Extraction and recognition of geographical features from paper maps

With the emergence of Geographical Information Systems (GIS), map acquisition and recognition have become hotly pursued topics, both by the industry and the academia. The paper presents a novel methodology for the extraction and recognition of symbol features from topographic maps. The method proceeds by separating the map into its constituent layers and then attempting to recognize the features in different layers on the basis of symbol-specific geometrical and morphological attributes. Text strings have also been separated. The output is obtained in the form of an ‘e-map’ that is vectorized and hence is suitable for GIS. To demonstrate the usefulness of the proposed system a simple database along with a query processing facility is constructed integrating the information obtained from the e-map and ‘some’ user inputs. The methodology has been observed to perform quite satisfactorily.     

Highly sensitive detection of exocytotic dopamine release using a gold-nanoparticle-network microelectrode

Here we report a new type of microelectrode sensor for single-cell exocytotic dopamine release. The new microsensor is built by forming a gold-nanoparticle (AuNP) network on a carbon fiber microelectrode. First a gold surface is obtained on a carbon fiber microdisk electrode by partially etching away the carbon followed by electrochemical deposition of gold into the pore. The gold surface is chemically functionalized with a sol-gel silicate network derived from (3-mercaptopropyl)trimethoxysilane (MPTS). A AuNP network is formed by immobilizing Au nanoparticles onto the thiol groups in the sol-gel silicate network. The AuNP-network microelectrode has been characterized by scanning electron microscopy (SEM) and steady-state voltammetry. The AuNP-network microelectrode has been used for amperometric detection of exocytotic dopamine secretion from individual pheochromocytoma (PC12) cells. The results show significant differences in the kinetic peak parameters including shorter rise time, decay time, and half-width as compared to a bare carbon fiber electrode equivalent. These results indicate AuNP-network microelectrodes possess an excellent sensing activity for single-cell exocytotic catecholamine release, specifically dopamine. Moreover, key advantageous properties inherent to bare carbon fiber microelectrodes (i.e., rigidity, flexibility, and small size) are maintained in addition to an observed prolonged shelf life stability and resistance to cellular debris fouling and dopamine polymerization.     

High-Performance Blue Perovskite Films and Micro-Arrays for Light-Emitting Diodes with Ionic Liquid Interlayer

Metal halide perovskites have attracted considerable attention for light-emitting diode (LED) applications due to their desirable optoelectronic properties including high brightness and color purity. However, the performance of blue perovskite LEDs (PeLEDs) remains inferior to their red and green counterparts. Herein, an ionic liquid (IL), specifically 1-butyl-3-methylimidazolium tetrafluoroborate is introduced as the interlayer on the hole transport layer (HTL). This IL demonstrates a strong interaction with the perovskite emissive layer, resulting in effective defect passivation and a shallower valence band maximum. Consequently, nonradiative recombination is reduced, and hole injection is enhanced. Additionally, a soft lithography method employing a transfer process is successfully developed that enables precise micropatterning of the perovskite light-emitting layer. Through these advancements, the IL-modified PeLED exhibits pure blue emission at 470 nm with a maximum luminance of 891 cd m⁻² and an impressive maximum EQE of 8.3%. Furthermore, the micro PeLED with an IL interlayer achieves a maximum luminance of 400 cd m⁻² and a maximum EQE of 3.9%.     

Decursinol Angelate Mitigates Sepsis Induced by Methicillin-Resistant Staphylococcus aureus Infection by Modulating the Inflammatory Responses of Macrophages

The herbal plant Angelica gigas (A. gigas) has been used in traditional medicine in East Asian countries, and its chemical components are reported to have many pharmacological effects. In this study, we showed that a bioactive ingredient of A. gigas modulates the functional activity of macrophages and investigated its effect on inflammation using a sepsis model. Among 12 different compounds derived from A. gigas, decursinol angelate (DA) was identified as the most effective in suppressing the induction of TNF-α and IL-6 in murine macrophages. When mice were infected with a lethal dose of methicillin-resistant Staphylococcus aureus (MRSA), DA treatment improved the mortality and bacteremia, and attenuated the cytokine storm, which was associated with decreased CD38⁺ macrophage populations in the blood and liver. In vitro studies revealed that DA inhibited the functional activation of macrophages in the expression of pro-inflammatory mediators in response to microbial infection, while promoting the bacterial killing ability with an increased production of reactive oxygen species. Mechanistically, DA treatment attenuated the NF-κB and Akt signaling pathways. Intriguingly, ectopic expression of an active mutant of IKK2 released the inhibition of TNF-α production by the DA treatment, whereas the inhibition of Akt resulted in enhanced ROS production. Taken together, our experimental evidence demonstrated that DA modulates the functional activities of pro-inflammatory macrophages and that DA could be a potential therapeutic agent in the management of sepsis.     

A Simple and Efficient Access to New Functionalized 4‐Phenacylideneflavenes#

An innovative and efficient approach towards diversity‐oriented synthesis of 4‐phenacylideneflavenes has been developed from substituted salicylaldehydes and acetophenones using iodine under solvent‐free conditions. Both symmetrical and unsymmetrical functionalized 4‐phenacylideneflavenes were synthesized in good to excellent yields and their mechanism of formation is discussed.     

Graphene-induced Pd nanodendrites: A high performance hybrid nanoelectrocatalyst

A facile and green approach has been developed for the in situ synthesis of hybrid nanomaterials based on dendrite-shaped Pd nanostructures supported on graphene （RG）. The as-synthesized hybrid nanomaterials （RG-PdnDs） have been thoroughly characterized by high resolution transmission electron microscopy, X-ray photoelectron spectroscop）~ atomic force microscop）~ Raman spectroscopy and electrochemical techniques. The mechanism of formation of such dendrite- shaped Pd nanostructures on the graphene support has been elucidated using transmission electron microscopy （TEM） measurements. The RG induces the formation of, and plays a decisive role in shaping, the dendrite morphology of Pd nanostructures on its surface. Cyclic voltammetry and chronoamperometry techniques have been employed to evaluate the electrochemical performance of RG-PdnDs towards oxidation of methanol. The electrochemical （EC） activities of RG-PdnDs are compared with graphene-supported spherical-shaped Pd nanostructures, Pd nanodendrites alone and a commercial available Pd/C counterpart. The combined effect of the graphene support and the dendrite morphology of RG-PdnDs triggers the high electrocatalytic activity and results in robust tolerance to CO poisoning.     

Sintering Characteristics of Indian Chrome Ore Fines

Chrome ore concentrate consists of high-temperature melting oxides such as Cr₂O₃, MgO, and Al₂O₃. The presence of these refractory constituents makes the ore a very high melting mineral. Hence, it is difficult to produce sinter from chrome ore by a pyrometallurgical route. Currently, chrome ore is ground to below 75 μm, pelletized, heat hardened through carbothermic reaction at 1300 °C to 1400 °C, and then charged into a submerged electric arc furnace (EAF), along with lumpy ore for ferrochrome/charge-chrome production. Electricity is a major cost element in this extraction process. This work explores the sinterability of chrome ore. The objective of this study was to: (1) determine whether chrome ore is sinterable and, if so, (2) ascertain ways of achieving satisfactory properties at a low temperature of sintering. Sintering of the raw material feed could be a way to reduce electricity consumption, because during sintering a partial reduction of minerals is expected along with agglomeration. Studies carried out by the authors show that it is possible to agglomerate chrome ore fines through sintering. The chrome ore sinter thus produced was found to be inferior in strength, comparable to that of an iron ore sinter, but strength requirements may not be the same for both. Because the heat generation during chrome ore sintering is high owing to some exothermic reactions, compared with iron ore, and because chrome ore contains a high amount of fines, shallow-bed-depth sinter cake production was attempted in the laboratory-scale pot-sintering machine. The sintered product was found to be a good conductor of electricity because of the presence of phases such as magnetite and maghemite. This characteristic of the chrome ore sinter will subsequently have a favorable impact in terms of power consumption during the production of ferrochrome in a submerged EAF. The sinter made was melted in the arc furnace and it was found that the specific melting energy is comparable to that of heat-hardened chrome ore pellets but lower than briquettes and lump ore.     

A family of thioxanthato ruthenium and osmium aryls

The title complexes of type M(RL²)(PPh₃)₂(CO)(S₂CSEt) ( 2a : M = Ru; 2b : M = Os) have been synthesized in excellent yields by reacting M(RL¹)(PPh₃)₂(CO)X ( 1a : M = Ru, × = Cl; 1b : M = Os, × = Br) with potassium ethyl thioxanthate and have been characterized with the help of spectral and electrochemical data. The RL² ligand in 2 is the imine-phenol tautomer of N-C₆H₄R(p)-4-methylsalicylaldimine (R = Me, MeO, Cl) coordinated at the carbanionic-C2 atom only while RL¹ in 1 is the iminium-phenolato tautomer chelated via carbanionic-C2 and phenolato-O atoms. The synthetic reaction is thus attended with tautomerization of the Schiff base ligand. It is also associated with a rotation of the ligand by ˜180° around the M–C bond in order to exclude steric repulsion. These features have been revealed by structure determination of 2a (R = Me). The metallated aldimine ring is found to be highly noncoplanar (dihedral angle ˜40°) with the thioxanthate chelate ring due to steric repulsion originating from the relatively large size of the sulfur atom. This phenomenon, which is absent in both the precursor 1 (R = Me) and in the carboxylate analogue Ru(MeL²)(PPh₃)₂(CO)(O₂CMe), 7 , has distinctive effects on bond parameters of 2a (R = Me). Thus the two Ru–P bonds in 2a (R = Me) differ in length by as much as 0.06 Å. The thioxanthate 2 is thermodynamically more stable than the precursor 1 as well as the carboxylate 7 . Accordingly, both of these are irreversibly transformed to 2a (R = Me) upon treatment with thioxanthate.     

Quality characteristics of kefir as a carrier for probiotic Lactobacillus rhamnosus GG

Kefir was prepared using kefir grains of different origins (US, Australia and India) and starter culture. The sensory scores for kefir made using starter culture and US kefir grains were significantly higher than for the other samples (P < 0.05). The index of viscosity was significantly higher (P < 0.05) in kefir prepared using Indian kefir grains. Shear stress–shear rate plots indicated yield stress in all kefirs. All samples exhibited shear‐thinning behaviour. The average count of Lactobacillus rhamnosus GG in kefir after incubation was 7.09 log CFU/g. No significant difference (P > 0.05) was observed in quality characteristics in kefir after the addition of LGG, indicating that it could be a potential probiotic carrier.     

Performance analysis of clustering-based fingerprinting localization systems

Wireless Networks - Localization is highly required to develop the smart-phone based pervasive computing applications. Because of very poor signal strength of global positioning system in indoor...