Literatura académica sobre el tema "Small-size PTC"
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Artículos de revistas sobre el tema "Small-size PTC"
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LI, Jia-wei, Cai Chang, Jia-ying Chen, Zhao-ting Shi y Min Chen. "Nodule Size Effect on Diagnostic Performance of Ultrasonography and Computed Tomography for Papillary Thyroid Carcinoma". Current Medical Imaging Formerly Current Medical Imaging Reviews 15, n.º 5 (19 de junio de 2019): 489–95. http://dx.doi.org/10.2174/1573405614666180425142141.
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Background: To compare the abilities of ultrasonography (US) and Computed Tomography (CT) to identify calcifications and to predict probability of malignancy for Papillary Thyroid Carcinoma (PTC) and Papillary Thyroid Microcarcinoma (PTMC). Methods: We reviewed 1008 cases of PTC/PTMC with calcifications reported by pre-operative US, CT, or post-operative pathology. The size of the thyroid nodule was obtained from the US report and the maximum diameter (d) was documented. According to the nodule size (d), the PTC and PTMC groups were each divided into two subgroups, as follows: large PTC group (d ≥ 2 cm), small PTC group (1 cm < d < 2 cm), large PTMC group (0.6 cm ≤ d ≤ 1 cm), and small PTMC group (d < 0.6 cm). Results: In the 1008 patients, the ratio of females to males was 2.29 and the mean age was 40.9 years (standard deviation: 11.7 years). Of the 1008 records, 92.8% were found to have calcifications according to the US report, while 50.4% showed calcifications according to the CT report. This difference between US and CT reports was statistically significant (p < 0.0005). The percentages of US reports showing calcifications were similar for all four PTC and PTMC subgroups (93.7%, 94.3%, 92.1%, and 85.1%, respectively; p = 0.052), while the percentages of CT reports showing calcifications were significantly different among the PTC and PTMC subgroups (62.3%, 52.2%, 45.4%, and 31.3%, respectively; p < 0.0005). As for the prediction of malignancy, US was superior to CT in all four subgroups (large PTC group: 97.1% vs. 54.1%, small PTC group: 94.8% vs. 42.9%, large PTMC group: 97.2% vs. 32.0%, small PTMC group: 95.5% vs. 14.9%; p < 0.0005 for all pairwise comparisons). No significant difference was observed in terms of the ability of US to predict the malignancy of PTC versus PTMC (p = 0.31), while CT showed significant superiority in diagnosing PTC versus PTMC (p < 0.0005). The predictive value of CT for PTC declined as the nodule size decreased (p < 0.05 for all pairwise comparisons). Conclusion: Our results showed that US detected calcifications and predicted the malignancy of all nodule sizes of thyroid papillary carcinoma equally well, while the performance of CT declined with the reduction of nodule size.
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Dai, Daofeng, Yawen Tan, Liangfeng Guo, Aifa Tang y Yongsheng Zhao. "Identification of exosomal miRNA biomarkers for diagnosis of papillary thyroid cancer by small RNA sequencing". European Journal of Endocrinology 182, n.º 1 (enero de 2020): 111–21. http://dx.doi.org/10.1530/eje-19-0524.
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Context Exosomal miRNAs are considered potential non-invasive biomarkers for thyroid cancer. However, the global exosomal miRNAs profile for papillary thyroid cancer (PTC) has not been revealed. Objective This study investigated the diagnostic value of plasma and serum exosomal miRNAs for PTC. Methods Plasma and serum samples were collected from ten patients with benign thyroid nodules and 17 with PTC for small RNA sequencing. Plasma samples were collected from two independent cohorts, including 119 patients with PTC, 51 healthy people and 82 patients with benign thyroid nodules, for validation by quantitative reverse-transcription polymerase chain reaction (RT-qPCR). Results Small RNA sequencing identified 41 putative exosomal miRNA biomarkers for PTC. Twelve miRNAs were selected for validation. miR-376a-3p, miR-4306, miR-4433a-5p, and miR-485-3p expression significantly increased in patients with PTC compared to that in healthy people and patients with benign thyroid nodules (P ˂ 0.05). Moreover, miR-485-3p and miR-4433a-5p presented larger areas under the curve (AUCs). The high expression of exosomal miR-485-3p correlated with tumor size greater than or equal to 1 cm, advanced clinical stage, extrathyroidal extension, BRAF mutation, and lymph node metastasis. Besides, miR-485-3p exhibited the highest AUCs in diagnosing PTC patients with high-risk factors. Conclusions Plasma exosomal miR-485-3p and miR-4433a-5p might serve as biomarkers for PTC diagnosis. Plasma exosomal miR-485-3p could enable discrimination between high-risk and low-risk PTC.
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Rodrigues, Evaldo Almeida y Sílvio Albergaria. "Avaliação da capacidade de remoção da camada residual dentinária com o uso do Endo PTC em diferentes formulações, associado a duas concentrações de hipoclorito de sódio, utilizando-se ou não irrigação final com EDTA". Revista de Ciências Médicas e Biológicas 10, n.º 1 (12 de julio de 2011): 44. http://dx.doi.org/10.9771/cmbio.v10i1.4932.
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<p class="MsoNormal" style="line-height: 150%; margin: 0cm 0cm 0pt;"><strong style="mso-bidi-font-weight: normal;"><span style="text-transform: uppercase;"><span style="font-family: Times New Roman; font-size: small;"> </span></span></strong></p><p class="MsoNormal" style="text-align: center; line-height: 150%; margin: 0cm 0cm 0pt;" align="center"><strong style="mso-bidi-font-weight: normal;"><span style="text-transform: uppercase;"><span style="font-size: small;"><span style="font-family: Times New Roman;">Resumo</span></span></span></strong></p><p class="MsoNormal" style="text-align: justify; line-height: 150%; margin: 0cm 0cm 0pt;"><span style="font-family: Times New Roman; font-size: small;"> </span></p>A ação dos instrumentos nas paredes do canal radicular proporciona a formação da camada residual dentinária que, quando não é removida, pode interferir no selamento almejado na etapa da obturação. Algumas substâncias químicas com diferentes composições e variadas concentrações são utilizadas, isoladas ou em associações, para remover essa camada residual. O presente estudo buscou analisar in vitro, através de Microscopia Eletrônica de Varredura, a eficácia, na remoção da camada residual dentinária, de diferentes formulações de Endo PTC, quando associadas a diferentes concentrações de hipoclorito de sódio, utilizando-se ou não irrigação final com EDTA. Foram utilizados oitenta dentes unirradiculares humanos recém-extraídos, divididos aleatoriamente, da seguinte maneira: Grupo I – preparo do canal com Endo PTC creme, associado ao hipoclorito sódio a 1%; Grupo II – preparo do canal como Endo PTC creme, associado ao hipoclorito de sódio a 2,5%; Grupo III – preparo do canal com Endo PTC creme associado ao hipoclorito de sódio a 1% e irrigação final com EDTA a 17%; Grupo IV – preparo do canal com Endo PTC creme associado ao hipoclorito de sódio a 2,5 e irrigação final com EDTA a 17%. Nos Grupos V, VI, VII e VIII foram utilizadas as mesmas substâncias dos grupos I, II, III e IV, respectivamente, substituindo-se o Endo PTC creme pelo Endo PTC Leve. Os resultados mostraram que a irrigação final com EDTA promove uma melhor remoção da camada residual, independentemente da concentração do hipoclorito de sódio e da formulação do Endo PTC.
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Ritter, Amit, Gideon Bachar, Dania Hirsch, Carlos Benbassat, Orna Katz, Nadav Kochen, Talia Diker-Cohen, Amit Akirov, Ilan Shimon y Eyal Robenshtok. "Natural History of Contralateral Nodules After Lobectomy in Patients With Papillary Thyroid Carcinoma". Journal of Clinical Endocrinology & Metabolism 103, n.º 2 (12 de diciembre de 2017): 407–14. http://dx.doi.org/10.1210/jc.2017-01616.
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Abstract Background Bilateral thyroid nodularity is considered an indication for total thyroidectomy in papillary thyroid carcinoma (PTC). However, the natural history and outcome of contralateral nodules have never been studied. Objective To investigate the natural history of nonsuspicious contralateral nodules after lobectomy for PTC. Methods We included patients who had one or more solid nodules (≥3 mm) in the contralateral lobe with benign cytology before surgery or small nonsuspicious nodules per ultrasonography. Results One hundred and twelve patients were included. Median age was 57 years, and median size of the PTC (initial lobectomy) was 8 mm (range, 0.5 to 28 mm). On the contralateral side, the median size of nodules was 7 mm (range, 3 to 30 mm). Thirty-three nodules (29%) had fine-needle aspiration (FNA) before surgery, and all were benign. After a median follow-up of 6 years, median growth was zero (range, −20 to 19 mm). Twenty-six nodules (23%) increased ≥3 mm in size (median, 6 mm; range, 4 to 19 mm). Twenty patients (18%) developed new nodules. Twelve patients (11%) underwent completion thyroidectomy for growth (three), suspicious FNA (seven; Bethesda III to V), malignancy (one), or unknown reason (one). Overall, according to the completion thyroidectomy specimen, six patients (5%) were diagnosed with contralateral PTC (five micro-PTCs, one 20 mm), and all were without evidence of disease at the end of follow-up. There were no surgical difficulties or local complications during completion surgery. Conclusions Lobectomy for low-risk patients with a small PTC and nonsuspicious contralateral thyroid nodule(s) is a reliable and safe initial treatment option. In the few patients who required completion thyroidectomy, treatment with surgery and radioiodine was effective.
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Hurmuz, Pervin, Mustafa Cengiz, Gokhan Ozyigit, Ebru Atasever Akkas, Deniz Yuce, Melek Tugce Yilmaz, Demet Yildiz, Faruk Zorlu y Fadil Akyol. "Stereotactic body radiotherapy in patients with early-stage non-small cell lung cancer: Does beam-on time matter?" Japanese Journal of Clinical Oncology 50, n.º 10 (16 de junio de 2020): 1182–87. http://dx.doi.org/10.1093/jjco/hyaa093.
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Abstract Purpose Stereotactic body radiotherapy (SBRT) is an effective treatment option for patients with early-stage non-small cell lung cancer (NSCLC). In this study, we evaluated the treatment results using two different SBRT techniques and the effect of beam-on time (BOT) on treatment outcomes. Methods Between July 2007 and January 2018, 142 patients underwent SBRT for primary NSCLC. We have delivered SBRT using either respiratory tracking system (RTS) or internal-target-volume (ITV)-based motion management techniques. The effect of age, tumor size, pretreatment tumor SUVmax value, presence of tissue diagnosis, histopathological subtype, operability status, tumor location, motion management technique, BED10 value, BOT on overall survival (OS), loco-regional control (LRC), event-free survival (EFS) and primary tumor control (PTC) were evaluated. Results Median age of the patients was 70 years (range, 39–91 years). Most of the patients were inoperable (90%) at the time of SBRT. Median BED10 value was 112.5 Gy. With a median follow-up of 25 months, PTC was achieved in 91.5% of the patients. Two-year estimated OS, LRC, PTC and EFS rates were 68, 63, 63 and 53%, respectively. For the entire group, OS was associated with BOT (P = 0.027), and EFS was associated with BOT (P = 0.027) and tumor size (P = 0.015). For RTS group, OS was associated with age (P = 0.016), EFS with BOT (P = 0.05) and tumor size (P = 0.024), LRC with BOT (P = 0.008) and PTC with BOT (P = 0.028). The treatment was well tolerated in general. Conclusion SBRT is an effective and safe treatment with high OS, LRC, EFS and PTC rates in patients with primary NSCLC. Protracted BOT might deteriorate SBRT outcomes.
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Bayadsi, Haytham, Martin Bergman, Malin Sund y Joakim Hennings. "Invasiveness and Metastatic Aggressiveness in Small Differentiated Thyroid Cancers: Demography of Small Papillary Thyroid Carcinomas in the Swedish Population". World Journal of Surgery 44, n.º 2 (13 de diciembre de 2019): 461–68. http://dx.doi.org/10.1007/s00268-019-05312-4.
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Abstract Background The western world is seeing a rising incidence of thyroid cancer. Improved diagnostic methods do not entirely explain this increase. Papillary thyroid carcinoma (PTC) is the most common subtype of thyroid cancer. Small PTC (≤20 mm) and especially papillary thyroid microcarcinomas (PTMC ≤10 mm) are considered to be low-risk tumors but some cases are considerably more aggressive. Sufficient understanding of these mechanisms is a long-term goal for more efficient and safer treatment of these tumors. Methods We identified 959 cases of small PTCs in the validated Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery, grouped according to lymph node metastasis. These were analyzed according to age, gender, tumor size and geographic region. Results Patients with N1b disease (lateral lymph nodes metastases) had a smaller tumor size compared to patients with N1a disease (8.6 mm vs 10.1 mm respectively, p < 0.05). Patients and specifically females with N1b disease were younger than those with N0 or N1a disease. Patients with N1b disease had a lower proportion of females (60%) compared to N0 and N1a groups (81% and 78%, respectively). The incidence of operated small PTCs and of lymph node engagement differs between geographic regions in Sweden. Conclusions Small PTC and especially PTMC seem to show different patterns of aggressiveness and demography regarding lateral lymph node metastases and 7% had N1b disease and tumor <1 cm, underscoring the importance of lymph node evaluation in PTMC patients. More understanding of predictive factors, mechanisms for metastatic disease and causes of regional differences, is needed.
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Lang, Brian Hung-Hin, Young Jun Chai, Benjamin J. Cowling, Hye Sook Min, Kyu Eun Lee y Yeo-Kyu Youn. "Is BRAFV600E mutation a marker for central nodal metastasis in small papillary thyroid carcinoma?" Endocrine-Related Cancer 21, n.º 2 (8 de enero de 2014): 285–95. http://dx.doi.org/10.1530/erc-13-0291.
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Utilizing BRAFV600E mutation as a marker may reduce unnecessary prophylactic central neck dissection (pCND) in clinically nodal negative (cN0) neck for small (≤2 cm) classical papillary thyroid carcinoma (PTC). We aimed to assess whether BRAF is a significant independent predictor of occult central nodal metastasis (CNM) and its contribution to the overall prediction after adjusting for other significant preoperative clinical factors in small PTC. Primary tumor tissue (paraffin-embedded) from 845 patients with small classical cN0 PTC who underwent pCND was tested for BRAF mutation. Clinicopathologic factors were compared between those with and without BRAF. BRAF was evaluated to see if it was an independent factor for CNM. Prediction scores were generated using logistic regression models and their predictability was measured by the area under the ROC curve (AUC). The prevalence of BRAF was 628/845 (74.3%) while the rate of CNM was 285/845 (33.7%). Male sex (odds ratio (OR): 2.68, 95% CI: 1.71–4.20), large tumor size (OR: 2.68, 95% CI: 1.80–4.00), multifocality (OR: 1.49, 95% CI: 1.07–2.09), lymphovascular permeation (OR: 10.40, 95% CI: 5.18–20.88), and BRAF (OR: 1.65, 95% CI: 1.10–2.46) were significant independent predictors of CNM, while coexisting Hashimoto's thyroiditis (OR: 0.56, 95% CI: 0.40–0.80) was an independent protective factor. The AUC for prediction score based on tumor size and male sex was similar to that of prediction score based on tumor size, male sex, and BRAF status (0.68 vs 0.69, P=0.60). Although BRAF was an independent predictor of CNM, knowing its status did not substantially improve the overall prediction. A simpler prediction score based on male sex and tumor size might be sufficient.
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Ryu, Young-Jae, Seong-Young Kwon, Soo-Young Lim, Yong-Min Na y Min-Ho Park. "Predictive Factors for Skip Lymph Node Metastasis and Their Implication on Recurrence in Papillary Thyroid Carcinoma". Biomedicines 10, n.º 1 (16 de enero de 2022): 179. http://dx.doi.org/10.3390/biomedicines10010179.
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Skip lymph node (LN) metastases in papillary thyroid carcinoma (PTC) belong to N1b classification in the absence of central neck LN involvement. This study aimed to evaluate the predictive factors of skip metastases and their impact on recurrence in PTC patients with pN1b. A total of 334 PTC patients who underwent total thyroidectomy with LN dissection (central and lateral neck compartment) followed by radioactive iodine ablation were included. Patients with skip metastases tended to have a small primary tumor (≤1 cm) and single lateral neck level involvement. Tumor size ≤ 1 cm was an important predictive factor for skip metastases. Univariate analysis for recurrence showed that patients with a central LN ratio > 0.68, lateral LN ratio > 0.21, and stimulated thyroglobulin (Tg) levels > 7.3 ng/mL had shorter RFS (recurrence-free survival). The stimulated Tg level was associated with shorter RFS on multivariate analysis (>7.3 vs. ≤7.3 ng/mL; hazard ratio, 4.226; 95% confidence interval, 2.226−8.022; p < 0.001). Although patients with skip metastases tended to have a small primary tumor and lower burden of lateral neck LN involvement, there was no association between skip metastases and RFS in PTC with pN1b. Stimulated Tg level was a strong predictor of recurrence.
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Conway, Jessica M. y Alan S. Perelson. "Post-treatment control of HIV infection". Proceedings of the National Academy of Sciences 112, n.º 17 (13 de abril de 2015): 5467–72. http://dx.doi.org/10.1073/pnas.1419162112.
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Antiretroviral therapy (ART) for HIV is not a cure. However, recent studies suggest that ART, initiated early during primary infection, may induce post-treatment control (PTC) of HIV infection with HIV RNA maintained at <50 copies per mL. We investigate the hypothesis that ART initiated early during primary infection permits PTC by limiting the size of the latent reservoir, which, if small enough at treatment termination, may allow the adaptive immune response to prevent viral rebound (VR) and control infection. We use a mathematical model of within host HIV dynamics to capture interactions among target cells, productively infected cells, latently infected cells, virus, and cytotoxic T lymphocytes (CTLs). Analysis of our model reveals a range in CTL response strengths where a patient may show either VR or PTC, depending on the size of the latent reservoir at treatment termination. Below this range, patients will always rebound, whereas above this range, patients are predicted to behave like elite controllers. Using data on latent reservoir sizes in patients treated during primary infection, we also predict population-level VR times for noncontrollers consistent with observations.
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Ognerubov, N. A. y T. S. Antipova. "Metastases of papillary radioiodine-refractory thyroid cancer in the parapharyngeal lymph node: clinical case". Head and Neck Tumors (HNT) 11, n.º 1 (24 de abril de 2021): 115–21. http://dx.doi.org/10.17650/2222-1468-2021-11-1-115-121.
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Introduction. Papillary thyroid cancer (PTC) usually metastasizes into the central and lateral lymph nodes (LNs) of the neck. Metastases into the retropharyngeal and parapharyngeal LNs are rare. Their presence attests to aggressive PTC.The study objective is to describe a rare case of metastases of papillary radioiodine-refractory PTC into the parapharyngeal LN.Clinical case. In 2015, female patient K., 40 years old, underwent thyroidectomy due to PTC. Histological examination verified papillary PTC with growth through the capsule and ingrowth into the surrounding tissues and muscles. In a separately admitted LN, metastases of the same cancer were observed. One year later, regional metastases in the lateral neck LNs were detected. Radioiodine therapy (activity 131I 4.5 GBq) was performed followed by fascial circular section of the neck tissues on the right per thyroid type. Morphological examination verified presence of papillary PTC metastases in 4 LNs. In January of 2018, positron emission tomography showed metastases in the paratracheal LNs. Central neck lymph node dissection was performed. Per histological conclusion, fat tissue and LN contained multiple metastases of papillary PTC. In October of the same year, repeat radioiodine therapy (activity 131I 3.0 GBq) was performed. Thyroglobulin levels increased. In June of 2020, repeat positron emission tomography showed a single metastasis in the parapharyngeal LN. Due to small size of the metastasis and absence of signs of progression, dynamic follow-up and hormone therapy were suggested to the patient.Conclusion. Metastatic involvement of parapharyngeal LNs is rare, especially in radioiodine-refractory PTC. They can be detected both during primary diagnosis and after the treatment during dynamic follow-up, as well as a single manifestation of PTC, which should be taken into account during differential diagnosis.
Tesis sobre el tema "Small-size PTC"
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Hosouli, Sahand. "Experimental and Computational Analysis of Small-Size Solar Receiver for Industrial and Residential Application". Doctoral thesis, 2021. http://hdl.handle.net/2158/1238638.
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Use of solar thermal energy in residential and industrial applications has to be sustained to reduce the concentration of greenhouse gas in atmosphere due to the exploitation of fossil fuels in producing energy. In this context, the renewable energies play an important role. The energy request in industrial and residential sector involves a noticeable fraction (more than 50%) of the total requested supply for human activities. Concentrating collectors could be the right technology to produce heat at medium temperature (between 85 and 250°C) to provide thermal energy to users with high consumption rates and low-temperature heat demand like domestic hot water and space heating in addition to the industrial process heat applications.
Thus, in this study UF-RT01 receiver (University of Florence Receiver Tube 01) of small size parabolic trough collector called m-PTC were investigated experimentally by indoor and outdoor tests and computationally by 3D heat transfer FEM model. The m-PTC suitable to be integrated in the roof of industrial environments where the space for installation of solar collectors is in general limited and the heat demand temperature is below than 200°C.
The UF-RT01 receiver has a specific design, being formed by two coaxial tubes so that the fluid inlet and output are at the same side. It was properly developed to scale the PTC technology toward smaller size (chord length from 6-8 meters to around 0.5 m): the purpose is the installation in urban context and the application in industrial process. The outer absorber tube is made of steel and has a diameter of 10 mm (1 mm thickness) for a length of 1860 mm; the smaller coaxial tube is made of steel and has an internal diameter of 6 mm (0.5 mm thickness). Furthermore, a selective coating has been selected to reduce the emission in infrared range and increase the energy absorption in solar spectral range. Inside, a vacuum level is fixed at 10-4 mbar to reduce the heat losses to the radiative ones.
In order to study the thermal losses of the receiver, two different indoor test stand have been realized. The thermal loss measurement is set up under indoor test without Sun irradiance, imposing a controlled internal heating. This process is based on the Joule effect, feeding electric heaters with current to obtain a steady state condition at different reference temperatures. In preliminary test stand by removing the inner coaxial steel tube, two nickel-chrome wire heaters are inserted along the length of absorber tube. An additional external heater is also placed before the Kovar part to meet the adiabatic condition and minimizing the temperature gradient. The UF-RT01 has been analyzed experimentally and performances are evaluated as a function of different operating temperatures, reaching up to 180°C. A maximum value for heat loss amounts at about 24 W when ΔT is 161°C (receiver average temperature of 180°C). In order to obtain more uniformity of temperature along the absorber tube the second test set up has been developed for thermal loss measurement and instead of nickel-chrome wire heater, an industrial cartridge heater made of resistance wire (NiCr20/80) as a core covered with stainless steel 304 as a sleeve (sheath) has been used. Three different tube from same type (UF-RT01) have been tested in the range of interest and the procedure was repeated for about 150 cases. In comparison to preliminary test stand, results showed more uniformity in temperature distribution along the tube. A maximum value of 17.89 W is found when ΔT is 163°C (receiver average temperature of 190°C).
In order to achieve production assurance and have more clear vision about the results due to the different results obtained from test on RT03 in comparison to the RT01 and RT02 with higher thermal loss, new tests have been conducted on additional tubes. Similar setup and test procedure have been conducted in order to evaluate the uniformity of temperature along the tube and estimate the heating supplier parameters in additional tubes. Seven different tube from same type have been tested and labeled as RT04-RT10. Results from tests on RT01 and RT02 are in accordance with new results obtained from heat loss test on RT04-RT10. Therefore, the different results related to the RT03 are to be expected as a result of variation in production quality by manufacturer of receiver tube.
The Finite Element Method (FEM) has been used in order to predict the thermal performance and analyze the relevant physical characteristics of the receiver tube (specially the value of emissivity at higher temperature). Heat transfer model using FEM simulation method has been realized with Comsol Multiphysics software. An adaptive mesh refinement (AMR) with different mesh configurations has been conducted in order to increase storage and computational savings. By using a parametric sweep to vary the maximum element size, the model solved using meshes with different mesh density in order to study how it affects the solution. The heat transfer model is able to precisely predict the heat losses at low temperature of the absorber tube with constant value of emissivity reported by manufacturer. The estimation of emissivity at the higher temperature obtained by solving the model with various emissivity values for each test at specific input power until the average temperature inside the absorber tube obtained by simulation were in agreement with experimental value. The obtained emissivity function has been used in model in order to solve the model for various input power values and the results showed that the model and emissivity function are able to predict the thermal loss with high accuracy.
In order to perform the out-door test according the designed and assembled test rig platform at first phase has been slightly modified to reduce the heat losses and reach stable inlet temperature . The reliability of implemented test bench and output power and efficiency of a novel small size parabolic trough collector have been evaluated by preliminary test. For this purpose an out-door tests at ambient temperature on the designed small size PTC test rig is carried out during clear sky day. Furthermore, the peak optical efficiency test has been conducted based on introduced requirements at quasi-steady condition. The general point of the outdoor efficiency test is extracting the efficiency curve of the collector for normal incidence based on the efficiency curve coefficients. 24 tests have been done under various inlet temperature and irradiance under clear sky condition and the exemplary performance measurement data for present research stems from 153 experimental points.
The preliminary out-door experimental test on the collectors showed that the test rig meets the initial design expectations in order to control the system in stable condition. The peak optical efficiency test has been conducted at quasi-steady condition and the average peak optical efficiency of the collector is 61.8% with total absolute error of 1.4%. With regard to the peak optical efficiency and for assuring that experimental results from the outdoor testing are valid, a cross check with the efficiency curve of the collector by weighted least squares (WLS) fitting shows almost similar values. The obtained value for peak optical efficiency from efficiency curve is 62.1%. Efficiency measurement of solar collector have been conducted from inlet temperature of 28 °C up to 123°C for various DNI values. A Maximum of 63.1% for thermal efficiency is found when the inlet temperature is 28.41°C and a minimum of 54.6% corresponds at 122.90°C. The total standard absolute uncertainty of thermal efficiency for test at inlet temperature of 28.41°C and 122.90°C are 0.7% and 0.8%, respectively. The efficiency curve of the collector by WLS fitting were also obtained from outdoor test results.
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"Planning process in small and medium size firms: a case study of two garment companies in espirito santo state". Tese, MAXWELL, 1994. http://www.maxwell.lambda.ele.puc-rio.br/cgi-bin/db2www/PRG_0991.D2W/SHOW?Cont=1777:pt&Mat=&Sys=&Nr=&Fun=&CdLinPrg=pt.
Texto completoCapítulos de libros sobre el tema "Small-size PTC"
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Kushilevitz, Eyal y Tamer Mour. "Sub-logarithmic Distributed Oblivious RAM with Small Block Size". En Public-Key Cryptography – PKC 2019, 3–33. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-17253-4_1.
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Åsheim, Henrik, Thor A. Aarhaug, Alain Ferber, Ole S. Kjos y Geir M. Haarberg. "Monitoring of Continuous PFC Formation in Small to Moderate Size Aluminium Electrolysis Cells". En Light Metals 2014, 535–39. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118888438.ch91.
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Åsheim, Henrik, Thor A. Aarhaug, Alain Ferber, Ole S. Kjos y Geir M. Haarberg. "Monitoring of Continuous PFC Formation in Small to Moderate Size Aluminium Electrolysis Cells". En Light Metals 2014, 535–39. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-48144-9_91.
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Chen, Zhao y Ming Lu. "Urban System and Urban Development in the People’s Republic of China". En Cities of Dragons and Elephants, 81–102. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198829225.003.0004.
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There is a trend of population concentration towards large coastal cities in The People’s Republic of China (PRC). However, there is a distortion of city size towards small cities in the PRC. That is to say, urban population in China should further concentrate in large cities rather than be more equally spread out. Cross-country analysis also indicates that the population size of the primary city in the PRC is smaller than its predicted value. The discussion in this chapter suggests that the Chinese government should adjust the policies on future urbanization with fewer restrictions on the further growth of megacities.
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Samanta, Eshan, Arif Ahmed Sekh y Debnarayan Khatua. "An Expert System-Based Automation in Indian Traction System for a One Way Single Platform Station by Introducing PLC". En Advances in Systems Analysis, Software Engineering, and High Performance Computing, 213–30. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-2584-5.ch013.
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Nowadays, it is very often that some portion of the Indian traction system is still suffering from a single line railway transportation. This in turn creates a havoc disturbance in maintaining the proper sequence of traction control system. Also, passengers are taking risk to catch the train which is already in motion but no such action has been taken to eliminate these consequences. It has been found that more or less various works have been done on Automation in Railway Crossing Gate using Microcontroller and IR Sensor. Thus, it is often decided to develop an idea for the Indian traction system to ensure better controlling action by introducing Limit Switches as Tactile Sensors and by introducing HMI using PLC. The purpose here to take control over various controlling domains, including Railway crossing gate are as follows: Track signal, crossing level signal, alarm notification, and platform edge fence. The proper sequencing needs to be operated via a 128 I/O module with 2 KB memory size small PLC kit.
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Samanta, Eshan, Arif Ahmed Sekh y Debnarayan Khatua. "An Expert System-Based Automation in Indian Traction System for a One Way Single Platform Station by Introducing PLC". En Research Anthology on Cross-Disciplinary Designs and Applications of Automation, 1039–54. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-3694-3.ch051.
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Nowadays, it is very often that some portion of the Indian traction system is still suffering from a single line railway transportation. This in turn creates a havoc disturbance in maintaining the proper sequence of traction control system. Also, passengers are taking risk to catch the train which is already in motion but no such action has been taken to eliminate these consequences. It has been found that more or less various works have been done on Automation in Railway Crossing Gate using Microcontroller and IR Sensor. Thus, it is often decided to develop an idea for the Indian traction system to ensure better controlling action by introducing Limit Switches as Tactile Sensors and by introducing HMI using PLC. The purpose here to take control over various controlling domains, including Railway crossing gate are as follows: Track signal, crossing level signal, alarm notification, and platform edge fence. The proper sequencing needs to be operated via a 128 I/O module with 2 KB memory size small PLC kit.
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Rodríguez, Noé Becerra y Gabriela Dutrénit Bielous. "Exploring the Impact of University-Industry Linkages on Firms' Innovation". En Handbook of Research on Driving Competitive Advantage through Sustainable, Lean, and Disruptive Innovation, 590–613. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-5225-0135-0.ch024.
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This chapter explores the impact of University-Industry Linkages (UIL) on the innovative performance of Mexican firms. Due the diverse nature of universities and public research centers, it examines the effect of those UIL separately. Using original data from a survey of 382 firms, the outcomes of Logistic regressions indicate that UIL have significant but mixed effects on firms' innovation. While links with universities seem to enhance product innovations, interactions with PRC seem to foster process innovations. The results confirm the major impact formal Research and Development (R&D) has on innovation projects. Regarding technological intensity, a significant influence on product innovation was found, but not on process novelties with high-technology firms performing better than those from the low technology and services sectors. Conversely, size and age have notable influence on process innovation but not on product novelties, with larger and younger firms innovating more than small and older ones. Finally, some political implications are discussed.
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Lucchesi, John C. "Nuclear bodies". En Epigenetics, Nuclear Organization & Gene Function, 153–62. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198831204.003.0013.
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The nucleus is subdivided into a number of compartments that are not enclosed by membranes and whose main functions are transcriptional regulation and RNA processing. Many of the same proteins are found in different compartments, highlighting the dynamic exchange of components. The perinuclear compartment (PNC) is a hallmark of a number of different cancers. Cajal bodies (CBs) are sites of assembly of small nuclear ribonucleic particles (snRNPs) that function in messenger RNA (mRNA) or ribosomal RNA (rRNA) processing and in the biogenesis of telomerase. Nuclear speckles contain pre-mRNA splicing components and proteins involved in every aspect of gene regulation. Paraspeckles are involved in the processing and maturation of micro RNAs (miRNAs). Promyelocytic leukemia (PML) nuclear bodies contain the PML protein that has tumor suppressor activity by preventing the inactivation of p53. Under conditions of stress, the number and size of PML nuclear bodies increases. Transcription factories are nuclear regions where several RNA polymerase II (RNAPII) complexes are transcribing several genes. The co-localization of genes in transcription factories may lead to their co-regulation.
Actas de conferencias sobre el tema "Small-size PTC"
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Furuichi, Noriyuki, Kar-Hooi Cheong, Yoshiya Terao, Shinichi Nakao, Keiji Fujita, Kazuo Shibuya, Leopoldo Cordova y Thomas Lederer. "Experimental Results of Flow Nozzle Based on PTC 6 for High Reynolds Number". En ASME 2014 Power Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/power2014-32116.
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Discharge coefficients for three flow nozzles based on ASME PTC 6 are measured under many flow conditions at AIST, NMIJ and PTB. The uncertainty of the measurements is from 0.04% to 0.1% and the Reynolds number range is from 1.3×105 to 1.4×107. The discharge coefficients obtained by these experiments is not exactly consistent to one given by PTC 6 for all examined Reynolds number range. The discharge coefficient is influenced by the size of tap diameter even if at the lower Reynolds number region. Experimental results for the tap of 5 mm and 6 mm diameter do not satisfy the requirements based on the validation procedures and the criteria given by PTC 6. The limit of the size of tap diameter determined in PTC 6 is inconsistent with the validation check procedures of the calibration result. An enhanced methodology including the term of the tap diameter is recommended. Otherwise, it is recommended that the calibration test should be performed at as high Reynolds number as possible and the size of tap diameter is desirable to be as small as possible to obtain the discharge coefficient with high accuracy.
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Le Galudec, Olivier, James Oszewski, John Preston y David Thimsen. "Introducing ASME PTC 48". En ASME 2014 Power Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/power2014-32067.
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In the field of Power Generation, Operators — Plant Owners, Utilities, IPPs … — have had to face severe constraints linked not only with price of electricity and cost of fuel, but also with more and more demanding environmental constraints. It appears that the next atmospheric emission coming under scrutiny is CO2. Some small scale laboratory size experiments and pilot scale tests demonstrating the ability to capture CO2 before it reaches the atmosphere have already been conducted, and some industrial scale demonstrators are already at the permitting stage and will soon reach construction. In order to anticipate the needs of Performance Tests within this coming market, ASME decided to form a new committee in order to prepare and deliver ASME Performance Test Code – PTC 48 “Overall Plant Performance with Carbon Capture” test code. This new code may be seen as an evolution of ASME PTC 46 “Performance Test Code on Overall Plant Performance” 1996 (currently under revision), which goes beyond the sole verification of components to provide guidelines for testing a full Plant. Capturing CO2 from fuel–fired power plants will have a significant impact on net capacity and net heat rate of the plant. Such plants will, in addition to the Power Block and Steam Generator, also include systems not commonly included in non-CO2 capture power plants. The addition of an ASU (Air Separation Unit, for oxy-combustion with CO2 capture) and/or CPU (CO2 Purification Unit, for oxy-combustion or post-combustion CO2 capture) has made necessary the preparation of a dedicated test code based upon same guiding principle than PTC 46, i.e. treating the plant globally as a “Black Box”. This approach allows correction of output and efficiency at the plant interfaces, but at the exclusion of internal parameters. It is anticipated that the code can inform development of regulations that define the rules and obligations of Operators. Currently, the proposed PTC 48 aims at fossil fuel fired Steam-electric power plants using either post-combustion CO2 capture or oxy-combustion with CO2 capture technologies. Combined cycles and Integrated Gasification Combined Cycles — IGCCs — are not addressed.
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Bassand, J. P., J. Machecourt, J. Cassagnes, J. R. Lusson, P. Bourlard, T. Anguenot, J. Faivre, J. E. Wolff y J. Peycelon. "ACYL PLASMINOGEN STREPTOKINASE VERSUS HEPARIN IN RECENT ACUTE MYOCARDIAL INFARCTION. PRELIMINARY REPORT OF A FRENCH INTERUNIVERSITY TRIAL". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643622.
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One hundred and twenty seven patients (pts) suffering from a first acute myocardial infarction (AMI) were included in a multicenter trial involving three University Hospitals and 22 community Hospitals without catheterization facilities. Patientswere randomly allocated within 5 hours following the onset of symptoms either to acyl plasminogen streptokinase (APSAC) 30 IU within 5 min followed 4 hours later by heparin at a dose of 500 IU/kg/day or to conventional Heparin (H) therapy 500 IU/kg/day. 63 pts received APSAC and 64 received H. Both APSAC and H groups were similar in age, location of AMI, Killip class and time of randomization. After initial therapy Pts were referred to the University Hospitals and submitted between Day 1 and Day 7 to a selective coronary angiography and immediate percutaneous transluminal angioplasty (PTCA) of the infarct-related artery if suitable for the procedure.4 APSAC pts and 2 H pts died during the hospital course (NS).The arterial patency rate determined on average 3.4 ± 1.2 days after the onset of symptoms was 88% in APSAC and 42% in H (P<.001). 15 APSAC pts and7 H pts were submitted to PTC A with one failure in each group. LVEF and akinetic score (AK) were determined from left ventricular angioeraDhy :On Day 14, pts were submitted to Ti 201 scan and to radionuclide angiography (RNA). Results are not yet available.Our results showed that early infusion of APSAC in AMI produced a high short term patency-rate of the IRA with a tendancy toward improvement of the left ventricular systolic function which failed to reach statistical significance because of the relatively small size of the cohort.
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Kekez, Mladen M. "Understanding the HPM generation in atmospheric air with reference to small-size MCG". En 2009 IEEE Pulsed Power Conference (PPC). IEEE, 2009. http://dx.doi.org/10.1109/ppc.2009.5386318.
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Grant, Emanuel S. y Jason M. Hicks. "Benefits of Small Size Classes in Graduate Software Engineering Education". En 2020 IEEE International Conference on Progress in Informatics and Computing (PIC). IEEE, 2020. http://dx.doi.org/10.1109/pic50277.2020.9350826.
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Sitjongsataporn, Suchada y Nattapong Paenoi. "Small and Medium-sized Enterprise Cockle Size Sorting Machine using PLC System". En 2021 International Conference on Power, Energy and Innovations (ICPEI). IEEE, 2021. http://dx.doi.org/10.1109/icpei52436.2021.9690656.
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Hiramatsu, S., H. Iwasaki, T. Mitsuhashi, T. Naitoh y Y. Yamamoto. "Measurement of small beam size by the use of SR interferometer". En Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366). IEEE, 1999. http://dx.doi.org/10.1109/pac.1999.795741.
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Guyon, Olivier, Stephen Ridgway, Claude Aime, Anthony Boccaletti, Jean-Luc Beuzit, Raphael Galicher, Pierre Kern et al. "Pupil Remapping Coronagraph (PRC): a high-performance coronagraph for a small-size visible Terrestrial Planet Finder". En SPIE Astronomical Telescopes + Instrumentation, editado por John C. Mather. SPIE, 2004. http://dx.doi.org/10.1117/12.552429.
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ASSAD, M. S., O. G. PENYAZKOV, I. I. CHERNUHO y K. ALHUSSAN. "PROPAGATION OF THE BURNING WAVE IN A PULSED DETONATION COMBUSTOR OPERATING ON MIXTURES OF HEPTANE AND JET A-1 WITH AIR AND OXYGEN AT [O2/AIR] < 1". En 12TH INTERNATIONAL COLLOQUIUM ON PULSED AND CONTINUOUS DETONATIONS. TORUS PRESS, 2020. http://dx.doi.org/10.30826/icpcd12a21.
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This work is devoted to the study of the dynamics of combustion wave propagation in oxygen-enriched mixtures of n-heptane with air and jet fuel "Jet A-1" in a small-size pulsed detonation combustor (PDC) with a diameter of 20 mm and a length less than 1 m. Experiments are carried out after the PDC reaches a stationary thermal regime when changing the equivalence ratio (ϕ = 0.73-1.89) and the oxygen-to-air ratio ([O2/air] = 0.15-0.60). The velocity of the combustion wave is determined by measuring the propagation time of the flame front between adjacent pressure sensors that form measurement segements along the PDC.
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Zhenliang, Chen, Shi Huaizhong, Chen Han, Wang Zhenquan, Huang Zhongwei y Song Xianzhi. "Experimental Study of Conglomerate-Breaking Characteristics of Axe-Shaped PDC Cutter". En 56th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2022. http://dx.doi.org/10.56952/arma-2022-2106.
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ABSTRACT: Conventional PDC cutters are prone to get broken when drilling through conglomerate formations and soft-hard interbedded heterogeneous layers, leading to serious fatigue wear, short bit life, and small bit footage. Compared to the conventional PDC cutter, axe-shaped PDC cutter can dig out gravel and pebbles through crushing and shearing, which significantly reduces energy consumption for rock-breaking. Thus, this paper proposed to study effects of axe-shaped PDC cutter cutting parameters on rock-breaking characteristics of conglomerates. Using PDC cutter cutting equipment, the research quantitatively revealed the effects of cutting depth, back rake angle, and cutting speed on the cutting force, cutting size distribution, and the groove morphological characteristics of axe-shaped PDC cutter. Also, mechanical modeling was used to describe the mechanical dynamics of the axeshaped PDC cutter in the cutting process. Then, an axe-shaped PDC bit was designed and manufactured, for the purpose of field application. According to the testing data, the cutting force of the axe-shaped PDC cutter increases with increasing back rake angle and increasing cutting depth. The larger the cutting angle, the more complicated the relationship between the cutting force amplitude and the cutting depth, from linear relation to quadratic and cubic functions. Meanwhile, the mechanical specific energy for rock-breaking remains at a small level in a cutting angle range of 10 to 20 °. Compared with the conventional PDC bit, the bit footage of PDC bit with ASP-cutter increased by 399m and the average ROP increased by 24.22%. These findings are expected to provide theoretical guidance on the rock-breaking characteristics of axe-shaped PDC cutter, especially for the drilling process in conglomerate formation. INTRODUCTION Since PDC bit was introduced into the oil and gas drilling industries in 1970s by GENERAL Electric of the United States, it has been widely used in drilling soft to medium-hard formations with high rock-breaking efficiency and long service life (Yang and Guo 2018). However, in the drilling process of conglomerates and other heterogeneous layers (e.g. soft-hard interbedded layers), conventional PDC cutters are easily to get broken and prone to crack, leading to premature failure of drill bit, low drilling efficiency and high drilling cost (He et al. 2021; Zeng et al. 2021).
Informes sobre el tema "Small-size PTC"
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Harris, L. B., P. Adiban y E. Gloaguen. The role of enigmatic deep crustal and upper mantle structures on Au and magmatic Ni-Cu-PGE-Cr mineralization in the Superior Province. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328984.
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Aeromagnetic and ground gravity data for the Canadian Superior Province, filtered to extract long wavelength components and converted to pseudo-gravity, highlight deep, N-S trending regional-scale, rectilinear faults and margins to discrete, competent mafic or felsic granulite blocks (i.e. at high angles to most regional mapped structures and sub-province boundaries) with little to no surface expression that are spatially associated with lode ('orogenic') Au and Ni-Cu-PGE-Cr occurrences. Statistical and machine learning analysis of the Red Lake-Stormy Lake region in the W Superior Province confirms visual inspection for a greater correlation between Au deposits and these deep N-S structures than with mapped surface to upper crustal, generally E-W trending, faults and shear zones. Porphyry Au, Ni, Mo and U-Th showings are also located above these deep transverse faults. Several well defined concentric circular to elliptical structures identified in the Oxford Stull and Island Lake domains along the S boundary of the N Superior proto-craton, intersected by N- to NNW striking extensional fractures and/or faults that transect the W Superior Province, again with little to no direct surface or upper crustal expression, are spatially associated with magmatic Ni-Cu-PGE-Cr and related mineralization and Au occurrences. The McFaulds Lake greenstone belt, aka. 'Ring of Fire', constitutes only a small, crescent-shaped belt within one of these concentric features above which 2736-2733 Ma mafic-ultramafic intrusions bodies were intruded. The Big Trout Lake igneous complex that hosts Cr-Pt-Pd-Rh mineralization west of the Ring of Fire lies within a smaller concentrically ringed feature at depth and, near the Ontario-Manitoba border, the Lingman Lake Au deposit, numerous Au occurrences and minor Ni showings, are similarly located on concentric structures. Preliminary magnetotelluric (MT) interpretations suggest that these concentric structures appear to also have an expression in the subcontinental lithospheric mantle (SCLM) and that lithospheric mantle resistivity features trend N-S as well as E-W. With diameters between ca. 90 km to 185 km, elliptical structures are similar in size and internal geometry to coronae on Venus which geomorphological, radar, and gravity interpretations suggest formed above mantle upwellings. Emplacement of mafic-ultramafic bodies hosting Ni-Cr-PGE mineralization along these ringlike structures at their intersection with coeval deep transverse, ca. N-S faults (viz. phi structures), along with their location along the margin to the N Superior proto-craton, are consistent with secondary mantle upwellings portrayed in numerical models of a mantle plume beneath a craton with a deep lithospheric keel within a regional N-S compressional regime. Early, regional ca. N-S faults in the W Superior were reactivated as dilatational antithetic (secondary Riedel/R') sinistral shears during dextral transpression and as extensional fractures and/or normal faults during N-S shortening. The Kapuskasing structural zone or uplift likely represents Proterozoic reactivation of a similar deep transverse structure. Preservation of discrete faults in the deep crust beneath zones of distributed Neoarchean dextral transcurrent to transpressional shear zones in the present-day upper crust suggests a 'millefeuille' lithospheric strength profile, with competent SCLM, mid- to deep, and upper crustal layers. Mechanically strong deep crustal felsic and mafic granulite layers are attributed to dehydration and melt extraction. Intra-crustal decoupling along a ductile décollement in the W Superior led to the preservation of early-formed deep structures that acted as conduits for magma transport into the overlying crust and focussed hydrothermal fluid flow during regional deformation. Increase in the thickness of semi-brittle layers in the lower crust during regional metamorphism would result in an increase in fracturing and faulting in the lower crust, facilitating hydrothermal and carbonic fluid flow in pathways linking SCLM to the upper crust, a factor explaining the late timing for most orogenic Au. Results provide an important new dataset for regional prospectively mapping, especially with machine learning, and exploration targeting for Au and Ni-Cr-Cu-PGE mineralization. Results also furnish evidence for parautochthonous development of the S Superior Province during plume-related rifting and cannot be explained by conventional subduction and arc-accretion models.