nils-herrmann/clean_scirepeval huggingface dataset:
Influence of thermodynamics within molten pool on migration and distribution state of reinforcement during selective laser melting of AlN/AlSi10Mg composites

A transient three dimensional model for describing the thermo capillary convection and migration behavior and the resultant distribution state of reinforcing particles during selective laser melting of AlN/AlSi10Mg is proposed. The powder solid transformation, temperature dependent physical properties and interaction between the reinforcement and the melt are taken into account. The effect of the laser energy per unit length (LEPUL) on the molten pool dynamics, cooling rate and the resultant sizes and distribution state of AlN reinforcement has been investigated. It shows that the thermo capillary convection pattern changes from inward flow pattern to outward one, due to the appearance of the oxidation in molten pool. Therefore, the morphology of the top surface undergoes a continuous variation from the balling phenomenon, to the discontinuous tracks and finally to the formation of a flat and dense one. Meanwhile, both the clockwise and counterclockwise convection patterns are produced in the molten pool, caused by the interaction of reinforcing particles and the melt. An increase in LEPUL will significantly intensify the thermo capillary convection whereas result in a decrease in the cooling rate of the molten pool. As LEPUL decreases from 1800 J/m to 450 J/m, the distribution state of AlN particles changes from the severe aggregation, then to the formation of partial aggregation and finally to the homogeneous distribution in the solidified matrix. The particle sizes of AlN reinforcement are experimentally acquired, which are in a good agreement with the results predicted by simulation.
MOCVD growth of N polar GaN on on axis sapphire substrate: Impact of AlN nucleation layer on GaN surface hillock density

We report on the impact of growth conditions on surface hillock density of N polar GaN grown on nominally on axis (0001) sapphire substrate by metal organic chemical vapor deposition (MOCVD) Large reduction in hillock density was achieved by implementation of an optimized high temperature AlN nucleation layer and use of indium surfactant in GaN overgrowth. A reduction by more than a factor of five in hillock density from 1000 to 170 hillocks/cm 2 was achieved as a result. Crystal quality and surface morphology of the resultant GaN films were characterized by high resolution x ray diffraction and atomic force microscopy and found to be relatively unaffected by the buffer conditions. It is also shown that the density of smaller surface features is unaffected by AlN buffer conditions.
A CRISPR Cas9 Gene Drive System Targeting Female Reproduction in the Malaria Mosquito vector Anopheles gambiae
Venue: Nature Biotechnology

Gene drive systems that enable super Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years. We describe CRISPR Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female sterility phenotype upon disruption, and inserted into each locus CRISPR Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6% Population modeling and cage experiments indicate that a CRISPR Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect population. These findings could expedite the development of gene drives to suppress mosquito populations to levels that do not support malaria transmission.
A new approach for selecting the number of the eigenvalues in singular spectrum analysis
Venue: J. Frankl. Inst.

Singular spectrum analysis (SSA) is a reliable technique for separating an arbitrary signal from a noisy time series (signal+noise) The SSA technique is based upon two main selections: window length, L and the number of the eigenvalues, r These values play an important role for the reconstruction stage. In this paper, we introduce a new approach for selecting the optimal value of r which is based on the distribution of the eigenvalues of a scaled Hankel matrix. The proposed approach is applied to a number of simulated and real data with different structures. The results indicate that the proposed approach has potential in selecting the value of r for signal extraction.
Neural Contributions to Muscle Fatigue: From the Brain to the Muscle and Back Again.
Venue: Medicine and science in sports and exercise

During exercise, there is a progressive reduction in the ability to produce muscle force. Processes within the nervous system as well as within the muscles contribute to this fatigue. In addition to impaired function of the motor system, sensations associated with fatigue and impairment of homeostasis can contribute to the impairment of performance during exercise. This review discusses some of the neural changes that accompany exercise and the development of fatigue. The role of brain monoaminergic neurotransmitter systems in whole body endurance performance is discussed, particularly with regard to exercise in hot environments. Next, fatigue related alterations in the neuromuscular pathway are discussed in terms of changes in motor unit firing, motoneuron excitability, and motor cortical excitability. These changes have mostly been investigated during single limb isometric contractions. Finally, the small diameter muscle afferents that increase firing with exercise and fatigue are discussed. These afferents have roles in cardiovascular and respiratory responses to exercise, and in the impairment of exercise performance through interaction with the motor pathway, as well as in providing sensations of muscle discomfort. Thus, changes at all levels of the nervous system, including the brain, spinal cord, motor output, sensory input, and autonomic function, occur during exercise and fatigue. The mix of influences and the importance of their contribution vary with the type of exercise being performed.
Effect of duration of smartphone use on muscle fatigue and pain caused by forward head posture in adults
Venue: Journal of physical therapy science

The effect of duration of smartphone use on neck and shoulder muscle fatigue and pain was investigated in adults with forward head posture.  Thirty four adults with forward head posture were classified into groups by duration of smartphone use: 11 used a smartphone for 10 minutes each (group 1) 12 for 20 minutes each (group 2) and 11 for 30 minutes each (group 3) Fatigue cervical erector spinae and upper trapezius muscles was measured by electromyography, and pain before and after the experiment was evaluated using Visual Analog Scale (VAS) scores.  There was a significant difference in the degree of fatigue in the left upper trapezius muscles in group 2 and left cervical erector spinae and bilateral upper trapeziuses group 3. There was a significant difference in fatigue in the left upper trapezius in groups 1 and 3. The VAS showed significant differences in all groups before and after the experiment and between groups 1 and 3.  Pain and fatigue worsened with longer smartphone use. This study provided data on the proper duration of smartphone use. Correct posture and breaks of at least 20 minutes are recommend when using smartphones.
The affiliation between student achievement and elements of gamification in learning science
Venue: 2016 4th International Conference on Information and Communication Technology (ICoICT)

Gamification is a new form of approach that is being looked into in the world of education. With its game elements that relates to the needs of the current generation of users whose life is entangled in the world of technology. Yet the use of technology is not a one size fits all deal; thus it is important to identify how certain gamification elements influences students. This is vital point that needs to be understood before endeavouring further into the infusion of gamification in education. When achievement in academics is a norm in traditional learning; it thus becomes the benchmark of the students when it comes to assessing the level of their understanding. Therefore it is important in understanding the affiliation between student's achievement and gamification elements. A mixed method research was carried out with a group of 29 students in a secondary school in the southern Malaysian state of Johor. The subject chosen for this research was Science. The findings showed that game elements helped change the perspective of students when it came to learning with the help of technology; especially game elements. Most students related to badges as motivational push to strife harder in learning as it can be used a qualitative form of reward, as opposed to points and leader board. Despite this, there were students whom found that other gamification elements were relevant to their learning process as well. Hence, the importance of each game element is key in making gamification based learning a success.
The impacts of infusing game elements and gamification in learning
Venue: 2016 IEEE 8th International Conference on Engineering Education (ICEED)

With its interactive feature that infuses fun to motivate its users, games have been considered useful to engage the current batch of Generation Z students. With games based learning methods such as digital game based learning, serious games and more recently gamification. Yet, with the increasing tasks of teachers nowadays, the use of gamification; game elements in non gaming context, has been gaining momentum. Although there has been research that has shown the effects of gamification on learning, the fundamental of game elements on learning via traditional and online method has been less ventured into. Thus, a mixed method research was carried out using a gamification platform as a mediator for students learning Science. The eight week gamified online intervention was carried out in tandem with the traditional classroom. The game elements used were points and badges whilst leaderboard was reflected on the amount of points and badges. The findings based on the interviews with the participants found all the elements plays a part in engaging the interest of students in learning, more so badges and leaderboard. It was also identified that certain elements are preferred to acquire either online or offline.
Thin film semiconductor perspective of organometal trihalide perovskite materials for high efficiency solar cells

Organometal trihalide perovskites (OTPs) are arising as a new generation of low cost active materials for solar cells with efficiency rocketing from 3.5% to over 20% within only five years. From "dye" in dye sensitized solar cells (DSSCs) to "hole conductors" and "electron conductors" in mesoscopic heterojunction solar cells, there has been a dramatic conceptual evolution on the function of OTPs in photovoltaic devices. OTPs were originally used as dyes in Gratzel cells, achieving a high efficiency above 15% which, however, did not manifest the excellent charge transport properties of OTPs. An analogy of OTPs to traditional semiconductors. was drawn after the demonstration of highly efficient planar heterojunction structure OTP devices and the observation of their excellent bipolar transport properties with a large diffusion length exceeding 100 nm in CH3NH3PbI3 (MAPbI(3) polycrystalline thin films. This review aims to provide the most recent advances in the understanding of the origin of the high OTP device efficiency. Specifically, we will focus on reviewing the progress in understanding (1) the characterization of fantastic optoelectronic property of OTPs, (2) the unusual defect physics that originate the optoelectronic property, (3) morphology control of the perovskite film from fabrication process and film post treatment, (4) device interface and charge transport layers that dramatically impact device efficiency in the OTP thin film devices, (5) photocurrent hysteresis, (6) tandem solar cells and (7) stability of the perovskite materials and solar cell devices.
Energy absorption in lattice structures in dynamics: Experiments

Lattice structures offer the potential to relatively easily engineer specific (meso scale properties (cell level) to produce desirable macro scale material properties for a wide variety of engineering applications including wave filters, blast and impact protection systems, thermal insulation, structural aircraft and vehicle components, and body implants. The work presented here focuses on characterising the quasi static and, in particular, the dynamic load deformation behaviour of lattice samples. First, cubic, diamond and re entrant cube lattice structures were tested under quasi static conditions to investigate failure process and stress strain response of such materials. Following the quasi static tests, Hopkinson pressure bar (HPB) tests were carried out to evaluate the impact response of these materials under high deformation rates. The HPB tests show that the lattice structures are able to spread impact loading in time and to reduce the peak impact stress. A significant rate dependency of load deformation characteristics was identified. This is believed to be the first published results of experimental load deformation studies of additively manufactured lattice structures. The cubic and diamond lattices are, by a small margin, the most effective of those lattices investigated to achieve this.
Vibrational spectroscopy and dynamics of W(CO)6 in solid methane as a probe of lattice properties.
Venue: The Journal of chemical physics

Methane solids present more than one accessible crystalline phase at low temperature at zero pressure. We trap W(CO)6 in CH4 and CD4 matrices between 8 and 35 K to probe the interaction between an impurity and its surrounding molecular solid under various physical conditions. Linear and nonlinear vibrational spectroscopies of W(CO)6 highlight different kinds of interaction and reveal new and remarkable signatures of the phase transition of methane. The structures in the absorption band of the antisymmetric CO stretching mode exhibit a clear modification at the transition between phase II and phase I in CH4 and motional narrowing is observed upon temperature increase. The vibrational dynamics of this mode is probed in stimulated photon echo experiments performed with a femtosecond IR laser. A short component around 10 ps is detected in the population relaxation lifetime in the high temperature phase of solid CH4 (phase I) and disappears at lower temperatures (phase II) where the vibrational lifetime is in the hundreds of ps. The analysis of the nonlinear time resolved results suggests that the short component comes from a fast energy transfer between the vibrational excitation of the guest and the lattice in specific families of sites. Such fast transfers are observed in the case of W(CO)6 trapped in CD4 because of an energy overlap of the excitation of W(CO)6 and a lattice vibron. In solid CH4, even when these V V transfers are not efficient, pure dephasing processes due to the molecular nature of the host occur: they are temperature dependent without a clear modification at the phase transition.
Performance evaluation of ANN and ANFIS based wind speed sensor less MPPT controller
Venue: 2016 5th International Conference on Informatics, Electronics and Vision (ICIEV)

Two artificial intelligence (AI) techniques, artificial neural network (ANN) and adaptive neuro fuzzy inference system (ANFIS) have been proposed for maximum power point tracking (MPPT) of wind energy systems. Both the ANN and ANFIS based controllers have the ability to track the maximum power point (MPP) and the corresponding rotor speed of the wind generator by estimating wind speed with very little error. The ANN network utilizes feed forward back propagation algorithm to train the network during the learning process, and uses gradient decent search technique to adjust the weights between nodes to minimize the error. On the other hand, the ANFIS network combines the artificial neural network with the fuzzy decision process, making it more efficient. Neither of the algorithms requires any mechanical sensor for wind speed measurement. From the simulation results, it has been observed that the ANN as well as ANFIS methods are suitable for estimating wind speed and tracking the maximum power point and the corresponding rotor speed. ANFIS based controller, however, is more accurate and robust compared to the ANN based one in terms of wind speed estimation. Similar performances have also been noticed in the determination of maximum power and rotor speed.
Process time and MPPT performance analysis of CF, LUT, and ANN control methods for a PMSG based wind energy generation system

Due to environmental issues such as global warming and the greenhouse effect, there is a growing interest in renewable sources of energy. Wind energy, which is the most important of these energy sources, can potentially meet a portion of the global energy demand. Numerous studies are being conducted worldwide to determine how the maximum level of power can be obtained from wind energy. In these studies, there is a particular interest in permanent magnet synchronous generators (PMSGs) This is because PMSGs exhibit a good performance within a wide range wind speeds and can be driven directly. In this study, the maximum power point tracking (MPPT) of a PMSG has been carried out by using a prototype built in a laboratory environment. The simulation model has been realized by utilizing MATLAB/Simulink and implemented by using dSPACE. MPPT has been performed by employing such control algorithms as an articial neural network, a look up table, and curvetting in order to carry out comparative performance analyses of these control algorithms. Controllers were analyzed through comparisons between their MPPT and process performance. Based on our analysis results, we were able to identify controllers that were better in terms of power tracking and process performance.
Frequency Modulation based microstepping of stepper motor for real time position tracking applications
Venue: 2016 IEEE International Conference on Power Electronics, Drives and Energy Systems (PEDES)

Microstepping drive for stepper motor is a well known technique to improve stepper motor performance. Normally microstepping is carried at fixed pulse width planned. But this method is suitable only when motors are driven at fixed pre defined speeds for non real time applications. The problem discussed in this paper considers an application where motors need to track a given reference position profile in real time whose speed is varying at every interval of time. In such scenario fixed speed microstep drive does not meet the high pointing requirements and leads to poor system performance. For such applications, an innovative Frequency Modulation (FM) based microstep drive algorithm is developed which meets high degree of motor pointing even at higher output angular rates. As per this scheme, pulse width and number of steps motor supposed to move are derived from the reference position itself in a given amount of time and motor is actuated with corresponding number of steps in real time. FM based microstep drive is implemented with PWM based chopper current controller in an optimized way without compromising on the motor torque margins. The experimental results obtained are very encouraging. The paper presents the design, analysis, simulation and experimental results of FM based microstep drive.
Effects of arbuscular mycorrhizal fungi on herbivory defense in two Solanum (Solanaceae) species

Arbuscular mycorrhizal fungi (AMF) are abundant soil organisms that have wide ranging impacts on plants and ecosystems. About 80% of land plants form symbiotic relationships with AMF (Schussler et al. 2001) and these associations can affect plant growth, fitness, and community diversity (Klironomos et al. 2000, Smith Read 2008, Jung et al. 2012) AMF hyphal networks reach parts of the surrounding soil that plant roots cannot and transfer nutrients, such as phosphate and nitrogen, to the plant in exchange for carbohydrates synthesized during photosynthesis (Smith Smith 2011) The general increase in plant fitness due to AMF was historically attributed solely to the improved nutrition AMF provide (Pfleger Linderman 1994) but more recent studies have found that plants colonized by AMF undergo physiological changes that alter their resistance to aboveand belowground antagonists (Pozo et al. 2002, Koricheva et al. 2009, Song et al. 2013, Vannette et al. 2013, Cameron et al. 2013) AMF may influence plant defenses by interacting with the jasmonic acid (JA) pathway (Pozo Azcon Aguilar 2007) Jasmonic acid is an essential hormone in the immune system of plants (Bari Jones 2009, Pieterse et al. 2009) and when a plant is attacked by an insect herbivore, JA is produced, signaling cells to begin production of defensive compounds (Pozo et al. 2004) In many plants, this induced resistance includes the general defensive chemicals peroxidase (POD) polyphenol oxidase (PPO) and protease inhibitors (PI) (Farmer Ryan 1992, Constabel Ryan 1998, Moore et al. 2003) enzymes that have been shown to have inhibitory effects on insect herbivores. In Populus spp. POD inhibits herbivore growth by oxidizing phenols in the guts of caterpillars, damaging amino acids and denaturing proteins
Review of Various Herbal Supplements as Complementary Treatments for Oral Cancer
Venue: Journal of dietary supplements

In the United States, nearly 44,000 people are diagnosed with oral or pharyngeal cancer annually. The life expectancy for those who are diagnosed have a survival rate of 57% after five years. Among them, oral cancer can be classified as benign or malignant tumors and is diagnosed at several stages in the development: premalignant conditions, premalignant lesions, and malignant cancer. The early signs of oral cancer often go unnoticed by the individual and are often discovered during routine dental examinations. Early detection and treatment may help to increase patient survival rates. The most widely used treatments for oral cancer include surgery, radiation, and chemotherapy alone or in combination. Preclinical and clinical evidence for the use of green tea, raspberry, asparagus, and cannabis extracts is discussed in this review. Diet changes, supplementation with antioxidants, high dose vitamin C therapy, and cannabinoid use have been suggested to decrease cancer cell replication and increase chance of remission. Early detection and lifestyle changes, including the use of dietary supplements in at risk populations, are critical steps in preventing and successfully treating oral cancer. The main evidence for supplement use is currently in cancer prevention rather than treatment. Further research, determination, and mechanism of action for bioactive compounds such as epigallocatechin, epicatechin 3 gallate, and Bowman Birk inhibitor concentrate, through in vitro, in vivo, and clinical trials need to be completed to support the use of natural products and their effectiveness in preventative care and supporting therapeutic approaches.