1.Magnetic properties and heavy metal contents of automobile emission particulates.
Sheng-gao LU ; Shi-qiang BAI ; Jing-bo CAI ; Chuang XU
Journal of Zhejiang University. Science. B 2005;6(8):731-735
Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission particulate samples indicated the presence of magnetic particles in them. The values of frequency dependent susceptibility (chi(fd)) showed the absence of superparamagnetic (SP) grains in the samples. The IRM(20 mT) (isothermal remanent magnetization at 20 mT) being linearly proportional to SIRM (saturation isothermal remanent magnetization) (R(2)=0.901), suggested that ferrimagnetic minerals were responsible for the magnetic properties of automobile emission particulates. The average contents of Cu, Cd, Pb and Fe in automobile emission particulates were 95.83, 22.14, 30.58 and 34727.31 mg/kg, respectively. Significant positive correlations exist between the magnetic parameters and the contents of Pb, Cu and Fe. The magnetic parameters of automobile emission particulates reflecting concentration of magnetic particles increased linearly with increase of Pb and Cu content, showed that the magnetic measurement could be used as a preliminary index for detection of Pb and Cu pollution.
Algorithms
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Environmental Monitoring
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methods
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Feasibility Studies
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Magnetics
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Metals, Heavy
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analysis
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chemistry
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Statistics as Topic
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Vehicle Emissions
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analysis
2.Perioperafive management of neurosurgical patients with recurrent epileptic seizures
Guan-Qian YUAN ; Dan-Dan GAO ; Jun LIN ; Song HAN ; Bo-Chuang LU ; Guo-Biao LIANG ; Xue-Zhong WEI
Chinese Journal of Neuromedicine 2011;10(11):1149-1151
Objective To investigate the clinical features of recurrent epileptic seizures and perioperative management principles and methods of neurosurgical patients with recurrent epileptic seizures.Methods The clinical data,reasons for aggravated seizures,seizure characteristics,and treatment methods and results of 9 patients with recurrent epileptic seizures were analyzed retrospectively.Results Of all the 9 patients,3 were combined with glioma,1 with arachnoid cyst,1 with cavernous hemangioma and 1 with encephalomalacia; epilepsy history was noted in 7 patients; frontal lobe epilepsy was noted in 7,and temporal lobe epilepsy in 2.The reasons for seizure aggravation included drug-decrement(n=3),recent-diagnosed brain tumor(n=2)and surgical operation during intracranial electrode implantation(n=1); and unknown reason was noted in the other 3.Epileptic seizure types included partial seizure and secondary generalized seizure; the frequency of seizure ranged from 3 minutes of interval to several hours of interval.Patients given multiple antiepileptic drugs,including oral and parenteral administration,received good seizure-control; and levetiracetam showed good curative effect during the treatment.Conclusion Recurrent seizures show drug refractory,and is hard to control.The AEDs having good curative effect in partial seizure should be combined used in these patients with higher dosage than conventional initial dose; intravenous and intramuscular administration can be used; the seizures should be controlled as soon as posible.Levetiracetam has good curative effect on patients with recurrent seizures for its fast oral-absorption,rapid onset of action and good antiepileptic effect.
3.Microvascular decompression in the treatment of cerebral neurovascular compression syndrome
Hong-Xing HUANG ; Shu-Cheng ZOU ; Chuang-Hua LI ; Qi-Chang ZENG ; Zong-Wan LUO ; Qin WANG ; Ling LI ; Jun LU ; Bo LIU ; Kun LIU
Chinese Journal of Neuromedicine 2009;8(12):1265-1267,1270
Objective To summarize and analyze the efficacy of microvascular decompression (MVD) for cerebral neurovascular compression syndrome and its postoperative complications. Methods MVD was performed in 39 patients with cerebral neurovascular compression syndrome, including 19 with trigeminal neuralgia, 18 with facial spasm and 2 with glossopharyngeal neuralgia. The surgical techniques and prevention of postoperative complications were analyzed. Results The immediate relief of pain was succeed in 17 with trigeminal neuralgia and 2 with glossopharyngeal neuralgia and the spasm was eliminated in 16 with facial spasm right after the operation. No hematoma, infection, cerebrospinal fluid leakage or death appeared and the total effectiveness rate was 94.87%. Follow-up was performed in 34 with an average of 1.58 years and 32 were recorded with good results. Conclusion MVD for cerebral neurovascular compression syndrome is safe, minimally invasive and effective. It is by far the first choice in the treatment of cerebral neurovascular compression syndrome.
4.Three-dimensional finite element analysis of Kirschner wire fixation configuration for supracondylar fracture of humerus fracture in children.
Xiang-Fei LIU ; Kamara ALLIEU ; Chuang LIU ; En-Bo WANG ; Xiang-Lu JI ; Tian-Jing LIU ; Qi-Lin LI
China Journal of Orthopaedics and Traumatology 2020;33(10):948-953
OBJECTIVE:
To establish a new mechanical model of distal humerus in children with epiphysial cartilage, stimulate supracondylar humerus fracture and perform three dimensional finite elements, and study effect of pins numbers, pin tract, outlet height and pin configurations on stability of fixation.
METHODS:
Three dimensional computed tomography (CT) data of 6-year-old boy with distal humerus was downloaded from picture archiving and communications systems software (PACS), the data of picture was imported into Simpleware and SolidWorks 2016 software to establish distal humerus fracture in children contained ossific nucleus of the capitellum (ONC) and distal cartilage. Normal extense supracondylar humerus fracture model was established to stimulate configurations of crossed and lateral pinning fixation, 30 N was added on the direction of flexion extension and varus valgus, while 50 N was added on the direction of internal and external turning. Stability was analyzed by displacement degree of distal fracture.
RESULTS:
Among 2-pin configurations, 2-crossed pins were more stable against rotation forces which could resist rotation stress over 2 585 Nmm/ °, while low position through ONC of 2-divergent lateral pins were more stable, which could resist stress of 45 N /mm and 190 N /mm during the test of resistant strains and varus-valgus stress. The third pins was added into the more stable lateral 2-pins, the stability in all directions were increased obviously, and 3 crossed pins is the most stable, stress of flexion-extension, varus-valgus and internal-external turning were 198 N /mm, 395 N /mm and 6 251 Nmm/ °.
CONCLUSION
Two-divergent lateral pins could provide enough stability for supracondylar humerus fracture in children. In two-crossed pins, the upper border of MDJ could provide the best stability. Three-crossed pins could offer the best stability against both translation and rotation forces.
Biomechanical Phenomena
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Bone Wires
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Child
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Finite Element Analysis
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Fracture Fixation, Internal
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Humans
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Humerus
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Male
5.Prognostic Value of Gai's Plaque Score and Agatston Coronary Artery Calcium Score for Functionally Significant Coronary Artery Stenosis.
Chuang ZHANG ; Shuang YANG ; Lu-Yue GAI ; Zhi-Qi HAN ; Qian XIN ; Xiao-Bo YANG ; Jun-Jie YANG ; Qin-Hua JIN
Chinese Medical Journal 2016;129(23):2792-2796
BACKGROUNDThe prognostic values of the coronary computed tomography angiography (CCTA) score for predicting future cardiovascular events have been previously demonstrated in numerous studies. However, few studies have used the rich information available from CCTA to detect functionally significant coronary lesions. We sought to compare the prognostic values of Gai's plaque score and the coronary artery calcium score (CACS) of CCTA for predicting functionally significant coronary lesions, using fractional flow reserve (FFR) as the gold standard.
METHODSWe retrospectively analyzed 107 visually assessed significant coronary lesions in 88 patients (mean age, 59.6 ± 10.2 years; 76.14% of males) who underwent CCTA, invasive coronary angiography, and invasive FFR measurement. An FFR <0.80 indicated hemodynamically significant coronary stenosis. Lesions were divided into two groups using an FFR cutoff value of 0.80. We compared Gai's plaque scores and CACS between the two groups and evaluated the correlations of these scores with FFR. The statistical methods included unpaired t-test, Mann-Whitney U-test, and Spearman's correlation coefficients.
RESULTSCoronary lesions with FFR <0.80 had higher Gai's scores than those with FFR ≥0.80. Gai's score had the strongest correlation with FFR (r = -0.48, P < 0.01) and had a greater area under the curve = 0.72 (95% confidence interval: 0.61-0.82; P < 0.01) than the CACS of whole arteries and a single artery.
CONCLUSIONSBoth CACS in a single artery and Gai's plaque score demonstrated a good capacity to assess functionally significant coronary artery stenosis when compared to the gold standard FFR. However, Gai's plaque score was more predictive of FFR <0.80. Gai's score can be easily calculated in daily clinical practice and could be used when considering revascularization.
Aged ; Computed Tomography Angiography ; Coronary Angiography ; Coronary Stenosis ; pathology ; Coronary Vessels ; pathology ; Female ; Fractional Flow Reserve, Myocardial ; physiology ; Humans ; Male ; Middle Aged ; Prognosis ; Retrospective Studies ; Vascular Calcification ; pathology