Antioxidant and anticancer activities of 8-hydroxypsoralen isolated from wampee [Clausena lansium (Lour.) Skeels] peel

Fruits of wampee [Clausena lansium (Lour.) Skeels] contain a significant amount of coumarins with many health benefits. The activity-guided separation of an ethyl acetate-soluble fraction on a polyamide column followed by silica gel column and high performance liquid chromatography (HPLC) preparation afforded a pure compound, which was identified to be 8-hydroxypsoralen based on the ¹H, ¹³C NMR (nuclear magnetic resonance), and ESI-MS (electrospray ionisation mass spectrometric) analysis. This isolate exhibited good scavenging activities against DPPH radical and superoxide anion as well as significant reducing power. It also showed potent proliferation inhibitory activity against human hepatocellular liver carcinoma cell line (HepG2), human lung adenocarcinoma epithelial cell line (A549) and human cervical carcinoma cell line (HELA). This is the first report on the antioxidant and cytotoxic properties of C. lansium fruit extract. The food and pharmaceutical industry could be benefited by the usage of this extract containing this constituent.     

Development of high temperature material for cellular ceramic regenerative storage heater

Ceramic Regenerative Storage Heater (RSH) is the preferable solution to provide clean hot air in Hypersonic Wind Tunnel (HWT) and Scramjet Test facilities to prevent the liquefaction of air during expansion in the high Mach number nozzles. Selection of the heater storage material for such operational requirements is a challenging task. As per the theoretical background; alumina, zirconia or mullite compositions have the capability to withstand at such high operating conditions. In the current study, a series of experiments were carried out to estimate the thermal characteristics of the material. This paper highlights the simplified approach by combining theoretical and experimental methods for economic (reduced time and cost) selection process of high temperature material. The desired material must possess good thermal shock resistance and low dust generation characteristics. Al₂O₃ and SiO₂ based matrix composition fused in a transcrystalline phase exhibits significant improvement on the overall material integrity. Several Al₂O₃ and SiO₂ matrix compositions were examined and the final matrix composite ratio of 90% of Al₂O₃ and 10% of SiO₂ is considered as the desired candidate material. The ceramic matrix was sintered at a temperature of 2123?K, under the specific pressure of 1400?kg/cm² for a period of 2?h, at a heating rate of 3.5?°C/min. The results of the thermal shock tests on various samples are presented. To improve the anti-dust characteristics, the final samples were coated with fine particles (5?µm) of Al₂O₃ and SiO₂ matrix. Based on the experimental evaluation, Al₂O₃ and SiO₂ fused matrix composition found to be meeting all the requirements of high temperature storage material.     

Advanced process modeling at the BCL smelter: Improving economic and environmental performance

Since 1973 Bamangwato Concessions Limited (BCL) has operated a nickel-copper smelter in Selebi-Phikwe, Botswana. The smelter treats concentrates from local mines and various custom feed concentrates. The nickel throughput capacity of this smelter is constrained by a low nickel feed grade in its primary BCL concentrate. BCL contracted Xstrata Process Support (XPS) to assist in identifying key economic drivers to maximize revenue-generating opportunities. After the disclosure of essential BCL plant performance data XPS developed and utilized advanced metallurgical modeling techniques to identify production bottlenecks, calculate Ni, Cu, and Co recoveries, manage the slag volumes, increase the custom feed capacity, and perform various feasibility analyses for key unit process operations in the BCL smelter. The methodology for developing the process model and its application in contributing to the economic bottom line are outlined in this paper.     

Optical properties and surface morphology of near infrared multilayer antireflection coatings

Theoretical and experimental studies on multilayer antireflection (AR) coatings useful in the near infrared region, covering 1200 to 2000 nm are carried out, in which the relative merits and demerits of using a low refractive index magnesium fluoride (MgF₂), along with a high refractive index Substance H2 (Sub2) material of E. Merck, in comparison to silicon dioxide (SiO₂) and Sub2, are specifically investigated. It is seen that MgF₂ together with Sub2 produces wider band antireflection coatings, with lower ripple and integrated reflection loss (IRL), R^*, whereas SiO₂/Sub2 combination produces AR coatings with medium spectral coverage, and the coatings are free of structural defects, which in turn are highly durable against adverse environmental conditions.     

Clustering effects on discontinuous gold film NanoCells

Reproducible negative differential resistance (NDR)-like switching behavior is observed in NanoCells. This behavior is attributed to the formation of filaments and clusters between the discontinuous gold films. Control experiments are performed by self-assembly of insulating molecules between the gold islands and conducting molecules on these islands. Additional control experiments are performed by removing the filaments and clusters between islands using a piranha bath. The results are consistent with theoretical predictions and extend the domain of molecular electronics based in organic molecules to include nanosized clusters as active units. This facilitates a scenario where synthetically accessible organic molecules, with defined characteristics, can be adjusted by metallic nanoclusters as an in situ fine-tuning element, able to compensate for the lack of addressing in the nanosize regime.     

An Efficient Delay Tolerance and Cost-Effective Secure NFV Enabled Multi-casting in Mobile Edge Cloud Networks

The mobile edge cloud has developed as the main platform to offer low latency network services from the edge of networks for stringent delay necessities of mobile applications. In mobile edge cloud networks, network functions virtualization (NFV) creates the frameworks for building up a new dynamic resource management framework structure to effectively utilize network resources. Delay tolerance NFV-enabled multicast request admissions in a mobile edge-cloud network are explored in this paper to limit request admission delays or maximizing system performance for a group of requests arriving individually. At first, for the cost reduction issue of a single NFV-empowered multicast request admission, the admission cost of each multicast request is assessed, and the Support based graph is constructed. Here, the multicast requests are prioritized dependent on their admission cost. Subsequently, trust and the delay-based local gradient are assessed for the prioritized multicast requests. At long last, delay tolerance NFV multicasting is accomplished by successful (First Come First Serve) FCFS queuing reliant on the assessed local gradient of requests. When compared to existing approaches, the exploratory results show that the proposed methodology is superior in terms of throughput, admission cost, and running time.

     

Controlled release tablet formulation containing natural Δ9-tetrahydrocannabinol

Cannabinoids are increasingly being used in the treatment of chemotherapy-induced nausea and vomiting (CINV) because of their action on the cannabinoid receptors, CB1 and CB2. The currently marketed capsule formulations (sesame oil based and crystalline powder) are required to be administered frequently to maintain therapeutic levels, which leads to non-compliance. In the present study, oral controlled release tablet formulations of Δ⁹-tetrahydrocannabinol (THC) were prepared using the lipids Precirol® and Compritol®. Release profiles using THC-lipid matrices and/or with the lipids in the external phase (blend) were evaluated. The effect of directly compressible diluents lactose mixture (Ludipress®), dicalcium phosphate anhydrous (Emcompress®) and microcrystalline cellulose (Avicel® 102) on tablet characteristics and in vitro drug release was also investigated. Further, in vitro THC release in the presence of a lipase inhibitor, Pluronic® F68, was also studied. A 24 h zero-order THC release profile was obtained with a combination of Precirol® and Compritol® in the compression blend. Addition of Pluronic® F68 did not alter THC release in vitro. These optimized tablets were chemically and physically stable for 3 months, the last time point tested, at 25?°C/60% RH. The overall results demonstrate the feasibility of preparing oral THC tablets for once a day administration which can improve CINV management.