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Anomalous Emission And Carrier Effect of Fresh Porous Silicon

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Chemical Research in Chinese Universities 2002年第3期18卷 270-273页

作者： ZoU Bing-suo WU Zhen yu CAo Li DAI Jian-hua XIE Si-shen WANG Jian ping Mostafa ael-Sayed optical Lab Institute of PhysicsChinese Academy of SciencesBeijing 100080P.R.China Laser Dynamics Laboratory School of Chemistry and BiochemistryGeorgia Institute of TechnologyAtlantaGA30332-0400

The emission and Fourier transformation infrared spectra of freshly prepared porous silicon(PS) and the silicon wafer were examined. Increasing temperature generally led to a decrease in the emission intensities of the PS samples, however, the freshly prepared sample showed an unusually large and sudden increase in its emission intensity at the specific temperature at which the hydrogen ion conductivity in the silicon wafer increased. The o-H vibrations of the silicon wafer also showed a sudden decrease at the same temperature. These results are consistent with the assumption that the luminescence of fresh PS comes from the carrier bound exciton in its confined nanostructure.

关键词： Porous silicon Silicon wafer Carrier effect

Protective effect of Citrus reticulata peel extract against potassium dichromate-induced reproductive toxicity in rats

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Asian pacific Journal of Reproduction 2019年第6期8卷 267-275页

作者： Samir AE Bashandy omar A-H Ahmed-Farid Enayat Aomara Sayed ael-Toumy Josline YSalib Pharmacology Department National Research Centre33 El-Bohouth St.DokkiP.O.12622GizaCairoEgypt Physiology Department National Organization for Drug Control and ResearchCairoEgypt Pathology Department National Research CentreCairoEgypt Chemistry of Tannins Department National Research CentreCairoEgypt

objective:To study the protective effect of Citrus reticulata peel extract against potassium dichromate-induced reproductive impairment in male Wistar ***:A total of 35 male Wistar rats were equally divided into 5 *** control group orally received an equivalent volume of saline(1 mL);group 2 was given potassium dichromate at 10 mg/kg/body weight(b.w.)orally for eight weeks;group 3 and 4 orally received Citrus reticulata peel extract at 200 and 400 mg/kg/***,followed by treatment with potassium *** 5 was administered with 400 mg/kg/*** reticulata peel extract *** parameters including oxidative stress(malondialdehyde,antioxidant enzymes),sex hormones(testosterone,luteinizing hormone,follicle-stimulating hormone)and inflammation indexes(tumor necrosis factor-alpha,inter leukin 6)were *** characteristics(sperm morphology,motility and count)were also ***:The decrease of male sex hormones concentration in plasma(testosterone,luteinizing hormone),testicular antioxidant parameters(reduced glutathione,catalase,superoxide dismutase,carnitine),sperm motility and sperm count induced by potassium dichromate was mitigated by Citrus reticulata peel ***,the peel extract alleviated the increase of sperm abnormalities,follicle-stimulating hormone,testicular malondialdehyde,tumor necrosis factor-alpha and nitric oxide levels caused by potassium *** sections of rats treated with the potassium dichromate were characterized by some histopathological changes as disorganization of spermatogonial cell layers and deformation of Leydig cells.A positive immune-reaction for p53 was observed in testicular cells of the rats treated with potassium *** extract of Citrus reticulata peel improved the testicular histology and decreased p53 positive immune-reaction in potassium dichromate administered ***:Citrus reticulata peel extract can alleviate the reproductive toxicity t

关键词： Citrus reticulatapeel extract Potassium dichromate Sperm Testicular function oxidative stress Anti-inflammatory

Angle-to-angle and spur-to-spur distance analysis with high-resolution optical coherence tomography

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Eye and Vision 2020年第1期7卷 399-411页

作者： Robert Montés-micó Pedro Tañá-Rivero Salvador Aguilar-Córcoles María Ruiz-Santos María Dolores Rodríguez-Carrillo Ramón Ruiz-Mesa oftalvist Alicante and Jerez de la FronteraAlicanteSpain University of Valencia ValenciaSpain

Background:To measure angle-to-angle(ATA)and spur-to-spur(STS)distances along six meridians using highresolution swept-source optical coherence tomography(SS-oCT)and to compare those values with horizontal white-to-white(WTW)***:68 eyes from 68 patients were quantitatively assessed with the Anterion SS-oCT(Heidelberg Engineering,Heidelberg,Germany).ATA and STS distances were measured with the SS-oCT’s B-Scan in six cross-sectional images corresponding to the vertical(6-12 o’clock),1-7 o’clock,2-8 o’clock,horizontal(3-9 o’clock),4-10 o’clock and 5-11 o’clock *** was measured horizontally with the device’s infrared camera.A Pearson correlation analysis was carried out to compare ATA and STS distances with ***:The largest values were found for the vertical meridian and the shortest for the 2-8 o’clock meridian,both for ATA and STS *** statistically significant differences were found between WTW,ATA and STS along the horizontal meridian(p>0.1).However,ATA and STS showed statistically significant differences elsewhere,except for the horizontal and the 2-8 o’clock meridians(p>0.05).Moreover,we found that ATA and STS varied significantly depending on the meridian being assessed,except for ATA at 4-10 versus 3-9 o’clock and for STS at 4-10 versus 3-9 o’clock and at 3-9 versus 2-8 o’clock(p>0.1).R^(2) values ranged from 0.49 to 0.75 for ATA and STS at the different meridians,showing the best correlation at 3-9 o’clock meridian(0.64 and 0.75,respectively)and the worst at 6-12 o’clock meridian(R^(2)=0.49 for both ATA and STS).Conclusions:ATA and STS distances vary radially,thus showing that the anterior chamber is vertically ***,it is advisable to measure these two distances along the meridian to be used.

关键词： Angle-to-angle Spur-to-spur White-to-white optical coherence tomography Swept-source Fourier domain

In situ XRD and electrochemical investigation on a new intercalation-type anode for high-rate lithium ion capacitor

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Journal of Energy Chemistry 2021年第6期30卷 109-117,I0004页

作者： Bobo Zou Ting Wang Shengyuan Li Rong Kang Guochun Li Sherif ael-Khodary Dickon HLNg Xianhu Liu Jingxia Qiu Yan Zhao Jiabiao Lian Huaming Li Institute for Energy Research Jiangsu UniversityZhenjiang 212013JiangsuChina Nanyang Environment and Water Research Institute(NEWRI) Interdisciplinary Graduate School(IGS)Nanyang Technological University50 Nanyang Avenue639798Singapore Department of Physics The Chinese University of Hong KongShatinHong KongChina Key Laboratory of Materials Processing&Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina

A new intercalation-type anode material is reported herein to improve the lithium storage kinetics for high-rate lithium ion *** crystal structure of orthorhombic NaNbo3 indicates two possible tunnels for lithium ions insertion into NaNbo3 host along theand***,in situ XRD is conducted to investigate the lithium storage mechanism and structural evolution of the NaNb o_(3) anode,demonstrating its intercalation behavior through(101)and(141)***,the rGo nanosheets are introduced to facilitate the charge transfer,which also effectively prevent the aggregation of NaNbo3 *** expected,the NaNbo_(3)/rGo nanocomposites possess remarkable reversible capacity(465 mA h g^(-1) at 0.1 A g^(-1)),superior rate capability(325 mA h g^(-1) at 1.0 A g^(-1))and cycling stability,attributed to their synergistic effect and high Li+diffusion coefficient DLi[D(NaNbo_(3)/rGo)/D(NaNbo_(3))≈31.54].Remarkably,the NaNbo3/rGo-based LIC delivers a high energy density of 166.7 W h kg^(-1) at 112.4 W kg^(-1) and remains 24.1 W h kg^(-1) at an ultrahigh power density of26621.2 W kg^(-1),with an outstanding cycling durability(90%retention over 3000 cycles at 1.0 A g^(-1)).This study provides new insights on novel intercalation-type anode material to enrich the materials system of LICs.

关键词： Lithium ion capacitor Intercalation-type anode NaNbo3 nanocubes In situ XRD High energy/power densities

Antibacterial potency of methanol extracts of lower plants

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第3期8卷 189-191页

作者： oJo o.o. AJAYI A.o. ANIBIJUWoN I.I. Department of microbiology Faculty of Science University of Ado-Ekiti Ado-Ekiti Ekiti State 234030 Nigeria

Antibacterial potency of methanol extracts of three green lower plants, Pneumatopteris afra, Platycerium bifurcatum and Nephrolepsis bisserata was determined using agar dilution method on clinical strains of Escherichia coli, Staphylococcus aureus, Klebsiella spp. and Salmomelia typhi. Antibacterial activities were observed at concentrations of 12.5, 25.0, 50.0 and 100.0 μg/ml. Their minimum inhibitory concentrations ranged from 12.5~100 μg/ml. Extracts of P. afra and P. bifurcatum were most active. Antibacterial activities observed with N. bisserata were less pronounced with no detectable activity at extract con-centrations of 12.5 and 25.0 μg/ml. E. coli, together with S. aureus appeared to be the most susceptible of the test bacteria while Klebsiella spp. was least sensitive. The significance of our findings is discussed.

关键词： Lower plants Extracts Antibacterial activity mic (minimum inhibitory concentration)

Focal depth,magnitude,and frequency distribution of earthquakes along oceanic trenches

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Earthquake Science 2013年第2期26卷 75-82页

作者： o.S.Hammed o.I.Popoola A.A.Adetoyinbo M.o.Awoyemi G.o.Badmus o.B.ohwo Bells University of Technology University of Ibadan obafemi Awolowo University Afe Babalola University

The occurrence of earthquakes in oceanic tren- ches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes along the trenches is needed to investigate the future occurrence of earthquakes in the zones. The oceanic trenches studied, were located from the seismicity map on： latitude ＋51 ° to＋53° and longitude -160° to 176° （Aleutian Trench）, latitude ＋40° to ＋53° and longitude ＋148° to＋165° （Japan Trench）, and latitude -75° to -64° and longitude -15° to ＋30° （Peru-Chile Trench）. The following features of seis- mic events were considered： magnitude distribution, focal depth distribution, and time distribution of earthquake. The results obtained in each trench revealed that the earthquakes increased with time in all the regions. This implies that the lithospheric layer is becoming more unstable. Thus, tectonic stress accumulation is increasing with time. The rate of increase in earthquakes at the Peru-Chile Trench is higher than that of the Japan Trench and the Aleutian Trench. This implies that the convergence of lithospheric plates is higher in the Peru-Chile Trench. Deep earthquakes were observed across all the trenches. The shallow earthquakes were more prominent than intermediate and deep earthquakes in all thetrenches. The seismic events in the trenches are mostly of magnitude range 3.0-4.9. This magnitude range may indi- cate the genesis of mild to moderate tsunamis in the trench zone in near future once sufficient slip would occur with displacement of water column.

关键词： Focal depth Magnitude Earthquakeoceanic trenche

Screening of Several Anti-Infectives for in Vitro Activity against Mycobacterium smegmatis

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Advances in microbiology 2014年第16期4卷 1197-1203页

作者： Grace Lovia Allotey-Babington Henry Nettey Philip Debrah ofosua Adi-Dako Clement Sasu Anastasia Antwi Yvonne Darko Newriza Nartey Jida asare University of Ghana School of Pharmacy Legon Ghana Mercer University School of Pharmacy Atlanta GA USA

Aim: To evaluate in vitro the effectiveness of several anti-infective agents alone or in combination against Mycobacterium smegmatis. Method: A convenient stratified sampling method was used to obtain selected anti-infective agents. For individual drug samples, Minimum Inhibitory Concentrations (mic) were obtained using the agar-well plate diffusion technique. Fractional Inhibitory Concentration Indices (FICI) were calculated for drug combinations using their mic as obtained from the broth dilution method. Results: of the thirty (30) anti-infective agents analyzed, ten (10) had mic equivalent to or better than rifampicin (reference TB drug). Seven (7) drugs had mic higher than rifampicin, while twelve (12) showed no growth inhibition of M. smegmatis. Analysis of the effect of drug combinations on M. smegmatis indicated that four (4) combinations, including rifampicin/ethambutol showed synergism. one (1) was additive, two (2) were indifferent and one (1) combination showed antagonism. Conclusion: Notable in the results obtained was the high effectiveness of the carbapenems in inhibiting the growth of M. smegmatis. Carbapenems, though not indicated for TB treatment, has a potential of playing a significant role in the treatment of tuberculosis. Also the drug combinations which showed synergism, especially those that involved the macrolide antibiotics, should further be investigated. These results have to be confirmed by in vivo clinical studies to define their roles in tuberculosis treatment.

关键词： Antimicrobials Minimum Inhibitory Concentration M. smegmatis Tuberculosis

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晶状体随年龄变化光学功能减退

世界核心医学期刊文摘(眼科学分册) 2006年第3期 59-60页

作者： Alióo J.L Schimchak P Negri H.P Montés-micóR. 潘佳鸿 VISSUM Instituto Oftalmológico de Alicante Edificio VISSUM Avda. Denia s/n 03016 Alicante SpainDr.

Purpose: To evaluate the optical and densitometric changes that take place in the crystalline lens with aging. Design: Crosssectional study. Participants: Seventy-two eyes of 72 patients of different ages (8-80 years) with a clear lens, a visual acuity of 20/25 or better, and no ocular disease. Methods: In each case, the lens thickness, optical density, modulation transfer function (MTF), and intraocular aberrations were measured. Main outcome Measures: Embryonic and fetal nucleus density, lens thickness, intraocular high-order aberration (HoA), and 0.1 MTF. Results: Embryonic, anterior, and posterior fetal nucleus densities show a positive correlation with age (P o shows a positive correlation with age (Potal ocular and corneal HoAs for a 6-mm pupil show a positive correlation with age (P=0.036 and Pocular and corneal Zernike polynomials Z4i+Zi6 and intraocular spherical aberration (Z04) also show a positive correlation with age (P=0.001, P=0.039, and P=0.001, respectively). Intraocular coma aberration (Z-13) shows a negative linear correlation with age (Pon, 0.1 MTF decreased with age from 18.557 to 10.100 cycles per degree. Conclusion: There is a degradation of the optical quality of the crystalline lens with aging that is associated with morphological changes (thickness and density). These results are important for the consideration of lens replacement in the absence of evident cataract.

关键词：晶状体功能胎儿核胚胎核年龄变化光学

Macrophage inhibitory cytokine-1/growth differentiation factor-15 in premalignant and neoplastic tumours in a high-risk pancreatic cancer cohort

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World Journal of Gastroenterology 2020年第14期26卷 1660-1673页

作者： Robert Sean o’Neill Sam Emmanuel David Williams Alina Stoita Department of Gastroenterology St Vincent’s HospitalSydney 2010Australia St Vincent’s Clinical School Faculty of MedicineUniversity of New South WalesSydney 2010Australia

BACKGRoUND Pancreatic cancer(PC)is a leading cause of cancer related mortality worldwide,with poor survival due to late ***,biomarkers have limited use in early diagnosis of *** inhibitory cytokine-1 or growth differentiation factor-15(mic-1/GDF15)has been implicated as a potential serum biomarker in PC and other *** To determine the role of mic-1/GDF15 in detecting pre-malignant pancreatic lesions and neoplastic tumours in an asymptomatic high-risk cohort part of Australian Pancreatic Cancer Screening *** A feasibility prospective single centre cohort study was *** recruited for yearly surveillance with endoscopic ultrasound(EUS)had serial fasting blood samples collected before EUS for mic-1/GDF15,C-reactive protein and carbohydrate antigen *** were stratified into five groups based on EUS findings:Normal;pancreatic cysts,branch-duct intraductal papillary mucinous neoplasm;diffuse non-specific abnormalities;and neoplastic ***-1/GDF15 serum levels were quantified using *** in whom EUS demonstrated abnormalities but not malignancy were closely followed up with magnetic resonance imaging(MRI)or computed *** one hundred twenty participants were prospectively recruited from ***-seven participants(39.2%)had an abnormal EUS and five participants(4.2%)were diagnosed with neoplastic tumours,three by EUS(two pancreatic and one liver)and two by MRI/computed tomography(breast cancer,bladder cancer),which were performed for follow up of abnormal *** serum mic-1/GDF15 was a significant predictor of neoplastic tumours on receiver operator characteristic curve analysis[area under curve(AUC)=0.814,P=0.023].Baseline serum mic-1/GDF15 had moderate predictive capacity for branch-duct intraductal papillary mucinous neoplasm(AUC=0.644)and neoplastic tumours noted on EUS(AUC=0.793),however this was not significant(P=0.188 and 0.081 respectively).Seria

关键词： Growth differentiation factor 15 Cytokines Pancreatic neoplasms Digestive system neoplasms Pancreatic diseases Biomarkers Diagnostic screening programs