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BACKGROUND: We investigated the incidence and location of heterotopic ossification (HO) following hip arthroscopy. METHODS: This retrospective study enrolled 327 patients who underwent hip arthroscopy from January 2010 to December 2015. From this cohort, we extracted an HO group with simple radiographs or three-dimensional computed tomography (3D CT). Findings consistent with HO were classified according to the Brooker classification aided with 3D CT for the location of HO. The indication for revision arthroscopic excision of HO was painful, functional impairment of the hip. Patient clinical outcomes were assessed pre- and postoperatively, with modified Harris Hip Scores (mHHS), a visual analogue scale (VAS) for pain, and the Hip Outcome Score-Activity of Daily Living (HOS-ADL) and Sport Specific Subscales (HOS-SSS). RESULTS: In all, 14 (4.28%) of the 327 patients had confirmed HO radiographically. The mean follow-up was 39 months. In 13 patients, HO formed in the central area of the arthroscopic portals or capsulotomy. Ten patients had Brooker Grade 1 and four had Grade 2. At the last follow-up, 12 asymptomatic patients had significant (P < 0.001) improvements in all clinical outcome scores (mHHS, pain VAS, HOS-ADL, and HOS-SSS). Two patients developed symptoms sufficient to require revision hip arthroscopy for HO excision. After revision hip arthroscopy, both symptomatic patients had improved significantly in all clinical outcomes at the final follow-up. CONCLUSIONS: HO is a minor complication of hip arthroscopy, but sometimes induces severe pain and functional impairment. Usually, HO forms in the arthroscopic portal or capsulotomy area.
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Artralgia/epidemiologia , Artroscopia/efeitos adversos , Articulação do Quadril/cirurgia , Ossificação Heterotópica/epidemiologia , Adulto , Artralgia/diagnóstico , Artralgia/etiologia , Artralgia/cirurgia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/cirurgia , Medição da Dor , Reoperação , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: Infrapatellar fat pad (IPFP) syndrome and medial patellar plica (MPP) syndrome are two recognized causes of anterior knee pain. However, diagnosing these syndromes is challenging without arthroscopic examination. The aim of this study was to evaluate sagittal patellar tilt in patients with IPFP syndrome or MPP syndrome by measuring the patella-patellar tendon angle (PPTA) in affected patients. METHODS: Eighty-three patients with anterior knee pain who underwent diagnostic arthroscopy that confirmed isolated IPFP or MPP syndrome from 2011 to 2016 were included in this retrospective study. Patients were divided into Group A (IPFP syndrome, n = 44) and Group B (MPP syndrome, n = 39). The control group included 78 patients without knee pathology who underwent magnetic resonance imaging (MRI) of the knee during the study period. Radiographic measurements, including PPTA, IPFP area, patellar height, axial patellar alignment, patellar tilt, sulcus angle, and lateral trochlear inclination, were made on MRI images by two experienced sports medicine orthopedists. RESULTS: The mean PPTA in each knee-pathology group was significantly smaller than that in the control group (Group A: 137.3° ± 4.9°; Group B: 138.1° ± 3.2°; control group, 141.4° ± 2.9°). There was no significant difference between groups for any other radiographic parameter evaluated. CONCLUSION: The PPTA was significantly smaller in patients with IPFP syndrome or MPP syndrome than in healthy controls. Therefore, sagittal patellar tilt should be included in the routine evaluation of patients with anterior knee pain. Evaluation of PPTA may help to diagnose IPFP syndrome or MPP syndrome. LEVEL OF EVIDENCE: Level IV.
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Tecido Adiposo/patologia , Articulação do Joelho/patologia , Ligamento Patelar/patologia , Tecido Adiposo/diagnóstico por imagem , Adulto , Artralgia/etiologia , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Masculino , Ligamento Patelar/diagnóstico por imagem , Ligamento Patelar/cirurgia , Estudos Retrospectivos , Síndrome , Adulto JovemRESUMO
PURPOSE: We surgically treated subungual masses that were suspected glomus tumors, although definitive clinical and radiological findings were lacking. We report the outcomes of a retrospective case series. METHODS: Of 42 patients treated by surgical resection between March 1996 and December 2015, 7 who met our inclusion/exclusion criteria were evaluated. At least 1 symptom of the typical triad (temperature sensitivity, severe pain, and localized tenderness) was absent, and computed tomography (CT) and magnetic resonance imaging (MRI) findings were normal. After ultrasonographic evaluation, we resected the masses using a transungual approach or a nail-preserving method. After pathological confirmation of the diagnosis, we followed all patients for at least 2 years to evaluate tumor recurrence and nail deformity. RESULTS: In 5 patients, cold sensitivity was the only symptom; no physical finding was suggestive of a glomus tumor. Tenderness was evidenced by the 2 patients who lacked cold sensitivity. None of the 7 patients exhibited CT or MRI abnormalities, but small acoustic shadows were evident in 4 patients, and blood-rich nodules were noted in 2 patients. The mean diameter of the 7 tumors was 2.1 mm, and pathological examination revealed typical glomus bodies. No major surgery-associated complication developed during follow-up. The final mean visual analog scale score (assessing pain) improved to 0.3 from the mean preoperative value of 3.6. CONCLUSIONS: Small glomus tumors exhibit few traditional symptoms and signs and no definitive radiological CT/MRI finding. However, cold sensitivity alone is a powerful surgical indication, and occasionally, ultrasonographic findings are useful even in the absence of CT/MRI findings.
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Síndromes Periódicas Associadas à Criopirina , Dedos/diagnóstico por imagem , Dedos/cirurgia , Tumor Glômico/diagnóstico por imagem , Tumor Glômico/cirurgia , Doenças da Unha/diagnóstico por imagem , Doenças da Unha/cirurgia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgia , Adulto , Feminino , Humanos , MasculinoRESUMO
This paper proposes a second-order differential microphone array (DMA) that can continuously steer in the main lobe direction. First, a general response of the second-order DMA is derived as a linear combination of a monopole and dipoles. Nine- and seven-microphone systems are proposed to realize continuous steering of the second-order DMA. The proposed system synthesizes the steered beam pattern without requiring the phase shifter by using back-to-back cardioids. Simulation results show that the nine-microphone configuration yields a nearly constant and high white noise gain, but the seven-microphone configuration has the practical advantage that it requires fewer microphones.
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During a phone conversation, loud vocal emission from the far-end to the near-end space can disturb nearby people. In this paper, the possibility of actively controlling such unwanted sound emission using a control source placed on the mobile device is investigated. Two different approaches are tested: Global control, minimizing the potential energy measured along a volumetric space surface, and local control, minimizing the squared sound pressure at a discrete point on the phone. From the test results, both approaches can reduce the unwanted sound emission by more than 6 dB in the frequency range up to 2 kHz.
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Telefone Celular , Som , Acústica/instrumentação , Impedância Elétrica , Humanos , Ruído , Espectrografia do SomRESUMO
From 2009 to 2013, 80 oyster and 16 seawater samples were collected from the southern coast of Korea, including designated shellfish growing areas for export. The concentrations and bioaccumulation of heavy metals were determined, and a potential risk assessment was conducted to evaluate their hazards towards human consumption. The cadmium (Cd) concentration in oysters was the highest of three hazardous metals, including Cd, lead (Pb), and mercury (Hg), however, below the standards set by various countries. The metal bioaccumulation ratio in oysters was relatively high for zinc and Cd but low for Hg, Pb, arsenic, and chromium. The estimated dietary intakes of all heavy metals for oysters accounted for 0.02%-17.75% of provisional tolerable daily intake. The hazard index for all samples was far <1.0, which indicates that the oysters do not pose an appreciable hazard to humans for the metal pollutants of study.
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Contaminação de Alimentos/análise , Metais Pesados/análise , Ostreidae/metabolismo , Animais , Arsênio/análise , Cádmio/análise , Substâncias Perigosas , Humanos , Mercúrio/análise , República da Coreia , Medição de Risco , Água do Mar , Frutos do Mar , Poluentes Químicos da Água/análise , Zinco/análiseRESUMO
This paper describes a technique for designing a collection of beamformers, a "beamformer bank," that approximately produces a constant-amplitude panning law. Useful in multichannel audio recording scenarios, a point source will appear with energy above a specified sidelobe level in at most two adjacent beams, and the sum of all beam signals will approximate the source signal. A design method is described in which a specified sidelobe level determines beamwidth as a function of arrival direction and frequency, leading directly to the number and placement of beams at each frequency. Simulation results are presented verifying the proposed technique's performance.
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Tetraethylenepentamine (TEPA) embedded zeolite A crystals were synthesized by using TEPA and the preformed zeolite A precursor under the microwave irradiation. The presence of TEPA in zeolite A crystal was confirmed by TG analysis and FTIR, Raman spectra. The CO2 adsorptive behavior of TEPA embedded zeolite A samples was investigated by CO2 isotherms measured at 25 degrees C comparing with zeolite A. The optimum CO2 sorption capacity was found in the case of 7.5% TEPA embedded zeolite A, which showed 3.75 mmol g(-1) where as the zeolite A showed less CO2 adsorption capacity of 2.88 mmol g(-1). The adsorption capacity of TEPA embedded Zeolite A was sustained up to 90% during 4 cycles of temperature swing adsorption (TSA) from 40 degrees C to 140 degrees C, indicating that the TEPA embedded Zeolite A was found to be useful as one of the application to solid amine adsorbent for CO2.
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OBJECTIVE: Accurate correction is a prerequisite for the favorable outcomes of open-wedge high tibial osteotomy (OWHTO). However, previous studies have reported disappointing results regarding correction accuracy despite the use of intra-operative navigation, which implies that a certain factor other than bony components is involved in the inaccurate correction (mainly overcorrection). The joint-line convergence angle (JLCA) can represent soft tissue effects in OWHTO. This study tried to determine whether the postoperative change in the JLCA (∆JLCA) led to inaccurate correction. METHODS: Medical records of 78 OWHTO patients from 2005 to 2021 were retrospectively reviewed. The hip-knee-ankle angle (HKA) was measured with a positive value indicating varus alignment. Inaccurate correction was defined as postoperative HKA < - 3°. The JLCA was measured before and 6 months after surgery on long-standing hip-to-ankle radiographs, and ∆JLCA was defined as the difference between the preoperative and 6-month postoperative JLCAs. ∆JLCA was compared between the accurate correction group and the inaccurate correction group, and a receiver operating characteristic (ROC) curve was used to obtain the cutoff ∆JLCA at which the sensitivity and the specificity for inaccurate correction were maximized. Clinical outcomes were also compared between the groups using the knee injury and osteoarthritis outcome score (KOOS) at final follow-up (60.9 ± 53.3 months postoperatively). RESULTS: Of the 78 patients, inaccurate correction was noted in 10 patients. The overall preoperative and postoperative HKAs were 7.0 ± 3.1° and - 0.4 ± 1.5°, respectively. The accurate correction group and the inaccurate correction group had a difference in ∆JLCA (p = 0.010). However, no significant difference was found in the preoperative HKA (p = 0.529). An ROC curve showed that the cutoff ∆JLCA was 1.9°. In the patients having ∆JLCA ≥ 1.9°, the mean JLCA was 4.9 ± 1.6° preoperatively and 1.7 ± 1.2° postoperatively. In the other patients having ∆JLCA < 1.9°, the mean preoperative and postoperative JLCA were 2.5 ± 1.8° and 2.3 ± 1.8°, respectively. The difference in the preoperative JLCA was significant (p < 0.001). The postoperative KOOS subscales did not differ according to correction accuracy. CONCLUSION: Inaccurate correction in OWHTO, specifically valgus overcorrection, is associated with large ∆JLCA which represents the postoperative change of soft tissue effects. Overcorrection should be checked in cases of large preoperative JLCAs.
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Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteotomia/métodosRESUMO
BACKGROUND AND OBJECTIVE: Adding opioid to spinal anaesthetic provides additional analgesia during the postoperative period. The purpose of this study was to determine the dose of intrathecal hydromorphone necessary to achieve postoperative pain relief after arthroscopic knee surgery. METHODS: In a prospective, double-blinded parallel, placebo-controlled manner, 60 patients who were undergoing unilateral knee arthroscopy randomly received unilateral spinal anaesthesia with 0.5% hyperbaric bupivacaine 6 mg combined with 0.0, 2.5, 5.0 or 10.0 µg per 0.05 ml hydromorphone. Fifteen patients were assigned to receive each dose. The visual analogue pain scores (VAPSs) were measured at 30 min and 2, 4, 6, 12 and 24 h postoperatively, and the side-effects of hydromorphone were recorded. RESULTS: The postoperative VAPSs at 4, 6 and 12 h for the 5 and 10 µg hydromorphone groups were significantly decreased, compared to the control group. The 2.5 µg hydromorphone group had lower VAPS only at 4 and 6 h postoperatively. Nausea was significantly increased in the 10 µg hydromorphone group (46.6%). CONCLUSION: The analgesic effects of 5 and 10 µg intrathecal hydromorphone provided satisfactory pain relief for 12 h postoperatively and nausea increased significantly in a dose-dependent manner.
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Analgésicos Opioides/administração & dosagem , Raquianestesia , Anestésicos Locais/administração & dosagem , Artroscopia/efeitos adversos , Bupivacaína/administração & dosagem , Hidromorfona/administração & dosagem , Articulação do Joelho/cirurgia , Dor Pós-Operatória/prevenção & controle , Adulto , Analgésicos Opioides/efeitos adversos , Distribuição de Qui-Quadrado , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Hidromorfona/efeitos adversos , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Placebos , Náusea e Vômito Pós-Operatórios/etiologia , Estudos Prospectivos , República da Coreia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Low sulfur fuel oils (LSFOs) with less than 0.5% sulfur content have been mandated for marine vessels by the International Maritime Organization since 2020. However, owing to the low dispersibility and high viscosity of LSFOs, their oceanic spills are difficult to clean using conventional response systems. In this study, we propose a superhydrophilic and hygroscopic ramie to clean spilled LSFO. To this end, a raw ramie fiber, which is intrinsically hydrophobic, was treated using a mild alkali to remove its waxy, rough, and gummy veneer and reveal a smooth surface. This substantially improved its hygroscopic nature, superhydrophilicity, and water-retention, while preserving its mechanical durability in dry and wet environments. The hygroscopic ramie exhibited underwater superoleophobicity and self-cleaning abilities against highly adhesive LSFOs. Two proofs-of-concept are demonstrated in this study-an oil-proof glove for maximizing oil repellency and a direct oil-scooping device for simple and continuous recovery of spilled oil with high efficiency.
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Boehmeria , Óleos Combustíveis , Interações Hidrofóbicas e Hidrofílicas , Enxofre , ViscosidadeRESUMO
The purpose of this study is to determine 1) whether morphine post condition (MPostC) can attenuate the intercellular adhesion molecules-1 (ICAM-1) expression after reoxygenation injury and 2) the subtype(s) of the opioid receptors (ORs) that are involved with MPostC. Human umbilical vein endothelial cells (HUVECs) were subjected to 6 hr anoxia followed by 12 hr reoxygenation. Three morphine concentrations (0.3, 3, 30 µM) were used to evaluate the protective effect of MPostC. We also investigated blockading the OR subtypes' effects on MPostC by using three antagonists (a µ-OR antagonist naloxone, a κ-OR antagonist nor-binaltorphimine, and a δ-OR antagonist naltrindole) and the inhibitor of protein kinase C (PKC) chelerythrine. As results, the ICAM-1 expression was significantly reduced in the MPostC (3, 30 µM) groups compared to the control group at 1, 6, 9, and 12 hours reoxygenation time. As a consequence, neutrophil adhesion was also decreased after MPostC. These effects were abolished by co administering chelerythrine, nor-binaltorphimine or naltrindole, but not with naloxone. In conclusion, it is assumed that MPostC could attenuate the expression of ICAM-1 on endothelial cells during reoxygenation via the κ and δ-OR (opioid receptor)-specific pathway, and this also involves a PKC-dependent pathway.
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Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Morfina/farmacologia , Entorpecentes/farmacologia , Traumatismo por Reperfusão/metabolismo , Animais , Benzofenantridinas/farmacologia , Células Endoteliais/citologia , Endotélio Vascular/citologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Naloxona/farmacologia , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Isoformas de Proteínas/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Receptores Opioides/metabolismo , Transdução de Sinais/fisiologia , Veias Umbilicais/citologiaRESUMO
A large reservoir of bacterial lipopolysaccharide (LPS) is available in the colon and this could promote colon cancer metastasis by enhancing tumor cell adhesion, intravasation, and extravasation. Furthermore, adhesion molecules like ICAM-1, VCAM-1, and E-selectin play important roles in the adhesion of tumor cells to endothelium. This study was designed to determine whether morphine can attenuate the expressions of adhesion molecules up-regulated by the supernatant of LPS-stimulated HCT 116 colon cancer cells (LPS-Sup). In this study, we divided to three groups by cell-growth medium of human umbilical vascular endothelial cells (HUVECs): the control group was incubated in growth factor-free endothelial medium, the Sup group was incubated in the supernatant of HCT 116 cells (Sup), and the LPS-Sup group was incubated in LPS-Sup. To observe effect of morphine to the adhesion molecules expressions in the LPS-Sup group, we co-treated morphine with LPS or added it to LPS-Sup. Adhesion molecule expressions on HUVECs in all three groups were measured during incubation period. Consquentially, ICAM-1, VCAM-1, and E-selectin expressions on HUVECs were significantly lower when morphine was co-treated with LPS than not co-treated. Thus, we suggest that morphine affects the expressions of adhesion molecules primarily by attenuating LPS stimuli on tumor cells.
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Moléculas de Adesão Celular/metabolismo , Neoplasias do Colo/metabolismo , Morfina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Selectina E/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/toxicidade , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Oblique lumbar interbody fusion (OLIF) improves the spinal canal, with favorable clinical outcomes. However, it may not be useful for treating concurrent, severe central canal stenosis (SCCS). Therefore, we added biportal endoscopic spinal surgery (BESS) after OLIF, evaluated the combined procedure for one-segment fusion with clinical outcomes, and compared it to open conventional TLIF. Patients were divided into two groups: Group A underwent BESS with OLIF, and Group B were treated via TLIF. The length of hospital stay (LOS), follow-up period, operative time, estimated blood loss (EBL), fusion segment, complications, and clinical outcomes were evaluated. Clinical outcomes were measured using Visual Analog Scale (VAS) scores, Oswestry Disability Index (ODI) scores, and the modified Macnab criteria. All the clinical parameters improved significantly after the operation in Group A. The only significant between-group difference was that the EBL was significantly lower in Group A. At the final follow-up, no clinical parameter differed significantly between the groups. No complications developed in either group. We suggest that our combination technique is a useful, alternative, minimally invasive procedure for the treatment of one-segment lumbar SCCS associated with foraminal stenosis or segmental instability.
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PURPOSE: Although the number of hip arthroscopies is rapidly increasing in non-elderly patients, outcomes of this procedure in middle-aged patients are not well documented or clearly understood. The purpose of this study was to evaluate the clinical and radiological outcomes after hip arthroscopy in middle-aged patients with early osteoarthritis. MATERIALS AND METHODS: This retrospective study analyzed 189 patients with early osteoarthritis of various diagnoses aged 40 years or older who underwent hip arthroscopy between January 2010 and December 2015. Clinical (e.g., modified Harris hip score [mHHS], hip outcome score-activities of daily living [HOS-ADL], visual analogue scale [VAS] for pain, range of motion) and radiological (change of Tönnis grade) outcomes were assessed at a minimum of 3-year follow-up. RESULTS: The mean preoperative and final mHHS and HOS-ADL improved from 61.2 and 60.6 to 79.5 and 81.8, respectively, while the VAS pain score decreased from 6.3 to 3.2 (P<0.001). Although the mean range of internal rotation and flexion increased from 14.2 and 100.7° preoperatively to 30.4 and 110.6° at 1-year postoperatively, they decreased slightly to 27.4 and 105.4° at the final follow-up, respectively. Eight cases (4.2%) underwent revision arthroscopic surgery and three cases (1.6%) were converted to total hip arthroplasty. CONCLUSION: Patients with early-stage osteoarthritis of various diagnoses achieved improved clinical outcomes. Therefore, using hip arthroscopy in middle-aged patients with early osteoarthritis, it is possible to achieve good surgical options.
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This paper reports the newly measured experimental data for CO2 solubility in a blended aqueous solution of monoethanolamine (MEA) and 2-amino-2-methyl-propanol (AMP) at different amine mixing ratios (MEA/AMP/H2O = 9:21:70, 15:15:70, and 21:9:70 wt %) and working temperatures (323.15, 373.15, and 383.15 K). The successive substitution method was used for calculating the mole fractions of all molecules (four molecules) and electrolytes (three cations and four anions) from the equilibrium along with the material and charge balance equations (11 equations). The electrolyte nonrandom two-liquid (e-NRTL) model was used to investigate nonideality in the liquid phase. Using the abovementioned thermodynamic models, the partial pressures of CO2 in the gas phase, mole fractions of all components in the liquid phase, pH variations, heats of absorption, and cyclic capacities of CO2 according to the absorption/desorption temperature and the blending ratio of MEA/AMP were estimated.
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A 48-year-old man visited the emergency room with right hip pain that started abruptly while walking out of the bathroom. Computed tomography showed an intraosseous mass in the femoral neck. The patient had a 15-year history of gout and had numerous bilateral tophi in his hands, feet, knees, and elbows. After operation, we diagnosed a pathological fracture due to intraosseous tophi. Patients with hip pain who have many subcutaneous tophi and long-standing gout should be diagnosed carefully. Peri-hip joint pain caused by gout is uncommon, however, if a patient complains of pain, a simple X-ray may be required. If intraosseous tophi are present, appropriate treatment (e.g., strict hyperuricemia control with or without prophylactic internal fixation), may be required before fracture occurs.
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Isostructural [M2(DOBDC)(EG)2] (M = Mg, Co, Ni) frameworks are first synthesized by controlling the pH* in the reaction medium. Coordinated ethylene glycols form a hexagonal OH cluster, which works as a template to grow single crystals with high crystallinity. After the liberation of solvated molecules, [M2(DOBDC)] shows notably higher surface areas than the reported values and completely different CO2 and CO separation properties depending on the kinds of unsaturated metal. Therefore, breakthrough experiments using a CO2/CO mixed gas show that Mg-MOF has a longer breakthrough time for CO2 than for CO, whereas Co/Ni-MOFs have longer breakthrough times for CO than for CO2. Apart from CO2 and CO, other gases such as CH4, H2, and N2 were almost not adsorbed at all in these materials at 298 K. To reveal the role of unsaturated metal sites, CO2 and CO adsorption sites are unequivocally determined by single-crystal X-ray diffraction analysis. One of very interesting discoveries is that there are two CO2 and CO adsorption positions (sites A and B) in the hexagonal channels. Site A is the unsaturated metal center working as Lewis acidic sites, and site B is the secondary adsorption site located between two A sites. A close inspection of crystal structures reveals that unsaturated Co(II) and Ni(II) sites adsorb both CO2 and CO, whereas the unsaturated Mg(II) sites strongly capture only CO2, not CO. Density functional theory calculations elucidate the discrepancy in CO affinity: Co(II) and Ni(II) form strong π-back-donating bonds with CO via electron transfer from the d orbitals of the transition metals to the antibonding molecular orbitals of CO, whereas Mg(II) does not participate in electron transfer or orbital overlap with CO. This observation provides new insight into the synthesis of novel functional materials with high CO2/CO separation performance.
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BACKGROUND: After calcaneal fracture surgery, a short leg splint and cast are typically applied. However, these restrict joint exercises, which is inconvenient for patients. In addition, there is a risk of complications, such as pressure ulcers or nerve paralysis with a short leg cast. In this study, we evaluated clinical and radiological outcomes of the use of a specially designed calcaneal brace after calcaneal fracture surgery. METHODS: From among patients who underwent open reduction and internal fixation for calcaneal fracture between July 9, 2013 and May 31, 2017, 102 patients who wore a calcaneal fracture brace (group A) and 82 patients who wore a postoperative short leg cast (group B) were randomly chosen for this study. Radiological changes and clinical factors were compared between the two groups. After swelling at the surgical site decreased, a special calcaneal brace was applied to patients in group A. They were allowed to perform early weight bearing and joint motion. Patients in group B were immobilized in a short leg cast and were told to avoid weight bearing for 6 weeks. In each group, the Böhler's angle and Gissane's angle were measured and compared using postoperative and final follow-up radiographs. Pain (measured using a visual analogue scale [VAS]) and ankle joint range of motion (dorsiflexion, plantar flexion, eversion, and inversion) were measured serially until the final follow-up visit. RESULTS: There were no significant differences in the Böhler's angle or Gissane's angle between the two groups as measured postoperatively and at the final follow-up (paired t-test). Differences in the VAS pain score and eversion were also statistically nonsignificant between the two groups. However, group A had a significantly higher range of dorsiflexion (p = 0.021), plantar flexion (p = 0.012), and inversion (p = 0.045) of the ankle than group B (independent t-test). CONCLUSIONS: Application of the calcaneal fracture brace after open reduction and internal fixation of a calcaneal fracture not only maintained the fracture reduction but allowed for greater joint motion than the short leg cast. Thus, the calcaneal fracture brace can be considered an effective postoperative management option that enables early resumption of daily activities and facilitates postoperative joint motion.
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Braquetes , Calcâneo/cirurgia , Fixação de Fratura/métodos , Fixação de Fratura/estatística & dados numéricos , Fraturas Intra-Articulares/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/fisiopatologia , Traumatismos do Tornozelo/cirurgia , Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Calcâneo/fisiopatologia , Feminino , Fixação de Fratura/efeitos adversos , Fixação de Fratura/instrumentação , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Amplitude de Movimento Articular/fisiologia , Resultado do Tratamento , Suporte de Carga/fisiologia , Adulto JovemRESUMO
The influence of ultrasonication treatment on the catalytic performance of CuY zeolite catalysts was investigated for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate (DMC). The deammoniation method of NH4Y into HY zeolites was optimized and characterized by elemental analyzer, derivative thermogravimetry, Brunauer-Emmett-Teller (BET) analyzer, and powder X-ray diffractometry, revealing that the HY zeolite deammoniated at 400⯰C presented the highest surface area, complete ammonium/proton ion exchange, and no structure collapse, rendering it the best support from all the prepared zeolites. CuY zeolites were prepared via aqueous phase ion exchange with the aid of ultrasonication. Upon ultrasonication, the Cu+ active centers were uniformly dispersed in the Y zeolites, penetrating the core of the zeolite particles in a very short time. In addition to enhancing the Cu dispersity, the ultrasonication treatment influenced the BET surface area, acid amount, Cu+/Cu2+ ratio, and also had a relatively small impact on the Cu loading. Consequently, adequate exposure to ultrasonication was able to increase the conversion rate of methanol into dimethyl carbonate up to 11.4% with a comparable DMC selectivity of 23.7%. This methanol conversion is 2.65 times higher than that obtained without the ultrasonication treatment.