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Heavy metals in food can pose significant health risks, necessitating regular monitoring and assessment of their concentrations in commonly consumed foods. This study aims to assess the levels of essential and heavy metals and conduct health risk assessments in peanuts and date palms. Using wet acid digestion, the concentrations of heavy metals: iron (Fe), zinc (Zn), copper (Cu), arsenic (As), lead (Pb), and chromium (Cr) were measured in six each sample of peanuts and date palms, via Flame Atomic Absorption Spectroscopy (FAAS). To assess the health risks for adult males and females, the study calculated the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and incremental lifetime cancer risk (ILCR) based on Maximum Recommended Daily Intake (MRDI) of each metal. The average concentrations of heavy metals in peanuts were: Fe 12.6 ± 0.54, Zn 5.3 ± 0.1, Cu 3.53 ± 0.33, As 0.001 ± 0.0, Pb 0.01 ± 0.0, and Cr 0.02 ± 0.0 in mg/kg. For date palms, the average concentrations were: Fe 40.23 ± 2.5, Zn 48.31 ± 0.8, Cu 10.65 ± 0.05, As 0.05 ± 0.002, Pb 0.2 ± 0.01, and Cr 0.5 ± 0.03 in mg/kg. All measured concentrations were below WHO standards. The estimated daily intake of metals from both food was found to be below the Maximum Recommended Daily Intake (MRDI). The hazard index for peanuts was within safe limits, indicating no significant non-carcinogenic health risks. In contrast, the hazard index for date palms exceeded 1, suggesting potential non-carcinogenic health risks. Incremental lifetime cancer risks were within allowable limits. In conclusion, the concentrations of heavy metals in peanuts and date palms from the Jigjiga market are within safe limits set by the WHO. [ABSTRACT FROM AUTHOR]

Serverless computing is one of the recent compelling paradigms in cloud computing. Serverless computing can quickly run user applications and services regardless of the underlying server architecture. Despite the availability of several commercial and open-source serverless platforms, there are still some open issues and challenges to address. One of the key concerns in serverless computing platforms is security. Therefore, in this paper, we present a multi-layer abstract model of serverless computing for an security investigation. We conduct a quantitative analysis of security risks for each layer. We observe that the Attack Tree and Attack-Defense Tree methodologies are viable approaches in this regard. Consequently, we make use of the Attack Tree and the Attack-Defense Tree to quantify the security risks and countermeasures of serverless computing. We also propose a novel measure called the Relative Risk Matrix (RRM) to quantify the probability of attack success. Stakeholders including application developers, researchers, and cloud providers can potentially apply these findings and implications to better understand and further enhance the security of serverless computing. [ABSTRACT FROM AUTHOR]

Multimedia streaming has become integral to modern living, reshaping entertainment consumption, information access, and global engagement. The ascent of cloud computing, particularly serverless architectures, plays a pivotal role in this transformation, offering dynamic resource allocation, parallel execution, and automatic scaling-especially beneficial in HTTP Adaptive Streaming (HAS) applications. This study presents an event-driven serverless cloud edge platform with graphics processing units (GPUs), managed by Knative, tailored for video encoding. Two implementations of the High Efficiency Video Coding (HEVC) codec have been encapsulated in the functions: HEVC NVENC (Nvidia Encoder), that uses GPU acceleration, and x265 that only uses CPUs. Experiments focused on measuring the impact of replica requested resources on cold start, scalability and resource consumption with different allocated resources on slim and fat virtual machines (VMs). The best results are obtained when four slim replicas of the functions are deployed on a fat VM with a 8.4% reduction in encoding time for x265 and a 15.2% improvement for HEVC NVENC compared with other deployment scenarios. Comparatively, HEVC NVENC encoding is 8.3 times faster than x265. In multiresolution scenarios, GPU encoding drastically reduces segment encoding time by a factor of 12.4 between non-GPU and GPU-accelerated. These findings are important for live streaming applications where low latency is critical at all stages of the streaming process. [ABSTRACT FROM AUTHOR]

In this work, flower-like zinc oxide (ZnO) nanostructures were synthesized using hydrothermal synthesis. The fabricated nanoflowers were used as adsorbents for the removal of heavy metal ions such as lead and chrome. Morphological assessments and chemical investigations of the ZnO nanoflowers were conducted by using X-ray diffraction, field emission electron microscopy, energy dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy techniques. To optimize the heavy metal recovery process optimum parameters like pH, eluent type, adsorbent amount, solution volume, and adsorption time were studied; flame atomic absorption spectrometry was used in the optimization process. The optimum conditions for Cr(VI) and Pb(II) were determined as 3 M HNO3, pH 6.5, 20 mL, 30 min. But the amount of ZnO nanoflowers for Cr(VI) and Pb(II) was determined as 200 and 50 mg, respectively. Outstanding heavy metal ion removal performance of the ZnO nanoflowers was achieved on spinach (NIST-SRM1570a), and apple leaf (NIST-SRM 1515) for the method validation where the solid phase extraction technique was used as the main enrichment method. The flame AAS method was applied to determine for Cr(VI) and Pb(II) metal ions in real samples (spinach, rocket leaf, collard leaf, parsley, bottled drinking water and hardaliye), after and before enrichment on the present ZnO. Relative standard deviation (%RSD) was found in the range of 0.2–5.3. [ABSTRACT FROM AUTHOR]

Heavy metal ions threaten public health and marine life; thus, removal of heavy metals is essential for the environment. Bi2S3 nanostructures are active materials which used in various applications. In this work, we produced Bi2S3 nanoflowers using hydrothermal synthesis and assessed their Cd2+ ions removal capability. Structural properties of the Bi2S3 nanoflowers were assessed by various like scanning electron microscopy, X-ray diffraction. Chemical characteristics of the materials were confirmed using energy dispersive X-ray spectra. Different parameters affecting the Cd2+ ion recovery was worked some of which are adsorbent amount, Cd2+ ion concentration, pH, adsorbent time, eluent type and amount, etc. For cadmium, the optimum pH was determined 8.0 for 1 M HNO3 eluent. Optimum adsorbent amount was determined as 150 mg while optimum recovery duration was found as 30 min. Bi2S3 nanoparticles managed to achieve 99.3% Cd2+ recovery rate in 5 mL eluent volume, for optimum condition. The adsorption capacity of the Bi2S3 nanoflowers was found to be promising and therefore, it was illustrated that Bi2S3 nanoflowers are good candidates as sorbent for water remediation applications. [ABSTRACT FROM AUTHOR]

The concentrations of potentially toxic metals like lead (Pb), cadmium (Cd), and mercury (Hg) in healthy lactating mothers of Lahore city were estimated during 2020–2021 with the help of a flame atomic absorption spectrometer (FAAS). Seventy samples of breast milk were collected from two different age groups, namely, G-1 (25–30 years) and G-2 (31–40 years). The results showed that Cd contents were below the detection limit of the measuring instrument; however, the Pb and Hg contents were detected with great ease. The mean concentrations of Pb and Hg in the G-1 corresponding to the age between 25 and 30 years were observed to be 1.914 ± 0.493 μg/L and 10.432 ± 3.249 μg/L, respectively. For the G-2 with an age limit between 31 and 40 years, the concentrations of Pb and Hg were estimated to be 2.045 ± 0.502 μg/L and 11.527 ± 3.231 μg/L, respectively. The T-test analysis of concentrations of these toxic metals indicated a significant correlation between the content levels of Pb and Hg (p < 0.05). The observed values of toxic metals were significantly more frequent than those suggested by WHO (World Health Organization). An increase in the concentrations of Pb and Hg is directly associated with the location of the target population. As a result, it is turned out that the majority of the lactating woman with significantly high levels of Pb and Hg belongs to industrial areas of Lahore. To avoid such conditions, residential areas must be at larger distances, in addition, to strictly abiding by the environmental policies of the government. [ABSTRACT FROM AUTHOR]

Laryngeal cancer, a rare form of head and neck cancer, is more common in men, and various factors play important roles in its etiology. In the current study, trace elemental contents in the scalp hair of laryngeal cancer patients and healthy subjects were evaluated. Selected essential and toxic elements were measured using flame atomic absorption spectrophotometry after the hair samples were digested with HNO3–HClO4. The mean/median levels of Pb in the scalp hair of patients were significantly higher than the healthy donors, but Sr, Zn, and Co exhibited comparatively lower levels in the laryngeal cancer patients. In comparison to healthy donors, the correlation pattern among the elements in the hair of the patients exhibited diverse mutual relationships. The multivariate apportionment of the elemental levels in the scalp hair of both donor groups was significantly divergent. The average elemental levels varied significantly among the cancer types (glottic, supraglottic, transglottic, and subglottic) as well as the cancer stages (I, II, III, IV). The average levels of the elements also exhibited considerable variations depending on the donors' habitat, gender, food, and smoking habits. Overall, the study revealed significantly divergent disparities among the elemental contents in the scalp hair of the laryngeal cancer patients in comparison with counterpart controls. [ABSTRACT FROM AUTHOR]

In order to eliminate the effects of seawater matrix on the precise/accurate determination of elements, new and efficient analytical procedure requires. In this study, co-precipitation method based on the triethylamine (TEA)-assisted Mg(OH)2 was performed to eliminate side-effects of seawater medium on the determination with flame atomic absorption spectrometry (FAAS) prior to the preconcentration of nickel by an optimized dispersive liquid–liquid microextraction (DLLME) method. Under the optimum conditions of the presented method, the limit of detection and quantification (LOD, LOQ) values obtained for nickel were found as 16.1 and 53.8 μg kg−1, respectively. Seawater samples collected from West Antarctic region were used for real sample applications to check the accuracy and applicability of developed method, and satisfying recovery results (86–97%) were obtained. In addition to this, the digital image-based colorimetric detection system and the UV-Vis system were applied to confirm the applicability of the developed DLLME-FAAS method in other analytical systems. [ABSTRACT FROM AUTHOR]

Function-as-a-Service (FaaS) is a popular programming model for building serverless applications, supported by all major cloud providers and many open-source software frameworks. One of the main challenges for FaaS providers is providing fault tolerance for the deployed applications, that is, providing the ability to mask failures of function invocations from clients. The basic fault tolerance approach in current FaaS platforms is automatically retrying function invocations. Although the retry approach is well suited for transient failures, it incurs delays in recovering from other types of failures, such as node crashes. This paper proposes the integration of a Request Replication mechanism in FaaS platforms and describes how this integration was implemented in Fission, a well-known, open-source platform. It provides a detailed experimental comparison of the proposed approach with the retry approach and an Active-Standby approach in terms of performance, availability, and resource consumption under different failure scenarios. [ABSTRACT FROM AUTHOR]

The natural radioactivity of 238U, 232Th, and 40K was measured in selected samples from 11 monitoring stations along the Euphrates River in Elanbar governorate in 2022, using a NaI (Tl) gamma-ray spectroscopy detector 3" in diameter. The results showed that the average activity concentrations of 238U (214Bi), 232Th (208Tl), and 40K in the water samples were 4.29, 1.62, and 10.95 Bq/L, respectively. Cations and heavy metals were measured using flame and flame atomic absorption spectroscopy (FAAS). The concentrations of Pb2+, Na+, and K+ were 0.02, 207, and 22 mg/L, respectively. According to the information provided by the World Health Organization, the samples studied in this work revealed the correlation between the heavy metals and cations. On the whole, waters of Elanbar governorate are unsafe in terms of the concentration of natural radioactive and heavy metals. [ABSTRACT FROM AUTHOR]

Function-as-a-Service (FaaS) is an event-based reactive programming model where functions run in ephemeral stateless containers for short duration. For building complex serverless applications, function composition is crucial to coordinate and synchronize the workflow of an application. Some serverless orchestration systems exist, but they are in their primitive state and do not provide inherent support for non-trivial workflows like, Fork-Join. To address this gap, we propose a fully serverless and scalable design model ReactiveFnJ for Fork-Join workflow. The intent of this work is to illustrate a design which is completely choreographed, reactive, asynchronous, and represents a dynamic composition model for serverless applications based on Fork-Join workflow. Our design uses two innovative patterns, namely, Relay Composition and Master-Worker Composition to solve execution time-out challenges. As a Proof-of-Concept (PoC), the prototypical implementation of Split-Sort-Merge use case, based on Fork-Join workflow is discussed and evaluated. The ReactiveFnJ handles embarrassingly parallel computations, and its design does not depend on any external orchestration services, messaging services, and queue services. ReactiveFnJ facilitates in designing fully automated pipelines for distributed data processing systems, satisfying the Serverless Trilemma in true essence. A file of any size can be processed using our effective and extensible design without facing execution time-out challenges. The proposed model is generic and can be applied to a wide range of serverless applications that are based on the Fork-Join workflow pattern. It fosters the choreographed serverless composition for complex workflows. The proposed design model is useful for software engineers and developers in industry and commercial organizations, total solution vendors and academic researchers. [ABSTRACT FROM AUTHOR]

Serverless computing is stepping forward to provide a cloud environment that mainly focuses on managing infrastructure, resources and configurations on the behalf of a user. Research in this field can't rely on commercial providers such as AWS and Azure, as their inflexibility and cost often limits the required levels of reproducibility and scalability. Therefore, simulators have been opted as an alternative solution by the research community. They offer a reduced-cost and easy-setup environment. To get respectable precision, simulators use real traces collected and offered by commercial providers. These traces represent comprehensive information of executed tasks that reflect user behaviour. Due to serverless computing's recency, typical workload traces employed by IaaS simulators are not well adoptable to the new computing model. In this paper, we propose an approach for generating realistic serverless traces. We enhance our previous generator approach that was based on the Azure Functions dataset. Our new, genetic algorithm based approach improves the statistical properties of the generated traces. We also enabled arbitrary scaling of the workload, while maintaining real users' behaviour. These advances further support reproducibility in the serverless research community. We validated the results of our generator approach using the coefficient of determination ( R 2 ), which shows that our generated workload closely matches the original dataset's characteristics in terms of execution time, memory utilisation as well as user participation percentage. To demonstrate the benefits of the reusability of the generated traces, we applied them with a diverse set of simulators and shown that they offer reproducible results independently of the simulator used. [ABSTRACT FROM AUTHOR]

This study presents a simple, sensitive, and accurate method for the determination of nickel by flame atomic absorption spectrometry (FAAS). Prior to instrumental measurement, a deep eutectic solvent-based simultaneous complexation and preconcentration (DES-SCP) method was used to preconcentrate nickel from aqueous solution into measurable quantities. The efficiency of the extraction method was enhanced by forming a non-ionic complex of nickel using dithizone as ligand. By mixing the ligand with the DES extractant, simultaneous complexation and preconcentration of nickel were achieved in a single step. Under optimum conditions of the extraction method, the limit of detection (LOD) and the limit of quantification (LOQ) values were found to be 2.4 and 8.0 ng/mL, respectively. With respect to direct FAAS measurement, the developed method enhanced the sensitivity of nickel determination by about 169 folds. The accuracy and applicability of the developed method were evaluated by performing spike recovery experiments with lake water sampled from Antarctica. Satisfactory recovery results in the range of 94.0–113.7% were recorded and this validated the developed method as an efficient and green alternative for nickel determination. [ABSTRACT FROM AUTHOR]

In this study, a green, simple and effective preconcentration method named as spray-assisted fine droplet formation-liquid phase microextraction (SAFDF-LPME) before the flame atomic absorption spectrophotometry (FAAS) measurement for cobalt determination was developed. The method reduces the external dispersive solvent usage by using a simple spraying apparatus to obtain fine droplets of the extraction solvent. SAFDF-LPME method also consists of simultaneous complexation and extraction which indicates the environmental benevolence of the developed method. This method minimized the relative errors with high repeatability and accuracy by reducing the experimental steps. The influential parameters such as buffer type, buffer solution volume, extraction solvent/ligand solution volume (spraying cycle), and mixing period were systematically optimized by the univariate optimization procedure. With the optimum parameters applied, the detection power of the FAAS system was enhanced to about 110-folds with respect to 2.2 ng mL−1 detection limit calculated for the proposed method. Bottled drinking water samples from Fiji Islands were used to demonstrate the applicability of the developed method for the accurate determination of trace cobalt in real sample matrices. Percent recovery results obtained between 95.5 and 88.5% showed the suitability of the developed method in the determination of cobalt at trace levels even in complex sample matrices. [ABSTRACT FROM AUTHOR]

Laryngeal carcinoma is one of the common types of head and neck cancer, with men being more likely than women to develop it. Diet, age, gender, smoking habits, and environmental factors play important roles in its development. The goal of this study was to ascertain if there were imbalances in essential and toxic trace metals owing to the initiation and progression of laryngeal cancer. Atomic absorption spectrometry was employed to quantify selected macroelements, and essential/toxic trace metals in blood of the cancerous patients and matching controls. Significantly higher concentrations of Pb, Cu, Fe, and Sr while substantially lower levels of Na, K, Ca, and Mg were observed in the cancer patients compared with the controls. Considerably disparate mutual relationships among the macroelements, and essential/toxic trace metals in the patients and controls were manifested by their correlation coefficients. Similarly, multivariate apportionment of the metal levels showed appreciably diverse associations and grouping in the patients and controls. The laryngeal cancer patients exhibited significant disparities in the metal levels among various sub-types (supraglottic, subglottic, transglottic, and glottic cancer) and stages (I, II, III, and IV) of the disease. Most of the metals revealed distinct differences based on the gender, habitat, age, eating preferences, and smoking habits in both donor groups. Overall, the study demonstrated significant imbalances among the macroelements, and essential/toxic trace metal levels in the blood of laryngeal cancer patients compared to the controls. [ABSTRACT FROM AUTHOR]

Honey is a natural, sugary and sticky liquid that is produced from the nectars of flowers by the bees. This study aimed to analyze the concentration of some selected heavy Metals in honey samples. 1 g of honey sample was digested by a hot plate using 9ml of HNO3 and 3ml of H2O2. The concentrations of the heavy metals in the digested were detected using a flame atomic absorption spectrometer. The results of this study found that the concentrations of the heavy metals in the honey samples were ranged from 1.97 to 2.04 µg/g for Zn, 1.93 µg/g to 2 µg/g for Cu, 0.83 to 1.01 µg/g for Mn, 0.25 to 0.45 µg/g for Cr, 0.025–0.031 µg/g for Cd. However, Pb was not detected in all honey samples. Hence, the levels of heavy metals found were below the permitted levels set by the World Health Organization. From the results, the levels of heavy metals found were below the permitted levels set by the World Health Organization. Thus, the heavy metals in the sampled honey are safe for human consumption in these selected areas. [ABSTRACT FROM AUTHOR]

Even though there are reported methods for the quantification of free amino acids (FAAs) in biological products, no work has been done on the analysis of these substances in formulations. Moreover, further research is required as the reported methods do not fulfill analytical method requirements. The objective of this study was, therefore, to develop and validate a rapid, reliable, and appropriate RP-HPLC/DAD method for the simultaneous determination of 18 FAAs (l-Ala, l-Arg, l-Asn, l-Asp, l-Gln, l-Glu, l-Gly, l-His, l-Ile, l-Lue, l-Lys, l-Met, l-Orn, l-Phe, l-Pro, l-Ser, l-Thr, and l-Val) in topical formulations. After appropriate method development, the technique was validated for selectivity, linearity and range, limit of detection, limit of quantification, precision, and accuracy. The samples were derivatized with 9-fluorenylmethyl chloroformate (Fmoc-Cl). Chromatographic separation was performed on InfinityLab Poroshell 120 E.C 18 (3 × 50) mm, 2.7 μm column at 25 °C. The mobile phase consisting of water and acetonitrile adjusted to appropriate pH was pumped in gradient mode at a flow rate of 0.7 mL/min. Ten microliters were injected and analyte detection was conducted using a DAD. The results indicate that the method was selective for these FAAs. It was linear over the concentration range of 5–80 µM with a correlation coefficient greater than 0.995. Moreover, it was sensitive, precise, accurate, and robust. All the reported drawbacks of RP-HPLC-based analysis of FAAs were resolved, and hence, this new method can be considered appropriate for the analysis of these FAAs in topical formulations. [ABSTRACT FROM AUTHOR]

Today's industry has gradually realized the importance of lifting efficiency and saving costs during the life-cycle of an application. In particular, we see that most of the cloud-based applications and services often consist of hundreds of micro-services; however, the traditional monolithic pattern is no longer suitable for today's development life-cycle. This is due to the difficulties of maintenance, scale, load balance, and many other factors associated with it. Consequently, people switch their focus on containerization—a lightweight virtualization technology. The saving grace is that it can use machine resources more efficiently than the virtual machine (VM). In VM, a guest OS is required to simulate on the host machine, whereas containerization enables applications to share a common OS. Furthermore, containerization facilitates users to create, delete, or deploy containers effortlessly. In order to manipulate and manage the multiple containers, the leading Cloud providers introduced the container orchestration platforms, such as Kubernetes, Docker Swarm, Nomad, and many others. In this paper, a rigorous study on Kubernetes from an administrator's perspective is conducted. In a later stage, serverless computing paradigm was redefined and integrated with Kubernetes to accelerate the development of software applications. Theoretical knowledge and experimental evaluation show that this novel approach can be accommodated by the developers to design software architecture and development more efficiently and effectively by minimizing the cost charged by public cloud providers (such as AWS, GCP, Azure). However, serverless functions are attached with several issues, such as security threats, cold start problem, inadequacy of function debugging, and many other. Consequently, the challenge is to find ways to address these issues. However, there are difficulties and hardships in addressing all the issues altogether. Respectively, in this paper, we simply narrow down our analysis toward the security aspects of serverless. In particular, we quantitatively measure the success probability of attack in serverless (using Attack Tree and Attack–Defense Tree) with the possible attack scenarios and the related countermeasures. Thereafter, we show how the quantification can reflect toward the end-to-end security enhancement. In fine, this study concludes with research challenges such as the burdensome and error-prone steps of setting the platform, and investigating the existing security vulnerabilities of serverless computing, and possible future directions. [ABSTRACT FROM AUTHOR]

CuCo2O4 nanoparticle has been synthesized, characterized and firstly used as solid-phase extractant for the dispersive solid-phase extraction of Pb(II) in the presented work. The important parameters like pH of the working media, type of eluent solution and its volume, adsorbent amount, adsorption–desorption contact times, sample volume have been optimized. Lead (II) ions were quantitatively recovered on CuCo2O4 nanoparticle at pH 6.0 with 10 mg of adsorbent and eluted by using 2 mL of 1 M HCl. The influences of some cations and anions on the recoveries were also investigated. While the preconcentration factor was 25, the limit of detection was calculated as 6.5 µg/L. The method was checked by applying the method to certified reference material (TMDA-53.3). The method was successfully applied to various food, cigarette and water samples. [ABSTRACT FROM AUTHOR]

This paper presents a Function-as-a-Service (FaaS) approach for deploying managed cloud functions onto heterogeneous cloud infrastructures. Current FaaS systems, such as AWS Lambda, allow domain-specific functionality, such as AI, HPC and image processing, to be deployed in the cloud while abstracting users from infrastructure and platform concerns. Existing approaches, however, use a single type of resource configuration to execute all function requests. In this paper, we present a novel FaaS approach that allows cloud functions to be effectively executed across heterogeneous compute resources, including hardware accelerators such as GPUs and FPGAs. We implement heterogeneous scheduling to tailor resource selection to each request, taking into account performance and cost concerns. In this way, our approach makes use of different processor types and quantities (e.g. 2 CPU cores), uniquely suited to handle different types of workload, potentially providing improved performance at a reduced cost. We validate our approach in three application domains: machine learning, bio-informatics, and physics, and target a hardware platform with a combined computational capacity of 24 FPGAs and 12 CPU cores. Compared to traditional FaaS, our approach achieves a cost improvement for non-uniform traffic of up to 8.9 times, while maintaining performance objectives. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a potentially toxic element with significant environmental interest. Simple and sensitive analytical methods are necessary to allow determination of this element at trace levels using sample preparation procedures related to green chemistry. For this, calcium alginate beads (CA-beads), a low-cost and environmentally friendly biopolymer, have been proposed for extraction and preconcentration of Pb2+ in river water samples and determination by flame atomic absorption spectrometry (FAAS). CA-beads were prepared and applied to extract and preconcentrate Pb2+ in river water samples, providing an enrichment factor (EF) of 50, enhancement factor (E) of 54, a detection limit of 2 μg L−1, and a relative standard deviation < 5%. The extraction of Pb2+ in CA-beads achieved good selectivity, with recoveries from 94.8 to 100.2% in real samples, demonstrating the good accuracy of the proposed method. The results were also compared to those obtained by ICP-MS. The reuse of CA-beads was evaluated for six cycles, and under these conditions, the extraction and preconcentration efficiency of Pb2+ were not significantly affected. The developed methodology was applied to determine Pb2+ in water samples from rivers that are part of the hydrographic areas of Tibagi and Pitangui Rivers, in which the Pb2+ concentration was less than 2 μg L−1, a concentration lower than that established by Brazilian legislation for class I and II rivers. [ABSTRACT FROM AUTHOR]

A green supramolecular solvent-based liquid-phase microextraction (SUPRAs-LPME) strategy was developed and used for the preconcentration of iron in clove tea and tap water samples at trace levels. Complex formation occurred between the iron and a Schiff base ligand obtained from 5-bromosalicylaldehyde and o-phenylenediamine reaction, and the coordinate complex formed was extracted to supramolecular solvent phase. Limit of detection and quantification values was found as 4.3 and 14.2 μgL−1, respectively, under the optimized conditions. When the analytical performance values obtained with SQT-FAAS, SUPRAs-LPME-FAAS and SUPRAs-LPME-SQT-FAAS are compared with FAAS, enhancements in detection power based on the LOD comparisons were calculated as 1.8, 31.4 and 65.8 times, respectively. The presented method was successfully applied to the determination of water-soluble iron in real clove tea in addition to tap water samples at trace levels, and the percent recoveries were obtained as 94.7–103.0% and 96.9–107.6%, respectively. [ABSTRACT FROM AUTHOR]

A simple, rapid and efficient method of preconcentration and determination of selected toxic heavy metals from herbal phytopharmaceutical product matrices using inductively coupled plasma and flame atomic absorption spectrometry after preconcentration with chelating resin (chelex-100) was developed. In this study, 24 samples representing phytopharmaceutical remedies in different dosage forms such as tablet, capsule, suppository, syrup and tea bag that are available in Pharmaceutical Jordanian companies were investigated for the presence of Pb, Cd, Al and As to establish their normal concentrations range and consider their levels according to some worldwide permissible limit guidelines. The %relative standard deviation was < 5%. Pb, Cd, and Al concentrations were ranged (0.01–30.84 μg/g), (0.001–0.85 µgg−1) and (1.81–215.19 µgg−1), respectively, whereas As level was below the detection limit. The percent contribution of raw material heavy metal content for tablet dosage forms was in the average of 88.39%, 79.85% and 83.13% for Pb, Cd and Al, respectively. [ABSTRACT FROM AUTHOR]

An efficient, sensitive, and easy deep eutectic solvent based (DESb) liquid phase microextraction (LPME) method was developed to preconcentrate palladium for quantification at trace level by a flame atomic absorption spectrometry (FAAS) system, equipped with a lab made slotted quartz tube (SQT). All parameters of the DESb-LPME-SQT-FAAS system were optimized to lower the detection limit of the system. Using the optimized conditions, quantification and detection limits were obtained as 24.7 and 7.4 μg L−1, respectively, which are compatible with the literature findings. Detection power of the FAAS system was enhanced by almost 50-fold using the optimum method based on LOD comparison. Recovery experiments were also performed with spiked wastewater matrix to examine the applicability/validity of the proposed method. The % recovery results were calculated between 85 and 91%. This established that the applicability of the developed method is high, and determination of this element in complex matrix can be performed accurately using the developed method. [ABSTRACT FROM AUTHOR]

Function-as-a-Service (FaaS) allows developers to define, orchestrate and run modular event-based pieces of code on virtualised resources, without the burden of managing the underlying infrastructure nor the life-cycle of such pieces of code. Indeed, FaaS providers offer resource auto-provisioning, auto-scaling and pay-per-use billing at no costs for idle time. This makes it easy to scale running code and it represents an effective and increasingly adopted way to deliver software. This article aims at offering an overview of the existing literature in the field of next-gen FaaS from three different perspectives: (i) the definition of FaaS orchestrations, (ii) the execution of FaaS orchestrations in Fog computing environments, and (iii) the security of FaaS orchestrations. Our analysis identify trends and gaps in the literature, paving the way to further research on securing FaaS orchestrations in Fog computing landscapes. [ABSTRACT FROM AUTHOR]

In the present study, Fe, Cu, Cr, Cd, Pb, Ni, and Al concentrations in Caiman latirostris and Testudines blood from the Tapacurá reservoir, Pernambuco, Brazil, were investigated. Blood was acid digested with HNO3, and metals were determined by ICP-OES and FAAS. Lead showed concentrations below the established limit of detection. Eighty animals were evaluated, forty from each group. The levels of all elements were statistically significant when compared between the two studied taxa (p < 0.05). In caimans, significant differences between young and adults were observed for chromium (p = 0.0539) and aluminum (p = 0.0515). Testudines showed no statistically significant differences for the variable age structure. Gender did not influence metal concentrations detected in the present study for either group. Differences between species of testudines were significant for Fe between Mesoclemmys tuberculata vs Phrynops geoffroanus (p = 0.0932) and Kinosternon scorpioides vs Phrynops geoffroanus (p = 0.063). The inter-elementary correlations showed statistically significant differences between the elements Cr vs Al (R2 = 0.52), Cr vs Cd (0.43), Cd vs Cu (R2 = 0.41), Ni vs Cu (R2 = 0.31), Ni vs Cr (R2 = 0.30), Al vs Cd (R2 = 0.27), and Cd vs Fe (R2 = 0.26). It is concluded that blood is an excellent predictor of metals in crocodilians and testudines in the Tapacurá reservoir, with statistically significant differences when correlated to concentrations such as size and species studied. In addition, it evidenced data that prove the exposure of these animals to metals, with strong inter-elementary correlations and opening doors for future studies that seek to understand possible biological effects caused in the studied taxa. [ABSTRACT FROM AUTHOR]

Thyroid cancer is among the most common type of head and neck cancer; diet, age, gender and environmental factors play vital roles in its malignancy. The present study was carried out to assess the imbalances in the contents of trace metals due to onset and progression of thyroid cancer. Scalp hair was used as matrix for the evaluation of toxic and trace metals. Quantification of the metals was done through atomic absorption spectrometry. In comparison with healthy subjects, the thyroid cancer patients revealed significantly higher median levels of Mn (71%), Co (64%), Cr (55%), K (49%), Fe (45%), Mg (42%), Pb (36%), Na (30%), and Ni (26%), while the median level of Zn was considerably lower in the patients. The correlation coefficients among the metals in the patients demonstrated significantly different communal relationships compared with the healthy counterparts. Multivariate methods exhibited noticeably dissimilar apportionment among the metals in the patients than the controls. Significant disparities in the metal levels were also noticed for various types (anaplastic thyroid cancer, follicular thyroid cancer, papillary thyroid cancer, and medullary thyroid cancer) as well as stages (I, II, III, and IV) among the thyroid cancer patients. Majority of the metals revealed perceptible disparities in their contents based on gender, habitat, dietary habits, and smoking habits of the patients and controls. Overall, the study showed significantly divergent distribution and associations of the essential and toxic metal levels in the scalp hair of the patients in comparison with the levels in controls. [ABSTRACT FROM AUTHOR]

A current study has been carried out to assess the level of selected heavy metals like Cr, Cd, Zn, Mn, Fe, Co, Pb, and Ni in six branded noodles, i.e., Maggi, Knorr, Shan shoop, Shinramayun, Indomie, and Mama. The concentration of Cr, Cd, Zn, Mn, Fe, and Co was observed in the range of 3.3–9.7, 0.066–0.59, 6.2–11.4, 2.4–6.3, 4.8–17.5, and 0.39–0.74 mg kg−1 respectively while that of Pb and Ni was below the detection limit. High Cd (0.59 mg kg−1), Fe (17.5 mg kg−1), and Co (0.74 mg kg−1) were found in Maggi; high Cr (9.7 mg kg−1) and Mn (6.3 mg kg−1) were found in Mama while high Zn (11.4 mg kg−1) was found in Knorr. The health risk associated with the use of noodles in Pakistan was evaluated by using estimated dietary intake (EDI), target hazard quotients (THQs), and hazard index (HI). THQ values found for Zn, Mn, Fe, and Co were found below 1 while those for Cd in four samples were below 1 and for Maggi, they were higher than 1. THQ values for Cr in all samples were above 1. Cr and Cd concentrations were a little bit higher than those of the WHO/FAO permissible limits; Zn and Fe concentrations were found within the limit while for Mn and Co WHO/FAO limits are not yet established. The THQ values for Cr and its concentration in all samples show that it could have a detrimental effect on the users of noodles in Pakistan. [ABSTRACT FROM AUTHOR]

Serverless computing and a function execution model, Function-as-a-Service (FaaS), are currently receiving considerable attention from both academia and industry. One of the reasons for the success of serverless computing is its straightforward interface that abstracts complex internals of cloud computing resource usage and configurations. However, this approach may result in hiding too much information about how underlying cloud resources would work, entailing that users cannot predict how their applications will perform, especially for IO-heavy ones. To address this issue, we evaluate several aspects of network and disk IO performance with realistic workloads using public FaaS systems. Our analysis reveals that current public FaaS systems do not provide appropriate levels of IO performance differentiation, and the ability to isolate network resource allocation during concurrent execution is rarely offered by service providers. Based on the results presented in this paper, we insist that it must be mandatory for network and disk IO resource performance of FaaS to be more visible and predictable, as is the case for memory and CPU, in order to expand serverless computing applications to data-intensive ones. [ABSTRACT FROM AUTHOR]

In this study, switchable solvent (SS) for liquid-phase microextraction (LPME) was used as a tool to preconcentrate nickel from aqueous samples for determination by flame atomic absorption spectrometry. The SS-LPME method was optimized thoroughly to boost the absorbance signal of nickel for trace level determination. Parameters optimized included switchable solvent volume, sodium hydroxide concentration, sodium hydroxide volume, and eluent volume. The SS-LPME method enhanced the detection power by about 32-folds, and a slotted quartz tube (SQT) was used to obtain 2.6-folds increase in detection power. The combination of LPME and SQT-FAAS produced 104-folds enhancement, correlating to a limit of detection value of 1.8 μg/L. Low relative standard deviations calculated for the lowest calibration concentration indicated good repeatability for replicate measurements. Accuracy of the optimized method and its applicability to real samples was tested on two river samples. The results (85–103%) obtained from the spike recovery experiments were satisfactory. [ABSTRACT FROM AUTHOR]

Metal complexes for medical applications are the promising area of research and metallo-drugs have been developed and evaluated to enhance the efficiency of drugs and minimize their side effects. This study describes the synthesis of a Schiff base ligand (Z)-3-bromo-5-((p-tolylimino)methyl)phenol from the reaction of 5-bromosalicilaldehyde and p-toluidine, and its subsequent complexation with nickel. Characterization and cell viability studies were performed for both Schiff base ligand and its metal complex with 1H-NMR, FTIR, TG analysis, and UV–VIS spectrometry. With the aim of proving the Ni complex formation, quantitative analysis was done with flame atomic absorption spectrometry. The recovery result obtained for the formed complex was 103.9%. The cell viability of human thyroid gland undifferentiated carcinoma cells (8305C) treated with the Ni-ligand complex was determined as 12.7 ± 0.17%. It was observed that the nickel complex could be a significant anticancer agent as tested by the MTT assay method. [ABSTRACT FROM AUTHOR]

Twenty-four-hour (h) urinary copper content is considered as the most suitable tool for the diagnosis of Wilson's disease (WD); however, it is less accurate, time-consuming, and non-economical. Consequently, in the present study, an alternative method through measuring the morning (first) urine copper (Cu) concentration is proposed for the diagnosis of WD, which is more accurate, precise, faster, and cheaper. For this purpose, a sensitive, accurate, and precise analytical method was developed and validated in regard to Commission Decision 657/2002/EC, Council Directive 333/2007/EC, ISO/IEC 17025:2005, and EURACHEM 1998 for the determination of Cu in urine using flame atomic absorption spectrometry (FAAS). The methods LoD and LoQ for urine Cu were estimated as 6.68 μg/L and 16.7 μg/L respectively. The accuracy of the method was found to be 93.70–101.88% calculated from the spike recovery experiment. The RSDs for the repeatability and reproducibility precision were measured as 0.67–3.16 and 0.26–1.95 respectively. The method validation performance criteria indicated that the method was suitable for the determination of Cu in urine. The validated method was then applied for the determination of Cu in both 24 h and first urine. From the analysis, it was found that the amount of Cu per liter in the first urine was almost equivalent to the amount of Cu per 24 h indicating that instead of considering the 24-h urine, morning (first) urine investigation might be an alternative approach for the diagnosis of WD. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) air pollution in Bosnia and Herzegovina by using a lichen, Hypogymnia physodes. Metal content was determined by flame atomic absorption spectrometry (FAAS) and was between very high naturality or alteration to middle naturality or alteration. Strong correlations between Cr and Ni confirmed mainly anthropogenic sources. The scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS) analysis of C, O, Na, Mg, Al, Si, P, S, Cl, K, Ca, V, Co, As, Sn, Sb, Hg and Bi were performed on the lichen surface and hyphae of the transplanted samples. Despite significant damage to tissue and cell integrity, the recurrent presence of particulate matter in lichen indicates the considerable presence of dust in the urban atmosphere which, according to chemical composition, may be due to anthropogenic and natural sources such as soil. [ABSTRACT FROM AUTHOR]

A novel and green ultrasonic-assisted liquid phase microextraction method (LPME) based on deep eutectic solvents (DESs) has been developed for the pre-concentration and extraction of lead from cigarette tobacco and food samples prior to flame atomic absorption spectrometer (FAAS) determination. Multivariate Plackett-Burman design has been employed which make the proposed method more easy and fast as compare to routine practices and eliminated the step by step optimization process. Further, accuracy of the developed UA-DES-LPME has been checked with analysis of certified reference material and addition-recovery experiments for tobacco and food samples. The developed method showed a 4.4 µg L− 1 of limit of detection (LOD) and 14.6 µg L− 1 of limit of quantification (LOQ) with the 4.0% of relative standard deviation (RSD). Moreover, the developed method is more user-friendly, faster, and easier as compared to reported methods. [ABSTRACT FROM AUTHOR]

Antimony is known to have some adverse health effects on human health. Flame atomic absorption spectrometry (FAAS) is a widely used instrumental for the determination of antimony and other metals. However, it lacks the sensitivity to determine these metals at trace levels. This study was aimed at overcoming this setback by using hydrogen assisted T-shaped slotted quartz tube technique to preconcentrate and determine antimony by FAAS. All the system parameters were optimized to enhance the detection power of the system. Under the optimum experimental conditions, the limits of detection and quantification were found to be 0.75 and 2.49 µg L−1, respectively with R2 value of 0.9999. Accuracy of the developed method was validated by experimental results agreeing to the certified value of a standard reference material. Recovery studies were also carried out to determine the method's applicability to tap and mineral water samples, and the results obtained were appreciable. [ABSTRACT FROM AUTHOR]

In this study, ultrasound-assisted cloud point extraction (UA-CPE) method was developed for the determination of Ni(II) and Co(II) in milk-based products. After extraction and preconcentration, the Ni(II) and Co(II) contents of samples were determined by flame atomic absorption spectrometry (FAAS). After their complexation with hydroxy naphthol blue (HNB) in the presence of cationic surfactant, CTAB at pH 4.0, the Ni(II) and Co(II) were taken within the micellar phase of nonionic surfactant, TX-114. The micellar phase containing the analytes were diluted to a volume of 0.7 mL with 1.0-mol/L HNO3 in ethanol to reduce its viscosity and to facilitate sample treatment and then was analyzed by FAAS. The various analytical parameters affecting UA-CPE efficiency were investigated. The analytical features obtained after optimization are as follows: limits of detection are 0.56 and 0.78 μg/L; sensitivity enhancement factors are 48.6 and 53.9; the calibration curves were linear 3-180 and 2-160 μg/L for Co(II) and Ni(II), respectively, after preconcentration of 50-fold. The precision (as RSD%) between 1.8-3.6% and 2.2-3.8% (25 and 100 μg/L, n = 5) for Ni(II) and Co(II), respectively. The accuracy was statistically verified by analysis of two certified reference material samples (CRMs), including recovery studies after spiking. The method was applied to the analysis of milk-based samples with satisfied results. [ABSTRACT FROM AUTHOR]

In this study, dispersive liquid-liquid microextraction was systematically optimized for the preconcentration of nickel after forming a complex with diphenylcarbazone. The measurement output of the flame atomic absorption spectrometer was further enhanced by fitting a custom-cut slotted quartz tube to the flame burner head. The extraction method increased the amount of nickel reaching the flame and the slotted quartz tube increased the residence time of nickel atoms in the flame to record higher absorbance. Two methods combined to give about 90 fold enhancement in sensitivity over the conventional flame atomic absorption spectrometry. The optimized method was applicable over a wide linear concentration range, and it gave a detection limit of 2.1 µg L−1. Low relative standard deviations at the lowest concentration in the linear calibration plot indicated high precision for both extraction process and instrumental measurements. A coal fly ash standard reference material (SRM 1633c) was used to determine the accuracy of the method, and experimented results were compatible with the certified value. Spiked recovery tests were also used to validate the applicability of the method. [ABSTRACT FROM AUTHOR]

3-(chloro(2-methyl-1H-indol-3-yl)methyl)-2-methyl-1H-indole (MIMI) was chosen for separation and preconcentration of iron (III), copper (II), and zinc by solid-phase extraction (SPE). Ion-MIMI chelates are adsorbed onto synthesized graphene oxide (GO) as adsorbent, eluted with HNO3 and determined by flame atomic absorption spectrometry (FAAS). The adsorption mechanism of titled metal complexes on GO was investigated by using computational chemistry approach based on PM7 semi-empirical potential energy surface. The influences of analytical parameters were investigated. The interference effect of common cations tested did not interfere with the recovery of understudied ions. The preconcentration factor of 312.5 and the detection limits of 0.62, 0.28, and 0.05 ng mL−1 for iron (III), copper (II), and zinc, respectively, were obtained. The developed SPE method was successfully utilized for the determination of trace metal ions in different certified reference materials and real samples (including water, cheese, honey, tomato, leaves of spinach, and milk) by FAAS. [ABSTRACT FROM AUTHOR]

The concentration of cadmium in human tissues obtained on the basis of autopsies of non-poisoned Polish people ( n = 150), aged from 1 to 80 years, examined between 1990 and 2010, is presented. The following values were found in wet digested samples by flame atomic absorption spectrometry (FAAS) (mean ± SD, median, and range, μg/g of wet weight): brain 0.020 ± 0.031, 0.084, 0-0.120 ( n = 41); stomach 0.148 ± 0.195, 0.084, 0-1.25 ( n = 89); small intestine 0.227 ± 0.231, 0.130, 0-0.830 ( n = 39); liver 1.54 ± 1.55, 1.01, 0.015-9.65 ( n = 99); kidney 16.0 ± 13.2, 14.0, 0.62-61.3 ( n = 91); lung 0.304 ± 0.414, 0.130, 0-1.90 ( n = 25); and heart 0.137 ± 0.107, 0.140, 0.017-0.250 ( n = 4). Additionally, results ( n = 13 people, aged from 2 to 83 years, 63 samples) obtained by inductively coupled plasma optical emission spectrometry (ICP OES) between 2010 and 2015 are given. The obtained data on Cd concentration in the human body can be used to estimate the amounts occurring in 'healthy' people and those occurring in cases of chronic or acute poisonings with Cd compounds, which are examined for forensic purposes or to assess environmental exposure levels. [ABSTRACT FROM AUTHOR]

The authors describe the synthesis of a nanosorbent for fast magnetic solid phase extraction of trace levels of Ag(I), Au(III), Pd(II) and Pt(II). It consists of graphene oxide sheets modified with magnetite nanoparticles (mGO) coated with silica. This material was further modified with a polypyrrole-polythiophene copolymer via oxidative polymerization to end up with a material of the type mGO@SiO@PPy-PTh. Successful synthesis of the nanocomposite and its components was corroborated by FT-IR, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry and thermogravimetric analysis. The presence of nitrogen- and sulfur-containing functional groups on both sides of the nanocomposite sheets facilitates the formation of strong complexes between target (i.e. noble metal ions) and the surface of the sorbent. Following elution with thiourea-HCl, the ions were quantified by FAAS. Under optimized conditions, the lower limits of detection range from 0.1 to 1.0 μg L. The maximum sorption capacities are 49, 50, 45, and 50 mg g for Ag(I), Au(III), Pd(II) and Pt(II), respectively. The method was successfully applied to the extraction and determination of the analytes in wastewater (electroplating, radiological and photographical wastewater), sea water, and road dust. [ABSTRACT FROM AUTHOR]

The soluble forms of aluminum are now considered toxic or potentially toxic and they have been associated or related with neurological alterations, liver, bone, hematological disorders and breast cancer. To estimate the expanded uncertainty of a previously validated analytical method to quantify aluminum in tissues of Sprague Dawley rats through flame atomic absorption spectroscopy (FAAS) and electrothermal (ETAAS). The sources of uncertainty through an Ishikawa diagram have been established and the relative and combined standard uncertainty of the concentration of aluminum was determined from the curves of calibration, volumetric material and the dilution factor, repeatability, the purity of a standard aluminium and the concentration of aluminium in two certified reference materials (SRM-S-B and NIST 1566b). The estimates of each source of uncertainty were determined following the Eurachem/Citac Guide. It was possible to estimate the expanded uncertainty ( U) with a factor k = 2, and the results were of 3.709 mgL and 3.717 µgL of aluminium in tissues of Sprague Dawley rats with FAAS and ETAAS, respectively. There are few works in which the expanded uncertainty of an analytical method has been found to determine aluminum in tissue, however the results are acceptable and comparable against the results obtained with other methods that estimate the uncertainty of other metals and different matrix or tissue. [ABSTRACT FROM AUTHOR]

A solid phase extraction method based on the immobilisation of Penicillium chrysogenum on silica was developed for preconcentration and flame atomic absorption spectrometric determination of Pb(II). The immobilised sorbent was packed in a column to optimise the conditions for its quantitative sorption and desorption. Various parameters such as pH, type of eluent, sample and eluent flow rate and influence of others ions were systematically studied. Pb(II) was quantitatively sorbed at pH 4.0 at a flow rate of 2.0 mL min and eluted with 10.0 mL of 1.0 M HCl at 0.2 mL min flow rate. The devised procedure applied for Pb determination in tap water, an industrial effluent and sludge sample, black tea, spinach leaves and green beans (canned food) was reproducible, with a relative standard deviation of 0.8%. The method was validated by a BCR 701 standard lake sediment sample. The limit of detection and limit of quantification for Pb(II) were 7.16 and 23.88 μg L, respectively, with an enrichment factor of 100. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the elemental composition of black tea samples and their infusions in view of their geographical origin. In total, 14 elements were analyzed, 13 (Ca, K, Mg, Na, Mn, Fe, Zn, Cu, Cr, Ni, Co, Cd, and Pb) by flame atomic absorption spectrometry, and P by UV-Vis spectrometry, after mineralization of samples. It was found that K was the most abundant macroelement in the analyzed samples, whereas among microelements, the highest concentration was found for Mn. Based on the obtained data, the percentage of elements leached into the infusions as well as the daily elemental intake from tea were calculated. The daily intake from tea was compared to the recommended daily allowances (RDAs), and the highest percentages of the RDAs were found for Mn (15 %) and Co (10 %). To study the relations between elemental composition and country of origin of samples, factor analysis and cluster analysis were applied. These multivariate techniques proved to be efficient tools able to differentiate samples according to their provenance as well as plantation within the common regions. [ABSTRACT FROM AUTHOR]

In this study, the determination of Fe, Mn, and Zn by flame atomic absorption spectrometry (FAAS) was performed in nine bee pollen samples from different cities. The efficiency of acid digestion in bee pollen samples using nitric acid at different concentrations (3.5, 7.0, and 14.0 mol L) and hydrogen peroxide in a microwave oven was evaluated. The proposed procedure using nitric acid diluted to 3.5 mol L was effective for the digestion of all the pollen samples. The samples showed low levels of Fe. However, Mn and Zn were the elements which presented the highest concentrations in the samples. The bee pollen samples studied showed a great Mn and Zn contribution to the recommended daily intake (RDI) of the human diet, contributing with 71.7 and 15.1 %, respectively. The accuracy of the measurements by FAAS was evaluated by adding aliquots of the elements in the digestates. Recoveries obtained ranged from 89 to 106 % for Fe, 94 to 100 % for Mn, and 88 to 108 % for Zn. [ABSTRACT FROM AUTHOR]

This study concerns application of flame atomic absorption spectrometry (FAAS) in assessment of macro- and microelement and toxic metal levels (Mg, Ca, K, Na, Mn, Cu, Fe, Zn, Cr, Ni, Co, Cd and Pb) in dark (Pu-erh) and fruit tea leaves and their infusions. Phosphorus was also determined in the form of phosphomolybdate by spectrophotometric method. The reliability of the method was checked using three certified reference materials. The results of analysis were in agreement with the certified values, with analytical recovery ranging from 86 to 113 %. Significant correlations ( p < 0.001) were found between concentrations of P, Zn, K, Ni, Fe, Co, Cr, and Pb in Pu-erh tea, whereas in fruit tea, such interdependences were found between Mg, Fe, P, Ni, and Co. Kruskal-Wallis test results have related differences in Pu-erh tea quality as well as technological processing of fruit tea to their mineral composition. In order to characterize tea elemental content, chemometric techniques such as factor analysis (FA) and cluster analysis (CA) were used. Their application allowed on differentiation of samples in view of the fermentation type, technological processing, and overall quality. [ABSTRACT FROM AUTHOR]

In the current study, a new ultrasonic-assisted cloud-point extraction (UA-CPE) method for the preconcentration and determination of antimony and tin in the selected food and beverages was developed by flame atomic absorption spectrometry (FAAS). The method is based on the fact that formation of the stable ternary complexes of Sb(III) and Sn(IV) with 2-( 2, 4- dihydroxyphenyl)- 3, 5, 7- trihydroxychromen- 4- one (morin) in presence of cetyltrimethylammoniumbromide (CTAB) as both sensitivity improvement auxiliary ligand and counter ion, and then extraction into the micellar phase of poly( ethylene glycol- mono- p- nonylphenylether (PONPE 7.5) as extracting agent at pH 8.5. Under the optimized conditions, the calibration curves for Sb(III) and Sn(IV) were rectilinear with changing calibration sensitivities in ranges of 0.1-140 and 0.1-225 μg L, respectively. The limit of detection for both Sb(III) and Sn(IV) was 0.03 μg L with sensitivity enhancement factor of 114.5 and 110.6, respectively. The precision as a relative standard deviation (RSD) for Sb(III) and Sn(IV) is in range of 2.3-5.2 and 2.6-5.4 %, respectively. The trueness of the method was verified by analysis of certified reference materials (CRMs). The method was successfully applied to determination of antimony and tin in the selected food and beverage matrices. [ABSTRACT FROM AUTHOR]

A new procedure for the determination of chromium species in polluted environmental samples by flame atomic absorption spectrometry was developed in this work. A new material containing 1,5-diphenylcarbazone included in a polymeric matrix was prepared and employed as a solid-phase extraction material for selective separation of Cr(III) ions under dynamic conditions. Chromium(III) ions were retained on this sorbent with high efficiency and repeatability (95 %, RSD = 1 %) from solutions with pH 9.0. The quantitative recovery of analyte was obtained with 0.1 mol L EDTA. The concentration of Cr(VI) ions was calculated from the difference between the concentration of total chromium and Cr(III) ions. The prepared sorbent exhibits good chemical and mechanical stability, sorption capacity and selectivity towards Cr(III) ions in the presence of Cu(II), Ni(II), Mn(II) and Ca(II) ions. The accuracy of the separation method was proved by analysis of reference material of wastewater RES 10.2. The developed procedure was applied for chromium speciation analysis in municipal sewage samples. [ABSTRACT FROM AUTHOR]

In the present study, levels of metal contamination caused by former lead mining area were figured out. For this purpose, Pb, Cd, Cu, Ni, and Mn were determined not only in sediment samples taken from different places of the mining area but also in some plants taken around the mining place. In the digestion of plant samples, dry ashing procedure was applied. Flame atomic absorption spectrophotometer (FAAS) was used in the determination of analytes of interest. All the parameters in digestion and detection procedures were optimized to obtain efficient digestion and high sensitivities for analytes. Standard addition and direct calibration methods were applied to find whether there was any matrix interference to affect the determination of analytes. Mn concentration was found to be the highest for each sample analyzed. Lead concentration was found to be between 41 and 249 mg/kg in soil/sediment samples and between 2.2 and 1003 mg/kg in plant samples. The highest contamination levels for all of the analytes with the exception of Cd were found in current sediment sample. [ABSTRACT FROM AUTHOR]

A new amino-functionalized FeO-graphene oxide nanocomposite (AF-FeO-GO) was synthesized. The properties were characterized by Fourier-transform infrared spectrometry and scanning electron microscopy. The obtained adsorption results showed that the AF-FeO-GO had great adsorptive ability toward Cu(II). Based on these, an effective magnetic solid-phase extraction (MSPE) procedure coupled with flame atomic absorption spectrometry for the pre-concentration and determination of Cu(II) in food samples was developed. Various experimental parameters that could affect the extraction efficiency were investigated in detail. Under optimum conditions, enhancement factor of the method for Cu(II) was found to be 95.08. The proposed method was successfully applied for the analysis of food samples with recoveries ranging from 97.2 to 99.1 % and a correlation coefficient ( R) of 0.999. Good linearity was obtained, ranging from 1 to 100 µg L. The limit of detection and precision of the method were 0.9 ng mL and 1.23 %, respectively. It was confirmed that AF-FeO-GO nanocomposite can be a highly effective MSPE adsorbent used for trace Cu(II) analyses. [ABSTRACT FROM AUTHOR]

Calotropis procera is a medicinal plant used traditionally in animal and human medicine for its digestive and anti-asthmatic effects. In the present study, antioxidant activity and mineral element contents of the leaves and flowers of C. procera were determined. Different extraction methods that include ethanol, chloroform, and water extraction were used to prepare extracts from the leaves and flowers of this plant. Diphenyl picrylhydrazyl (DPPH) method for antioxidant activities and flame atomic absorption spectrometry (FAAS) with microwave digestion for mineral element contents were performed. Aqueous extract of flower was the most potent radical scavenger (IC of 85.58 ± 9.41 μg/ml) followed by ethanol extract of flowers (IC of 142.95 ± 10.01 μg/ml). In addition, the antioxidant activities of all the flower extracts were significantly higher than that of the leaves ( P <0.05). Also, high concentrations of K (196.50 ± 10.02 μg/mg) and Ca (108.23 ± 5.30 μg/mg) and low concentrations of Na, Cr, and Fe (0.87 ± 0.04, 2.44 ± 0.17, and 2.63 ± 0.21 μg/mg, respectively) were demonstrated in the leaves of C. procera. Our results provide a support for the use of C. procera in traditional medicine and may be clarified as the cause of its beneficial effects. [ABSTRACT FROM AUTHOR]