Copper-chitosan modified with Graphene oxide adsorbent for dispersive micro solid phase extraction of traces nickel from water and food samples

The current study presents a new insight into separation of Ni (II) by preconcentration method from water and food samples prior to atomic flame absorption spectrometry analysis. A Cu-chitosan modified Graphene oxide adsorbent was used for micro-solid phase extraction of Ni (II). The synthesized nanocomposite was subjected to characterization by FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (Field emission scanning electron microscope), SEM-EDX (Scanning electron microscopy-energy dispersive X-ray analysis), TGA (thermogravimetric analysis) and BET (Brunauer-Emmett-Teller) analysis to confirm the qualitative characteristics of the material prior to extraction process. Crucial analytical parameters such as pH, adsorbent dosage, adsorption studies and sample volume were investigated and optimized. The quantitative recoveries (95 %) and relative standard deviation below 5 % were obtained. The Limit of detection (LOD) and Limit of quantification (LOQ) were 0.072 mg kg−1 and 0.239 mg kg−1 respectively. To determine the greenness of the process two analytical parameters were tested, namely, analytical GREENness and AGREEprep, resulting in 0.73 and 0.70 respective grades. The proposed method presents a moderate eco-friendly and facile process. The preconcentration factor obtained for Ni (II) was 40. To validate the effectiveness of this work, the dµ-SPE method was applied to two different standard reference materials, BCR-701 lake sediment (Belgium) and TMDA-54–6 (Canada) certified water reference material

Differential expression of VGLUT1, GAD65, GAD67, and MAP2 in the retina of hibernating Anatolian ground squirrel<i> (Spermophilus</i><i> xanthoprymnus)</i>

The Anatolian ground squirrel (Spermophilus xanthoprymnus) offers a valuable model for investigating neuroadaptive processes in the retina during hibernation. This study aimed to assess the expression of vesicular glutamate transporter 1 (VGLUT1), glutamic acid decarboxylase (GAD) isoforms GAD65 and GAD67, and microtubule-associated protein 2 (MAP2) in the retina during pre-hibernation and hibernation states. Retinal tissues were analyzed using immunohistochemistry and densitometric quantification. VGLUT1 expression remained stable in the outer plexiform layer (OPL) but was significantly reduced in the inner plexiform layer (IPL) during hibernation, indicating a selective downregulation of excitatory transmission between bipolar and ganglion cells. GAD65 showed widespread distribution across retinal synaptic layers and optic fibers in pre-hibernation but declined markedly during hibernation, consistent with reduced activity-dependent GABAergic signaling. In contrast, GAD67 immunoreactivity increased in the inner nuclear layer, suggesting a shift toward sustained basal inhibitory tone that may support synaptic stability during metabolic suppression. MAP2 immunoreactivity increased in the inner nuclear layer (INL) and outer plexiform layer (OPL) but decreased in the photoreceptor layer (PRL) during hibernation. This shift in distribution suggests cytoskeletal reorganization in second-order neurons and reduced physiological activity in photoreceptor terminals under metabolic suppression. Together, the modulation of excitatory (VGLUT1), inhibitory (GAD65/67), and cytoskeletal (MAP2) markers suggest that the hibernating retina undergoes structural and functional adaptations aimed at preserving neural circuitry under metabolic suppression

Aromatherapy Experiences of Intensive Care Nurses Regarding Sleep and Fatigue: A Phenomenological Study

Background: Critical care nurses frequently experience fatigue and sleep problems. Some nurses have used aromatherapy as a complementary approach to cope with these challenges. Aim: This study aimed to examine the personal experiences of intensive care nurses regarding the use of aromatherapy for sleep and fatigue. Study Design: A qualitative phenomenological approach was adopted, using purposive sampling. Ten intensive care nurses working in a Level 3 intensive care unit who met the inclusion criteria and agreed to participate were interviewed individually. Firsthand experiences with aromatherapy were explored in depth to obtain detailed data. Data were collected using a semi-structured interview form. With participants' consent, identifiers were anonymized and coded as ‘P1, P2, P3’. The interviews were audio-recorded, transcribed verbatim, and codes were derived directly from the participants' narratives. These codes were organised into categories and then grouped into overarching themes, which were analysed using inductive content analysis. Results: The central theme was ‘Personal Aromatherapy Experiences of Intensive Care Nurses and Their Perceptions and Impacts of Fatigue and Sleep Problems’. Within this theme, intensive care nurses shared their personal aromatherapy experiences and their perceptions of fatigue and sleep problems. Based on their personal experiences, nurses identified several factors contributing to sleep and fatigue problems, including irregular diet, 24-h shift schedules, education, alternate-day care, long working hours, family life, burnout, chronic illness, irregular sleep patterns, the debilitating nature of disease, night shifts and the intensive care environment. To address these issues, nurses reported using various aromatherapy oils, such as lavender, chamomile, orange, lemon, eucalyptus, jasmine, rose and violet. They indicated that aromatherapy increased energy, promoted relaxation, reduced pain, stress and fatigue, and facilitated falling asleep, highlighting its positive effects on their well-being and work-life balance. Conclusion: Interviewed intensive care nurses reported that aromatherapy helped them cope with fatigue and sleep difficulties and supported their well-being in high-risk work environments. Relevance to Clinical Practice: Aromatherapy may offer a supportive coping mechanism for fatigue and sleep disturbances among intensive care nurses. Randomised controlled trials with evidence-based data on this topic can be planned. Therefore, nurses in healthcare institutions can be supported with evidence-based strategies, improvements in working conditions and training in aromatherapy applications in intensive care units

Unconventional bioprinting modalities for advanced tissue biofabrication

Bioprinting has been widely used to fabricate three-dimensional constructs for various applications. However, conventional bioprinting modalities face challenges such as low resolution, poor repeatability, limited speed, and scalability constraints. To overcome these limitations, unconventional bioprinting modalities have been actively developed, utilizing electric fields, acoustic waves, magnetic forces, light, smart materials, and microfluidics to advance bioprinted tissues. This Review explores various unconventional bioprinting modalities, which significantly improve upon conventional counterparts to create complex, scalable heterogenous tissue constructs. In addition, emerging bioprinting methods, utilizing the principles of conventional or unconventional bioprinting modalities with new concepts integrated, such as embedded bioprinting, cryobioprinting, microgravity bioprinting and 4D bioprinting, were discussed. Key applications include functional tissue engineering, disease modeling, and organoid development, with future directions focusing on artificial intelligence-driven bioprinting, multimodal biofabrication, and intraoperative bioprinting to improve scalability and clinical translation. By integrating interdisciplinary innovations, unconventional bioprinting offers new opportunities to advance tissue biofabrication technologies

Effect of Plain, Concave and Convex Winglet Geometry on Wing Performance at Various Cant Angles

The wingletslocated at aircraft wing ends are used to increase the aerodynamic performanceand reduce fuel consumption by regulating negatively affecting the performanceat the wings end. Therefore, aircraft wings have a critical importance onaerodynamic efficiency. The most efficient winglet model should be used in eachof the flight positions. This study is aimed to investigate the effects ofconcave, convex, and plain winglet geometry on wing performance. The effects ofplain, concave and convex winglet models with cant angles of 30, 45, and 60°were experimentally investigated at the angles of attack ranging from 0 to 20°.The aerodynamic lift and drag coefficients generated by each design weremeasured in wind tunnel tests conducted at a Reynolds number of 2.5×105,and the effect of the winglet's shape on wing performance was compared. Thedata obtained reveal that various wingtip designs have significant effects onthe aerodynamic properties of the wing. At low, moderate and high angles of attack, thehighest lift is achieved with the 30° cant anglewinglet. The best results for all winglet models in termsof the aerodynamic quality were obtained in the plain winglet model.Furthermore, the aerodynamic quality generally increases with decrease in thecant angles. It is anticipatedthat these findings, obtained from winglet models with various geometricdesigns, could contribute to the development of more efficient winglet geometry.</p