forecast the net impact of climate change on major crops that have historical and experimental archived data, like rice, wheat, and soybean. [ABSTRACT FROM AUTHOR]

This review analyzes the data on co-variations in δ13C and δ15N of soils with land-use types, management, and disturbance obtained from literature to explore potential implications of the dual isotopes in the study of soil organic matter (SOM) sources and C and N processes. Overall, croplands (δ13C and δ15N were − 20.3 ± 4.4‰ and + 7.6 ± 4.4‰, respectively) had greater isotopic values than grasslands (‒26.3 ± 3.0‰ and + 5.4 ± 1.1‰, respectively) and forests (− 26.0 ± 1.1‰ and + 4.3 ± 2.2‰, respectively). For intensively managed lands such as croplands and grasslands, application of organic inputs such as manure and compost of which isotopic signatures differed from the indigenous SOM was the main driver of co-variations in the δ13C and δ15N of SOM. For natural forests, both δ13C and δ15N of SOM co-increased with soil depth, reflecting heavy isotope enrichment during microbial stabilization of SOM and the potential influence of 13C-depleted atmospheric CO2 and 15N-depleted N deposition on the upper soils. Such vertical co-enrichments of 13C and 15N were disturbed by a land-use conversion to other lands including croplands. Though there were indications that land management practices such as tillage in croplands and grazing in grasslands, land-use changes, and land disturbance including forest fire might also affect both δ13C and δ15N, more data need to be accumulated to find a general trend of the isotopic variations of SOM. Analysis of both δ13C and δ15N may enlarge understanding of changes in SOM sources and soil C and N cycling by land-use types, management, change, and disturbance. [ABSTRACT FROM AUTHOR]

Rice residue including root and straw are unique carbon (C) source in paddy soils. However, the potential changes in quantity and chemical composition of rice residue under co-elevated atmospheric CO2 concentration ([CO2]) and air temperature (Tair) and the legacy effect of the changed chemical composition on residue decomposition have not been investigated. This study was conducted to investigate biomass, chemical composition, and decomposability of rice root and straw produced under elevated [CO2] and Tair. Root and straw biomass increased by elevated [CO2] and elevated Tair, respectively, and the greatest biomass was achieved under co-elevated [CO2]-Tair for both root and straw. The concentration of lignin (recalcitrant) decreased while that of nonstructural carbohydrates (less recalcitrant) increased by co-elevated [CO2]-Tair. The ratio of lignin-to-nitrogen (lignin/N) decreased by co-elevated [CO2]-Tair compared to ambient [CO2]-Tair due to increased N and decreased lignin concentrations. Decomposability of root (lignin/N, 36.4) produced under co-elevated [CO2]-Tair was greater than that under ambient co-elevated [CO2]-Tair (lignin/N, 53.7); however, there was no difference in decomposability for straw, which had relatively narrow range of lignin/N (27.3–36.5) regardless of [CO2]-Tair conditions. The results of this study provide a novel insight into the changes in quantity and quality of rice residue under elevated [CO2]-Tair that are necessary to predict changes in paddy soil C sequestration under global warming. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO2 concentration ([CO2]) may change litter chemistry which affects litter decomposability. This study investigated respiration and microbial biomass of soils amended with litter of Pinus densiflora (a coniferous species; pine) and Quercus variabilis (a deciduous species; oak) that were grown under different atmospheric [CO2] and thus had different chemistry. Elevated [CO2] increased lignin/N through increased lignin concentration and decreased N concentration. The CO2 emission from the soils amended with litter produced under the same [CO2] regime was greater for oak than pine litter, confirming that broadleaf litter with lower lignin decomposes faster than needle leaf litter. Within each species, however, soils amended with high lignin/N litter grown under elevated [CO2] emitted more CO2 than those with low lignin/N litter grown under ambient [CO2]. Such contrasting effects of lignin/N on inter- and intra-species variations in litter decomposition should be ascribed to the effects of other litter chemistry variables including nonstructural carbohydrate, calcium and manganese as well as inhibitory effect of N on lignin decomposition. The microbial biomass was also higher in the soils amended with high lignin/N litter than those with low lignin/N litter probably due to low substrate use efficiency of lignin by microbes. Our study suggests that elevated [CO2] increases lignin/N for both species, but increased lignin/N does not always reduce soil respiration and microbial biomass. Further study investigating a variety of tree species is required for more comprehensive understanding of inter- and intra-species variations of litter decomposition under elevated [CO2]. [ABSTRACT FROM AUTHOR]

Potential impacts of climate change on grain sorghum ( Sorghum bicolor) productivity were investigated using the CERES-sorghum model in the Decision Support System for Agrotechnology Transfer v4.5. The model was first calibrated for a sorghum cultivar grown in a free air CO2 enrichment experiment at the University of Arizona, Maricopa, Arizona, USA in 1998. The model was then validated with an independent dataset collected in 1999. The simulated grain yield, growth, and soil water of sorghum for the both years were in statistical agreement with the corresponding measurements, respectively. Neither simulated nor measured yields responded to elevated CO2, but both were sensitive to water supply. The validated model was then applied to simulate possible effects of climate change on sorghum grain yield and water use efficiency in western North America for the years 2080-2100. The projected CO2 fertilizer effect on grain yield was dominated by the adverse effect of projected temperature increases. Therefore, temperature appears to be a dominant driver of the global climate change influencing future sorghum productivity. These results suggest that an increase in water demand for sorghum production should be anticipated in a future high-CO2 world. [ABSTRACT FROM AUTHOR]

Nitrogen isotope abundance ( δN) of paddy rice ( Oryza sativa L.) grown for 110 days after transplanting (DAT) under field conditions with ammonium sulfate (AS with −0.4‰ as a synthetic fertilizer), pig manure compost (PMC with 15.3‰ as a livestock manure compost), and hairy vetch (HV with −0.5‰ as a green manure) was investigated to test the possible use of δN technique in discriminating organically grown from conventionally grown rice. At 15 DAT, the δN of whole rice decreased ( P < 0.05) in the order of 10.5‰ for PMC > 5.5‰ for control (without N input) > 4.0‰ for HV > 1.8‰ for AS. This difference seemed to reflect primarily the δN signal of N sources. Although differences in δN of rice grown with isotopically distinct N inputs (i.e. PMC vs. AS and PMC vs. HV) became smaller over time, the difference (2.8 and 3.0‰ difference at harvest on 110 DAT, respectively) was still significant ( P < 0.05). However, there was no distinguishable difference between AS and HV treatment after 42 DAT. Such effect of N inputs on δN of whole rice was also observed for root, shoot, and grain at harvest. Therefore, our study suggests that it is possible to distinguish rice grown with manure composts from that grown with synthetic fertilizers. However, if green manure of preceding N-fixing plants is used as the N source, δN of rice may not be a good surrogate of N sources. [ABSTRACT FROM AUTHOR]

An experiment was conducted in an Andosol paddy field in Shizukuishi (Iwate Prefecture, Japan) to determine the effects of free-air CO2 enrichment (FACE) on biological N2-fixation activity and soil microbial biomass C at three levels of N application. Rice ( Oryza sativa L. cv. Akitakomachi) plants were grown under ambient CO2 or FACE (ambient +200 µmol mol–1 CO2) conditions throughout the growing season with each treatment having four replicated plots. Three levels of N fertilizer (high, standard and low; 15, 9 and 4 g N m–2, respectively) were applied to examine the effect of different N availability under both CO2 conditions. Soil samples were collected at four different times from upper and lower soil layers (0–1-cm and 1–10-cm soil depths, respectively) and analysed for biological N2-fixation (BNF) activity and microbial biomass C (MBC) by the acetylene reduction and chloroform fumigation-extraction methods, respectively. The amounts of chlorophyll-type compounds (Chls), an index of algal growth, and soil available C were also determined. Compared to the ambient CO2 treatment, the FACE treatment had significantly higher BNF activity in both the upper and lower soil layers at ripening only in low-N soil and at harvest at all three levels of N fertilization rates. MBC was significantly increased by FACE in both the upper and lower soil layers from the middle to later period of the growing season compared to the ambient CO2 treatment. The FACE treatment increased the Chls in the upper soil layers at ripening only in low-N soil and at harvest at all three levels of N fertilization rates. The amount of soil available C was not significantly different between FACE and ambient CO2 treatments in both the upper and lower soil layers throughout the cropping season. From these results it can be concluded that the FACE treatment had a significantly positive influence on BNF activity, MBC and Chls at different levels of N fertilization rates in paddy field during the cropping season. [ABSTRACT FROM AUTHOR]

Venoarterial extracorporeal membrane oxygenation (VA ECMO) is widely used in patients with cardiogenic shock. Insufficient decompression of the left ventricle (LV) is considered a major factor preventing adequate LV recovery. A 40-year-old male was diagnosed with acute myocardial infarction, and revascularization was performed using percutaneous stenting. However, cardiogenic shock occurred, and VA ECMO was initiated. Severe LV failure developed, and percutaneous transaortic catheter venting (TACV) was incorporated into the venous circuit of VA ECMO under transthoracic echocardiography guidance. The patient was successfully weaned from VA ECMO. Percutaneous TACV is an effective, relatively noninvasive, and rapid method of LV decompression in patients undergoing VA ECMO.

A 79-year-old man was admitted to Samsung Changwon Hospital due to chest pain and dyspnea. The ejection fraction was 31% and mean pressure gradient between the left ventricle and aorta was 69.4 mmHg on echocardiography. Chest computed tomography showed severe calcification of the ascending aorta. Aortic valve replacement was successfully performed using a thoracic endovascular aortic repair balloon catheter without classic aortic cross clamping. The patient was discharged on the eleventh postoperative day.

Background: Traumatic rupture of the diaphragm is an unusual type of trauma. In addition, it is difficult to diagnose because it can be accompanied by injuries to other organs. If it is not detected early, the mortality rate can increase due to serious complications. Diaphragmatic rupture is an important indicator of the severity of the trauma. The aim of this study was to investigate the factors affecting the incidence of complications and mortality in patients who had surgery to treat traumatic rupture of the diaphragm., Materials and Methods: The subjects were patients who had undergone a diaphragmatic rupture by blunt trauma or stab wounds except patients who were transferred to other hospitals within 3 days of hospitalization, from January 2000 to December 2007. This study was a retrospective study. 43 patients were hospitalized, and 40 patients were included during the study period. Among them, 28 were male, 12 were female, and the average age was 42 (from 18 to 80). Outcome predictive factors including hypoxia, ventilator application days, revised trauma score (RTS), injury severity score (ISS), age, herniated organs, complications, and the mortality rate were investigated., Results: Causes of trauma included motor vehicle crashes for 20 patients (50%), falls for 10 (25%), stab wounds for 8 (20%), and agricultural machinery accidents for 2 (5%). Most of the patients (36 patients; 90%) had wound sites on the left. Diagnosis was performed within 12 hours for most patients. The diaphragmatic rupture was diagnosed preoperatively in 27 patients (70%) and in 12 patients (30%) during other surgeries. For surgical treatment, thoracotomy was performed in 14 patients (35%), laparotomy in 11 (27.5%), and a surgery combining thoracotomy and laparotomy in 15 patients (37.5%). Herniated organs in the thoracic cavity included the stomach for 23 patients (57.5%), the omentum for 15 patients (37.5%), the colon for 10 patients (25%), and the spleen for 6 patients (15%). Accompanying surgeries included splenectomy for 13 patients (32.5%), lung suture for 6 patients (15%), and liver suture for 5 patients (12.5%). The average hospital stay was 47.80±56.72 days, and the period of ventilation was 3.90±5.8 days. The average ISS was 35.90±16.81 (11~75), and the average RTS was 6.46±1.88 (1.02~7.84). The mortality rate was 17.5% (7 patients). Factors affecting complications were stomach hernia and age. Factors affecting the mortality rate were ISS and RTS., Conclusion: There are no typical symptoms of the traumatic rupture of the diaphragm by blunt trauma. Nor are there any special methods of diagnosis; in fact, it is difficult to diagnose because it accompanies injuries to other organs. Stab wounds are also not easy to diagnose, though they are relatively easy to diagnose compared to blunt trauma because the accompanying injuries are more limited. Suture of the diaphragm can be performed through the chest, the abdomen, or the thoracoabdomen. These surgical methods are chosen based on accompanying organ injuries. When there are many organ injuries, there are a great number of complications. Significant factors affecting the complication rate were stomach hernia and age. ISS and RTS were significant as factors affecting the mortality rate. In the case of severe trauma such as pelvic fractures, frequent physical examinations and chest X-rays are necessary to confirm traumatic rupture of the diaphragm because it does not have specific symptoms, and there are no clear diagnosis methods. Complications and the mortality rate should be reduced with early diagnosis and with treatment by confirming diaphragmatic rupture in the thoracic cavity and the abdomen during surgery.