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Sodium-ion batteries (SIBs) have emerged as a compelling alternative to lithium-ion batteries (LIBs), exhibiting comparable electrochemical performance while capitalizing on the abundant availability of sodium resources. In SIBs, P2/O3 biphasic cathodes, despite their high energy, require furthur improvements in stability to meet current energy demands. This study introduces a systematic methodology that leverages the meta-heuristically assisted NSGA-II algorithm to optimize multi-element doping in electrode materials, aiming to transcend conventional trial-and-error methods and enhance cathode capacity by the synergistic integration of P2 and O3 phases. A comprehensive phase analysis of the meta-heuristically designed cathode material Na0.76Ni0.20Mn0.42Fe0.30Mg0.04Ti0.015Zr0.025O2 (D-NFMO) is presented, showcasing its remarkable initial reversible capacity of 175.5 mAh g-1 and exceptional long-term cyclic stability in sodium cells. The investigation of structural composition and the stabilizing mechanisms is performed through the integration of multiple characterization techniques. Remarkably, the irreversible phase transition of P2âOP4 in D-NFMO is observed to be dramatically suppressed, leading to a substantial enhancement in cycling stability. The comparison with the pristine cathode (P-NFMO) offers profound insights into the long-term electrochemical stability of D-NFMO, highlighting its potential as a high-voltage cathode material utilizing abundant earth elements in SIBs. This study opens up new possibilities for future advancements in sodium-ion battery technology.
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A rational design of heterojunctions with high-quality contacts is essential for efficiently separating photogenerated charge carries and boosting the solar-driven harvesting capability. Herein, we fabricated a novel heterojunction of SnO2 quantum dots-anchored CdS-CdCO3 with g-C3N4 nanosheets as a superior photocatalyst. SnO2 quantum dots (SQDs) with positively charged surfaces were tightly anchored on the negatively charged surface of CdS nanosheets (NSs). The resulting CdS@SnO2 was finally decorated with g-C3N4 NSs, and a new crystalline phase of CdS-CdCO3 was formed during the hydrothermal decoration process, g-C3N4 decorated CdS-CdCO3@SnO2 (CdS-CdCO3@SnO2@g-C3N4). The as-synthesized photocatalysts were evaluated for the degradation of methyl orange dye under solar light conditions. The CdS-CdCO3@SnO2@g-C3N4 exhibited 7.7-fold and 2.3-fold enhancements in photocatalytic activities in comparison to those of the bare CdS and CdS@SnO2 NSs, respectively. The optimal performance of CdS-CdCO3@SnO2@g-C3N4 is primarily attributed to the cascade-type conduction band alignments between 2D/0D/2D heterojunctions, which can harvest maximum solar light and effectively separate photoexcited charge carriers. This work provides a new inspiration for the rational design of 2D/0D/2D heterojunction photocatalyst for green energy generation and environmental remediation applications.
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Compostos de Cádmio , Nanocompostos , Pontos Quânticos , Compostos de Estanho , Pontos Quânticos/química , Compostos de Cádmio/química , Compostos de Estanho/química , Nanocompostos/química , Catálise , Sulfetos/química , Luz Solar , Processos Fotoquímicos , Grafite/química , Compostos Azo/química , Nitrilas/química , Compostos de Nitrogênio/químicaRESUMO
A tandem (two-step) particle swarm optimization (PSO) algorithm is implemented in the argyrodite-based multidimensional composition space for the discovery of an optimal argyrodite composition, i.e., with the highest ionic conductivity (7.78 mS cm-1 ). To enhance the industrial adaptability, an elaborate pellet preparation procedure is not used. The optimal composition (Li5.5 PS4.5 Cl0.89 Br0.61 ) is fine-tuned to enhance its practical viability by incorporating oxygen in a stepwise manner. The final composition (Li5.5 PS4.23 O0.27 Cl0.89 Br0.61 ), which exhibits an ionic conductivity (σion ) of 6.70 mS cm-1 and an activation barrier of 0.27 eV, is further characterized by analyzing both its moisture and electrochemical stability. Relative to the other compositions, the exposure of Li5.5 PS4.23 O0.27 Cl0.89 Br0.61 to a humid atmosphere results in the least amount of H2 S released and a negligible change in structure. The improvement in the interfacial stability between the Li(Ni0.9 Co0.05 Mn0.05 )O2 cathode and Li5.5 PS4.23 O0.27 Cl0.89 Br0.61 also results in greater specific capacity during fast charge/discharge. The structural and chemical features of Li5.5 PS4.5 Cl0.89 Br0.61 and Li5.5 PS4.23 O0.27 Cl0.89 Br0.61 argyrodites are characterized using synchrotron X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. This work presents a novel argyrodite composition with favorably balanced properties while providing broad insights into material discovery methodologies with applications for battery development.
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Bacterial infection and infection-induced immune response have been a life-threatening risk for patients having orthopedic implant surgeries. Conventional biomaterials are vulnerable to biocontamination, which causes bacterial invasion in wounded areas, leading to postoperative infection. Therefore, development of anti-infection and immune-evasive coating for orthopedic implants is urgently needed. Here, we developed an advanced surface modification technique for orthopedic implants termed lubricated orthopedic implant surface (LOIS), which was inspired by slippery surface of Nepenthes pitcher plant. LOIS presents a long-lasting, extreme liquid repellency against diverse liquids and biosubstances including cells, proteins, calcium, and bacteria. In addition, we confirmed mechanical durability against scratches and fixation force by simulating inevitable damages during surgical procedure ex vivo. The antibiofouling and anti-infection capability of LOIS were thoroughly investigated using an osteomyelitis femoral fracture model of rabbits. We envision that the LOIS with antibiofouling properties and mechanical durability is a step forward in infection-free orthopedic surgeries.
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INTRODUCTION: Despite recent advances in neonatal intensive care in Korea, few studies exist on the end-of-life decisions in newborns. In this study, we sought to examine the status of end-of-life decisions in neonates, changes over time, and affecting factors. METHODS: This is a retrospective study of neonates who died between 2001 and 2015 in the neonatal intensive care unit of Dong-A University Hospital in Busan. The types of end-of-life decisions were divided into active resuscitation, withholding treatment, and withdrawing treatment. The study period was divided into 3 time frames using 5-year intervals to investigate changes over time. To identify the associated factors, we analyzed the demographic and clinical characteristics of the neonates and their parents using the χ2 test and independent t test. RESULTS: Of the neonatal deaths included in the analysis (n = 222), active resuscitation, withholding treatment, and withdrawing treatment groups accounted for 73.4%, 25.2%, and 1.4% of cases, respectively. When comparing changes over time, between period 1 (2001-2005), 2 (2006-2010), and 3 (2011-2015), the proportion of active resuscitation decreased significantly, from 80.9% to 60.8%, while that of nonactive resuscitation increased significantly from 19.1% to 39.2%. The factors associated with end-of-life decisions were the clinical condition of the neonate at the time of death, rather than general characteristics or socioeconomic factors. CONCLUSIONS: In Korea, changes in the decisions on end-of-life care in neonates are shifting from active resuscitation to nonactive resuscitation based on clinical conditions.
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Tomada de Decisões , Terapia Intensiva Neonatal/métodos , Ordens quanto à Conduta (Ética Médica) , Assistência Terminal/métodos , Suspensão de Tratamento/estatística & dados numéricos , Causas de Morte , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , República da Coreia , Estudos RetrospectivosRESUMO
A 6-week feeding trial was carried out to evaluate the effects of dietary vitamin E (dl-α-tocopheryl acetate, TA) on growth and mercury (Hg) accumulation in juvenile olive flounder (Paralichthys olivaceus) treated with mercuric chloride (HgCl2). Vitamin E and HgCl2 were added to the semi-purified basal diet. Six semi-purified diets in a 2 × 3 factorial design were formulated to contain 2 levels of Hg (0 or 20 mg HgCl2/kg diet) and 3 levels of vitamin E (0, 100, or 200 mg TA/kg diet). Experimental fish (n = 360, 9.99 ± 0.15 g) were randomly allocated into 30-L tanks at a density of 20 fish per tank with 3 replicates in each treatment and were fed twice a day. At the end of the feeding trial, dietary Hg depressed the growth performances in terms of weight gain (WG), specific growth rate (SGR), feed efficiency (FE) and protein efficiency ratio (PER) in fish, while fish fed the diets supplemented with vitamin E showed significant growth improvement in both presence and absence of HgCl2 in the diets (P < 0.05). Survival rate was not affected in fish fed the experimental diets. Whole body compositions of fish such as lipid and moisture contents were influenced by dietary vitamin E supplementation. Total Hg contents of muscle, liver and kidney tissues were significantly reduced in fish fed diets supplemented with vitamin E (P < 0.05), while the two-way ANOVA showed that increasing Hg concentration has resulted in a reduction in vitamin E. Whole body fatty acids of fish like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) contents were decreased by dietary Hg. However, supplementation of dietary vitamin E improved the α-linolenic acid (ALA) and EPA contents in fish. Our results suggest that dietary supplementation of vitamin E has potential effects on growth improvement and ameliorating inorganic Hg bioaccumulation in juvenile olive flounder.
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A series of calcium phosphates synthesized through a wet precipitation route of hydroxylapatite (HAP) was investigated over a wide range of temperature and pH (25-80 degrees C, and pH 6.5-10.0) using a combination of microscopic and spectroscopic analyses. XRD and FTIR show that monetite and brushite are formed as a single phase at non-ideal conditions of HAP, respectively. From TGA results, it is found that brushite is converted to monetite at a range 175-200 degrees C when heated at the heating rate, 10 degrees C/min. This phase transformation is also observed when brushite is aged at pH 8.5 and 60 degrees C for 24 hr in solution. Morphology of brushite is sensitive to pH variation. At pH 6.5, tabular and platy crystals of brushite are observed whereas needle-like ones are predominant at pH 8.5. For HAP formed at pH 10.0, their shapes tend toward needle-like particles as temperature increases. HAP particles at pH 8.5 are very similar in morphology to HAP at pH 10.0, but their lengths are two or three times as great as those at pH 10.0. These observations demonstrate that desired phase and properties of calcium phosphates can be controlled by pH, temperature, and aging time through a wet precipitation method.
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Coronoid process hyperplasia is a rare condition that causes mouth opening limitation, otherwise known as trismus. The elongated coronoid processes impinge on the medial surfaces of the zygomatic arches when opening the mouth, which limits movement of the mandible and leads to trismus. Patients with trismus due to coronoid process hyperplasia do not have any definite symptoms such as temporomandibular joint pain or sounds upon clinical examination, and no significant abnormal signs are observed on panoramic radiographs or magnetic resonance images of the temporomandibular joint. Thus, the diagnosis of trismus is usually very difficult. However, computed tomography can help with the diagnosis, and the condition can be treated by surgery and postoperative physical therapy. This paper describes four cases of patients who visited our clinic for trismus and were subsequently diagnosed with coronoid process hyperplasia. Three were successfully treated with a coronoidectomy and postoperative physical therapy.
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OBJECTIVES: The purpose of this retrospective study is to find the differentiating characteristics of cystic and cystic-appearing lesions that involve the impacted mandibular third molar by analyzing panoramic radiographs and computed tomography images, and to aid the preoperative diagnosis. MATERIALS AND METHODS: Eighty-one patients who had a mandibular cystic or cystic-appearing lesion that involved impacted mandibular third molar and underwent cyst enucleation were included in the study. The preoperative panoramic radiograph and computed tomography findings were analyzed in accordance to the histopathologic type. RESULTS: Most of the cystic lesions containing the mandibular third molar were diagnosed as a dentigerous cyst (77.8%). The occurrence of mesio-distal displacement of the third molar was more frequent in the odontogenic keratocyst (71.4%) and in the ameloblastoma (85.7%) than in the dentigerous cyst (19.1%). Downward displacement was primarily observed in each group. Odontogenic keratocyst and ameloblastoma showed more aggressive growth pattern with higher rate of bony discontinuity and cortical bone expansion than in dentigerous cyst. CONCLUSION: When evaluating mandibular cystic lesions involving the impacted mandibular third molar, dentigerous cyst should first be suspected. However, when the third molar displacement and cortical bone absorption are observed, then odontogenic keratocyst or ameloblastoma should be considered.
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PURPOSE: The purpose of this study was to use various radiation-permeable and radiation-impermeable materials, used to facilitate the observation of a lesion during a rectal computed tomography (CT) scan, in order to determine the best material to use. MATERIALS AND METHODS: In regard to the study method, the radiation-permeable and radiation-impermeable materials of physiological saline, methylcellulose, contrast medium, ultrasound gel, and air were used to perform scanning with scan parameters that were used in general abdominal scanning. The GSI mode was used for material analysis. RESULTS: According to the results of the phantom study, the average CT value was 25.5 ± 5.9 HU for physiological saline, 77.6 ± 7.3 HU for methylcellulose, 3,070 ± 0.1 HU for contrast medium, 74.1 ± 11.9 HU for ultrasound gel, and -954.1 ± 10.3 HU for air. According to the analysis of materials by energy, contrast medium and physiological saline showed a dramatic decrease in the CT value as energy increased. Methylcellulose showed a gradual decrease in CT value, whereas air showed a small change in CT value according to the graph. CONCLUSIONS: Out of these materials, methylcellulose had the advantage of reducing discomfort in patients, and was more convenient for examiners before and after the rectal CT scan.