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Abstract Although the dRGT massive gravity successfully explains the late-time cosmic acceleration, it cannot justify inflation. On the other hand, and in the frameworks of General Relativity and modified gravity, the interests and attempts to describe dark energy and inflation by using Lagranginas, which may have pole, have recently been enhanced. Subsequently, we are going to show that this kind of Lagrangian may justify inflation in the framework of dRGT massive gravity. The study is done focusing on the power and exponential potentials, and the results show a plausible consistency with the Planck 2018 data and its combination with BK18 and BAO.

Abstract In this paper, we study an extended phase space thermodynamics of a nonlinearly charged AdS black hole. We examine both the local and global stabilities, and possible phase transition of the black hole solutions. Finally, we compute quasi-normal modes via scalar perturbations and compare the obtained results with those of Reissner-Nordström black hole.

In this paper, we investigate thermodynamical structure of dyonic black holes in the presence of gravity's rainbow. We confirm that for super magnetized and highly pressurized scenarios, the number of black holes' phases is reduced to a single phase. In addition, due to specific coupling of rainbow functions, it is possible to track the effects of temporal and spatial parts of our setup on thermodynamical quantities/behaviors including equilibrium point, existence of multiple phases, possible phase transitions and conditions for having a uniform stable structure.

Background: The growing gap between organ supply and demand remains a worldwide serious problem.Losing dead-brain donor organs can be attributed to several reasons including un-recognition of potentialdonor by ICU staff, death before official declaration of brain death and high refusal rate of deceaseddonors’ families.Objective: To study the trend of dead-brain patients’ relatives refusal of organ donation from 2007 to 2011.Methods: This study was a retrospective review of all patients who had been introduced as brain death tothe organ procurement unit (OPU) of Iranian Tissue Bank between April 2007 and April 2012 accordingto preliminary neurological exam performed in the hospital of origin. The refusal rate of dead-brainpatients’ families and its reasons was evaluated.Results: A total of 874 ICU admitted patients with severe brain injury (Glasgow coma score

The stepwise Sine-Gordon equation in which the value of the system parameter is different for negative and positive value of the scalar field is investigated. By applying appropriate junction conditions, the relation between solition velocities before and after collision is derived. It turns out that a heavy soliton anti-soliton pair can transform into a light pair moving at right velocities. We call this phenomenon “soliton gun”. Some of the result which were obtained before numerically, are derived analytically in this paper.

There are several observational evidences for the existence of dark matter in the universe. More than about 90% of the matter in the universe is in a form which is not directly observable. If the dark matter is in the form of weakly interacting massive particles (WIMPs) or cosmions, part of it is captured by the Sun, other stars, and even planets. In this paper, some basic ideas of the cosmion hypothesis are presented and the abundance and the coefficient of thermal energy transport by WIMPs are calculated, using an approximate method.

Considering the cosmic fluid as a quasi-static thermodynamic system, the status of the generalized second law of thermodynamics is investigated and the valid range of the equation of state parameter is derived for a few important cosmological models. Our study shows that the satisfaction of the laws of thermodynamics in these cosmological models requires the existence of some kind of energy in our universe with ω

UBV ligh curves together with color curves of the semi-detached eclipsing binary RZ Cas are presented. The light curves are analyzed and the spectroscopic elements and the Hipparcos information are used to compute the absolute parameters of the system. The light curve anomalies and occasional flat minima are discussed. Based on the existing evidence, a straightforward explanation for the primary minimum anomalies is presented.

Background: Gastric cancer (GC) is a highly chemoresistant malignancy with a poor prognosis. Paclitaxel's low response rate as second-line chemotherapy for advanced GC has prompted intensive research into its molecular basis and prospective targeted therapies to enhance its therapeutic efficacy. The objective of this study was to investigate the synergistic effects of NRF2 silencing in combination with paclitaxel treatment on GC cell viability, apoptosis, proliferation, autophagy, and migration., Methods: \After the siRNA-mediated silencing of NRF2 in AGS cells, the transfection efficacy was evaluated by qRT-PCR. The MTT assay was then applied to assess cell viability, followed by flow cytometry analysis for apoptosis, proliferation, and autophagy in AGS cells treated with NRF2 siRNA, paclitaxel, or their combination. Thereafter, the migration of cells was measured using a wound-healing assay. Ultimately, the relative gene expression levels of apoptotic (Bax, Caspase-3, and Caspase-9), anti-apoptotic (Bcl-2), metastatic (MMP-2), and cell cycle (P53) genes were measured by qRT-PCR in all experiment groups to further assess the molecular basis for the combination therapy., Results: NRF2 siRNA transfection significantly enhanced paclitaxel-induced apoptosis and sensitized AGS cells to paclitaxel via modulating the expression of apoptosis-related genes including Bcl-2, Bax, Caspase-3, and Caspase-9. Besides, NRF2 siRNA and paclitaxel synergistically induced cell cycle arrest at the G2 phase, promoted autophagy activation, and inhibited AGS cell migration via MMP-2 downregulation. Additionally, P53, a key regulator of cell growth, was significantly upregulated in the treated groups compared to the control group., Conclusions: Our findings suggest that paclitaxel combined with siRNA-mediated silencing of NRF2 might represent a promising therapeutic strategy for GC, however further translational and clinical research are warranted., (© 2024. The Author(s).)

Pancreatic cancer is one of the most deadly diseases, with a very high metastasis and low survival rate. High levels of NRF2 have been detected in numerous malignancies, including head, neck, lung, and colon cancers, promoting the expansion and survival of cancer cells and chemical resistance to stressful conditions and affecting the response to treatment. To evaluate the possibility that modulation of NRF2 expression could be effective in treating pancreatic cancer cells, we explored the effect of knockdown of the NRF2 gene by NRF2-specific siRNA and its influence in combination with paclitaxel on pancreatic cancer cells. Miapaca-2 cell line, due to the high expression of the NRF2 gene, was selected for this study. Then, Miapaca-2 cells in different groups were treated with NRF2 siRNA and paclitaxel separately and in combination. After that, cell viability was measured by MTT assay and apoptosis induction by Annexin V-FITC/PI staining test. Cell cycle and autophagy were examined by flow cytometry, and cell migration was assessed by wound-healing assay. Finally, the expression of genes involved in apoptosis, Bax, Caspase-3, Caspase-9, and genes related to migration pathway, MMP-2, and MMP-9 in different groups were measured using qRT-PCR. Combined use of NRF2-specific siRNA with paclitaxel significantly reduced NRF2 gene expression in pancreatic cancer cells. NRF2 siRNA transfection significantly reduced cell viability. In addition, paclitaxel combination therapy with NRF2 siRNA strengthens the anti-tumor effects, such as inhibiting cell migration and provoking apoptosis, and autophagy and the cell cycle arrest in the G2 phase. NRF2 suppression augmented the expression of Bax, Caspase-3, and Caspase-9 genes and lowered the expression of Bcl-2, MMP-2, and MMP-9 genes, which play crucial roles in the pathways of apoptosis and cell migration, respectively. NRF2 siRNA enhances the susceptibility of Miapaca-2 cells to paclitaxel in pancreatic cancer cells. Thereby, suppressing NRF2 in combination with paclitaxel can be a new and efficacious treatment approach in treating pancreatic cancer., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Children from families speaking a non-official language at home may be particularly at risk for low physical activity (PA), underscoring a need to investigate correlates of PA in this subpopulation., Methods: We recruited 478 children in 37 schools stratified by area-level socioeconomic status (SES) and type of urbanization within three regions of Canada. Steps/day were measured using SC-StepRx pedometers. We assessed potential social-ecological correlates with child and parent surveys. We used gender-stratified linear mixed models to examine the correlates of steps/day., Results: Outdoor time was the strongest correlate of boys' and girls' PA. Lower area-level SES was associated with less PA among boys, but outdoor time attenuated this difference. The strength of association between outdoor time and PA decreased with age in boys and increased with age in girls., Discussion: Outdoor time was the most consistent correlate of PA. Future interventions should promote outdoor time and address socioeconomic disparities., (© 2023. W. Montague Cobb-NMA Health Institute.)

Background: Youth voice has been largely absent from deliberations regarding public health measures intended to prevent SARS-CoV-2 transmission, despite being one of the populations most impacted by school-based policies. To inform public health strategies and messages, we examined the level of student support of mask use in public spaces and school mask requirements, as well as factors associated with students' perspectives., Methods: We used cross-sectional survey data from 42,767 adolescents attending 133 Canadian secondary schools that participated in the COMPASS study during the 2020/2021 school year. Multinomial regression models assessed support for i) wearing a mask in indoor public spaces and ii) schools requiring students to wear masks, in association with COVID-19 knowledge, concerns, and perceived risk., Results: Wearing masks in indoor public spaces was supported by 81.9% of students; 8.7% were unsupportive and 9.4% were neutral/undecided. School mask requirements were supported by 67.8%, with 23.1% neutral and 9.1% unsupportive. More females supported mask wearing in public spaces (83.9% vs. 79.1%) and school mask requirements (70.8% vs. 63.5%) than males. Students had increased odds of supporting mask use in public spaces and school mask requirements if they reported concerns about their own or their family's health, had discussions regarding ways to prevent infection, perceived COVID-19 to be a risk to young people, and knew that signs are not always present in COVID-19 cases and that masks prevent SARS-CoV-2 transmission if someone coughs., Conclusions: During the year following the beginning of the pandemic, most students supported the required use of masks in schools and wearing masks in indoor public spaces. Improving knowledge around the effectiveness of masks appears likely to have the largest impact on mask support in adolescent populations among the factors studied., (© 2022. The Author(s).)

Purpose: The objective of this scoping review was to summarize systematically the available literature investigating the relationships between the coronavirus disease 2019 (COVID-19) pandemic and movement behaviors (physical activity, sedentary behavior, and sleep) of school-aged children (aged 5-11 years) and youth (aged 12-17 years) in the first year of the COVID-19 outbreak., Methods: Searches for published literature were conducted across 6 databases on 2 separate search dates (November 25, 2020, and January 27, 2021). Results were screened and extracted by 2 reviewers (DCP and KR) independently, using Covidence. Basic numeric analysis and content analysis were undertaken to present thematically the findings of included studies according to the associated impact on each movement behavior., Results: A total of 1486 records were extracted from database searches; of those, 150 met inclusion criteria and were included for analysis. Of 150 articles, 110 were empirical studies examining physical activity (n = 77), sedentary behavior/screen time (n = 58), and sleep (n = 55). Results consistently reported declines in physical-activity time, increases in screen time and total sedentary behavior, shifts to later bed and wake times, and increases in sleep duration. The reported impacts on movement behaviors were greater for youth than for children., Conclusion: The COVID-19 pandemic is related to changes in the quantity and nature of physical activity, sedentary behavior, and sleep among children and youth. There is an urgent need for policy makers, practitioners, and researchers to develop solutions for attenuating adverse changes in physical activity and screen time among children and youth., (Copyright © 2021. Production and hosting by Elsevier B.V.)

Purpose: Biochemical failure after radical prostatectomy has been defined based on retrospective studies in men who underwent RP for localized prostate cancer. Nevertheless, retrospective strategy and possibility of extra-prostatic extension overshadowed the accurateness of the aforementioned cut-off value. To define a more precise PSA nadir value, we estimated serum PSA after cystoprostatectomy in cases with bladder urothelial cancer and no evidence of prostate cancer., Materials and Methods: Study population consists of 52 subsequent patients who underwent radical cystoprostatectomy for muscle-invasive bladder cancer between December 2010 and December 2013. Patients with prostate adenocarcinoma and/or high grade prostate intraepithelial neoplasia were excluded from enrollment. Other exclusion criteria were prostate involvement with urothelial carcinoma, neoadjuvant or adjuvant chemotherapy and radiation therapy. Between all cases, 41 were enrolled for study. Serum PSA level was measured using immunochemiluminescence method among 6 months to 3 years after operation in study participants., Results: Forty-one patients with mean age of 66.4 ± 8.9 were assessed in this study. Average serum PSA level after radical cysto-prostatectomy was .037 ± .031 ng/mL (from .002 to .1). Serum PSA level was not impressed with type of diversion or interval between operation and PSA measurement. Average serum PSA level in this study was meaningfully lesser than .2 ng/mL which is contemplated as PSA nadir value after RP., Conclusion: Serum PSA level of 0.2 ng/mL as the definition for biochemical recurrence after RP may delay salvage treatment. Our results showed that cut off value of ?0.1 ng/mL may be more precise in the era of early salvage treatment.

Purpose: To inform future physical activity (PA) interventions among children, we investigated the correlates of PA among 8- to 12-yr-olds in three regions of Canada: Ottawa, Trois-Rivières, and Vancouver., Methods: We recruited 1699 children (55.0% girls) in 37 schools located in urban, suburban, and rural areas that differed in socioeconomic status. Children wore a sealed SC-StepRx pedometer capable of measuring moderate- to vigorous-intensity physical activity (MVPA) for seven consecutive days. Children and one of their parents/guardians completed a questionnaire that captured multiple potential PA correlates. Publicly available data on weather and neighborhood walkability were obtained. Multiply-imputed gender-stratified linear mixed models were used to examine the correlates of daily step counts and MVPA while controlling for age, site, type of urbanization, and area-level socioeconomic status., Results: Each additional hour spent outdoors was associated with higher PA in boys (+769 steps per day; +3.7 min MVPA per day) and girls (+596 steps per day; +3.5 min·d). Boys' PA declined with age (-500 steps per day; -3.7 min·d). Boys were less active if they had a long-standing injury/illness (-1862 steps per day; -3.7 min·d) or their parents reported driving to work (-835 steps per day; -4.4 min·d), were worried about traffic (-982 steps per day; -6.4 min·d), or about other people in their neighborhood (-1250 steps per day). Girls speaking neither English nor French at home were less active (-620 steps per day; -3.7 min·d). In girls, each degree Celsius increase in morning temperature was associated with 77 additional steps per day, and each kilometer increase in active school travel distance was associated with 0.5 more MVPA minutes per day., Conclusion: Consistent with previous studies, our results suggest that PA interventions should aim to increase outdoor time. The observed gender differences in PA correlates suggest the need for a gender-sensitized approach to PA promotion.

Background: It is important to engage stakeholders and end users in the development of guidelines for knowledge translation purposes. The aim of this study was to examine stakeholders' (experts in pediatric and family medicine, physical activity knowledge translation, and research) and end users' (parents and early childhood educators) perceptions of the Canadian 24-Hour Movement Guidelines for the Early Years (0-4 years)., Methods: Stakeholders (n = 10) engaged in telephone interviews and end users (n = 92) participated in focus groups (n = 14) to discuss perceived clarity and need for the guidelines, potential barriers to implementation, identification of credible messengers, and methods for dissemination of the guidelines. A thematic analysis was conducted., Results: The proposed guidelines were very well received by both stakeholders and end users. A clear need for such guidelines was identified, and most believed the guidelines were achievable. Stakeholders and end users identified several potential barriers to uptake, including low awareness of current guidelines; 'daily challenges' such as allure of screen time, lack of time, and competing priorities; and challenges in the context of shifting social norms. A range of methods and messengers of dissemination were identified. Medical and child care settings were the most frequently cited places for dissemination, and physicians and early childhood educators were the most common suggestions for messengers., Conclusions: There was consistent support for the Canadian 24-Hour Movement Guidelines for the Early Years (0-4 years) from both stakeholders and end users. Moving forward, it is important to dedicate appropriate support and funding toward dissemination efforts in order to reach end users, particularly parents and early childhood educators.

Engaging stakeholders in the development of guidelines and plans for implementation is vital. The purpose of this study was to examine stakeholders' (parents, teachers, exercise professionals, paediatricians, and youth) perceptions of the Canadian 24-Hour Movement Behaviour Guidelines for Children and Youth ("Movement Guidelines"). Stakeholders (n = 104) engaged in semi-structured focus groups or interviews to discuss the perceived acceptability of the guidelines, potential barriers to implementation, and preferred methods and messengers of dissemination. A thematic analysis was conducted. Overall, there was consistent support across all stakeholder groups, with the exception of youth participants, for the Movement Guidelines. Stakeholders identified a range of barriers to the uptake of the guidelines including concerns with accurately defining key terms such as "recreational" screen time; everyday challenges such as financial and time constraints; and the possibility of the Movement Guidelines becoming just another source of stress and guilt for already busy and overwhelmed parents. Participants identified a range of recommended methods and messengers for future dissemination. School and medical settings were the most commonly recommended settings through which dissemination efforts should be delivered. Overall, participants representing a range of stakeholder groups were receptive to the new Movement Guidelines and endorsed their value. In complementing the Movement Guidelines, messaging and resources will need to be developed that address common concerns participants had regarding their dissemination and implementation.

Background: The growing gap between organ supply and demand remains a worldwide serious problem. Losing dead-brain donor organs can be attributed to several reasons including un-recognition of potential donor by ICU staff, death before official declaration of brain death and high refusal rate of deceased donors' families., Objective: To study the trend of dead-brain patients' relatives refusal of organ donation from 2007 to 2011., Methods: This study was a retrospective review of all patients who had been introduced as brain death to the organ procurement unit (OPU) of Iranian Tissue Bank between April 2007 and April 2012 according to preliminary neurological exam performed in the hospital of origin. The refusal rate of dead-brain patients' families and its reasons was evaluated., Results: A total of 874 ICU admitted patients with severe brain injury (Glasgow coma score <7) was introduced to our center and were visited by the coordinator team during April 2007 to April 2012. 412 (47%) patients were excluded from the study mainly due to unsuitability for donation according to the approved medical protocols (n=205) and not fulfilling the brain death criteria (n=66). The families of the remaining cases (n=462) had been interviewed 343 (74.2%) of whom permitted donation. The mean±SD age of donors was 29.8±13.2 years; the male/female ratio was almost 2. The most common reason of brain death was traffic collision (n=120; 56.3%) and cerebrovascular accidents (n=40; 18.8%). The refusal rate from 2007 to 2011 has decreased respectively, from 30.4% to 20% in Tehran, and from 57.1% to 51.6% in other cities. The overall refusal rate was 25.8%., Conclusion: Our study confirmed that more level of expertise of the coordinator team and continuous public education, would result in higher rate of consent to organ donation.