Attack containment in mobile ad-hoc networks through fair distribution of processing resources

Due to frequent joining and leaving of nodes and better performance, use of flooding algorithms is always proffered in Mobile Ad-hoc Networks (MANETs). A single query transmitted by a node can be received by hundreds of nodes at 3rd or 4th hop. But it is also fact that flooding algorithms provide an opportunity to attackers for launching query flooding attacks. On one side these query flooding attacks results in wastage of valuable processing resources and on the other side they cause in starvation and delay at legitimate user’s end. To solve this problem we proposed attack containment techniques by providing a fair share of processing resources to every node. Fair distribution is achieved by designing different query distribution techniques based on mathematical models. Results obtained through network simulator 2 prove that the proposed solution is resilient against various types of flooding attacks.     

A Transformed Coordinates Shallow Water Model for the Head of the Bay of Bengal Using Boundary-Fitted Curvilinear Grids

The Bay of Bengal is surrounded by coastline except to the south, where there is open sea. The coastline bends most sharply along the coast of Bangladesh, and there are many small and large islands in the offshore region there. In order to incorporate the island boundaries and the curved coastline properly, in any numerical scheme it is often necessary to consider a very fine grid resolution along the coastal belts whereas this is unnecessary away from the coasts. However, a very fine resolution involves more memory and more CPU time in the numerical solution process, and invites numerical instability. On the other hand, boundary-fitted curvilinear grids in hydrodynamic models for coastal seas, bays and estuaries not only fit to the coastline but also render the finite difference schemes simpler and more accurate. In this article, the boundary-fitted curvilinear grids for the model represent the complete boundary of the area considered by four curves defined by four functions, and the four boundaries of two of the larger islands are then represented approximately by two general functions. An appropriate independent coordinate transformation maps the curvilinear physical area to a square domain, and each island boundary is transformed to a rectangle within this square domain. The vertically integrated shallow water equations are transformed to the new space domain, and solved by a regular explicit finite difference scheme. The model is applied to compute the water levels due to astronomical tides, and also the water levels due to surges associated with tropical storms that hit the coast of Bangladesh.     

Modified nano supported catalyst for selective catalytic hydrogenation of edible oils

We report an interesting finding that the catalytic performance of supported Ni/γ-Al₂O₃ catalyst towards selective catalytic hydrogenation of edible oils can be greatly enhanced by pretreatment of the γ-Al₂O₃ support before catalyst preparation. Calcination of Al₂O₃ at appropriate temperatures results in the highly dispersive nano Ni/γ-Al₂O₃ catalyst and thus improves the catalytic performance. Catalyst sample of improved physical properties prepared by modified procedure using γ-Al₂O₃ as support was characterized using powder XRD, SEM, BET, FTIR, Particle size analyzer, CO-chemisorption, and TPR studies. These studies indicate that support pretreatment results in enhancing catalyst dispersion with increase in Ni loadings. Clearly the effect of surface area and particle size of the catalyst coupled with surface properties and method of catalyst preparation on the saturated fats content of the foods like margarines prevails.     

Correction to: A review of machine learning-based human activity recognition for diverse applications

Neural Computing and Applications -     

Phase slip solutions in magnetically modulated Taylor–Couette flow

We numerically investigate Taylor–Couette flow in a wide-gap configuration, with \({r_i/r_o=1/2}\), the inner cylinder rotating, and the outer cylinder stationary. The fluid is taken to be electrically conducting, and a magnetic field of the form \({B_z\approx(1 + \cos(2\pi z/z_0))/2}\) is externally imposed, where the wavelength \({z_0=50(r_o-r_i)}\). Taylor vortices form where the field is weak, but not where it is strong. As the Reynolds number measuring the rotation rate is increased, the initial onset of vortices involves phase slip events, whereby pairs of Taylor vortices are periodically formed and then drift outward, away from the midplane where \({B_z=0}\). Subsequent bifurcations lead to a variety of other solutions, including ones both symmetric and asymmetric about the midplane. For even larger Reynolds numbers, a different type of phase slip arises, in which vortices form at the outer edges of the pattern and drift inward, disappearing abruptly at a certain point. These solutions can also be symmetric or asymmetric about the midplane and co-exist at the same Reynolds number. Many of the dynamics of these phase slip solutions are qualitatively similar to previous results in geometrically ramped Taylor–Couette flows.     

Safety studies on intravenous infusion of a potent angiogenesis inhibitor: taurocholate-conjugated low molecular weight heparin derivative LHT7 in preclinical models

Context: As a class of angiogenesis inhibitors, heparin conjugates have shown significant effectiveness in several studies.

Objectives: The purpose of our current study is to evaluate the effectiveness and safety of infusing the conjugate of low molecular weight heparin and taurocholate (LHT7), which has been developed as a potent angiogenesis inhibitor.

Methods: To evaluate its safety, the method of intravenous infusion was compared with its i.v. bolus administration. Intravenous infusion was administered at a rate of 400?μl/min/kg of body weight for 30?min. Pharmacokinetic (PK) analysis, organ accumulation, and plasma concentration profiles of LHT7 were measured. The anticancer effect of LHT7 was evaluated in murine and human xenograft models, and preclinical studies were performed in SD rats and beagle dogs.

Results: The results of the PK studies showed reduced organ accumulation in mice and the AUC_(0–96?h) (area under the curve) was increased up to 1485?±?125?h?×?μg/ml. The efficacy, at dose 1?mg/kg/2 d was higher for i.v. infusion than for i.v. bolus administration in both murine and human cancer models. The preclinical studies showed the safety dose of LHT7 is less than 20?mg/kg in SD rats and in the next safety analysis in beagle dogs showed that there were no organ-specific adverse effects in higher doses, such as, 12?mg/kg. LHT7 showed sustained effects with minimized adverse events when administered through i.v. infusion.

Conclusions: LHT7 (i.v. infusion) could be safely used for further clinical development as a multi-targeting anti-angiogenic agent.     

Secure architecture to circumvent collision using RSSI measurement in WSN: a cross layer design approach

Multimedia Tools and Applications - ‘Wireless sensor networks’ (WSNs) follow layered architecture for the fruitful and reliable working of distributed WSNs. The region of WSN is...     

Studies on uptake and distribution of antibiotics in red cabbage

A large source of antibiotic active compounds and resistant bacteria is livestock waste, distributed as fertilizer on fields, used for vegetable cultivation. Frequently consumed vegetable, contaminated by low levels of antibiotics, may contribute to the development of bacterial antibiotic resistance. The objective of this work was to estimate the possible role of red cabbage as reservoir and carrier of antibiotic contaminants into the food chain. Red cabbage was exposed to antibiotics in hydroponic cultures and farming conditions. Enrofloxacin (ENR), chlortetracycline (CTC), monensin (MON) and amoxicillin (AMO) were separately added to nutrient solutions. Analysed by sequential extraction and LC–MS/MS methods, the plants revealed a remarkable uptake of CTC and in particular ENR (old leaves 0.22 mg/kg fresh weight (fw) CTC, 6.0 mg/kg fw ENR; roots up to 215.0 mg/kg fw CTC, 14.6 mg/kg fw ENR). The uptake of MON was significantly lower and AMO was not detectable. Red cabbage was also grown on manure-fertilized plots. The pig manure contained defined amounts of CTC and ENR (50 and 150 mg/kg). At harvest the edible parts of cabbage had between 9.2 to 16.9 µg/kg fw ENR, while there was no evidence obtained for the uptake of CTC. Finally, production steps of canned red cabbage were examined for carry over effects. Traces of tetracycline (16.4–19.2 µg/kg fw) were detected in supplies of freshly harvested vegetable, grown conventionally, but not in the marketable final product.     

A Rational Insight into the Effect of Dimethyl Sulfoxide on TNF-α Activity

Direct inhibition of tumor necrosis factor-alpha (TNF-α) action is considered a promising way to prevent or treat TNF-α-associated diseases. The trimeric form of TNF-α binds to its receptor (TNFR) and activates the downstream signaling pathway. The interaction of TNF-α with molecular-grade dimethyl sulfoxide (DMSO) in an equal volumetric ratio renders TNF-α inert, in this state, TNF-α fails to activate TNFR. Here, we aimed to examine the inhibition of TNF-α function by various concentrations of DMSO. Its higher concentration led to stronger attenuation of TNF-α-induced cytokine secretion by fibroblasts, and of their death. We found that this inhibition was mediated by a perturbation in the formation of the functional TNF-α trimer. Molecular dynamics simulations revealed a transient interaction between DMSO molecules and the central hydrophobic cavity of the TNF-α homodimer, indicating that a brief interaction of DMSO with the TNF-α homodimer may disrupt the formation of the functional homotrimer. We also found that the sensitizing effect of actinomycin D on TNF-α-induced cell death depends upon the timing of these treatments and on the cell type. This study will help to select an appropriate concentration of DMSO as a working solvent for the screening of water-insoluble TNF-α inhibitors.     

Synthesis and characterization of uniform fine particles of copper oxalate

Copper oxalate particles were synthesized in various shapes and sizes by mixing appropriate volumes of known concentration of oxalic acid and copper nitrate at 25 and 85 °C. Temperature and reactants concentration had significant effect on the morphology of the precipitated particles and therefore extensive optimizations of the experimental parameters were carried out in order to obtain maximum uniformity in particles' morphological features. Selected batch of the copper oxalate particles was characterized by various physical methods.