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Doak, Thomas G., David J. Witherspoon, Carolyn L. Jahn, and Glenn Herrick. "Selection on the Genes of Euplotes crassus Tec1 and Tec2 Transposons: Evolutionary Appearance of a Programmed Frameshift in a Tec2 Gene Encoding a Tyrosine Family Site-Specific Recombinase." Eukaryotic Cell 2, no. 1 (February 2003): 95–102. http://dx.doi.org/10.1128/ec.2.1.95-102.2003.
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ABSTRACT The Tec1 and Tec2 transposons of the ciliate Euplotes crassus carry a gene for a tyrosine-type site-specific recombinase. The expression of the Tec2 gene apparently uses a programmed +1 frameshift. To test this hypothesis, we first examined whether this gene has evolved under purifying selection in Tec1 and Tec2. Each element carries three genes, and each has evolved under purifying selection for the function of its encoded protein, as evidenced by a dearth of nonsynonymous changes. This distortion of divergence is apparent in codons both 5′ and 3′ of the frameshift site. Thus, Tec2 transposons have diverged from each other while using a programmed +1 frameshift to produce recombinase, the function of which is under purifying selection. What might this function be? Tyrosine-type site-specific recombinases are extremely rare in eukaryotes, and Tec elements are the first known eukaryotic type II transposons to encode a site-specific recombinase. Tec elements also encode a widespread transposase. The Tec recombinase might function in transposition, resolve products of transposition (bacterial replicative transposons use recombinase or resolvase to separate joined replicons), or provide a function that benefits the ciliate host. Transposons in ciliated protozoa are removed from the macronucleus, and it has been proposed that the transposons provide this “excisase” activity.
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Nugraha, Ary Akbar. "PEMANFAATAN ENERGI PANAS MATAHARI PADA BATU ANDESIT TERHADAP THERMOELECTRIC COOLER TIPE 12706." Risenologi 1, no. 2 (October 7, 2016): 75–82. http://dx.doi.org/10.47028/j.risenologi.2016.12.29.
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Thermoelectric cooler (TEC) merupakan komponen penghasil listrik alternatif yang erat kaitannya dengan pemanfaatan panas atau kalor untuk menghasilkan energi listrik. Modul TEC memanfaatkan perbedaan suhu untuk menghasilkan energi listrik. Penelitian ini bertujuan untuk mengetahui potensi pemanfaatan energi panas matahari pada batu andesit terhadap thermoelectric cooler tipe 12706 sebagai alternatif penghasil energi listrik tenaga surya. Metode penelitian yang digunakan adalah metode eksperimen laboratorium. Pegujian ini dilakukan untuk mengetahui nilai arus dan tegangan yang dihasilkan TEC1-12706. Hasil penelitian ini menunjukkan bahwa media batu andesit dapat dimanfaatkan sebagai media untuk menyimpan panas, sehingga TEC dapat dibangkitkan menghasilkan listrik. Data yang peneliti peroleh ialah terdapat 3 hasil pengujian yaitu, pegujian TEC tanpa beban, pegujian TEC dengan beban resistor 100 ohm dan pengujian TEC dengan beban 250 ohm. Dari ketiga data pengujian tersebut bahwa perbedaan suhu dan tegangan yang dihasilkan TEC lebih optimal pada pengujian TEC tanpa beban yaitu menghasilkan tegangan sebesar 175 mV dan perbedaan suhu 8,1 °C selama penyinaran 30 menit.
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Ahuja, Rohit, Vineeta Nikhil, Anita Pandey, and Priyanka Chaturvedi. "Polymicrobial biofilm disinfection in maxillary and mandibular molars with varying access designs: A microbiological study." Endodontology 35, no. 4 (2023): 360–65. http://dx.doi.org/10.4103/endo.endo_67_23.
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ABSTRACT Aim: The aim of the study is to evaluate and compare the effect of access cavity designs on the polymicrobial biofilm disinfection of root canal system. Methods: One hundred and twenty molar teeth were selected and randomly divided into four groups (n = 30) on the basis of access cavity design: traditional access cavity (TEC), contracted access cavity (CAC), truss access cavity (TAC), and caries-driven access cavity (CDAC). After access preparation, the samples were contaminated for 2 weeks to grow polymicrobial mature biofilm. Microbial sampling from the root canals was performed with sterile paper points before and after instrumentation to determine the bacterial load. The bacterial reduction was counted as CFU/ml and analyzed statistically. Results: Both maxillary and mandibular molars with different cavity designs showed significant decreased in the number of Enterococcus faecalis, Staphylococcus aureus, and Candida albicans postinstrumentation. TEC group showed significantly higher microbial reduction for all tested microorganisms than TAC and CDAC groups (P < 0.05). However, insignificant difference (P > 0.05) was observed between TEC and CAC and TAC and CDAC. Conclusion: In both maxillary and mandibular molars, complete elimination of microbes (E. faecalis, C. albicans, and S. aureus) could not be achieved with any access cavity design. Highest microbial reduction was achieved with TEC and lowest in CDAC. Both TEC and CAC resulted in equal microbial reduction and were superior to TAC and CDAC.
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Panz, Karolina, and Małgorzata Melchior. "Nechama Tec." Zagłada Żydów. Studia i Materiały, no. 19 (December 23, 2023): 751–54. http://dx.doi.org/10.32927/zzsim.1013.
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Nechama Tec urodziła się w 1931 r. w rodzinie Bawników, od kilku pokoleń mieszkającej w Lublinie. Ojciec Roman miał dwie nieduże fabryki, matka Estera zajmowała się domem. Nechamę już w dzieciństwie interesowali inni ludzie. Do- pytywała dlaczego, co i w jaki sposób robili. Jej ojciec uważał, że dzieci powinny wiedzieć jak najwięcej, również o coraz bardziej opresyjnej, wojennej rzeczy- wistości. Zdaniem Tec, to właśnie uratowało ją i jej siostrę, kiedy jako katoliczki w kolejnych domach ukrywały się z rodzicami lub od nich oddzielone. Cała czte- roosobowa rodzina Bawników przeżyła. W 1950 r. Nechama poślubiła Leona Teca, psychiatrę dziecięcego, a dwa lata później małżonkowie wyemigrowali do USA; tam urodziło się dwoje ich dzieci ...
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McCalmont, Timothy H. "TEC." Journal of Cutaneous Pathology 40, no. 9 (August 21, 2013): 785–87. http://dx.doi.org/10.1111/cup.12207.
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Mameekul, Archusuek, Athorn Vora-ud, Surasak Ruamruk, Wanatchaporn Namhongsa, Panida Pilasuta, Kunchit Singsoog, Somporn Thaowankaew, and Tosawat Seetawan. "DESIGN AND FABRICATION OF THERMOELECTRIC SOLID-STATE AIR CONDITIONER." Suranaree Journal of Science and Technology 30, no. 5 (December 14, 2023): 030146(1–5). http://dx.doi.org/10.55766/sujst-2023-05-e02930.
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In this study, we designed and fabricated of thermoelectric solid-state air conditioner (TESSAC) within 400 BTU/hour by using a thermoelectric cooling (TEC) module (model: TEC1-12710) for 3 modules. Thermal management was carried out with the aluminum water-to-radiator system through the liquid moly coolant for controlling the temperature on the hot side of the TEC module. The cooling performance and electrical power were measured during the operating system as performed in one cubic meter for 3 h. According to the experimental results, the TEC1-12710 of one module could be generated cooling by decreasing the temperature to -8.5oC. After useful TEC of 3 modules as useful TESSAC fabrication, TESSAC could be cooled at the cold side around 9.3°C, then the temperature at the center simulation room is around 27.5°C within the ambient temperature of 33.5°C. The coefficient of performance (COP) of TESSAC was calculated to be obtained around 5.5 with the AC power used of 202.31 W.
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Kadouri, Noam, Shir Nevo, Yael Goldfarb, and Jakub Abramson. "Thymic epithelial cell heterogeneity: TEC by TEC." Nature Reviews Immunology 20, no. 4 (December 5, 2019): 239–53. http://dx.doi.org/10.1038/s41577-019-0238-0.
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van de Donk, Niels W. C. J., Philippe Moreau, Michel Delforge, Hermann Einsele, Francesca Ghilotti, Joris Diels, Ahmed Elsada, et al. "Comparative efficacy of teclistamab (tec) versus current treatments (tx) in real-world clinical practice in the prospective LocoMMotion study in patients (pts) with triple-class exposed (TCE) relapsed/refractory multiple myeloma (RRMM)." Journal of Clinical Oncology 40, no. 16_suppl (June 1, 2022): 8016. http://dx.doi.org/10.1200/jco.2022.40.16_suppl.8016.
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8016 Background : Pts with TCE RRMM who have been exposed to ≥3 lines of therapy (LOT) have a poor prognosis and limited tx options. Tec is a B-cell maturation antigen × CD3 bispecific antibody being evaluated in MajesTEC-1 (NCT04557098), a single-arm, phase 1/2 study in pts with RRMM who were TCE to an immunomodulatory drug, a proteasome inhibitor, and an anti-CD38 antibody and received ≥3 LOT. Since MajesTEC-1 lacks a control arm, we assessed the comparative efficacy of tec vs tx currently used in real-world clinical practice (RWCP) by creating an external real-world control arm from LocoMMotion (NCT04035226), a prospective study of RWCP efficacy and safety outcomes in pts with TCE RRMM who received ≥3 LOT. Methods: An external control arm for MajesTEC-1 was created from pts in LocoMMotion (248 pts, clinical cutoff May 21, 2021) who met MajesTEC-1 eligibility criteria. Individual pt-level data from MajesTEC-1 were included from 150 pts treated with tec (1.5 mg/kg weekly) at a clinical cutoff of Sep 7, 2021. Inverse probability of tx weighting with average tx effect on the treated was used to adjust for imbalances in baseline covariates of prognostic significance (refractory status, International Staging System stage, time to progression on prior LOT, extramedullary disease, number of prior LOT, time since diagnosis, average duration of prior LOT, age, hemoglobin, lactate dehydrogenase, creatinine clearance, Eastern Cooperative Oncology Group performance status, gender, type of MM, and prior transplant). Comparative efficacy of tec vs RWCP was estimated for overall response rate (ORR), very good partial response (VGPR) rate, complete response or better (≥CR) rate, duration of response (DOR), progression-free survival (PFS), and overall survival (OS). For binary endpoints (ORR, VGPR rate, and ≥CR rate), relative effect of tec vs RWCP was estimated with an odds ratio, transformed into a response-rate ratio (RR) and 95% confidence interval (CI), derived from weighted logistic regression. A weighted Cox proportional hazards model was used to compute hazard ratios (HRs) and 95% CIs for time-to-event endpoints (DOR, PFS, and OS). Results: Baseline characteristics were well balanced between the 2 cohorts after reweighting the external RWCP cohort. Pts treated with tec had improved outcomes vs tx used in RWCP: ORR (RR 2.31; 95% CI 1.75–2.87; P< 0.0001), VGPR rate (RR 5.54; 95% CI 3.38–7.70; P< 0.0001), ≥CR rate (RR 91.50; 95% CI 12.66–661.43; P< 0.0001), DOR (HR 0.17; 95% CI 0.08–0.36; P< 0.0001), PFS (HR 0.47; 95% CI 0.34–0.67; P< 0.0001), and OS (HR 0.69; 95% CI 0.46–1.05; P= 0.08). Conclusions : Tec showed significantly improved efficacy over RWCP for almost all outcomes, highlighting its potential as a highly effective tx option for pts with TCE RRMM who have been exposed to ≥3 LOT.
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Todorovic-Drakul, M., V. M. Cadez, J. Bajcetic, L. C. Popovic, D. Blagojevic, and A. Nina. "Behaviour of electron content in the ionospheric D-region during solar X-ray flares." Serbian Astronomical Journal, no. 193 (2016): 11–18. http://dx.doi.org/10.2298/saj160404006t.
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One of the most important parameters in ionospheric plasma research, also having a wide practical application in wireless satellite telecommunications, is the total electron content (TEC) representing the columnal electron number density. The F-region with high electron density provides the biggest contribution to TEC while the relatively weakly ionized plasma of the D-region (60 km { 90 km above Earth's surface) is often considered as a negligible cause of satellite signal disturbances. However, sudden intensive ionization processes, like those induced by solar X-ray flares, can cause relative increases of electron density that are significantly larger in the D-region than in regions at higher altitudes. Therefore, one cannot exclude a priori the D-region from investigations of ionospheric influences on propagation of electromagnetic signals emitted by satellites. We discuss here this problem which has not been sufficiently treated in literature so far. The obtained results are based on data collected from the D-region monitoring by very low frequency radio waves and on vertical TEC calculations from the Global Navigation Satellite System (GNSS) signal analyses, and they show noticeable variations in the D-region's electron content (TECD) during activity of a solar X-ray ?are (it rises by a factor of 136 in the considered case) when TECD contribution to TEC can reach several percent and which cannot be neglected in practical applications like global positioning procedures by satellites.
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Fiore, Michele, Gour Chand Daskhan, Baptiste Thomas, and Olivier Renaudet. "Orthogonal dual thiol–chloroacetyl and thiol–ene couplings for the sequential one-pot assembly of heteroglycoclusters." Beilstein Journal of Organic Chemistry 10 (July 8, 2014): 1557–63. http://dx.doi.org/10.3762/bjoc.10.160.
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We describe the first one-pot orthogonal strategy to prepare well-defined cyclopeptide-based heteroglycoclusters (hGCs) from glycosyl thiols. Both thiol–chloroactetyl coupling (TCC) and thiol–ene coupling (TEC) have been used to decorate cyclopeptides regioselectively with diverse combination of sugars. We demonstrate that the reaction sequence starting with TCC can be performed one-pot whereas the reverse sequence requires a purification step after the TEC reaction. The versatility of this orthogonal strategy has been demonstrated through the synthesis of diverse hGCs displaying alternating binary combinations of α-D-Man or β-D-GlcNAc, thus providing rapid access to attractive heteroglycosylated platforms for diverse biological applications.
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Inyurt, S., C. Mekik, and O. Yildirim. "MONITORING IONOSPHERIC VARIATION FOR A DEFINITE PERIOD TIME IN TURKEY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-1-W5 (December 11, 2015): 339–42. http://dx.doi.org/10.5194/isprsarchives-xl-1-w5-339-2015.
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Ionosphere has been studied by a number of scientists in recent years. Since GPS observations cannot provide TEC value directly, it can be estimated from combination of observations. In this study TEC values derived from GPS observations were produced variations with two hours increments from the eighth day to fifteenth day in months just after beginning of each season, namely January, April, July and October in 2014 for ZONG TUSAGA-Aktif station and 41 other stations (TUSAGA-Aktif, EUREF, IGS). TEC values computed by the Bernese 5.0 software were compared with the Global Ionosphere Model (GIM) TEC values regularly published by Center for Orbit Determination in Europe (CODE) and International Reference Ionosphere (IRI-2012) TEC values. As a result of this study, with the comparison of GPS TEC values to GIM TEC values, it has become obvious that GPS TEC values are quite similar to the GIM TEC values. The differences of TEC values derived from GPS TEC and GIM TEC change from 0.91 TECU (January) to 1.88 TECU (October). On the other hand, GPS TEC values are also compared with IRI TEC values, and found out that there is a considerable difference between the two TEC values ranging from 6.30 TECU (January) to 15.15 TECU (April). Moreover, TEC values derived from GPS measurements are attained similar to GIM TEC, but found to stray from IRI-2012 TEC values remarkably.
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Andima, Geoffrey, Emirant B. Amabayo, Edward Jurua, and Pierre J. Cilliers. "Modeling of GPS total electron content over the African low-latitude region using empirical orthogonal functions." Annales Geophysicae 37, no. 1 (January 30, 2019): 65–76. http://dx.doi.org/10.5194/angeo-37-65-2019.
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Abstract. In this paper, an empirical total electron content (TEC) model and trends in the TEC over the African low-latitude region are presented. GPS-derived TEC data from Malindi, Kenya (geographic coordinates 40.194∘ E, 2.996∘ S), and global ionospheric maps (GIMs) were used. We employed an empirical orthogonal function (EOF) analysis method together with least-squares regression to model the TEC. The EOF-based TEC model was validated through comparisons with GIMs, the GPS-derived TEC and the TEC derived from the International Reference Ionosphere 2016 (IRI-2016) model for selected quiet and storm conditions. The single-station EOF-based TEC model over Malindi satisfactorily reproduced the known diurnal, semiannual and annual variations in the TEC. Comparison of the EOF-based TEC model results with the TEC derived from the IRI-2016 model showed that the EOF-based model predicted the TEC over Malindi with fewer errors than the IRI-2016. For the selected storms, the EOF-based TEC model simulated the storm time TEC response over Malindi better than the IRI-2016. In the case of the regional model, the EOF-based TEC model was able to reproduce the TEC characteristics in the equatorial ionization anomaly region. The EOF-based TEC model was then used as a background for estimating TEC trends. A latitudinal dependence in the trends was observed over the African low-latitude region.
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Odeyemi, Olumide Olayinka, Jacob Adeniyi, Olushola Oladipo, Olayinka Olawepo, Isaac Adimula, and Elijah Oyeyemi. "Morphology of GPS and DPS TEC over an equatorial station: validation of IRI and NeQuick 2 models." Annales Geophysicae 36, no. 5 (October 24, 2018): 1457–69. http://dx.doi.org/10.5194/angeo-36-1457-2018.
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Abstract. We investigated total electron content (TEC) at Ilorin (8.50∘ N 4.65∘ E, dip lat. 2.95) for the year 2010, a year of low solar activity in 2010 with Rz=15.8. The investigation involved the use of TEC derived from GPS, estimated TEC from digisonde portable sounder data (DPS), and the International Reference Ionosphere (IRI) and NeQuick 2 (NeQ) models. During the sunrise period, we found that the rate of increase in DPS TEC, IRI TEC, and NeQ TEC was higher compared with GPS TEC. One reason for this can be attributed to an overestimation of plasmaspheric electron content (PEC) contribution in modeled TEC and DPS TEC. A correction factor around the sunrise, where our finding showed a significant percentage deviation between the modeled TEC and GPS TEC, will correct the differences. Our finding revealed that during the daytime when PEC contribution is known to be absent or insignificant, GPS TEC and DPS TEC in April, September, and December predict TEC very well. The lowest discrepancies were observed in May, June, and July (June solstice) between the observed values and all the model values at all hours. There is an overestimation in DPS TEC that could be due to extrapolation error while integrating from the peak electron density of F2 (NmF2) to around ∼1000 km in the Ne profile. The underestimation observed in NeQ TEC must have come from the inadequate representation of contribution from PEC on the topside of the NeQ model profile, whereas the exaggeration of PEC contribution in IRI TEC amounts to overestimation in GPS TEC. The excess bite-out observed in DPS TEC and modeled TEC indicates over-prediction of the fountain effect in these models. Therefore, the daytime bite-out observed in these models requires a modifier that could moderate the perceived fountain effect morphology in the models accordingly. The daytime DPS TEC performs better than the daytime IRI TEC and NeQ TEC in all the months. However, the dusk period requires attention due to the highest percentage deviation recorded, especially for the models, in March, November, and December. Seasonally, we found that all the TECs maximize and minimize during the March equinox and June solstice, respectively. Therefore, GPS TEC and modeled TEC reveal the semiannual variations in TEC.
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Atallah, Rawan, Yara Shatnawi, Aytaj Mammadzadeh, Shahrukh K. Hashmi, Shabeeha K. Rana, Muhammad Umair Mushtaq, Benlazar Mohamed, et al. "The GLAMM1 Study - Global Access to Myeloma Medications: Potential Barriers to Chimeric Antigen Receptors (CART) and T-Cell-Engaging Bispecific Antibodies (TCE) Globally." Blood 142, Supplement 1 (November 28, 2023): 3327. http://dx.doi.org/10.1182/blood-2023-179050.
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Introduction: Novel B cell maturation antigen (BCMA) directed therapies including chimeric antigen receptor- T (CART) such as idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel) have been approved since 2021. More recently in 2022, the first BCMA-directed T-cell-engager (TCE), teclistamab (tec), was also approved for the treatment of relapsed/ refractory multiple myeloma (RRMM). Unfortunately, limited access to these therapies worldwide appears to be a major challenge. This study aims to gain insight into the variation in access to these therapies, and barriers to access. Methods: This study was an electronic survey of 176 hematologists/oncologists in centers across the globe outside the USA who treat MM and was conducted in collaboration with US Myeloma Innovations Research Collaborative (USMIRC). The survey was distributed from June 18 th 2023, to July 15 th 2023. Sections included demographics of respondents, availability of drugs in the country, and barriers to access. The respondents categorized each medication as “easily accessible”, “moderately accessible,” “not readily accessible” or “no access”. To categorize a country/region as having “adequate access”, the cut-off was 60% of responders affirming easy/moderately easy access. We investigated whether higher healthcare spending in a country is associated with better drug accessibility. Health expenditure (HE) of a country's Gross domestic product (GDP) from the World Bank was utilized to categorize countries into two groups: “High healthcare investing nations” (HHIN), which included countries spending >10% of their GDP on healthcare, while “Low healthcare investing nations” (LHIN) included countries spending <10% on healthcare. An interim analysis is reported. Results: There were 95 (54%) completed responses from 33 countries. Most (51%) were university-based academic centers and only 17% were centers with a dedicated focus in plasma cell disorders. Only 17% reported adequate access to ide-cel and 16% to cilta-cel, while a limited, yet higher number of respondents had adequate access to tec (23%). Refer to Table 1 Access to CART (ide-cel and cilta-cel): Globally, only 3 of the 33 (9%) countries had access to ide-cel, cilta-cel or both (France, Morocco, Saudi-Arabia). All other countries had limited access. When grouped by continent, none of the continents had adequate access to CART. Both HHIN and LHIN countries had limited access to CART. Access to TCE (tec): Seven of the 33 (21%) countries had adequate access to tec (Switzerland, Netherlands, France, Portugal, Czech Republic, Morrocco, Saudi Arabia). All other countries had limited access. When grouped by continent, although Europe had the most access, none of the continents had adequate access to TEC. Both HHIN and LHIN countries had limited access to TCE, although relatively, TEC was more accessible compared to CART. Figure 1 summarizes access to CART and TCE Barriers to access: Other than Europe, the most common barrier for ide-cel, cilta-cel and tec was cited as financial burden for patients. Financial burden for patients as a top barrier for each of the products by continent was as follows: Asia (83%), South America (64%), Africa (71%) Australia (100%), and North America (100%). In Europe, for CART, financial burden remained a top barrier (50%) along with local agency approval (50% for ide-cel, 44% for cilta-cel). In Europe, the most cited barrier for TCE was the financial burden for patients (44%), while (33%) of oncologists reported no barrier to TCE. Reimbursement for CART and TCE in Europe requires phase 3 randomized controlled trial data, which is just emerging since 2022 for CART and relatively increased access may be due to the presence of compassionate use programs. Conclusion : The survey is the first attempt to highlight the significantly limited global access to novel therapies (ide-cel, cilta-cel, and tec) for the treatment of RRMM. All continents including HHIN had limited access to CART and TCE. Noticeably, CART is less accessible than TCE, even though approved earlier. The main barrier to both CART and TCE is reported as financial burden for patients. USMIRC in collaboration with oncologists worldwide, global agencies, governments, regulatory agencies, policymakers and industry partners, is planning to further explore restrictions to access to CART and TCE and strategies to overcome these barriers.
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Ghimire, B. D., N. P. Chapagain, V. Basnet, K. Bhatta, and B. Khadka. "Variation of GPS- Tec Measurements of the Year 2014: A Comparative Study with IRI - 2016 Model." Journal of Nepal Physical Society 6, no. 1 (August 8, 2020): 90–96. http://dx.doi.org/10.3126/jnphyssoc.v6i1.30555.
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Total Electron Content (TEC) measured from Global Positioning System (GPS) receivers at latitude of 29.17°N and longitude of 80.62°E in Bardiya and TEC derived from IRI- 2016 model is compared for the year 2014, which is geo- magnetically active year. To find out the reliability of IRI-2016 model, comparative study of GPS- TEC and IRI- TEC is very helpful for the study of TEC variations. In this work diurnal, day to day, month to month and seasonal variations of GPS- TEC and IRI- TEC are analyzed. The comparative study shows that the highest value of VTEC (53 TECU) is found on the day of 61 and over estimation of IRI-TEC over GPS TEC were found from day 151 to day 258. Similarly, months of March and December are the highest and lowest values of VTEC obtained respectively. For monthly variation, IRI-TEC is followed by the pattern of variation with GPS- TEC, where peak value is found to be around 0800 UT to 1100 UT (0145 LT to 0445 LT). The higher values of both GPS- TEC and IRI TEC have been found in spring season, while the lower values are in winter season in case of IRI TEC and partially in summer (before 1000 UT) and winter (after 10UT) in case of GPS TEC. The maximum difference between the value of IRI modeled TEC and GPS TEC has been found to be around 15 TECU, whereas the minimum value is almost around 1 TECU. The correlation between IRI- 2016 modeled TEC and GPS- TEC has been found to be positive (0.57) showing good matching on variations of GPS TEC and IRI-model results.
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Anwar, Effionora, Delly Ramadon, and Ghina Desviyanti Ardi. "NOVEL TRANSETHOSOME CONTAINING GREEN TEA (CAMELLIA SINENSIS L. KUNTZE) LEAF EXTRACT FOR ENHANCED SKIN DELIVERY OF EPIGALLOCATECHIN GALLATE: FORMULATION AND IN VITRO PENETRATION TEST." International Journal of Applied Pharmaceutics 10, no. 1 (December 20, 2018): 299. http://dx.doi.org/10.22159/ijap.2018.v10s1.66.
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Objective: This study aimed to formulate a transethosome cream (TEC) to increase skin penetration of epigallocatechin gallate (EGCG) in green tealeaf extract and evaluate their physicochemical characteristics and skin penetration capacity.Methods: Transethosomes were prepared through thin-layer hydration method in three formulations (F1−F3) with different Span 80 and ethanol concentrations.Transethosome morphology was characterized using transmission electron microscopy, particle size, polydispersity (PDI), and zeta potential using a particlesize analyzer and entrapment efficiency (EE). Penetration was tested using an in vitro Franz diffusion cell with female Sprague-Dawley rat skin as themembrane.Results: Transethosome F2 containing green tea extract equivalent to 3% EGCG, 4% Lipoid P30, 0.75% Span 80, and 30% ethanol had the bestcharacteristic including spherical shape, smallest particle size (35.35 nm), 0.319 PDI, zeta potential of −29.97±3.05 mV, and highest EE of45.26%±8.15%. TEC permitted greater flux than non-TEC (first phase: 60.56±4.52 vs. 25.69±0.83 μg•cm−2•h−1 and second phase: 23.13±1.38 vs.7.36±1.59 μg•cm−2•h−1).Conclusion: Transethosome can increase the skin penetration of green tea leaf extract.
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KAJIWARA, KANJI. "Basic Concept of IF-TEC." FIBER 56, no. 4 (2000): P.110—P.111. http://dx.doi.org/10.2115/fiber.56.p_110.
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Widianto, Tri Nugroho, and Caesar Mahendra. "Kinerja Susunan dan Jumlah Elemen Peltier pada TEC Alat Transportasi Ikan Segar." Jurnal Pascapanen dan Bioteknologi Kelautan dan Perikanan 14, no. 1 (June 28, 2019): 75. http://dx.doi.org/10.15578/jpbkp.v14i1.567.
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AbstrakKinerja cara penyusunan dan jumlah elemen peltier pada pendingin termoelektrik (TEC) alat transportasi ikan segar telah diuji. TEC alat transportasi ikan segar terdiri dari komponen utama yaitu elemen peltier, heatsink, kipas, bracket alumunium dan heat pipe. Uji kinerja dilakukan terhadap susunan dan jumlah elemen peltier TEC alat transportasi ikan segar dengan variasi dua buah TEC dengan elemen peltier tunggal, dua buah TEC dengan elemen peltier ganda dan empat buah TEC dengan elemen peltier tunggal. Parameter yang diamati meliputi suhu ruang penyimpanan ikan, suhu heatsink dan kebutuhan energi TEC. Pengukuran dilakukan selama 120 menit dengan interval pengukuran setiap 10 menit. Suhu ruang peti penyimpanan ikan dengan dua buah TEC peltier ganda adalah 18,8 °C, dua buah TEC peltier tunggal sebesar 13,5 °C dan empat buah TEC peltier tunggal sebesar 8,5 °C. Kebutuhan energi TEC dengan dua buah elemen ganda sebesar 46 Watt, TEC dengan 2 buah elemen peltier tunggal sebesar 83 Watt, sedangkan pada 4 elemen peltier tunggal 166 Watt. Performance of Arrangement and Number the Peltier Elements on Refrigerated Fish Container TECAbstractPerformance of arrangement and number of peltier elements on the refrigerated fish container TEC (thermoelectric cooler) had been tested. The TEC of refrigerated fish container was composed of peltier elements, a heatsink, a fan, an aluminum bracket, and a heat pipe. The arrangement and number of peltier element variations in each refrigerated container box were two TEC composed of a single peltier element, two TEC composed of dual peltier element and four TEC composed of a single peltier element. Performance test was conducted by measuring temperature of box container, temperature of heatsink, and the energy consumption of TEC. Performance test carried out at every 10 minutes for 120 minutes. Temperature of refrigerated container box composed of two TEC with dual peltier element was 18.8 °C, two TEC with single peltier element was 13.5 °C and four TEC with single peltier element was 8.5 °C. The energy consumption of refrigerated container box of two TEC composed dual peltier element was 46 Watts, two TEC composed of single peltier element was 83 Watts and four TEC composed of single peltier element were 166 Watts.
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Mano, H., Y. Yamashita, K. Sato, Y. Yazaki, and H. Hirai. "Tec protein-tyrosine kinase is involved in interleukin-3 signaling pathway." Blood 85, no. 2 (January 15, 1995): 343–50. http://dx.doi.org/10.1182/blood.v85.2.343.bloodjournal852343.
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Among cytoplasmic protein-tyrosine kinases (PTKs) Tec now forms a novel subfamily with recently identified Tec-related PTKs (Btk and Itk/Tsk). Tec is known to be abundantly expressed in myeloid cells, and multiple forms of Tec protein can be generated via the mechanism of alternative splicing. In this report, we have investigated 5′-terminal diversity of the tec messages to demonstrate a predominant form of the Tec protein in mouse hematopoietic cell lines. Using anti-Tec serum, we could show that stimulation with interleukin-3 (IL-3) can induce tyrosine phosphorylation of Tec both in myeloid and pro-B-cell lines. IL-3 stimulation was also shown to induce kinase activity of Tec. Furthermore, we could demonstrate that Tec is constitutively associated with the Shc protein in vivo. Thus, we conclude that Tec is involved in the signaling pathway of IL-3.
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Mano, H., Y. Yamashita, K. Sato, Y. Yazaki, and H. Hirai. "Tec protein-tyrosine kinase is involved in interleukin-3 signaling pathway." Blood 85, no. 2 (January 15, 1995): 343–50. http://dx.doi.org/10.1182/blood.v85.2.343.343.
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Abstract Among cytoplasmic protein-tyrosine kinases (PTKs) Tec now forms a novel subfamily with recently identified Tec-related PTKs (Btk and Itk/Tsk). Tec is known to be abundantly expressed in myeloid cells, and multiple forms of Tec protein can be generated via the mechanism of alternative splicing. In this report, we have investigated 5′-terminal diversity of the tec messages to demonstrate a predominant form of the Tec protein in mouse hematopoietic cell lines. Using anti-Tec serum, we could show that stimulation with interleukin-3 (IL-3) can induce tyrosine phosphorylation of Tec both in myeloid and pro-B-cell lines. IL-3 stimulation was also shown to induce kinase activity of Tec. Furthermore, we could demonstrate that Tec is constitutively associated with the Shc protein in vivo. Thus, we conclude that Tec is involved in the signaling pathway of IL-3.
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Yang, Wen-Chin, Yves Collette, Jacques A. Nunès, and Daniel Olive. "Tec Kinases." Immunity 12, no. 4 (April 2000): 373–82. http://dx.doi.org/10.1016/s1074-7613(00)80189-2.
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Atkinson, Ben T., Wilfried Ellmeier, and Steve P. Watson. "Tec regulates platelet activation by GPVI in the absence of Btk." Blood 102, no. 10 (November 15, 2003): 3592–99. http://dx.doi.org/10.1182/blood-2003-04-1142.
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AbstractThe Tec family kinase Btk plays an important role in the regulation of phospholipase Cγ2 (PLCγ2) downstream of the collagen receptor glycoprotein VI (GPVI) in human platelets. Platelets also express a second member of this family, Tec; however, its function has not been analyzed. To address the role of Tec, we analyzed Btk-/-, Tec-/-, and Btk/Tec double-deficient (Btk-/-/Tec-/-) platelets. Tec-/- platelets exhibit a minor reduction in aggregation to threshold concentrations of collagen or the GPVI-specific agonist collagen-related peptide (CRP), whereas responses to higher concentrations are normal. Tyrosine phosphorylation of PLCγ2 by collagen and CRP is not altered in Tec-/- platelets. However, Btk-/-/Tec-/- platelets exhibit a greater reduction in PLCγ2 phosphorylation than is seen in the absence of Btk, thus revealing an important role for Tec in this situation. Furthermore, Btk-/-/Tec-/- platelets fail to undergo an increase in Ca2+, aggregation, secretion, and spreading in response to collagen or CRP, whereas they aggregate normally to adenosine diphosphate (ADP) and spread on fibrinogen. A residual GPVI signal exists in the Btk-/-/Tec-/- platelets as CRP synergizes with ADP to mediate aggregation. These results demonstrate an essential requirement for Tec and Btk in platelet activation by GPVI and reveal a functional role for Tec in the regulation of PLCγ2 in the absence of Btk. (Blood. 2003;102: 3592-3599)
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Guo, Dongcai, Qiang Sheng, Yu Guo, Jing Xue, and Ze Wang. "Modular integrated thermal control system in scientific experimental express rack on space station." MATEC Web of Conferences 309 (2020): 04013. http://dx.doi.org/10.1051/matecconf/202030904013.
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As an important mission of space stations, space science experiment usually requires effective temperature control measures. Scientific experimental express rack (ER) is a general design for space science experiment. In some space scientific experiments, the temperature of local target element or surrounding exceed heat sink temperature range, effective heating and cooling measures are required. Thermoelectric cooler (TEC) has high reliability and low complexity, which is applicable for temperature control in low gravity conditions. In the ER, the entire surrounding is indirectly heated or cooled by the ambient air, local target element surface is heated or cooled by liquid, TEC is thermal competent for ER thermal control attributed to the low complexity and high reliability, which can enlarge the temperature range of air and liquid. In this paper, a modular integrated thermal control system (MITCS) is designed for a specific ER, which has liquid assembly (LA), TEC assembly (TECA), heat exchanger assembly (HXA) and air cycle assembly (ACA) to provide target surface cooling and heating, entire surrounding cooling and heating. The thermal performance of MITCS using TEC are analyzed, providing guides for the design of the scientific experimental ER and other thermal systems.
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Ma, Guanyi, Jiangtao Fan, Qingtao Wan, and Jinghua Li. "Error Characteristics of GNSS Derived TEC." Atmosphere 13, no. 2 (January 30, 2022): 237. http://dx.doi.org/10.3390/atmos13020237.
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The Global Navigation Satellite System (GNSS) allows for the cost-effective estimation of the ionospheric total electron content (TEC). However, research on error characteristics of the derived TEC is scarce, which provides insights into the quality of the GNSS ionospheric observation. We investigate characteristics of errors in the derived TEC with data from ~260 GNSS dual-frequency receivers of the Crustal Movement Observation Network of China (CMONOC). The slant TEC is calculated from carrier phase measurements and the vertical TEC over China is fitted with a spatial resolution of 1° by 1° in latitude and longitude in four seasons of 2014. It is found that the errors of both the slant TEC and the derived TEC follow Laplace distribution rather than Gaussian distribution in all seasons. The errors of the slant TEC have sharper peaks than those of the derived TEC. The Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) of the slant TEC are typically 0.04 TECU and 0.2 TECU, while the MAE and RMSE of the fitting residuals for the derived TEC are typically 1 TECU and under 2 TECU, respectively. Both MAEs and RMSEs of the derived TEC have the largest value in spring and the smallest value in summer, while the seasonal dependence is only observed in RMSE of the slant TEC.
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Tsugawa, Takuya, Michi Nishioka, Mamoru Ishii, Kornyanat Hozumi, Susumu Saito, Atsuki Shinbori, Yuichi Otsuka, et al. "Total Electron Content Observations by Dense Regional and Worldwide International Networks of GNSS." Journal of Disaster Research 13, no. 3 (June 1, 2018): 535–45. http://dx.doi.org/10.20965/jdr.2018.p0535.
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Two-dimensional ionospheric total electron content (TEC) maps have been derived from ground-based Global Navigation Satellite System (GNSS) receiver networks and applied to studies of various ionospheric disturbances since the mid-1990s. For the purpose of monitoring and researching ionospheric conditions and ionospheric space weather phenomena, we have developed TEC maps of areas over Japan using the dense GNSS network, GNSS Earth Observation NETwork (GEONET), which consists of about 1300 stations and is operated by the Geospatial Information Authority of Japan (GSI). Currently, we are providing high-resolution, two-dimensional maps of absolute TEC, detrended TEC, rate of TEC change index (ROTI), and loss-of-lock on GPS signal over Japan on a real-time basis. Such high-resolution TEC maps using dense GNSS receiver networks are one of the most effective ways to observe, on a scale of several 100 km to 1000 km, ionospheric variations caused by traveling ionospheric disturbances and/or equatorial plasma bubbles, which can degrade single-frequency and differential GNSS positioning/navigation. We have collected all the available GNSS receiver data in the world to expand the TEC observation area. Currently, however, dense GNSS receiver networks are available in only limited areas, such as Japan, North America, and Europe. To expand the two-dimensional TEC observation with high resolution, we have conducted the Dense Regional and Worldwide International GNSS TEC observation (DRAWING-TEC) project, which is engaged in three activities: (1) standardizing GNSS-TEC data, (2) developing a new high-resolution TEC mapping technique, and (3) sharing the standardized TEC data or the information of GNSS receiver network. We have developed a new standardized TEC format, GNSS-TEC EXchange (GTEX), which is included in the Formatted Tables of ITU-R SG 3 Databanks related to Recommendation ITU-R P.311. Sharing the GTEX TEC data would be easier than sharing the GPS/GNSS data among those in the international ionospheric researcher community. The DRAWING-TEC project would promote studies of medium-scale ionospheric variations and their effect on GNSS.
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Chaurasiya, Sunil Kumar, Kalpana Patel, Nabin Sharma, and Abhay Kumar Singh. "Analysis of Total Electron Content (TEC) Variations over Low-Latitude Indian Regions during a Low Sunspot Year of Solar Cycle 24." Journal of Energy Engineering and Thermodynamics, no. 36 (September 18, 2023): 13–21. http://dx.doi.org/10.55529/jeet.13.21.
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The Total Electron Content (TEC) measurements from two stations in the Indian sector, namely the equatorial station Bangalore (Geographic latitude 12°, 58' N, longitude 77°, 35' E) and the equatorial ionization anomaly (EIA) station Varanasi (Geographic latitude 25°, 19' N, longitude 82°, 59' E), are used to examine the variations of the TEC. In comparison to Varanasi, Bangalore has greater daytime TEC values. At the anomalous crest locations, significant daily changes in the TEC values are seen. Three distinct possibilities for the topside electron density present in the model (IRI-2001, IR01-Corr, and Ne-Quick) have been taken into consideration when comparing the observed GPS-TEC with the IRI-2016 model-derived TEC. While the TEC using the IRI01-Corr and IRI-2001 approach exhibits greater variances, the TEC obtained using the Ne-Quick options exhibits better agreement with GPS-TEC.
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Zhao, Guojing, Guobiao Li, Yujia Jiang, Liying Guo, Yangjie Huang, and Zhaoxin Huang. "Teacher Entrepreneurship, Co-Creation Strategy, and Medical Student Entrepreneurship for Sustainability: Evidence from China." Sustainability 14, no. 19 (October 6, 2022): 12711. http://dx.doi.org/10.3390/su141912711.
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The volatile and changing healthcare landscape, heavily influenced by the COVID-19 pandemic and other contemporary crises, poses challenges to the sustainable development of medical education, and integrating innovation and entrepreneurship into medical education is the avenue by which to address the current and future medical challenges. Medical student entrepreneurship education (MSEE) contributes to the individual and social sustainable development of students in terms of their future careers. To investigate the effect of teacher entrepreneurship on MSEE, a hypothesis model of MSEE that includes teachers’ entrepreneurial competence (TEC), teachers’ entrepreneurial behaviors (TEB), and co-creation strategy (CCS) was constructed on the basis of symbolic interactionism. A total of 714 samples were collected from entrepreneurial teachers in Chinese medical universities for quantitative analysis. This study confirmed our hypothesis that TEC and TEB have a positive and statistically significant direct impact on MSEE. As demonstrated in the mediation effect test, when CCS was added as the mediating variable, TEC and TEB had a statistically significant indirect effect on MSEE. With empirical evidence from China, the study provided a new perspective for deepening the research on MSEE and laid the foundation for interdisciplinary research on medical education and entrepreneurship education. The findings contribute to entrepreneurial learning and pedagogical practices in medical education for the sustainable development of medical students.
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Almeida, Milton Luiz de, Luís Sangoi, Itamar Cristiano Nava, Jonantam Galio, Paulo Sérgio Trentin, and Clair Rampazzo. "Crescimento inicial de milho e sua relação com o rendimento de grãos." Ciência Rural 33, no. 2 (April 2003): 189–94. http://dx.doi.org/10.1590/s0103-84782003000200002.
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Este trabalho foi conduzido objetivando identificar características morfo-fisiológicas de milho que se correlacionam com seu crescimento inicial, para determinar sua importância no rendimento de grãos. O experimento foi conduzido no município de Lages, SC, nos anos agrícolas de 1998/99 e 1999/00. Em 1998/99 avaliaram-se os híbridos C901, AS 3601, C 505, AS 3466 e AS 32 e em 1999/00 os híbridos C909, AS 3601, DINA 500, AS 3466 e AS 32. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições. O crescimento inicial foi avaliado através de seis coletas semanais, da emergência até o estádio de dez folhas expandidas. Em cada coleta, determinou-se a área foliar, índice de área foliar (IAF), acúmulo de massa seca, taxa de crescimento celular (TCC) e taxa de expansão celular (TEC). O híbrido AS 3601 apresentou maior área foliar, IAF e TEC do que os demais híbridos em 1998/99. No segundo ano agrícola, o híbrido AS 3466 destacou-se dos demais em acúmulo de massa seca e TCC. Não foram registradas diferenças significativas no rendimento de grãos dos híbridos testados nas duas estações de crescimento. Houve baixa correlação entre os parâmetros de crescimento inicial e o rendimento de grãos da cultura do milho. Já as variáveis utilizadas para estimar o crescimento inicial (MS, área foliar, TEC, IAF e TCC) se correlacionaram positivamente.
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Yasyukevich, Yury, Anna Mylnikova, and Artem Vesnin. "GNSS-Based Non-Negative Absolute Ionosphere Total Electron Content, its Spatial Gradients, Time Derivatives and Differential Code Biases: Bounded-Variable Least-Squares and Taylor Series." Sensors 20, no. 19 (October 7, 2020): 5702. http://dx.doi.org/10.3390/s20195702.
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Global navigation satellite systems (GNSS) allow estimating total electron content (TEC). However, it is still a problem to calculate absolute ionosphere parameters from GNSS data: negative TEC values could appear, and most of existing algorithms does not enable to estimate TEC spatial gradients and TEC time derivatives. We developed an algorithm to recover the absolute non-negative vertical and slant TEC, its derivatives and its gradients, as well as the GNSS equipment differential code biases (DCBs) by using the Taylor series expansion and bounded-variable least-squares. We termed this algorithm TuRBOTEC. Bounded-variable least-squares fitting ensures non-negative values of both slant TEC and vertical TEC. The second order Taylor series expansion could provide a relevant TEC spatial gradients and TEC time derivatives. The technique validation was performed by using independent experimental data over 2014 and the IRI-2012 and IRI-plas models. As a TEC source we used Madrigal maps, CODE (the Center for Orbit Determination in Europe) global ionosphere maps (GIM), the IONOLAB software, and the SEEMALA-TEC software developed by Dr. Seemala. For the Asian mid-latitudes TuRBOTEC results agree with the GIM and IONOLAB data (root-mean-square was < 3 TECU), but they disagree with the SEEMALA-TEC and Madrigal data (root-mean-square was >10 TECU). About 9% of vertical TECs from the TuRBOTEC estimates exceed (by more than 1 TECU) those from the same algorithm but without constraints. The analysis of TEC spatial gradients showed that as far as 10–15° on latitude, TEC estimation error exceeds 10 TECU. Longitudinal gradients produce smaller error for the same distance. Experimental GLObal Navigation Satellite System (GLONASS) DCB from TuRBOTEC and CODE peaked 15 TECU difference, while GPS DCB agrees. Slant TEC series indicate that the TuRBOTEC data for GLONASS are physically more plausible.
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Jimoh, Oluwaseyi, Jiuhou Lei, and Fuqing Huang. "Investigation of Daytime Total Electron Content Enhancements over the Asian-Australian Sector Observed from the Beidou Geostationary Satellite during 2016–2018." Remote Sensing 12, no. 20 (October 16, 2020): 3406. http://dx.doi.org/10.3390/rs12203406.
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This study focused on the investigation of daytime positive ionospheric disturbances and the recurrence of total electron content (TEC) enhancements. TEC data derived from the Beidou geostationary satellite over the Asian-Australian sector were used to study the occurrence of TEC enhancements during 2016–2018. The occurrence of TEC enhancements under quiet geomagnetic condition was analyzed. Furthermore, the occurrence of TEC enhancements during different geomagnetic storm phases was considered to address the question that relates to the recurrence of TEC enhancements during the recovery phase of geomagnetic storms. The seasonal variation of TEC enhancements displayed equinoctial and solstitial peaks at the middle and low latitudes respectively. Besides, there was no evident systematic latitudinal dependence in the occurrence of TEC enhancements, albeit at the equatorial station, nearly no TEC enhancement was observed under Kp < 3. Meanwhile, the occurrences during the main phases of the geomagnetic storms were significantly above the TEC enhancement baselines except at HKWS. The prominence of TEC enhancements during the main phase in comparison with the initial and recovery phases could be attributed to the effects of prompt penetration electric fields and equator-ward neutral winds. Moreover, the pattern of TEC enhancements during the storm recovery indicates the effects of chemical composition changes, winds, and the possible modulation from the lower atmospheric forcing.
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Vaishnav, Rajesh, Erik Schmölter, Christoph Jacobi, Jens Berdermann, and Mihail Codrescu. "Ionospheric response to solar extreme ultraviolet radiation variations: comparison based on CTIPe model simulations and satellite measurements." Annales Geophysicae 39, no. 2 (April 6, 2021): 341–55. http://dx.doi.org/10.5194/angeo-39-341-2021.
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Abstract. The ionospheric total electron content (TEC) provided by the International GNSS Service (IGS) and the TEC simulated by the Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model have been used to investigate the delayed ionospheric response against solar flux and its trend during the years 2011 to 2013. The analysis of the distinct low-latitude and midlatitude TEC response over 15∘ E shows a better correlation of observed TEC and the solar radio flux index F10.7 in the Southern Hemisphere compared to the Northern Hemisphere. Thus, a significant hemispheric asymmetry is observed. The ionospheric delay estimated using model-simulated TEC is in good agreement with the delay estimated for observed TEC against the flux measured by the Solar Dynamics Observatory (SDO) extreme ultraviolet (EUV) Variability Experiment (EVE). The average delay for the observed (modeled) TEC is 17(16) h. The average delay calculated for observed and modeled TEC is 1 and 2 h longer in the Southern Hemisphere compared to the Northern Hemisphere. Furthermore, the observed TEC is compared with the modeled TEC simulated using the SOLAR2000 and EUVAC flux models within CTIPe over northern and southern hemispheric grid points. The analysis suggests that TEC simulated using the SOLAR2000 flux model overestimates the observed TEC, which is not the case when using the EUVAC flux model.
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Ango, Christian Imanuel, Dolfie Paulus Pandara, Ferdy Ferdy, and Seni H. J. Tongkukut. "Investigasi Anomali TEC-Ionosfer Sebelum Letusan Gunung Lokon 14 Juli 2011 Menggunakan Metode Sliding Interquartile." Jurnal MIPA 9, no. 1 (January 24, 2020): 28. http://dx.doi.org/10.35799/jmuo.9.1.2020.27677.
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Gunung Lokon yang berada di Sulawesi Utara adalah salah satu gunung api yang sering mengalami erupsi di Indonesia. Sebelum erupsi terjadi, terdapat aktivitas pra-erupsi yang memicu munculnya anomali Total Electron Content (TEC) di ionosfer. Anomali TEC yang menandai terjadinya letusan diasumsikan sebagai prekursor erupsi yang dapat bermanfaat bagi upaya mitigasi bencana letusan. Tujuan penelitian ini adalah untuk menginvestigasi anomali TEC sebelum letusan gunung Lokon pada tanggal 14 Juli 2011. Investigasi anomali TEC menggunakan metode Sliding Interquartile diperoleh hasil yang menunjukkan adanya anomali TEC yang terjadi 3 hari menjelang letusan yaitu pada tanggal 11 Juli 2011. Hal ini mengindikasikan adanya aktivitas pra-erupsi yang berpengaruh pada kuantitas TEC di ionosfer.Mount Lokon, located in North Sulawesi is among the most active volcanoes in Indonesia. Before the eruption occurred, there was a pre-eruption activity that triggered anomaly on Total Electron Content (TEC) in the ionosphere. TEC anomaly that mark the eruption are assumed as precursors of eruption that can be useful for disaster eruption mitigation efforts. The purpose of this study was to investigate the TEC anomaly before the Lokon eruption on July 14, 2011. Investigation of TEC by using the Sliding Interquartile method, the results showed that an TEC anomaly occurred 3 days before the eruption on July 11, 2011.These indicates the presence of pre-eruptive activity that affects the quantity of TEC in the ionosphere.
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Susaki, Kentaro, Akira Kitanaka, Hiroaki Dobashi, Katsuharu Kittaka, Hiroyuki Mano, Yoshitsugu Kubota, and Terukazu Tanaka. "Tec Kinase Inhibits the Expression of IL-2 Receptor Alpha (CD25) in Human T-Lymphocyte." Blood 112, no. 11 (November 16, 2008): 1545. http://dx.doi.org/10.1182/blood.v112.11.1545.1545.
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Abstract Activation and development of lymphocytes is regulated by the engagement of cell surface immune cell antigen receptors. Following receptor engagement, these receptors transmit signals by the activation of cytoplasmic protein tyrosine kinases (PTKs). The Tec PTK belongs to a group of structurally related nonreceptor PTKs that also includes Btk, Itk (Emt), Rlk (Txk), and Bmx (Etk). We have found the contribution of Tec in the antigen receptor signaling in B-lymphoid cells in the previous studies. Despite the presence of evidences suggesting the involvement of Tec in T-lymphocyte activation pathway via T-cell receptor (TCR) and CD28, the role of Tec in T-lymphocyte still remains unclear because of the lack of apparent defects in T-lymphocyte function in Tec-deficient mice. In this study, we investigated the role of Tec in T-lymphocyte using Jurkat human T-lymphoid cell line stably transfected with a cDNA encoding Tec. We found that the expression of wild type Tec but not kinase-deleted Tec inhibited the expression of IL-2 receptor alpha (CD25) induced by TCR cross-linking. The percentage of CD25 expressing cells after TCR cross-linking was 41.7% in mock-transfected cells, 18.3% in the wild type Tec expressing cells and 41.3% in the kinase-deleted Tec expressing cells. Second, the selective inhibitor of Tec family PTK, LFM-A13, rescued the suppression of TCR-induced CD25 expression observed in the wild type Tec-expressing Jurkat cells. We conclude that Tec PTK mediates signals that negatively regulate CD25 expression induced by TCR cross-linking, implying that this PTK plays a role in the attenuation of the IL-2 activity in human T-lymphocytes.
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Dashora, N., and R. Pandey. "Observations in equatorial anomaly region of total electron content enhancements and depletions." Annales Geophysicae 23, no. 7 (October 14, 2005): 2449–56. http://dx.doi.org/10.5194/angeo-23-2449-2005.
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Abstract. A GSV 4004A GPS receiver has been operational near the crest of the equatorial anomaly at Udaipur, India for some time now. The receiver provides the line-of-sight total electron content (TEC), the phase and amplitude scintillation index, σφ and S4, respectively. This paper presents the first results on the nighttime TEC depletions associated with the equatorial spread F in the Indian zone. The TEC depletions are found to be very well correlated with the increased S4 index. A new feature of low-latitude TEC is also reported, concerning the observation of isolated and localized TEC enhancements in the nighttime low-latitude ionosphere. The TEC enhancements are not correlated with the S4 index. The TEC enhancements have also been observed along with the TEC depletions. The TEC enhancements have been interpreted as the manifestation of the plasma density enhancements reported by Le et al. (2003). Keywords. Ionosphere (Equatorial ionosphere; Ionospheric irregularities)
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Zhang, Wen, Xingliang Huo, Yunbin Yuan, Zishen Li, and Ningbo Wang. "Algorithm Research Using GNSS-TEC Data to Calibrate TEC Calculated by the IRI-2016 Model over China." Remote Sensing 13, no. 19 (October 6, 2021): 4002. http://dx.doi.org/10.3390/rs13194002.
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The International Reference Ionosphere (IRI) is an empirical model widely used to describe ionospheric characteristics. In the previous research, high-precision total ionospheric electron content (TEC) data derived from global navigation satellite system (GNSS) data were used to adjust the ionospheric global index IG12 used as a driving parameter in the standard IRI model; thus, the errors between IRI-TEC and GNSS-TEC were minimized, and IRI-TEC was calibrated by modifying IRI with the updated IG12 index (IG-up). This paper investigates various interpolation strategies for IG-up values calculated from GNSS reference stations and the calibrated TEC accuracy achieved using the modified IRI-2016 model with the interpolated IG-up values as driving parameters. Experimental results from 2015 and 2019 show that interpolating IG-up with a 2.5° × 5° spatial grid and a 1-h time resolution drives IRI-2016 to generate ionospheric TEC values consistent with GNSS-TEC. For 2015 and 2019, the mean absolute error (MAE) of the modified IRI-TEC is improved by 78.57% and 77.42%, respectively, and the root mean square error (RMSE) is improved by 78.79% and 77.14%, respectively. The corresponding correlations of the linear regression between GNSS-TEC and the modified IRI-TEC are 0.986 and 0.966, more than 0.2 higher than with the standard IRI-TEC.
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Yu, Shiguang, Gordon C. Sharp, and Helen Braley-Mullen. "CD8+ T cells induce severe thyroid epithelial cell hyperplasia (TEC H/P) and fibrosis (137.10)." Journal of Immunology 182, no. 1_Supplement (April 1, 2009): 137.10. http://dx.doi.org/10.4049/jimmunol.182.supp.137.10.
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Abstract IFN-γ -/-NOD.H-2h4 mice develop TEC H/P and fibrosis characterized by abnormal proliferation of thyrocytes and infiltration of thyroids by CD4+ and CD8+ T cells. Mice with severe TEC H/P produce anti-mouse thyroglobulin (MTg) autoantibodies, and their splenocytes transfer severe TEC H/P to SCID recipients, indicating that TEC H/P has an autoimmune basis. The goal of this study was to determine what cells transfer severe TEC H/P and fibrosis. Splenocytes from donors with severe TEC H/P cultured 72 hr with MTg consistently transferred more severe TEC H/P than the same number of freshly isolated cells, indicating that cells able to transfer severe TEC H/P can be activated in vitro. To determine what cells are important for transfer of TEC H/P, spleens of IFN-γ -/- mice with severe TEC H/P were activated in vitro, and CD4+ and CD8+ T cells were isolated and transferred to SCID recipients. Recipients of CD8+ cells had more severe TEC H/P and more fibrosis than recipients of CD4+ T cells or unseparated splenocytes. They had few infiltrating CD4+ cells, suggesting that CD8+ T cells are primary effector cells for severe TEC H/P and fibrosis. Recipients of CD4+ T cells developed mild hyperplasia and minimal fibrosis. Studies are in progress to determine what molecules secreted by CD8+ T cells mediate TEC H/P and fibrosis, and if CD4+ T cells are required for activation of CD8+ T cells. (Supported by VA Merit Review and NIH R56 AI074857).
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Shimhanda, S., S. Francis, and P. J. Cilliers. "Analysis of ionospheric Total Electron Content variability determined from Global Navigation Satellite System data." Namibian Journal for Research, Science and Technology 1, no. 1 (October 16, 2020): 3–9. http://dx.doi.org/10.54421/njrst.v1i1.4.
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Free electrons refract signals transmitted from satellites mainly during their trans-ionospheric propagation. The side-effect is the measured path length travelled by a signal is about five to fifteen meters longer than the actual path covered. Moreover, magnitudes of signal delays are directly proportional to the Total Electron Content (TEC). TEC is an ionospheric parameter indicating the total amount of electrons along a signal path between satellites and ground based receivers. This study was conducted because the TEC-induced ionospheric delay is themain error source in single frequency receivers. Hence, this study involved the extraction of TEC values from GNSS data with the Global Positioning System (GPS) TEC software to observe diurnal and seasonal variations of GNSS-TEC. Additionally, the study compared TEC plots of Windhoek(22.5741⁰S; 17.0894⁰E), Hermanus(South Africa, -34.42463056⁰S; 19.22306111⁰E), and Dakar(Senegal, 14.720903⁰N; -17.439503⁰W) to validate whether the ionospheric delay varies in accordance with the geographic location or not.Comparisons of observational GNSS-TEC and IRI-TEC derived from the IRI model were made to determine the accuracy of the IRI-model in the southern hemisphere. GNSS data were derived from a dual-frequency receiver installed at Windhoek (22.5741⁰S; 17.0894⁰E), Namibia. Results show that maximum TEC was prevalent in spring while minimum TEC generally occurred throughout winter. Moreover, results revealed that the International Reference Ionosphere (IRI) model overestimated GNSS-TEC in winter but underestimatedduring summer, autumn and spring.
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Sunardi, Bambang, Supriyanto Rohadi, Sulastri Sulastri, and Rahmat Setyo Yuliatmoko. "INKONSISTENSI TEC GIM DARI DATA GNSS SEBAGAI PREKURSOR GEMPABUMI DI WILAYAH MALUKU UTARA TAHUN 2019." Elipsoida : Jurnal Geodesi dan Geomatika 3, no. 02 (December 4, 2020): 157–63. http://dx.doi.org/10.14710/elipsoida.2020.9182.
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Currently, the GNSS has grown rapidly and is widely applied for commercial and research purposes, one of which is an earthquake precursor. Precursor detection of major earthquakes using TEC in the ionosphere has recently become a promising method. This paper focuses on investigating TEC inconsistencies before major earthquakes in the North Maluku region during 2019. Earthquake data refers to the U.S. Geological Survey, while the TEC data comes from GIM which comes from international GNSS. TEC anomaly was observed by applying the TEC correlation method near the epicenter of the earthquake to obtain the TEC inconsistency index. The TEC anomaly classification is decided when the inconsistency index is outside a defined threshold. The Dst index in the same time frame is used to analyze TEC inconsistencies due to geomagnetic storms. The results of research on the January 7, 2019 Mw 6.6 earthquake, the July, 7 2019 Mw 6.9 earthquake, the July 14, 2019 Mw 7.2 earthquake, and the November 14, 2019 Mw7.1 earthquake showed TEC inconsistency 29 to 1 day before the mainshock. Referring to these results, investigations of TEC inconsistencies prior to the major earthquake can be continuously developed until they reach the expected success rate
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Wielgosz, P., L. W. Baran, I. I. Shagimuratov, and M. V. Aleshnikova. "Latitudinal variations of TEC over Europe obtained from GPSobservations." Annales Geophysicae 22, no. 2 (January 1, 2004): 405–15. http://dx.doi.org/10.5194/angeo-22-405-2004.
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Abstract. GPS technique has opened broad possibilities to study the TEC distribution on a regular basis. In this paper, the latitudinal dependence of TEC over Europe for geographic latitudes ranging from 40°N to 75°N is presented. We discuss the day-to-day variations of the latitudinal TEC profiles for a period of 1999 to 2001 for both quiet and disturbed magnetic conditions. More than 4300 TEC profiles were created from the TEC maps with a one-hour interval. GPS data from 65 European permanent stations were used to produce the TEC maps. The comparison of GPS-derived TEC profiles with the IRI model is also discussed. Key words. Ionosphere (mid-latitude ionosphere; ionospheric disturbances)
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Ramarli, Dunia, Maria Teresa Scupoli, Emma Fiorini, Ornella Poffe, Monica Brentegani, Antonello Villa, Germana Cecchini, Giuseppe Tridente, and Pier Carlo Marchisio. "Thymocyte Contact or Monoclonal Antibody-Mediated Clustering of 3β1 or 6β4 Integrins Activate Interleukin-6 (IL-6) Transcription Factors (NF-κB and NF-IL6) and IL-6 Production in Human Thymic Epithelial Cells." Blood 92, no. 10 (November 15, 1998): 3745–55. http://dx.doi.org/10.1182/blood.v92.10.3745.
Full textAbstract:
Abstract T-cell precursors develop within the thymus in contact with multiple supportive elements, among which thymic epithelial cells (TEC) are known to exert a dominant role in their homing, survival, and functional differentiation. All these functions are supported by cell-cell contacts and cytokine release. Signaling events triggered in lymphoid cells by adhesion to TEC are well characterized, but little is known about the opposite phenomenon. To address this issue, we derived cultures of TEC from human normal thymus. TEC monolayers were cocultured with thymocytes and immunostained with monoclonal antibodies (MoAbs) to integrin (2, 3, 4, and 6) and β (β1 and β4) chains. Optical and confocal analysis showed that integrins were polarized on TEC at discrete surface locations: 6β4 lined the basal surface of TEC monolayers, whereas 3β1 was found mostly at TEC-TEC contacts; it is noteworthy that both 3β1 and 6β4 became highly enriched also at the boundaries with adherent thymocytes. Functional studies performed with MoAbs anti-β1 and -β4 integrins showed that β1, and, to a much lower extent, β4 heterodimers are involved in the TEC-thymocyte adhesion. Thymocyte contact or MoAb-mediated ligation of 3, 6, β1, and β4 integrins was investigated as a potential inducer of intracellular signaling in TEC. Thymocyte adhesion or cross-linking of MoAbs bound to integrins clustered at the TEC/thymocyte contact sites led to activation of interleukin-6 (IL-6) gene transcription factors, namely NF-IL6 serine phosphorylation and NF-κB nuclear targeting, as well as to increased IL-6 secretion. We propose that integrin clustering occurring during TEC-thymocyte contacts modulates in TEC the gene expression of a cytokine involved in thymocyte growth and functional differentiation.
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Ramarli, Dunia, Maria Teresa Scupoli, Emma Fiorini, Ornella Poffe, Monica Brentegani, Antonello Villa, Germana Cecchini, Giuseppe Tridente, and Pier Carlo Marchisio. "Thymocyte Contact or Monoclonal Antibody-Mediated Clustering of 3β1 or 6β4 Integrins Activate Interleukin-6 (IL-6) Transcription Factors (NF-κB and NF-IL6) and IL-6 Production in Human Thymic Epithelial Cells." Blood 92, no. 10 (November 15, 1998): 3745–55. http://dx.doi.org/10.1182/blood.v92.10.3745.422a25_3745_3755.
Full textAbstract:
T-cell precursors develop within the thymus in contact with multiple supportive elements, among which thymic epithelial cells (TEC) are known to exert a dominant role in their homing, survival, and functional differentiation. All these functions are supported by cell-cell contacts and cytokine release. Signaling events triggered in lymphoid cells by adhesion to TEC are well characterized, but little is known about the opposite phenomenon. To address this issue, we derived cultures of TEC from human normal thymus. TEC monolayers were cocultured with thymocytes and immunostained with monoclonal antibodies (MoAbs) to integrin (2, 3, 4, and 6) and β (β1 and β4) chains. Optical and confocal analysis showed that integrins were polarized on TEC at discrete surface locations: 6β4 lined the basal surface of TEC monolayers, whereas 3β1 was found mostly at TEC-TEC contacts; it is noteworthy that both 3β1 and 6β4 became highly enriched also at the boundaries with adherent thymocytes. Functional studies performed with MoAbs anti-β1 and -β4 integrins showed that β1, and, to a much lower extent, β4 heterodimers are involved in the TEC-thymocyte adhesion. Thymocyte contact or MoAb-mediated ligation of 3, 6, β1, and β4 integrins was investigated as a potential inducer of intracellular signaling in TEC. Thymocyte adhesion or cross-linking of MoAbs bound to integrins clustered at the TEC/thymocyte contact sites led to activation of interleukin-6 (IL-6) gene transcription factors, namely NF-IL6 serine phosphorylation and NF-κB nuclear targeting, as well as to increased IL-6 secretion. We propose that integrin clustering occurring during TEC-thymocyte contacts modulates in TEC the gene expression of a cytokine involved in thymocyte growth and functional differentiation.
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Yu, Shiguang, Gordon C. Sharp, and Helen Braley-Mullen. "CD4+ T cells are required for CD8+ T-cell activation but not for CD8+ T cell effector function for induction of thyrocyte hyperplasia (TEC H/P) and fibrosis (93.7)." Journal of Immunology 184, no. 1_Supplement (April 1, 2010): 93.7. http://dx.doi.org/10.4049/jimmunol.184.supp.93.7.
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Abstract IFN-γ-/-NOD.H-2h4 mice develop TEC H/P and fibrosis characterized by abnormal proliferation of thyrocytes and infiltration of thyroids by CD4+ and CD8+ T cells. CD8+ T cells are the primary effector cells for TEC H/P. CD4-/- and CD8-/- IFN-γ-/- NOD.H-2h4 mice were generated to determine if CD4+ T cells were required for activation of CD8+ T cells that induce TEC H/P and fibrosis. 60-70% of IFN-γ-/- mice given NaI water for 6-7 mo develop severe TEC H/P and fibrosis, compared to 11 of 53 (21%) CD4-/- mice and only 2 of 42 (5%) CD8-/- mice. TEC H/P incidence in CD4-/- mice given splenocytes from CD8-/- mice is similar to that of IFN-γ-/- mice (60%). Splenocytes from IFN-γ-/- donors with severe TEC H/P transfer severe TEC H/P to SCID recipients after culture in vitro for 72 hr, and purified CD8+ T cells from the same donors also transfer severe TEC H/P to SCID recipients. Splenocytes from some CD4-/- donors with severe TEC H/P can transfer severe TEC H/P to SCID recipients, but more often they transfer only minimal disease. These results suggest that CD4+ T cells are required for optimal activation of CD8+ T cells that induce TEC H/P, and they may also be important for optimal in vitro activation of CD8+ T cells that induce severe TEC H/P. In contrast, after CD8+ T cells are fully activated, CD4+ T cells are not required for their mobilization to thyroids or for effector function leading to TEC H/P and fibrosis.
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Kane, Lawrence P., and Simon C. Watkins. "Dynamic Regulation of Tec Kinase Localization in Membrane-proximal Vesicles of a T Cell Clone Revealed by Total Internal Reflection Fluorescence and Confocal Microscopy." Journal of Biological Chemistry 280, no. 23 (April 6, 2005): 21949–54. http://dx.doi.org/10.1074/jbc.m412913200.
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Tec family tyrosine kinases are key regulators of lymphocyte activation and effector function. Several Tec family kinases (Tec, Itk, Rlk/Txk) are expressed in T cells, but it is still not clear to what degree these are redundant or have unique functions. We recently demonstrated that Tec alone, among the Tec kinase family members examined, can induce nuclear factor of activated T cell-dependent transcription. This unique functional characteristic correlated with a unique pattern of subcellular localization, as Tec (but not other family members) was found in small vesicles, the appearance of which requires signaling through the T cell receptor for antigen. Here we report on our studies of these Tec-containing structures in live T cells, using total internal reflection fluorescence microscopy. With this technique, we showed that, in live T cells, the Tec vesicles are located at the plasma membrane, the vesicles are unique to Tec (and not the related kinase Itk), and their formation and maintenance require T cell receptor signaling through Src family kinases and PI 3-kinase. Finally, we have imaged isolated T cell membranes by confocal microscopy, confirming the membrane-proximal location of Tec vesicles, as well as demonstrating overlap of these vesicles with the tyrosine kinase Lck, the Tec substrate PLC-γ1, and the early endosomal antigen 1 marker EEA1.
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Zhang, Michael J., Sarah Franklin, Yifeng Li, Sujing Wang, Xiaochen Ru, Scherise A. Mitchell-Jordan, Hiroyuki Mano, Enrico Stefani, Peipei Ping, and Thomas M. Vondriska. "Stress signaling by Tec tyrosine kinase in the ischemic myocardium." American Journal of Physiology-Heart and Circulatory Physiology 299, no. 3 (September 2010): H713—H722. http://dx.doi.org/10.1152/ajpheart.00273.2010.
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Nonreceptor tyrosine kinases have an increasingly appreciated role in cardiac injury and protection. To investigate novel tasks for members of the Tec family of nonreceptor tyrosine kinases in cardiac phenotype, we examined the behavior of the Tec isoform in myocardial ischemic injury. Ischemia-reperfusion, but not cardiac protective agents, induced altered intracellular localization of Tec, highlighting distinct actions of this protein compared with other isoforms, such as Bmx, in the same model. Tec is abundantly expressed in cardiac myocytes and assumes a diffuse intracellular localization under basal conditions but is recruited to striated structures upon various stimuli, including ATP. To characterize Tec signaling targets in vivo, we performed an exhaustive proteomic analysis of Tec-binding partners. These experiments expand the role of the Tec family in the heart, identifying the Tec isoform as an ischemic injury-induced isoform, and map the subproteome of its interactors in isolated cells.
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Mohib, Kanishka, Qiunong Guan, Hong Diao, Caigan Du, and Anthony M. Jevnikar. "Proapoptotic activity of indoleamine 2,3-dioxygenase expressed in renal tubular epithelial cells." American Journal of Physiology-Renal Physiology 293, no. 3 (September 2007): F801—F812. http://dx.doi.org/10.1152/ajprenal.00044.2007.
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Exposure of renal tubular epithelial cells (TEC) to IFN-γ/TNF-α leads to Fas/FasL-mediated self-injury, which contributes to allograft rejection. Indoleamine 2,3-dioxygenase (IDO) converts tryptophan to N-formyl-kynurenine and contributes to immune privilege in tissues by increasing Fas-mediated T cell apoptosis. However, renal expression of IDO and its role in promoting Fas-mediated TEC death have not been examined. IDO expression was analyzed by RT-PCR and Western blot. Apoptosis was measured by fluorescence-activated cell sorting analysis and terminal deoxytransferase-mediated dUTP nick end labeling. We demonstrated that functional IDO is expressed in TEC and is increased by IFN-γ/TNF-α exposure. Increased IDO activity promoted TEC apoptosis, whereas inhibition of IDO by its specific inhibitor 1-methyl-d-tryptophan attenuated IFN-γ/TNF-α-mediated TEC apoptosis and augmented TEC survival. Transgenic expression of IDO resulted in increased TEC apoptosis in the absence of proinflammatory cytokine exposure, supporting a central role for IDO in TEC injury. Inhibition of IDO-mediated TEC death by a caspase-8-specific inhibitor (Z-IETD-FMK), as well as the absence of an IDO effect in Fas-deficient and FasL-deficient TEC, supports a Fas/FasL-dependent, caspase-8-mediated mechanism for IDO-enhanced TEC death. These data suggest that renal IDO expression may be deleterious during renal inflammation, because it enhances TEC self-injury through Fas/FasL interactions. Thus attenuation of IDO may represent a novel strategy to promote kidney function following ischemia and renal allograft rejection.
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Swanbery, Nathan J. "Enforced expression of c-Myc and T58A-mutant c-Myc in adult thymic epithelial cell subsets." Journal of Immunology 210, no. 1_Supplement (May 1, 2023): 172.07. http://dx.doi.org/10.4049/jimmunol.210.supp.172.07.
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Abstract Thymic epithelial cells (TEC) are essential for T lymphopoiesis. Cortical (c)TEC support T lineage commitment and positive selection, whereas medullary (m)TEC delete self-reactive T cells to enforce central tolerance. Both cTEC and mTEC contain several distinct subtypes that were only recently characterized, and precursor-progeny relationships among adult TEC remains incompletely understood. Prior work in our lab demonstrated that enforced expression of c-Myc broadly in TEC under a constitutive FoxN1-Cre increased thymus size and TEC numbers, while maintaining morphology and function. To elucidate which TEC subtypes require enforced c-Myc expression to drive thymic expansion in adults, we’ve developed and acquired Cre-ERT2 systems under the control of TEC-specific genes FoxN1, Aire, and Ccl21a. This allows us to target expression of c-Myc or stabilized T58A-mutant c-Myc to specific subsets of TEC in adult mice. Analysis of these systems is currently ongoing and results will be presented. We hypothesize that enforced expression of c-Myc or stabilized T58A-mutant c-Myc in specific adult TEC subsets will expand the targeted population and may eventually result in transformation. Regardless of whether our hypothesis is correct, our experiments will contribute to better understanding of c-Myc-driven thymic hyperplasia and may provide a mouse model for human thymoma.
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Sugihara, S., H. Fujiwara, H. Niimi, and G. M. Shearer. "Self-thyroid epithelial cell (TEC)-reactive CD8+ T cell lines/clones derived from autoimmune thyroiditis lesions. They recognize self-thyroid antigens directly on TEC to exhibit T helper cell 1-type lymphokine production and cytotoxicity against TEC." Journal of Immunology 155, no. 3 (August 1, 1995): 1619–28. http://dx.doi.org/10.4049/jimmunol.155.3.1619.
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Abstract Self-thyroid epithelial cell (TEC)-reactive CD8+ and CD4+ T cell lines were established by culturing T cells that infiltrate in autoimmune thyroiditis lesions. We investigated the properties of CD8+ T cell lines and clones in comparison with previously characterized CD4+ T cell lines/clones. Although the recognition of self-Ag by anti-TEC CD4+ T cell lines/clones required the cooperation of syngeneic spleen cells as APC, a representative CD8+ line (N4C) was stimulated with syngeneic TEC in the absence of APC. Precise analysis of MHC restriction using N4C-derived clones revealed that CD8+ clones recognize self-Ag on TEC in the context of class I MHC molecules. Most CD8+ clones were also found to express TCR with V beta specificities that were different from those observed for anti-TEC CD4+ clones. N4C cells produced IL-2, IFN-gamma, and TNF-alpha beta, but not IL-4 and IL-5 after stimulation with TEC, thus exhibiting the profile of lymphokine production similar to that expressed by CD4+ Th1 on one hand, but on the other, they showed the functional property that has not been observed for anti-TEC CD4+ clones. Namely, they elicited appreciable levels of cytolytic effects on syngeneic TEC in a short-term (4-h) 51Cr release assay. Thus, these results indicate that self-TEC-reactive CD8+ T cell lines/clones recognize Ag directly on TEC in a class I MHC-restricted way so as to exhibit various functions including the Th1-like profile of lymphokine production and anti-TEC cytolysis. The results are also discussed in terms of the nature of self-Ag presented with class I MHC molecules on TEC, as well as the potential roles of anti-TEC CD8+ T cells in the pathogenesis of thyroiditis.
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Li, Lei, Shu Fang Zhang, Yi Zhuo Wang, and Qing Hu. "Solar Activity Effects on the Variabilities of Long-Term Ionospheric TEC." Advanced Materials Research 850-851 (December 2013): 1331–34. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.1331.
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To reveal the modulating effects of the solar activity on ionospheric TEC, the long-term characteristics of TEC were analyzed. The analysis was based on the data of the sunspot and data of GPS observation provided by IGS analysis centers from 1999 to 2011. The results showed that the variation of monthly mean TEC was of significant regularity. The regularity was caused mainly modulation action of solar activity. In view of the spatial variation of TEC, the monthly mean TEC can be well described for modeling and prediction on base of relationship between TEC and latitude.
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Mol, Isha, Yannan Hu, Thomas W. LeBlanc, Joseph C. Cappelleri, Haitao Chu, Guido Nador, Didem Aydin, Alex Schepart, and Patrick Hlavacek. "A Matching-Adjusted Indirect Comparison of the Efficacy of Elranatamab and Teclistamab in Patients with Triple-Class Exposed/Refractory Multiple Myeloma." Blood 142, Supplement 1 (November 28, 2023): 2015. http://dx.doi.org/10.1182/blood-2023-186409.
Full textAbstract:
BACKGROUND Elranatamab, a novel B-cell maturation antigen (BCMA)- and CD3-directed bispecific antibody, recently demonstrated efficacy and safety in patients with triple-class exposed/refractory multiple myeloma (TCE/R MM) in the phase 2, single-arm MagnetisMM-3 trial (NCT04649359). Teclistamab (TEC) is a BCMA-CD3 directed bispecific antibody which was recently approved in the US for patients with TCE/R MM who received 4+ prior lines of treatment, based on response rates in the MajecTEC-1 trial (NCT04557098). In the absence of comparative trials of elranatamab and TEC, an unanchored matching-adjusted indirect comparison (MAIC) was conducted to assess their relative efficacy. METHODS Individual patient data (IPD) from the 14.7 month follow- up of MagnetisMM-3 Cohort A (BCMA-naïve, N = 123), were reweighted to match published summary data from ~23 month follow-up in MajesTEC-1 (N=165) in Sidana et al (2023). Overall, the inclusion and exclusion criteria of the trials were similar; however, MajesTEC-1 excluded patients with Eastern Cooperative Oncology Group (ECOG) performance status >1; therefore, patients with ECOG 2 in the MagnetisMM-3 trial were removed from the analysis (resulting N=116). To adjust for cross-trial differences, patients from MagnetisMM-3 were reweighted to match the baseline characteristics of the TEC trial patients. Weights were determined using a propensity score-type logistic regression via the method of moments (Signorovitch et al. 2012) based on age, median time since diagnosis, International Staging System disease stage, high-risk cytogenetics, extramedullary disease, number of prior lines of therapy, ECOG performance status, and penta-exposed and penta-refractory status. In the analysis for the overall survival (OS) endpoint, sex was also included. The adjusted variables were obtained based on univariate Cox regressions using the MagnetisMM-3 IPD, a systematic literature review of prognostic variables and effect modifiers in relapsed or refractory MM, a review of the prognostic variables identified in clinical studies for TCE/R MM, and a review of the recent relevant indirect comparisons, and were confirmed by clinical experts. A sensitivity analysis was conducted in which missing values of the adjusted baseline characteristics for elranatamab were imputed by a random sample of the observations in MagnetisMM-3 to potentially increase the effective sample size (ESS). Unanchored MAIC analyses were conducted in R studio following the code provided in the National Institute for Health and Care Excellence (NICE) Decision Support Unit (DSU) 18 by Phillippo et al (2016). The efficacy outcomes included objective response rate (ORR), duration of response (DoR), progression-free survival (PFS), and OS. Kaplan-Meier curves of DoR, PFS, and OS from MajesTEC-1 were digitized according to Guyot et al (2012). Results were reported as rate difference (i.e., the difference between the ORR of elranatamab and TEC) and odds ratios (ORs) for binary endpoints or hazard ratios (HRs) for time-to-event endpoints, with 95% confidence intervals (CIs). RESULTS After adjustment in the MAIC, the selected key baseline characteristics were comparable between elranatamab and TEC. For all endpoints except OS, the post-matching ESS for elranatamab was 75 in the base case and 89 in the sensitivity analysis. For OS, the ESSs were 73 and 87 for the base case and scenario analyses, respectively. Compared with TEC, elranatamab was associated with significantly better ORR (rate difference: 12.30; 95% CI: 0.70-23.90; OR: 1.79; 95% CI: 1.01-3.19) and PFS (HR 0.59; 95% CI 0.39-0.89). Patients treated with elranatamab had numerically better DoR (HR: 0.64; 95% CI: 0.33-1.23) and OS (HR: 0.66; 95% CI: 0.42-1.03) compared to those who received TEC (Table 1 and 2). Results in the sensitivity analysis were consistent with the base case. CONCLUSIONS In this MAIC, elranatamab demonstrated significantly better ORR and PFS than TEC, and numerically better DOR and OS in both the base case and the sensitivity analysis. These results suggest that elranatamab is an effective option for treating patients with TCE/R MM.
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Muthukrishnan, Sree Deepthi, Amy Pham, Alvaro Alvarado, Riki Kawaguchi, and Harley Kornblum. "TMIC-75. TUMOR ENDOTHELIAL CELL-DERIVED ASPORIN DIFFERENTIALLY REGULATES GLIOBLASTOMA GROWTH." Neuro-Oncology 24, Supplement_7 (November 1, 2022): vii288. http://dx.doi.org/10.1093/neuonc/noac209.1118.
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Abstract Gliomas are the most prevalent and malignant brain tumors. A major histopathological feature that distinguishes the high-grade (IV) glioblastoma (GBM) from slow-growing low-grade (II and III) glioma is microvascular hyperproliferation. Although gliomas are highly vascularized tumors, anti-angiogenic therapies have failed to prevent recurrence and significantly improve patient survival. To determine if tumor endothelial cells (TEC) display molecular heterogeneity, we performed bulk RNA-sequencing on cultured CD31+ TEC from low-grade (II/III), and high-grade (IV, primary and recurrent) gliomas. Low- and high-grade TEC exhibited significant molecular heterogeneity, with increased enrichment of extracellular matrix and cell cycle-related gene sets in low-grade and enrichment of cytokine and immune response-related gene sets in high-grade TEC. We also found significant functional differences in proliferation capacity, and resistance to anti-angiogenic therapies between low-and high-grade TEC. Co-transplantation of low-grade TEC with tumor cells significantly inhibited GBM growth and enhanced survival, whereas high-grade TEC promoted growth of tumors in orthotopic xenografts in vivo. Differential gene expression analysis revealed several proteoglycans distinctly expressed by low-grade TEC. Of the highly enriched molecules in low-grade TEC, Asporin (ASPN), a small leucine-rich repeat proteoglycan (SLRP) significantly inhibited growth and proliferation of IDH1-wt GBM cells but did not affect IDH1-mutant tumor cells. Co-transplantation of TEC-lacking ASPN with IDH1-wt GBM partially rescued the growth-inhibitory effect of low-grade TEC on tumor growth and reduced survival. Ongoing experiments are aimed at determining the molecular mechanism underlying the growth-inhibitory effects of TEC-derived Asporin on glioma.