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1.
Opt Express ; 26(14): 17781-17793, 2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-30114063

RESUMEN

An iterative algorithm based on optical path difference (OPD) and ray deflection is proposed to obtain the DT (deuterium-tritium)-layer refractive index and thickness of the ICF (inertial confinement fusion) target simultaneously. Starting from an assumed initial value, the refractive index and thickness are solved back and forth until the iteration stopping criterion is reached. Simulations show that the relative retrieval error of the DT-layer refractive index is better than 0.05% after finite iterations, and that of the thickness is better than 0.1%. Experiments show that the target shell refractive index and thickness can be retrieved with a relative error below ±2%. The test uncertainties from experiments were also analyzed.

2.
Opt Express ; 23(15): 19176-88, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26367580

RESUMEN

Instead of various mathematical stitching algorithms, an aspheric subaperture stitching interferometric method relying on modern computer modeling technique is presented. Based on our previously reported non-null annular subaperture stitching interferometry (NASSI), a simultaneous reverse optimizing reconstruction (SROR) method based on system modeling is proposed for full aperture figure error reconstruction. All the subaperture measurements are simulated simultaneously with a multi-configuration model in a ray tracing program. With the multi-configuration model, full aperture figure error would be extracted in form of Zernike polynomials from subapertures wavefront data by the SROR method. This method concurrently accomplishes subaperture retrace error and misalignment correction, requiring neither complex mathematical algorithms nor subaperture overlaps. Experiment results showing the validity of SROR method are presented.

3.
J Phys Chem A ; 119(12): 3035-47, 2015 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-25735627

RESUMEN

Although ammonium ion-water clusters are abundant in the biosphere, some information regarding these clusters, such as their growth route, the influence of temperature and humidity, and the concentrations of various hydrated clusters, is lacking. In this study, theoretical calculations are performed on ammonium ion-water clusters. These theoretical calculations are focused on determining the following characteristics: (1) the pattern of cluster growth; (2) the percentages of clusters of the same size at different temperatures and humidities; (3) the distributions of different isomers for the same size clusters at different temperatures; (4) the relative strengths of the noncovalent interactions for clusters of different sizes. The results suggest that the dipole moment may be very significant for the ammonium ion-water system, and some new stable isomers were found. The nucleation of ammonium ions and water molecules is favorable at low temperatures; thus, the clusters observed at high altitudes might not be present at low altitudes. High humidity can contribute to the formation of large ammonium ion-water clusters, whereas the formation of small clusters may be favorable under low-humidity conditions. The potential energy surfaces (PES) of these different sized clusters are complicated and differ according to the distribution of isomers at different temperatures. Some similar structures are observed between NH4(+)(H2O)n and M(H2O)n (where M represents an alkali metal ion or water molecule); when n = 8, the clusters begin to form the closed-cage geometry. As the cluster size increases, these interactions become progressively weaker. The successive binding energy at the DF-MP2-F12/VDZ-F12 level is better than that at the PW91PW91/6-311++G(3df, 3pd) level and is consistent with the experimentally determined values.

4.
Clin Lab ; 61(11): 1727-35, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26731999

RESUMEN

BACKGROUND: To investigate the distribution of stenosis of intracranial and extracranial arteries of Han population patients suffering from cerebral infarction in the city of Quanzhou in Fujian and to determine the correlation of apolipoprotein A1 and apolipoprotein B with intracranial and extracranial atherosclerosis stenosis. METHODS: For this study, we enrolled patients with cerebral infarction between December 2009 and October 2012 at the Neurology Department of The Second Affiliated Hospital of Fujian Medical University. All patients were examined by computed tomography angiography (CTA). Past medical history, demographic data, and biochemical markers were collected. Multiple logistic regression analysis was used to study the association between apo A1, apo B, and cerebral atherosclerosis stenosis. RESULTS: A total of 412 patients were included in this study. 137 cases (33.3%) were classified as the intracranial atherosclerosis stenosis (ICAS) group, 74 cases (18.0%) as the combined intracranial and extracranial atherosclerosis stenosis (COAS) group, 44 cases (0.7%) as the extracranial atherosclerosis stenosis (ECAS) group, and 157 cases (38.1%) as the non-cerebral atherosclerosis stenosis (NCAS) group. Middle cerebral arteries (43.8%) were the most common lesions of intracranial arterial atherosclerosis stenosis. Extracranial carotid stenosis (30.7%) were more likely to be stenoses in the extracranial internal carotid arteries. Compared with the NCAS group, apo B was significantly higher (p < 0.001), apo A1 was significantly lower in the ICAS group and COAS group (p = 0.02 and p = 0.030). Compared with the mild atherosclerosis stenosis group, apo B was higher in the severe extracranial atherosclerosis stenosis group (p = 0.03), apo A1 was lower in the severe intracranial atherosclerosis stenosis group (p < 0.001). The multiple logistic regression analyses showed that when apo A1 > 1.28 g/L, it was an independent protective factor of intracranial stenosis (OR, 0.39), apo B was an independent risk factor of the cerebral atherosclerosis stenosis group, and when apo B > 1.16, it is significantly associated with the cerebral atherosclerosis stenosis group (ICAS: OR, 6.41) (ECAS: OR, 5.15). CONCLUSIONS: 1. The occurrence of atherosclerosis stenosis in intracranial arteries is more frequent than that in extracranial arteries in population with cerebral infarction; 2. Apo B is an independent risk factor of intracranial and extracranial arterial stenosis, apo A1 is associated with the degree of intracranial stenosis and an independent protector of intracranial stenosis.


Asunto(s)
Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Arterias/patología , Aterosclerosis/sangre , Arterias Cerebrales/patología , Accidente Cerebrovascular/sangre , Anciano , Estudios de Casos y Controles , Humanos , Persona de Mediana Edad
5.
Appl Opt ; 54(10): 2838-44, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25967197

RESUMEN

Traditional spherical radius of curvature interferometry is not valid for an aspheric vertex radius of curvature (VROC) due to the obstacle in identifying null positions (cat's eye or confocal position). Simultaneous optimization for multiconfiguration of an interferometer model is proposed to retrieve the actual aspheric VROC from its biased nominal value. This procedure works out the contradiction between VROC deviation and positioning error and even surface figure error, independent of absolute positioning by cat's eye or confocal position. In this method, the aspheric VROC and surface figure can be measured simultaneously, which facilitates the test process remarkably in practical optical shop testing. Furthermore, the parent VROC of a hollow aspheric (annular surface) also can be determined in this method. The performance of the proposed method is validated by experiments.

6.
Appl Opt ; 53(24): 5538-46, 2014 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-25321131

RESUMEN

Aspheric non-null testing, as an alternative to the traditional null testing, achieves more flexible measurements. However, figure-error reconstruction in non-null tests has always been difficult due to the presence of retrace error. A novel method with reverse optimization is proposed for aspheric figure-error reconstruction in a non-null interferometer. It is a generalized and effective approach based on system modeling and polynomial fitting. An optimization function is set with polynomial coefficients of the desired figure error as variables and those of the detected experimental wavefront as optimization targets. Through the reverse optimization process with iterative ray tracing, the optimal solutions can be extracted and the desired figure error is reconstructed with a simple fitting procedure. Numerical simulations verifying the high accuracy of the proposed method are presented with error considerations. A set of experiments has also been carried out to demonstrate the validity and repeatability of this method.

7.
Appl Opt ; 53(25): 5755-62, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25321374

RESUMEN

A non-null annular subaperture stitching interferometry (NASSI), combining the subaperture stitching ideal and non-null test method, is proposed for steep aspheric testing. Compared with standard annular subaperture stitching interferometry (ASSI), a partial null lens (PNL) is employed as an alternative to the transmission sphere, to generate different aspherical wavefronts as the references. The coverage subaperture number would be reduced greatly for the better performance of aspherical wavefronts in matching the local slope of aspheric surfaces. In this way, relatively large overlapping areas can be obtained for adjustment errors correction while the error accumulation would be decreased. With the reverse optimization reconstruction (ROR) method for retrace error correction, the figure error of each subaperture can be retrieved accurately. Therefore, the testing accuracy and efficiency are thus increased. The dynamic test range is extended as well. A numerical simulation exhibits the comparison of the performance of the NASSI and standard ASSI, which demonstrates the high accuracy of the NASSI in testing steep aspheric. Experimental results of NASSI are shown to be in good agreement with those of the Zygo interferometer.

8.
Appl Opt ; 52(35): 8501-11, 2013 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-24513893

RESUMEN

Calibration for misalignment aberrations is one of the challenges in non-null interferometric aspheric testing. The high-order misalignment aberrations are especially difficult to distinguish from the rest of the testing system. The traditional calibration method removing the first four terms from the Zernike coefficients of the test wavefront is obviously inaccurate. Computer-aided alignment is considered to be an effective method; however, it is less practical due to its dependency on mechanical or manual adjustment, as are other common methods. A practical and accurate calibration method based on system modeling is proposed in this paper for misalignment aberrations' removal. In this work, actual misalignments, which are calculated from five selected low-order aberrations of the test wavefront in the experiment, are simulated in the model to predict all misalignment aberrations by ray tracing. These aberrations then are removed by a simple wavefront data subtraction. The method depends on neither a precise adjusting mechanism nor a troublesome manual adjustment. Experimental results showing feasibility and repeatability of the proposed method are presented.

9.
Int J Clin Exp Pathol ; 8(3): 2461-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26045752

RESUMEN

MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs, which play a critical role in regulating varieties of the biological and pathologic processes. MiR-196a has been reported to take part in tumorigenic progression of osteosarcoma (OS). However, the effects of miR-196a on OS are still unclear. The objective of this study is to investigate the molecular mechanism of miR-196a in osteosarcoma cells. In the present study, the expression of miR-196a in OS cell lines was detected by real-time PCR. We found that the expression level of miR-196a was markedly up-regulated in osteosarcoma cell lines compared with normal osteoblastic cells. Then, the miR-196a mimic was transiently transfected into MG63 and U2OS cells using Lipofectamine™ 2000 reagent. Subsequently, the MTT and Brdu-ELISA results showed that up-regulation of miR-196a promoted the cell viability and proliferation. Our results also showed that miR-196a mimic accelerated cell cycle progression of MG63 and U2OS cells by down regulation of p21 and p27, and upregulation of cyclin D1. In addition, overexpression of miR-196a suppressed apoptosis of MG63 and U2OS cells due to increasing BCL2L2 and MCL-1 expressions, and then inactivating caspase-3. Eventually, the effect of miR-196a mimic on the PTEN/phosphoinositide 3-kinase (PI3K)/Akt signaling pathway was explored by Western blot. From our results, transfection of miR-196a decreased the expression of PTEN and increased the phosphorylation of PI3K and Akt. Taken together, miR-196a should be an oncogene in osteosarcoma. The possible mechanism was that overexpression of miR-196a promoted proliferation of MG63 and U2OS cells by modulating the PTEN/PI3K/Akt signaling pathway.


Asunto(s)
Apoptosis , Neoplasias Óseas/enzimología , Proliferación Celular , Factores de Transcripción Forkhead/metabolismo , MicroARNs/metabolismo , Osteosarcoma/enzimología , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proteína Forkhead Box O1 , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Osteosarcoma/genética , Osteosarcoma/patología , Fosfatidilinositol 3-Quinasa/metabolismo , Fosforilación , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Transfección , Regulación hacia Arriba
10.
World J Gastroenterol ; 21(12): 3759-62, 2015 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-25834348

RESUMEN

Gastritis cystica profunda is a relatively rare disease, usually observed at anastomotic sites in stomachs of patients that have undergone gastric procedures. We present the rare case of an elevated lesion in the anterior wall of the gastric antrum of a 43-year-old Chinese woman who had never undergone gastric surgery and had no gastrointestinal tract symptoms. Although the physical examination and laboratory data showed no abnormalities, endoscopic ultrasonography revealed an anechoic cystic structure. Abdominal computed tomography and magnetic resonance imaging showed the gastric wall of the greater curvature of the antrum was markedly and irregularly thickened, and mild to moderate enhancement was observed around the lesion with no enhancement in the central portion, suggestive of a gastrointestinal stromal tumor. The patient underwent a distal gastric resection of the 2.5 cm × 1.5 cm lesion. A postoperative pathologic examination showed dilated cystic glands in the muscularis mucosa and submucosal layers and erosion of the mucosal surface of the tumor, confirming the diagnosis of gastritis cystica profunda without malignancy.


Asunto(s)
Quistes/diagnóstico , Mucosa Gástrica/patología , Antro Pilórico/patología , Gastropatías/diagnóstico , Adulto , Biopsia , Quistes/patología , Quistes/cirugía , Endosonografía , Femenino , Gastrectomía , Mucosa Gástrica/diagnóstico por imagen , Mucosa Gástrica/cirugía , Gastroscopía , Humanos , Antro Pilórico/diagnóstico por imagen , Antro Pilórico/cirugía , Gastropatías/patología , Gastropatías/cirugía , Tomografía Computarizada por Rayos X
11.
Asian Pac J Cancer Prev ; 14(7): 4249-54, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23991985

RESUMEN

BACKGROUND: Parafibromin is a protein encoded by the HRPT2 (hyperparathyroidism 2) oncosuppressor gene and its down-regulated expression is involved in pathogenesis of parathyroid, breast, gastric and colorectal carcinomas. This study aimed to clarify the effects of parafibromin expression on the phenotypes and relevant mechanisms of DLD-1 colon carcinoma cells. METHODS: DLD-1 cells transfected with a parafibromin-expressing plasmid were subjected to examination of phenotype, including proliferation, differentiation, apoptosis, migration and invasion. Phenotype-related proteins were measured by Western blot. Parafibromin and ki-67 expression was detected by immunohistochemistry on tissue microarrays. RESULTS: The transfectants showed higher proliferation by CCK-8, better differentiation by electron microscopy and ALP activity and more apoptotic resistance to cisplatin by DNA fragmentation than controls. There was no difference in early apoptosis by annexin V, capase-3 activity, migration and invasion between DLD-1 cells and their transfectants. Ectopic parafibromin expression resulted in down-regulated expression of smad4, MEKK, GRP94, GRP78, GSK3ß-ser9, and Caspase-9. However, no difference was detectable in caspase-12 and -8 expression. A positive relationship was noted between parafibromin and ki-67 expression in colorectal carcinoma. CONCLUSIONS: Parafibromin overexpression could promote cell proliferation, apoptotic resistance, and differentiation of DLD-1 cells.


Asunto(s)
Apoptosis , Diferenciación Celular , Proliferación Celular , Neoplasias Colorrectales/patología , Proteínas Supresoras de Tumor/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/metabolismo , Western Blotting , Ciclo Celular , Movimiento Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Chaperón BiP del Retículo Endoplásmico , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/genética , Cicatrización de Heridas , Adulto Joven
12.
Chin Med J (Engl) ; 126(24): 4685-90, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24342312

RESUMEN

BACKGROUND: Thrombolysis with recombinant tissue plasminogen activator (rt-PA) has gained international recognition, clinical outcomes following this thrombolytic therapy varied from patient to patient. Factors affecting clinical outcomes have not been well understood yet, so this retrospective case-control study aimed to investigate factors that may influence clinical outcomes of acute ischemic stroke treated with intravenous rt-PA. METHODS: One hundred and one patients with acute ischemic stroke who received intravenous rt-PA thrombolysis within 4.5 hours from disease onset were included. Patients were divided into good or poor outcome group according to modified Rankin Scale (mRS) score, good outcome group: mRS score of 0-1; poor outcome group: mRS of 2-6. Stroke characteristics were compared between the two groups. Factors for stroke outcomes were analyzed via univariate analysis and Logistic regression. RESULTS: Of the 101 patients studied, patients in good outcome group (n = 55) were significantly younger than patients in poor outcome group (n = 46, (62.82 ± 14.25) vs. (68.81 ± 9.85) years, P = 0.029). Good outcome group had fewer patients with diabetic history (9.09% vs. 28.26%, P = 0.012), fewer patients with leukoaraiosis (7.27% vs. 28.26%, P = 0.005) and presented with lower blood glucose level ((5.72 ± 1.76) vs. (6.72 ± 1.32) mmol/L, P = 0.012), lower systolic blood pressure level ((135.45 ± 19.36) vs. (148.78 ± 19.39) mmHg, P = 0.003), lower baseline NIHSS score (12.02 ± 5.26 vs. 15.78 ± 4.98, P = 0.002) and shorter onset-to-treatment time (OTT) ((2.38 ± 1.21) vs. (2.57 ± 1.03) hours, P = 0.044) than poor outcome group. Logistic regression analysis showed that absence of diabetic history (odds ratio (OR) 0.968 (95% CI 0.941-0.996)), absence of leukoaraiosis (OR 0.835 (95% CI 0.712-0.980)), lower baseline NIHSS score (OR 0.885 (95% CI 0.793-0.989)), lower pre-thrombolysis systolic blood pressure (OR 0.962 (95% CI 0.929-0.997)), and lower blood glucose level (OR 0.699 (95% CI 0.491-0.994)) before thrombolysis were significantly associated with better outcome. CONCLUSION: Patients with no history of diabetes, no leukoaraiosis, low blood glucose level, low systolic blood pressure level and low baseline NIHSS score before thrombolysis have a better outcome.


Asunto(s)
Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , Presión Sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Terapia Trombolítica , Resultado del Tratamiento
13.
Zhongguo Zhen Jiu ; 26(5): 337-8, 2006 May.
Artículo en Zh | MEDLINE | ID: mdl-16739847

RESUMEN

OBJECTIVE: To observe therapeutic effect of blood-letting therapy on apoplectic hemiplegia numbness syndrome and search for clinically effective therapy. METHODS: Ninety and five cases of apoplectic hemiplegia were randomly divided into a treatment group of 55 cases and a control group of 40 cases in order of visiting. The treatment group were treated with tapping Huatuo Jiaji (EX-B2) on the back by plum-blossom needle combined with blood-letting on twelve Well-points or Shixuan (EX-UE 11), once every day, 6 times constituting one course; the control group were treated with routine acupuncture at points of the four limbs, once daily, 12 times constituting one course. After they were treated for 4 courses, their therapeutic effects were observed. RESULTS: The total effective rate was 94.5% in the treatment group and 77.5% in the control group with a significant difference between the two groups (P < 0.01). CONCLUSION: Blood-letting therapy is an effective therapy for post-apoplectic hemiplegia numbness syndrome.


Asunto(s)
Terapia por Acupuntura/métodos , Hemiplejía/terapia , Hipoestesia/terapia , Flebotomía , Accidente Cerebrovascular/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome
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