Adsorption of Carbon Dioxide on Unsaturated Metal Sites in M2 (dobpdc) Frameworks with Exceptional Structural Stability and Relation between Lewis Acidity and Adsorption Enthalpy.

A series of metal-organic frameworks (MOFs) M2 (dobpdc) (M=Mn, Co, Ni, Zn; H4 dobpdc=4,4'-dihydroxy-1,1'-biphenyl-3,3'-dicarboxylic acid), with a highly dense arrangement of open metal sites along hexagonal channels were prepared by microwave-assisted or simple solvothermal reactions. The activated materials were structurally expanded when guest molecules including CO2 were introduced into the pores. The Lewis acidity of the open metal sites varied in the order MnZn, as confirmed by C=O stretching bands in the IR spectra, which are related to the CO2 adsorption enthalpy. DFT calculations revealed that the high CO2 binding affinity of transition-metal-based M2 (dobpdc) is primarily attributable to the favorable charge transfer from CO2 (oxygen lone pair acting as a Lewis base) to the open metal sites (Lewis acid), while electrostatic effects, the underlying factor responsible for the particular order of binding strength observed across different transition metals, also play a role. The framework stability against water coincides with the order of Lewis acidity. In this series of MOFs, the structural stability of Ni2 (dobpdc) is exceptional; it endured in water vapor, liquid water, and in refluxing water for one month, and the solid remained intact on exposure to solutions of pH 2-13. The DFT calculations also support the experimental finding that Ni2 (dobpdc) has higher chemical stability than the other frameworks.

Percutaneous OxyRVAD in a Patient with Severe Respiratory Failure and Right Heart Failure: A Case Report.

Venovenous extracorporeal membrane oxygenation (VV ECMO) is often used in cases of severe respiratory failure, especially in patients considered for lung transplantation. However, because many lung diseases can ultimately result in right heart failure, the treatment of secondary right heart failure can present a challenge when the patient is already under VV ECMO support. In such cases, an oxygenated-right ventricular assist device (OxyRVAD) can be used. OxyRVAD is designed to maintain anterograde blood flow and prevent right ventricular distension. Moreover, the pulmonary arterial cannula can be inserted percutaneously. We report a case in which percutaneous OxyRVAD was successfully implemented to manage right heart failure in a patient with respiratory failure who was on VV ECMO.

Early thrombus detection in the extracorporeal membrane oxygenation circuit by noninvasive real-time ultrasonic sensors.

Thrombus formation in extracorporeal membrane oxygenation (ECMO) remains a major concern as it can lead to fatal outcomes. To the best of our knowledge, there is no standard non-invasive method for quantitatively measuring thrombi. This study's purpose was to verify thrombus detection in an ECMO circuit using novel, non-invasive ultrasonic sensors in real-time, utilizing the fact that the ultrasonic velocity in a thrombus is known to be higher than that in the blood. Ultrasonic sensors with a customized chamber, an ultrasonic pulse-receiver, and a digital storage oscilloscope (DSO) were used to set up the measuring unit. The customized chamber was connected to an ECMO circuit primed with porcine blood. Thrombi formed from static porcine blood were placed in the circuit and ultrasonic signals were extracted from the oscilloscope at various ECMO flow rates of 1-4 L/min. The ultrasonic signal changes were successfully detected at each flow rate on the DSO. The ultrasonic pulse signal shifted leftward when a thrombus passed between the two ultrasonic sensors and was easily detected on the DSO screen. This novel real-time non-invasive thrombus detection method may enable the early detection of floating thrombi in the ECMO system and early management of ECMO thrombi.

Development of a Risk Scoring Model to Predict Unexpected Conversion to Thoracotomy during Video-Assisted Thoracoscopic Surgery for Lung Cancer.

Background: Unexpected conversion to thoracotomy during planned video-assisted thoracoscopic surgery (VATS) can lead to poor outcomes and comparatively high morbidity. This study was conducted to assess preoperative risk factors associated with unexpected thoracotomy conversion and to develop a risk scoring model for preoperative use, aimed at identifying patients with an elevated risk of conversion. Methods: A retrospective analysis was conducted of 1,506 patients who underwent surgical resection for non-small cell lung cancer. To evaluate the risk factors, univariate analysis and logistic regression were performed. A risk scoring model was established to predict unexpected thoracotomy conversion during VATS of the lung, based on preoperative factors. To validate the model, an additional cohort of 878 patients was analyzed. Results: Among the potentially significant clinical variables, male sex, previous ipsilateral lung surgery, preoperative detection of calcified lymph nodes, and clinical T stage were identified as independent risk factors for unplanned conversion to thoracotomy. A 6-point risk scoring model was developed to predict conversion based on the assessed risk, with patients categorized into 4 groups. The results indicated an area under the receiver operating characteristic curve of 0.747, with a sensitivity of 80.5%, specificity of 56.4%, positive predictive value of 1.8%, and negative predictive value of 91.0%. When applied to the validation cohort, the model exhibited good predictive accuracy. Conclusion: We successfully developed and validated a risk scoring model for preoperative use that can predict the likelihood of unplanned conversion to thoracotomy during VATS of the lung.

Nitrous oxide emission and sweet potato yield in upland soil: Effects of different type and application rate of composted animal manures.

The aims of this study were to determine type and application rate of composted animal manure to optimize sweet potato yield relative to N2O emissions from upland soils. To this end, the study was conducted on upland soils amended with different types and rates of composted animal manure and located at two geographically different regions of South Korea. Field trials were established at Miryang and Yesan in South Korea during the sweet potato (Ipomoea batatas) growing season over 2 years: 2017 (Year 1) and 2018 (Year 2). Three composted animal manures (chicken, cow, and pig) were applied at the rates of 0, 10, and 20 Mg ha-1 to upland soils in both locations. In both Years and locations, manure type did not affected significantly cumulative N2O emissions from soil during the sweet potato growing season or the belowground biomass of sweet potato. However, application rate of animal manures affected significantly the cumulative N2O emission, nitrogen (N) in soil, and belowground biomass of sweet potato. An increase in cumulative N2O emission with application rates of animal manures was related to total N and inorganic N concentration in soil. The belowground biomass yield of sweet potato but also the cumulative N2O emission increased with increasing application rate of composted animal manures up to 7.6 and 16.0 Mg ha-1 in Miryang and Yesan, respectively. To reduce N2O emission from arable soil while increasing crop yield, composted animal manures should be applied at less than application rate that produce the maximum belowground biomass of sweet potato.

Use of cytochrome c oxidase subunit i (COI) nucleotide sequences for identification of the Korean Luciliinae fly species (Diptera: Calliphoridae) in forensic investigations.

Blowflies, especially species belonging to the subfamily Luciliinae, are the first insects to lay eggs on corpses in Korea. Fast and accurate species identification has been a key task for forensic entomologists. Because conventional morphologic identification methods have many limitations with respect to forensic practice, molecular methods have been proposed to identify fly species of forensic importance. To this end, the authors amplified and sequenced the full length of the cytochrome c oxidase subunit I (COI) gene of the Luciliinae fly species collected in Korea. The results showed the COI sequences are instrumental in identifying Luciliinae fly species. However, when compared with previously reported data, considerable inconsistencies were noted. Hemipyrellia ligurriens data in this study differed significantly from two of the five pre-existing data. Two closely related species, Lucilia illustris and Lucilia caesar, showed an overlap of COI haplotypes due to four European sequences. The results suggest that more individuals from various geographic regions and additive nuclear DNA markers should be analyzed, and morphologic identification keys must be reconfirmed to overcome these inconsistencies.

Sequences of the cytochrome C oxidase subunit I (COI) gene are suitable for species identification of Korean Calliphorinae flies of forensic importance (Diptera: Calliphoridae).

Calliphorinae fly species are important indicators of the postmortem interval especially during early spring and late fall in Korea. Although nucleotide sequences of various Calliphorinae fly species are available, there has been no research on the cytochrome c oxidase subunit I (COI) nucleotide sequences of Korean Calliphorinae flies. Here, we report the full-length sequences of the COI gene of four Calliphorinae fly species collected in Korea (five individuals of Calliphora vicina, five Calliphora lata, four Triceratopyga calliphoroides and three Aldrichina grahami). Each COI gene was amplified by polymerase chain reaction and directly sequenced and the resulting nucleotide sequences were aligned and analyzed by MEGA4 software. The results indicate that COI nucleotide sequences can be used to distinguish between these four species. Our phylogenetic result coincides with recent taxonomic views on the subfamily Calliphorinae in that the genera Aldrichina and Triceratopyga are nested within the genus Calliphora.