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Background: Hypertrophic cardiomyopathy (HCM) is a common cardiac genetic disorder that clinically manifests with sudden death and progressive heart failure. Moreover, thyroid dysfunction is associated with increased cardiovascular morbidity and mortality risks. Therefore, this study aimed to clarify whether thyroid hormones could serve as an independent predictor of adverse events in patients with HCM. Methods: The cohort consisted of 782 patients with HCM who had thyroid hormones baseline data and were admitted to the Affiliated Hospital of Jiaxing University. Patients were divided into two groups according to serum levels of free triiodothyronine (fT3): the normal fT3 and low triiodothyronine (T3) syndrome groups. Low T3 syndrome was defined as fT3 < 2.43 pmol/L with a normal thyroid‐stimulating hormone (TSH) level. Patients whose TSH levels were abnormally high or abnormally low were excluded from this study. The primary endpoint was the occurrence of sudden cardiac death (SCD) events, and the secondary endpoint was a composite of worsening heart failure (WHF) events, including heart failure death, cardiac decompensation, hospitalization for heart failure, and HCM‐related stroke. The Kaplan–Meier and Cox regression were performed for the survival analysis. Results: After a median follow‐up of 52 months, 75 SCD events and 134 WHF events were recorded. The Kaplan–Meier survival curves showed that the cumulative incidence of SCD events and WHF events were significantly higher in patients with low T3 syndrome (log‐rank p =.02 and log‐rank p =.001, respectively). Furthermore, multivariate Cox regression analysis demonstrated that low T3 syndrome is a strong predictor of SCD events and WHF events (adjusted hazard ratio [HR: 1.53, 95% confidence interval [CI]: 1.13–2.24, p <.01; HR: 3.87, 95% CI: 2.91–4.98, p <.001, respectively). Conclusions: Low T3 syndrome is highly prevalent among patients with HCM and was independently associated with an increased risk of SCD events and WHF events. The routine assessment of serum fT3 levels may provide risk stratification in this population. [ABSTRACT FROM AUTHOR]

The East Kunlun Orogen (EKO) is located in the western part of China and has witnessed the Late Permian–Triassic tectonic evolution involving the A'nyemaqen Ocean (a part of the Palaeo‐Tethys Ocean). In this study, geochronology, geochemistry, and Hf isotope analysis of Late Permian–Triassic granitoids were carried out. Zircon U–Pb dating of Dachagou granodiorite and monzogranite in the western part of the EKO (W–EKO) is 233.4 ± 1.1 and 225.8 ± 1.2 Ma, respectively. The Dachagou granodiorite and monzogranite are characterized by low values of 10, 000 Ga/Al ratios (1.75–2.06, 1.42–1.60) similar to those of I‐type granite. The εHf (t) (−2.4 to +0.1, −3.0 to +0.2) indicate that the magma forming these granites was derived from a mafic Mesoproterozoic lower crust. Zircon U–Pb age of Lalingzaohuo quartz diorite is 244.5 ± 2.6 Ma, and its εHf(t) values (−0.7 to +2.5) indicate the origin of crust–mantle mixing. Zircon U–Pb ages for Nagengkangqieer granodiorite and monzogranite in the eastern part of the EKO (E–EKO) are 250.1 ± 2.8 and 238.9 ± 2.2 Ma, respectively. These rocks are also characterized by low 10, 000 Ga/Al ratios (2.37–2.66 and 2.49–2.63) again similar to I‐type granite. The εHf(t) (−3.9 to 0.4, −3.3 to 1.1) indicate that the magma was derived from the crustal materials. As contemporaneous rocks, the Dachagou and Nagengkangqieer granodiorites and the Lalingzaohuo quartz diorites are formed in a subduction environment. However, the Dachagou and Nagengkangqieer monzogranites are formed in a collision environment. Based on this result, the closure time of the W–EKO and E–EKO of the A'nyemaqen Ocean had an age gap of ~15 Ma, hence the closure mode of the A'nyemaqen Ocean should be a "scissor‐type" closure. [ABSTRACT FROM AUTHOR]

Chemotherapy is an effective approach for cancer therapy when plant‐derived sensitizers are combined with chemotherapeutics. Zerumbone, a natural phytochemical, has been documented to have various pharmacological roles. Here, we evaluated the chemosensitization potential of zerumbone in a breast cancer cell line in vitro. Zerumbone‐induced cytotoxicity in MCF‐7 cells was assessed by 3‐[4,5‐dimethylthiazole‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT)‐based metabolic analysis. Reactive oxygen species (ROS)‐mediated mitochondrial membrane alterations, DNA damage, and apoptotic morphological changes were measured by fluorescence microscopy methods. A biochemical assay was employed to analyze Thiobarbituric acid reactive substances (TBARS) and antioxidant levels. Apoptotic marker expression levels were investigated by immunoblotting. MTT assay revealed that zerumbone significantly enhanced paclitaxel (PTX)‐induced cell death in breast cancer cells in a concentration‐dependent manner. Furthermore, our study demonstrated that zerumbone (15 μM) significantly enhanced ROS when combined with PTX (1 μM) treatment. Additionally, we observed that zerumbone enhanced the impairment of mitochondrial membrane potential and oxidative DNA damage, thereby inducing apoptosis in combination with PTX. Western blot analysis indicated that zerumbone significantly upregulated BAX, caspase‐7, and caspase‐9 expression and decreased BCL‐2 expression, thereby inducing proapoptotic protein‐mediated cell death combined with PTX. The prooxidant properties of zerumbone potentially resensitize breast cancer cells to PTX by enhancing intracellular ROS‐mediated oxidative stress. [ABSTRACT FROM AUTHOR]

The Hongqiling‐Piaohechuan region in the east Central Asian Orogenic Belt (CAOB) is an economically important Ni–Cu sulphide mineralization region in China. It is widely accepted that these Ni–Cu sulphide deposits mainly formed during the Late Triassic period. The early Middle Triassic mafic‐ultramafic plutons are therefore key in understanding the mineralization process. Here, we report the laser ablation inductively coupled plasma mass spectrometer (LA‐ICP‐MS) U–Pb dating of zircon and geochemical data for two Middle Triassic mafic‐ultramafic plutons and one felsic pluton in central and eastern Jilin Province, NE China. The mafic‐ultramafic plutons are composed of gabbronorite and olivine websterite. Zircon dating results indicate that these mafic‐ultramafic plutons crystallized at 243 ± 1 to 245 ± 1 Ma in the Middle Triassic. The coeval felsic pluton is mainly quartz diorite. Zircon dating results indicate that the felsic pluton crystallized at 239.7 ± 0.63 Ma in the later period of Middle Triassic. The mafic‐ultramafic plutons are low in SiO2 (43.49–49.66 wt%), depleted in K2O (0.28–2.74 wt%) and Na2O (0.70–1.18 wt%). They have low rare earth element (REE) abundances without Eu anomalies, exhibit depletion in high‐field‐strength elements (HFSEs), and hold various εHf(t) values (−15.3 to +2.9). These findings suggest that the primary magma of mafic‐ultramafic plutons was derived from the partial melting of the depleted lithospheric mantle, metasomatized by subducted‐slab‐derived fluids/melts. Remarkably, these mafic‐ultramafic plutons have extremely high Cu–Ni contents (23.6–669.4 and 419–1,956 ppm, respectively). The coeval quartz diorites have 59.55–64.86 wt% of SiO2, 3.02–4.21 wt% of K2O and 3.97–4.49 wt% of Na2O. They are enriched in light REEs (LREEs) and large‐ion lithophile elements (LILEs); depleted in heavy REEs (HREEs) and HFSEs, and they have εHf(t) values in the range −6.4 to +2.9. Additionally, the felsic rocks exhibit adakitic‐features with high Sr/Y (28.5–58.7) and (La/Yb)N (4.9–12.2) ratios, implying the thickening crustal sources of the North China Craton (NCC) and CAOB, respectively. The above findings, combined with the regional geological data, suggest that the Middle Triassic mafic‐ultramafic plutons are the prelude to the large‐scale Late Triassic mineralization. This was induced by the thickening event of the later period of Middle Triassic felsic rocks, accompanying the final closure of the Palaeo‐Asian Ocean (PAO) in the eastern CAOB. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of robust H8 control for uncertain impulsive systems with input constraints. The parametric uncertainties are assumed to be time-varying and norm-bounded. The input constraints under consideration are novel reverse polytopic constraints avoiding a set of specified input values. Via the designed state feedback switching control law, the input constraints can be satisfied. Moreover, by applying the Lyapunov function theory, sufficient conditions for robust stabilization and H8 control are established in terms of linear matrix inequalities. A numerical example is given to demonstrate the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

Nonrecurrent geomagnetic storms caused by Coronal Mass Ejection (CME) can induce serious impacts on space- and ground-based equipment. However, these nonrecurrent geomagnetic storms are hard to predict since CMEs are not periodic. Previous studies have shown that the variations of Cosmic Ray Intensity (CRI) before nonrecurrent storms may forebode the coming geomagnetic storm. But it is difficult to extract the variations since the cosmic ray flux is a complex signal. In order to identify the precursory signal in CRI variations triggered by CME, an ensemble self-adaptive time-frequency analysis method was proposed and applied to 65 nonrecurrent geomagnetic storms occurred between 1998 and 2019. The results indicate that the precursory signals are successfully identified in 43 of 45 storms, after excluding 20 storms accompanied by ground level enhancement. In addition, it is also found that the spectral density of the precursory signal could reflect the active level of geomagnetic condition, which is lower during geomagnetic quiet period. [ABSTRACT FROM AUTHOR]

The Chaqiabeishan area of the Quanji Massif in NW China is characterized by extensive Li‐rich pegmatites and granites of various ages. In this study, the major and trace element compositions, U–Pb zircon ages, and zircon Hf isotopic compositions of the granites were investigated, including the Garideng porphyritic monzogranite, the Gongkaxiuma monzogranite, and the Narong granitic porphyry. Precise U–Pb zircon dating revealed that these three granites were emplaced at approximately 468, 444, and 245 Ma, respectively. The geologic and geochemical data indicate that the Garideng porphyritic monzogranite and the Narong granitic porphyry are two I‐type granites, and the Gongkaxiuma monzogranite is an A2‐type granite. Based on the Hf isotopes and geochemical data, the Garideng porphyritic monzogranite and the Narong granitic porphyry were derived from partial melting of the relatively deep and relatively shallow juvenile mantle‐derived mafic lower crust, respectively, while the Gongkaxiuma monzogranite was derived from partial melting of the granulitic metamorphic basement. Moreover, tectonically, the Garideng porphyritic monzogranite represents the northward subduction of the South Qilian oceanic plate from 500 to 440 Ma. The Gongkaxiuma monzogranite represents the closure of the South Qilian Ocean by ~440 Ma, and the Narong granitic porphyry represents the Late Permian to Middle Triassic southward subduction of the Zongwulong oceanic plate under the Quanji Massif. [ABSTRACT FROM AUTHOR]

Background: G protein‐coupled receptor 12 (GPR12) is an orphan receptor with no confirmed endogenous ligands. It plays important roles in both physiological and pathological conditions such as neurogenesis and neural inflammation. However, it remains unclear whether GPR12 regulates carcinogenesis and progression in head and neck squamous cell carcinoma (HNSCC), such as esophageal cancer (EC) and hypopharyngeal cancer (HC). Methods: The Cancer Genome Atlas (TCGA) database was applied to explore the expression of GPR12. Quantitative real‐time polymerase chain reaction (qRT‐PCR) was used to detect the expression of GPR12 in cancer tissues. Wound healing and transwell assays were carried out to verify the effect of GPR12 on cell migration. Flow cytometric analysis and caspase‐Glo 3/7 assay were carried out to verify the influence of GPR12 on cell apoptosis. Western blotting was used to measure the expression of proteins related to migration and apoptosis. Result: The qRT‐PCR analyses showed that the expression of GPR12 decreased in EC and HC than that in their paired adjacent normal tissues. Wound healing assay and transwell assay demonstrated that GPR12 inhibited tumor cell migration. Flow cytometry analysis and Caspase‐Glo 3/7 Assay suggested that GPR12 promoted apoptosis. The mechanism of GPR12 may function via modulating caspase‐7, E‐cadherin, and α‐catenin in EC and HC cells. Conclusion: In conclusion, GPR12 induced apoptosis by activating caspase‐7 and inhibited migration through epithelial‐to‐mesenchymal transition (EMT) in EC and HC. Our findings demonstrated that GPR12 as a potential tumor suppressor mediated cell migration and apoptosis in EC and HC. [ABSTRACT FROM AUTHOR]

Iron is not only an essential trace element for plant growth and development, but also an indispensable trace element for humans. The objective of this study was to investigate the Fe absorption and utilization, water use efficiency (WUE) and grain yield difference between upland rice (Oryza sativa L.) cultivar Zhonghan 3 (japonica) and paddy rice cultivar Wuxiangjing 99-8 (japonica) which were grown on the farm of the Yangzhou University under three cultivation patterns of continuously flooded condition (CF, control), plastic film mulching cultivation (PFMC), and bare cultivation (BC) under non-flooded conditions. Compared with the CF, the grain yield was significantly lower under the PFMC for upland rice, but no significant difference was found for paddy rice, and grain yield was significantly reduced under BC for both upland rice and paddy rice. Dry cultivation lowered the Fe concentration in the rice plants and grain under the PFMC and the BC, and lowered the amount of Fe absorption in aboveground plants. Whereas, Fe use efficiency and WUE were all higher with dry cultivation. Compared with paddy rice, the Fe concentration in the whole root system of upland rice was 39.5% lower, but that in the roots was 11.3% higher at heading stage, and in the aboveground plants and rice flour was 3.4 to 11.1% higher at heading and maturity stages. The results indicate that dry cultivation is a good water conservation cultivation method in arid and semiarid regions with unstable irrigation sources while temperature is favorable to rice growth, such as in Southeast China. [ABSTRACT FROM AUTHOR]

The deformation of reflector surface can be obtained by Misell algorithm using two far-field amplitude patterns: one with the antenna in focus and the other with the antenna defocused. For reflector antennas with active surface, the defocused pattern can be measured by adjusting the panels to get a more effective phase factor instead of offsetting the sub-reflector. The shape and size of phase factor have a great influence on the accuracy of convergent solution. To improve the performance of Misell algorithm, this study proposed an optimisation method for phase factors under different surface deformations. This method utilises Levenberg-Marquardt algorithm to get an estimation of the aperture distribution and then applies the particle swarm optimisation to optimise the phase factor parameterised by Zernike polynomials. Numerical simulations show that the proposed method is an efficient tool to achieve applicable phase factors under different surface deformations. Using the optimised phase factor, Misell algorithm can get a better convergent performance than traditional Misell algorithm. [ABSTRACT FROM AUTHOR]

Surface diagnosis methods based on phase retrieval algorithm have been successfully applied to many large reflector antennas. In the phase retrieval algorithm, surface distortion is retrieved by multiple far field patterns. The different far field patterns are connected to each other by an important element called 'phase factor'. This study investigates the effect of the phase factor on the phase retrieval algorithm. Generally, the phase factor is simple for the phase retrieval algorithm. In this study, a new method based on the active surface system is proposed to produce more flexible and diverse phase factors. Through digital simulations, the effect of different kinds of phase factors on the phase retrieval algorithm is discussed. In addition, the inaccuracy of the phase factor caused by the mechanism error is considered.. [ABSTRACT FROM AUTHOR]

To improve the measurement accuracy of an absolute imaging position encoder, a novel edge detection method is developed to accurately detect the edges of grating lines based on empirical mode decomposition (EMD). First, according to the characteristics of the absolute position coding image (APCI), the vertical projection of the grey-level APCI is achieved by conventional grey-level transformation. Then, the vertical projection contour is decomposed by an EMD method and a finite number of intrinsic mode functions (IMFs) are achieved. Next, the last two IMFs are used to describe the trend of the projection contour. The trend is used as adaptive thresholds to divide the vertical projection contour into different intervals. Finally, the second derivate of the vertical projection contour is applied to obtain the accurate edges in each interval. Experimental results indicate that the proposed method is more robust to heavy noise, bad illumination and a slope compared with the existing methods with respect to edge detection. Also, the proposed method achieves better measurement accuracy than the existing methods. [ABSTRACT FROM AUTHOR]

In this paper, we present new U-Pb zircon ages, Hf isotope data and major and trace elements for Early Mesozoic granitic rocks in Mohe area in the Erguna Massif of northeast China to elucidate the southward subduction of the eastern Mongol-Okhotsk Oceanic plate in Early Mesozoic. Zircons from two representative intrusions, syenogranites and monzogranites, in the Mohe area are euhedral-subhedral in shape, display oscillatory growth zoning in cathodoluminescence (CL) images, and have Th/U ratios of 0.10-0.72, and in combination these features indicating that the zircons are of igneous origin. U-Pb zircon dating results demonstrate that the syenogranites formed at 245.1 ± 1.4 Ma and monzogranites formed at 212.2 ± 1.7 Ma. These granitic rocks are characterized by high SiO2, Al2O3 and (Na2O + K2O), low TFeO, MgO, TiO2 and P2O5 concentrations, belonging to the high-K calc-alkaline series. They are enriched in LREE and large ion lithophile elements (e.g., Rb, K, and Sr), depleted in HREE and high field strength elements (e.g., Nb, Ta, Th, and Ti), as well as very weak negative Eu anomalies (Eu/Eu* = 0.48 ~ 1.01). Their zircon εHf(t) values range from −7.9 to −2.0 and range from 0.20 to 0.49, in response to their two-stage Hf model ages (TDM2) range from 1.40 Ga to 1.77 Ga range from 0.94 Ga to 1.24 Ga, respectively, indicating that primary magmas of syenogranites were derived from partial melting of newly accreted juvenile crustal material that formed from the enriched mantle during the Mesoproterozoic, monzogranites are generated by partial melting of newly accreted juvenile crustal material that formed from the depleted mantle during the Meso- to Neoproterozoic. We conclude, therefore, that the early Mesozoic granitic rocks of the Mohe area are associated with the continuous southward subduction of the Mongol-Okhotsk oceanic plate rather than the Paleo-Asian and circum-Pacific tectonic regimes. [ABSTRACT FROM AUTHOR]

BACKGROUND Pale, soft and exudative ( PSE) meat is a quality problem that causes a large economic loss to the pork industry. In the present work, near infrared ( NIR) quantification and identification methods were used to investigate the feasibility of differentiating potential PSE meat from normal meat. RESULTS NIR quantification models were developed to estimate meat pH and colour attributes ( L*, a*, b*). Promising results were reported for prediction of muscle pH ( R2CV = 70.10%, RPDCV = 1.83) and L* ( R2CV = 77.18%, RPDCV = 1.91), but it is still hard to promote to practical application at this level. The Factorisation Method applied to NIR spectra could differentiate potential PSE meat from normal meat at 3 h post-mortem. Correlation analysis showed significant relationship between NIR data and LF-NMR T2 components that were indicative of water distribution and mobility in muscle. PSE meat had unconventionally faster energy metabolism than normal meat, which caused greater water mobility. CONCLUSION NIR spectra coupled with the Factorisation Method could be a promising technology to identify potential PSE meat. The difference in the intensity of H2O absorbance peaks between PSE and normal meat might be the basis of this identification method. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this paper we present new zircon U-Pb ages, whole-rock major and trace element analyses, and zircon Hf isotopic data for magmatic rocks in the Tuotuohe region of the western segment of the Jinshajiang suture. Our aim is to constrain the Early Permian-Late Triassic tectonic evolution of the region. Zircons from the magmatic rocks of the Tuotuohe region are euhedral-subhedral in shape and display fine-scale oscillatory zoning as well as high Th/U ratios (0.4-4.6), indicating a magmatic origin. The zircon U-Pb ages obtained using LA-ICP-MS are 281 ± 1 Ma, 258 ± 1 Ma, 244 ± 1 Ma, and 216 ± 1 Ma, which indicate magmatism in the Early Permian-Late Triassic. A diorite from Bashihubei (BSHN) has SiO2= 57.18-59.97 wt%, A12O3= 15.70-16.53 wt%, and total alkalis (Na2O + K2O) = 4.46-6.34 wt%, typical of calc-alkaline and metaluminous series. A gabbro from Bashibadaoban (BSBDB) belongs to the alkaline series, and is poor in SiO2 (45.46-54.03 wt%) but rich in A12O3 (16.19-17.39 wt%) and total alkalis (Na2O + K2O = 5.48-6.26 wt%). The BSHN diorite and the BSBDB gabbro both display an enrichment of LREEs and LILEs and depletion of HFSEs, and they have no obvious Eu anomaly; they have relatively low MgO contents (2.54-4.93 wt%), Mgs# values of 43 to 52, and low Cr and Ni contents (8.07-33.6 ppm and 4.41-14.2 ppm, respectively), indicating they differentiated from primitive mantle magmas. They have low Nb/U, Ta/U, and Ce/Pb ratios (1.3-9.6, 0.2-0.8, and 0.1-18.1, respectively), and their initial Hf isotopic ratios range from +9.6 to +16.9 (BSHN diorite) and +6.5 to +12.6 (BSBDB gabbro), suggesting their primary magmas were derived mainly from the partial melting of a mantle wedge that had been metasomatized by subduction fluids. Taking all the new data together, we conclude that the western and eastern segment of the Jinshajiang suture regions underwent identical processes of evolution in the Early Permian-Late Triassic: oceanic crust subduction before the Early Permian, continental collision during the Early-Middle Triassic, and post-collisional extension from the Late Triassic. [ABSTRACT FROM AUTHOR]

The Hongtoushan copper-zinc deposit is the only large Archean volcanogenic massive sulfide ( VMS) deposit in China. This paper presents new information on the timing of metallogenesis and metamorphism of the deposit, including new cathodoluminescence ( CL) images, and Th U−1 and LA- ICP- MS U- Pb dating on zircons of the biotite-plagioclase gneiss and plagioclase-amphibole gneiss that host the deposit. The CL images and Th U−1 ratios indicate that the zircons within the gneiss are of metamorphic origin. LA- ICP- MS dating of the plagioclase-amphibole gneiss yielded the upper intercept ages of 2549 Ma, and the biotite-plagioclase gneiss yielded the upper intercept ages of 2552 Ma and 2550 Ma correspondingly, indicating that the mineralization of the deposit occurred at around 2550 Ma. The rims of zircons within these host rocks yielded younger U- Pb ages at 2529, 2520 and 2515 Ma, identical to the age of felsic intrusive rocks in the study area. This suggests that the Hongtoushan VMS deposit underwent initial metamorphism and deformation at around 2520 Ma by the intrusion of granite magmas. [ABSTRACT FROM AUTHOR]

The CO2 sorption/desorption kinetic behaviors on Li4SiO4 were analyzed. The theoretical compositions of the sorption/desorption reactions were calculated using FactSage. The sorption/desorption process on Li4SiO4 was investigated by comparing the shrinking core, double exponential, and Avrami-Erofeev models. The Avrami-Erofeev model fits the kinetic thermogravimetric experimental data well and, together with the double-shell mechanism, clearly explains the sorption/desorption mechanism. The sorption process is limited by the rate of the formation and growth of the crystals with double-shell structure consisting of Li2CO3 and Li2SiO3. The whole desorption process is found to be controlled by the rate of the formation and growth of the Li4SiO4 crystals. Furthermore, the influence of steam on the CO2 sorption process was analyzed. It has been observed that the presence of steam enhance the mobility of Li+ and, therefore, the rate of diffusion control stage. © 2012 American Institute of Chemical Engineers AIChE J, 59: 901-911, 2013 [ABSTRACT FROM AUTHOR]

The Misell algorithm is an effective phase-retrieval holography method for measuring the surface error of large reflector antennas. However, it is investigated experimentally to have a low accuracy at low signal-tonoise ratio (SNR). To decrease the great sensitivity to noise of Misell algorithm, a new iterative Fourier filtering approach based on autocorrelation theorem is proposed. The iterative Fourier filtering approach is used to remove some of the imperfection present in far-field amplitude data. The computer simulation results of Shanghai Sheshan-25m-telescope model show that the proposed approach improved the accuracy of Misell algorithm at low SNR obviously. [ABSTRACT FROM AUTHOR]

Although the majority of the existing robust adaptive beamformers focus on how to choose an identical loading factor for all eigenvalues, relatively few investigations on variable loading (VL) have been conducted. A low-complexity VL beamformer is proposed in which the beamformer weight vector is deliberately prevented from converging to the noise components. Then inspired by the traditional identical loading method, the loading factor can be set in an ad hoc manner. Numerical results demonstrate the superior performance of the proposed beamformer relative to other existing approaches such as 'identical diagonal loading' and 'robust Capon' beamformers. [ABSTRACT FROM AUTHOR]

Microwave holographic techniques have been used widely in the radio astronomy area. A new surface diagnosis method based on the phaseretrieval holograph algorithm is proposed. This approach focuses on a novel application of the active deformation. Multiple far-field patterns are measured in focus by adjusting the deformation of the main reflector actively. Using the amplitude of far-field patterns, the phase distribution of the aperture can be retrieved by the phase-retrieval technique. Simulation results demonstrate the feasibility of this method. [ABSTRACT FROM AUTHOR]