Starns, Jeffrey J.; Rotello, Caren M.; Ratcliff, Roger
Koen and Yonelinas (2010; K&Y) reported that mixing classes of targets that had short (weak) or long (strong) study times had no impact on zROC slope, contradicting the predictions of the encoding variability hypothesis. We show that they actually derived their predictions from a mixture unequal-variance signal detection (UVSD) model, which…
Background Costus speciosus (Koen ex.Retz.) Sm (Costaceae) is an Indian ornamental plant which has long been used medicinally in traditional systems of medicine. The plant has been found to possess diverse pharmacological activities. Rhizomes are used to treat pneumonia, rheumatism, dropsy, urinary diseases, jaundice, skin diseases and leaves are usedto treat mental disorders. Method Antibacterial and antifungal activities were tested using Disc diffusion method and Minimum Inhibitory Concentration (MIC). Column chromatography was used to isolate compounds from hexane extract. X-ray crystallography technique and GC-MS analysis were used to identify the compounds Results Antibacterial and antifungal activities were observed in hexane, chloroform, ethyl acetate and methanol extracts. Hexane extract of C.speciosus showed good activity against tested fungi also. Two sesquiterpenoid compounds were isolated (costunolide and eremanthin) from the hexane extract. Both the compounds did not inhibit the growth of tested bacteria. But, both the compounds inhibited the tested fungi. The compound costunolide showed significant antifungal activity. The MIC values of costunolide were; 62.5 μg/ml against Trichophyton mentagrophytes, 62. μg/ml against T. simii, 31.25 μg/ml against T. rubrum 296, 62.5 μg/ml against T. rubrum 57, 125 μg/ml against Epidermophyton floccosum, 250 μg/ml against Scopulariopsis sp, 250 μg/ml against Aspergillus niger, 125 μg/ml against Curvulari lunata, 250 μg/ml against Magnaporthe grisea. Conclusion Hexane extract showed promising antibacterial and antifungal activity. The isolated compound costunolide showed good antifungal activity. PMID:22397713
Starns, Jeffrey J; Rotello, Caren M; Ratcliff, Roger
Koen and Yonelinas (2010; K&Y) reported that mixing classes of targets that had short (weak) or long (strong) study times had no impact on ʐROC slope, contradicting the predictions of the encoding variability hypothesis. We show that they actually derived their predictions from a mixture unequal-variance signal detection (UVSD) model, which assumes 2 discrete levels of strength instead of the continuous variation in learning effectiveness proposed by the encoding variability hypothesis. We demonstrated that the mixture UVSD model predicts an effect of strength mixing only when there is a large performance difference between strong and weak targets, and the strength effect observed by K&Y was too small to produce a mixing effect. Moreover, we re-analyzed their experiment along with another experiment that manipulated the strength of target items. The mixture UVSD model closely predicted the empirical mixed slopes from both experiments. The apparent misfits reported by K&Y arose because they calculated the observed slopes using the actual range of ʐ-transformed false-alarm rates in the data, but they computed the predicted slopes using an extended range from - 5 to 5. Because the mixed predictions follow a slightly curved ʐROC function, different ranges of scores have different linear slopes. We used the actual range in the data to compute both the observed and predicted slopes, and this eliminated the apparent deviation between them.
Lakshmi, Vijai; Srivastava, Shishir; Mishra, Sunil Kumar; Srivastava, Mahendra Nath; Srivastava, Kumkum; Puri, Sunil Kumar
The antimalarial activity of Xylocarpus granatum fruits and their active constituents gedunin and xyloccensin-I were investigated using an in vitro model in this study. The chloroform fraction of X. granatum fruits was found to show promising antimalarial activity using an in vitro model of Plasmodium falciparum. On purification of the active fraction, four pure compounds were isolated and characterised, namely gedunin, photogedunin, xyloccensin-I and palmitic acid. Out of these only gedunin and xyloccensin-I were found to show activity equivalent to the parent active fraction in vitro model. PMID:21787243
Jang, Yoonhee; Mickes, Laura; Wixted, John T.
The slope of the z-transformed receiver-operating characteristic (zROC) in recognition memory experiments is usually less than 1, which has long been interpreted to mean that the variance of the target distribution is greater than the variance of the lure distribution. The greater variance of the target distribution could arise because the…
Selim, Samy; Al Jaouni, Soad
Costus speciosus is an important medicinal plant widely used in several indigenous medicinal formulations. The present study was conducted to evaluate the in vitro anti-inflammatory, antioxidant and antiangiogenic activities of diosgenin isolated from C. speciosus. The diosgenin was isolated from C. speciosus by HPTLC and its biological activities were studied by different protocols. The results demonstrated that LPS stimulated TNF-α generation in RAW 264.7 macrophage culture supernatant up to 3.7-fold of the control and that sample treatment (50 μg/mL) resulted in a highly significant inhibitory effect on LPS-stimulated TNF-α (p < 0.01) in a similar manner to methotrexate inhibitory effect. The tested sample possessed an effective antioxidant scavenging affinity against DPPH radicals as compared with the standard antioxidant activity of vitamin C. The results presented here may suggest that diosgenin isolated from C. speciosus possess anticancer, apoptotic and inhibitory effects on cell proliferation. PMID:26222585
Koen, Joshua D.; Yonelinas, Andrew P.
Koen and Yonelinas (2010) contrasted the recollection and encoding variability accounts of the finding that old items are associated with more variable memory strength than new items. The study indicated that (a) increasing encoding variability did not lead to increased measures of old item variance, and (b) old item variance was directly related…
Stinckens, A; Vereijken, A; Ons, E; Konings, P; Van As, P; Cuppens, H; Moreau, Y; Sakai, R; Aerts, J; Goddeeris, B; Buys, N; Vanmechelen, K; Cassiman, J J
The Cosmopolitan Chicken Project is an artistic undertaking of renowned artist Koen Vanmechelen. In this project, the artist interbreeds domestic chickens from different countries aiming at the creation of a true Cosmopolitan Chicken as a symbol for global diversity. The unifying theme is the chicken and the egg, symbols that link scientific, political, philosophical and ethical issues. The Cosmopolitan Chicken Research Project is the scientific component of this artwork. Based on state of the art genomic techniques, the project studies the effect of the crossing of chickens on the genetic diversity. Also, this research is potentially applicable to the human population. The setup of the CC®P is quite different from traditional breeding experiments: starting from the crossbreed of two purebred chickens (Mechelse Koekoek x Poule de Bresse), every generation is crossed with a few animals from another breed. For 26 of these purebred and crossbred populations, genetic diversity was measured (1) under the assumption that populations were sufficiently large to maintain all informative SNP within a generation and (2) under the circumstances of the CCP breeding experiment. Under the first assumption, a steady increase in genetic diversity was witnessed over the consecutive generations, thus indeed indicating the creation of a "Cosmopolitan Chicken Genome". However, under the conditions of the CCP, which reflects the reality within the human population, diversity is seen to fluctuate within given boundaries instead of steadily increasing. A reflection on this might be that this is because, in humans, an evolutionary optimum in genetic diversity is reached. Key words.
Lu, Li; Yan, Guozheng; Zhao, Kai; Xu, Fei
Constipation is a common yet distressing disease that has high rates of morbidity and impacts patients' quality of life. However, there is no perfect method to distinguish costive patients from healthy subjects. Is there chaos in human colonic activities? Are there any differences for the chaos indicators of colonic activities between healthy and costive subjects? Can these indicators distinguish patients with constipation from healthy subjects? To answer these questions, colonic pressure data from 16 healthy subjects and 48 patients with constipation were analyzed using the chaos theory. Three chaotic indicators [i.e., the largest Lyapunov exponent (LyE), correlation dimension (CorDim), and Kolmogorov entropy (KoEn)] were calculated and compared between groups with the Wilcoxon rank sum test. As a result, the LyE was greater than zero and the CorDim was fractioned, which showed that human colonic activities have clear chaotic characteristics. Statistically significant differences were observed between groups for CorDim (p < 0.05), whereas LyE did not show statistically significant differences between groups. The chaotic indicator of CorDim was able to differentiate between patients with constipation and healthy subjects. The chaos theory provides a new method for learning the nonlinear dynamics of human gastrointestinal activities.
Dr. Genryo Torafumi Okuyama, the second son of Dr. Genchu Okuyama of the Kaminoyama clan, was born on Dec. 4th, 1847. His elder brother Dr. Toraakira Okuyama was promoted to Dai Ikan (Senior Captain), the highest rank of medical officer in the Japanese Navy, and rendered distinguished services in the establishment of the naval medical systematization in the early Meiji era. Dr. Trafumi Okuyama, who was appointed as medical officer of the Yokohama army Hospital and transferred to Daibyoin in Edo, was engaged in medical treatment of injured soldiers during the Boshin-war in 1868. He went to Kagoshima with William Willis and as one of the founders of the Kagoshima Medical school, gave students education there. He resigned his naval position in 1874, when he was Dai Gun I (Senior Leutenant) and died at the age of 41 in April 16th 1887. Dr. Torafumi Okuyama compiled A medical vocabulary in English and Japanese ("Igo Ruizyu") and Deutsch-Japanisches Hand-Wörterbuch für Medizin ("Dokuwa Igaku Ziten) and published "Koen Hikki", the translation of the lectures by Dr. Edwin Wheeler. PMID:11618875
Leelapornpisid, Pimporn; Wickett, R Randall; Chansakaow, Sunee; Wongwattananukul, Nitima
Antioxidant activities of 10 essential oils and 10 absolutes extracted from Thai aromatic plants were evaluated and compared to thyme oil, trolox, quercetin, and kaempferol by two independent assays: the 2, 2-diphenyl-1-1-picrylhydrazyl (DPPH*) radical scavenging assay and the thiobarbituric acid reactive species (TBARS) assay for lipid peroxidation. We found that four essential oils including ginger oil (Zingiber officinale Roscoe), Wan-sao-long leaf oil (Amomum uliginosum Koen), lemongrass oil (Cymbopogon citratus), holy basil oil (Ocimum sanctum L.), and the absolute of dwarf ylang-ylang [Cananga odorata Hook. f. & Thomson var. fruticosa (Craib) J. Sinclair] exhibited high antioxidant activity in both DPPH and TBARS assays and possessed satisfactory fragrance properties. These were then combined into an essential oil blend (EOB) and retested for antioxidant activity. The EOB also exhibited high antioxidant activity in the above assays. It was then incorporated into a stable cream base as EOB body cream. The EOB body cream was found to be best able under storage in stress conditions and presented significantly higher antioxidant activity than its' cream base both before and after stability testing. The effect of EOB body cream on skin surface topography was evaluated in 29 healthy volunteers using the Skin Visiometer (SV 600 FW, CK Electronic GmbH, Germany). Three parameters, Ra, Rz (roughness), and surface, were analyzed. After 4 weeks of application, the EOB body cream showed significant reductions in surface and Rz compared with before treatment (p < 0.05, paired t-test), and with untreated and placebo treatment (p < 0.05, Duncan test). These results indicate that the essential oils and absolutes from Thai plants may serve as potential sources of natural antioxidants for spa and cosmetic products designed to prevent or treat signs of skin aging. PMID:26665978
Stinckens, A.; Vereijken, A.; Ons, E.; Konings, P.; Van As, P.; Cuppens, H.; Moreau, Y.; Sakai, R.; Aerts, J.; Goddeeris, B.; Buys, N.; Vanmechelen, K.; Cassiman, J.J.
Abstract The Cosmopolitan Chicken Project is an artistic undertaking of renowned artist Koen Vanmechelen. In this project, the artist interbreeds domestic chickens from different countries aiming at the creation of a true Cosmopolitan Chicken as a symbol for global diversity. The unifying theme is the chicken and the egg, symbols that link scientific, political, philosophical and ethical issues. The Cosmopolitan Chicken Research Project is the scientific component of this artwork. Based on state of the art genomic techniques, the project studies the effect of the crossing of chickens on the genetic diversity. Also, this research is potentially applicable to the human population. The setup of the CC®P is quite different from traditional breeding experiments: starting from the crossbreed of two purebred chickens (Mechelse Koekoek x Poule de Bresse), every generation is crossed with a few animals from another breed. For 26 of these purebred and crossbred populations, genetic diversity was measured (1) under the assumption that populations were sufficiently large to maintain all informative SNP within a generation and (2) under the circumstances of the CCP breeding experiment. Under the first assumption, a steady increase in genetic diversity was witnessed over the consecutive generations, thus indeed indicating the creation of a “Cosmopolitan Chicken Genome”. However, under the conditions of the CCP, which reflects the reality within the human population, diversity is seen to fluctuate within given boundaries instead of steadily increasing. A reflection on this might be that this is because, in humans, an evolutionary optimum in genetic diversity is reached. Key words: PMID:26977265
Liljenström, Hans; Svedin, Uno
1. System features, dynamics, and resilience - some introductory remarks / Hans Liljenström & Uno Svedin -- pt. I. The "vertical" system structure and meso-level characteristics. 2. Mesoscopic levels in science - some comments / Hermann Haken. 3. The necessity for mesoscopic organization to connect neural function to brain function / Walter J. Freeman. 4. Dynamic state transitions in the nervous system: from ion channels to neurons to networks / Peter Århem ... [et al.]. 5. A revolution in the Middle Kingdom / Robert E. Ulanowicz. 6. The meso-scale level of self-maintained reflective systems / Abir U. Igamberdiev -- pt. II. Inner and outer dynamics. 7. Time rescaling and generalized entropy in relation to the internal measurement concept / Igor Rojdestvenski & Michael G. Cottam. 8. Studying dynamic and stochastic systems using Poisson simulation / Leif Gustafsson. 9. Resource dynamics, social interactions, and the tragedy of the commons / Alia Mashanova & Richard Law. 10. Stability of social interaction / Sjur D. Flåm -- pt. III. Resilience and shocks. 11. Systems, shocks and time bombs / Nick Winder. 12. Biodiversity decreases the risk of collapse in model food webs / Charlotte Borrvall, Maria Christianou & Bo Ebenman. 13. A long-term perspective on resilience in socio-natural systems / Sander E. van der Leeuw & Christina Aschan-Leygonie. 14. Resilience in utility technologies / Roger Seaton. 15. Economic growth under shocks: path dependencies and stabilization / Yuri M. Ermoliev, Tatiana Y. Ermolieva & Vladimir I. Norkin. 16. Risk and crises management in complex systems / Koen Bertels, Jean-Marie Jacques & Magnus Boman. 17. Bridges, connections and interfaces - reflections over the meso theme / Uno Svedin & Hans Liljenström.
Zhaoping, Li; Guyader, Nathalie; Lewis, Alex
Experimental evidence has given strong support to the theory that the primary visual cortex (V1) realizes a bottom-up saliency map (A. R. Koene & L. Zhaoping, 2007; Z. Li, 2002; L. Zhaoping, 2008a; L. Zhaoping & K. A. May, 2007). Unlike the conventional models of texture segmentation, this theory predicted that segmenting two textures in an image I(rel) comprising obliquely oriented bars would become much more difficult when a task-irrelevant texture I(ir) of spatially alternating horizontal and vertical bars is superposed on the original texture I(rel). The irrelevant texture I(ir) interferes with I(rel)'s ability to direct attention. This predicted interference was confirmed (L. Zhaoping & K. A. May, 2007) in the form of a prolonged task reaction time (RT). In this study, we investigate whether and how 3D depth perception, believed to be processed mostly beyond V1 and starting in V2 (J. S. Bakin, K. Nakayama, & C. D. Gilbert, 2000; B. G. Cumming & A. J. Parker, 2000; F. T. Qiu & R. von der Heydt, 2005; R. von der Heydt, H. Zhou, & H. S. Friedman, 2000), contribute additionally to direct attention. We measured the reduction of the interference or the RT when the position of the texture grid for I(ir) was offset horizontally from that for I(rel), forming an offset, 2D, stimulus. This reduction was compared with that when this positional offset was only present in the input image to one eye, or when it was in the opposite directions in the images for the two eyes, creating a 3D stimulus with a depth separation between I(ir) and I(rel). The contribution by 3D processes to attentional guidance would be manifested by any extra RT reduction associated with the 3D stimulus over the offset 2D stimulus. This 3D contribution was not present unless the task was so difficult that RT (by button press) based on 2D cues alone was longer than about 1 second. Our findings suggest that, without other top-down factors, V1 plays a dominant role in attentional guidance during an