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The mechanical properties of natural and man-made fibres ultimately govern the robustness of products. Examples range from textiles to composite materials for mechanical parts in emerging technological applications. An accurate determination of the mechanical properties of microscopic single fibres is therefore important. Today, macroscopic mechanical techniques, such as tensile testing, are commonly employed to obtain this information. However, a relatively high dispersion of results is often encountered due to a relatively long sample size. As an alternative to tensile methods, we demonstrate here micromechanical techniques to accurately measure the flexural modulus and strength of micrometre-sized diameter fibres without the need of force sensing. To demonstrate our ideas, we use the example of single natural fibres ( Linum Usitatissimum ). The flexural modulus of the single fibres is first accurately measured in the low deflection regime of an inclined bending cantilever in an original setup. The flexural strength of the single fibres is then measured in the high deflection regime of a bending cantilever. Interestingly, the novel measurements have allowed the authors to quantify the flexural strength of two different failure modes in flax fibre, enabling a contribution to plant mechanics.

Flax fibres are a natural, sustainable product which have applications ranging from textiles to composite materials. A process known as ‘retting’ is required to facilitate the mechanical extraction of flax fibres from their associated stems. The goal of retting is to break down the binding material (pectin) holding the fibre bundles to the core and epidermis of the stem, not the pectin which holds the single fibres together which form long, practical ‘technical’ fibres. For natural dew retting, there is therefore an optimum retting period: insufficient retting renders fibre extraction difficult and leads to low yield, whereas excessive retting can lead to poor technical fibre quality. For centuries, the timing of the retting termination has been evaluated by artisanal means. Today, modern technology enables one to envisage tools that indicate optimal retting. Here, we demonstrate the development of a smart tool combining mechanics, digital microscopy, and image analysis. The cracking of the outer tissue of the flax stems, due to mechanical torsion applied to the stems by the tool, is quantified using optical microscopy and image analysis, and is demonstrated to serve as an observable indicator of the degree of retting of the stems.

Cadmium (Cd) is a dangerous heavy metal that is non-degradable in the environment. Many organs can accumulate Cd and adversely affect organ function and health. Cd is considered as a teratogenic and embryotoxic agent. This study aims to evaluate the teratogenicity of Cd at concentrations lesser than the permissible and its effects on the heart during chick embryogenesis. Fertilized eggs of the chick Gallus domesticus were divided into; control, saline injected and four experimental groups injected with single doses of 5, 25, 50 or 75 µM of CdCl2. Histological observations of the heart before hatching and the cardiomyocytes after hatching were recorded. Morphometric measurements of heart chambers were achieved at 3, 4 and 6 days of incubation. Electrocardiograph and respiratory rate were recorded at tenth day. Different cardiac problems had been brought on by Cd. In comparison to controls, the heart looked much larger, and in certain cases, growth retardation was seen. Degeneration in heart walls and malformations of dorsal aorta were noticed. Morphometrically, the width and wall thickness of heart chambers showed significant changes. Heart beats and respiratory rate significantly decreased compared to control. The cardiotoxic effect of Cd on heart compartments structure and function was dose dependent. One of Cd toxicity is its ability to induce cellular oxidative stress. The heart in particular is sensitive to oxidative stress. Cardiac oxidative stress might intensify heart failure and promote disease progression. Calcium is one of the components that is needed for normal heart work. Cd might interfere with calcium metabolism by removing it from the body.

Air-to-ground interference poses a critical challenge in integrating unmanned aerial vehicles (UAVs) into cellular networks. In downlink scenarios, UAVs can withstand significant interference from co-channel base stations (BSs) due to the guaranteed line-of-sight (LoS) connection with ground users. Our research focuses on power optimization in BSs and applying green energy principles to pave the way for more sustainable and energy-efficient BSs within UAV-integrated wireless systems. To this end, this paper investigates a downlink UAV communication scenario in which the intelligent reflecting surface (IRS) is mounted on the UAV to practically nullify the interference originating from the co-channel BSs. We formulate the IRS beamforming matrix to reduce transmit power by optimizing passive beamforming for IRS elements, incorporating adjustments to phase shifts and amplitude coefficients while considering the positioning of the UAV. The proposed optimization problem is non-convex, and thus a successive convex approximation (SCA) method is adopted to convert all constraints to a quadratic approximation. Simulation results demonstrate that the proposed SCA algorithm provides an efficient transmit power minimization approach with low computational complexity for large IRS since it achieves close-to-optimal performance, and significantly outperforms conventional systems without IRS. In interference scenarios and with different numbers of IRS meta-atoms, the proposed algorithm achieves a power reduction of approximately 8 and 13 dBm, while maintaining the same required signal-to-interference-plus-noise ratio. [JJCIT 2025; 11(2.000): 184-196]

Dew retting of flax stems is a key agricultural process which facilitates fiber extraction from parent stems. If sensors are to be developed to monitor the degree of retting for optimal fiber extraction, then stem characteristics such as water uptake and loss need to be accurately known. Here, the moisture uptake and drying behavior of short flax stem samples in different degrees of dew retting is studied. Their drying is characterized in laboratory conditions following simulated light and heavy rainfall. The data were accurately fitted with the Page model of moisture loss. It was observed that the drying rate constant of small flax stem samples is smaller for simulated light rain compared to simulated heavy rain. Also, over-retted stem samples dry more rapidly compared to under-retted samples. The findings suggest that this is due to the degradation of the external tissue of the stems observed in the over-retted samples. The results could be useful for laboratory testing of flax stems and designers of emerging technological sensor-based tools used to monitor the degree of retting in controlled conditions.

Laparoscopic sleeve gastrectomy (LSG) is considerably utilized as a bariatric method for treating morbid obesity through the reduction of stomach volume. The present study attempted to assess the volumetric changes of the gastric reservoir 1 year after LSG using multi-slice spiral computed tomography (MSCT) as well as to verify their association with weight loss. The current study is a prospective study of 40 consecutive morbid obese patients managed with laparoscopic sleeve gastrectomy. All patients were referred to abdominal MSCT besides volumetric measurement of the gastric pouch 1 month and 12 months postoperatively after the LSG. There were statistically substantial differences throughout the whole period of follow-up ( p value ≤ 0.05) regarding the ratio of excess weight loss, weight loss, and decreased BMI, in addition to the ratio of excess body mass index loss (% EBMIL) after LSG. Substantial elevation of the overall volume of the gastric reservoir (82.9 SD11 and 171.6 SD23.6 ml at 1 and 12 months, respectively) was observed. However, the current findings did not demonstrate any significant association ( r  = 0.131, p  = 0.491) between excess weight loss percentage and the increase in gastric reservoir volume 1 year postoperatively. Sleeve dilatation is a common finding following sleeve gastrectomy (SG) even after conducting a narrow gastric pouch, yet dilatation was not correlated with insufficient weight loss after 1 year postoperatively. Trial registration number: NCT04880902.

Background Effective pain management in elderly patients is crucial for quality of life, yet cultural and institutional factors can significantly impact care delivery, particularly in Arab healthcare settings. Aim To explore the barriers and facilitators to effective pain management in elderly Arab patients from the perspective of nurses. Methods A qualitative descriptive study was conducted with 12 registered nurses from various departments at Tanta University Hospitals, Egypt. Data were collected through semi-structured interviews, observations, and document analysis. Content analysis was used to identify themes and subthemes. Results Five main themes emerged: (1) Cultural Barriers to Pain Expression, including stoicism and religious beliefs; (2) Institutional Barriers to Pain Management, such as resource limitations and time constraints; (3) Facilitators to Effective Pain Management, including family support and nurse adaptability; (4) Interdisciplinary Collaboration, emphasizing teamwork and education; and (5) Emotional and Professional Rewards for nurses. Cultural factors often led to underreporting of pain, while institutional constraints hindered thorough assessments. Nurse adaptability and family support, when present, facilitated better pain management. Conclusion The study reveals complex interplay between cultural, institutional, and professional factors influencing pain management in elderly Arab patients. Findings suggest the need for culturally sensitive pain assessment tools, enhanced nurse education in pain management, and policies promoting family-centered care and interdisciplinary collaboration. Implications Results can inform the development of culturally appropriate pain management strategies and policies in Arab healthcare settings, potentially improving care quality for elderly patients.

Metaphors have long been recognized as powerful tools that shape our understanding of the world. In the context of the Israeli-Palestinian conflict, metaphors play a crucial role in shaping perceptions and attitudes towards the conflict. This research explores the connection between Lakoff and Johnson's Conceptual Metaphor Theory and the role of metaphor in the Israeli-Palestinian conflict from a cognitive linguistic perspective. The study focuses on the use of metaphorical language by Israeli Prime Minister Benjamin Netanyahu and Palestinian Authority President Mahmoud Abbas during the period of April 2023 to September 2023. Applying Lakoff and Johnson's approach, the research aims to uncover the specific metaphors employed by these leaders to frame the conflict in a manner that serves their respective interests and narratives. The research objective is to gain a more nuanced understanding of how metaphors shape the discourse surrounding the Israeli-Palestinian conflict. By exploring the cognitive and linguistic strategies used by political actors, the study seeks to elucidate the underlying mechanisms through which metaphors can be leveraged to construct, perpetuate, and potentially transform the conflict narrative. The findings of this research are expected to offer valuable insights into the role of language in shaping perceptions, identity formation, and the justification of political actions within the context of the Israeli-Palestinian conflict. The analysis of metaphorical patterns used by the key stakeholders will illuminate how cognitive frames are established, maintained, and potentially challenged, ultimately contributing to a more comprehensive understanding of the conflict's dynamics.

Dysmenorrhea is a highly prevalent gynecological problem that may compromise the girls' quality of life. Disabled girls might experience menstruation both differently and more negatively compared to non-disabled girls. The current study aimed to investigate the prevalence of dysmenorrhea and its associated symptoms amongst disabled girls. A cross-sectional study was conducted among 93 adolescent girls with disabilities. An interviewer questionnaire was used to inquire about personal characteristics, menstrual history, knowledge and attitudes of dysmenorrhea, symptoms that coincide with menstruation, and methods used by girls to manage their menstrual pain. WaLIDD scale was used to assess pain intensity during menstruation. About 97% of the studied disabled girls suffered from moderate or severe degrees of menstrual pain. Using methods to mitigate the pain was reported by 72%. Herbal drinks and analgesics were the most frequently used methods. School absenteeism because of dysmenorrhea was reported by 36%. Most of the girls (87.1%) had a poor knowledge level. The most frequent disabling/severe symptoms that coincide with dysmenorrhea were general aches, dizziness, and fatigue. Increased perception of symptoms coinciding with menstruation was a significant predictor for severe dysmenorrhea (AOR = 3.279, 95%CI = 1.028:1.088). Most disabled girls suffer from moderate to severe dysmenorrhea. Increased symptoms associated with menstruation positively affect severe dysmenorrhea perception. Girls with disabilities need better access to menstrual health education. Tailored reproductive health programs should be provided for blind and deaf girls for assurance and proper practice to manage symptoms associated with menstruation, especially pain, to mitigate their disabling impact.

Purpose We assessed the efficacy of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in patients with low-grade isthmic spondylolisthesis. Methods We included 24 symptomatic patients who underwent MIS-TLIF between December 2017 and December 2020. Patients were followed up clinically by the Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) for back and VAS for leg pain, as well as radiological radiographs after 6 weeks, 6 months, and at final follow-up (at least 12 months). Measured parameters included C7 sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), Meyerding slip grades, lumbar lordosis (LL), L1–L4 angle, L4–S1 angle, and segmental lordosis (SL) of the affected segment. The mismatch between the PI and LL was also measured. Results VAS for back, VAS for leg pain, and ODI significantly improved postoperatively (all p  < 0.001). We observed significantly decreased mean values of PT and slip percentage and increased mean values of SS and LL (all p  < 0.05). We observed a significant reduction in L1–L4 lordosis and a significant increase in L4–S1 lordosis. The final PT, SS, and LL (total and L1–L4) were significantly higher in group III patients ( n  = 15) than the values of group II patients ( n  = 9). None of the patients became unbalanced postoperative, and all patients had a normal matching between the PI and the LL postoperatively. Conclusions MIS-TLIF is a safe procedure for managing low-grade isthmic spondylolisthesis with significant improvement in clinical and radiological outcomes. It can correct and maintain a proper spinopelvic alignment.