107 research outputs found
On the performance of equiangular mascon solution in GRACE-like missions
No full textMass concentration (mascon) solutions for GRACE (Gravity Recovery and Climate Experiment) data are widely used in various regional-to-global mass change studies. The current advances in the mascon solution have mainly concentrated on improving the spatial resolution of the solution, enhancing the applied least-squares regularization, and the characterization of the solution errors. Most of the mascon solutions are obtained on the equal-area grid, inducing complexities in creating the grid and its presentation. In this regard, estimation of the mascon solutions on equiangular grids can be appealing. Furthermore, in the equal-area methods, there is no global criterion to determine the size of the mascon areas. The mascon size is usually chosen in a subjective manner which hampers the objective application of different mascon solutions. In view of these challenges, two main questions are addressed in this study: i) what kind of modifications should be made in computation scheme of the mascon solution if equiangular grids are used to account for different areas of the grid patches, and ii) in case of non-equiangular solutions, how to define an objective criterion for the patch sizes based on the resolution of both the observation and the signal of interest. We investigate the performance of the high-resolution mascon-based approach, proposed by Abedini et al. [2021], which uses GRACE-like observations similar to level-1 data for a period of one month over the Greenland region. Two main practical issues are studied on the estimation of the surface density changes as follows. First, we show that for equiangular grids, the area of the patches should be accounted for in the regularization by introducing area-affected weights for the unknown parameters. We investigate the effect of three different area-affected weighting strategies on the derived solution. Secondly in order to obtain proper size for the patches, a novel approach is presented to investigate the performance of the mascon solution using the analysis of the resolution matrix entries. The proposed resolution analysis is used to obtain the optimal patch size for the discretization of the area of interest. Based on the results, it is demonstrated that the minimum legible patch size in the Greenland area for the current settings of the GRACE observations is 0.5 degree in the NS direction and a latitude-adaptive grid-size rather than equiangular grids at high latitude regions in the EW direction.Optical and Laser Remote Sensin
Elucidation of the biological roles of Wnt5a signaling in follicle development
Get PDFLa santé folliculaire est déterminée par un nombre de facteurs endocriniens, paracrines et autocrines. Les gonadotrophines hypophysaires sont les principaux moteurs du développement du follicule, mais leurs actions sont modulées localement par les hormones et des facteurs de croissance. Les glycoprotéines de la famille des WNTs représentent une grande famille de molécules impliquées dans différentes voies de signalisation. Ils sont sécrétés dans le but de moduler et coordonner la réponse des follicules aux gonadotrophines, et leurs activités sont indispensables à la fonction ovarienne et à la fertilité féminine. Les WNTs sont généralement classés en fonction de la (des) voie(s) qu’ils activent. Le rôle des membres de la voie canonique WNT et de ses composants tels que CTNNB1, WNT4, WNT2, FZD1 et FZD4 est bien établi au cours du développement du follicule chez les rongeurs. Un rôle similaire des WNTs dans les espèces mono-ovulatoires demeure essentiellement inconnu. De plus, le rôle des WNT non canoniques dans l'ovaire de rongeurs est méconnu. Les objectifs de cette thèse sont (1) d'élucider la régulation hormonale de l'expression de WNT5A et le rôle physiologique de WNT5A dans les cellules de la granulosa bovine in vitro et (2) d'identifier les rôles physiologiques de WNT5A dans l'ovaire de souris par inactivation génique conditionnelle. Chacun de ces objectifs a mené à la publication d’un article à partir des résultats obtenus au cours de cette thèse. Dans le premier article, le rôle de WNT5A dans les cellules de la granulosa bovine a été étudié in vitro. Nous avons constaté que WNT5A est un régulateur négatif de la stéroïdogenèse stimulée par la FSH issue des cellules de la granulosa, et qu'il agit en supprimant l'activité de signalisation des WNTs canoniques tout en induisant la voie de signalisation MAPK8/JUN. le deuxième article, afin d’examiner le rôle de deux WNTs non-canoniques, WNT5A et WNT11, à différents stades de développement folliculaire, nous avons généré des modèles de souris knock-out conditionnels ciblant les cellules de la granulosa pour chacun de ces WNTs. Les résultats obtenus ont permis de mettre en évidence que WNT5A est nécessaire pour assurer la fertilité normale chez la femelle, le développement folliculaire et la stéroïdogenèse ovarienne. Il est aussi un antagoniste de la réponse aux gonadotrophines, agissant par l’intermédiaire de la suppression de la signalisation canonique des WNTs. Chez les souris knock-out pour WNT11, nous ne constatons aucun défaut important dans la fertilité des femelles. L’ensemble de notre travail met en évidence que WNT5A est essentiel pour le développement normal du follicule et qu’il agit pour inhiber la différenciation des cellules de la granulosa. En résumé, nous avons fourni une étude novatrice et approfondie, utilisant plusieurs modèles et techniques pour déterminer les mécanismes par lesquels WNT5A régule le développement des follicules.Follicle health is determined by an array of endocrine, paracrine and autocrine factors. Pituitary gonadotropins (LH and FSH) are major drivers of follicle development, but their actions are modulated by local hormones and growth factors. The WNT family of secreted glycoproteins are signaling molecules that act to modulate and coordinate follicular responses to the gonadotropins, and whose activities are indispensable for ovarian function and female fertility. WNTs are normally categorized according to pathway(s) via which they signal. The role of canonical WNT members and components such as CTNNB1, WNT4, WNT2, FZD4 and FZD1 is well established during follicle development in rodents. Whether WNTs play similar roles in monovular species remains essentially unknown. Moreover, the role of non-canonical WNTs in the rodent ovary is unclear. The objectives of the present thesis were (1) to elucidate the hormonal regulation of WNT5a expression and the physiological role of WNT5a in bovine granulosa cells in vitro and (2) to identify the physiological roles of WNT5a in the mouse ovary by conditional gene inactivation. The results of this thesis are presented in two articles. In the first article, the role of WNT5a in bovine granulosa cells was investigated in vitro. We found that WNT5A is a negative regulator of FSH-stimulated granulosa cell steroidogenesis, and that it acts by suppressing canonical WNT signaling activity and inducing the noncanonical MAPK8/JUN pathway. In the second article, we generated granulosa-specific knockout mouse models to examine the roles of two non-canonical WNTs, WNT5a and WNT11, in different stages of the follicular development. Our results showed that WNT5a is required for normal female fertility, follicle development and ovarian steroidogenesis, and is an antagonist of gonadotropin responsiveness that acts via the suppression of canonical WNT signaling. However we did not observe any significant defects in fertility of WNT11 knockout mice. Together, our work demonstrates that WNT5a is essential for normal follicle development and acts to inhibit differentiation in granulosa cells. In overview, we provided a novel and comprehensive investigation, using multiple models and techniques, to determine the mechanisms by which WNT5a regulates follicle development
Elucidation of the biological roles of Wnt5a signaling in follicle development
Get PDFLa santé folliculaire est déterminée par un nombre de facteurs endocriniens, paracrines et autocrines. Les gonadotrophines hypophysaires sont les principaux moteurs du développement du follicule, mais leurs actions sont modulées localement par les hormones et des facteurs de croissance. Les glycoprotéines de la famille des WNTs représentent une grande famille de molécules impliquées dans différentes voies de signalisation. Ils sont sécrétés dans le but de moduler et coordonner la réponse des follicules aux gonadotrophines, et leurs activités sont indispensables à la fonction ovarienne et à la fertilité féminine. Les WNTs sont généralement classés en fonction de la (des) voie(s) qu’ils activent. Le rôle des membres de la voie canonique WNT et de ses composants tels que CTNNB1, WNT4, WNT2, FZD1 et FZD4 est bien établi au cours du développement du follicule chez les rongeurs. Un rôle similaire des WNTs dans les espèces mono-ovulatoires demeure essentiellement inconnu. De plus, le rôle des WNT non canoniques dans l'ovaire de rongeurs est méconnu. Les objectifs de cette thèse sont (1) d'élucider la régulation hormonale de l'expression de WNT5A et le rôle physiologique de WNT5A dans les cellules de la granulosa bovine in vitro et (2) d'identifier les rôles physiologiques de WNT5A dans l'ovaire de souris par inactivation génique conditionnelle. Chacun de ces objectifs a mené à la publication d’un article à partir des résultats obtenus au cours de cette thèse. Dans le premier article, le rôle de WNT5A dans les cellules de la granulosa bovine a été étudié in vitro. Nous avons constaté que WNT5A est un régulateur négatif de la stéroïdogenèse stimulée par la FSH issue des cellules de la granulosa, et qu'il agit en supprimant l'activité de signalisation des WNTs canoniques tout en induisant la voie de signalisation MAPK8/JUN. le deuxième article, afin d’examiner le rôle de deux WNTs non-canoniques, WNT5A et WNT11, à différents stades de développement folliculaire, nous avons généré des modèles de souris knock-out conditionnels ciblant les cellules de la granulosa pour chacun de ces WNTs. Les résultats obtenus ont permis de mettre en évidence que WNT5A est nécessaire pour assurer la fertilité normale chez la femelle, le développement folliculaire et la stéroïdogenèse ovarienne. Il est aussi un antagoniste de la réponse aux gonadotrophines, agissant par l’intermédiaire de la suppression de la signalisation canonique des WNTs. Chez les souris knock-out pour WNT11, nous ne constatons aucun défaut important dans la fertilité des femelles. L’ensemble de notre travail met en évidence que WNT5A est essentiel pour le développement normal du follicule et qu’il agit pour inhiber la différenciation des cellules de la granulosa. En résumé, nous avons fourni une étude novatrice et approfondie, utilisant plusieurs modèles et techniques pour déterminer les mécanismes par lesquels WNT5A régule le développement des follicules.Follicle health is determined by an array of endocrine, paracrine and autocrine factors. Pituitary gonadotropins (LH and FSH) are major drivers of follicle development, but their actions are modulated by local hormones and growth factors. The WNT family of secreted glycoproteins are signaling molecules that act to modulate and coordinate follicular responses to the gonadotropins, and whose activities are indispensable for ovarian function and female fertility. WNTs are normally categorized according to pathway(s) via which they signal. The role of canonical WNT members and components such as CTNNB1, WNT4, WNT2, FZD4 and FZD1 is well established during follicle development in rodents. Whether WNTs play similar roles in monovular species remains essentially unknown. Moreover, the role of non-canonical WNTs in the rodent ovary is unclear. The objectives of the present thesis were (1) to elucidate the hormonal regulation of WNT5a expression and the physiological role of WNT5a in bovine granulosa cells in vitro and (2) to identify the physiological roles of WNT5a in the mouse ovary by conditional gene inactivation. The results of this thesis are presented in two articles. In the first article, the role of WNT5a in bovine granulosa cells was investigated in vitro. We found that WNT5A is a negative regulator of FSH-stimulated granulosa cell steroidogenesis, and that it acts by suppressing canonical WNT signaling activity and inducing the noncanonical MAPK8/JUN pathway. In the second article, we generated granulosa-specific knockout mouse models to examine the roles of two non-canonical WNTs, WNT5a and WNT11, in different stages of the follicular development. Our results showed that WNT5a is required for normal female fertility, follicle development and ovarian steroidogenesis, and is an antagonist of gonadotropin responsiveness that acts via the suppression of canonical WNT signaling. However we did not observe any significant defects in fertility of WNT11 knockout mice. Together, our work demonstrates that WNT5a is essential for normal follicle development and acts to inhibit differentiation in granulosa cells. In overview, we provided a novel and comprehensive investigation, using multiple models and techniques, to determine the mechanisms by which WNT5a regulates follicle development
Prisoner in the Darkness
Get PDFThis thesis details the writing process and performance of the author’s one man show, PRISONER IN THE DARKNESS. Adapted with special permission from Naghmeh Abedini, PRISONER IN THE DARKNESS is based on the letters, correspondences, and reports of Saeed Abedini, an American citizen, imprisoned in Iran. Pastor Saeed went back to his homeland to work on humanitarian efforts; however, he was wrongfully arrested and sent to Evin Prison in September 2012. In January 2013, Saeed was sentenced to eight years in prison for conspiring to undermine the Iranian government. His crime? His Christian faith. This thesis will explain the different aspects of creating the script, creating the world of the play, and creating the character of Saeed Abedini. The author shares the joys and difficulties of the rehearsal period, reflects on the final performances, and entertains possible script adjustments towards the future development of the play. A written copy of the script is included
Differential diagnosis of tuberculosis, sarcoidosis, and anthracosis by CD8, CD3, and CD4 levels by flow-cytometry
Get PDFBackground: Determination of a desirable diagnostic tests is an issue of importance especially to differentiate between tuberculosis) TB(, sarcoidosis, and anthracosis. The purpose of the present study was to determine the differential diagnosis of tuberculosis, sarcoidosis and anthracosis with CD8, CD3, and CD4 by flow-cytometry. Materials and Methods: In this descriptive cross-sectional comparative survey, 40 consecutive patients attending to Masih Daneshvari Hospital in Tehran were enrolled and CD4/CD8 ratio, CD8, CD3, and CD4 were determined by flow-cytometry and compared across patients with three diseases including tuberculosis, sarcoidosis, and anthracosis.Results: The results demonstrated that CD4 was significantly higher in anthracosis cases (P<0.007) and the CD8 was significantly higher in patients with TB (P<0.008).Conclusion: It was attained ultimately that CD4 and CD8 levels could be a desirable diagnostic markers for anthracosis and TB, respectively
Correction to: A Randomized Clinical Trial of a Modified Mindfulness-Based Cognitive Therapy for Children Hospitalized with Cancer (Mindfulness, (2021), 12, 1, (141-151), 10.1007/s12671-020-01506-3)
Get PDFIn the original published version of this article, Dr. Randye J. Semple was captured as corresponding author instead of Dr. Mojtaba Habibi. Dr. Semple took the role of pre-publication correspondent simply because she is more familiar with the journal�s online submission process than Dr. Habibi. Thus, this erratum is presented to fix the error. The original article has been corrected. © 2020, Springer Science+Business Media, LLC, part of Springer Nature
Evaluation of interleukin 6 (IL-6) and interleukin 8 (IL-8) as prognosis factors in Coronavirus disease (COVID-19)
No full textBackground and Objective: Better understanding of immunopathogenesis and finding the relationship between disease severity and some cytokines, is an introduction to further research on new biological drugs with the specific aim of obtaining these cytokines can be provided. The present study was performed to determine the ratios of IL-6 and IL-8 (IL-6, IL-8) in Iranian patients with COVID-19.
Materials and Methods: One of our goals is to find a relationship between serums levels of hypothetical cytokines involved in the severity of COVID-19 disease by measuring the serum concentrations of these cytokines in COVID-19 patients at baseline as a prognostic factor.
Results: Regarding right lung involvement as well as involvement of both lungs, there was a significant difference between patients with severe and mild disease severity (p-value <0.001). Ferritin levels were significantly higher in the severely ill group than in the mildly ill group (p-value = 0.003). CRP levels were higher than normal in 93.3% of patients in the present study. CRP levels were not associated with disease severity but were effective in predicting the disease. ESR level was higher than normal in 88% of patients and was effective in prognosis the disease. The mean serum level of interleukin-8 in 38 severe patients was significantly higher than the mean serum level of interleukin 8 in 21 mild patients (p-value <0.001). Death was reported in 11 patients (18.6%). Mortality rate and disease severity showed a significant relationship (p-value = 0.006). The disease was significantly more severe in patients with positive PCR (p-value = 0.026).
Conclusions: In several patients, the serum level of interleukin 8 has been a good evaluator of disease prognosis. Symptoms of COVID-19 may be due to elevated levels of interleukin-8 and its receptor. Therefore, it is suggested that in future studies, interleukin 8 receptor mRNA be tested for the discovery of new biological drugs against COVID-19
Serum ACE level in sarcoidosis patients with typical and atypical HRCT manifestation
No full textBACKGROUND: Sarcoidosis is an inflammatory disease that affects multiple organs. Before widespread use of computed tomography (CT), the severity of sarcoidosis was assessed based on chest X-ray abnormalities. HRCT can distinguish between active inflammatory changes and irreversible fibrosis. In this study, we analyzed different ACE levels in 148 patients diagnosed with sarcoidosis. MATERIAL AND METHODS: We categorized these patients based on their HRCT results into four groups: 1) patients diagnosed with chronic disease; 2) patients diagnosed with non-chronic disease; 3) patients who exhibited typical HRCT changes; and 4) patients who exhibited atypical HRCT changes. Afterward the mean ACE level of each group was calculated and compared. RESULTS: The HRCT scans of chronic sarcoidosis patients tended to show more atypical sarcoidosis patterns. Moreover, there was a reverse correlation between chronicity and ACE level (P-value <0.05). CONCLUSIONS: HRCT is another modality which would be useful when the diagnosis of sarcoidosis is not definite
Comparison of sensitivity and specificity of Wells rule and the revised Geneva score with CT angiography in identifying patients with pulmonary embolism
No full textAbstract
Background and Objective: The use of angiography is the gold standard in the diagnosis of pulmonary embolism (PE). However, the invasive side effects and being less accessible, it is rarely performed. This study sought to determine the sensitivity, specificity, accuracy and positive and negative predictive value of Wells Rule and Revised Geneva Score in identifying patients with pulmonary embolism.
Materials and Methods: This cross-sectional study was performed on 214 patients with suspected pulmonary embolism who referred to Masih Daneshvari Hospital in Tehran, Iran in 2020. The researchers recorded the CT angiographic findings of patients suspected of having pulmonary embolism. All the patients were evaluated based on each of the Wells Rule and revised Geneva score. Finally, the sensitivity and specificity of each score was evaluated in comparison with CT angiography as the gold standard method in the diagnosis of pulmonary embolism.
Results: The overall mean scores of the Revised Geneva Score and Wells Rule were 99.2± 33.6 and 68.2± 96.3, respectively. The sensitivity, specificity and accuracy of the Revised Geneva Score were 90.6, 47.4 and 72%, respectively. The sensitivity, specificity and accuracy of the Wells Rule were 71.8, 75.3 and 77%, respectively. The positive predictive values (PPV) for the Wells Rule and the Revised Geneva Score were 67.5 and 77.8, respectively. Finally, the negative predictive values (NPV) for the Wells Rule and Revised Geneva Score were 80.7 and 68.9, respectively.
Conclusions: The Revised Geneva Score is highly accurate in diagnosing pulmonary embolism. The score could be used as a non-invasive clinical evaluation tool in the diagnosis of PE.
 
Successful Removal of a Pulmonary Foreign Body Using C-Arm-Guided Flexible Bronchoscopy from Distal Airways of a Seven-Year-Old Boy: A Case Report
No full text- …
