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Open access

Ahmed A. Salem and Ibrahim Sadek Seddiek

Abstract

The world is facing the challenge of continuously increasing energy consumption. At the same time, the energy resources are getting scarcer. Despite a sudden significant drop of fuel prices worldwide, research activities that focus on reducing the dependence on fossil fuels as a traditional source of energy still have the preference in the field of shipping industry. The use of clean and renewable energies, such as solar energy for instance, is proposed as a method to improve the ship efficiency. Ships can get the benefits from solar energy due to the fact that most of their upper decks are always exposed to the Sun, especially in sunny water regions. The present paper discusses the effectiveness and challenges of installing solar panels for auxiliary power production on board a ship. As a case study, the research evaluates both economic and environmental benefits resulting from implementing such concept aboard a research vessel.

Open access

Ramadan A. Hassanein, Ehab A. Salem and Ahmed A. Zahran

Abstract

This study was performed to explore the efficacy of combining more than one postharvest treatment in maintaining some quality attributes and reducing fungal pathogenicity in cold-stored guava fruits. The investigated postharvest treatments included the control, CaCl2 (4%), lemongrass oil (2 dm3 kg−1), gamma (γ) irradiation (0.2, 0.4 and 0.6 kGy), 0.4 kGy γ irradiation + CaCl2 (4%), and 0.4 kGy γ irradiation + lemongrass oil (2 dm3 kg−1). The studied physiochemical attributes included weight loss, decay percentage, fruit firmness, total soluble solids (TSS), titratable acidity (TA), and vitamin C content. Different fungal species were also isolated from decayed fruits and were identified as Alternaria alternata, Alternaria solani, Aspergillus niger, Botrytis cinerea, Fusarium solani and Rhizopus stolonifer. The severity of infection for the different fungi was determined, and an in vitro antifungal assay was conducted for lemongrass oil. All the investigated treatments generally reduced decay and water loss percentages, and controlled TSS, TA and vitamin C decrements that occurred during cold storage. On the other hand, higher irradiation doses generally increased fruit softness, and the 0.4 kGy γ dose did not contribute to the overall fruit quality when coupled with CaCl2 and lemongrass oil, compared to CaCl2 and lemongrass oil treatments alone.

Open access

Ahmed Salem, Pascal Berrang, Mathias Humbert and Michael Backes

Abstract

The decreasing costs of molecular profiling have fueled the biomedical research community with a plethora of new types of biomedical data, enabling a breakthrough towards more precise and personalized medicine. Naturally, the increasing availability of data also enables physicians to compare patients’ data and treatments easily and to find similar patients in order to propose the optimal therapy. Such similar patient queries (SPQs) are of utmost importance to medical practice and will be relied upon in future health information exchange systems. While privacy-preserving solutions have been previously studied, those are limited to genomic data, ignoring the different newly available types of biomedical data.

In this paper, we propose new cryptographic techniques for finding similar patients in a privacy-preserving manner with various types of biomedical data, including genomic, epigenomic and transcriptomic data as well as their combination. We design protocols for two of the most common similarity metrics in biomedicine: the Euclidean distance and Pearson correlation coefficient. Moreover, unlike previous approaches, we account for the fact that certain locations contribute differently to a given disease or phenotype by allowing to limit the query to the relevant locations and to assign them different weights. Our protocols are specifically designed to be highly efficient in terms of communication and bandwidth, requiring only one or two rounds of communication and thus enabling scalable parallel queries. We rigorously prove our protocols to be secure based on cryptographic games and instantiate our technique with three of the most important types of biomedical data – namely DNA, microRNA expression, and DNA methylation. Our experimental results show that our protocols can compute a similarity query over a typical number of positions against a database of 1,000 patients in a few seconds. Finally, we propose and formalize strategies to mitigate the threat of malicious users or hospitals.

Open access

Tarek A. Morsy, Ahmed E. Kholif, Sobhy M. Kholif, Abdelkader M. Kholif, Xuezhao Sun and Abdelfattah Z. M. Salem

Abstract

The aim of this study was to evaluate the effect of two commercial enzyme products on milk production in Egyptian buffaloes. Twenty-one lactating buffaloes (570±15 kg BW) were divided into three groups (n=7) in a randomized block design for four months. Buffaloes were fed a total mixed ration containing 60% forage [rice straw and berseem hay (Trifolium alexandrinum)] and 40% concentrates with either no enzymes added (Control) or an addition of 40 g of Veta-Zyme Plus® (VET) or 40 g of Tomoko® (TOM ) enzyme product per day for each buffalo. Enzyme addition did not affect feed intake (P>0.05), but increased the digestibility of nutrients (P<0.05) and serum glucose concentration (P=0.011). Furthermore, the addition of VET increased milk (P=0.017) and fat corrected milk (P=0.021) yields, fat content (P=0.045), total unsaturated fatty acid (P=0.045) and total conjugated linoleic acid (P=0.031) contents in milk and decreased the content of total saturated fatty acids (P=0.046), while the addition of TOM increased milk total protein (P=0.023) and true protein (P=0.031) contents. The two enzyme products both resulted in higher concentrations of lysine (P=0.045) and total essential amino acids (P=0.036) in milk. It was concluded that addition of commercial fibrolytic enzyme products (i.e. Veta-Zyme Plus® and Tomoko®) to the diet of early lactating buffaloes enhanced nutrient digestibility and milk production and quality.