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Spherical Near-Field - Far-Field Transformation for Quasi-Planar Antennas from Irregularly Spaced Data

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Journal of Electromagnetic Analysis and Applications 2012年第4期4卷 147-155页

作者： Francesco D’ agostino Flaminio Ferrara Claudio Gennarelli Rocco Guerriero Massimo Migliozzi Department of Electronic and Computer Engineering University of Salerno Fisciano Italy

An effective near-field - far-field (NF - FF) transformation with spherical scanning for quasi-planar antennas from irregularly spaced data is developed in this paper. Two efficient approaches for evaluating the regularly spaced spherical samples from the nonuniformly distributed ones are proposed and numerically compared. Both the approaches rely on a nonredundant sampling representation of the voltage measured by the probe, based on an oblate ellipsoidal modelling of the antenna under test. The former employs the singular value decomposition method to reconstruct the NF data at the points fixed by the nonredundant sampling representation and can be applied when the irregularly acquired samples lie on nonuniform parallels. The latter is based on an iterative technique and can be used also when such a hypothesis does not hold, but requires the existence of a biunique correspondence between the uniform and nonuniform samples, associ- ating at each uniform sampling point the nearest irregular one. Once the regularly spaced spherical samples have been recovered, the NF data needed by a probe compensated NF - FF transformation with spherical scanning are efficiently evaluated by using an optimal sampling interpolation algorithm. It is so possible to accurately compensate known posi- tioning errors in the NF - FF transformation with spherical scanning for quasi-planar antennas. Some numerical tests assessing the accuracy and the robustness of the proposed approaches are reported.

关键词： Antenna Measurements Near-Field - Far-Field Transformations Spherical Scanning Nonredundant Sampling Representations of Electromagnetic Fields Probe Positioning Errors Compensation

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清初辽东招民授官例实施情况与存疑

兰台世界 2017年第15期 100-104页

作者： SEPE agostino 那不勒斯东方大学意大利那不勒斯80134

顺治十年,清朝统治者为了充实辽沈区域人口,开垦废弃荒地而出台了名为"招民授官例"的鼓励政策,规定将一百人以上招至此地即授予知县官职。然而关于条例的实施,在辽沈地区的史料中唯有一处记载。而其他一些非此地区相关文献,如《大清会典... 详细信息

顺治十年,清朝统治者为了充实辽沈区域人口,开垦废弃荒地而出台了名为"招民授官例"的鼓励政策,规定将一百人以上招至此地即授予知县官职。然而关于条例的实施,在辽沈地区的史料中唯有一处记载。而其他一些非此地区相关文献,如《大清会典》,关内各省地方志书等,则提供了有关辽沈地区各县知县来历与仕途的许多线索。在总结这些史料中的信息后,可分析出授官例的实际实施情况,并对其实施的规律性与严格性提出质疑。

关键词：辽沈地区招民授官知县

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空化诱导轮内流动不稳定性的最大似然估

风机技术 2020年第6期62卷 7-17页

作者： Luca d'agostino Department of Civil&Industrial Engineering Pisa University8 Via Gerolamo Caruso

The article illustrates the application of Bayesian estimation to the identification of flow instabilities,with special reference to rotating cavitation,in a three-bladed axial inducer using the unsteady pressure readings of a single transducer mounted on the casing just behind the leading edges of the impeller *** typical trapezoidal pressure distribution in the blade channels is parametrized and modulated in time and space for theoretically reproducing the expected pressure generated by known forms of cavitation instabilities(cavitation auto-oscillations and higher-order surge cavitation modes,n-lobed subsynchronous/synchronous/super-synchronous rotating cavitation).The Fourier spectra of the theoretical pressure so obtained in the rotating frame are transformed in the stationary frame,frequency broadened to better approximate the experimental results,and parametrically fitted by maximum likelihood estimation to the measured auto-correlation *** form of instability generates a characteristic distribution of sidebands in addition to its fundamental *** identification makes use of this information for effective detection and characterization of multiple simultaneous flow instabilities with intensities spanning over about 20 db down to about 4 db signal-to-noise *** same information also allows for effectively bypassing the aliasing limitations of traditional cross-correlation methods in the discrimination of multiple-lobed azimuthal instabilities from the measurements returned by arrays of equally spaced *** method returns both the estimates of the model parameters and their standard deviations,providing the information needed for the assessment of the statistical significance of the *** proposed approach represents therefore a promising tool for experimental research on flow instabilities in high-performance turbopumps.

关键词： Rocket Propulsion Liquid Propellant Rocket Engines Turbomachinery Turbopumps Turbopump Cavitation Instabilities Parametric Identification

火箭发动机导流器和涡轮泵中空化不稳定性和转子动力学载荷（英文）

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风机技术 2018年第3期60卷 45-61页

作者： Luca d’agostino Civil and Industrial Engineering Department University of Pisa

After a brief review of flow-induced instabilities in turbopumps for liquid propellant feed systems of modern rocket engines, some recent results of the work carried out by the author and his collaborators to elucidate the role of cavitation on the development of unsteady flow phenomena and rotordynamic impeller forces in these machines are illustrated. Specifically, the results are presented of a series of tests conducted in water in the Cavitating Pump Rotordynamic Test Facility(CPRTF) under similarity conditions on a threebladed, tapered-hub, high-head *** flow instabilities detected in these machines include axial cavitation surge oscillations, backflow oscillations, non-synchronous and synchronous(alternating blade) rotating cavitation, higher-order surge and higher-order rotating cavitation, depending on the operational conditions of the machine. The occurrence of these instabilities under the relevant operational conditions is critically *** characterization of the rotordynamic forces acting on the whirling impellers of the above machines under different load and cavitation conditions is also illustrated and discussed. The results have been obtained in the CPRTF by means of a novel experimental technique that allows for the continuous measurement of the rotordynamic force spectra as functions of the whirl ratio. Comparison with simultaneous high-speed movies of the inducer inlet flow highlights the relationship between the cavitation dynamics in the inducer backflow and the spectral behavior of the rotordynamic force as functions of the whirl ratio.

关键词： Turbomachines Turbopumps Aerospace Propulsion Rocket Propulsion Liquid Propellant Rocket Engines Liquid Propellant Feed Turbopumps Two-Phase Flows Cavitation Inducers Unsteady Turbopump and Inducer Hydrodynamics Flow Instabilities Rotordynamics Rotordynamic Fluid Forces Cavitation-Induced Flow Instabilities

Repeat liver surgery by laparoscopy for a malignant recurrence after previous open or laparoscopic resection

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Hepatoma Research 2015年第1期1卷 30-35页

作者： Luigi Cioffi Andrea Belli Corrado Fantini Alberto D’agostino Gianluca Russo Giulio Belli Department of General and Hepato-Pancreato-Biliary Surgery Loreto Nuovo Hospital80142 NaplesItaly Department of Abdominal Oncology Division of Surgical OncologyIstituto Nazionale Tumori Fondazione G.Pascale-IRCCS80131 NaplesItaly

Aim:This paper reported the experience of one center on repeat laparoscopic liver surgery for metastasis and hepatocellular carcinoma(HCC)with a review of the ***:This retrospective study included 24 patients who underwent laparoscopic re-intervention(hepatic resection and radiofrequency ablation)for recurrent HCC in cirrhosis(n=17)and for recurrent malignant metastases(n=7)after a previous open or laparoscopic *** were divided into two groups according to the fi rst surgical *** 1 underwent open resection and laparoscopic procedure(7 patients),and Group 2 underwent laparoscopic resection and laparoscopic procedure(17 patients).Results:Mean operative time for re-intervention was signifi cantly longer for Group 1(220.14±80.06 min)than for Group 2(150±56.18 min;P=0.001),whereas the mean blood loss and mean hospital stay were comparable in both *** to Dindo-Clavien classifi cation,overall morbidity ranged between Grade I and IIIa and was similar in both ***:This study suggests that repeat laparoscopic surgery for recurrent hepatic malignant diseases in selected patients is a feasible and safe procedure with good short-term outcomes,but further prospective studies are needed to support these results.

关键词： Recurrence repeat liver surgery resection

CD44v8-10 is a marker for malignant traits and a potential driver of bone metastasis in a subpopulation of prostate cancer cells

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Cancer Biology & Medicine 2021年第3期18卷 788-807页

作者： Rosaria A.Fontanella Silvia Sideri Chiara Di Stefano Angiolina Catizone Silvia Di agostino Daniela F.Angelini Gisella Guerrera Luca Battistini Giulia Battafarano Andrea Del Fattore Antonio Francesco Campese Fabrizio Padula Paola De Cesaris Antonio Filippini Anna Riccioli Department of Anatomy HistologyForensic Medicine and OrthopaedicsUnit of Histology and Medical EmbryologySapienza UniversityRome 00161Italy Department of Health Sciences School of Medicine-"Magna Graecia"University of Catanzaro Catanzaro 88100Italy IRCCS Fondazione Santa Lucia Rome 00143 Bone Physiopathology Research Unit Genetics and Rare Diseases Research DivisionBambino GesùChildren’s HospitalIRCCSRome 00146Italy Department of Molecular Medicine Sapienza UniversityRome 00161Italy Department of Life Health and Environmental SciencesUniversity of L’AquilaL'Aquila 67100Italy

Objective:Bone metastasis is a clinically important outcome of prostate carcinoma(PC).We focused on the phenotypic and functional characterization of a particularly aggressive phenotype within the androgen-independent bone metastasis-derived PC3 cell *** cells,originated from the spontaneous conversion of a CD44-negative subpopulation,stably express the CD44 v8-10 isoform(CD44 v8-10 pos)and display stem cell-like features and a marked invasive phenotype in vitro that is lost upon CD44 v8-10 ***:Flow cytometry,enzyme-linked immunoassay,immunofluorescence,and Western blot were used for phenotypic and immunologic ***-time quantitative polymerase chain reaction and functional assays were used to assess ***:Analysis of epithelial–mesenchymal transition markers showed that CD44 v8-10 pos PC3 cells surprisingly display epithelial phenotype and can undergo osteomimicry,acquiring bone cell phenotypic and behavioral *** of specific si RNA evidenced the ability of CD44 v8-10 variant to confer osteomimetic features,hence the potential to form bone-specific ***,the ability of tumors to activate immunosuppressive mechanisms which counteract effective immune responses is a sign of the aggressiveness of a *** we report that CD44 v8-10 pos cells express programmed death ligand 1,a negative regulator of anticancer immunity,and secrete exceptionally high amounts of interleukin-6,favoring osteoclastogenesis and immunosuppression in bone ***,we identified a novel pathway activated by CD44 v8-10,involving tafazzin(TAZ)and likely the Wnt/TAZ axis,known to play a role in upregulating osteomimetic ***:CD44 v8-10 could represent a marker of a more aggressive bone metastatic PC population exerting a driver role in osteomimicry in bone.A novel link between TAZ and CD44 v8-10 is also shown.

关键词： Metastasis epithelial phenotype EMT MET IL-6 TAZ

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混流空间诱导轮的性能快速交互设计（英文）

风机技术 2019年第3期61卷 1-13,I0006页

作者： Luca d’agostino Civil and Industrial Engineering Department University of Pisa

本文介绍了一种空间推进用混流锥形轮毂诱导轮初步设计和空化性能预测降阶模型的开发与实验验证。该模型通过将二维轴向涡度修正施加到充分导向轴对称流(其轴向速度沿径向均匀分布)上,来描述叶片流道中的三维不可压缩、无粘性、无旋流... 详细信息

本文介绍了一种空间推进用混流锥形轮毂诱导轮初步设计和空化性能预测降阶模型的开发与实验验证。该模型通过将二维轴向涡度修正施加到充分导向轴对称流(其轴向速度沿径向均匀分布)上,来描述叶片流道中的三维不可压缩、无粘性、无旋流动。在不忽略径向流动的情况下适当地再定义了叶片的扩压系数,可以控制叶片的负载,并在设计流量系数下预估边界层阻塞和叶片粘性损失,为匹配轮毂型线与叶距角的轴向变化提供一个简单的判据。采用卡特法则计算诱导轮尾缘处的流量偏差。利用质量守恒定律、角动量守恒定律和欧拉方程,推导出了一个简化的二阶边值问题,其数值解定义了诱导轮出口的远场轴对称流速。对攻角、机匣和叶顶间隙损失进行适当的半经验修正,进而得到空化性能。该模型已被证实与在空化泵转子动力学试验装置中测试的两个空间诱导轮的几何和空化特性十分接近,与文献中提到的许多锥形轮毂诱导轮也十分相似。

关键词：交互设计性能预测诱导轮流空间角动量守恒定律叶片流道降阶模型轴向速度

Quality of Soppressata salami from Pugliese Pigs as Affected by Rearing System

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Food and Nutrition Sciences 2014年第7期5卷 626-634页

作者： Marzia Albenzio Antonella Santillo Rosaria Marino Francesca d’ Angelo Mariangela Caroprese agostino Sevi Department of the Sciences of Agriculture Food and Environment University of Foggia Foggia Italy

Twenty four male pigs were assigned to two groups of 12 each during the last fattening phase: one group was reared outdoor (OUT group) and fed on natural pasture, while the other group was reared indoor (IND group) and fed on commercial feedstuff. Meat was processed into Soppressata salami according to traditional protocol. Meat and Soppressata salami were analyzed for nutritional, textural and color parameters. Meat and Soppressata salami showed significantly higher proportion of unsaturated fatty acids in OUT than that in IND group. Ameliorated nutritional indexes in terms of n-6/n-3 ratio, and thrombogenic index were found both in meat and Soppressata salami in OUT group. Texture Profile Analysis showed lower values in the tested samples from OUT thanINDgroup. Lightness, redness, and chroma parameters were higher both in meat and Soppressata salami in OUT group;whereas hue parameter was lower in Soppressata salami from OUT pigs. Outdoor rearing improved fatty acid profile, nutritional indexes, color and mechanical properties of pork meat thanks to natural pasture, greater space allowance and physical exercise of animal during the fattening phase. Meat features strictly affected the quality of the Soppressata salami produced by using traditional protocol.

关键词： Pig Meat Soppressata salami Nutritional Properties Textural Properties Meat Color

Impaired gallbladder motility and delayed orocecal transit contribute to pigment gallstone and biliary sludge formation in β-thalassemia major adults

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World Journal of Gastroenterology 2004年第16期10卷 2383-2390页

作者： PieroPortincasa AntonioMoschetta MassimoBerardino agostino Di Ciaula Michele Vacca Giuseppe Baldassarre AnnaPietrapertosa RosarioCammarota NunziaTannoia Giuseppe Palasciano Section of Internal Medicine Department of Internal Medicine and Public Medicine (DIMIMP)University Medical SchoolBariItaly Division of Internal Medicine Hospital of BisceglieItaly Division Chair

AIM: Gallbladder and gastrointestinal motility defects exist in gallstones patients and to a lesser extent in pigment gallstone patients. To investigated the role of gallbladder and gastrointestinal motility disorders in pigment gallstoneformation in β-thalassemia ***: Twenty-three patients with β-thalassemia major (16 females; age range 18-37 years) and 70 controls (47 females, age range 18-40 years) were studied for gallbladder and gastric emptying (functional ultrasonography),orocecal transit (OCTT, H2-breath test), autonomic dysfunction (sweat-spot, cardiorespiratory reflex tests),bowel habits, gastrointestinal symptoms and quality of life (all with questionnaires). Gallbladder content (ultrasonography) was examined before and during 8-12 mo ***: Gallstones and/or biliary sludge were found in 13 (56%) patients. β-thalassemia major patients had increased fasting (38.04-4.8 mL vs 20.3±0.7 mL, P= 0.0001) and residual (7.94-1.3 mL vs 5.1±0.3 mL, P= 0.002) volumeb and slightly slower emptying (24.94±2.7 min vs20.2±0.7 min,P = 0.04) of the gallbladder, together with longer OCTT(232.24±7.8 rain vs99.7±2.3 rain, P= 0.00003) than *** differences in gastric emptying and bowel habits were found. Also, patients had higher dyspepsia (score: 6.74-1.2vs 4.94-0.2, P = 0.027), greater appetite (P = 0.000004) and lower health perception (P = 0.00002) than *** dysfunction was diagnosed in 52% of patients (positive tests: 76.2% and 66.7% for parasympathetic and sympathetic involvement, respectively). Patients developing sludge during follow-up (38%, 2 with prior stones) had increased fasting and residual gallbladder ***: Adult β-thalassemia major patients have gallbladder dysmotility associated with delayed small intestinal transit and autonomic dysfunction. These abnormalities apparently contribute together with haemolytic hyperbilirubinemia to the pathogenesis of pigment gallstones/sludge in β-thalassemia major.

关键词：胆囊运动性转接色素胆石症胆汁淤积 β-地中海贫血症成年人胃肠运动