Miracle-dz/UniFAR-FTUs huggingface dataset:
Teachers' Assignments as Indicators of Instructional Quality in Elementary Schools. CSE Technical Report 545.

This report describes ongoing research investigating the use of teachers’ assignments as an indicator of classroom practice. The purpose of this work is to develop a measure of students’ learning environments that could potentially be used to help monitor the influence of school reform efforts on the quality of the classroom learning environment and support the improvement of instructional practice. Past research indicated good results in regard to the technical quality and feasibility of the method for describing practice in urban school environments. This report describes additional research investigating the reliability and validity of this method for describing the quality of students’ learning environments in schools serving higher achieving and middle-class elementary school students as well. Results indicated good reliability between raters, but not within raters over time. Results also indicated that the quality of assignments was statistically significantly associated with the quality of observed instruction and student work. Finally, results indicated that at least three assignments would need to be collected from teachers to determine a stable estimate of quality. Over the past two decades a number of high-profile reports, such as A Nation at Risk (National Commission on Excellence in Education, 1983), have drawn widespread attention to the quality of education in this country. Reports like these have pointed to the need to have higher standards for student learning and an improvement in the quality of instruction. In response to public concern, numerous reform programs have been launched, especially in schools serving primarily poor and minority students. Despite these efforts, however, students who are considered most at risk for academic problems have continued to perform well below state and national norms on standardized tests of achievement. A broad range of factors influence both student achievement and the quality of reform implementation. One factor that has been identified as a barrier to the success of reform efforts, however, is the difficulty of changing the nature of instruction—the most important school factor influencing student achievement (Cuban, 1990; Tharp & Gallimore, 1988). Even when teachers subscribe to a new instructional practice or seek to implement new standards for instruction, the
Speaking Rate, Information Density, and Information Rate in First-Language and Second-Language Speech

Using a corpus of multilingual recordings of a standard text (the North Wind and the Sun passage, NWS) in 11 languages, speaking rate (SR, syllables/second) and information density (ID, number of syllables for the NWS text) were examined in first-language (L1) and second-language (L2) speech. Replicating prior work, cross-language comparison of L1 speech showed a trade-off between SR and ID such that relatively low density languages (many syllables for the NWS text) tended to be produced at relatively fast rates, and vice versa. Furthermore, L2 English was characterized by both slower rate and lower ID than L1 English. That is, L2 English involved more syllables than L1 English for the same NWS text. A comparison of the number of acoustic syllables (i.e. amplitude peaks) with the number of orthographic syllables (i.e. dictionary-based syllable counts for the NWS text) indicated that L1 speech involved substantial syllable reduction (fewer acoustic than orthographic syllables) while L2 speech involved substantial syllable epenthesis (more acoustic than orthographic syllables). These findings suggest that L2 speech production involves temporal restructuring beyond increased segment, syllable and word durations, and that the resultant information rate (information bits transmitted/second) of L2 speech diverges substantially from that of L1 speech.
Retinal fine structure in the European eel Anguilla anguilla. I. Pigment epithelium of the glass eel stage.

: The catadromous migrations of the European eel (Anguilla anguilla) are accompanied by a number of morphological and biochemical alterations within the visual system. This report describes the morphology of the retinal pigment epithelium, choriocapillaris and Bruch's membrane of the yellow eel and forms the third in a series describing the morphological changes in the retina of the eel during its life cycle. The retinal epithelium of the yellow eel stage consists of a single layer of cuboidal cells joined laterally by tight junctions. Apically, numerous processes enclose photoreceptor cells while basally and laterally the cell borders are relatively smooth. Internally the epithelial cells display abundant smooth endoplasmic reticulum, mitochondria, melanosomes, phagosomes and myeloid bodies. Rough endoplasmic reticulum, polysomes and Golgi zones are present but not plentiful. The nucleus is pleiomorphic and basally located. Bruch's membrane (complexus basalis) is trilaminate. The choriocapillaris is typically fenestrated facing the retina. A stratum argenteum is present in the outer choroid and wandering phagocytes are noted at the retinal epithelium-photoreceptor interface.
Chinese postgraduate EFL learners’ self-directed use of mobile English learning resources

Abstract Despite the increasing ownership of mobile devices among Chinese postgraduate EFL learners, relevant studies regarding mobile English learning resources (MELR) use by postgraduate learners are still lacking. This study tries to understand the uses and the motivation behind language learners´ selection of MALL resources. In this research, 95 Chinese postgraduate students from four university levels took part in a questionnaire, and eight of them in an interview. The results show that “passing exams” was the top reason for using MELR and expanding one’s English vocabulary was the aspect learners aimed to improve. The portability of mobile devices enabled learners to use MELR during short time intervals 1 , which suggests that MALL applications should target this behaviour. However, as a type of supplementary material, few students used MELR for more than one hour per day, and they were not regularly and actively involved in using MELR. Few learners were able to select suitable MELR to meet their current English learning needs, and they relied on recommendations from social media and authoritative education experts. Due to the importance of vocabulary, mobile dictionaries and vocabulary learning applications were the learners’ favourite type of MELR. As the participants suggested, enjoyment and interactivity were the two driving factors behind MELR selection and use. On the basis of Framework for the Rational Analysis of Mobile Education (FRAME, Koole, M. (2009). A model for framing mobile learning. In M. Ally (Ed.), Mobile learning: Transforming the delivery of education and training. Athabasca: Athabasca University Press, 25–47) and Technology Acceptance Model (TAM [Davis, F. D., (1989). Perceived usefulness, perceived ease of use, and user acceptance of information technology. Management Information Systems, 13, 319–339]; TAM 2 [Venkatesh, V. , & Davis, F. D. (2000). A theoretical extension of the technology acceptance model: Four longitudinal field studies. Management Science, 46(2), 186–204]), a new theoretical model for better understanding the complex nature of mobile-assisted language learning (MALL) and the importance of learners in the self-directed, non-formal English language learning setting is proposed in this study.
Metabolite Profiling of 96% Ethanol Extract from Marsilea crenata Presl. Leaves Using UPLC-QToF-MS/MS and Anti-Neuroinflammatory Predicition Activity with Molecular Docking

Phytoestrogen is a group of compounds that can replace the estrogen function in the body. One of its roles was as anti-neuroinflammatory by inhibiting the microglia M1 polarity activation. Marsilea crenata Presl. is a plant that suspected to contain phytoestrogens. The aim of this research was to determine the metabolite profile of 96% ethanol extract of M. crenata using UPLC-QToF-MS/MS, and prediction the anti-neuroinflammatory activity of compounds with molecular docking. The 100 ppm of 96% ethanol extract in DCM and methanol were injected 5 µl each into the UPLC-QToF-MS/MS, and then analyzed by Masslynx 4.1 software to determine the compounds. The result of metabolite profiling shows a total 59 compounds in both DCM and methanol. Molecular docking was done with Autodock 4.2. 6. After being analyzed, there are 3 compounds that are predicted to have activities similar to 17β-estradiol, they are prochlorperazine, 12-Aminododecanoic acid, and 1-methyl-2-[(4-methylpiperazin-1-yl)methyl]benzimidaol-5-amine hydrochloride. The results showed that the three compounds were predicted to be phytoestrogen compounds from M. crenata leaves, which have potential as anti-neuroinflammatory.
Reactive Extraction of Lactic Acid using Environmentally Benign Green Solvents and Synergistic Mixture of Extractants

An environment-friendly reactive extraction method as a novel phase separation technique was postulated to extract lactic acid (LA) from aqueous solution by means of environmentally benign green solvents along with the synergistic mixture of extractants. Reactive extraction of LA has been carried by using synergistic mixture of extractants (trioctylamine (TOA), Aliquat336, and tridodecylamine (TDDA)), organic solvents, and non-toxic and biocompatible green solvents. From the different LA reactive extraction systems investigated, the system having sunflower oil, synergist extractant (TOA and Aliquat336) and Butan-2-ol were found to be the most favourable system. The LA distribution coefficient (KD=27.75±0.22) and extraction efficiency (η=97.17±0.54%) were obtained by a system consisting of LA concentration (0.05 [M]), TOA (15%, v/v), Aliquat336 (15%, v/v), solvent ratio (2.5, v/v), phase ratio (1:1, v/v), agitation speed (100 rpm), and stirring time (120 min). The main driving force for this research work on the LA reactive extraction from aqueous solution was to develop a suitable combination of extractants, organic solvents and natural solvents which possesses high affinity towards LA and also has less toxicity towards LA producing microbes.
Nonfullerene organic photovoltaic cells exhibiting 13.76% efficiency by employing upside‐down solvent vapor annealing

Organic photovoltaic cells (OPVs) are fabricated with a polymer donor PM7 and a nonfullerene acceptor IT‐4Cl; the morphology of active layers is optimized by employing upside‐down solvent vapor annealing (UD‐SVA) method with different annealing solvents. The OPVs with CS2 as annealing solvent exhibit optimized power conversion efficiency (PCE) of 13.76%, with simultaneously increased short‐circuit current density (JSC) of 20.53 mA cm−2 and fill factor (FF) of 77.05%. More than 15% PCE improvement can be achieved by employing CS2 UD‐SVA treatment, which should be attributed to slightly enhanced photon harvesting, efficient exciton separation, charge transport, and collection, resulting from the well‐developed morphology of active layer. Moreover, the PM7:IT‐4Cl–based OPVs with CS2 as annealing solvent still can maintain PCE more than 13% in a wide treatment time range from 20 to 90 seconds. This work demonstrated that UD‐SVA has great potential in improving the performance of nonfullerene OPVs.
Effects of ported shroud casing treatment on the acoustic and flow behaviour of a centrifugal compressor

Centrifugal turbomachines of smaller sizes operating at higher speeds have become pervasive due to the increased specific power and reliability achieved by improvements in manufacturing, materials and computational methods. The presence of these small turbomachines, specifically compressors, in helicopters, unmanned aerial vehicles, auxiliary power units, turbochargers and micro gas turbines necessitates superior aerodynamic performance over a broad operational range, which is widely achieved by ported shroud casing designs. In addition to aerodynamic performance, acoustic emissions have become a critical aspect of design for these small centrifugal compressors due to high operational speeds. Furthermore, the literature on the acoustic effects of the casing treatment is rather limited. Therefore, the impact of ported shroud casing treatment on the acoustic and flow features of the compressor operating at the design and near-surge conditions have been quantified by numerically modelling the open and blocked configuration of the compressors. Upon comparing with experimental results, the numerical spectra are shown to capture the differences between the two configurations at the investigated operating points with reasonable accuracy. Although the casing treatment is generally seen to decrease the overall acoustic emission of the compressor at both operating conditions, increased propagation of tonal content in the direction upstream to the impeller is observed, particularly for design operation. Broadband characteristics in the lower and medium frequency regions usually associated with near-surge operation including ‘whoosh’ noise are observed to be alleviated by the ported shroud casing treatment.
Towards Low-Cost Mechanisms to Enable Restoration of Encrypted Non-Volatile Memories

Since Non-Volatile Memories (NVMs) started entering the mainstream memory/storage market, we must consider how to secure NVM-equipped computing systems. Recent Meltdown and Spectre attacks are a strong evidence that security must be intrinsic to computing systems instead of being added as an afterthought. Processor vendors are taking the first steps and are beginning to build security primitives into commodity processors. One security primitive that is associated with the use of emerging NVMs is memory encryption. Memory encryption, while necessary, is very challenging when used with NVMs because it exacerbates the write endurance problem. Secure architectures use cryptographic metadata that must be persisted and restored to allow secure recovery of data in the event of power-loss. Specifically, encryption counters must be persistent to enable secure and functional recovery of an interrupted system. However, the cost of ensuring and maintaining persistence for these counters can be significant. In this paper, we propose a novel scheme to maintain encryption counters without the need for frequent updates. Our new memory controller design, Osiris, repurposes memory Error-Correction Codes (ECCs) to enable fast restoration and recovery of encryption counters. Since different counter-mode encryption schemes are used in industry and research, we provide a versatile Osiris implementation that improves the performance and write-endurance in different memory encryption schemes. To evaluate our design, we use Gem5 to run eight memory-intensive workloads selected from SPEC2006 and U.S. Department of Energy (DoE) proxy applications, and three computation-intensive graph algorithms from CRONO. Compared to a write-through counter-cache scheme, on average, Osiris can reduce 45.8 percent of the memory writes (increase lifetime by 1.86x), and reduce the performance overhead from 44.7 percent(for write-through) to only 4.49 percent. Furthermore, without the need for backup battery or extra power-supply hold-up time, Osiris performs better than a battery-backed write-back (4.4 versus 5.7 percent overhead) and has less write-traffic (1.8 versus 5.4 percent overhead).
Halophilic responses to a range of salts and their relevance to Mars

This Thesis investigated the survival of salt-tolerant microorganisms in environments where salts other than NaCl are present, with the aim being to shed new light on the martian astrobiological potential of halophiles. Salt tolerant microorganisms, “halophiles”, are often proposed as analogues for potential martian life because, for water to exist on, or near, the present-day martian surface requires it to be highly saline. Furthermore, martian salt deposits are often proposed as locations in which to find evidence of ancient martian life; halophiles can undergo “entombment” within salt crystals for indeterminately long periods of time, and there is evidence that this provides protection from the extremes of the martian environment. Both of these proposals, however, are based upon studies of halophiles in terrestrial environments where NaCl is the dominant salt, whereas the martian environment is dominated by a wide range of salt compositions In this Thesis, Boulby Mine in Yorkshire was studied as its deposits feature a gradual transition from halite (NaCl) to potash (NaCl and KCl in equal concentrations) that might influence the microbial community present. Despite using both culture-independent and culture-dependent techniques, no difference was found in the microbial community across this transition in salt chemistry. It was shown that the NaCl requirement of obligate halophiles, isolated from these deposits, could be lowered by the presence of many other salts (KCl, K2SO4, MgCl2, MgSO4, Na2SO4, CaSO4). Furthermore, with the exception of MgCl2, the presence of these dissolved salts facilitated the entombment of viable cells and improved the UV tolerance of entombed microorganisms. This Thesis, therefore, suggests that the presence of non-NaCl salts in a martian environment could support the growth, entombment and survival of organisms analogous to halophiles.
I/O performance of the Santos Dumont supercomputer

In this article, we study the I/O performance of the Santos Dumont supercomputer, since the gap between processing and data access speeds causes many applications to spend a large portion of their execution on I/O operations. For a large-scale expensive supercomputer, it is essential to ensure applications achieve the best I/O performance to promote efficient usage. We monitor a week of the machine’s activity and present a detailed study on the obtained metrics, aiming at providing an understanding of its workload. From experiences with one numerical simulation, we identified large I/O performance differences between the MPI implementations available to users. We investigated the phenomenon and narrowed it down to collective I/O operations with small request sizes. For these, we concluded that the customized MPI implementation by the machine’s vendor (used by more than 20% of the jobs) presents the worst performance. By investigating the issue, we provide information to help improve future MPI-IO collective write implementations and practical guidelines to help users and steer future system upgrades. Finally, we discuss the challenge of describing applications I/O behavior without depending on information from users. That allows for identifying the application’s I/O bottlenecks and proposing ways of improving its I/O performance. We propose a methodology to do so, and use GROMACS, the application with the largest number of jobs in 2017, as a case study.
Ping-Pong Optimization of User Selection and Beam Allocation for Millimeter Wave Communications

Both millimeter wave (mmWave) communication and massive multiple-input multiple-output (MIMO) are important technologies in the 5G era. To reduce the cost of a mmWave massive MIMO system in practice, hybrid beamforming usually adopted, which however inevitability complicates both user selection and analog beam allocation. To this end, in this paper we jointly optimize user selection and beam allocation under a wideband frequency selective mmWave channel. To be practical, both beam collision and inter-user interference have been taken into account. To tackle the non-convexity of the formulated problem, we propose a ping-pong-like optimization method by using hybrid particle swarm optimization and simulated annealing (HPS). Concretely, the joint optimization problem is divided into two sub-problems and the near-optimal solution is approached via ping-pong iteration optimization. The Metropolis acceptance criterion of simulated annealing algorithm is introduced to overcome the drawback of traditional particle swarm optimization, improving global search capability of HPS algorithm. The simulation results verify the effectiveness and flexibility of the proposed method compared with existing methods.
Thermal Conductivity of Amorphous Materials

Thermal conductivity is one of the most fundamental properties of solid materials. The thermal conductivity of ideal crystal materials has been widely studied over the past hundreds years. On the contrary, for amorphous materials that have valuable applications in flexible electronics, wearable electrics, artificial intelligence chips, thermal protection, advanced detectors, thermoelectrics, and other fields, their thermal properties are relatively rarely reported. Moreover, recent research indicates that the thermal conductivity of amorphous materials is quite different from that of ideal crystal materials. In this article, the authors systematically review the fundamental physical aspects of thermal conductivity in amorphous materials. They discuss the method to distinguish the different heat carriers (propagons, diffusons, and locons) and the relative contribution from them to thermal conductivity. In addition, various influencing factors, such as size, temperature, and interfaces, are addressed, and a series of interesting anomalies are presented. Finally, the authors discuss a number of open problems on thermal conductivity of amorphous materials and a brief summary is provided.
From pixels to spikes : efficient multimodal learning in the presence of domain shift

Computer vision aims to provide computers with a conceptual understanding of images or video by learning a high-level representation. This representation is typically derived from the pixel domain (i.e., RGB channels) for tasks such as image classification or action recognition. In this thesis, we explore how RGB inputs can either be pre-processed or supplemented with other compressed visual modalities, in order to improve the accuracy-complexity tradeoff for various computer vision tasks. Beginning with RGB-domain data only, we propose a multi-level, Voronoi based spatial partitioning of images, which are individually processed by a convolutional neural network (CNN), to improve the scale invariance of the embedding. We combine this with a novel and efficient approach for optimal bit allocation within the quantized cell representations. We evaluate this proposal on the content-based image retrieval task, which constitutes finding similar images in a dataset to a given query. We then move to the more challenging domain of action recognition, where a video sequence is classified according to its constituent action. In this case, we demonstrate how the RGB modality can be supplemented with a ﬂow modality, comprising motion vectors extracted directly from the video codec. The motion vectors (MVs) are used both as input to a CNN and as an activity sensor for providing selective macroblock (MB) decoding of RGB frames instead of full-frame decoding. We independently train two CNNs on RGB and MV correspondences and then fuse their scores during inference, demonstrating faster end-to-end processing and competitive classification accuracy to recent work. In order to explore the use of more efficient sensing modalities, we replace the MV stream with a neuromorphic vision sensing (NVS) stream for action recognition. NVS hardware mimics the biological retina and operates with substantially lower power and at significantly higher sampling rates than conventional active pixel sensing (APS) cameras. Due to the lack of training data in this domain, we generate emulated NVS frames directly from consecutive RGB frames and use these to train a teacher-student framework that additionally leverages on the abundance of optical ﬂow training data. In the final part of this thesis, we introduce a novel unsupervised domain adaptation method for further minimizing the domain shift between emulated (source) and real (target) NVS data domains.