Characterization of gas phase WC2+: a thermodynamically stable carbide dication

International audienceUsing an ab initio methodology, we performed a detailed theoretical study of the gas phase WC2+ dication.These calculations were done using a multiconfigurational method in connection with a large basisset, where relativistic effects were taken into account. This dication is identified here as the firstthermochemically stable doubly charged diatomic carbide in the gas phase. Our work hence confirmsthe stability of this dication in the gas phase and its earlier observations by atom probe massspectrometry. Our calculations show that the shape of the potential energy curves of its lowestelectronic states changes drastically upon consideration of relativistic effects. For instance, theelectronic ground state possesses a Morse-like potential without spin–orbit that evolves to the usualvolcanic behavior, and with a columbic 1/R evolution at large internuclear separation after inclusion ofspin–orbit. We predict a set of thermochemical and spectroscopic data for this molecular species

Knowledge and practice of first aid among parents attending primary health care centers in Madinah City, Saudi Arabia, A cross sectional study

Background: Rapid and right intervention of parents can limit disability and increase the chances of survival of the injured child and make a big difference in the outcome. Objectives: The objective of this study is to assess the knowledge and practice of first aid among parents attending PHCs in Al-Madinah city, 2017. Methods: A cross-sectional study was conducted in governmental primary healthcare centers in Al-Madinah Al-Munawwarah city (Saudi Arabia) during the year 2017. A representative sample of Saudi parents who live in Madinah and came to family medicine clinic in PHC was included. A pre-validated and self-administered questionnaire was used for data collection. Results: The study included 390 parents. More than half of them (55.6%) were males. The age of 40% of them ranged between 31 and 40 years whereas that of 31.5% ranged between 20 and 30 years. Majority of the parents (97.2%) were aware of first aid. The most commonly reported source of information about first aid was mass media (59%). Majority of the parents (93.3%) believe there must be training in first aid, and only 34.6% of them claimed that they attended a training course in first aid. The highest average knowledge percentage was observed regarding the first aid of diabetes mellitus (68.8%), followed by epilepsy (49.7%), incidents (37.5%) and finally injuries/fractures (36.7%). Higher educated parents, those with a moderate number of children (4–6), those reported nurses as the main source of information, those previously attended training in first aid, and those who had experience with incidents among their children expressed higher significantly first aid knowledge compared to their counterparts. Conclusions: First aid of various illnesses among parents in Al-Madinah city is not satisfactory, particularly regarding incidents, injuries, and fractures. However, the majority of them were willing to attend training courses in first aid at primary healthcare centers

A soft alignment model for bug deduplication

ABSTRACT: Bug tracking systems (BTS) are widely used in software projects. An important task in such systems consists of identifying duplicate bug reports, i.e., distinct reports related to the same software issue. For several reasons, reporting bugs that have already been reported is quite frequent, making their manual triage impractical in large BTSs. In this paper, we present a novel deep learning network based on soft-attention alignment to improve duplicate bug report detection. For a given pair of possibly duplicate reports, the attention mechanism computes interdependent representations for each report, which is more powerful than previous approaches. We evaluate our model on four well-known datasets derived from BTSs of four popular open-source projects. Our evaluation is based on a ranking-based metric, which is more realistic than decision-making metrics used in many previous works. Achieved results demonstrate that our model outperforms state-of-the-art systems and strong baselines in different scenarios. Finally, an ablation study is performed to confirm that the proposed architecture improves the duplicate bug reports detection

An experimental and kinetic modeling study of the ignition delay characteristics of binary blends of ethane/propane and ethylene/propane in multiple shock tubes and rapid compression machines over a wide range of temperature, pressure, equivalence ratio, and dilution

In this work, the ignition delay time characteristics of C2 – C3 binary blends of gaseous hydrocarbons including ethylene/propane and ethane/propane are studied over a wide range of temperatures (750 – 2000 K), pressures (1 – 135 bar), equivalence ratios (φ = 0.5 – 2.0) and dilutions (75 – 90%). A matrix of experimental conditions is generated using the Taguchi (L9) approach to cover the range of conditions for the validation of a chemical kinetic model. The experimental ignition delay time data are recorded using low- and high-pressure shock tubes and two rapid compression machines (RCM) to include all of the designed conditions. These novel experiments provide a direct validation of the chemical kinetic model, NUIGMech1.1, and its performance is characterized via statistical analysis, with the agreement between experiments and model being within ~ 26.4% over all of the conditions studied, which is comparable with a general absolute uncertainty of the applied facilities (~ 20%). Sensitivity and flux analyses allow for the key reactions controlling the ignition behavior of the blends to be identified. Subsequent analyses are performed to identify those reactions which are important for the pure fuel components and for the blended fuels, and synergistic/antagonistic blending effects are therefore identified over the wide range of conditions. The overall performance of NUIGMech1.1 and the correlations generated are in good agreement with the experimental data.The authors would like to express their gratitude to Science Foundation Ireland (SFI) via their Research Centre Program through project numbers 15/IA/3177 and 16/SP/3829, KAY-ICHEC via the project ngche079c, and to Shell Research Ltd. The authors from PCFC RWTH Aachen University would like to recognize the funding support from the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) through the project number –322460823 (HE7599/2–1).peer-reviewe