Rooftop and on-road measurements of O3, NO2, NOx, and CO concentrations were conducted to investigate the relationship between rooftop and on-road concentrations in a busy and shallow street canyon ...with an aspect ratio of ∼0.3 in Seoul, Republic of Korea, from 15 April to 1 May 2014. The median road-to-roof concentration ratios, correlation coefficients between rooftop and on-road concentrations, and temporal variations of rooftop and on-road concentrations are analyzed according to the rooftop wind directions which are two cross-canyon and two along-canyon directions. The analysis results indicate that the relationship is strong when the rooftop is situated on the downwind side rather than on the upwind side. Relative to the cross-canyon wind directions, one of the along-canyon wind directions can more enhance the relationship. A conceptual framework is proposed to explain the effect of ambient wind direction on the relationship between rooftop and on-road concentrations in a street canyon.
One of the along-canyon wind directions can enhance the relationship between rooftop and on-road concentrations of traffic-related pollutants in a busy and shallow street canyon.
Phenomena observed in nature can be considered to be the result of optimized outcomes that have been obtained through trial and error for many years. Researchers have thus attempted to apply the ...lessons provided by nature to real scientific problems. In particular, in nature, the fluidic behavior of eddy currents is frequently observed, such as in a river, whereby the eddy develops into a whirlpool with an increased flow velocity, vorticity, and inner pressure. However, in this study on the design of a cathode for Li-air batteries (LABs), the eddy current of oxygen gas as a fluid can also be found in the gas diffusion layer (GDL) in the cathode fabricated using an imprinting process with micro-scale patterned metal molds. Herein, the cathode with the patterned GDL containing an increased density of carbon paper exhibits increased velocity, vorticity, and inner pressure of O
2
flow due to the increased eddy current effect (the inner structuring). In addition, the patterned cathode increases the catalytic active sites for the oxygen reduction reaction due to the outer structuring effect such as an increased roughness factor. According to the simulated data from COMSOL, an average O
2
gas velocity of the patterned cathode prepared through inner/outer structuring is increased by 45.8%, compared to that of the bare electrode. In the LAB test, the micro-scale patterned cathode shows an increased energy density and decreased
IR
drop by 79.6% and 23.2%, respectively. Consequently, the inner and outer structured GDL in the cathode for the ORR could be predominantly responsible for the superior LAB performance.
The patterned cathode exhibits improved high-rate performance.
Central venous catheters are used for various purposes in the operating room. Generally, the use of ultrasound to insert a central venous catheter is rapid and minimally complicated. An advanced ...venous access (AVA) catheter is used to gain access to the pulmonary artery and facilitate fluid resuscitation through the internal jugular vein. The present report describes a case in which ultrasound was used in a 43-year-old man to avoid complications during insertion of an AVA catheter with a relatively large diameter. The sheath of the catheter was so thin that a dilator was essential to prevent it from folding upon insertion. Despite the use of ultrasound guidance, the AVA catheter sheath became folded within the patient’s internal jugular vein. Mechanical complications of central venous catheter insertion are well known, but folding of a large-bore catheter in the internal jugular vein has rarely been reported.
The effects of physicochemical modification of carbon nanotubes (CNTs) on the explosion dynamics of a nanobomb, comprising nitromethane confined in CNTs, were investigated using nonequilibrium ...reactive molecular dynamics and density functional theory (DFT) calculations. CNTs with chirality, nitrogen-doping, and monovacancy defect were utilized. All modifications commonly reduced the time for nanobomb bursting under thermal shock and led to an overall similar reaction pathway. Bursting time of chirality-modified nanobomb was shortened by inferior mechanical property, whereas nitrogen-doping and monovacancy modification reduced the time by increased chemical reactivity (i.e., facilitated attachment of reaction intermediates to the nanocontainer). DFT calculations showed that nitrogen-doping and introducing monovacancy defects lowered the activation energy and heat of formation of the Stone–Wales defects and induced high binding energy of the intermediates, whereas chirality modification alone was ineffective. In addition, decomposition of the nanobomb was initiated via another two heating methods (i.e., electric spark and electromagnetic induction). Under a continuous electric field, bursting of nanobomb with electromagnetic induction was much faster due to oscillating frequency. This theoretical exploration of the effects of physicochemical modification of the nanocontainer and the explosion-initiation methods on the explosion of nanobombs provides in-depth understanding of a confined nanostructured high-energy material.
Objective:
To compare the frequency and pattern of cognitive impairment (CI) between patients with neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS).
Methods:
A total of 82 ...NMOSD patients, 58 MS patients, and 45 healthy controls (HCs) underwent a neuropsychological assessment.
Results:
CI was observed in 29% of NMOSD and 50% of MS patients (p < 0.001); CI was considered present if a patient scored lower than the fifth percentile compared with HCs in at least three domains. A lower frequency of CI was consistently found when CI was indicated by at least two failed tests (p < 0.001). MS patients performed worse than did NMOSD patients on verbal learning and verbal and visual memory tests. Levels of education and depression and the interval from disease onset to treatment were associated with a negative influence on cognition in patients with NMOSD.
Conclusion:
CI in patients with NMOSD may be not as common as in patients with MS. MS patients exhibited severe impairment, particularly on learning and memory tests, compared with NMOSD patients. Differential prevalence and patterns of CI between NMOSD and MS patients suggest that the two diseases have different mechanisms of brain injury.
This study aimed to evaluate the hypothesis that relief of nasal obstruction in subjects with obstructive sleep apnea (OSA) would lead to reduce OSA severity and to discuss the available evidence on ...the clinical efficacy of nasal surgery as a treatment modality for OSA.
Twenty-five subjects who had reduced patency of nasal cavity and narrowing of retroglossal or retropalatal airways were diagnosed with OSA and underwent nasal surgery, such as septoplasty or turbinoplasty to correct nasal pathologies. The effect of the surgery on nasal patency was quantified by measuring minimal cross-sectional area (MCA) using acoustic rhinometry. The watch-PAT-derived respiratory disturbance index (RDI), apnea and hypopnea index (AHI), lowest oxygen saturation, and valid sleep time were measured before and after nasal surgery.
The present study shows that the AHI and RDI decreased significantly and the lowest oxygen saturation and valid sleep time rose after nasal surgery in 25 OSA subjects. In addition, a reduction in subjective symptoms was observed in subjects and mean MCA increased after nasal surgery. Fourteen subjects were classified as responders and 11 subjects as non-responders. Responders showed considerable improvement of their subjective symptoms and the AHI and RDI were significantly lower after surgery. We found that the changes between pre- and post-operative AHI and RDI values were minimal in 11 non-responders. However, daytime somnolence and REM sleep time improved after nasal surgery in non-responders.
Our study provides evidence that the surgical treatment of nasal pathology improves nasal airway patency and reduces OSA severity in 56% subjects. Furthermore, correction of nasal pathology appears to result in improved sleep quality in both responder and non-responders OSA subjects.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Contamination by radioactive strontium (⁹⁰Sr) is a significant environmental problem. Ureolytically driven calcium carbonate precipitation has been proposed for use in geotechnical engineering for ...soil remediation applications. In this study, 68 ureolytic bacterial strains were newly isolated from various environments. Of these, 19 strains were selected based on ureolytic activity shown when cultured on urea agar plates and identified through 16S rRNA gene sequencing. From these selected strains, Sporosarcina pasteurii WJ-2 (WJ-2) was selected for subsequent study. A simple method was developed to determine the effectiveness of microbially induced calcite precipitation (MICP). Unlike any other methods, it does not require advanced skills and sophisticated tools. Using this method, we were able to determine the ability of the bioconsolidated sand to retard the flow of crystal violet through the 25-mL column. Also, MICP by WJ-2 was evaluated for its potential to counteract Sr contamination in column experiments using natural sand. WJ-2-induced precipitation led to successful sequestration of approximately 80 % of the Sr from the soluble fraction of the sand. The utility of MICP in bioremediation was further confirmed through X-ray diffraction, scanning electron microscopy, and inductively coupled plasma mass spectrometry.
Abstract
BACKGROUND
It remains controversial whether carotid artery stenting (CAS) is needed in cases of tandem cervical internal carotid artery occlusion (cICAO) and intracranial large vessel ...occlusion (LVO).
OBJECTIVE
To investigate the efficacy and safety of CAS in combination with endovascular thrombectomy (CAS-EVT) in cICAO-LVO patients and to compare its outcomes with those of EVT without CAS (EVT-alone).
METHODS
We identified all patients who underwent EVT for tandem cICAO-LVO from the prospectively maintained registries of 17 stroke centers. Patients were classified into 2 groups: CAS-EVT and EVT-alone. Clinical characteristics and procedural and clinical outcomes were compared between 2 groups. We tested whether CAS-EVT strategy was independently associated with recanalization success.
RESULTS
Of the 955 patients who underwent EVT, 75 patients (7.9%) had cICAO-LVO. Fifty-six patients underwent CAS-EVT (74.6%), and the remaining 19 patients underwent EVT-alone (25.4%). The recanalization (94.6% vs 63.2%, P = .002) and good outcome rates (64.3% vs 26.3%, P = .007) were significantly higher in the CAS-EVT than in the EVT-alone. Mortality was significantly lower in the CAS-EVT (7.1% vs 21.6%, P = .014). There was no significant difference in the rate of symptomatic intracranial hemorrhage between 2 groups (10.7 vs 15.8%; P = .684) and according to the use of glycoprotein IIb/IIIa inhibitor (10.0% vs 12.3%; P = .999) or antiplatelet medications (10.2% vs 18.8%; P = .392). CAS-EVT strategy remained independently associated with recanalization success (odds ratio: 24.844; 95% confidence interval: 1.445-427.187).
CONCLUSION
CAS-EVT strategy seemed to be effective and safe in cases of tandem cICAO-LVO. CAS-EVT strategy was associated with recanalization success, resulting in better clinical outcome.
Abstract
Background
Segmental fractures often result from high-energy or indirect trauma that causes bending or torsional forces with axial loading. We evaluated surgical outcomes of patients with ...forearm segmental diaphyseal fractures.
Methods
We retrospectively analyzed data from patients with forearm segmental fractures for which they underwent surgery at the Pusan National University Trauma Center from March 2013 to March 2022. We also analyzed accompanying injuries, injury severity score (ISS), injury mechanism, occurrence of open fracture, surgical technique, and treatment results.
Results
Fifteen patients were identified, one with bilateral segmental diaphyseal forearm bone fracture, for a total of 16 cases. Nine of the patients were male. The overall mean age was 50 years, and the mean follow-up period was 16.2 months. Six cases who underwent surgery using plate osteosynthesis achieved bone union without length deformity at final follow-up. Three of seven patients who underwent intramedullary nailing alone underwent reoperation due to nonunion. Six cases achieved bone union at final follow-up, three of which showed length deformity. Three patients underwent surgery using a hybrid method of IM nailing, plates, and mini cables. One patient who underwent surgery with a plate and one patient who underwent surgery with IM nailing alone showed nonunion and were lost to follow-up.
Conclusion
Plate osteosynthesis is considered the gold standard for treatment of adult forearm diaphyseal segmental fractures. In this study, IM nailing was associated with high rates of non-union and length deformity. However, the combination of IM nailing and a plate-cable system may be an acceptable alternative in segmental diaphyseal forearm fracture, achieving a union rate similar to that provided by plate fixation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To investigate the effect of choline alfoscerate (CA) on hearing amplification in patients with age related hearing loss, we performed a prospective case-control observational study from March 2016 ...to September 2020. We assessed patients with bilateral word recognition score (WRS) <50% using monosyllabic words. The patients were 65–85 years old, without any history of dementia, Alzheimer’s disease, parkinsonism, or depression. After enrollment, all patients started using hearing aids (HA). The CA group received a daily dose of 800 mg CA for 11 months. We performed between-group comparisons of audiological data, including pure tone audiometry, WRS, HA fitting data obtained using real-ear measurement (REM), and the Abbreviated Profile of Hearing Aid benefit scores after treatment. After CA administration, the WRS improved significantly in the CA group (4.2 ± 8.3%), but deteriorated in the control group (−0.6 ± 8.1%,
p
= 0.035). However, there was no significant between-group difference in the change in pure tone thresholds and aided speech intelligibility index calculated from REM. These findings suggest that the difference in WRS was relevant to central speech understanding rather than peripheral audibility. Therefore, administering oral CA could effectively enrich listening comprehension in older HA users.
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