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In this paper, we explore the spectral properties of unbounded generalized Fredholm operators acting on a non-reflexive Banach space X. The results are formulated in terms of some topological conditions made on X or on its dual X * . In addition, we introduce the concept of the so-called g-g-Riesz linear operators as an extension of Riesz operators. The obtained results are used to discuss the incidence of the behavior of generalized essential spectra. Furthermore, a relation between the generalized essential spectrum and the left (resp. the right) essential spectrum by means of g-Riesz perturbation is provided. [ABSTRACT FROM AUTHOR]

A multi-layer structure by sandwiching rigid cellular PVC (polyvinyl chloride) foam between two GFRP (glass-fibre reinforced plastic) faces is studied in order to investigate the sample edge effects on fatigue life of the sandwich structure. Therefore, a new geometry of specimen is developed based on numerical simulation approach. Compared to the results given by the ASTM C393 standard, the experimental study was confirmed that edge effects are leading to early failures as the shear stresses concentration was shifted from the new geometry. An optimal prediction of fatigue life of foam-based sandwich has been established during bending fatigue test. The different failure modes were followed by microstructural analyses to better explain the global behaviour of the structure. [ABSTRACT FROM AUTHOR]

The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI. [ABSTRACT FROM AUTHOR]

After having gained prominence in the late 20th century, corporate social responsibility (CSR) has emerged as a critical business aspect, adopted widely across the corporate landscape. Although family firms play a significant global role, research on their relationship with CSR performance remains sparse and inconclusive. This paper seeks to bridge this gap by employing the primary classification of family firms, the socioemotional wealth perspective, and its FIBER model to examine their influence on CSR performance. The focus is on Canadian public companies listed on the S&P/TSX Composite Index from 2014 to 2022. Utilizing the NBC Canadian Family Index, the findings suggest that family firms exhibit superior CSR performance compared to their non-family counterparts. Further analyses indicate that family firms with greater control and influence by family members, those named after the family, those with strong emotional ties, and first-generation family firms tend to have enhanced CSR performance. By developing a socioemotional wealth score through FIBER dimensions to classify family firms, this study underscores the association of family firms with higher CSR performance, validating the robustness of the results. [ABSTRACT FROM AUTHOR]

Introduction Nursing is highly demanding and stressful profession. Therefore, maintaining and improving psychological wellbeing among nurses seems essential to have a better life satisfaction and a better productivity. Objectives The aim of this study was to assess the relationship between mental health and life satisfaction among nurses. Methods The study was conducted in a group of active nurses from Hedi Chaker hospital in Sfax- Tunisia. Standardized questionnaires were used, including the general health questionnaire (GHQ-28) and the satisfaction with life scale (SWLS). Results A total of 100 (males = 40; females = 60) nurses participated in this study. The mean age was 50.20 ±7.20 years. The average of job tenure was 25.25 ± 9.70 years. The majority of participants (66.7%) reported having chronic diseases. Rotating shifts work was noted in 72.50% of cases. Average scores for the GHQ-28 and the SWLS were respectively 30.66 ± 11.07 and 21.61± 6.23. The presence of chronic conditions was associated with psychological distress (higher GHQ-28 scores) (p = 0.01). Life satisfaction score was positively correlated with age (r= 0.29, p= 0.023), whereas it was negatively correlated with GHQ-28 scores (r= -0.36, p= 0.01). Low life satisfaction (SWLS scores between 5 and 14) was significantly associated with three domains of the GHQ-28: somatic symptoms (p = 0.008), anxiety (p = 0.001) and social dysfunction (p = 0.01). Conclusions According to our study, low life satisfaction was associated with psychological disorder. Hence, nurses need support and subsequent interventions in order to improve psychological wellbeing and life-satisfaction. Disclosure No significant relationships.

Introduction Tinnitus is an auditory perception of a “phantom” nature with highly changing features. There is an established correlation between anxiety, depression, sleep disorders and tinnitus. Objectives To evaluate the prevalence of sleep disorders and emotional disorders during tinnitus and their correlation to the severity of the symptomatology Methods A descriptive cross-sectional study of 60 patients consulting for subjective tinnitus. For each patient we collected epidemiological data and performed an ENT and general examination, an audiometric and psychoacoustic evaluation and a psychometric evaluation. To evaluate the severity of the tinnitus we used the visual analog scale VAS and the subjective tinnitus severity test (STSS). Disability was assessed by the Tinnitus Handicap Inventory (THI). Anxiety and depression were assessed by: the Hamilton anxiety Rating scale and the Beck depression inventory. Results The prevalence of emotional disorders was: 21.7% for depression, 48.33% for generalized anxiety disorder, 11.67% for dysthymia, 5% for agoraphobia 16.67% for panic disorder and 1.67% for social phobia. The intensity of tinnitus was correlated with more panic disorder (p=0.008). Subjective severity of tinnitus was correlated with disability (p=0.0001), awareness of tinnitus in relation to sleep duration (p=0.006) and disturbed sleep (p=0.047). Disability was correlated with subjective tinnitus severity (p=0.0001), panic disorder (p=0.0007), generalized anxiety disorder (p=0.033), and poor sleep quality (p=0.005). Conclusions Our results emphasize the importance of emotional disorders as well as sleep disorders in chronic “tinnitus”. These disorders should be systematically investigated and eventually treated in order to optimize the management of the patients. Disclosure No significant relationships.

Abstract Primary retroperitoneal cavernous hemangioma is an extremely rare disease in clinical practice. It is classified as a vascular tumor. Only three cases have been reported in the literature. The diagnosis is uncommon due to the lack of specific radiological features. It becomes symptomatic as a consequence of its enormous size or complications like rupture or compression. We herein report a unique case of primary retroperitoneal cavernous hemangioma treated with conventional surgery in a 35‐year‐old male patient admitted to our department for chronic abdominal pain. Retroperitoneal cavernous hemangioma is an extremely rare vascular tumor in adulthood. Confirmation is made by histopathological examination after total surgical resection.

Abstract Background Gastric and colorectal cancers are the most common malignant tumours, leading to a significant number of cancer-related deaths worldwide. Recently, increasing evidence has demonstrated that cancer cells exhibit a differential expression of potassium channels and this can contribute to cancer progression. However, their expression and localisation at the somatic level remains uncertain. In this study, we have investigated the expression levels of KCNB1 and KCNA5 genes encoding ubiquitous Kv2.1 and Kv1.5 potassium channels in gastric and colorectal tumours. Methods Gastric and colorectal tumoral and peritumoral tissues were collected to evaluate the expression of KCNB1 and KCNA5 mRNA by quantitative PCR. Moreover, the immunohistochemical staining profile of Kv2.1 and Kv1.5 was assessed on 40 Formalin-Fixed and Paraffin-Embedded (FFPE) gastric carcinoma tissues. Differences in gene expression between tumoral and peritumoral tissues were compared statistically with the Mann-Whitney U test. The association between the clinicopathological features of the GC patients and the expression of both Kv proteins was investigated with χ2 and Fisher’s exact tests. Results The mRNA fold expression of KCNB1 and KCNA5 genes showed a lower mean in the tumoral tissues (0.06 ± 0.17, 0.006 ± 0.009) compared to peritumoral tissues (0.08 ± 0.16, 0.16 ± 0.48, respectively) without reaching the significance rate (p = 0.861, p = 0.152, respectively). Interestingly, Kv2.1 and Kv1.5 immunostaining was detectable and characterised by a large distribution in peritumoral and tumoral epithelial cells. More interestingly, inflammatory cells were also stained. Surprisingly, Kv2.1 and Kv1.5 staining was undoubtedly and predominantly detected in the cytoplasm compartment of tumour cells. Indeed, the expression of Kv2.1 in tumour cells revealed a significant association with the early gastric cancer clinical stage (p = 0.026). Conclusion The data highlight, for the first time, the potential role of Kv1.5 and Kv2.1 in gastrointestinal-related cancers and suggests they may be promising prognostic markers for these tumours.

Abstract This report highlights the case of cystic adventitial disease of the left popliteal artery in a 45‐year‐old male patient. Imaging modalities confirmed the diagnosis and high resolution MRI found a cystic connection to the adjacent knee joint. The evolution was unusual with spontaneous regression of the symptoms.

Abstract Idiopathic sclerosing encapsulating peritonitis is a clinical entity characterized by partial or complete encasement of the digestive tract by a fibrous membrane. The preoperative diagnosis is difficult to establish. The diagnosis of sclerosing encapsulating peritonitis should be considered for patients without any surgical history and admitted for intestinal obstruction, especially for patients having peritoneal dialysis. We herein report the case of a 50‐year‐old man with idiopathic encapsulating peritonitis complicated by intestinal obstruction and ischemia. Idiopathic sclerosing encapsulating peritonitis is a rare disease. The diagnosis is made generally during a surgical procedure. Surgery seems to be the best management option for patients with severe signs of intestinal obstruction. Total resection of membrane avoids recurrences but it is associated with higher morbidity and mortality

Hydatid disease is a cosmopolitan anthropozoonosiss, common to both humans and mammals, is caused by infection with the larval stage of Echinococcus granulosus. It occurs worldwide and is especially common in endemic countries. Hydatid cysts are most commonly found in the liver and lungs.Primary hydatid cysts are rarely detected in muscle tissue, even in endemic countries, it represents less than 1% of all locations of cystic echinococcosis. Clinical signs are often non-specific early on and there are no pathognomonic radiologic features, thus making it difficult to diagnose.Hydatid disease is still considered a major public health issue and must be suspected in front of any cystic musclar mass.We report an unusual case of isolated hydatid cyst in pectoralis muscle without pulmonary or pleural involvement, in a 14-year-old patient, whose pre-operative imagery suggested a cystic lymphangioma and the diagnosis of musclar hydatid cyst was made intra-operatively and confirmed by an anatomopathological examination.

This article is concerned with the adaptive-event-triggered filtering problem as it relates to a class of nonlinear discrete-time systems characterized by interval Type-2 fuzzy models. The system under investigation is susceptible to Markovian switching and deception attacks. It is proposed to implement an improved event-triggering mechanism to reduce the unnecessary signal transmissions on the communication channel and formulate the extended dissipativity specification to quantify the transient dynamics of filtering errors. By resorting to the linear matrix inequality approach and using the information on upper and lower membership functions, stochastic analysis establishes sufficient conditions for the existence of the desired filter, ensuring the mean-squared stability and extended dissipativity of the augmented filtering system. Further, an optimization-based algorithm (PSO) is proposed for computing filter gains at an optimal level of performance. The developed scheme was finally tested through experimental numerical illustrations based on a single-link robot arm and a lower limbs system.

With the increasing demand for electrical energy and the challenges related to its production, along with the need to be environmentally friendly to achieve sustainability for future generations, proton exchange membrane fuel cells (PEMFCs) are emerging as a clean energy source that can effectively replace conventional energy sources, in various fields of application and especially in the field of transportation exploiting electric vehicles (EVs). To improve the development and control of the PEMFCs, the precise determination of its mathematical model remains an essential task. Indeed, the accuracy of such a model depends on the ability to overcome the constraints associated with the nonlinearity and the numerous involved unknown parameters. The present paper proposes a new Dandelion Optimizer (DO) to accurately identify, for the first time, the parameters of the PEMFC model. The DO addresses the weaknesses of the majority of metaheuristic algorithms related to the self-adaptation of parameters, the stagnation of convergence to local minima, and the ability to refer to the whole population. The high ability of the proposed method is investigated using both steady-state and dynamic situations. The DO-based parameters estimation approach has been assessed through a specific comparative study with the most recently published techniques including GWO, GBO, HHO, IAEO, VSDE, and ABCDESC is performed using two typical PEMFC modules, namely 250 W PEMFC and NedStack PS6. The results obtained proved that the proposed approach obtained promising achievements and better performances comparatively with well-recognized and competitive methods.