451 research outputs found
Áramlástérkép R-ben
A természeti környezet és az emberi társadalom egyaránt dinamikus rendszer, számos
eleme állandó mozgásban van: vírusok, áruk, javak, ötletek, információk, emberek, üzenetek,
az állatvilág egyedei változtatják helyüket a tér egyik pontjáról a tér másik pontjára
(Tobler 2003). Az ilyen mozgásokat általánosan térbeli interakcióknak nevezzük (Batty 2008). Az interakciók jelentős szerepet játszanak társadalmi folyamatok alakításában, sok
esetben a folyamatok meghatározó hajtóerőinek tekinthetők. Az interakciók megjelenítésének legkönnyebben értelmezhető és emiatt leggyakrabban használt eszköze az áramlástérkép
(flow map).
Tanulmányunkban az áramlástérkép R programnyelvben megvalósított változatát mutatjuk
be. Az általunk javasolt megoldás nem tartalmaz a sokak által ismert kereskedelmi
(Mapinfo, ArgGIS, Mapviewer) vagy nyílt forráskódú szoftverekhez képest új vizualizációs eljárást. Elsődleges célunk az volt, hogy felhívjuk a figyelmet az R-ben rejlő ábrázolási,
valamint adatelőkészítési lehetőségekre.
Tanulmányunkban először röviden áttekintjük térbeli áramlások ábrázolásának történeti előzményeit, utalunk a migrációs mozgások ábrázolására használt, szabadon elérhető
szoftverekre. Elemzésünkben az elmúlt negyedszázad megyei szintű állandó vándorlásainak
(belföldi vándorlások) mátrixaira támaszkodtunk. A vándorlásokat életciklushoz
viszonylag egyértelműen köthető korcsoportok szerint vizsgáltuk. Az ábrázolást a könnyebb
megértés érdekében lépésenként mutatjuk be. Tanulmányunkat a fontosabb tapasztalatok
összefoglalásával zárju
A diffúz nagy B-sejtes lymphoma modern szemlélete és kezelése | Recent advances in the understanding and treatment of diffuse large B-cell lymphoma
Absztrakt
A diffúz nagy B-sejtes lymphoma a leggyakoribb a non-Hodgkin-lymphomák között. A
ciklofoszfamid-vincristin-adriablastin-prednisolon kemoterápiával a betegeknek
már közel 50%-a meggyógyítható volt, majd a rituximab hozzáadásával a gyógyulási
arány már 60% fölé emelkedett. Ez a javulás jelentős, de további növekedést
kellene elérni a betegek gyógyulási arányában. Az utóbbi években elvégzett
genetikai vizsgálatok számos új, a patogenezisben is szerepet játszó és terápiás
célpontként is szolgáló mutációt azonosítottak a betegségben. A diagnosztika ma
már rutinszerűen alkalmazza a 18-fluoro-deoxi-glükóz-pozitronemissziós
komputertomográfiás vizsgálatokat a Lugano klasszifikációs rendszer részeként.
Ezen adatok alapján egyre pontosabban meghatározható a betegek prognózisa, és
kiválaszthatók azok a betegek, akik valamelyik új, szelektíven ható gyógyszerre
esetleg reagálhatnak. Mindezeknek a kérdéseknek a megválaszolása, az újabb
kezelések bevezetése várhatóan a közeli jövőben tovább fogja javítani a betegek
túlélési esélyeit. Az összefoglaló közlemény áttekintést ad a közelmúlt
újdonságairól, kiemeli a ma használatos és javasolt kezeléseket, továbbá
áttekintést ad a jelenleg kipróbálás alatt álló és bevezetendő kezelésekről is.
Orv. Hetil., 2016, 157(31), 1232–1241.
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Abstract
Diffuse large B-cell lymphoma is the most common type of non-Hodgkin’s lymphoma.
Using the conventional cyclophosphamide adriablastin vincristin prednisolon
polychemotherapy about 50% of the patients were cured. The addition of rituximab
to the regimen increased the cure rate to 60%. This is a major improvement,
however, further advance is still needed to increase the cure rate. The
extensive genetic testing performed recently revealed several important
pathognomic mutations as potential targets in this disease. Routine diagnosis of
patients now includes the use of 18Fluor-deoxy-glucose positron
emission computer tomography, according to the recent Lugano classification
system. With all these data we can better predict the prognosis of patients, and
we can select candidates for novel targeted therapies as well. Answering these
questions, and utilizing novel therapies possibly will further increase the cure
rate in the near future. This paper summarizes current diagnostic and
therapeutic approaches and describes recent understanding in the mutations and
pathognomic changes resulting in the disease. The authors also summarize the
data available on experimental therapies possibly entering clinical pratice in
the forthcoming years. Orv. Hetil., 2016, 157(31),
1232–1241
Extracting information from the signature of a financial data stream
Market events such as order placement and order cancellation are examples of
the complex and substantial flow of data that surrounds a modern financial
engineer. New mathematical techniques, developed to describe the interactions
of complex oscillatory systems (known as the theory of rough paths) provides
new tools for analysing and describing these data streams and extracting the
vital information. In this paper we illustrate how a very small number of
coefficients obtained from the signature of financial data can be sufficient to
classify this data for subtle underlying features and make useful predictions.
This paper presents financial examples in which we learn from data and then
proceed to classify fresh streams. The classification is based on features of
streams that are specified through the coordinates of the signature of the
path. At a mathematical level the signature is a faithful transform of a
multidimensional time series. (Ben Hambly and Terry Lyons \cite{uniqueSig}),
Hao Ni and Terry Lyons \cite{NiLyons} introduced the possibility of its use to
understand financial data and pointed to the potential this approach has for
machine learning and prediction.
We evaluate and refine these theoretical suggestions against practical
examples of interest and present a few motivating experiments which demonstrate
information the signature can easily capture in a non-parametric way avoiding
traditional statistical modelling of the data. In the first experiment we
identify atypical market behaviour across standard 30-minute time buckets
sampled from the WTI crude oil future market (NYMEX). The second and third
experiments aim to characterise the market "impact" of and distinguish between
parent orders generated by two different trade execution algorithms on the FTSE
100 Index futures market listed on NYSE Liffe
Dimension-free Euler estimates of rough differential equations
We give a dimension-free Euler estimation of solution of rough differential
equations in term of the driving rough path. In the meanwhile, we prove that,
the solution of rough differential equation is close to the exponential of a
Lie series, with a concrete error bound
A választói viselkedés térbeli modellje – empirikus kísérlet budapesti adatok alapján = A spatial model of voting behaviour - an empirical study based on Budapest data
One condition of the stable and balanced functioning of democratic systems is the active participation of citizens. Considering the political subsystem, civilian activity is primarily, although not exclusively, manifested in participation at elections. The relationship between participation in the 2010 parliamentary election and the number of votes cast in favour of the winning party was in the focus of our investigations in this study. According to Klimek et al. (2012), who greatly inspired the current research, conclusions can be drawn about the fairness of the election based on the concentration of votes cast for the winning party. This is possible because salient differences observable in the joint distributions of concentration and participation may suggest problems concerning the fairness of the election. Since the chance of salient differences occurring is negligible, these might suggest manipulation. In our study, we argue that a method which ignores spatial effects may be inefficient in the case of auto-correlated error components because the independence assumption is not met, so this method may lead to biased estimations. In order to answer the research question, we relied on data derived from voting districts in Budapest which were used to create a geo-referenced spatial point database. Data were entered by voting district, then areal data was created with the help of Voronoi tesselation. In order to shed light on the relationship between participation and the votes cast for the winning party, we relied on spatial filtering as suggested by Getis and Ord, which enables the explicit expression of spatial effects. The non-parametric Getis spatial filtering has been investigated with the help of optimal distances and first-order topological neighbourhood as well, although the method is primarily based on determining distance-based auto-correlations. The approach which took topological relations into consideration did not result in significant differences in parameter estimates, although it had a somewhat better fit (higher R2 and lower AIC value). This calls attention to the problems of applying distance approaches in the case of very unevenly sized irregular configurations. By the decomposition of variables to spatial and non-spatial components and by the explicit expression of spatial effects, the independence assumption of error components can be fulfilled. As a consequence, it is possible to return to using the traditional Ordinary Least Squares (OLS) method. The most important finding of our research was that the relationship between voting turnout and votes cast for the winning party in Budapest in 2010 was unjustifiable. Relying on the OLS method and disregarding spatial effects led to serious consequences; it resulted in biased estimations. For this reason, we emphasize the importance of handling auto-correlations properly in the case of spatial data
Transposon-based gene delivery vectors for gene therapy
The first gene therapy clinical trials were initiated more than two decades ago thanks to the previous development of viral vectors that allow high efficiency gene transfer into mammalian cells. Since then the application of viral gene transfer has been a successful treatment option for a variety of diseases. Hematopoietic stem cells (HSCs) represent the most frequently targeted cell population for the treatment of severe monogenic diseases as their gene therapeutic correction is a valid alternative to conventional HSC transplantation when a compatible donor is not available. Indeed, viral gene transfer was successfully applied in HSC-based ex vivo gene therapy of the blood and immune systems, albeit several studies have exposed serious adverse effects that were caused by the therapeutic vector induced inappropriate activation of proto-oncogenes. After these failures, researchers have developed new types of randomly integrating vectors that have proven safer in preclinical studies, which is consistent with interim reports of clinical trials also foreshadowing that they potentially have an improved safety profile. This review focuses on new and clinically relevant DNA transposon-based gene delivery vectors, and compares their properties with those of the old and new generation viral vectors
Etraffic – an Open Access Transportation Model
This paper presents a modular transportation modellingapproach. In the proposed system travel demand is determinedusing existing statistics. All data describing a national roadnetwork and corresponding traffic demand is loaded into thesoftware application, consisting of a web interface and manageddatabase. Users have access to this dataset and mayfreely modify it to create their own models and scenarios fortransportation studies
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