5,585 research outputs found
Clinical update on K-Ras targeted therapy in gastrointestinal cancers
No full textKRAS mutations are common in pancreatic and colorectal cancers and are associated with lack of response to anti-epidermal growth factor receptor therapy. Ras is an established therapeutic target that has long eluded efforts to develop specific inhibitors, while targeting downstream signaling pathways has proven largely ineffective, highlighting a need for rational combination strategies to overcome resistance. Recently, renewed interest in directly targeting Ras has led to the development of several small-molecule inhibitors that bind directly to K-Ras or its effector proteins, downregulation of K-Ras expression using therapeutic antisense oligonucleotides or siRNAs, and targeting scaffold proteins such as kinase suppressor of Ras. Indirect approaches to inhibiting K-Ras include combining inhibitors of the mitogen-activated protein kinase pathway with novel targeted agents. Immunotherapy in early studies has also shown clinical promise. This review summarizes the current evidence for each of these approaches
A 1531.52 nm Tunable Diode Laser-Based System for High-Sensitivity Remote Monitoring of Acetylene and Ammonia Leaks in Industrial Plants
Get PDFWe demonstrate a 1531.52 nm tunable diode laser -based sensor system that can be used to build a dense, wide-area sensor network for in situ multi-point detection of acetylene (C2H2) and ammonia (NH3) leaks in industrial safety applications. The detection limit of the sensor is 16 ppm for C2H2 and 228 ppm for NH3 using a 28 cm long single-pass gas cell. High temperature measurements are also demonstrated in a tube furnace using a 1392.54 nm laser-based sensor. The accuracy of temperature measurement is 92.13% at 500 K and 96.79% at 700 K
Energy used by transport systems in India: the role of the urban population, sources, alternative modes and quantitative analyses
No full textThe purpose of this work is to at first give a general overview of the state-of-the-art transportation system in India, outlining the related energy consumption for different modes of transport; trains, light trucks, heavy trucks, buses, three wheelers, two wheelers, cars and jeeps, with their consequent estimated emissions. These elements are essential for the preparation of high-level strategic transport planning for the issue of energy as a whole, to help India make the right choices for the most suitable transportation systems. A relevant consideration at the base of this work is the high urbanization and motorization level in Indian metropolises in the last years. In order to provide an appropriate analysis on energy consumption, that is fully satisfactory from a methodological viewpoint and related to all transport systems, the well-to-wheel WTW index was adopted, taking into account that, especially in the urban context, that shorter journeys would easily be addressed by electric traction, while this is not taken for granted at all, according to the overall energy chain consumption and specific considerations on energy available in India when compared to Europe, which are included. Pursuing a WTW global index for India, that takes into account both the energy and environmental aspects on a uniform basis, is an important aim. It allows the best choices to be made as well as enabling the comparison between some of the most important means of transport, powertrain and fuel options on the Indian market, mainly the urban one
Transport and energy in India. Energy used by Indian transport systems and consequent emissions: the need for quantitative analyses (Well-to-Wheel, Lifecycle)
Get PDFThe purpose of this work is, at first, a general overview on the state-of-art of the transportation system in India outlining the related energy consumption, for the different transport modes, with consequent estimated emissions. These elements are essential for the preparation of a high-level strategic transport planning on the whole energy issue, to help India in the choices of most suitable transportation systems, according to the well-to-wheel analysis (WTW). Pursuing a WTW global index for India that takes into account both the energy and environmental aspects on a uniform basis is an important aim: it allows the best choices to be made as well as enabling the comparison between some of the most important powertrain and fuel options on the Indian market, the results are discussed from three different points of view: energy, environmental and economic impac
Pant hoot chorusing and social bonds in male chimpanzees
No full textVocal interactions, such as call exchanges or chorusing, are common behaviours in many animal species and their function has often been attributed to social bonding. However, few studies have investigated the effectiveness of vocalizations as bonding signals in comparison to other affiliative behaviours. We tested the hypothesis that male chimpanzee, Pan troglodytes schweinfurthii, pant hoot chorusing, a common behaviour in these primates, is a reliable but also flexible signal of affiliative relationships. The results of our study, conducted on the Kanyawara community of chimpanzees in Uganda, show that males were more likely to join in with the pant hoot of preferred long-term social partners to form a chorus. This supports the hypothesis that this behaviour is a good indicator of strong or long-term social bonds between male chimpanzees. However, our results also show that pant hoot chorusing reliably reflects short-term affiliations between males. For instance, male dyads were more likely to be involved in affiliative behaviours, such as reciprocated grooming, joint nonvocal displays and coalitions, on days when they chorused together, compared to days when they did not. This pattern applied to both preferred and neutral social partners. Moreover, on a short-term basis chorusing was a better indicator of other affiliative behaviours than grooming. We suggest that in male chimpanzees pant hoot choruses are efficient signals of short-term affiliative relationships. We conclude that potentially low-cost bonding behaviours such as coordinated vocal displays might be especially adaptive in highly fluid fission–fusion societies where grouping patterns are often unpredictable
Social and ecological correlates of long-distance pant hoot calls in male chimpanzees
No full textLong-distance calls have a variety of functions in different animal species. However, where multiple functions are proposed for a single long-distance call type, little is known about their relative importance. Chimpanzees are one species where several functions have been proposed for their long-distance call, the pant hoot. In this study, we investigated the effect of social factors, including the rank of the caller, party size, fission–fusion rates, and the presence of estrus females as well as ecological factors including the type of food consumed and travel time, on male chimpanzee (Pan troglodytes schweinfurthii) pant hooting, in order to identify the key correlates of this behavior. The wild male chimpanzees of the Kanyawara community, Uganda, produced more pant hoots on days when there were frequent changes in the male, but not female, composition of the focal’s party. This factor accounted for the largest amount of variation in pant hoot production, and we found that males were more likely to repeat a call prior to rather than after fusion with other males, suggesting that the calls facilitate fusion. Pant hoots therefore seem to play a pivotal role in regulating grouping dynamics in chimpanzees. Our study also shows that pant hooting was positively correlated with the rank of the caller, the presence of parous females in estrus, and the consumption of high-quality food, suggesting that pant hoots signal social status or social bonds when between-male competition is high. This study supports the view that pant hoots fulfill a complex social function
Improving K-Mean Clustering: A Comparative Study of Parallelized Version of Modified K-Mean Algorithm for Clustering of Satellite Images
No full textEfficient clustering of high-dimensional satellite image datasets remains a critical challenge, particularly due to the computational demands of spectral distance calculations, random centroid initialization, and sensitivity to outliers in conventional K-Mean algorithms. This study presents a comprehensive comparative analysis of eight parallelized variants of the K-means algorithm, designed to enhance clustering efficiency and reduce computational burden for large-scale satellite image analysis. The proposed parallelized implementations incorporate optimized centroid initialization for better starting point selection, a Dynamic K-mean sharp method to detect the outlier to improve cluster robustness, and a Nearest-Neighbor Iteration Calculation Reduction method to minimize redundant computations. These enhancements were applied to a test set of 114 global land cover data cubes, each comprising high-dimensional satellite images of size 3712*3712*16, and executed on multi-core CPU architecture to leverage extensive parallel processing capabilities. Performance was evaluated across three criteria: convergence speed (iterations), computational efficiency (execution time), and clustering accuracy (RMSE). The Parallelized Enhanced K-Mean (PEKM) method achieved the fastest convergence at 234 iterations and the lowest execution time of 4230 hours, while maintaining consistent RMSE values (0.0136) across all algorithm variants. These results demonstrate that targeted algorithmic optimizations, combined with effective parallelization strategies, can improve the practicality of K-means clustering for high dimensional satellites image analysis. This work underscores the potential of improving K-means clustering frameworks beyond hardware acceleration alone, offering scalable solutions good for large-scale unsupervised image classification tasks
Measurements of branching fraction ratios and CP-asymmetries in suppressed B- -> D(-> K+ pi(-))K- and B- -> D(-> K+ pi(-))pi(-) decays
Get PDFWe report the first reconstruction in hadron collisions of the suppressed decays B- -> D(-> K+ pi(-))K- and B- -> D(-> K+ pi(-))pi(-), sensitive to the Cabibbo-Kobayashi-Maskawa phase gamma, using data from 7 fb(-1) of integrated luminosity collected by the CDF II detector at the Tevatron collider. We reconstruct a signal for the B- -> D(-> K+ pi(-))K- suppressed mode with a significance of 3.2 standard deviations, and measure the ratios of the suppressed to favored branching fractions R(K) = [22.0 +/- 8.6(stat) +/- 2.6(syst)] x 10(-3), R+ (K) = [42.6 +/- 13.7(stat)] +/- 2.8(syst)] x 10(-3), R- (K) = [3.8 +/- 10.3(stat) +/- 2.7(syst)] x 10(-3) as well as the direct CP-violating asymmetry A(K) = -0.82 +/- 0,44(stat) +/- 0.09(syst) of this mode. Corresponding quantities for B- -> D(-> K+ pi(-))pi(-) decay are also reported
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