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The ability to represent numbers is a key attribute for both humans and animals. Recent developments in the understanding of numerical processing has led to the proposal that humans utilise two independent representations of number, one for real numbers and another for integers. We describe a computational model of small number detection to explore the relationship between these core systems of number. We use a combination of unsupervised and supervised neural networks to simulate the interaction between the real and integer representations. For real values we use a self-organised spatial representation of number. For integer values we use a supervised network motivated by linguistic processing. During training and testing, the networks exhibit behavioural characteristics such as the number size and numerical distance effects. Each representation is combined using the mixture-of-experts architecture that allows us to model the subitization limit (the maximum number of visual stimuli that can be accurately quantified almost immediately) as the competitive allocation of representations for number detection, where the crossover point between deploying the real and integer representations of number is obtained through a process of learning. Our results suggest that the existence of two core systems of number is at least computationally plausible and further suggests that the subitization limit emerges through the interaction of spatial and linguistic numerical processing. This provides computational evidence for one way in which small and large numbers are related in humans.  相似文献   
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A series of new tetrasubstituted thiophenes (4a-4i, 5a-5i and 6a-6f) have been synthesized as novel anti-inflammatory agents and were evaluated for their anti-inflammatory activity in carrageenin-induced rat hind paw oedema model at the doses of 10, 20 and 40mg/kg body weight. Among ester series, the best compound 4c showed 71% protection at 10mg/kg, 72% at 20mg/kg, and 76% at 40mg/kg to inflamed paw; while in acid series 5a showed 79% protection at 10mg/kg, 80% at 20mg/kg, and 70% at 40mg/kg, and 5c showed 72% protection at 10mg/kg, 75% at 20mg/kg, and 69% at 40mg/kg, to inflamed paw. In case of oxime series 6a-6f, the anti-inflammatory activities of the candidates were found to be poor as compared to acid and ester series. It was found on the basis of SAR studies of target compounds, that the presence of OCH(3) at R(2) position and H, OCH(3) at R(1) are one of the requirements for eliciting comparable anti-inflammatory activity in both tetrasubstituted thiophenes' ester and acid series. Compounds 4a-4i, 5a-5i were investigated for their analgesic activity in acetic acid induced writhing response model at 10mg/kg dose. Among the ester series compound 4e showed maximum protection of 60%, while 4a, 4b, and 4i exhibited 55%, 45%, and 43% protection, respectively. The result showed that presence of H, Cl at R(1) and OCH(3), CH(3) at R(2) in tetrasubstituted thiophene ester series enhances their analgesic activity. The candidates of acid series 5a-5i showed poor analgesic activity as compared to the standard drug ibuprofen. Compounds 4a-4i, 5a-5i were evaluated for their in vitro antioxidant nitric oxide radical scavenging assay. Among the ester series 4a showed maximum in vitro nitric oxide radical scavenging activity having IC(50) value 30.08microg/ml while in acid series 5a has IC(50) value 25.20microg/ml. The results showed that the presence of R(1)=H, R(2)=OCH(3) and R(1)=R(2)=OCH(3) enhances nitric oxide radical scavenging property in tetrasubstituted thiophenes' acid series.  相似文献   
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Rationalizing has become a new trend in the world of science and technology. Nanotechnology has ascended to become one of the most favorable technologies, and one which will change the application of materials in different fields. The quality of dental biomaterials has been improved by the emergence of nanotechnology. This technology manufactures materials with much better properties or by improving the properties of existing materials. The science of nanotechnology has become the most popular area of research, currently covering a broad range of applications in dentistry. This review describes the basic concept of nanomaterials, recent innovations in nanomaterials and their applications in restorative dentistry. Advances in nanotechnologies are paving the future of dentistry, and there are a plenty of hopes placed on nanomaterials in terms of improving the health care of dental patients.  相似文献   
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This study was aimed at developing green histidine-modified Fe3O4 nanoparticles (His-MNPs) for the adsorptive removal of Acid Black 1 (AB1) from aqueous solution. The His-MNPs were characterized by atomic force microscopy, scanning electron microscopy-energy dispersive X-ray spectrometry, infra-red spectra and thermogravimetry. These MNPs were spherical (average diameter 11–28 nm) with polydispersity index of 1.40 and about 13% mass coating of histidine. To optimize AB1 adsorption on His-MNPs and understand its mechanism, the influences of different operational variables (pH, adsorbent amount, temperature, initial AB1 concentration, contact time, ionic strength, etc.) on adsorption were examined with adsorption isotherms, kinetics and thermodynamic studies. The AB1 adsorption from water was fast with equilibrium time ≤ 45 min. The adsorption equilibrium was best fitted to the Langmuir isotherm model (qmax = 166.7 mg g−1 at the adsorbent dose of 0.2 g L−1, temperature 30 °C and pH 4). The linearity order for other isotherms was as follows: Dubinin–Radushkevich (D–R) < Temkin < Freundlich. The kinetics of the AB1 adsorption demonstrated the best compliance with the pseudo-second-order model, predominantly controlled by film diffusion as compared to intraparticle diffusion. Thermodynamic parameters (ΔH° and ΔG°) reflected the exothermic and spontaneous adsorption process. The values of ΔG°, ΔH°, activation energy and D–R free adsorption energy were all consistent with the physisorptive removal of AB1. The spectral (electronic and IR) and pH studies further corroborated the mechanism of AB1 removal by His-MNPs. The His-MNPs showed efficient adsorption, easy regeneration and excellent reusability, assisted by their pH-responsive properties. The prepared adsorbent can provide a safe, effective and economical alternative strategy for removing azo dyes from wastewater.

Effective and eco-friendly separation of Acid Black 1 dye from water by electrostatic adsorption onto reusable Histidine-Fe3O4 nanoparticles, credited to their pH-responsiveness.  相似文献   
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This report describes the case of a 42 years old male patient whose one right hand finger was partially lost as a result of occupational trauma. A modified impression technique was used for impression making and wax pattern was fabricated using the normal hand of the same patient. A special type of wax was formulated to make a pattern which was easily molded and carved. Two indexed casts were used to determine the length of fingers. Intrinsic and extrinsic staining was also done to match the adjacent skin colour. A ring was used as a retentive method. The patient was highly appreciative of the social acceptance after he started wearing the finger prosthesis.  相似文献   
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Carcinosarcoma of the breast is an extremely rare and aggressive tumour with two distinct cell lines comprising epithelial and mesenchymal components, with few cases reported in the literature. The prognosis of carcinosarcoma breast is less favourable compared to more common types of breast cancers such as infiltrating ductal or lobular carcinomas. These tumours form a diagnostic and therapeutic challenge. A case of carcinosarcoma breast in a 36 years old woman is presented here.  相似文献   
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