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21.
BACKGROUND: Frith & Done (1988) have proposed that the experience of alien control symptoms in schizophrenia is related to a failure by such individuals to monitor effectively their own willed intentions, actions and thoughts. METHOD: To examine this hypothesis, a heterogeneous group of 35 patients, all carrying a DSM-III-R diagnosis of schizophrenia (or schizophreniform psychosis) and 24 non-patient controls, completed a battery of neuropsychological and cognitive tests, which inter alia, included four putative measures of self-monitoring. Patients took part in a detailed clinical interview to assess current levels of symptomatology. RESULTS: Patients generally performed at a lower level on most components of the test battery, including the four self-monitoring tests. Moreover, patients currently experiencing symptoms of alien control tended to experience greater difficulty with each of the self-monitoring tests; an effect that was relatively independent of neuropsychological or general cognitive function. CONCLUSIONS: The relationship between poor self-monitoring and the presence of alien control symptoms provides support for Frith & Done's account of the origins of these symptoms in schizophrenia. 相似文献
22.
The successive approximation technique is faster than most other methods of analogue-to-digital conversion. The main drawback is that it normally uses a multiplicity of high precision components. This paper describes a method in which the signal is recycled through the same conversion stage by using sample and hold circuits. 相似文献
23.
Stirling WL Tsai CC Haselton HH Schechter DE Whealton JH Dagenhart WK Davis RC Gardner WL Kim J Menon MM Ryan PM 《The Review of scientific instruments》1979,50(5):523
The properties of an intense neutral beam injector, the modified duoPIGatron ion source, are discussed and compared with other injectors. For this source (a) beam composition for hydrogen is approximately (85+/-5) % monatomic, (b) nucleon gas efficiency is 50%, (c) the electrical efficiency of ion generation is 1.1 A/kW, and (d) up to 52% of the input power is delivered in the ion and neutral beam to a target subtending a half angle of 1.8 degrees x1.4 degrees . 相似文献
24.
Janelle Cheung Noor A. Lokman Riya D. Abraham Anne M. Macpherson Eunice Lee Frank Grutzner Nicolae Ghinea Martin K. Oehler Carmela Ricciardelli 《International journal of molecular sciences》2021,22(1)
Follicle-stimulating hormone (FSH) and luteinising hormone (LH) play important roles in regulating cell growth and proliferation in the ovary. However, few studies have explored the expression of FSH and LH receptors (FSHR and LHCGR) in ovarian cancer, and their functional roles in cancer progression remain inconclusive. This study investigated the potential impact of both mRNA (FSHR, LHCGR) and protein (FSHR, LHCGR) expression on ovarian cancer progression using publicly available online databases, qRT-PCR (high grade serous ovarian cancers, HGSOC, n = 29 and benign ovarian tumors, n = 17) and immunohistochemistry (HGSOC, n = 144). In addition, we investigated the effect of FSHR and LHCGR siRNA knockdown on the pro-metastatic behavior of serous ovarian cancer cells in vitro. High FSHR or high LHCGR expression in patients with all subtypes of high-grade ovarian cancer was significantly associated with longer progression-free survival (PFS) and overall survival (OS). High FSHR protein expression was associated with increased PFS (p = 0.050) and OS (p = 0.025). HGSOC patients with both high FSHR and high LHCGR protein levels had the best survival outcome, whilst both low FSHR and low LHCGR expression was associated with poorest survival (p = 0.019). Knockdown of FSHR significantly increased the invasion of serous ovarian cancer cells (OVCAR3 and COV362) in vitro. LHCGR knockdown also promoted invasion of COV362 cells. This study highlights that lower FSHR and LHCGR expression is associated with a more aggressive epithelial ovarian cancer phenotype and promotes pro-metastatic behaviour. 相似文献
25.
Linping Chan Fazel Naghdy David Stirling 《Journal of Intelligent and Robotic Systems》2017,85(3-4):679-692
A novel algorithm for simultaneous force estimation and friction compensation of constrained motion of robot manipulators is presented. This represents an extension of the improved extended active observer (IEAOB) algorithm reported earlier and proposes a higher order IEAOB or N?th order IEAOB (IEAOB ?N) for a n?DOF robot manipulator. Central to this observer is the use of extra system states modeled as a Gauss-Markov (GM) formulation to estimate the force and disturbances including robot inertial parameters and friction. The stability of IEAOB ?N is verified through stability analysis. The IEAOB-1 is validated by applying it to a Phantom Omni haptic device against a Nicosia observer, disturbance observer (DOB)/reaction torque observer (RTOB), and nonlinear disturbance observer (NDO), respectively. The results show that the proposed IEAOB-1 is superior to the compared observers in terms of force estimation. Then, the performance of the IEAOB ? N is experimentally studied and compared to the IEAOB-1. Results demonstrate that the IEAOB ? N has an improved capability in tracking nonlinear external forces. 相似文献
26.
Model predictive satisficing fuzzy logic control 总被引:2,自引:0,他引:2
27.
V. Chechik R. M. Crooks C. J. M. Stirling 《Advanced materials (Deerfield Beach, Fla.)》2000,12(16):1161-1171
Self‐assembled monolayers (SAMs) are excellent models for studying interfacial reactions. Here monolayer chemistry is reviewed, focusing on the features that have no analogues in solution chemistry. The growth of surface‐attached polymers, intrafilm reactions, chemistry, photochemistry and reactivity issues are all discussed. 相似文献
28.
29.
Smithwick M Norstrom RJ Mabury SA Solomon K Evans TJ Stirling I Taylor MK Muir DC 《Environmental science & technology》2006,40(4):1139-1143
Perfluoroalkyl substances are globally distributed anthropogenic contaminants. Their production and use have increased dramatically from the early 1980s. While many recent publications have reported concentrations of perfluorooctane sulfonate (PFOS) and other perfluoroalkyl acids (PFAs) in biotic and abiotic samples, only limited work has addressed temporal trends. In this study we analyzed archived polar bear(Ursus maritimus) livertissue samples from two geographic locations in the North American Arctic, collected from 1972 to 2002. The eastern group, taken from the vicinity of northern Baffin Island, Canada, comprised 31 samples, and the western group, from the vicinity of Barrow, Alaska, comprised 27 samples. Samples were analyzed for perfluorocarboxylic acids (PFCAs) from carbon chain length C8 to C15, perfluorohexane sulfonate, PFOS, the neutral precursor perfluorooctane sulfonamide (PFOSA), as well as 8:2 and 10:2 fluorotelomer acids and their alpha,beta unsaturated acid counterparts. Concentrations of PFOS and PFCAs with carbon chain lengths from C9 to C11 showed an exponential increase between 1972 and 2002 at both locations. Doubling times ranged from 3.6 +/- 0.9 years for perfluorononanoic acid in the eastern group to 13.1 +/- 4.0 years for PFOS in the western group. PFOSA showed decreasing concentrations over time at both locations, while the remaining PFAs showed no significant trends or were not detected in any sample. The doubling time for PFOS was similar to the doubling time of production of perfluoroctylsulfonyl-fluoride-based products during the 1990s. 相似文献
30.
Stephen T. Talcott Janelle E. Peele Carmen H. Brenes 《Food research international (Ottawa, Ont.)》2005,38(10):1205-1212
Isoflavonoid extracts from red clover (Trifolium pratense) leaves were found to enhance overall color and stability of anthocyanin 3,5-diglucosides present in muscadine grape (Vitis rotundifolia) juice and wine through intermolecular copigmentation reactions. Predominant isoflavonoids present in red clover included formononetin, biochanin A, and prunetin and were the major polyphenolics identified to influence anthocyanin color and stability. Since red clover isoflavonoids have poor water solubility characteristics, this allowed for removal of extraneous non-isoflavonoid compounds using hot water and subsequent extraction with ethanol. Isoflavonoid solubility was evaluated as a function of ethanol concentration with recoveries up to 57% found in 20% solutions. Changes in maximum absorbance, total soluble phenolics, isoflavonoids, and anthocyanins were evaluated in muscadine juice and wine following the addition of isoflavonoid extracts with maximum color enhancement found at an anthocyanin to cofactor ratio of 1:8, after which their solubility was prohibitive. Additionally, dried leaves and ethanolic extracts of red clover were added prior to and following fermentation of muscadine wine (11% ethanol) stimulating the natural copigmentation that takes place during red wine fermentation and aging processes. Once fermentation was complete, finished wines were evaluated over a 9-week storage period at 20 and 37 °C. Despite low levels of isoflavonoids present, color improvement and anthocyanin stability was observed in the wines during storage. Little information is available on copigmentation reactions occurring in actual food systems, yet red clover isoflavonoids proved to be novel and effective color enhancing compounds when used in low concentrations in young muscadine wines. 相似文献