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The aim of this study is to investigate the impact of anatomical changes in prostate cancer patients on the target coverage when using 6 MV beams-VMAT therapy and to propose strategies that allow us to evaluate the dose or correct it by normalization without having to perform a new simulation.
Methods and materials:
Ten patients of high-risk prostate cancer were chosen for the study. All test plans were delivered using the same isocenter and monitor units as the original plan and compared against the original unedited plan. The expansion and contraction of body contours due to size changes was mimicked by increasing and decreasing the body contour with depths of −2, −1·5, …, 1·5, 2 cm, in the anterior, and both lateral directions of the patient. A total of 90 plans were evaluated, 9 for each patient. Dose-volume histogram statistics were extracted from each plan and normalized to prescription dose.
Weight changes resulted in considerable dose modifications to the target and critical structures. Plans were found to be varied with 2·9% ± 0·3% per cm SSD change for VMAT treatment with a correlation index close to one. Therefore, doses variations were linear to the changes of depth. Gamma index evaluation was performed for the 10 renormalized plans. All of them passed criteria of 3%/3 mm in at least 98.2% of points. Eight of them passed criteria in 99% points. Gamma index 4%/4 mm passed 100% points in all patients for the chosen region of interest.
The dosimetry estimation presented in this study shows important data for the radiation oncology staff to justify whether a CT rescan is necessary or not when a patient experiences weight changes during treatment. Based on the results of our study, discrepancies between real dose and planned dose were >5% for 1·7 cm of difference in external contour in the anterior and both lateral directions of the patient.
The timing of the late Middle Paleolithic and late disappearance of Neanderthals in the Iberian Peninsula are hotly debated subjects in Paleolithic archeology. Several studies suggested a late survival in South and Central Iberia until about 32 ka, but were probably subject to significant age underestimation due to contamination of dating samples, undiagnostic lithic assemblages, and/or lack of stratigraphic integrity. We conducted a radiocarbon and luminescence-dating study backed by detailed sedimentological and micromorphological investigations at the newly discovered rock shelter sequence of Abrigo del Molino (Central Spain). Accumulation of the sediment sequence was rapid. It started with deposition of paleoflood slack-water deposits at around 48 ka and continued until about 41 ka with deposition of colluvial and detrital sediments. These contain two Mousterian levels, which place the latest Neanderthal occupation at around 45 to 41 ka, i.e., between Heinrich Stadials 5 and 4, and probably during a time of climate amelioration. Abrigo del Molino thus provides a detailed and chronologically well-constrained record of Late Neanderthal presence and morphodynamic change in Central Iberia during times of millennial-scale climate changes. The site gives further evidence for an early disappearance of Neanderthals in Central Iberia.
The main objective was to analyze relationships and predictive patterns between 3x2 classroom goal structures (CGS), and motivational regulations, dimensions of self-concept, and affectivity in the context of secondary education. A sample of 1,347 secondary school students (56.6% young men, 43.4% young women) from 10 different provinces of Spain agreed to participate (M age = 13.43, SD = 1.05). Hierarchical regression analyses indicated the self-approach CGS was the most adaptive within the spectrum of self-determination, followed by the task-approach CGS. The other-approach CGS had an ambivalent influence on motivation. Task-approach and self-approach CGS predicted academic self-concept (p < .01; p < .001, respectively; R2 = .134), and both along with other-approach CGS (negatively) predicted family self-concept (p < .05; p < .001; p < .01, respectively; R2 = .064). Physical self-concept was predicted by the task-approach and other-approach CGS’s (p < .05; p < .001, respectively; R2 = .078). Finally, positive affect was predicted by all three approach-oriented CGS’s (p < .001; R2 = .137), whereas negative affect was predicted by other-approach (positively) and self-approach (negatively) CGS (p < .001; p < .05, respectively; R2 = .028). These results expand the 3x2 achievement goal framework to include environmental factors, and reiterate that teachers should focus on raising levels of self- and task-based goals for students in their classes.
There is accumulating evidence for the role of fronto-striatal and associated circuits in obsessive–compulsive disorder (OCD) but limited and conflicting data on alterations in cortical thickness.
To investigate alterations in cortical thickness and subcortical volume in OCD.
In total, 412 patients with OCD and 368 healthy adults underwent magnetic resonance imaging scans. Between-group analysis of covariance of cortical thickness and subcortical volumes was performed and regression analyses undertaken.
Significantly decreased cortical thickness was found in the OCD group compared with controls in the superior and inferior frontal, precentral, posterior cingulate, middle temporal, inferior parietal and precuneus gyri. There was also a group x age interaction in the parietal cortex, with increased thinning with age in the OCD group relative to controls.
Our findings are partially consistent with earlier work, suggesting that group differences in grey matter volume and cortical thickness could relate to the same underlying pathology of OCD. They partially support a frontostriatal model of OCD, but also suggest that limbic, temporal and parietal regions play a role in the pathophysiology of the disorder. The group x age interaction effects may be the result of altered neuroplasticity.
The spatial and orientational distribution in a dilute active suspension of non-Brownian run-and-tumble spherical swimmers confined between two planar hard walls is calculated theoretically. Using a kinetic model based on coupled bulk/surface probability density functions, we demonstrate the existence of a concentration wall boundary layer with thickness scaling with the run length, the absence of polarization throughout the bulk of the channel, and the presence of sharp discontinuities in the bulk orientation distribution in the neighbourhood of orientations parallel to the wall in the near-wall region. Our model is also applied to calculate the swim pressure in the system, which approaches the previously proposed ideal-gas behaviour in wide channels but is found to decrease in narrow channels as a result of confinement. Monte Carlo simulations are also performed for validation and show excellent quantitative agreement with our theoretical predictions.
One of the most remarkable developments of modern finance was the emergence of a public debt. Governments of different kingdoms – including papal kingdoms – were able to increase their resources due to credit and, more importantly, these governments were able to make payments abroad through bankers who had previously lent the funds. These bankers lent money in order to finance armies or wars, and their loans constituted short-term debt. The development of this system in Castile began at the end of the fifteenth century, when the Catholic kings needed loans in order to conquer the Muslim city of Granada. Scholars have highlighted this event as the origin of Charles V's loans; so, the fiscal and financial system of the Habsburg dynasty had precedents before 1516.
Charles V's fiscal system took its influences from Castile and the Low Countries. The administration was built in a previous period (the Contadurías of Castile) and the reforms of 1523–5 were influenced by the model of Flanders. But, if there is an area in which tradition and innovation went together, it was debt. Castile had several types of debt and credit systems in place dating from the fourteenth and fifteenth centuries, while the Catholic kings continued with a new type of juros with more modern elements. Why did public credit arrive? Traditionally, scholars have always recognized that there was the need to increase expenses to build a new model of army, and this would include a process of authority centralization and fiscal increases. In this paper, we argue about the importance of financial markets in attracting more resources to Castile in the first decades of the sixteenth century. The increase of expenditure was very important, of course; this increase, however, would not have been possible without a new context. Money, credit, merchant networks and, in general, a very good economic situation characterized this context. Moreover, production growth and merchant profits were a reliable source of potential income for the monarchy. We cannot forget that the fiscal system was a way to earn money as well.
A new generation of radio telescopes with unprecedented capabilities for astronomy and fundamental physics will be in operation over the next few years. With high sensitivities and large fields of view, they are ideal for cosmological applications. We discuss their uses for cosmology focusing on the observational technique of HI intensity mapping, in particular at low redshifts (z < 4). This novel observational window promises to bring new insights for cosmology, in particular on ultra-large scales and at a redshift range that can go beyond the dark energy domination epoch. In terms of standard constraints on the dark energy equation of state, telescopes such as Phase I of the SKA should be able to obtain constrains about as well as a future galaxy redshift surveys. Statistical techniques to deal with foregrounds and calibration issues, as well as possible systematics are also discussed.
The reform of the pension system of the Mexican Social Security Institute (IMSS) in 1997, limited the growing fiscal cost of the previous pay-as-you-go scheme. Sixteen years on from its creation, the Retirement Savings System (SAR) has had favourable macroeconomic effects for Mexico, as it has significantly increased financial savings and encouraged the development of local financial markets.
However, the employment and pension coverage has not developed as hoped, due to the high rate of informality in the labour market. In addition, the replacement rates (RR) forecast for old-age pensions from the defined-contribution scheme will be low, due to problems exogenous to the pension system, such as low contribution rates and low contribution densities. The main objective of this study is to develop a macroeconomic and actuarial projection model to simulate the expected coverage and RR for the period 2012–2050, within the framework of a demographic and economic forecast that will allow a detailed diagnosis of the current conditions of the pension system. The results reveal the unpromising scenario that the pension system has and will continue to have in the long term, with limited improvements in coverage rates. The possibility of obtaining adequate pensions will be restricted to those who have socioeconomic conditions with a long employment history, who can thus make contributions to their individual accounts.
Taking into account this baseline projection scenario, we simulate the expected effects of applying a set of proposals with the aim of tackling the main problems, such as the low coverage, low RR, and low level of participation by young people in the system.
We describe an opinion mining system which classifies the polarity of Spanish texts. We propose an NLP approach that undertakes pre-processing, tokenisation and POS tagging of texts to then obtain the syntactic structure of sentences by means of a dependency parser. This structure is then used to address three of the most significant linguistic constructions for the purpose in question: intensification, subordinate adversative clauses and negation. We also propose a semi-automatic domain adaptation method to improve the accuracy of our system in specific application domains, by enriching semantic dictionaries using machine learning methods in order to adapt the semantic orientation of their words to a particular field. Experimental results are promising in both general and specific domains.
The pollack, Pollachius pollachius, is an important commercial species for the Spanish artisanal fleet in Atlantic Iberian waters. This study provides information on the reproductive biology of the species, including length at maturity, reproductive cycle and gamete development pattern based on histological methods. A collection of 622 individuals were sampled from fish markets along the western coast of Galicia (NW Spain), between November 2009 and October 2010. Histological examination of the gonads revealed an asynchronous development of secondary growth follicles. Testicular tissue was of lobular type. The reproductive season extended from January to April for females and from January to May for males, with a peak of reproductive activity in February for both sexes. The hepatosomatic index was related to the reproductive cycle, with a mean maximum value during the developing reproductive phase. Length at 50% maturity was significantly different between females (47.1 cm) and males (36.1 cm).
Relatively little is known of the use of systematic review and synthesis
methods of non-randomised psychiatric epidemiological studies, which play
a vital role in aetiological research, planning and policy-making.
To evaluate reviews of psychiatric epidemiological studies of functional
mental disorders that employed synthesis methods such as systematic
review or meta-analysis, or other forms of quantitative review.
We searched the literature to identify appropriate reviews published
during the period 1996 to April 2009. Selected reviews were evaluated
using published review guidelines.
We found 106 reviews in total, of which 38 (36%) did not mention method
of data abstraction from primary studies at all. Many failed to mention
study quality, publication bias, bias and confounding. In 73 studies that
performed a meta-analysis, 58 (79%) tested for heterogeneity and of
these, 47 found significant heterogeneity. Studies that detected
heterogeneity made some allowance for this. A major obstacle facing
reviewers is the wide variation between primary studies in the use of
instruments to measure outcomes and in sampling methods used.
Many deficiencies found in systematic reviews are potentially remediable,
although synthesis of primary study findings in a field characterised by
so many sources of heterogeneity will remain challenging.
Mental and physical disorders are associated with total disability, but
their effects on days with partial disability (i.e. the ability to
perform some, but not full-role, functioning in daily life) are not well
To estimate individual (i.e. the consequences for an individual with a
disorder) and societal effects (i.e. the avoidable partial disability in
the society due to disorders) of mental and physical disorders on days
with partial disability around the world.
Respondents from 26 nationally representative samples (n
= 61 259, age 18+) were interviewed regarding mental and physical
disorders, and day-to-day functioning. The Composite International
Diagnostic Interview, version 3.0 (CIDI 3.0) was used to assess mental
disorders; partial disability (expressed in full day equivalents) was
assessed with the World Health Organization Disability Assessment
Schedule in the CIDI 3.0.
Respondents with disorders reported about 1.58 additional disability days
per month compared with respondents without disorders. At the individual
level, mental disorders (especially post-traumatic stress disorder,
depression and bipolar disorder) yielded a higher number of days with
disability than physical disorders. At the societal level, the population
attributable risk proportion due to physical and mental disorders was 49%
and 15% respectively.
Mental and physical disorders have a considerable impact on partial
disability, at both the individual and at the societal level. Physical
disorders yielded higher effects on partial disability than mental
This chapter reviews the emerging paradigm of machine-to-machine (M2M) communications in the context of smart grids. Commencing here with an introduction to the topic at hand, we then introduce in subsequent sections available M2M communications technologies as well as the applicability of said technologies. We then dwell in greater detail on M2M architectural standards bodies, such as ETSI M2M and 3GPP MTC. We finally position the use of M2M in smart grids and identify open challenges for a symbiotic development of both technologies.
A machine-to-machine network is defined to be a network formed by devices that communicate with each other without (or with very little) human intervention in order to accomplish some specific task(s). The prime driver for this networking paradigm is the ability of a large number of devices/machines to execute tasks in an autonomous (and often distributed) manner which is beyond the ability of humans. From a technical point of view, it requires the system to be scalable, power-efficient, autonomous, intelligent; among many other properties, some of which are discussed below. Indeed, as highlighted throughout this book as well as below in Section 6.5, a huge number of points in the power grid need to be constantly monitored and controlled to ensure smart operation of the system.
Although the above design aims have been conceptually the core to various prior networking design efforts, the idea of M2M is currently receiving great attention from both academia and industry.
We show in this article that it is possible to obtain elemental compositional maps and profiles with atomic-column resolution across an InxGa1−xAs multilayer structure from 5th-order aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) images. The compositional profiles obtained from the analysis of HAADF-STEM images describe accurately the distribution of In in the studied multilayer in good agreement with Muraki's segregation model [Muraki, K., Fukatsu, S., Shiraki, Y. & Ito, R. (1992). Surface segregation of In atoms during molecular beam epitaxy and its influence on the energy levels in InGaAs/GaAs quantums wells. Appl Phys Lett61, 557–559].