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Herein, we present a new eco-friendly microextraction method based on the magnetite/multi-walled carbon nanotubes reinforced and natural deep eutectic-filled hollow fiber solid/liquid phase microextraction, abbreviated as HF-SLPME, combined with HPLC–DAD analysis. This method has been developed to determine trace levels of phthalate esters, including diethyl phthalate, benzyl butyl phthalate, and di-iso-butyl phthalate in urine, blood plasma, tap water, and groundwater samples. The natural deep eutectic solvents were prepared using terpenoid-derived natural compounds containing menthol and camphor in various ratios. The HF-SLPME device was constructed by reinforcing and immobilizing the synthesized Fe3O4-MWCNTs within the pores of a 2.5 cm segment of hollow fiber microtube through ultrasonication, followed by filling the lumen with the natural deep eutectic solvent with both ends heat sealing. The extraction process was conducted in direct immersion mode. Values of crucial variables for HF-SLPME were optimized through a multivariate methodology based on a central composite design, with 30 extraction tests performed to determine the best conditions. The method exhibited good linearity (correlation coefficients R2 > 0.996) over a dynamic range lower than 0.927–103 µg L−1. The results show that the limits of detection/quantification for the chosen PEs ranged from 0.19 to 0.27/ 0.65 to 0.92 µg L−1 with enrichment factor˃ 37.24. As evidenced by intra- and inter-day precisions, satisfactory reproducibility was achieved with relative standard deviations (RSDs) below 3.7% and 5.1%, respectively. The recoveries of the selected phthalate esters from spiked real samples ranged from 88.4 to 111.1%, with relative standard deviations between 2.3 and 6.5%. This HF-SLPME-HPLC–DAD method offered a new, cost-effective, sensitive microextraction approach for determining and quantifying phthalate esters in aqueous samples with complex matrices. [ABSTRACT FROM AUTHOR]

Background: Malnutrition remains a global health issue, endangering the lives of millions of children, especially in developing nations. It profoundly affects a child's physical and mental development, leading to severe and often irreversible consequences. Objectives: This study aims to assess the knowledge, attitudes, and practices of mothers with acutely malnourished children concerning child feeding and the prevention of malnutrition. Subjects and Methods: A cross-sectional hospital-based study was conducted involving 139 mothers with acutely malnourished children admitted to the malnutrition ward at Mohammed Al-Ameen Hamid Pediatric Hospital between May 2022 and December 2022. Data were collected through direct interviews with the surveyed mothers utilizing a validated, structured questionnaire. Analysis of data was performed using SPSS software version 20. Results: The study revealed that 78.4% of mothers possessed adequate knowledge, 80.6% exhibited favorable attitudes, and 55.4% demonstrated good child-feeding practices and malnutrition prevention practices. A significant correlation between mothers' education and practice was identified (P = 0.025). Furthermore, data analysis highlighted the significant association between mothers' knowledge and attitude (P = 0.007), mothers' knowledge and practice (P = 0.006), and mothers' attitudes and practice (P = 0.033). Conclusion: Most mothers exhibited sufficient knowledge and positive attitudes regarding child feeding and malnutrition prevention; however, there is a need to translate this awareness into improved practices. [ABSTRACT FROM AUTHOR]

The concentration level of urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), an oxidative stress biomarker for various diseases especially cancer, has been attracted as a pathway suitable for diagnostic purposes. Determination of urinary 8-OHdG is challenging due to its low level within a complex matrix. In this study, a new approach of solid/liquid phase microextraction technique prior to high-performance liquid chromatography diode-array detection (HPLC-DAD) analysis was developed for the determination of trace levels of 8-OHdG in urine samples. The solid/liquid phase microextraction device was constructed by reinforcement of multi-walled carbon nanotubes into the pores of a short segment 2.5 cm of hollow fiber microtube with two ends heat sealed. Based on the optimized procedure, the selected analyte was extracted from an acidic sample solution (10 mL adjusted at pH = 5) into the five extraction devices. After the extraction period (30 min), the 8-OHdG was eluted from the extraction device using methanol (350 µL) under ultrasonication for 5 min. The analytical performance of the method in synthetic urine samples showed good linearity (R 2 > 0.999) with the limits of detection of 0.85 ng mL−1, and extraction recovery > 92.36%. The developed microextraction technique exhibited a confident sensitivity, feasible operation, and simplicity in comparison with other published methods and was valid to determinate trace 8-OHdG in urine cancer patients' samples by using a cheap and commonly available HPLC-DAD instrument. [ABSTRACT FROM AUTHOR]

In this paper, the design and the implementation of a stabilising feedback law for an engine throttle valve system are investigated while taking into account the digital communication over the vehicle network. In particular, the digital communication between sensors, controller, and actuators is studied using the event-triggered theory. Considering the sampled-data nature of the closed-loop system, the emulation approach is used to synthesise the control law to stabilise the plant in the continuous-time domain. Next, we provide a systematic methodology to derive, both, time-triggering and event-triggering rules such that the closed-loop stability is preserved. The approach is illustrated by simulation on the dynamic model of the throttle valve system. [ABSTRACT FROM AUTHOR]

Background: Apart from the wasted resource, canceled tests cause delay of test results thus affecting patient care. The study aimed to identify the reasons for the test cancellation of samples received in a blood bank laboratory and determine the improvement target. Methods: The study retrospectively reviewed the canceled tests in a blood bank laboratory of a hospital in Hail, Saudi Arabia, from January 2017 to December 2020. Records of the canceled test taken from the quality assurance database were utilized to identify the various reasons. Results: A total of 2,017 (2.7%) test cancellations were recorded in the 4-year study period with increasing rates noted. The two primary reasons were specimen quality issues (61.9%) and problems related to test orders (33.9%). The main reason for test cancellation was clotted specimen (48.5%) followed by incorrect test order (15.6%) and duplicate test order (13.9%). Statistically, a significant difference exists between the annual rates and reasons of cancellation, X² (6, n = 2,017) = 83.24, p < 0.001. Conclusions: Test cancellations due to various reasons remain a significant challenge for clinical laboratories. Detailed analyses on these major reasons can aid in displaying an effective approach to decrease the cancellation rates. Harmonization among inter-professional health workers concerning specimen collection and handling, and involving clinical laboratory personnel could minimize laboratory errors and avoid test cancellations. [ABSTRACT FROM AUTHOR]