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Metal-organic frameworks (MOFs), which are highly ordered structures exhibiting sub-nanometer porosity, possess significant potential for diverse gas applications. However, their inherent insulative properties limit their utility in electrochemical gas sensing. This investigation successfully modifies the electrical conductivity of zeolitic imidazolte framework-8 (ZIF-8) employing a straightforward surface oxidation methodology. A ZIF-8 polycrystalline layer is applied on a wafer-scale oxide substrate and subjects to thermal annealing at 300 °C under ambient air conditions, resulting in nanoscale oxide layers while preserving the fundamental properties of the ZIF-8. Subsequent exposure to NO2 instigates the evolution of an electrically interconnected structure with the formation of electron-rich dopants derived from the decomposition of nitrogen-rich organic linkers. The N-carbon-hybridized ZnO/ZIF-8 device demonstrates remarkable sensitivity (≈130 ppm-1 ) and extreme selectivity in NO2 gas detection with a lower detection limit of 0.63 ppb under 150 °C operating temperature, surpassing the performance of existing sensing materials. The exceptional performances result from the Debye length scale dimensionality of ZnO and the high affinity of ZIF-8 to NO2 . The methodology for manipulating MOF conductivity through surface oxidation holds the potential to accelerate the development of MOF-hybridized conductive channels for a variety of electrical applications.
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We consider foraging behaviors in a two-dimensional continuum space and show that a cooperative chasing strategy can emerge in a social dilemma. Predators can use two different chasing strategies: A direct chasing strategy (DCS) and a group chasing strategy (GCS). The DCS is a selfish strategy with which a chaser moves straight toward the nearest prey, and the GCS is a cooperative strategy in the sense that the chaser chooses the chasing direction for the group at a cost of its own speed. A prey flees away from the nearest hazard, either a chaser or the boundary, within its recognition range. We check the capturing activities of each strategy and find a social dilemma between the two strategies because the GCS is more efficient for the group whereas the DCS is better individually. Using a series of numerical simulations, we further show that the cooperative strategy can proliferate when a learning process of nearby successful strategies is introduced.
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BACKGROUND: In patients with severe trauma, the diagnosis of acute kidney injury (AKI) is important because it is a predictive factor for poor prognosis and can affect patient care. The diagnosis and staging of AKI are based on change in serum creatinine (SCr) levels from baseline. However, baseline creatinine levels in patients with traumatic injuries are often unknown, making the diagnosis of AKI in trauma patients difficult. This study aimed to enhance the accuracy of AKI diagnosis in trauma patients by presenting an appropriate reference creatinine estimate (RCE). METHODS: We reviewed adult patients with severe trauma requiring intensive care unit admission between 2015 and 2019 (n=3,228) at a single regional trauma center in South Korea. AKI was diagnosed based on the current guideline published by the Kidney Disease: Improving Global Outcomes organization. AKI was determined using the following RCEs: estimated SCr75-modification of diet in renal disease (MDRD), trauma MDRD (TMDRD), admission creatinine level, and first-day creatinine nadir. We assessed inclusivity, prognostic ability, and incrementality using the different RCEs. RESULTS: The incidence of AKI varied from 15% to 46% according to the RCE used. The receiver operating characteristic curve of TMDRD used to predict mortality and the need for renal replacement therapy (RRT) had the highest value and was statistically significant (0.797, P<0.001; 0.890, P=0.002, respectively). In addition, the use of TMDRD resulted in a mortality prognostic ability and the need for RRT was incremental with AKI stage. CONCLUSIONS: In this study, TMDRD was feasible as a RCE, resulting in optimal post-traumatic AKI diagnosis and prognosis.
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Background and Objectives: As the number of minimally invasive surgeries, including video-assisted thoracoscopic surgery, increases, small, deeply located lung nodules are difficult to visualize or palpate; therefore, localization is important. We studied the use of a mixture of indigo-carmine and lipiodol, coupled with a transbronchial approach-to achieve accurate localization and minimize patient discomfort and complications. Materials and Methods: A total of 60 patients were enrolled from May 2019 to April 2022, and surgery was performed after the bronchoscopy procedure. Wedge resection or segmentectomy was performed, depending on the location and size of the lesion. Results: In 58/60 (96.7%) patients, the localization of the nodules was successful after localization, and 2/60 required c-arm assistance. None of the patients complained of discomfort during the procedure; in all cases, margins were found to be free from carcinoma, as determined by the final pathology results. Conclusions: We recommend this localization technique using mixture of indigo carmine and lipiodol, in concert with the transbronchial approach, because the procedure time is short, patient's discomfort is low, and success rate is high.
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Neoplasias Pulmonares , Nódulo Pulmonar Solitario , Carmín , Aceite Etiodizado , Humanos , Carmin de Índigo/efectos adversos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Nódulo Pulmonar Solitario/inducido químicamente , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/cirugíaRESUMEN
In this study, the effects of CO2 thermochemical agent and a metal oxide catalyst (Co3O4) on thermochemical banner waste conversion were explored. The results revealed that compared to the non-catalytic conversion of banner waste under N2 environment, the conversion under CO2 yielded more non-condensable gases owing to an enhanced thermal cracking of volatiles. In addition, the CO and CH4 yields at >700 °C in CO2 increased considerably owing to the reverse water-gas shift reaction and CO2 methanation. The CO2 agent reduced the yields of condensables (e.g., benzoic acids, phthalic acids, esters, biphenyls, fluorenes) and decomposition residue (e.g., char and wax), which could be attributed to the enhancement of the thermal cracking of volatiles evolved during the banner waste conversion by CO2 and the C-H and O-H bonds present in the feedstock. In addition, the Co3O4 catalyst promoted the decarboxylation reaction under N2 environment, whereas it promoted the methanation and reverse water-gas shift reaction under CO2. This indicates that compared to the non-catalytic CO2-assisted banner waste conversion, the use of CO2 for the conversion of banner waste in the presence of Co3O4 significantly increased the yields of CH4 and CO. Furthermore, Co3O4 promoted the thermal cracking of polyester bond, thus decreasing the yields of long-chain chemical compounds. In addition, the simultaneous use of Co3O4 catalyst and CO2 agent minimized the formation of char and wax. For all cases (N2 versus CO2, non-catalytic versus catalytic), an increase in temperature enhanced the total permanent gas yield and decreased the yields of condensables, char, and wax. The findings of this study revealed the importance of the synergistic use of Co3O4 catalyst and CO2 agent for the plastic waste upcycling, such as banner waste.
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Dióxido de Carbono , Plásticos , Cobalto , Gases , Óxidos , AguaRESUMEN
Herein, the pyrolysis of low-density polyethylene (LDPE) scrap in the presence of a H-ZSM-11 zeolite was conducted as an effort to valorize plastic waste to fuel-range chemicals. The LDPE-derived pyrolytic gas was composed of low-molecular-weight aliphatic hydrocarbons (e.g., methane, ethane, propane, ethylene, and propylene) and hydrogen. An increase in pyrolysis temperature led to increasing the gaseous hydrocarbon yields for the pyrolysis of LDPE. Using the H-ZSM-11 catalyst in the pyrolysis of LDPE greatly enhanced the content of propylene in the pyrolytic gas because of promoted dehydrogenation of propane formed during the pyrolysis. Apart from the light aliphatic hydrocarbons, jet fuel-, diesel-, and motor oil-range hydrocarbons were found in the pyrolytic liquid for the non-catalytic and catalytic pyrolysis. The change in pyrolysis temperature for the catalytic pyrolysis affected the hydrocarbon compositions of the pyrolytic liquid more materially than for the non-catalytic pyrolysis. This study experimentally showed that H-ZSM-11 can be effective at producing fuel-range hydrocarbons from LDPE waste through pyrolysis. The results would contribute to the development of waste valorization process via plastic upcycling.
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In a geographically distributed population, assortative clustering plays an important role in evolution by modifying local environments. To examine its effects in a linear habitat, we consider a one-dimensional grid of cells, where each cell is either empty or occupied by an organism whose replication strategy is genetically inherited to offspring. The strategy determines whether to have offspring in surrounding cells, as a function of the neighborhood configuration. If more than one offspring compete for a cell, then they can be all exterminated due to the cost of conflict depending on environmental conditions. We find that the system is more densely populated in an unfavorable environment than in a favorable one because only the latter has to pay the cost of conflict. This observation agrees reasonably well with a mean-field analysis which takes assortative clustering of strategies into consideration. Our finding suggests a possibility of intrinsic nonlinearity between environmental conditions and population density when an evolutionary process is involved.
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Herein, pyrolysis of cattle manure was conducted to synthesize an effective material for removing heavy metals (e.g., selenium) from water environments. To remove selenate from aqueous solution, iron-impregnated cattle manure biochar (Fe/CM-biochar) was synthesized. The Fe-impregnation was performed by pre-treating cattle manure before its pyrolysis. The pretreatment increased the biochar yield. Influence of various factors such as contacting time, initial selenate concentration, reaction temperature, pH, and presence of coexisting anions were explored by performing batch adsorption experiments. The selenate adsorption reached equilibrium within 15 min. The Langmuir model was better fitted to equilibrium adsorption data than the Freundlich model. The maximum adsorption capacity of Fe/CM-biochar was calculated to be 52.56 mg-Se/g, which is superior to other adsorbents reported in the literature. As the reaction temperature increased in the range (15-35) °C, selenate adsorption on Fe/CM-biochar showed an endothermic and nonspontaneous reaction. The enthalpy change during selenate adsorption was 18.44 kJ/mol, which ranges in physical adsorption. The increase of solution pH (3-11) reduced the selenate adsorption (46.4-37.7 mg-Se/g). The extent of co-existing anion impact on selenate adsorption followed an order of HPO42- > HCO3- > SO42- > NO3-. These results indicate that Fe/CM-biochar is an effective functional material for the removal of selenate from wastewater.
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Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Animales , Bovinos , Carbón Orgánico , Cinética , Estiércol , Ácido Selénico , Contaminantes Químicos del Agua/análisisRESUMEN
Lignin directly derived from lignocellulosic biomass has been named a promising source of platform chemicals for the production of bio-based polymers. This review discusses potentially relevant routes to produce renewable aromatic aldehydes (e.g., syringaldehyde and vanillin) from lignin feedstocks (pre-isolated lignin or lignocellulose) that are used to synthesize a range of bio-based polymers. To do this, the processes to make aromatic aldehydes from lignin with their highest available yields are first presented. After that, the routes from such aldehydes to different polymers are explored. Challenges and perspectives of the production the lignin-derived renewable chemicals and polymers are also highlighted.
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In this study, the co-pyrolysis of food waste with lignocellulosic biomass (wood bark) in a continuous-flow pyrolysis reactor was considered as an effective strategy for the clean disposal and value-added utilization of the biowaste. To achieve this aim, the effects of major co-pyrolysis parameters such as pyrolysis temperature, the flow rate of the pyrolysis medium (nitrogen (N2) gas), and the blending ratio of food waste/wood bark on the yields, compositions, and properties of three-phase pyrolytic products (i.e., non-condensable gases, condensable compounds, and char) were investigated. The temperature and the food waste/wood bark ratio were found to affect the pyrolytic product yields, while the N2 flow rate did not. More non-condensable gases and less char were produced at higher temperatures. For example, as the temperature was increased from 300 °C to 700 °C, the yield of non-condensable gases increased from 6.3 to 17.5 wt%, while the yield of char decreased from 63.6 to 30.6 wt% for the co-pyrolysis of food waste and wood bark at a weight ratio of 1:1. Both the highest yield of hydrogen (H2) gas and the most significant suppression of the formation of phenolic and polycyclic aromatic hydrocarbon (PAH) compounds were achieved with a combination of food waste and wood bark at a weight ratio of 1:1 at 700 °C. The results suggest that the synergetic effect of food waste and lignocellulosic biomass during co-pyrolysis can be exploited to increase the H2 yield while limiting the formation of phenolic compounds and PAH derivatives. This study has also proven the effectiveness of co-pyrolysis as a process for the valorization of biowaste that is produced by agriculture, forestry, and the food industry, while reducing the formation of harmful chemicals.
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Contaminantes Ambientales , Eliminación de Residuos , Biomasa , Alimentos , Calor , Hidrógeno , Corteza de la Planta , Pirólisis , MaderaRESUMEN
In this work, we used pyrolysis to treat teabag waste (TBW). Changes in the pyrolysis temperature affected the composition and yield of the products. For example, more non-condensable gases and less char were produced with an increase in the pyrolysis temperature. Pyrolysis conducted under a nitrogen environment yielded caprolactam at temperatures between 400 and 700 °C. An increase in the pyrolysis temperature from 400 to 500 °C increased the caprolactam yield from 3.1 to 6.2 wt.%. At 700 °C, the yield decreased to 4.6 wt.%. The highest caprolactam yield (i.e., 6.2 wt.% at 500 °C) was equivalent to 59.2 wt.% on the basis of the weight of the non-biomass part of the TBW. The pyrolytic products other than caprolactam (e.g., combustible gases, pyrolytic liquid, and char) can function as fuels to supply energy during pyrolysis in order to increase and maintain the temperature. The higher heating values (HHVs) of the combustible gases and pyrolytic liquid produced at 500 °C were 7.7 and 8.3 MJ kg-1, respectively. The HHV of the char produced at 500 °C was 23 MJ kg-1, which is comparable to the HHV of coal. This work will help to develop effective pyrolysis processes to valorize everyday waste by recovering value-added chemicals such as polymer monomers and by producing alternative fuels.
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[Purpose] This study aimed to investigate the effects of McKenzie exercise, Kinesio taping, and myofascial release (MFR) on forward head posture (FHP). [Participants and Methods] Twenty-eight individuals with an FHP were enrolled. participants were randomly assigned to one of three groups: Group A, Group B and Group C. Group A underwent McKenzie exercise and MFR. Group B underwent McKenzie exercise and Kinesio taping. Group C underwent McKenzie exercise, MFR, and Kinesio taping. Interventions for all three groups were provided three times per week for four weeks. The acromion and tragus of ear (A-T length), craniovertebral angle (CVA), Cranial rotation angle (CRA), and neck disability index (NDI) were measured. [Results] The A-T length significantly differed after intervention in all three groups. CVA only significantly differed after intervention in group C. All three groups showed an increase in CRA after intervention; however, these increases were not statistically significant. [Conclusion] Considering these results, these three types of exercise may be recommended as effective exercises to improve posture in adults with FHP.
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Temozolomide (TMZ) is an alkylating agent used for the treatment of glioblastoma. The late autophagy inhibitor chloroquine (CQ) inhibits glioblastoma tumors in a p53-independent and p53-dependent manner. We addressed a possible beneficial effect of combination treatment with TMZ and CQ by examining the molecular and cellular mechanism of co-treatment. Combination treatment of U87 cell (wild type p53) with TMZ and CQ synergistically reduced cell proliferation and enhanced apoptosis, with increased sub-G1 hypodiploid cells and caspase activation. This effect was abolished by a pan-caspase inhibitor, Z-VAD-FMK. TMZ induced autophagy, and the addition of CQ further increased autophagic vacuoles. Inhibition of early stages of autophagy by Beclin 1 knockdown and 3-methyladenine pretreatment prevented the enhanced effect of the combination treatment. The combination treatment also upregulated p53 and phospho-p53 levels, whereas p53 knockdown or overexpression of mutant p53 abolished the combination effect. In contrast, combination therapy had no enhanced effect on U373 cell (mutant p53) proliferation and apoptosis within 3 d, although TMZ induced autophagy and co-treatment with CQ increased autophagic vacuole accumulation. However, long term combination treatment for 9-10 d effectively decreased clonal and cellular growth with increased G2-M arrest. This effect was also abolished by Beclin 1 knockdown. Our data support the beneficial effect of combination treatment with TMZ and CQ in glioma via differential autophagy-associated mechanisms, depending on p53 status.