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41.
Ordinal knowledge is a fundamental aspect of advanced cognition. It is self-evident that humans represent ordinal knowledge, and over the past 20 years it has become clear that nonhuman primates share this ability. In contrast, evidence that nonprimate species represent ordinal knowledge is missing from the comparative literature. To address this issue, in the present experiment we trained pigeons on three 4-item lists and then tested them with derived lists in which, relative to the training lists, the ordinal position of the items was either maintained or changed. Similar to the findings with human and nonhuman primates, our pigeons performed markedly better on the maintained lists compared to the changed lists, and displayed errors consistent with the view that they used their knowledge of ordinal position to guide responding on the derived lists. These findings demonstrate that the ability to acquire ordinal knowledge is not unique to the primate lineage. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
42.
Edyta Hetmaniok Damian Słota Roman Wituła Adam Zielonka 《Computers & Mathematics with Applications》2011,61(8):1931-1934
In this paper, a comparison between two methods: the Adomian decomposition method and the variational iteration method, used for solving the moving boundary problem, is presented. Both of the methods consist in constructing the appropriate iterative or recurrence formulas, on the basis of the equation considered and additional conditions, enabling one to determine the successive elements of a series or sequence approximating the function sought. The precision and speed of convergence of the procedures compared are verified with an example. 相似文献
43.
Svetlana Cicmil Terry Williams Janice Thomas Damian Hodgson 《International Journal of Project Management》2006,24(8):675
This paper puts forth the somewhat controversial position that what is needed to improve project management in practice is not more research on what should be done or the frequency and/or use of traditional project management practices. We argue that while a great deal is written about traditional project management we know very little about the “actuality” of project based working and management. This paper formulates a research approach that takes seriously practitioner’s lived experience of projects. We explore the ontological, epistemological and methodological assumptions underlying this kind of research and provide examples of some project management research originating from this perspective. We conclude by summarizing the findings from these studies and providing insights into the map ahead for future such research. In this kind of work the attention is refocused on praxis, on context-dependent judgement, on situational ethics and on reflexivity which enables social actors to see how power actually functions in context. 相似文献
44.
A considerable proportion of cases of myeloproliferative and lymphoproliferative disorders exhibit renal involvement. However, it is unclear whether the cytologic features, immunophenotype or grade of malignancy of the cells infiltrating the kidney differ from those of the primary tumor. This study was performed on 120 autopsy cases with the following diagnoses: acute myelogenous leukemia (AML, n = 22; subtypes M1 + M2, n = 12, subtype M4, n = 10), chronic myelogenous leukemia (CML, n = 7), agnogenic myeloid metaplasia/myelofibrosis (AMM/MF, n = 6), acute lymphocytic leukemia (ALL, n = 6), chronic lymphocytic leukemia (CLL, n = 9), other low-grade non-Hodgkin's lymphomas (low-grade NHL, n = 24), high-grade NHL (n = 21) and multiple myeloma (MM, n = 25). Renal involvement was investigated by light microscopy and immunohistochemistry. It was found in 34% of the cases, and was most common in ALL (83%) and low-grade NHL (50%) and least common in high-grade NHL (10%) and MM (12%). Dense infiltration of almost the entire kidney was most commonly seen in AML, low-grade NHL and ALL. Infiltration was bilateral and involved both the cortex and medulla in the majority of cases. When involvement of other organs was compared with that of the kidney, the lung was found to be involved in approximately the same number of cases, but liver involvement was more common and heart involvement less common. Reactive lymphocytic infiltration of the kidney was found in 18 of the 120 cases (15%), and was distinguished from scanty tumorous infiltration by immunohistochemical staining. No major phenotypical differences were found between the tumor cells infiltrating the kidney and those of the primary tumors in the bone marrow or lymph nodes. However, in one case of CML, the cells infiltrating the kidney were negative for KP1 and chloroacetate esterase, but could be identified by reactivity for CD34. The grade of malignancy in NHL was similar in both the nodal and renal manifestations. 相似文献
45.
The results of a survey conducted at a South Island, New Zealand, abattoir are presented. Two-hundred-and-eighteen samples taken from ovine carcasses and the environment were analysed. The traditional cold enrichment, i.e. 4 degrees C for up to 16 weeks, was used. No isolations of listeriae were made from freshly dressed carcasses or from surfaces with which meat makes contact. However, seven isolates of Listeria monocytogenes were obtained from cold rooms operating at 5 degrees C and which are used to store carcasses. Also, a single isolate of L. ivanovii was obtained from a mesh screen strainer of the waste water treatment plant located near the works. The study indicates that ovine carcasses can be prepared free of L. monocytogenes, that cold rooms may be a source of these microorganisms and it also reconfirms that listeriae can be found in soil and fodder of animal paddocks adjacent to the abattoir. 相似文献
46.
Functional Chromatography Reveals Three Natural Products that Target the Same Protein with Distinct Mechanisms of Action
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Dr. Min Jin Kang Dr. Tongde Wu Dr. E. M. Kithsiri Wijeratne Eric C. Lau Damian J. Mason Celestina Mesa Joseph Tillotson Prof. Dr. Donna D. Zhang Prof. Dr. A. A. Leslie Gunatilaka Dr. James J. La Clair Prof. Dr. Eli Chapman 《Chembiochem : a European journal of chemical biology》2014,15(14):2125-2131
Access to lead compounds with defined molecular targets continues to be a barrier to the translation of natural product resources. As a solution, we developed a system that uses discrete, recombinant proteins as the vehicles for natural product isolation. Here, we describe the use of this functional chromatographic method to identify natural products that bind to the AAA+ chaperone, p97, a promising cancer target. Application of this method to a panel of fungal and plant extracts identified rheoemodin, 1‐hydroxydehydroherbarin, and phomapyrrolidone A as distinct p97 modulators. Excitingly, each of these molecules displayed a unique mechanism of p97 modulation. This discovery provides strong support for the application of functional chromatography to the discovery of protein modulators that would likely escape traditional high‐throughput or phenotypic screening platforms. 相似文献
47.
OBJECTIVE: In women who use oral contraceptives with low estrogen doses, a quiescent endometrium is frequently produced. Further reduction of the estrogen dose would not be expected to alter this effect. In this open-label study, the effects on the endometrium of a monophasic oral contraceptive containing 75 micrograms gestodene and 20 micrograms ethinylestradiol were assessed. METHOD: Biopsies were performed on 25 women on therapy. The biopsies were performed during the late luteal phase (last 7 days) in the pretreatment cycle and during days 15-21 in cycle 6 for 13 subjects (Group A) and during days 15-21 in cycle 3 and during the late luteal phase (last 7 days) in the post-treatment cycle for 12 subjects (Group B). RESULTS: All subjects completed six cycles of treatment. Nine of 13 subjects pretreatment and nine of 12 subjects at cycle 3 were characterized by the pathologist as having a secretory endometrium. Four of 13 subjects at cycle 6 and ten of 11 subjects post-treatment also demonstrated a secretory endometrium. Pre-decidual changes were seen in one, two, two and zero subjects at pretreatment, after three cycles, six cycles, and post-treatment, respectively. Six subjects had an atrophic endometrium at cycle 6. CONCLUSIONS: With monophasic gestodene/ethinylestradiol 75 micrograms/20 micrograms, a secretory or inactive endometrium was present in most subjects. Thus, the effects on the endometrium of this oral contraceptive containing a reduced estrogen dose are consistent with those produced by other low-estrogen-dose combination oral contraceptives. 相似文献
48.
Decomposition of vegetation cover into woody and herbaceous components using AVHRR NDVI time series 总被引:3,自引:0,他引:3
Hua Lu Michael R. RaupachTim R. McVicar Damian J. Barrett 《Remote sensing of environment》2003,86(1):1-18
A method is developed to separate Normalised Difference Vegetation Index (NDVI) time series data into contributions from woody (perennial) and herbaceous (annual) vegetation, and thereby to infer their separate leaf area indices and cover fractions. The method is formally consistent with fundamental linearity requirements for such a decomposition, and is capable of rejecting contaminated NDVI data. In this study, estimates of annual averaged woody cover and monthly averaged herbaceous cover over Australia are determined using Pathfinder AVHRR Land series (PAL) Global Area Coverage (GAC) Advanced Very High Resolution Radiometer (AVHRR) NDVI data from 1981 to 1994, together with ground-based measurements of leaf area index (LAI) and foliage projective cover (FPC). 相似文献
49.
M Stoian C Dragomir C D?sc?lescu S P?dureanu M Damian 《Canadian Metallurgical Quarterly》1995,99(1-2):82-89
Pathological aspects in 100 cases of operated A.P. different in severity are not strictly related to aetiological conditions. Clinical observations have suggested some components of pathogenesis: obstruction of bilio-pancreatic inflow in duodenum at the beginning of the attack, bilio-pancreatic reflux on cholangiograms, strong secretory digestive stimulation before attack. Some experimental animals models (dogs) which can mimic pathogenic mechanism (obstruction of pancreatic flow, common bilio-pancreatic duct, closed duodenal loop, acute cholecystitis) have revealed characteristic pathological changes depending on the initiating process. Our conclusion that severity of pathological changes in A.P. are determined by the initiating mechanisms which may differ in some aetiological condition or may be common for different ones. 相似文献
50.
EM Cornford S Hyman ME Cornford RT Damian MJ Raleigh 《Canadian Metallurgical Quarterly》1998,57(7):699-713
Cellular distribution of the Glut1 glucose transporter in normal primate brains was analyzed by immunogold electron microscopy. Two configurations of endothelial Glut1 glucose transporter (high and low density capillaries) have been found in resections of traumatically injured and epileptogenic human brain; the objective of the present study was to ascertain whether these same 2 capillary populations, expressing high and low glucose transporter densities, were the common configuration in normal brain. The relative numbers of Glut1 glucose transporter-associated gold particles on luminal and abluminal endothelial cell membranes were determined within the cerebral cortex of several normal, nonhuman primates. Low Glut1 densities were seen in brain endothelia of both the rhesus and squirrel monkey cortex, with slightly greater quantities of Glut1 in vervet monkey cortices. The Glut1 transporter was most highly expressed in the baboon cortex, approaching the concentrations seen in human brains. In the rhesus, squirrel, and vervet monkeys, Glut1 concentrations were greater on the abluminal than luminal capillary membranes. In contrast, mean luminal membrane Glut1 concentrations were greater in baboons, resembling the distribution seen in the human brain. Brain regional differences in transporter concentration were seen in comparing membrane densities in the baboon cortex (approximately 15 Glut1-gold particles per micrometer), hippocampus (approximately 12 Glut1 gold particles per micrometer), cerebellum (approximately 6 Glut1-gold particles per micrometer), and retinal microvasculature (approximately 20 Glut1-gold particles per micrometer). We conclude that a single, uniform Glut1 distribution characterizes brain capillaries of normal nonhuman primates, and hypothesize that the presence of high and low density glucose transporter endothelial cells (seen in human traumatic injury and seizure resections) represents a pathologic response to brain insult. 相似文献