Top PDF Long-term trends of <i>fo</i>F2 independent of geomagnetic activity

Long-term trends of <i>fo</i>F2 independent of geomagnetic activity

Long-term trends of <i>fo</i>F2 independent of geomagnetic activity

The “trend < σ ” situation mentioned above is the second out of the three criteria. The third criterion is that the sign of the r(δf oF2, Ap) for every 30-year interval considered should be the same. If the sign changes during the entire period considered (for example, it is positive for the 1958– 1987, 1959–1988 intervals and is negative for the 1965– 1994, 1966–1995 intervals, or vice versa) the picture is un- stable and the corresponding trend is not accepted and this fact is indicated as “plus/min” in the Comments column. As a rule, the “plus/min” situation is accompanied by invalidat- ing other criteria for accepting k(tr, ave1) for this particular hour (in Table 1 for 00:00 LT all three criteria are not valid). It should be especially emphasized that if one of the above three criterion is not valid, it does not mean that the k(t r, ave1) for this particular LT moment is necessarily close to zero or very small. It merely means that for this particular hour the initial data were not good enough for the method described to be used and so the scatter of the k(tr) obtained is large or the correlation between δfoF2 and Ap is low, the latter fact making it difficult to get rid of the geomagnetic ef- fect. “The data were not good” means that for one or a few years the monthly mean values for this particular LT initially used differ significantly from the values for the other LT.
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An interpretation of the <i>ƒo</i>F2 and <i>hm</i>F2 long-term trends in the framework of the geomagnetic control concept

An interpretation of the <i>ƒo</i>F2 and <i>hm</i>F2 long-term trends in the framework of the geomagnetic control concept

An example of such long-term variations is given in Fig. 9 for a mid-latitude station Slough, where ionospheric ob- servations are available from the early 1930s. Variations of the 11-year Ap index are repeated in Fig. 9 (top) for further discussion. The δfoF2 variations are considered for (M + m) and (m) year selections (Danilov and Mikhailov, 1999; Mikhailov and Marin, 2000). Solid and dashed lines are the least squares fitting by the 4th degree polynomial (a higher degree gives practically the same results). Everywhere er- ror bars present the standard deviation over 12 monthly val- ues. An anti-phase type of δfoF2 and Ap long-term variations is seen for the period in question. The periods of increas- ing geomagnetic activity (before 1955 and after the end of the 1960s) are seen to correspond to negative foF2 trends, while during the decreasing phase of geomagnetic activity (1955 to the end of the 1960s), a small positive foF2 trend takes place. There is also a tendency for the foF2 trend to switch from negative to positive after 1990, in accordance
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Long-term <i>hm</i>F2 trends in the Eurasian longitudinal sector from the ground-based ionosonde observations

Long-term <i>hm</i>F2 trends in the Eurasian longitudinal sector from the ground-based ionosonde observations

to reveal significant trends from the ionosonde observations. An approach being developed by Danilov and Mikhailov (1998, 1999) and Mikhailov and Marin (2000) has allowed us to find systematic variations of the foF2 trend magnitude with geomagnetic (invariant) latitude and local time. The ap- plication of this approach to foF2 trend analysis resulted in a new geomagnetic control concept based on the contemporary understanding of the F2-layer storm mechanisms (Mikhailov and Marin, 2000). Since hmF2 and N mF2 are related by the mechanism of the F2-layer formation, any hypothesis of the F2-layer parameter trends should explain the observed trends of both parameters simultaneously. Therefore, if the F2-layer trends are primarily controlled by the geomagnetic activity, the hmF2 long-term trends should also demonstrate corresponding temporal and spatial variation. The aim of this paper is to study hmF2 long-term trends in order to check if the results may be reconciled with the proposed geomagnetic control hypothesis.
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Persistence of the planetary wave type oscillations in <i>fo</i>F2 over Europe

Persistence of the planetary wave type oscillations in <i>fo</i>F2 over Europe

The planetary waves propagating upwards from the tro- posphere have to pass through the lower ionosphere (h < 100 km). Investigations of the transient planetary wave ac- tivity in the lower ionosphere (in its ionized component) are based on the long-term measurements of the radio-wave absorption in the lower ionosphere over Europe by the A3 method (continuous wave, oblique incidence on the iono- sphere). The planetary wave activity has been studied in the period range of 3–15 days. The best-developed and most persistent spectral peaks in the range of 3–15 days over the 1980s occurred near 5 and 10 days (Laˇstoviˇcka and Pancheva, 1991). They are consistent with the eigenperi- ods of the atmosphere of about 2, 5, 10 and 16 days. The planetary wave type oscillations were shown to be caused by the planetary wave type oscillations in the neutral atmo- sphere, and not by solar or geomagnetic activity (Pancheva et al., 1989; Pancheva and Laˇstoviˇcka, 1989). Model compu- tations confirmed adequate transformation of planetary wave type oscillations in the neutral atmosphere into waves in the radio-wave absorption (Laˇstoviˇcka et al., 1994). The plane- tary wave type oscillations in the lower ionosphere have been studied in a series of papers, e.g. Laˇstoviˇcka and Pancheva (1991), Laˇstoviˇcka et al. (1994), Laˇstoviˇcka (1997, 2001 and references herein), Pancheva and Laˇstoviˇcka (1998). The planetary wave activity in the lower ionosphere is higher in winter than in summer due to the different conditions of the upward penetration of planetary waves, and it exhibits a slight trend of increasing amplitude (e.g. Laˇstoviˇcka, 2001)
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Variable long-term trends in 100+ mineral prices

Variable long-term trends in 100+ mineral prices

• The USGS website has annual data for 101 non-energy minerals from 1900 (in many cases) through 2010. Both nominal unit values and real unit values, using the U.S. CPI as the deflator, are available. This allows for a rather exhaustive coverage of the mineral commodities.

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Catalytic activity of cGMP-dependent protein kinase type I in intact cells is independent of N-terminal autophosphorylation.

Catalytic activity of cGMP-dependent protein kinase type I in intact cells is independent of N-terminal autophosphorylation.

As shown in Fig. 3A (upper panels), VASP phosphorylation was induced in wild-type MEFs by treatment with 8-Br-cGMP, 8-Br- cGMP and 8-Br-cAMP, or CNP for 15 min at 37 uC. In cGKI- deficient MEFs, 8-Br-cGMP and CNP did not induce VASP phosphorylation, confirming that the cGMP-induced VASP phosphorylation observed in wild-type cells was indeed mediated by cGKI. Combined treatment with 8-Br-cGMP and 8-Br-cAMP still resulted in an increase of phospho-VASP in cGKI-deficient MEFs, most likely because 8-Br-cAMP had activated the cAMP- dependent protein kinase. Surprisingly, although our stimulation protocol clearly induced cGKI phosphotransferase activity in intact MEFs, our phospho-specific cGKI antisera did not detect epitopes on the Western blot that could potentially represent autophosphorylated cGKI species, both under basal and stimu- lated conditions, and when huge amounts of protein (50 m g) were Figure 2. Validation of phospho-specific antisera by ELISAs with antigenic peptides (A–C) and Western blotting with purified proteins (D). Three polyclonal rabbit antisera were analyzed for their specificity and sensitivity to detect distinct phospho-sites of cGKIa (affinity- purified antiserum AffPS3, and non-purified antiserum PS6) or cGKIb (non-purified antiserum PS7). (A–C) ELISAs were used to test binding of the antisera to non-phosphorylated (grey bars) and phosphorylated (black bars) peptide antigens (for peptide IDs and sequences, see Table 1). Data shown are means from three independent experiments 6 SEM; *p#0.05, **p#0.01, ***p#0.001. (D) Western blot detection of autophosphorylated cGKIa and cGKIb by the antisera. Purified cGKI isoforms were incubated in the absence or presence of 0.1 mM ATP for 15 min at 30uC. Aliquots of the reactions were subsequently treated with lambda protein phosphatase (lPP) for 90 min at 30uC. Proteins (20 ng) were separated on SDS gels and Western blots were probed with a pan-(nonphospho-specific) cGKI antibody that detects both cGKIa and cGKIb in their non-phosphorylated state (upper panels), and with the newly generated phospho-specific antisera. Data shown in D are representative for at least three independent experiments.
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The Activity Patterns of a Group of Cantor Dusky Leaf Monkeys (<I>Trachypithecus  obscurus halonifer</I>)

The Activity Patterns of a Group of Cantor Dusky Leaf Monkeys (<I>Trachypithecus obscurus halonifer</I>)

Feeding Resting Moving Allogrooming Autogrooming Vocalization P l aying.[r]

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Long lasting protein synthesis- and activity-dependent spine shrinkage and elimination after synaptic depression.

Long lasting protein synthesis- and activity-dependent spine shrinkage and elimination after synaptic depression.

In order for such remodeling to occur, certain inputs within a dendritic branch would be selectively potentiated and strength- ened, while others would be selectively reduced or eliminated. Evidence indeed demonstrates that a subset of coactive inputs may be selectively strengthened following synaptic potentiation [9], although the counterpart of such plasticity during synaptic depression is unknown. Here we demonstrate the structural correlates of a protein synthesis dependent form of long-term depression (LTD) mediated by group I metabotropic glutamate receptors (mGluRs). Using two-photon imaging of dendritic spines in hippocampal neurons, we have shown that the global induction of mGluR-LTD leads to a significant and long lasting shrinkage and elimination of spines. We further determine that this form of structural plasticity requires the production of new proteins as well as synaptic activity. These findings demonstrate that indeed, bidirectional forms of plasticity correlate with bidirectional structural changes. Taken together, they provide a key mechanism by which to cluster synapses, allowing the pruning of specific inputs, based on the nature of the activity, and not necessarily depending on the initial size of the spines. These data also point to the dysregulation of mGluR signaling as a potential cause of the altered spine morphology seen in mental retardation disorders.
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German cultural standards from the Portuguese perspective

German cultural standards from the Portuguese perspective

German, very surprised, said he couldn’t see that, because if in Germany they knew that was being done like that, and that he had authorized it, he would be in trouble. Mr. Jacinto told him not to worry because that would work. The German said he knew that it would work but he knew that in three or four weeks it would break again, but at that time, the farmer said that after four weeks he would finish the harvest and at that time he could stop and take the machine to the workshop for 6 months if needed. For the German’s despair, the machine started working without being repaired with the special tools. The German spent the way back saying he hadn’t seen anything of that, and he was very concerned because they could fire him. The true is that the machine worked, it did the harvest and then went to the workshop and was repaired according to the German regulations, as Mr J. was a very competent technician who knew very well what he was doing. From that time, the German who often came to Portugal said, as a joke, "ah the Portuguese tool, the “arrrame” (wire) and “marrtelo” (hammer).”
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Solar zenith angle dependencies of F1-layer, <i>Nm</i>F2 negative disturbance, and G-condition occurrence probabilities

Solar zenith angle dependencies of F1-layer, <i>Nm</i>F2 negative disturbance, and G-condition occurrence probabilities

Abstract. Experimental data acquired by the Ionospheric Digital Database of the National Geophysical Data Center, Boulder, Colorado, from 1957 to 1990, are used to study the dependence of the G condition, F1-layer, and NmF2 nega- tive disturbance occurrence probabilities on the solar zenith angle during summer, winter, spring, and autumn months in latitude range 1 (between −10 ◦ and +10 ◦ of the geomag- netic latitude, 8), in latitude range 2 (10 ◦ < |8| ≤ 30 ◦ ), in latitude range 3 (30 ◦ < |ϕ| ≤ 45 ◦ , 30 ◦ < |8| ≤ 45 ◦ ), in latitude range 4 (45 ◦ < |ϕ| ≤ 60 ◦ , 45 ◦ < |8| ≤ 60 ◦ ), and in latitude range 5 (60 ◦ < |8| ≤ 90 ◦ ), where ϕ is the geographic latitude. Our calculations show that the G con- dition is more likely to occur during the first half of a day than during the second half of a day, at all latitudes during all seasons for the same value of the solar zenith angle. The F1-layer occurrence probability is larger in the first half of a day in comparison with that in the second half of a day for the same value of the solar zenith angle in latitude range 1 for all seasons, while the F1-layer occurrence probability is ap- proximately the same for the same solar zenith angle before and after noon in latitude ranges 4 and 5. The F1-layer and G condition are more commonly formed near midday than close to post sunrise or pre-sunset. The chance that the day- time F1-layer and G condition will be formed is greater in summer than in winter at the given solar zenith angle in lat- itude ranges 2–5, while the F1-layer occurrence probability is greater in winter than in summer for any solar zenith angle in latitude range 1. The calculated occurrence probability of the NmF2 weak negative disturbances reaches its max- imum and minimum values during daytime and night-time conditions, respectively, and the average night-time value of this probability is less than that by day for all seasons in all studied latitude regions. It is shown that the NmF2 normal, strong, and very strong negative disturbances are more fre- quent on average at night than by day in latitude ranges 1 and 2 for all seasons, reaching their maximum and minimum occurrence probability values at night and by day, respec-
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Antibacterial Activity of <i>Pinus pinaster</i> Bark Extract and its Components Against Multidrug-resistant Clinical Isolates of <i>Acinetobacter baumannii</i>

Antibacterial Activity of <i>Pinus pinaster</i> Bark Extract and its Components Against Multidrug-resistant Clinical Isolates of <i>Acinetobacter baumannii</i>

extract, the reduction in the number of A. baumannii isolates belonging to European clone I and II was 85.8 ± 2.5 %, 78.5 ± 1.1 %, 66.3 ± 2.5 % and 90.2 ± 1.7 %, 78.6 ± 1.2 %, 69.8 ± 0.7 %, respectively. Sev- eral basic components: caffeic acid, catechin, epicatechin, gallic acid and vanillin, detected in the extract by high performance liquid chromatography, contributed to the antibacterial activity of the extract against both clones of A. baumannii. However, the antibacterial activity of extract was higher than that of each tested basic component suggesting that proanthocyanidins, which were present in quite a large amount in the extract, might have also contributed to the activity of the extract. Antibacterial activity of PABE against A. baumannii reveals that complex and inexpensive natural product might be useful in combat against natu- rally competent bacteria that easily acquire resistance against antibiotics.
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Long-term evaluation of physical activity habits after epilepsy surgery

Long-term evaluation of physical activity habits after epilepsy surgery

The study was approved by the Human Research Ethic Committee and all subjects signed an informed consent. The studied population consisted of patients submitted to cortico-amigdalo-hippocampectomy who were referred to Hospital Brigadeiro, São Paulo, Brazil. All patients underwent surgery for treatment of refractory seizures with the same neurosurgeon. All had a preoperative multidisciplinary evaluation, including history and physical examination, long-term video-EEG monitoring, magnetic resonance imaging and neuropsychological testing. Preoperative and postoperative data were recorded for each patient in a prospective database containing complete preoperative and postoperative clinical data. Information relevant to this study included gender, age at surgery, type of operation, date of operation, presence or absence of postoperative seizures, date of the first postoperative seizure (if one occurred) and postoperative seizure frequency (if any).
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A data portal for regional climatic trend analysis in a Peruvian High Andes region

A data portal for regional climatic trend analysis in a Peruvian High Andes region

Abstract. In the frame of a Swiss-Peruvian climate change adaptation initiative (PACC), operational and historical data series of more than 100 stations of the Peruvian Meteorological and Hydrological Service (SENAMHI) are now accessible in a dedicated data portal. The data portal allows for example the comparison of data series or the interpolation of spatial fields as well as download of data in various data formats. It is thus a valuable tool supporting the process of data homogenisation and generation of a regional baseline climatol- ogy for a sound development of adequate climate change adaptation measures. The procedure to homogenize air-temperature and precipitation data series near Cusco city is outlined and followed by an exemplary trend analysis. Local air temperature trends are found to be in line with global mean trends.
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Investigating annual and monthly trends in precipitation structure: an overview across Portugal

Investigating annual and monthly trends in precipitation structure: an overview across Portugal

The analyses of partial trends in the time series revealed a sequence of alternating periods of decreasing and increasing trends in annual and monthly precipitation, and these are sometimes statistically significant. These contiguous periods, exhibiting distinct tendencies, are defined by turning points in the behaviour of precipitation which are times of significant change in the properties of precipitation. The study of monthly precipitation suggested that redistribution of precipitation during the year took place over several decades, which means that some seasons were wetter while others were drier. However, results also show that this behaviour is not persistent and that changes can occur rapidly, in terms of the relevant time scales being discussed here. The limited number and origin of the precipitation time series used in this work means that it is not possible to perceive the presence of regional patterns. This issue is more pertinent for the Azores and Madeira, where the spatial variability of precipitation is very marked; at the same time, the homogeneity tests identified some probable problems in the data that may reduce the usefulness of some of the time series for trend studies and, therefore, affect the reliability of the results. It is noticeable, however, that over the longest period of records, which ranges from 88 to 145 years, March exhibits a decreasing trend in all the ten stations in mainland Portugal, seven of which are statistically significant at the 5% significance level. This type of behaviour was not revealed by the data from the islands, for this study. There is evidence that global and local factors can both affect the spatial distribution of trends in mainland Portugal and in the Portuguese archipelagos, which has been also reported in the literature for other locations in the Iberian Peninsula and nearby territories (see e.g. Zhang et al., 1997; Lionello et al., 2006; de Lima et al., 2007; Costa et al., 2010; Gonz´alez- Hidalgo et al., 2010; Mourato et al., 2010).
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Prevalent Long-Term Trends of Hypertension in Austria: The Impact of Obesity and Socio-Demography.

Prevalent Long-Term Trends of Hypertension in Austria: The Impact of Obesity and Socio-Demography.

Reportedly greater hypertension prevalence among men than women [20,24] was not found for Austria. In our study the prevalence was higher in women and more pronounced among obese subjects. It should be pointed out that the association between hypertension and obesity is stronger in women than in men [25]. A possible reason is that the visceral fat, that is mainly located in the abdominal area and creates an increased risk for the development of fatal dis- eases, grows with age. This is more common among women than men [26]. Preventive strate- gies in Austria should thus be developed from a gender perspective. The increasing prevalence of hypertension among older subjects correlates with a rising BMI at later age in Austria [8]. Therefore, the proportion of elderly obese persons with hypertension is high and was shown to strongly increase during the investigation period. A further reason for the high prevalence of hypertension among older subjects is the fact that the blood vessel elasticity decreases with age. The progressive loss of vascular elasticity especially increases systolic blood pressure. Conse- quently, elderly patients with progressive vascular stiffness often develop systolic blood pres- sure values over 140 mmHg, while diastolic values remain under 90 mmHg, i.e. normal. This phenomenon is called increased pulse pressure. The higher the pulse pressure, the more rigid the blood vessels. The majority of hypertensive patients aged 50 years and older have this form of hypertension, which may therefore be justly called a disease of older people that increases with age [4,27]. The observed growing trend for hypertension prevalence among older Aus- trian adults is also due to the increased proportion of older people during the investigation period, an aspect which has entailed a steady increase ofthe number of chronic diseases includ- ing hypertension.
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Decadal-scale changes of dinoflagellates and diatoms in the anomalous baltic sea spring bloom.

Decadal-scale changes of dinoflagellates and diatoms in the anomalous baltic sea spring bloom.

The algal spring bloom in the Baltic Sea represents an anomaly from the winter-spring bloom patterns worldwide in terms of frequent and recurring dominance of dinoflagellates over diatoms. Analysis of approximately 3500 spring bloom samples from the Baltic Sea monitoring programs revealed (i) that within the major basins the proportion of dinoflagellates varied from 0.1 (Kattegat) to .0.8 (central Baltic Proper), and (ii) substantial shifts (e.g. from 0.2 to 0.6 in the Gulf of Finland) in the dinoflagellate proportion over four decades. During a recent decade (1995–2004) the proportion of dinoflagellates increased relative to diatoms mostly in the northernmost basins (Gulf of Bothnia, from 0.1 to 0.4) and in the Gulf of Finland, (0.4 to 0.6) which are typically ice-covered areas. We hypothesize that in coastal areas a specific sequence of seasonal events, involving wintertime mixing and resuspension of benthic cysts, followed by proliferation in stratified thin layers under melting ice, favors successful seeding and accumulation of dense dinoflagellate populations over diatoms. This head- start of dinoflagellates by the onset of the spring bloom is decisive for successful competition with the faster growing diatoms. Massive cyst formation and spreading of cyst beds fuel the expanding and ever larger dinoflagellate blooms in the relatively shallow coastal waters. Shifts in the dominant spring bloom algal groups can have significant effects on major elemental fluxes and functioning of the Baltic Sea ecosystem, but also in the vast shelves and estuaries at high latitudes, where ice-associated cold-water dinoflagellates successfully compete with diatoms.
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The Effects of Batch Reactor Extraction on Antioxidant Activity from <i>Scurulla atropurpurea</i>

The Effects of Batch Reactor Extraction on Antioxidant Activity from <i>Scurulla atropurpurea</i>

However different situation was happened on the total phenolic content assay. The increasing value again at 160°C after decreasing moment that begins at 120°C can caused by temperature extraction is too high. Not only flavonoid compound was extracted but also the hemicelluloses and lignin in the benalu teh were decomposed. Moreover, at temperature 100°C obtained the optimum extract of flavonoid compound inside the benalu teh thus at high temperature, solvent inside the batch reactor was kept in the liquid state due to the addition of pressure. Then solvent’s polarity was decreased and antioxidant solubility was increased, as temperature increased (Kruse and Dinjus, 2007).
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J. bras. pneumol.  vol.41 número4

J. bras. pneumol. vol.41 número4

will eventually result in toxicity. Therefore, low rates of SBRT-related toxicity essentially depend on reducing the volume of this shell. This can be achieved with high-dose conformal radiation around the target and a rapid decrease in dose levels around it (defined as high dose gradient). The use of SBRT requires a high level of accuracy throughout the treatment process. Such accuracy is achieved through the integration of modern imaging, simulation, planning, and dose delivery technologies and is maintained during treatment delivery (Figure 1).

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Radioterapia estereotáxica extracraniana em câncer de pulmão: atualização.

Radioterapia estereotáxica extracraniana em câncer de pulmão: atualização.

Uma meta-análise que selecionou estudos publicados entre 2000 e 2012 comparou diretamente os resultados do tratamento com SBRT ou com cirurgia em pacientes com CPCNP operáveis (estádio I). Foram selecionados 40 estudos (30 retrospectivos), somando 4.850 pacientes tratados com SBRT e 23 estudos (todos retrospectivos), totalizando 7.051 pacientes tratados com cirurgia. O grupo de tratados com SBRT apresentou mediana de idade de 74 anos, enquanto, para o grupo de tratados com cirurgia, essa foi de 66 anos. Nos grupos SBRT e cirurgia, a mediana de tempo de seguimento foi de 28 e 37 meses, respectivamente. As sobrevidas em 1, 3 e 5 anos, respectivamente, foram menores para o grupo SBRT (83,4%, 56,6% e 41,2%), comparadas ao grupo tratado com lobectomia (92,5%, 77,9% e 66,1%) e ao grupo tratado com ressecções limitadas (93,2%, 80,7% e 71,7%). Ajustando para a proporção de pacientes operáveis e idade, ambos os métodos terapêuticos apresentaram sobrevida global e sobrevida livre de doença semelhantes. Portanto, é evidente que existe uma seleção de pacientes submetidos a um ou a outro tratamento, sendo os mais idosos submetidos à SBRT e os mais jovens e em melhores condições clínicas, à cirurgia. (65)
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