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Abstract This retrospective study aimed to assess different macular neovascular network characteristics in relation to changes in best corrected visual acuity (BCVA) over 3 and 12 months following treatment. Using optical coherence tomography angiography, we reviewed the medical records of 46 treatment-naïve patients with neovascular age-related macular degeneration (nAMD) who received intravitreal aflibercept injections. The change in BCVA from baseline to 3 months and 12 months after treatment was recorded. The mean vessels percentage area, junctions density, lacunarity, and fractal dimension were significantly correlated with the change of BCVA from baseline to month 3 (P = 0.003, 0.046, 0.007, and 0.005 respectively). Fractal dimension and vessels percentage area were correlated with the change of BCVA from baseline to month 12 (P = 0.023 and 0.023 respectively). The findings suggest that baseline characteristics of macular neovascular complexes may serve as predictors for BCVA changes following treatment with aflibercept in nAMD patients.

In this study, blends of silicone rubber (SR) and benzoxazine (BZ) were prepared accompanied by ethylene propylene diene monomer grafted with maleic anhydride (EPDM-g-MA) as the compatibilizing agent. A total of 3 phr MA grafted EPDM showed the most favorable grafting efficiency and relatively lower gel content. Results showed that 8 phr (EPDM-g-MA) was the optimal compatibilizer content in the 85/15 SR/BZ blend, which was used for further studies. Morphological studies proved that the greatest reduction in the dispersed droplet size (from 1.32 to 0.23 [micro]m) occurred at this optimal compatibilizer loading (8 phr). The lowest difference between the glass transition temperatures of the blend components was observed at the 8 phr compatibilizer content, which was confirmed by DMTA. The mechanical and curing characteristics of compatibilized and uncompatibilized blends were also studied. The results evinced that the tensile strength of the compatibilized samples was higher than that of the uncompatibilized blends. Thermal studies on the 85/15 SR/BZ blend and nanocomposites containing 1, 3, and 5 phr polyhedral oligomeric silsesquioxane (POSS) nanoparticles revealed that the thermal stability of nanocomposites containing 1 and 3 phr POSS was superior to that of the nanocomposite with 5 phr POSS. KEYWORDS benzoxazine, compatibilization, elastomer, nanocomposite, phenolic resin, 1 | INTRODUCTION The application of elastomeric modified phenolic resins for thermal protection systems (TPS) has been widespread in recent years. TPSs are materials known for their stability and high [...]

Abstract Purpose The problem of image denoising in single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a fundamental challenge. Although various image processing techniques have been presented, they may degrade the contrast of denoised images. The proposed idea in this study is to use a deep neural network as the denoising procedure during the iterative reconstruction process rather than the post-reconstruction phase. This method could decrease the background coefficient of variation (COV_bkg) of the final reconstructed image, which represents the amount of random noise, while improving the contrast-to-noise ratio (CNR). Methods In this study, a generative adversarial network is used, where its generator is trained by a two-phase approach. In the first phase, the network is trained by a confined image region around the heart in transverse view. The second phase improves the network’s generalization by tuning the network weights with the full image size as the input. The network was trained and tested by a dataset of 247 patients who underwent two immediate serially high- and low-noise SPECT-MPI. Results Quantitative results show that compared to post-reconstruction low pass filtering and post-reconstruction deep denoising methods, our proposed method can decline the COV_bkg of the images by up to 10.28% and 12.52% and enhance the CNR by up to 54.54% and 45.82%, respectively. Conclusion The iterative deep denoising method outperforms 2D low-pass Gaussian filtering with an 8.4-mm FWHM and post-reconstruction deep denoising approaches.

Introduction: It has been demonstrated that an increase in the diameter of the right ventricle or pulmonary artery in COVID-19 patients could be associated with the severity of lung involvement and may lead to unfavorable outcomes, particularly in the presence of pulmonary vascular diseases. This study investigated the relationship between these right heart strain features, the extent of lung involvement, and their prognostic values in patients without vascular comorbidities. Methods: This study selected 154 consecutive patients with positive chest computed tomography (CT) findings and no evidence of concurrent pulmonary disease. Clinical characteristics and adverse outcomes in in-hospital settings were collected retrospectively. Diameters of cardiac ventricles and arteries, along with lung opacification scores, were obtained using CT pulmonary angiography (CTPA) findings, and the association of these variables was evaluated. Results: An increase in pulmonary artery (PA) to ascending aorta (AO) diameter ratio and lung parenchymal damage were significantly and positively correlated (P=0.017), but increased right ventricle (RV) to left ventricle (LV) diameter ratio showed no association with the extent of chest opacification (P=0.098). Evaluating the prognostic ability of both ratios using logistic regression and receiver operating characteristic (ROC) analysis proved no significant class separation in regards to predicting adverse outcomes (PA/AO: OR:1.081, P Value:0.638, RV/LV: OR:1.098, P Value:0.344). Conclusion: In COVID-19 patients without vascular comorbidities, a higher PA/AO diameter ratio was significantly associated with increased lung involvement severity on CT imaging but not with adverse in-hospital outcomes. Conversely, an increased RV/LV ratio on CTPA did not correlate significantly with adverse outcomes or the severity of parenchymal lung damage.

Background and objectives: Bicycle-sharing is a relatively new idea, but concerns about its popularity, benefits, and potential harms behind it have sparked heated debate in the public and academic circles. However, there is still a gap between describing the phenomenon and evaluating its effectiveness. Therefore, a correct understanding of the decision-making processes in the adoption and use of shared bicycle systems can enable operators to plan their services in a more optimal way. The bicycle distribution system, if planned well, can play a complementary role in the existing transportation infrastructure. Due to the recent growth of bicycle sharing systems in large countries such as China, Europe, and the United States, there is a great interest in identifying factors influencing this system to encourage people using it. Therefore, one of the most important challenges in this field is the factors affecting the level of user satisfaction, and better identification and understanding of these factors can help improve the user experience and increase the use of this system. So far, many researches have been conducted on the components affecting the functional stability of the shared bicycles system, for example Si et al. in 2020 found that factors of efficiency, economic benefits, environmental awareness, and infrastructure incentives influence the willingness to use the shared bicycle system. Also, other studies in this field have found factors such as mental norms, behavioural norms, appearance quality, ease of use, flexibility, and safety to be effective on the willingness to use the shared bicycle system (X. Li et al., 2022; Shao et al., 2020; Zhou & Zhang; 2018). But this issue has not been fully investigated yet. Dockless Bicycle Sharing system (DBSS) with different brand names such as: Mobicycle, Ofo, Youbicycle, etc., and recently with Bidood brand, have been expanded in Iran. Therefore, according to the issues and needs raised, as well as the few studies that have been conducted in the field of investigating the efficiency and use of shared bicycles in Iran, especially in the metropolis of Tehran, the current research seeks to identify the factors affecting the use of the bicycle sharing system in Tehran in the field of urban planning and policy making, to provide guidance for city managers and operators of the shared bicycle system.Methods: In the current research, structural equation modelling (SEM) has been used to analyse latent variables, their relationships and test hypotheses according to the conceptual model of the research. It used the simple random sampling method and the required data was collected through a questionnaire, the items of which were mainly obtained from the review of the literature related to shared bicycles, its mechanism, and the presented conceptual model. A questionnaire was distributed both face-to-face and non-face-to-face (through virtual platforms such as Eitaa etc.). To check the validity and reliability of the measurement tool, improve the questions, format and scales, a pilot study of potential participants was conducted. Finally, 270 questionnaires were collected, and after screening the data, 248 questionnaires were approved. Descriptive analysis of collected data was done through SPSS version 26.0, such as data screening, frequencies, percentages and reliability analysis, and AMOS version 26.0 software was used for modelling, model analysis and hypothesis testing.Results and conclusion: Based on findings, the five components defined in the conceptual model, including quality and performance, distribution and parking, comfort and flexibility, safety and environment, and the usefulness of services, affect the satisfaction and use of users of the shared bicycle system. The results of the squared multiple correlations, which express the degree of explanation of the data variance by the model, showed that the five variables in question constitute 64% of the variance of the satisfaction variable (R2 = 0.64), with comfort and flexibility having the greatest impact on the satisfaction and use of the shared bicycle system. After that, quality and performance, service desirability, safety and environment, and distribution and parking have the most impact respectively. The findings indicate that the better the quality and performance, the conditions of distribution and parking, and the comfort and flexibility of the shared bicycle system, the greater the satisfaction and the amount of usage. In the same way, the more the shared bicycle system has higher safety and provides better services to users (have more safety and desirability), the more satisfaction and the amount of usage will be. The findings from the descriptive statistics showed that the quality and performance of bicycle sharing in terms of lightness and easy portability of bodies, beautiful design and lock function, the condition of distribution and parking of shared bicycles, the ease of access and parking, the number of bicycles, the method of deployment and management, the comfort and flexibility of bicycle sharing in terms of ease of movement in traffic, the freedom of action in choosing the route and ease of access to public transportation, and the safety of bicycles and cycling paths are not at acceptable levels. On the other hand the bicycle sharing system was considered acceptable by respondents in terms of environmental (low pollution and reduction of carbon consumption). The service quality of the bicycle sharing system was found not at a suitable level in terms of rental cost, reasonable deposit, application performance and QR sensitivity. In terms of the compatibility of the application (APP) with the mobile operating system and the ease of the registration process, however they were found at a relatively favourable level. The findings of the descriptive statistics from the satisfaction variable showed that the overall satisfaction of the users (tendency to reuse and recommend this system to others) is at a very low level, but if the services is improved, they will accept this green transportation system.The purpose of this study is to identify the factors affecting the use of shared bicycle systems in Tehran metropolis, to provide guidance for city managers and relevant operators in the field of planning, decision-making and policy making. The results of this research showed that 5 components: quality and performance, distribution and parking, comfort and flexibility, safety and environment, and the desirability of service influence the satisfaction and use of the shared bicycle system. Therefore, it is necessary for managers and urban planners and policymakers to take measures to improve the performance level of the five components proposed in this research, including the integration of shared bicycle system with public transportation, better management of distribution and parking of bicycles, increase safety of bicycles and improvement of servic

Purpose: To assess subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) profile in the Iranian healthy population and assessment of the inter-eye difference in this regard. Methods: In a cross-sectional study, 141 healthy subjects underwent an assessment of refraction and best-corrected visual acuity (BCVA), axial length (AL), and measurement of the intraocular pressure. The imaging of the choroid was performed using the enhanced-depth imaging mode of Spectralis optical coherence tomography from the foveal slab to measure SFCT and calculate CVI. Results: A total of 282 eyes of 141 healthy subjects (59.6% men, mean age of 60.86 ± 11.46 years) enrolled in the current study. The mean SFCT of the right and left eye was 247.40 ± 70.37 and 251.25 ± 72.19, respectively. The mean CVI of the right and left eye was 62.63 ± 3.77 and 63.19 ± 3.91, respectively. None of the measured parameters had statistically significant differences between the left and right eyes. In both univariate and multivariate regression analysis, CVI was significantly associated with BCVA (P < 0.001) but was not associated with age, spherical equivalent (SE), gender, central macular thickness (CMT), and SFCT. In univariate regression analysis, SFCT was significantly associated with age, refraction (P = 0.02), BCVA (P = 0.003), AL (P < 0.001), and CVI (P = 0.02) but not significantly associated with gender and CMT. In multivariate analysis, age (P < 0.001), gender (P = 0.001), and AL (P < 0.001) were significantly associated with SFCT, but SE, BCVA, CVI, and CMT were not significantly associated. Conclusions: This was the first investigation to assess the SFCT and CVI simultaneously in the Iranian population to establish a normative database for future studies. CVI was less variable than SFCT in a healthy population, and no statistically significant differences existed between the left and right eyes.

Abstract The increasing use of hexavalent chromium (Cr(VI)) has exposed large populations to this environmental and occupational carcinogenic agent. Therefore, researchers have been interested in removing this substance through adsorbents. This study aimed to investigate the efficiency of natural zeolite in the direct adsorption of Cr(VI) from airflow and its adsorption modeling. In this study, a nebulizer device produced the Cr(VI) mist. The efficiency of natural zeolite in Cr(VI) adsorption from airflow, modeling of fixed column adsorption, and the effective parameters on adsorption efficiency including the initial concentration of chromium, airflow rate, and adsorption bed depth were studied. To facilitate the prediction of the performance of natural zeolite’s adsorption column, Yoon–Nelson, Thomas, BDST, and Buhart–Adams models were used. The results showed that the adsorption capacity diminished with increased airflow rate and initial concentration, while it increased with elevated height of the adsorption bed. Yoon–Nelson, Thomas, and BDST models corresponded to experimental data with a correlation coefficient of 0.9933, but the information of the Buhart–Adams model had a lower correlation coefficient (around 0.6677). In conclusion, natural zeolite can be used as an efficient low-cost adsorbent for directly Cr(VI) removing from the airflow in a fixed bed column.

The linguistic symbols present in a particular work can convey a multitude of meanings contingent upon the mystic's spiritual experiences, temporal conditions, status, and life. A primary objective and methodology of semiotics is to investigate this horizon of meaning and reveal the process of creating meaning. Umberto Eco, through his mastery of various methods of semiotic analysis and the unique qualities of each method, has attempted to develop a synthetic and interpretative theory of semiotics. In this article, Ṣafwat al-Ṣafā, written by Ibn Bazzāz, has been chosen as the primary source for the study and research of dream and spiritual phenomena. Ṣafwat al-Ṣafā is a collection of the spiritual experiences of Sheikh Ṣafī al-Dīn Ardabīlī and his mentor, Sheikh Zāhed Gīlānī. This research aims to elucidate the process of producing spiritual phenomenon and its comprehension and interpretation. The research findings indicate that, although spiritual phenomena are typically considered as a message for the spiritual wayfarer (sālik) from the realm of archetypes (ʿālam maʿnā), from the perspective of the theory of "sign creation" and spiritual phenomenon, it is a coin which on one side is the path of communication between the spiritual wayfarer and the world of archetypes, and on the other side is message from the world of the archetypes to the spiritual wayfarer. The spiritual wayfarer is the recipient of this message; however, he is not able to comprehend the meaning of the message. They can only convert the message to linguistic signs. The pīr(spiritual guide) is the interpreter of the spiritual phenomenon, and it is the pīr who reveals the primary message of the phenomenon to the spiritual wayfarer. Furthermore, spiritual phenomena are signs that have different functions, such as the endeavor to "find the Truth" and "educational functions."

Abstract Background The study aimed to evaluate the prevalence and pattern of long COVID-19 (LC) symptoms among individuals who had contracted COVID-19, to calculate the incidence of LC, and to provide insights into risk factors associated with developing LC in this population. Methods This population-based cross-sectional survey was conducted in Fars province in 2023. Adult participants with a history of COVID-19 were recruited using a cluster random sampling method, alongside a control group with similar characteristics through the same methodology. Data were collected through in-person interviews using two researcher-developed data collection forms focused on demographic and clinical information. Results A total of 2010 participants, comprising 1561 (77.7%) and 449 (22.3%) individuals with and without a previous history of COVID-19 were included. Among those with COVID-19 history, the prevalence of experiencing any symptoms was 93.7% (95% CI of 92.3%-94.8%) during the disease acute phase and 36.4% (95% CI of 34.0%-38.8%) after recovery. The incidence of symptoms specifically related to COVID-19, calculated by comparing the symptom rates between participants with and without a history of COVID-19, was found to be 13%. Factors such as older age, previous hospitalization for COVID-19, presence of cardiovascular disease, and use of steroids/chemotherapy were associated with LC symptoms. Conclusions Our investigation sheds light on long-term aspects of COVID-19, demonstrating a significant prevalence of LC with diverse manifestations. It also underscores the importance of establishing standardized criteria and control groups in research on LC to address challenges related to heterogeneity and potential overestimation of symptoms.

Abstract Background This study aims to investigate international measures for pandemic control in the workplace based on guidelines from international organizations to learn from their experiences. Methods We conducted a qualitative study using content analysis. The search method involved reviewing published guidelines on preventing and responding to the COVID-19 pandemic in workplaces. After the screening process, ten guidelines were included in the content analysis. During the analysis, 200 meaning codes, 49 subcategories, and eleven categories were identified. Trustworthiness criteria were utilized to ensure the accuracy and strength of the findings. Results Eleven categories of international content during the COVID-19 pandemic were legal requirements and duties of employees and employers, structural and program changes, risk assessment, risk communication, information and training, internal and external consultation and cooperation, provision of facilities and tools for workplace hygiene, special conditions, special groups, closing and reopening workplaces, reducing contact and exposure and mental health. Conclusions Protecting employees during a pandemic requires a multifaceted approach and strong advocacy. The operational plan for pandemic control should be developed based on the level of risk, with support tailored to employees’ conditions and needs. Cooperation among international organizations is essential to develop a standardized plan and issue comprehensive guidelines in response to health emergencies with a global perspective and local implementation, drawing from the lessons learned during the COVID-19 pandemic.

In this study, we present the design and fabrication of a V-shaped resonator that served as an absorption chamber in a laser spectroscopy system for water stable isotope measurement (2H, 17O, 18O) based on optical feedback cavity-enhanced absorption spectroscopy. In the design of a resonator, its length and the radius of curvature of the mirrors guarantee the optical stability of the system. The resonator mirrors are designed considering the condition of stability and based on the desired mode structure of the resonator output. The V-shaped resonator is designed with two arms of 40 cm and inner diameters of 5 mm making an angle of 1.7°. This resonator has an internal volume of 20 cm3 which provides fast response of laser spectrometer. The high reflectivity of mirrors leads to an effective absorption optical path length of 13 km and a high finesse optical resonator of Ƒ~52،000. These values allow low concentration water vapor isotope analyses and resolution of the absorption spectrum of isotopes for accurate isotope measurements, respectively. Resonator mirrors are designed using Mcleod software to have maximum reflectance at a wavelength of 1.4 micrometers. By making a V-shaped optical resonator for measuring stable isotopes of water and subsequent development for measuring stable isotopes of other elements, the possibility of developing the application of stable isotopes in different areas of research will be provided.

Abstract Background and purpose The workplace plays a key role in impacting the health and well-being of employees at various levels, including physical, psychological, and social aspects of health. This study aims to identify the drivers of a healthy environment that promotes the well-being of women employed in hospitals. Materials & methods This qualitative study used purposive sampling to recruit a total of 48 working women across a diverse range of participants with different job categories and socio-demographic statuses. These include clinical health (e.g., nurse, head nurse, practical nurse, supervisor, physicians); allied health (e.g., diagnostic services); public health (e.g., health promotion specialists); and administrative (e.g., hospital managers). Data was collected through semi-structured interviews and were analyzed using content analysis by creating codes, sub-themes, and themes. Results Content analysis resulted in 31 key codes, that generated 12 sub-themes and 4 key themes. These include Advancing women’s health through collaborative leadership; a Psychologically safe environment for women; Thriving for positive social connections; and Advancing holistic health for women. Discussion and Conclusion Hospital managers and leaders play a pivotal role in creating supportive workplaces for women. They can significantly assist in prioritizing their psychological and social health through personalized approaches tailored to women’s needs, positioning them as co-designers of their health and well-being.