Exploring the Impact of Socio-Technical Core-Periphery Structures in Open Source Software Development

In this paper we apply the social network concept of core-periphery structure to the sociotechnical structure of a software development team. We propose a socio-technical pattern that can be used to locate emerging coordination problems in Open Source projects. With the help of our tool and method called TESNA, we demonstrate a method to monitor the socio-technical core-periphery movement in Open Source projects. We then study the impact of different core-periphery movements on Open Source projects. We conclude that a steady core-periphery shift towards the core is beneficial to the project, whereas shifts away from the core are clearly not good. Furthermore, oscillatory shifts towards and away from the core can be considered as an indication of the instability of the project. Such an analysis can provide developers with a good insight into the health of an Open Source project. Researchers can gain from the pattern theory, and from the method we use to study the core-periphery movements

Why doorstepping can increase household waste recycling

AbstractIn this study we report on a doorstepping intervention which produced a 12.5%, statistically significant, increase in the recycling capture rate. More importantly, we investigate why doorstepping caused the increase, through focus groups, structured interviews and questionnaires. By analyzing the findings with respect to a pragmatic set of eleven clusters of determinants of behaviour change, we find that social norms and emotion were important, with prompts as a more minor determinant. We can now plan further doorstepping knowing an emphasis on these is useful. Knowledge, skills, belief of consequences, belief of capability, action planning, role clarification, feedback, and motivation were determinant clusters found not to be important in this case.Recycling behaviour change interventions often do not generally produce transferable learning because they are usually presented as case studies and not broken down into key elements. Our analytical approach of breaking down a poorly defined activity – doorstepping – into elements which influence different clusters of determinants, and then exploring their separate impacts, allows some predictive planning and optimization for other interventions. The specific context here was residential food waste recycling in apartment blocks of communities in Shanghai, China

Revisión sobre métodos de preparación, mecanismos y aplicaciones de péptidos antioxidantes en aceites

Natural antioxidants, especially those used in edible oil, are safer compared to chemically synthesized antioxidants. Therefore, research on natural antioxidants has become prevelant. Antioxidant peptides derived from food protein can effectively prevent oil oxidation. Protein hydrolyzation is widely applied for the production of antioxidant peptides in industry, and bioinformatics is employed nowadays to generate the desired peptide sequence. Furthermore, the mechanism of antioxidant peptides in the oil system is still controversial, which limits the further development of antioxidant peptides as food antioxidants. This review introduces the preparation method of antioxidant peptides and their mechanisms as well as applications in the oil. It will help to comprehensively understand the function of antioxidant peptides and promote their development in the oil field.Los antioxidantes naturales, especialmente utilizados en aceites comestibles, son más seguros en comparación con los antioxidantes sintetizados químicamente. Por lo tanto, la investigación sobre antioxidantes naturales se convierte en un punto de interés. Los péptidos antioxidantes derivados de las proteínas alimentarias pueden prevenir eficazmente la oxidación del aceite. La hidrolización de proteínas se usa ampliamente en la industria para la producción de péptidos antioxidantes y la bioinformática se emplea hoy en día para generar la secuencia de péptidos deseada. Además, el mecanismo de los péptidos antioxidantes en el sistema oleoso sigue siendo controvertido, lo que limita el desarrollo posterior de péptidos antioxidantes como antioxidantes alimentarios. Esta revisión presenta el método de preparación de péptidos antioxidantes y su mecanismo, así como las aplicaciones en aceite, lo que ayudará a comprender de manera integral la función de los péptidos antioxidantes y promoverá su desarrollo en el campo petrolero

Bound state solutions of the Dirac-Rosen-Morse potential with spin and pseudospin symmetry

The energy spectra and the corresponding two- component spinor wavefunctions of the Dirac equation for the Rosen-Morse potential with spin and pseudospin symmetry are obtained. The $s-$wave ($\kappa = 0$ state) solutions for this problem are obtained by using the basic concept of the supersymmetric quantum mechanics approach and function analysis (standard approach) in the calculations. Under the spin symmetry and pseudospin symmetry, the energy equation and the corresponding two-component spinor wavefunctions for this potential and other special types of this potential are obtained. Extension of this result to $\kappa \neq 0$ state is suggested.Comment: 18 page

Molecular cytogenetic aberrations in patients with multiple myeloma studied by interphase fluorescence in situ hybridization

Background: Multiple myeloma (MM) is an incurable hematological disorder characterized by the accumulation of malignant plasma cells within the bone marrow (BM). The clinical heterogeneity of MM is dictated by the cytogenetic aberrations present in the clonal plasma cells (PCs). Cytogenetic studies in MM are hampered by the hypoproliferative nature of plasma cells in MM. Therefore, fluorescence in situ hybridization (FISH) analysis combined with magnetic-activated cell sorting (MACS) is an attractive alternative for evaluation of numerical and structural chromosomal changes in MM. Methods: Interphase FISH studies with three different specific probes for the regions containing 13q14.3 (D13S319), 14q32 (IGHC/IGHV) and 1q12(CEP1 ) were performed in 48 MM patients. Interphase FISH studies with LSI IGH/CCND1, LSI IGH/FGFR3, and LSI IGH/MAF probes were used to detect t(11;14)(q13;q32), t(4;14)(p16;q32), and t(14;16)(q32;q23) in patients with 14q32 rearrangement. Results: Molecular cytogenetic aberrations were found in 40 (83.3%) of the 48 MM patients. 13 patients (27.1%) simultaneously had 13q deletion/monosomy 13 [del(13q14)], illegitimate IGH rearrangement and chromosome 1 abnormality. Del(13q14) was detected in 21 cases (43.7%), and illegitimate IGH rearrangements in 29 (60.4%) including 6 with t(11;14) and 5 with t(4;14). None of 9 patients with illegitimate IGH rearrangements and without t(11;14) or t(4;14) we detected had t(14;16) (q32;q23). 24 of the 48 MM patients (50%) had chromosome 1 abnormalities. Among 21 patients with del(13q14), 15 patients had Amp1q12;16 had IgH rearrangements. Whereas, among 27 cases without del(13q14), 8 had Amp1q12; 13 had IgH rearrangements. There was a strong association between del(13q14) and Amp1q12(c2 = 8.26, р < 0.01), and between del(13q14) and IgH rearrangement(c2 = 3.88, p < 0.05). Conclusion: 13q deletion/monosomy 13, IGH rearrangement and chromosome 1 abnormality are frequent in MM. They are not randomly distributed, but strongly interconnected. Interphase FISH technique combined with MACS using CD138-specific antibody is a highly sensitive technique at detecting molecular cytogenetic aberrations in MM.Обоснование: множественная миелома (MM) — неизлечимое гематологическое заболевание, характеризирующееся накоплением злокачественных плазматических клеток в костном мозге (КM). Клиническая гетерогенность MM определяется цитогенетическими аберрациями, присутствующими в клоне плазматических клеток (ПК). Цитогенетические исследования MM осложнены гипопролиферативными особенностями ПК. В связи с этим флуоресцентная гибридизация in situ (FISH) в комбинации с сортировкой клеток, активированных магнитными полями (MACS) представляется достойной альтернативой методам оценки точечных и структурных изменений хромосом при MM. Методы: интерфазные исследования методом FISH с использованием трех различных специфических зондов для участков, содержащих 13q14.3 (D13S319), 14q32 (IGHC/IGHV) и 1q12(CEP1), проводили у 48 больных с MM. Интерфазные исследования методом FISH с использованием зондов LSI IGH/CCND1, LSI IGH/FGFR3 и LSI IGH/MAF применяли для детекции t(11;14)(q13;q32), t(4;14)(p16;q32), и t(14;16)(q32;q23) у пациентов с перестройкой 14q32. Результаты: молекулярные цитогенетические аберрации выявляли у 40 (83,3%) из 48 больных с MM. У 13 пациентов (27,1%) одновременно определены 13q делеция/моносомия 13 [del(13q14)], аномальная перестройка IGH и аномалия хромосомы 1. Del(13q14) детектировали в 21 случае (43,7%), а аномальные перестройки IGH — в 29 (60,4%), в том числе у 6 пациентов с t(11;14) и 5 с t(4;14). Ни у одного из 9 больных с аномальными перестройками IGH и без t(11;14) или t(4;14) не выявляли транслокацию t(14;16) (q32;q23). У 24 из 48 пациентов с MM (50%) определяли аномалии хромосомы 1. В группе из 21 больных с del(13q14) в 15 случаях имелись перестройки IgH Amp1q12;16. В то же время из 27 случаев без del(13q14) у 8 содержались Amp1q12; в 13 случаях отмечали перестройки IgH. Выявлена взаимосвязь между del(13q14) и Amp1q12(χ2 = 8,26, p < 0,01) и между del(13q14) и перестройками IgH (χ2 = 3,88, p < 0,05). Выводы: 13q делецию/моносомию 13, перестройку IGH и аномалию хромосомы 1 часто отмечают при MM, причем их распределение не случайно и тесно взаимосвязано. Интерфазный анализ FISH в комбинации с MACS с использованием CD138-специфичных антител является высокочувствительным методом детекции молекулярных цитогенетических аберраций при MM

Shape and blocking effects on odd-even mass differences and rotational motion of nuclei

Nuclear shapes and odd-nucleon blockings strongly influence the odd-even differences of nuclear masses. When such effects are taken into account, the determination of the pairing strength is modified resulting in larger pair gaps. The modified pairing strength leads to an improved self-consistent description of moments of inertia and backbending frequencies, with no additional parameters.Comment: 7 pages, 3 figures, subm to PR

Efficient magneto-optical trapping of Yb atoms with a violet laser diode

We report the first efficient trapping of rare-earth Yb atoms with a high-power violet laser diode (LD). An injection-locked violet LD with a 25 mW frequency-stabilized output was used for the magneto-optical trapping (MOT) of fermionic as well as bosonic Yb isotopes. A typical number of $4\times 10^6$ atoms for $^{174}$Yb with a trap density of $\sim 1\times10^8/$cm$^3$ was obtained. A 10 mW violet external-cavity LD (ECLD) was used for the one-dimensional (1D) slowing of an effusive Yb atomic beam without a Zeeman slower resulting in a 35-fold increase in the number of trapped atoms. The overall characteristics of our compact violet MOT, e.g., the loss time of 1 s, the loading time of 400 ms, and the cloud temperature of 0.7 mK, are comparable to those in previously reported violet Yb MOTs, yet with a greatly reduced cost and complexity of the experiment.Comment: 5 pages, 3 figures, 1 table, Phys. Rev. A (to be published

Optimised limit for polarimetric calibration of fully polarised SAR systems

The optimised limit for polarimetric calibration of fully polarised synthetic aperture radar systems is derived by establishing an error model as a function of cross-talk, channel imbalance and system noise. Compared with noise equivalent sigma zero, the polarimetric error below the optimised limit is too small to affect the signal of cross-polarised channel. Thus, polarimetric calibration could be relaxed or even ignored in this case. With the backscatter model, optimised limits for cross-talk and channel imbalance at X, C and L-bands are presented. Moreover, when ignoring channel imbalance, the limit for cross-talk is given in a quantitative way. These results are very useful in practice, allowing significant reduction in calibration cost

Variability of Broad and Blueshifted Component of [OIII]λ\lambda5007 in IZWI

Although the existence of asymmetrical profile of [OIII]$\lambda$5007 has been discovered for ages, its filiation and physics are poorly understood. Two new spectra of I ZWI taken on Nov 16, 2001 and on Dec 3, 2002 were compared with the spectra taken by BG92. Following results are obtained. 1)The certain variations of broad [OIII] during about 10 years separating the observations are identified. The inferred length scale of broad [OIII] emitting region ranges from 0.3pc to 3pc. By assuming a Keplerian motion in emitting region, the material emitting broad [OIII] is likely to be located at transient emission line region, between BLR and NLR. 2)We find a positive relation between the FeII emission and flux of H$\beta$(or continuum). On the other hand, the parameter RFe decreases with ionizing continuum marginally. 3)We detect a low ionized NLR in I ZWI, because of the low flux ratios $\rm{[OIII]_{n}/H\beta_{n}}$($\sim1.7$).Comment: 14 pages, 3 figures, NewA in pres

Controlling sequential hybrid evolutionary algorithm by Q-learning

Many state-of-the-art evolutionary algoritahms (EAs) can be categorized as sequential hybrid EAs, in which various EAs are sequentially executed. The timing to switch from one EA to another is critical to the performance of the hybrid EA because the switching time determines the allocation of computational resources and thereby it helps balance exploration and exploitation. In this article, a framework for adaptive parameter control for hybrid EAs is proposed, in which the switching time is controlled by a learned agent rather than a manually designed scheme. First the framework is applied to an adaptive differential evolution algorithm, LSHADE, to control when to use the scheme to reduce the population. Then the framework is applied to the algorithm that won the CEC 2018 competition, i.e., the hybrid sampling evolution strategy (HSES), to control when to switch from the univariate sampling phase to the Covariance Matrix Adaptation Evolution Straategy phase. The agents for parameter control in LSHADE and HSES are trained by using Q-learning and deep Q-learning to obtain the learned algorithms Q-LSHADE and DQ-HSES. The results of experiments on the CEC 2014 and 2018 test suites show that the learned algorithms significantly outperform their counterparts and some state-of-the-art EAs.Algorithms and the Foundations of Software technolog