Equilibrium studies of ternary systems containing some selected transition metal ions, triazoles and aromatic carboxylic acids

Solution equilibria of the binary and ternary complex systems of the divalent transition metal ions Cu²⁺, Ni²⁺, Zn²⁺, and Co²⁺ with 1,2,4-triazole (TRZ), 3-mercapto-1,2,4-triazole (TRZSH), and 3-amino-1,2,4-triazole (TRZAM) and aromatic carboxylic acids (phthalic, anthranilic, salicylic, and 5-sulfosalicylic acid) have been studied pH-metrically at (25.0±0.1) °C, and a constant ionic strength I=1×10^?1 mol L^?1 NaNO₃ in an aqueous medium. The potentiometric titration curves show that binary and ternary complexes of these ligands are formed in solution. The stability constants of the different binary and ternary complexes formed were calculated on the basis of computer analysis of the titration data. The relative stability of the different ternary complex species is expressed in terms of Δ log K values, log X and R. S.% parameters. The effect of temperature of the medium on both the proton-ligand equilibria for TRZAM and phthalic acid and their metal-ligand equilibria with Cu²⁺, Ni²⁺, and Co²⁺ has been studied along with the corresponding thermodynamic parameters. The complexation behavior of ternary complexes is ascertained using conductivity measurements. In addition, the formation of ternary complexes in solution has been confirmed by using UV-visible spectrophotometry.     

TRACER RESPONSE IN PARTIALLY FRACTURED RESERVOIRS

There is considerable interest in the petroleum industry to characterize partially fractured reservoirs and to develop an increased understanding of the physics of fluid flow in these types of reservoirs. This is because fractured reservoirs have different behavior and there exist a large number of these reservoirs that are not fully developed. This paper presents a numerical simulation study that was performed to investigate the effect of rock properties on the tracer response in partially fractured reservoirs using a finite difference numerical simulator. These properties include fracture intensity, fracture porosity and matrix permeability. The functional relationships between these parameters and the calculated effective permeabilities are also investigated. Several images, each with different probability of fracture intensity, were generated randomly. Numerical simulations of single-phase tracer transport were then performed in each of the generated fractured models. Results show that the fracture intensity, fracture porosity and matrix permeability have a significant effect on the tracer response in naturally fractured reservoirs. Depending on the reservoir properties, the results also show that the flow in partially fractured reservoirs can be either matrix-dominated or fracture-dominated. The characteristics of each regime and the conditions for its occurrence are presented.     

Improved Beam Steering Method Using OAM Waves

Orbital Angular Momentum (OAM) is an intrinsic feature of electromagnetic waves which has recently found many applications in several areas in radio and optics. In this paper, we use OAM wave characteristics to present a simple method for beam steering over both elevation and azimuth planes. The design overcomes some limitations of traditional steering methods, such as limited dynamic range of steering, the design complexity, bulky size of the steering structure, the limited bandwidth of operation, and low gain. Based on OAM wave characteristics, the proposed steering method avoids design complexities by adopting a simple method for generating the OAM-carrying waves. The waves are generated by an array of Planar Circular Dipole (PCD) elements. These elements are designed to cover a wide bandwidth range between 3 and 30 GHz. The transmitting array shows an enhanced gain value from 8.5 dBi to almost 11.5 dBi at the broadside angle. Besides the enhanced PCD-based OAM generation, the novelty of the design lies in a new method of beam steering. Beam steering is then performed by controlling the electrical feeding of the PCD elements; the beam azimuthal location is managed by turning off some of the PCD elements, while the elevation is determined by changing the gradient phase of excitation for the turned-on PCD elements. Detailed analysis of the steering method is carried out by finding the mathematical model of the system and the generated waves. The performance has been verified through numerical simulators.     

Attitudes of Kuwaiti parents toward physical punishment of children

OBJECTIVE: The major aim was to describe parental attitudes to physical punishments and examine their sociodemographic correlates. A related aim was to assess the association of parents' own experience of physical punishment with attitudes to punishment of children. METHOD: A cross-sectional survey was conducted during the second week of December, 1996 in five general clinics covering the major administrative areas of Kuwait: 337 Kuwaiti mothers and fathers with at least one living child were contacted; 95% were successfully interviewed using a structured questionnaire. RESULTS: Eighty-six percent of parents agreed with physical punishment as a means of child disciplining. Agreement with punishment was higher in case of serious misbehaviors such as stealing (63%), sniffing glue and using drugs (77%). Multiple regression results showed that parent's lower level of education and Bedouin ethnicity were positively associated with agreement on physical punishment. Larger percentages of parents who had experienced physical punishments themselves agreed with such punishment to discipline their children, but this was not statistically significant. CONCLUSIONS: In recent years education has become widespread for both sexes. An inverse association between educational level and agreement on physical beating suggest that attitudes to this form of child disciplining are changing. Those with a Bedouin ethnic background still adhere more strictly to the traditional forms of child disciplining including physical beating. There is a need for conducting research on the possible negative psychosocial impacts of physical punishment in view of findings from other countries.     

Antioxidant and antithrombotic effects of green mussels (Perna canaliculus) in rats

In the past decade, the use of marine mussels as seafood is being more popular. They considered being a rich source of various nutritional bioactive compounds that aroused the scientific community's interest. This study investigated the antioxidant and the antithrombotic consequences on Sprague-Dawley male rats after adding dried New Zealand mussel Perna canaliculus in their diet. The biochemical, hematological and histopathological changes were also observed. Forty rats were divided into four groups according to the amount of dried mussels in their diet, in addition to a control group that consumed a basal diet only. Group 1 consumed 25% dried mussels in its basal diet; Group 2 consumed 35% dried mussels in its basal diet, and Group 3 was consumed 45% dried mussels in its basal diet. The biochemical parameters showed improvements in liver function. Interestingly, the lipid profile decreased, especially the low-density lipoprotein cholesterol (LDL-C) levels which were reduced significantly in Group 3 (p < .01). These observations were accompanied by a decrease in iron levels significantly as the amount of dried mussels increased (p < .01). Furthermore, the noticed changes in the hematological profile prove that there is an increase in antithrombotic activity. Dried mussels had potent antioxidant effects in the liver as shown by increased lipid peroxide (p < .05), reduced glutathione (p < .05), and glutathione peroxidase (GSH-Px; p < .05). Additionally, antioxidant activity in the kidney was shown to increase through GSH-Px activity (p < .01). In conclusion, these results indicate that consuming dried mussels resulted in improved biochemical and antioxidants activities and could be used as an antithrombotic agent.     

Poisonous Piperidine Plants and the Biodiversity of Norditerpenoid Alkaloids for Leads in Drug Discovery: Experimental Aspects

There are famous examples of simple (e.g., hemlock, Conium maculatum L.) and complex (e.g., opium poppy, Papaver somniferum L., Papaveraceae) piperidine-alkaloid-containing plants. Many of these are highly poisonous, whilst pepper is well-known gastronomically, and several substituted piperidine alkaloids are therapeutically beneficial as a function of dose and mode of action. This review covers the taxonomy of the genera Aconitum, Delphinium, and the controversial Consolida. As part of studying the biodiversity of norditerpenoid alkaloids (NDAS), the majority of which possess an N-ethyl group, we also quantified the fragment occurrence count in the SciFinder database for NDA skeletons. The wide range of NDA biodiversity is also captured in a review of over 100 recently reported isolated alkaloids. Ring A substitution at position 1 is important to determine the NDA skeleton conformation. In this overview of naturally occurring highly oxygenated NDAs from traditional Aconitum and Delphinium plants, consideration is given to functional effect and to real functional evidence. Their high potential biological activity makes them useful candidate molecules for further investigation as lead compounds in the development of selective drugs.     

Improving TLB performance on current chip multiprocessor architectures through demand‐driven superpaging

Translation Lookaside Buffers (TLBs) can play a critical role in improving the performance of emerging parallel workloads. Most current chip multiprocessor systems include multilevel TLBs and provide support for superpages both at the hardware and software level. Judicious use of superpages can significantly cut down the number of TLB misses and improve overall system performance. However, indiscriminate superpage allocation results in page fragmentation and increased application footprint, which often outweigh the benefits of reduced TLB misses. Previous research has explored policies for smart allocation of superpages from an operating system perspective. This paper presents a compiler‐based strategy for automatic and profitable memory allocation via superpages. A significant advantage of a compiler‐based approach is the availability of data‐reuse information within an application. Our strategy employs data‐locality analysis to estimate the TLB demands for both single‐threaded and multi‐threaded programs and uses this metric to apply selective superpage allocation. Apart from its obvious utility in improving TLB performance, this strategy can be used to improve the effectiveness of certain data‐layout transformations and can be a useful tool in benchmarking and automatic performance tuning. We demonstrate the effectiveness of this strategy with experiments on three multicore platforms on a workload that contains both sequential and parallel applications. Copyright © 2012 John Wiley & Sons, Ltd.     

A dynamic cross-layer routing protocol for Mobile Ad hoc Networks

A new cross-layer routing protocol, named Dynamic Packet Guidance (DPG), is introduced for Mobile Ad hoc Networks (MANETs). Simulation results show that DPG is quite useful for usage in dense networks of mobile nodes, with medium-to-high speeds, and low-to-medium load. In these scenarios, DPG provides a superior performance compared to several well-known ad hoc routing protocols. The low end-to-end delay and smaller overhead that DPG achieves in such scenarios positively impacts the scalability of MANETs and reduces the energy requirements of nodes in such networks. DPG also shows immunity to failing nodes, as it operates consistently almost independently of failing nodes up to a certain ratio.     

Modulation of PTPN2/22 Function by Spermidine in CRISPR-Cas9-Edited T-Cells Associated with Crohn’s Disease and Rheumatoid Arthritis

Crohn’s Disease (CD) and Rheumatoid Arthritis (RA) share some single nucleotide polymorphisms (SNPs) in protein tyrosine phosphatase non-receptor types 2 and 22 (PTPN2/22). Recently, we reported that clinical samples from CD and RA patients associated with PTPN2:rs478582 or PTPN22:rs2476601 genotypes were linked to overactive immune response and exacerbation of inflammation. Here, we investigated in vitro the effects of these SNPs in Jurkat T-cells using CRISPR-Cas9. All cells were evaluated for PTPN22/22 loss of function and effects on cell response. We measured gene expression via RT-qPCR and cytokines by ELISA. We also measured cell proliferation using a BrdU labeling proliferation ELISA, and T-cell activation using CD-25 fluorescent immunostaining. In PTPN2 SNP-edited cells, PTPN2 expression decreased by 3.2-fold, and proliferation increased by 10.2-fold compared to control. Likewise, expression of PTPN22 decreased by 2.4-fold and proliferation increased by 8.4-fold in PTPN22 SNP-edited cells. IFN-γ and TNF-α secretions increased in both edited cell lines. CD25 expression (cell activation) was 80.32% in PTPN2 SNP-edited cells and 85.82% in PTPN22 SNP-edited cells compared to 70.48% in unedited Jurkat T-cells. Treatment of PTPN2 and PTPN22-edited cells with a maximum 20 μM spermidine restored PTPN2/22 expression and cell response including cell proliferation, activation, and cytokines secretion. Most importantly, the effect of spermidine on edited cells restored normal expression and secretion of IFN-γ and TNF-α. The data clearly demonstrated that edited SNPs in PTPN2 or PTPN22 were associated with reduced gene expression, which resulted in an increase in cell proliferation and activation and overactive immune response. The data validated our earlier observations in CD and RA clinical samples. Surprisingly, spermidine restored PTPN2/22 expression in edited Jurkat T-cells and the consequent beneficial effect on cell response and inflammation. The study supports the use of polyamines dietary supplements for management of CD and in RA patients.     

Effective Hybrid Content-Based Collaborative Filtering Approach for Requirements Engineering

Requirements engineering (RE) is among the most valuable and critical processes in software development. The quality of this process significantly affects the success of a software project. An important step in RE is requirements elicitation, which involves collecting project-related requirements from different sources. Repositories of reusable requirements are typically important sources of an increasing number of reusable software requirements. However, the process of searching such repositories to collect valuable project-related requirements is time-consuming and difficult to perform accurately. Recommender systems have been widely recognized as an effective solution to such problem. Accordingly, this study proposes an effective hybrid content-based collaborative filtering recommendation approach. The proposed approach will support project stakeholders in mitigating the risk of missing requirements during requirements elicitation by identifying related requirements from software requirement repositories. The experimental results on the RALIC dataset demonstrate that the proposed approach considerably outperforms baseline collaborative filtering-based recommendation methods in terms of prediction accuracy and coverage in addition to mitigating the data sparsity and cold-start item problems.