scholarly journals On the radial abundance gradients of nitrogen and oxygen in the inner Galactic disc

2021 ◽  
Vol 502 (1) ◽  
pp. 225-241
Author(s):  
K Z Arellano-Córdova ◽  
C Esteban ◽  
J García-Rojas ◽  
J E Méndez-Delgado
Keyword(s):  
Strong Dependence ◽  
Far Infrared ◽  
Published Data ◽  
H Ii Regions ◽  
Chemical Abundances ◽  
Data Set ◽  
Substantial Change ◽  
Small Dispersion ◽  
Additional Sample ◽  
Fir Spectra

ABSTRACT We present optical spectra of nine Galactic H ii regions observed with the 10.4 m Gran Telescopio Canarias telescope and located at Galactocentric distances (RG) from 4 to 8 kpc. The distances of the objects have been revised using Gaia DR2 parallaxes. We determine the electron temperature for all the nebulae, which allows a precise computation of their ionic abundances. We have included published data of an additional sample of Galactic H ii regions, providing a final data set of 42 objects. The shape of the radial gradients of O/H and N/H is linear and constant, discarding any substantial change of the slope, at least for RG between 4 and 17 kpc. The small dispersion of the O/H and N/H values with respect to the computed gradients imply the absence of significant azimuthal variations of the chemical abundances, at least in the quadrant covered by our observations. We find an almost flat N/O versus O/H diagram relation. This result is not observed in other nearby spiral galaxies except M31. Finally, we compare our computed gradients with those obtained using far-infrared (FIR) spectra. We confirm the significant offset in the N/O distribution between the optical and FIR observations. Possible explanations involve ionization correction factors and the strong dependence on density of the abundance determinations based on FIR lines.

Estimating performance from capabilities in business process improvement

2016 ◽  
Vol 22 (6) ◽  
pp. 1099-1117 ◽  
Author(s):  
Boyd A. Nicholds ◽  
John P.T. Mo
Keyword(s):  
Process Improvement ◽  
Business Process ◽  
Expected Improvement ◽  
Management Decision ◽  
Published Data ◽  
Performance Gain ◽  
Data Set ◽  
Business Process Improvement ◽  
Improvement Project ◽  
Content Type

Purpose The research indicates there is a positive link between the improvement capability of an organisation and the intensity of effort applied to a business process improvement (BPI) project or initiative. While a degree of stochastic variation in applied effort to any particular improvement project may be expected there is a clear need to quantify the causal relationship, to assist management decision, and to enhance the chance of achieving and sustaining the expected improvement targets. The paper aims to discuss these issues. Design/methodology/approach The paper presents a method to obtain the function that estimates the range of applicable effort an organisation can expect to be able to apply based on their current improvement capability. The method used analysed published data as well as regression analysis of new data points obtained from completed process improvement projects. Findings The level of effort available to be applied to a process improvement project can be expressed as a regression function expressing the possible range of achievable BPI performance within 90 per cent confidence limits. Research limitations/implications The data set applied by this research is limited due to constraints during the research project. A more accurate function can be obtained with more industry data. Practical implications When the described function is combined with a separate non-linear function of performance gain vs effort a model of performance gain for a process improvement project as a function of organisational improvement capability is obtained. The probability of success in achieving performance targets may be estimated for a process improvement project. Originality/value The method developed in this research is novel and unique and has the potential to be applied to assessing an organisation’s capability to manage change.

Relative testis size and mating systems in anurans: large testis in multiple-male mating in foam-nesting frogs

2011 ◽  
Vol 61 (2) ◽  
pp. 225-238 ◽  
Author(s):  
Wen Bo Liao ◽  
Zhi Ping Mi ◽  
Cai Quan Zhou ◽  
Ling Jin ◽  
Xian Han ◽  
...  
Keyword(s):  
Sperm Competition ◽  
Published Data ◽  
Male Mating ◽  
Data Sets ◽  
Testis Size ◽  
Data Set ◽  
Monogamous Species ◽  
Large Testis ◽  
Testes Size ◽  
Testis Mass

AbstractComparative studies of the relative testes size in animals show that promiscuous species have relatively larger testes than monogamous species. Sperm competition favours the evolution of larger ejaculates in many animals – they give bigger testes. In the view, we presented data on relative testis mass for 17 Chinese species including 3 polyandrous species. We analyzed relative testis mass within the Chinese data set and combining those data with published data sets on Japanese and African frogs. We found that polyandrous foam nesting species have relatively large testes, suggesting that sperm competition was an important factor affecting the evolution of relative testes size. For 4 polyandrous species testes mass is positively correlated with intensity (males/mating) but not with risk (frequency of polyandrous matings) of sperm competition.

scholarly journals On the Spectral and Polarimetric Signatures of a Bright Scatterer before and after Hardware Replacement

2021 ◽  
Vol 13 (5) ◽  
pp. 919
Author(s):  
Marco Gabella
Keyword(s):  
Low Noise ◽  
Low Noise Amplifiers ◽  
Doppler Velocity ◽  
Data Set ◽  
Differential Phase Shift ◽  
Spectral Signatures ◽  
Average Value ◽  
Before And After ◽  
Radar Calibration ◽  
Small Dispersion

A previous study has used the stable and peculiar echoes backscattered by a single “bright scatterer” (BS) during five winter days to characterize the hardware of C-band, the dual-polarization radar located at Monte Lema (1625 m altitude) in Southern Switzerland. The BS is the 90 m tall metallic tower on Cimetta (1633 m altitude, 18 km range). In this note, the statistics of the echoes from the BS were derived from other ten dry days with normal propagation conditions in winter 2015 and January 2019. The study confirms that spectral signatures, such as spectrum width, wideband noise and Doppler velocity, were persistently stable. Regarding the polarimetric signatures, the large values (with small dispersion) of the copolar correlation coefficient between horizontal and vertical polarization were also confirmed: the average value was 0.9961 (0.9982) in winter 2015 (January 2019); the daily standard deviations were very small, ranging from 0.0007 to 0.0030. The dispersion of the differential phase shift was also confirmed to be quite small: the daily standard deviation ranged from a minimum of 2.5° to a maximum of 5.3°. Radar reflectivities in both polarizations were typically around 80 dBz and were confirmed to be among the largest values observed in the surveillance volume of the Monte Lema radar. Finally, another recent 5-day data set from January 2020 was analyzed after the replacement of the radar calibration unit that includes low noise amplifiers: these five days show poorer characteristics of the polarimetric signatures and a few outliers affecting the spectral signatures. It was shown that the “historical” polarimetric and spectral signatures of a bright scatterer could represent a benchmark for an in-depth comparison after hardware replacements.

scholarly journals Children with 5′-end NF1 gene mutations are more likely to have glioma

2017 ◽  
Vol 3 (5) ◽  
pp. e192 ◽  
Author(s):  
Corina Anastasaki ◽  
Stephanie M. Morris ◽  
Feng Gao ◽  
David H. Gutmann
Keyword(s):  
Gene Mutation ◽  
Statistical Significance ◽  
Gene Mutations ◽  
Neurofibromatosis Type ◽  
Published Data ◽  
Data Sets ◽  
Nonsense Mutations ◽  
Data Set ◽  
Nf1 Gene ◽  
The Relationship

Objective:To ascertain the relationship between the germline NF1 gene mutation and glioma development in patients with neurofibromatosis type 1 (NF1).Methods:The relationship between the type and location of the germline NF1 mutation and the presence of a glioma was analyzed in 37 participants with NF1 from one institution (Washington University School of Medicine [WUSM]) with a clinical diagnosis of NF1. Odds ratios (ORs) were calculated using both unadjusted and weighted analyses of this data set in combination with 4 previously published data sets.Results:While no statistical significance was observed between the location and type of the NF1 mutation and glioma in the WUSM cohort, power calculations revealed that a sample size of 307 participants would be required to determine the predictive value of the position or type of the NF1 gene mutation. Combining our data set with 4 previously published data sets (n = 310), children with glioma were found to be more likely to harbor 5′-end gene mutations (OR = 2; p = 0.006). Moreover, while not clinically predictive due to insufficient sensitivity and specificity, this association with glioma was stronger for participants with 5′-end truncating (OR = 2.32; p = 0.005) or 5′-end nonsense (OR = 3.93; p = 0.005) mutations relative to those without glioma.Conclusions:Individuals with NF1 and glioma are more likely to harbor nonsense mutations in the 5′ end of the NF1 gene, suggesting that the NF1 mutation may be one predictive factor for glioma in this at-risk population.

scholarly journals Do Attentional Lapses Account for the Worst Performance Rule?

2021 ◽  
Vol 10 (1) ◽  
pp. 2
Author(s):  
Christoph Löffler ◽  
Gidon T. Frischkorn ◽  
Jan Rummel ◽  
Dirk Hagemann ◽  
Anna-Lena Schubert
Keyword(s):  
Time Distribution ◽  
Hierarchical Modeling ◽  
Reaction Times ◽  
Empirical Support ◽  
Response Time Distribution ◽  
Self Report ◽  
Task Completion ◽  
Published Data ◽  
Data Set ◽  
Attentional Lapses

The worst performance rule (WPR) describes the phenomenon that individuals’ slowest responses in a task are often more predictive of their intelligence than their fastest or average responses. To explain this phenomenon, it was previously suggested that occasional lapses of attention during task completion might be associated with particularly slow reaction times. Because less intelligent individuals should experience lapses of attention more frequently, reaction time distribution should be more heavily skewed for them than for more intelligent people. Consequently, the correlation between intelligence and reaction times should increase from the lowest to the highest quantile of the response time distribution. This attentional lapses account has some intuitive appeal, but has not yet been tested empirically. Using a hierarchical modeling approach, we investigated whether the WPR pattern would disappear when including different behavioral, self-report, and neural measurements of attentional lapses as predictors. In a sample of N = 85, we found that attentional lapses accounted for the WPR, but effect sizes of single covariates were mostly small to very small. We replicated these results in a reanalysis of a much larger previously published data set. Our findings render empirical support to the attentional lapses account of the WPR.

scholarly journals Applications and benefits of using gradient percentage depth dose instead of percentage depth dose for electron and photon beams in radiotherapy

2021 ◽  
Vol 27 (1) ◽  
pp. 25-29
Author(s):  
Labinot Kastrati ◽  
Gezim Hodolli ◽  
Sehad Kadiri ◽  
Elvin Demirel ◽  
Lutfi Istrefi ◽  
...  
Keyword(s):  
Electron Beams ◽  
Published Data ◽  
Photon Beams ◽  
Data Set ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Electron And Photon

Abstract Introduction: The aim of this study is to analyze the gradient of percentage depth dose for photon and electron beams of LINACs and to simplify the data set. Materials and Methods: Dosimetry measurements were performed in accordance with Technical Reports Series No. 398 IAEA. Results and discussion: The gradient of percentage depth dose was calculated and compared with the available published data. Conclusion: Instead of percentage depth dose for increasing and decreasing parts, the findings suggest using only two numbers for specific gradient of dose, separately. In this way, they can replace the whole set of the percentage depth dose (PDD).

scholarly journals Whip: Communicate and Test What to Expect from Data

2018 ◽  
Vol 2 ◽  
pp. e25317
Author(s):  
Stijn Van Hoey ◽  
Peter Desmet
Keyword(s):  
Data Quality ◽  
Controlled Vocabulary ◽  
Published Data ◽  
Data Set ◽  
Data Publication ◽  
Use Of Data ◽  
Maximum Utility ◽  
Group 2 ◽  
Publication Guidelines ◽  
Available Information

The ability to communicate and assess the quality and fitness for use of data is crucial to ensure maximum utility and re-use. Data consumers have certain requirements for the data they seek and need to be able to check if a data set conforms with these requirements. Data publishers aim to provide data with the highest possible quality and need to be able to identify potential errors that can be addressed with the available information at hand. The development and adoption of data publication guidelines is one approach to define and meet those requirements. However, the use of a guideline, the mapping decisions, and the requirements a dataset is expected to meet, are generally not communicated with the provided data. Moreover, these guidelines are typically intended for humans only. In this talk, we will present 'whip': a proposed syntax for data specifications. With whip, one can define column-based constraints for tabular (tidy) data using a number of rules, e.g. how data is structured following Darwin Core, how a term uses controlled vocabulary values, or what the expected minimum and maximum values are. These rules are human- and machine-readable, which communicates the specifications, and allows to automatically validate those in pipelines for data publication and quality assessment, such as Kurator. Whip can be formatted as a (yaml) text file that can be provided with the published data, communicating the specifications a dataset is expected to meet. The scope of these specifications can be specific to a dataset, but can also be used to express expected data quality and fitness for use of a publisher, consumer or community, allowing bottom-up and top-down adoption. As such, these specifications are complementary to the core set of data quality tests as currently under development by the TDWG Biodiversity Data Quality Task 2 Group 2. Whip rules are currently generic, but more specific ones can be defined to address requirements for biodiversity information.

scholarly journals Does the Baltic Dry Index predict economic activity in South Africa? A review from 1985 to 2016

2018 ◽  
Vol 21 (1) ◽  
Author(s):  
Kurt Sartorius ◽  
Benn Sartorius ◽  
Dino Zuccollo
Keyword(s):  
South Africa ◽  
Economic Activity ◽  
Research Question ◽  
Share Price ◽  
Series Data ◽  
Published Data ◽  
Data Set ◽  
Wide Range ◽  
The Baltic ◽  
Baltic Dry Index

Background: The ability of the Baltic Dry Index to predict economic activity has been evaluated in a number of developed and developing countries. Aim: Firstly, the article determines the primary factors driving the dynamics of the Baltic Dry Index (BDI) and, secondly, whether the BDI can predict future share price reactions on the Johannesburg Stock Exchange All Share Index (JSE ALSI), South Africa. Setting: This article investigates the dynamics and predictive properties of the BDI in South Africa between 1985 and 2016. Methods: The article uses a review of a wide range of published data and two time-series data sets to adopt a mixed methods approach. An inductive contents analysis is used to answer the first research question and a combination of a unit root test, correlation analysis and a Granger causality model is employed to test the second research question. Results: The results show that the BDI price is primarily driven by four underlying constructs that include the supply and demand for dry bulk shipping, as well as risk, cost and logistics management factors. Secondly, the results indicate a break in the BDI data set in July 2008 that influences a fundamental change in its relationship with the JSE ALSI index. In the pre-break period (1985 to 2008), the BDI is positively correlated with the ALSI (0.837, α = 0.05) before sharply diverging in the second period from August 2008 to 2016. In the first period, the BDI showed an optimal lag period of 6 months as a predictor of the ALSI index, but this predictive ability ceases after July 2008. The article makes a two-part contribution. Firstly, it demonstrates that the BDI is a useful predictor of future economic activity in an African developing country. Secondly, the BDI can be incorporated in government and industry sector planning models as a variable to assess future gross domestic product trends. Conclusion: The study confirms that the BDI is only a reliable indicator of future economic activity when the supply of shipping capacity is well matched with the demand.

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