Miracle-dz/UniFAR-FTUs huggingface dataset:
„Trading Rules“ contra „Buy & Hold“: Überzeugt der Vergleich?

Die bei Marktpraktikern sehr häufig verwendete technische Analyse gilt bei Theoretikern eher als obskur. Technische Analyse liefert Prognosen von Finanzkursen allein aus der Fortschreibung vergangener Kurszeitreihen. Dies macht dann Sinn, wenn Kurse sich mit bestimmten Regelmäßigkeiten entwickeln. Wäre dies aber so, würde es gleichzeitig eine ineffiziente Informationsverarbeitung implizieren. Stärker noch, es wäre eine sehr triviale Ineffizienz, da die vergangenen Kurse leicht zugänglich sind und keinerlei ökonomischer Sachverstand zu ihrer Interpretation erforderlich ist. Daß ausgerechnet gut organisierte Finanzmärkte in solch trivialer Weise ineffizient sein sollen, überzeugt sicher nicht auf Anhieb. Da auf der anderen Seite so zahlreiche, auch professionelle Akteure auf das Instrument der technischen Analyse zurückgreifen, ist eine Auseinandersetzung damit unverändert aktuell. Tatsächlich hat der frühe exemplarische Nachweis von Fama/Blume (1966) für US-Aktien, daß technische Analyse keine systematischen Überrenditen erbringt, nicht von zahlreichen Folgeuntersuchungen und noch weniger von ihrer praktischen Anwendung abgehalten. In diese Kette von akademischen Studien reiht sich auch der Beitrag von Stöttner (1992, im folgenden nur mit Seitenangaben zitiert) ein, der für ein internationales Portfolio über einen Zeitraum von bis zu 15 Jahren hinweg eine sehr hohe Überrendite der von ihm vorgeschlagenen Trading Rules festgestellt. Im folgenden wird begründet, warum der vorgenommene Vergleich m.E. nicht überzeugt: Erstens werden die Alternativen zur technischen Analyse nicht ganz fair dargestellt, zweitens entspricht das methodische Vorgehen kaum den etablierten Standards, drittens gibt es einige sehr fragwürdige Dateneigentümlichkeiten, viertens ist die Interpretation der Ergebnisse bei kritischer Betrachtung nicht haltbar und fünftens läßt sich die gestellte Aufgabe nachweislich befriedigender lösen.
Effective fractionation of lignocellulose in herbaceous biomass and hardwood using a mild acetone organosolv process

Large-scale biorefineries converting lignocellulosic biomass into chemicals, fuels and energy require a cost-effective pretreatment process that can effectively fractionate the three main lignocellulose constituents from a wide variety of feedstocks. A mild organosolv process has been developed using acetone as solvent. Herbaceous biomass (wheat straw and corn stover), hardwood (beech, poplar and birch) and softwood (spruce and pine) were fractionated using near-identical process conditions: 140 °C, 120 min, 50% w/w aqueous acetone and sulfuric acid. For herbaceous biomass and hardwood, effective pretreatment and subsequent enzymatic cellulose hydrolysis into glucose was observed in combination with a high yield of monomeric hemicellulose sugars and lignin. In the case of softwood, poor delignification hampered enzymatic cellulose hydrolysis, despite efficient hemicellulose removal. To assess solvent stability, the impact of temperature, time and acid dose on the degree of acetone self-condensation was explored. The process conditions used for feedstock screening resulted in a 1.4% w/w conversion of acetone to mainly diacetone alcohol and mesityl oxide. For wheat straw, shortening the reaction time to 60 min resulted in reduced solvent self-condensation (1.0% w/w) and improved hemicellulose sugar yield (86%). In sum, effective fractionation was demonstrated for various herbaceous and hardwood feedstocks combined with limited acetone loss due to self-condensation.
Mating system of the tent-making bat Artibeus watsoni (Chiroptera: Phyllostomidae)

Abstract Vertebrate mating systems are influenced by ecological and phylogenetic factors, and the variation observed in mating behavior is frequently attributable to the extent to which male assistance in the rearing of offspring increases a female's reproductive rate, size and stability of female groups, and density and distribution of females in space. In this study we evaluate patterns of association and parentage to describe the mating system of the tent-making bat Artibeus watsoni. During 16 consecutive months, we regularly surveyed 2 sites in southwestern Costa Rica and determined size, composition, and stability of social groups, and established patterns of parentage within roosts. We found female-biased, mixed-sex social groups formed by individuals located in several roosts within an area. Roosting associations were low (average across all sites: 31%), and the frequent changes between roosting partners suggests that males and females formed nonexclusive mating bonds, which was further supported by our finding that only 27% of young were sired by the male within a roosting group. Paternal sibships were only observed in 17% of dyads of young roosting together, indicating that few males copulated with >1 female of the roosting group during the mating season. However, paternal sibships were only observed in Golfito, which could be explained by greater group size and stability attributable to lower roost availability. Thus, our findings are consistent with a polygynandrous mating system (2 or several males sharing access to 2 or several females, and vice versa) in which males associated intermittently with females that frequently switched roosts, and where breeding opportunities for males seemed related to the defense of roosts, roosting territories, or both.
Role of Computed Tomography in the Pre operative Diagnosis of Clear Cell Renal Carcinoma

Background: Renal cell carcinoma (RCC) accounts for 3% of all human malignant tumors. The behavior of RCC apparently depends on its subtype. CT scan can provide detailed information about the tumor itself and regarding its precise extension. The pre-histological diagnosis of clear cell renal carcinoma could be made with more precision on the basis of CT scan features and would ultimately play a major role in the prognosis and management of the disease. Objective: To determine the diagnostic accuracy of computed tomography in the diagnosis of clear cell renal carcinoma taking histopathological findings as gold standard. Methods: Total 100 patients had renal mass were included. All patients underwent contrast enhanced CT scan. On the basis of CT scan features a pre-surgical diagnosis of histological subtype of RCC, clear cell renal carcinoma was made. The patients were followed by nephrectomy. The diagnostic accuracy of CT scan was determined. Results: The male to female ratio was 3.2:1.0. Out of total study subjects 85.0% patients turned out to be renal cell carcinomas and among these 40 (47%) were right sided and 45 (53%) were left sided. The mean size of tumor was 12.75 cm. The sensitivity, specificity, and diagnostic accuracy of CT scan were 89.0%, 72.7%, and 86.0% respectively. Conclusion: The CT scan was helpful in diagnosing clear cell renal carcinoma. The most valuable parameter was the degree of enhancement of clear cell renal carcinoma with other parameters playing supplemental role.
Automated Detection of Serializability Violations under Weak Consistency

While a number of weak consistency mechanisms have been developed in recent years to improve performance and ensure availability in distributed, replicated systems, ensuring the correctness of transactional applications running on top of such systems remains a difficult and important problem. Serializability is a well-understood correctness criterion for transactional programs; understanding whether applications are serializable when executed in a weakly-consistent environment, however remains a challenging exercise. In this work, we combine a dependency graph-based characterization of serializability and leverage the framework of abstract executions to develop a fully-automated approach for statically finding bounded serializability violations under any weak consistency model. We reduce the problem of serializability to satisfiability of a formula in First-Order Logic (FOL), which allows us to harness the power of existing SMT solvers. We provide rules to automatically construct the FOL encoding from programs written in SQL (allowing loops and conditionals) and express consistency specifications as FOL formula. In addition to detecting bounded serializability violations, we also provide two orthogonal schemes to reason about unbounded executions by providing sufficient conditions (again, in the form of FOL formulae) whose satisfiability implies the absence of anomalies in any arbitrary execution. We have applied the proposed technique on TPC-C, a real-world database program with complex application logic, and were able to discover anomalies under Parallel Snapshot Isolation (PSI), and verify serializability for unbounded executions under Snapshot Isolation (SI), two consistency mechanisms substantially weaker than serializability.
N 914 o 50 GENETIC

Genetic algorithms are highly parallel, mathematical, adaptive search procedures (i.e., problem-solving methods) based loosely on the processes of natural genetics and Darwinian survival of the fittest. This paper introduces basic genetic algorithm concepts, discusses genetic algorithm applications, and presents results from a project to develop a software tool that will enable the widespread use of genetic algorithm technology.
Effect of Transcatheter Aortic Valve Replacement on Right Ventricular Systolic Function: Systematic Review and Meta-analyses

Objectives: We ought to compare the effect of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) on right ventricular systolic function (RVSF) in high risk patients with severe aortic stenosis (AS). Methodology: Data source: PubMed, EMBASE, Cochrane library, and references of selected articles. Study Endpoints: Transthoracic echocardiography was utilized to assess the change in RVSF post TAVR versus SAVR using tricuspid annular plane systolic excursion (TAPSE), and fractional area change (RVFAC). Statistical analyses: Random effect model on standardized mean difference (Hedges; g) were used together with heterogeneity assessment. Result: We included 485 patients from five single-center observational studies. TAVR had no effect while SAVR had negative effect on RVSF, and the effect was in favor of TAVR when TAVR compared to SAVR [TAPSE (g=2.88, SE=0.63, P<0.001, Q=73.18, I2=94.53, r=0.65), and RVFAC (g=0.91, SE=0.16, P<0.001, Q=2.39, I2=16.61), r=0.65]. Conclusion: Compared with SAVR, TAVR is preferred aortic intervention for patients with severe symptomatic AS and RV systolic dysfunction.
Airborne measurements of gas and particle pollutants during CAREBeijing-2008

Abstract. Measurements of gaseous pollutants – including ozone (O3), sulfur dioxide (SO2), nitrogen oxides (NOX = NO + NO2), carbon monoxide (CO), particle number concentrations (5.6–560 nm and 0.47–30 μm) – and meteorological parameters (T, RH, P) were conducted during the Campaigns of Air Quality Research in Beijing and Surrounding Regions in 2008 (CAREBeijing-2008), from 27 August through 13 October 2008. The data from a total 18 flights (70 h flight time) from near the surface to 2100 m altitude were obtained with a Yun-12 aircraft in the southern surrounding areas of Beijing (38–40° N, 114–118° E). The objectives of these measurements were to characterize the regional variation of air pollution during and after the Olympics of 2008, determine the importance of air mass trajectories and to evaluate of other factors that influence the pollution characteristics. The results suggest that there are primarily four distinct sources that influenced the magnitude and properties of the pollutants in the measured region based on back-trajectory analysis: (1) southerly transport of air masses from regions with high pollutant emissions, (2) northerly and northeasterly transport of less pollutant air from further away, (3) easterly transport from maritime sources where emissions of gaseous pollutant are less than from the south but still high in particle concentrations, and (4) the transport of air that is a mixture from different regions; that is, the air at all altitudes measured by the aircraft was not all from the same sources. The relatively long-lived CO concentration is shown to be a possible transport tracer of long-range transport from the northwesterly direction, especially at the higher altitudes. Three factors that influenced the size distribution of particles – i.e., air mass transport direction, ground source emissions and meteorological influences – are also discussed.
Motor learning through virtual reality in elderly - a systematic review

INTRODUCTION: Decline in physical function is a common feature of older age and has important outcomes in terms of physical health as it relates to quality of life. Our capacity for motor learning allows us to flexibly adapt movements to an ever-changing environment. The term Virtual Reality refers to a wide variety of methods used to simulate an alternative or virtual world. OBJECTIVE: To analyze the results shown in previous studies on motor learning with Virtual Reality use in elderly participants. METHOD: To select the articles, three steps were followed. A systematic literature review was performed without time limitation. The research was carried out using PubMed, BVS and Web of science; considering the keywords, we included articles that showed the following three terms: elderly, virtual reality and motor learning. RESULTS: The initial search yielded 49 articles. After duplicates were removed, two of the authors independently evaluated the title and abstract of each article against the study inclusion criteria. From these, 45 articles were excluded based on title and abstract. Finally, four articles met the inclusion criteria. CONCLUSION: Although few studies were conducted on motor learning in elderly people through virtual reality and, even fewer were of good quality, it was shown that elderly people, with or without a specific disease, can benefit from interventions based on virtual reality to improve motor learning skills.
A Crosstalk between Melatonin and Taste-Receptors’ Signaling Tunes Quinine-Induced Gut Hormone Secretion in Mice

Quinine consumption has been shown to reduce appetite and food intake in human and mice. Here, tested on two common mouse strains, C3H/lbg and C57BL/6J, it exerted a different effect. While quinine reduced weight gain in C3H/lbg mice, C57BL/6J were unaffected by the bitter molecule. Among the differences between the two strains, C57BL/6J present a blunted Melatonin production. In this study, we investigate if endogenous Melatonin is playing any role in the different response of C57BL/6J mice to quinine. The effect of dietary supplementation with Melatonin as well as of endogenous gastrointestinal and pineal produced Melatonin was investigated by supplementing quinine diet with pure Melatonin, L-Tryptophan or by reversion of light/dark cycle, respectively. The consumption of Melatonin reverts the phenotype and makes C57BL/6J mice sensitive to quinine. Similarly, quinine potency in C3H/ Ibg mice augments upon supplementation with exogenous Melatonin or upon increase of Melatonin endogenous levels. In vivo, as well as in in vitro cell cultures, Melatonin Receptor modulation inhibits quinine dependent secretion of Ghrelin, while potentiates quinine dependent secretion of Cholecystokinin. Acting via Melatonin Receptors, Melatonin tunes the effect of quinine, reducing and potentiating its effect in enteroendocrine cells of the upper and the lower digestive tract, respectively. Our results indicate that signaling pathways activated by Melatonin tunes the activity of Bitter Receptors located in the gastrointestinal tract.
Metallicity effects on cosmic Type Ib/c supernovae and gamma-ray burst rates

Type Ib/c supernovae (SNe Ib/c) are likely to be associated with long gamma-ray bursts (GRBs), and therefore it is important to compare the SN rate in galaxies with the GRB rate. To do this we computed SN Ib/c rates in galaxies of different morphological types (ellipticals, spirals and irregulars) by assuming different histories of star formation and different SN Ib/c progenitors. We included some recent suggestions about the dependence of the minimum mass of single Wolf–Rayet (WR) stars on the stellar metallicity and therefore on galactic chemical evolution. We adopted several cosmic star formation rates (i.e. relative to a comoving unitary volume of the Universe) as a function of cosmic time, either observationally or theoretically derived, including the one computed with our galaxy models. We then computed the cosmic SN Ib/c rates. Our results show that the predicted SN Ib/c rates in spirals and irregulars can reproduce well the present observed rates if both single WR stars and massive binary systems are taken into account as SN Ib/c progenitors. The metallicity effects on the minimum mass for single WR stars are evident mainly in the early phases of galaxy evolution and do not influence substantially the predicted local Type Ib/c rates. We reached the following conclusions. (i) The ratio cosmic GRB rate /cosmic Type Ib/c rate varies in the range 10−2–10−4 in the whole redshift range, thus suggesting that only a small fraction of all SNe Ib/c gives rise to GRBs. (ii) The metallicity dependence of SN Ib/c progenitors produces lower cosmic SN Ib/c rates at early times, for any chosen cosmic star formation rate. (iii) Different theoretical cosmic star formation rates, computed under different scenarios of galaxy formation, produce SN Ib/c cosmic rates that differ mainly at very high redshifts. However, it is difficult to draw firm conclusions on the high-redshift trend because of the large uncertainties in the data. (iv) GRBs can be important tracers of star formation at high redshifts if their luminosity function does not vary with redshift, and they can help in discriminating among galaxy formation models.
Use of remote-sensing reflectance to constrain a data assimilating marine biogeochemical model of the Great Barrier Reef

Abstract. Skillful marine biogeochemical (BGC) models are required to understand a range of coastal and global phenomena such as changes in nitrogen and carbon cycles. The refinement of BGC models through the assimilation of variables calculated from observed in-water inherent optical properties (IOPs), such as phytoplankton absorption, is problematic. Empirically derived relationships between IOPs and variables such as chlorophyll-a concentration (Chl a), total suspended solids (TSS) and coloured dissolved organic matter (CDOM) have been shown to have errors that can exceed 100 % of the observed quantity. These errors are greatest in shallow coastal regions, such as the Great Barrier Reef (GBR), due to the additional signal from bottom reflectance. Rather than assimilate quantities calculated using IOP algorithms, this study demonstrates the advantages of assimilating quantities calculated directly from the less error-prone satellite remote-sensing reflectance (RSR). To assimilate the observed RSR, we use an in-water optical model to produce an equivalent simulated RSR and calculate the mismatch between the observed and simulated quantities to constrain the BGC model with a deterministic ensemble Kalman filter (DEnKF). The traditional assumption that simulated surface Chl a is equivalent to the remotely sensed OC3M estimate of Chl a resulted in a forecast error of approximately 75 %. We show this error can be halved by instead using simulated RSR to constrain the model via the assimilation system. When the analysis and forecast fields from the RSR-based assimilation system are compared with the non-assimilating model, a comparison against independent in situ observations of Chl a, TSS and dissolved inorganic nutrients (NO3, NH4 and DIP) showed that errors are reduced by up to 90 %. In all cases, the assimilation system improves the simulation compared to the non-assimilating model. Our approach allows for the incorporation of vast quantities of remote-sensing observations that have in the past been discarded due to shallow water and/or artefacts introduced by terrestrially derived TSS and CDOM or the lack of a calibrated regional IOP algorithm.
Statistical Modeling of Malaria Incidences in Apac District, Uganda

Malaria is a major cause of morbidity and mortality in Apac district, Northern Uganda. Hence, the study aimed to model malaria incidences with respect to climate variables for the period 2007 to 2016 in Apac district. Data on monthly malaria incidence in Apac district for the period January 2007 to December 2016 was obtained from the Ministry of health, Uganda whereas climate data was obtained from Uganda National Meteorological Authority. Generalized linear models, Poisson and negative binomial regression models were employed to analyze the data. These models were used to fit monthly malaria incidences as a function of monthly rainfall and average temperature. Negative binomial model provided a better fit as compared to the Poisson regression model as indicated by the residual plots and residual deviances. The Pearson correlation test indicated a strong positive association between rainfall and malaria incidences. High malaria incidences were observed in the months of August, September and November. This study showed a significant association between monthly malaria incidence and climate variables that is rainfall and temperature. This study provided useful information for predicting malaria incidence and developing the future warning system. This is an important tool for policy makers to put in place effective control measures for malaria early enough.
Covariance-Based Transmission Power Control for Estimation over Wireless Sensor Networks

In this study, we would like to design a transmission power control mechanism for minimizing the transmit power of a wireless sensor node subject to a constraint on the quality of estimation at a remote estimator. In particular, we measure the estimation distortion by a mean square error function, and model the transmit power as a function of the packet success rate using the IEEE 802.15. 4 standard which was formed for the specification of low-data-rate and low-power wireless communication. We formulate the problem with an infinite horizon discounted cost function. We show that there is a separation between the designs of the optimal estimator and optimal transmit power policy. Then, we use dynamic programming to characterize the optimal transmit power policy in terms of the estimation error covariance. Finally, we propose approximate value iteration as an approximation algorithm to calculate a near-optimal transmit power policy.