Prevalence and public health significance of aluminum residues in milk and some dairy products

Sixty random samples of bulk farm milk, market milk, locally manufactured processed cheese, and milk powder were collected to be analyzed for aluminum (Al) concentration using graphite furnace atomic absorption spectrometry (GFAAS). The results were compared with provisional acceptable permissible limits (PAPLs). The maximum estimated dietary intake (MEDI) of Al for the examined samples was calculated. In addition, an experimental study was conducted to determine the possible leaching of Al from cookware in milk during boiling. The obtained results showed that Al concentration in examined bulk farm milk samples was found to be negligible. In contrast, market milk revealed higher concentration, 65.0% of the examined samples were above the PAPLs. The results revealed significant difference of Al concentration among them. The Al levels in processed cheese wrapped in Al foil were significantly higher than those found in samples packed in glass containers with a significant difference of Al concentration between them. Also, 20% of the examined milk powder samples exceeded the PAPLs (0.01 to 0.4 mg/kg). The MEDI for Al in bulk farm milk, control market milk, market milk boiled in Al cookware, market milk boiled in stainless-steel cookware, processed cheese wrapped in Al foil, processed cheese packed in glass containers, and milk powder were calculated as 3.0%, 61.0%, 63.0%, 61.0%, 428.0%, 220.0%, and 166.0% from "PTDI," respectively. The results of the experimental study showed no marked significant differences of Al concentration between market milk (control group) and those boiled in Al cookware, as well as to those boiled in stainless-steel cookware. PRACTICAL APPLICATION: The results of the present study indicate that Al level in milk kept in Al containers and dairy products packed in Al foil is beyond the permissible limits, suggesting health hazard. Therefore, all milk cans should be constructed of stainless steel, prevent the entrance of tap water into milk, and the processed cheese should be packed in glass containers and not wrapped in Al foil. Leaching of Al increased to a significant percent more during storage than during boiling, so milk should be kept in stainless steel or glass containers in the refrigerator.     

Opportunistic interference alignment for three‐tier partially connected heterogeneous networks

With the expected increase in the number of connected devices, heterogeneous networks (HetNets) technology has gained great attention in next generation wireless networks. The deployment of such low power nodes in the same geographical area and using the same allocated frequency introduces significant interference among different nodes in the network. In this paper, we propose a two‐stage opportunistic interference alignment (OIA) scheme for the three‐tier downlink HetNet that targets user scheduling along with mitigating intertier and intratier interference signals. Two cascaded precoding matrices as well as two cascaded postcoding matrices are used to perform the two‐stage interference alignment (IA) operation. The outer precoding/postcoding matrix pair are designed using the rank‐constrained rank minimization (RCRM) to minimize the interference among the users associated to the same tier. Simulations show that the proposed scheme outperforms other conventional schemes in terms of the sum rate and the sum achieved degrees of freedom (DoF).     

LRV: A Tool for Academic Text Visualization to Support the Literature Review Process

Text visualization is concerned with the representation of text in a graphical form to facilitate comprehension of large textual data. Its aim is to improve the ability to understand and utilize the wealth of text-based information available. An essential task in any scientific research is the study and review of previous works in the specified domain, a process that is referred to as the literature survey process. This process involves the identification of prior work and evaluating its relevance to the research question. With the enormous number of published studies available online in digital form, this becomes a cumbersome task for the researcher. This paper presents the design and implementation of a tool that aims to facilitate this process by identifying relevant work and suggesting clusters of articles by conceptual modeling, thus providing different options that enable the researcher to visualize a large number of articles in a graphical easy-to-analyze form. The tool helps the researcher in analyzing and synthesizing the literature and building a conceptual understanding of the designated research area. The evaluation of the tool shows that researchers have found it useful and that it supported the process of relevant work analysis given a specific research question, and 70% of the evaluators of the tool found it very useful.     

Groundwater flow model for the Nubian aquifer in the Khartoum area,Sudan

The interbedded sands and mudstones of the Nubian aquifer provide Khartoum city with more than 43% of its drinking water. The recharge is mainly from the Nile system into semi-confined to confined conditions at depths from 10 m close to the Nile to more than 60 m away from the river. The paper briefly discusses the hydrogeology of the area and the modeling undertaken, which indicates that significant groundwater depletion will be exacerbated over the next 26 years if the present extraction rate continues unchecked. It is recommended that sensitivity studies are undertaken with continuous monitoring to create a computer database, such that appropriate levels of abstraction can be maintained.     

Evaluating Algibon adsorbent and adsorption kinetics for launderette water treatment: towards sustainable water management

Grey water from commercial laundry facility was used for treatment to substitute the conventional water sources. Algibon, A800 derived from mesoporous alginic acid and Starbon S300, carbonaceous mesoporous polysaccharide‐derived materials, silica gel (SG) and activated carbon (AC) were used for the treatment of wastewater. The optimum adsorbent dosing and pH value for each adsorption system are defined. The adsorption efficiency are in the order of A800 > SG > AC > S300 and the removal rate reached to 91% when A800 was used. Furthermore, the reaction followed the second‐order kinetic model and the rate constant is high when A800 adsorbent is applied.     

Experimental and modelling study of twin cells with latent heat storage walls

An experimental and numerical simulation study of the application of phase change materials (PCMs) in building components is presented for thermal management of a passive solar test-room. The experimental study was conducted in an outdoor test cell constituted of two small rooms separated with a wall containing PCM. A specific wall made of hollow glass bricks filled with PCM was studied. Three PCMs were tested: fatty acid, paraffin, and salt hydrate whose melting temperatures are 21 °C, 25 °C and 27.5 °C respectively.Indoor and outdoor temperatures were measured with thermocouples. Ten fluxmeters located at the centre of each wall allowed us to measure the heat fluxes across the walls. Tests were carried out in real climatic conditions.A one-dimensional numerical model has been developed to simulate the transient heat transfer process in the walls. Reasonable agreement between the simulation and the experimental results was observed.     

DETERMINATION OF CINACALCET HYDROCHLORIDE BY CAPILLARY ELECTROPHORESIS WITH PHOTODIODE ARRAY DETECTION

This article reports a validated stability-indicating capillary electrophoresis method using a photodiode array detector at 220 nm for the determination of cinacalcet hydrochloride. The best electrophoretic separation between the analyte and internal standard (lamotrigine) was achieved within 5 min in a deactivated fused silica capillary (55 cm effective length × 75 µm internal diameter) maintained at 24°C using a background electrolyte solution consisted of phosphate buffer (50 mM, pH 6.4):methanol (95:5, v/v) at a separation voltage of 30 kV. The linear range of the method was 0.5–30 µg/mL (r = 0.9999) with limits of detection and quantitation of 0.1 and 0.5 µg/mL, respectively. The assay precision and accuracy were favorable as the relative standard deviations did not exceed 1.09%, and the recovery values were 98.99–100.33 ± 0.19–1.09%. The induced degradation products, when any, did not interfere with the detection of analyte. The proposed method was successfully applied for the determination of cinacalcet hydrochloride in bulk and pharmaceutical formulations; the percentage recovery values were 98.16–102.00 ± 0.24–1.08%. The results demonstrated the value of the method.     

Application of fractional factorial design for green synthesis of cyano-modified silica nanoparticles: Chemometrics and multifarious response optimization

Cyano-functionalized spherical silica nanoparticles (SNPs) were synthesized via Stöber method. A 2?^k-p_IV–fractional factorial design (2^k-p_IV–FFD) was used to smartly prepare monodispersed evenly distributed SNPs. Six factors were considered; concentrations of tetraethylorthosilicate (TEOS), 3-Cyanopropyltriethoxysilane (CPTS), water, and ammonia, reaction time (RT) and stirring time (ST). Two responses; particle size (PS, measured by SEM) and particle-size distribution (PSD, calculated as standard deviation, ±SD) were measured. Control charts were used to decide on impacts of linear and two-way interactions on both responses. Derringer’s function was used to consolidate these multifarious responses into a uniform execution characteristic. Both screening and optimization were always accompanied by ANOVA testing at a 95.0% confidence interval (CI). The ideal synthetic conditions were obtained from the composite desirability plots. Cyano-functionalized SNPs with an average PS of 474.04?±?86.71?nm were produced. Raman spectroscopy and FTIR were used to confirm the functionalization process. Thermogravimetric analysis (TGA) was used to evaluate the thermal behavior of synthesized particles.     

Dictatorial Transaction Processing: Atomic Commitment Without Veto Right

The current standard in governing distributed transaction termination is the so-called Two-Phase Commit protocol (2PC). The first phase of 2PC is a voting phase, where the participants in the transaction are given an ultimate right to abort that transaction. Giving up that veto right from all participants reduces the overhead of the atomic commitment protocol but also imposes some restrictions on the concurrency control and recovery protocols employed by the participants in the transaction.This paper gives, for the first time, a precise abstract specification of the Dictatorial Atomic Commitment (DAC) problem, resulting from removing veto rights from the traditional Atomic Commitment (AC) problem. We characterize transactional systems that are compatible with that specification in terms of necessary and sufficient conditions on concurrency control and recovery protocols, and discuss the practical impacts of those conditions. From this study, we capitalize on existing protocols that solve the DAC problem, and propose a new protocol that broadens the applicability of dictatorial transaction processing in order to meet the requirements of today's distributed environments. We point out interesting performance tradeoffs, and describe the implementation of our protocol in the context of current transactional standards, initially designed with 2PC in mind.