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A supersaturated spinel solid solution having a nominal compositional ratio of Mg/Al/Fe = 0.5:1.0:1.5 was prepared using a conventional solid-state reaction at 1573 K in air followed by quenching in ice water. The formula of the resulting spinel structure compound (the spinel) was determined to be (Mg0.50AlFe0.262+Fe1.243+)0.97O4 based on a Rietveld refinement and thermogravimetry, indicating a cation-deficient spinel structure having mixed valences of Fe. This spinel was found to decompose to γ-Fe2O3 and a modified, Fe-poor spinel structure compound via a spinodal decomposition below 855 K. The spinodal temperature was estimated using the sidebands appearing in X-ray diffraction patterns in addition to the temperature dependence of magnetization values. This spinodal decomposition was accompanied by the oxidation of Fe2+ to Fe3+ and produced a unique grid-like microstructure (with a grid width of approximately 25 nm) along with enhancement of the saturated magnetization of the material. A sample cooled to room temperature in a furnace after heating at 1573 K in air had a lamella structure having a width of approximately 0.1 µm and comprised particles with a mixture of γ-Fe2O3 and the Fe-poor spinel compound on their surfaces. Subsequent heating of this same material to 1373 K in air formed ε-Fe2O3 in the particles. The crystallographic relationship between ε-Fe2O3 and the modified spinel structure compound was aε // [112Ì ]s, bε // [1Ì 10]s, and cε // [111]s (where ε and s indicate the ε-Fe2O3 and spinel, respectively).
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This paper describes the formation mechanism of monophasic Al3BC3 powder with hexagonal plate-like morphology using Al, B4C, and C powders in a stoichiometric ratio. For the synthesis of pure Al3BC3 by the conventional solid-state reaction method, it is important to avoid contamination from the starting powders. Thermogravimetry-differential thermal analysis curves and quantitative analysis by inductively coupled plasma-atomic emission spectroscopy revealed that there was no vaporization of the powder mixture during heating up to 1470 °C in a high-purity argon atmosphere. We found that the phases and Al3BC3 particle morphology after heating at 1800 °C strongly depended on the mixing conditions. In the case of a two-step process (remixing and reheating the sample), particles with random morphology were observed. On the other hand, well-faceted Al3BC3 particles were predominantly formed in a one-step process that involved heating after ball-milling for 24 h.
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Traditional Japanese Bizen stoneware is produced by firing a specific type of green clay in a wood-fired kiln at approximately 1200 °C. During this process, single crystalline branched dendrite-like particles of Al-substituted ε-Fe2O3 (ε-Fe1.7Al0.3O3) with widths and lengths of approximately 15 and 30 µm, respectively, are formed on the surface of the ceramic. Composite particles consisting of ε-Fe2O3 epitaxially connected to spinel structure compounds [comprising the Fe-substituted spinel (Mg,Fe)(Al,Fe)2O4 and γ-Fe2O3)] with lengths of approximately 3 µm are also generated. The present work clarified the crystallographic relationship between ε-Fe2O3 and the spinel structure compounds. In addition, brown-colored samples similar to Bizen pottery and with surface Al-substituted ε-Fe2O3 particles were prepared by heating clay with K2CO3 under a 10 vol % CO gas and 90 vol % Ar gas mixture using an electric furnace instead of a firewood kiln. Hence, a traditional method was adapted to achieve the industrial production of ε-Fe2O3 crystals.
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Patients with acute colorectal obstruction due to malignancy in the right-sided colon are treated with primary resection and anastomosis. However, considering the generally poor status and prognosis, less-invasive, palliative treatment is desirable, particularly for unresectable malignancies. An ileostomy is useful, but the patient must manage the stoma, which worsens the quality of life. We developed a palliative surgical procedure, termed the "Separation surgery of the right-sided colon," for treating an obstruction due to unresectable right-sided colon cancer. We identified and divided the ileum and the transverse colon and anastomosed the upper ileum to the lower transverse colon. Then, we created a mucous fistula with the loose ends of the lower ileum and the upper transverse colon. We performed this procedure in five patients. Stoma pouches were unnecessary. No comorbidities were observed, including anastomotic leakage. The "Separation surgery of the right-sided colon" was useful as palliative surgery.
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INTRODUCTION: The erythrocyte sedimentation rate (ESR) is a nonspecific inflammation indicator. In laboratory testing, automated ESR analyzers may use the reference Westergren method (Reference WG), modified Westergren (Modified WG), or Alternate ESR method (Alternate ESR) based on photometric rheology. A prototype hematology analyzer Celltac α+ (Nihon Kohden Corporation) with built-in Novel ESR analysis technology (Novel ESR) was developed to improve the accuracy of Alternate ESR. Alternate ESR uses only the aggregation phase information of Reference WG. The Novel ESR adds sedimentation and packing phase information obtained by hematology analyzer measurands. High correlation with WG was ensured by predicting the ESR value using Hematocrit (Hct) and MCV values as correcting parameters. METHODS: Novel ESR was compared with Modified WG (MONITOR-40, Joko Corporation) and Reference WG, according to internationally recognized guidelines: Precision, carryover, limit of quantification, comparability, linearity, accuracy, and fibrinogen sensitivity. Samples from healthy volunteers and clinical patients were used. The correction performance of Novel ESR and Modified WG was compared with Reference WG by regression analysis in three range categories for ESR and measurands affecting ESR correction (Hct, MCV, and MCH). RESULTS: Novel ESR showed sufficient basic performance and comparability with Modified WG. In the accuracy study comparing with Reference WG, the regression equation was y = 1.026x + 0.5(r = .945,P < .001;n = 271). When evaluating the correction performance, the slopes were within 0.8-1.2, except for the high part of Hct. All intercepts were within 10 mm. CONCLUSION: This study validated the correction performance to the initial estimated ESR value by aggregation phase information using information reflecting sedimentation and packing phase obtained from automated hematology analyzer. The Celltac α+ Novel ESR provided results equivalent to Reference WG.
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Sedimentação Sanguínea , Feminino , Hematócrito/instrumentação , Humanos , MasculinoRESUMO
BACKGROUND: Repeat liver resection is an effective treatment approach for patients with recurrent hepatocellular cell carcinoma (HCC). However, the surgical feasibility and oncological significance of repeat laparoscopic liver resection (r-LLR) remain unproven. This study evaluates and compares the clinical outcomes of non-anatomic r-LLR applied towards recurrent HCC, with those of primary LLR (p-LLR) for primary HCC. METHODS: This retrospective study reports 104 patients with HCC, treated with LLR between 2014 and 2018. Twenty eight of these patients underwent r-LLR for recurrent HCC. The clinical and surgical variables were reviewed for all cases. RESULTS: The analysis was limited to non-anatomic resection across both groups (r-LLR: 89% (25/28) vs. p-LLR: 80% (61/76)). There were no statistically significant differences about patient background between the two groups, with the exception of Child-Pugh classification. r-LLR surgical techniques included single-site laparoscopic adhesiolysis (32%, 8/25), Pringle maneuver (8%, 2/25), and crush-clamp method using BiClamp for hepatic parenchymal transection (72%, 18/25). No severe postoperative complications were observed in the r-LLR group. Postoperative hospital stays and procedure-related postoperative survival were similar for both groups. CONCLUSIONS: Non-anatomical r-LLR renders comparable surgical and oncological outcomes. Our data suggest that non-anatomical r-LLR is a safe and feasible therapeutic approach to recurrent HCC.
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Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Neoplasias Hepáticas/cirurgia , Idoso , Feminino , Humanos , Masculino , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Anatomic variants of the biliary tree present challenges to surgical management during laparoscopic cholecystectomy and affect perioperative outcomes. An aberrant right hepatic duct connecting into the cystic duct is a practically important variation because of the susceptibility to serious postoperative refractory bile leakage. We report a successful case of laparoscopic cholecystectomy in the aberrant right hepatic duct of a patient diagnosed with chronic cystitis. CASE PRESENTATION: A 49-year-old man was referred to our department for treatment of chronic cholecystitis. Magnetic resonance cholangiopancreatography indicated that the cystic duct branched from the common bile duct and an aberrant bile duct connected to the cystic duct. Intraoperative cholangiography revealed that the bile duct was not confluent to the major right branch of the intrahepatic bile duct and drained a narrow area. Preoperative magnetic resonance cholangiopancreatography had diagnostic value. Furthermore, intraoperative cholangiography with the Critical View of Safety method was paramount to achieving safe cholecystectomy based on confirmation of the biliary anatomy and the drainage area of the aberrant right hepatic duct. CONCLUSION: We encountered a rare but clinically significant case of laparoscopic cholecystectomy. This case suggests that precise understanding of the anatomy and drainage area of the aberrant right hepatic duct preoperatively and intraoperatively can lead to safe cholecystectomy.
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Extra-adrenal paraganglioma is a rare form of neuroendocrine neoplasm capable of catecholamine secretion. The surgical risks associated with the tumor location are compounded in this case of a kyphotic patient. This report presents the successful application of laparoscopy on extra-adrenal paraganglioma located behind the Spiegel lobe in a kyphotic patient. The operation was performed after 1 week of α-blocker administration. The laparoscopic approach, with the patient in the left hemilateral decubitus position on a rotating table, provided optimal access for safe tumor resection after complete hepatic right lobe mobilization. The patient's postoperative course was uneventful. Based on the results, the laparoscopic approach can be a safe and effective method for resecting extra-adrenal paraganglioma in the challenging case of a kyphotic patient.
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Cifose/complicações , Laparoscopia , Paraganglioma/complicações , Paraganglioma/cirurgia , Neoplasias Retroperitoneais/complicações , Neoplasias Retroperitoneais/cirurgia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Many members of the complex crystalline fluorite supercell structures (e.g. zirconolite, pyrochlore and murataite polytypes) have been considered/studied for possible long-term radioactive-waste immobilization. The eight-coordinated sites in these crystals are of particular importance because they are preferred for the accommodation of trivalent rare earths and actinides present in radioactive waste from fuel element processing. The fluorite-type supercell structures include the murataites, M3, M5, M7, M8, having those numbers of repeating fluorite sub-cell units. One simple technique, as shown here, namely the substitution of Hf into the Zr site, is very helpful for structural analysis in these very complex cases in order to further illuminate the site preference of the Zr ion. Three M3 murataite samples, Ca-Mn-Ti-Zr-Al-Fe-O (regular M3), Ca-Ti-Zr-Al-Fe-O (Mn-free M3) and Ca-Mn-Ti-Hf-Al-Fe-O (Hf-substituted M3) are investigated and, through techniques described for larger cells, show that the Zr is very likely not to be hosted in the [6]Ti site in the M3 murataite structure, as suggested by Pakhomova et al. [(2013), Z. Kristallogr. Cryst. Mater. 228, 151-156], but more likely replaces the [8]Ca1 site and less likely the [8]Ca2 site. This adjusted site preference for each cation from the powder X-ray diffraction (PXRD) and scanning transmission electron microscopy electron energy-loss spectroscopy (STEM-EELS) methods, agrees well with the high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) image.
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BACKGROUND: Countries in the Southeast Asia region have a high prevalence of soil-transmitted helminth, such as roundworm, whipworm, and hookworms [Ancylostoma duodenale, Necator americanus, Ancylostoma ceylanicum]. Recent molecular-based surveys have revealed that A. ceylanicum, a zoonotic hookworm, is likely the second most prevalent hookworm species infecting humans in that part of the world, while others have noted that this infection is an emerging public health risk not only for indigenous people but also for visitors from other countries. CASE PRESENTATION: We recently encountered four cases of A. ceylanicum infection in Japanese individuals who returned from Southeast Asia and Papua New Guinea. Case 1 was a 25-year-old male who stayed in a rainforest in Malaysia for 4 weeks, where he developed abdominal pain and diarrhea in the third week. Eleven adult worms (five males, six females) were expelled after treatment with pyrantel pamoate and identified as A. ceylanicum based on morphological characteristics and DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Case 2 was a 26-year-old male who spent 2 years as an overseas cooperation volunteer for agriculture in Papua New Guinea. He did not note any symptoms at that time, though eggs were detected in feces samples at a medical check-up examination after returning. Although collection of adult worms was unsuccessful, DNA analysis of the eggs for cox1 and the ribosomal internal transcribed spacer (ITS)-1 and ITS-2 genes demonstrated that they were A. ceylanicum. Case 3 was a 47-year-old male who spent 1 month in a rural village in Lao People's Democratic Republic and began suffering from watery diarrhea from the third week. A total of nine adult worms (three males, six females) were collected by endoscopic procedures and following treatment with pyrantel pamoate. Morphological examination and molecular analyses of the cox1 gene showed that they were A. ceylanicum. Case 4 was a 27-year-old male who participated in group travel to India for 5 days. Three weeks after returning, he developed abdominal pain and diarrhea. Hookworm eggs were found in feces samples and developed into larvae in culture, which were identified as A. ceylanicum based on molecular analysis of the cox1 gene. Eosinophilia was observed in all of the cases prior to treatment. CONCLUSIONS: A. ceylanicum should be recognized as an important etiologic pathogen of hookworm diseases in travelers to countries in the Southeast Asia and West Pacific Ocean regions.
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A 57-year-old female underwent abdominoperineal resection for rectal cancer. Although she received postoperative adjuvant chemotherapy, she had presacral recurrence with pain 26 months postoperatively. We provided palliative care in parallel with systemic chemotherapy, but she had difficulty controlling pain despite using high-dose opioids at 43 months after surgery. Multimodal therapy contributed to a reduction in opioid use for a brief time. Nevertheless, she required high-dose opioid therapy again at 50 months after the procedure. Since she used a rescue dose for relieving anticipatory anxiety for pain, we estimated that she developed chemical coping. After we tried analgesic adjuvant therapy and psychotherapy, her opioid use was reduced. For 10 months afterward, her disease worsened with time, but her pain was well-controlled. In cases where it is difficult to control pain, protection against exacerbation or opioid dose escalation should be considered. Furthermore, psychological contexts, including chemical coping, should also be considered. It may lead to the use of a proper dose of opioids and improve quality of life for patients.