nils-herrmann/clean_scirepeval huggingface dataset:
Does it matter whether students enjoy learning science? exploring student attitudes towards science in South Africa

Attitudes towards science are seen as key components of an individual's scientific literacy but are often overlooked in favour of achievement scores. While achievement scores convey levels of problem solving skills and intelligence, attitudes convey the emotional evaluations of science and have a powerful influence on behaviour, either facilitating or hindering the learning process. The 2011 Trends in International Mathematics and Science Study (TIMSS)1 was used to investigate four broad categories of attitudes: value of science, enjoyment of science, confidence in ability to learn science (self efficacy) and physiological states experienced when engaging in science tasks (anxiety, stress or excitement) The findings indicate that (i) South African students' enjoyment and value of science were far higher than the international average; (ii) students with positive attitudes towards science tend to engage in desirable science behaviours, e.g. reading about science; (iii) positive experiences in the science classroom are linked to positive attitudes expressed by students; and (iv) girls tend to have less positive attitudes towards science than boys do, even when they achieve results that are at the same level as those of boys.
STABILITY OF THE GAS CORE OF A CYCLONIC TWO PHASE SEPARATOR IN MICROGRAVITY

A microgravity experiment was designed to investigate the performance of a cyclonic two phase separator. Surface tension effects could become important in microgravity, which adversely affects the separator performance. In the present study, the collapse of the gas core due to surface tension was investigated analytically as well as numerically. A control volume analysis and a volume of fluid based computational fluid dynamics (CFD) simulation were employed to determine the condition for the gas core collapse. The predicted critical Weber numbers by both methods agree reasonably well. They predict that the critical Weber number is on the order of unity in the parametric range investigated herein. For practical purposes, the critical condition is also expressed in terms of the injection Weber number.
Balance the Carrier Mobility To Achieve High Performance Exciplex OLED Using a Triazine Based Acceptor.
Venue: ACS applied materials interfaces

A star shaped 1,3,5 triazine/cyano hybrid molecule CN T2T was designed and synthesized as a new electron acceptor for efficient exciplex based OLED emitter by mixing with a suitable electron donor (Tris PCz) The CN T2T/Tris PCz exciplex emission shows a high PhPL of 0.53 and a small DET S 0.59 kcal/mol, affording intrinsically efficient fluorescence and highly efficient exciton up conversion. The large energy level offsets between Tris PCz and CN T2T and the balanced hole and electron mobility of Tris PCz and CN T2T, respectively, ensuring sufficient carrier density accumulated in the interface for efficient generation of exciplex excitons. Employing a facile device structure composed as ITO/4% ReO3:Tris PCz (60 nm)/Tris PCz (15 nm)/Tris PCz:CN T2T(1:1) (25 nm)/CN T2T (50 nm)/Liq (0.5 nm)/Al (100 nm) in which the electron hole capture is efficient without additional carrier injection barrier from donor (or acceptor) molecule and carriers mobilities are balanced in the emitting layer, leads to a highly efficient green exciplex OLED with external quantum efficiency (EQE) of 11.9% The obtained EQE is 18% higher than that of a comparison device using an exciplex exhibiting a comparable PhPL (0.50) in which TCTA shows similar energy levels but higher hole mobility as compared with Tris PCz. Our results clearly indicate the significance of mobility balance in governing the efficiency of exciplex based OLED. CN T2T exciplex as the host, we further demonstrated highly efficient yellow and red fluorescent OLEDs by doping 1 wt Rubrene and DCJTB as emitter, achieving high EQE of 6.9 and 9.7% respectively.
Using Dust Assessment Technology to Leverage Mine Site Manager Worker Communication and Health Behavior: A Longitudinal Case Study.
Venue: Journal of progressive research in social sciences

Research continues to investigate barriers to managing occupational health and safety behaviors among the workforce. Recent literature argues that (1) there is a lack of consistent, multilevel communication and application of health and safety practices, and (2) social scientific methods are absent when determining how to manage injury prevention in the workplace. In response, the current study developed and tested a multilevel intervention case study at two industrial mineral mines to help managers and workers communicate about and reduce respirable silica dust exposures at their mine sites. A dust assessment technology, the Helmet CAM, was used to identify and encourage communication about potential problem areas and tasks on site that contributed to elevated exposures. The intervention involved pre and post assessment field visits, four weeks apart that included multiple forms of data collection from workers and managers. Results revealed that mine management can utilize dust assessment technology as a risk communication tool to prompt and communicate about healthier behaviors with their workforce. Additionally, when workers were debriefed with the Helmet CAM data through the device software, the dust exposure data can help improve the knowledge and awareness of workers, empowering them to change subtle behaviors that could reduce future elevated exposures to respirable silica dust. This case study demonstrates that incorporating social scientific methods into the application of health and safety management strategies, such as behavioral modification and technology integration, can leverage managers' communication practices with workers, subsequently improving health and safety behaviors.
A complete study of the lack of compactness and existence results of a fractional Nirenberg equation via a flatness hypothesis, I

In this paper, we consider a nonlinear critical problem involving the fractional Laplacian operator arising in conformal geometry, namely the prescribed curvature problem on the standard n sphere n 2. Under the assumption that the prescribed function is flat near its critical points, we give precise estimates on the losses of the compactness and we provide existence results. In this first part, we will focus on the case 1 n 2, which was not included in the results of Jin, Li and Xiong (14) and (15) MSC 2000: 35J60, 35B33, 35B99, 35R11, 58E30.
Physiological Functions of Cyclic Electron Transport Around Photosystem I in Sustaining Photosynthesis and Plant Growth.
Venue: Annual review of plant biology

The light reactions in photosynthesis drive both linear and cyclic electron transport around photosystem I (PSI) Linear electron transport generates both ATP and NADPH, whereas PSI cyclic electron transport produces ATP without producing NADPH. PSI cyclic electron transport is thought to be essential for balancing the ATP/NADPH production ratio and for protecting both photosystems from damage caused by stromal overreduction. Two distinct pathways of cyclic electron transport have been proposed in angiosperms: a major pathway that depends on the PROTON GRADIENT REGULATION 5 (PGR5) and PGR5 LIKE PHOTOSYNTHETIC PHENOTYPE 1 (PGRL1) proteins, which are the target site of antimycin A, and a minor pathway mediated by the chloroplast NADH dehydrogenase like (NDH) complex. Recently, the regulation of PSI cyclic electron transport has been recognized as essential for photosynthesis and plant growth. In this review, we summarize the possible functions and importance of the two pathways of PSI cyclic electron transport.
A physiological role of cyclic electron transport around photosystem I in sustaining photosynthesis under fluctuating light in rice
Venue: Scientific reports

Plants experience a highly variable light environment over the course of the day. To reveal the molecular mechanisms of their photosynthetic response to fluctuating light, we examined the role of two cyclic electron flows around photosystem I (CEF PSI) one depending on PROTON GRADIENT REGULATION 5 (PGR5) and one on NADH dehydrogenase like complex (NDH) in photosynthetic regulation under fluctuating light in rice (Oryza sativa L. The impairment of PGR5 dependent CEF PSI suppressed the photosynthetic response immediately after sudden irradiation, whereas the impairment of NDH dependent CEF PSI did not. However, the impairment of either PGR5 dependent or NDH dependent CEF PSl reduced the photosynthetic rate under fluctuating light, leading to photoinhibition at PSI and consequently a reduction in plant biomass. The results highlight that (1) PGR5 dependent CEF PSI is a key regulator of rapid photosynthetic responses to high light intensity under fluctuating light conditions after constant high light; and (2) both PGR5 dependent and NDH dependent CEF PSI have physiological roles in sustaining photosynthesis and plant growth in rice under repeated light fluctuations. The highly responsive regulatory system managed by CEF PSI appears able to optimize photosynthesis and plant growth under naturally fluctuating light conditions.
The Difficult to Quantify Cyclic Electron Flux around Photosystem I in Leavesof Flowering Plants

In oxygenic photosynthesis, two photosystems (PS II and PS I) using light, work in series to extract electrons from water to generate reducing power (in the form of NADPH) in linear electron transport, while the energy of the protons after water photo oxidation is conserved in the form of ATP. Additionally, a cyclic electron flux (CEF) around PS I is also coupled to the formation of ATP  Together, NADPH and ATP drive the conversion of CO2 into carbohydrates. CEF is central to the regulation of photosynthesis [2] but its quantification, six decades after the discovery, has been difficult because of the absence of net formation of a product or consumption of a reactant
A single Eu2+ activated high color rendering oxychloride white light phosphor for white light emitting diodes
Venue: Light, science applications

Single phased, high color rendering index (CRI) white light phosphors are emerging as potential phosphor converted white light emitting diodes (WLEDs) and as an alternative to blends of tricolor phosphors. However, it is a challenge to create a high CRI white light from a single doped activator. Here, we present a high CRI (Ra 91) white light phosphor, Sr5(PO4)3 x(BO3)xCl:Eu2+ composed of Sr5(PO4)3Cl as the beginning member and Sr5(BO3)3Cl as the end member. This work utilized the solid solution method, and tunable Eu2+ emission was achieved. Color tunable Eu2+ emissions in response to structural variation were observed in Sr5(PO4)3 x(BO3)xCl solid solutions. This was further confirmed using X ray Rietveld refinement, electron paramagnetic resonance spectroscopy, and in the photoluminescence spectra. The color tunable emissions included the white light that originated from the combination of the blue emission of Sr5(PO4)3Cl:Eu2+ and an induced Eu2+ yellow emission at approximately 550 nm in the solid solution. Importantly, the white light phosphors showed a greater R9 90.2 under excitation at 365 nm. This result has rarely been reported in the literature and is greater than that of (R9 14.3) commercial Y3Al5O12:Ce3+ based WLEDs. These findings demonstrate the great potential of Sr5(PO4)3 x(BO3)xCl:0.04Eu2+ as a white light phosphor for near UV phosphor converted WLEDs. These results also provide a shortcut for developing a high CRI white light phosphor from a single Eu2+ doped compound.
A deep red phosphor Li2MgTiO4:Mn4+ exhibiting abnormal emission: Potential application as color converter for warm w LEDs

The exploration of new red phosphor based on rare earth free ion activated oxide is of great practical value in the field of phosphors converted white light emitting diode (w LED) lightings. Here, we report on a novel Mn4+ doped Li2MgTiO4 phosphor prepared by a solid state reaction route, matching with the blue chips and showing strong deep red emission with an abnormal broad band centered at ~676 nm. The crystal structure of Li2MgTiO4 is identified and investigated by Rietveld refinement. The crystal field strength (Dq) and the Racah parameters (B and C) are estimated to evaluate the nephelauxetic effect of Mn4+ suffered in Li2MgTiO4 host lattice. The calculated results well conform to show linear dependence of E(2Eg) on b1 parameter which may provide an indication of the Mn4+emission position on the basis of b1. The photoluminescence properties are investigated systematically with the aid of diffuse reflection spectra, steady and transient state fluorescence measurements at high, low and room temperature. Concentration quenching and thermal quenching are elucidated in detail. As proof of concept, the as prepared Li2MgTiO4:Mn and commercial YAG:Ce phosphors are applied to the package of a blue LED chip to fabricate a warm w LED.
A novel double perovskite Gd2ZnTiO6:Mn4+ red phosphor for UV based w LEDs: structure and luminescence properties

Red emitting Mn4+ activated oxide phosphors with a cheap price and excellent physical/chemical stability have become a hot research topic for their potential applications in white LEDs (w LEDs) Herein, we report a novel double perovskite Gd2ZnTiO6:Mn4+ (GZT:Mn4+ red phosphor. The material microstructures were characterized with the aid of XRD Rietveld refinement and HRTEM observations. The luminescence properties and dynamics of Mn4+ in GZT were studied in detail using low/room temperature steady/transient spectroscopic techniques. The crystal field strength and nephelauxetic effect influencing the Mn4+ emission energy were also analyzed. It is revealed that the special crystal structure of GZT featuring alternately slant wise arranged [TiO6][ZnO6] octahedrons with the Mn4+ O2 Zn2+ bond angle deviating from 180deg is beneficial to achieving efficient Mn4+ 2Eg 4A2 transition in the deep red region. After mixing the red emitting GZT:Mn4+ with the commercial blue and green phosphors in various ratios, and then coupling the mixture with a 365 nm UV chip to build a w LED, the white light was found to evolve from cool to warm with a tunable correlated color temperature (CCT) from 6977 K to 4742 K, a color rendering index (CRI) up to 82.9, and an improved R9 value to 43, which validates that GZT:Mn4+ is a promising red color converter for UV based w LEDs.
Near field flow of submarines and ships advancing in a stable stratified fluid

A methodology is presented to predict density stratified flows in the near field of naval vessels. The approach uses a single phase level set method for the free surface, a dynamic overset technique to handle motions and controllers for self propulsion and maneuvering. The density is solved with a higher order transport equation coupled with momentum and mass conservation. Turbulence is implemented with a k e k o based Delayed Detached Eddy Simulation (DDES) approach modified to add density gradients. Evaluation tests were performed for a two dimensional square cavity, including grid and time step studies, and the stratified flow past a sphere, showing good agreement with available data. The stratified flow was studied for a self propelled ship and a submarine. Density, velocity, pressure and turbulent quantities at the exit plane of the near field contain a description of the relevant scales of the flow and can be used to compute the far field stratified flow. It is shown that, as is the case of surface waves, the generation of internal waves requires energy that results in an increase in resistance. Moreover, the presence of a density interface against the hull results in a thickening of the boundary layer, just as in a solid/free surface juncture flow.
The Revolutionary Armed Forces of Colombia (FARC) and the Development of Narco Submarines

The Revolutionary Armed Forces of Colombia (FARC) have been one of the world's most consistently formidable violent non state actors over the last forty years. Unsurprisingly, the group has provided one of the most compelling and concerning examples of the level of technical sophistication attainable by sub state organizations. Over the last two decades the group has carried out an iterative and innovative process that, in reaction to improved detection capabilities, has brought them from depending on disposable go fast boats to transport drugs to possessing fully submersible and reusable covert vessels for transportation. The following case study will discuss the development of narco submarines and the underlying motivations behind the pursuit of this complex engineering task. The case study will outline the different phases of the narco submarine development and highlight FARC's determination to overcome the challenges present in each design. This discussion will show how FARC's systematized acquiring of information and expertise has resulted in the accomplishment of fully submersible vessels, capable of transporting more than 10 tons of illicit product.  This article forms part of a series of related case studies collected in this Special Issue and should be viewed in the context of the broader phenomenon of complex engineering by violent non state actors. Readers are advised to consult the introductory and concluding papers for a full explanation and comparative analysis of the cases. Acknowledgements This work was supported by Sandia National Laboratories,  Any opinions, findings, conclusions and recommendations in this issue are those of the authors and do not necessarily reflect views of Sandia National Laboratories or the U.S. Department of Energy.
Abiotic Stress Signaling and Responses in Plants
Venue: Cell

As sessile organisms, plants must cope with abiotic stress such as soil salinity, drought, and extreme temperatures. Core stress signaling pathways involve protein kinases related to the yeast SNF1 and mammalian AMPK, suggesting that stress signaling in plants evolved from energy sensing. Stress signaling regulates proteins critical for ion and water transport and for metabolic and gene expression reprogramming to bring about ionic and water homeostasis and cellular stability under stress conditions. Understanding stress signaling and responses will increase our ability to improve stress resistance in crops to achieve agricultural sustainability and food security for a growing world population.
Learning parameterized policies for Markov decision processes through demonstrations
Venue: 2016 IEEE 55th Conference on Decision and Control (CDC)

We consider the problem of learning a policy used by an agent in a Markov decision process using state action samples. We focus on a class of parameterized policies and use l1 regularized logistic regression to train a policy that best fits the observed state action pairs (demonstrations) We bound the difference in average reward of the trained and the original policy (regret) in terms of the generalization error and sensitivity parameters of the Markov chain. Specifically, we use techniques from sample complexity theory to relate regret to the generalization error and techniques from sensitivity analysis of the stationary distribution of Markov chains to relate regret to the ergodic coefficient of the Markov chain. We demonstrate the effectiveness of our method on a synthetic example.
OIL SPILL DETECTION AND MONITORING OF ABU DHABI COASTAL ZONE USING KOMPSAT 5 SAR IMAGERY

Abu Dhabi Government endorsed vision for its Maritime Strategy 'A safe, secure and sustainable maritime domain for Abu Dhabi' This research study share this vision using the concept of monitoring as tool for marine protection against any possible oil pollution. The best technology to detect and monitor oil pollution and in particularly oil spill is SAR imagery In this case study we chose KOMPSAT 5 SAR. KOMPSAT 5 carries X band SAR for earth observation, and is capable of day and night imaging under all weather condition. It provides three operation modes: High Resolution Mode to provide 1 m resolution, Standard Mode to provide 3 m resolution and Wide Swath Mode to provide 20 m resolution with 100 km swath at 550 km altitude, with four modes of polarization. KOMPSAT 5 provides products for various applications; security and defense, mapping, and natural resource management, environmental monitoring, disaster monitoring and more. For our case study we chose to work with Wide Swath mode (WS) with Vertical polarization (VV) to cover a wide area of interest located to the north west of Abu Dhabi including some important islands like "Zirku Island" and areas with oil production activities. The results of data acquired on 4th May 2015 show some spot of oil spill with length estimated about 3 KM, and the daily satellite data acquisition over the period July 24 through July 31 shows serious and many oil spill events some are small, but many others are considered to be big with area size around 20 km2. In the context of oil spill pollution in the seas, we have to consider the development and increase of overseas transportation, which is an important factor for both social and economic sectors. The harmful effects of marine pollution are numerous, from the damage of marine life to the damage of the aquatic ecosystem as whole. As such, the need for oil slick detection is crucial, for the location of polluted areas and to evaluate slick drift to protect the coastline. Satellite based oil spill monitoring system now can be used to take precautions and even to determine the possible polluter; it has a vital importance on the detection and protection of national and international waters from the possible damages of petroleum hazard. Finally, and as we suggested in previous studies, we recommend to the national authorities to establish a national near real time oil spill monitoring system based on SAR satellite imagery, with the support of other tools like AIS and navigation radars
Self frequency shifted solitons in a polarization maintaining, very large mode area, Er doped fiber amplifier.
Venue: Optics express

We demonstrate soliton self frequency shifted, femtosecond pulse amplification in a newly developed, polarization maintaining, Er doped, very large mode area fiber amplifier. The PM VLMA Er fiber had a core diameter of 50 mm, an effective area of ~1050 mm2, and Er absorption of 50 dB/m. The measured birefringence beat length of the PM VLMA Er fiber was 14.1 mm. The soliton wavelength could be shifted by more than 90 nm. The soliton generation process resulted in remarkably clean, 86 fs pulses with 21 nJ energy at 1650 nm and 244 kW peak power from an all fiber, fusion spliced system without bulk optics for pulse compression. The polarization extinction ratio of the soliton was greater than 40 dB, and the M2 was 1.1. The fully polarization maintaining fiber laser system provides robust and stable soliton generation. Peak to peak variation in the soliton wavelength, measured over the course of an hour was only 0.03% and pulse energy variation was only 0.5%