534 research outputs found
Aquatic macroinvertebrate responses to native and non-native predators
Non-native species can profoundly affect native ecosystems through trophic interactions with native species. Native prey may respond differently to non-native versus native predators since they lack prior experience. Here we investigate antipredator responses of two common freshwater macroinvertebrates, Gammarus pulex and Potamopyrgus jenkinsi, to olfactory cues from three predators; sympatric native fish (Gasterosteus aculeatus), sympatric native crayfish (Austropotamobius pallipes), and novel invasive crayfish (Pacifastacus leniusculus). G. pulex responded differently to fish and crayfish; showing enhanced locomotion in response to fish, but a preference for the dark over the light in response to the crayfish. P. jenkinsi showed increased vertical migration in response to all three predator cues relative to controls. These different responses to fish and crayfish are hypothesised to reflect the predatorsâ differing predation types; benthic for crayfish and pelagic for fish. However, we found no difference in response to native versus invasive crayfish, indicating that prey naivetĂ© is unlikely to drive the impacts of invasive crayfish. The Predator Recognition Continuum Hypothesis proposes that benefits of generalisable predator recognition outweigh costs when predators are diverse. Generalised responses of prey as observed here will be adaptive in the presence of an invader, and may reduce novel predatorsâ potential impacts
Fotodegradasi Zat Warna Metanil Yellow Menggunakan Fotokatalis TiO2-Karbon Aktif
Telah dilakukan penelitian untuk mempelajari pengaruh penambahan karbon aktif (KA) pada fotokatalis TiO2 serta aktivitas fotokatalitiknya dalam proses fotodegradasi zat warna metanil yellow. Penelitian diawali dengan pembuatan KA dari tempurung kelapa, kemudian dilakukan modifikasi fotokatalis TiO2âKA. Eksperiman fotodegradasi metanil yellow oleh fotokatalis TiO2âKA dilakukan dengan perbandingan berat TiO2:KA sebesar 9,9:0,1 dan 9,5:0,5 dan konsentrasi metanil yellow 2â50 ppm, serta variasi waktu penyinaran sinar UV selama 1, 2, 3, 4, 5, 19 dan 20 jam. Hasil penelitian menunjukkan bahwa persentase proses fotodegradasi tertinggi diperoleh pada perbandingan berat TiO2:KA (9,9:0,1) dan aktivitas fotodegradasi semakin meningkat seiring dengan bertambahnya waktu penyinaran.A research had been conducted to study the effect of the addition of activated carbon (AC) on TiO2 photocatalyst and its photocatalytic activity in photodegradation process of metanil yellow dye. The research was performed through the preparation of activated carbon from coconut shell and modification of photocatalyst TiO2âAC. Experiment of metanil yellow photodegradation by photocatalyst TiO2âAC was performed at the weight ratio of TiO2:AC of 9,9:0,1 and 9,5:0,5 with the concentrations of metanil yellow of 2â50 ppm, and time variations of UV rays irradiation of 1, 2, 3, 4, 5, 19 and 20 hours. The results showed that the highest percentage of photodegradation process obtained at the weight ratio of TiO2:AC of 9,9:0,1 and the photodegradation activity was increased along with increasing irradiation tim
Issues in teaching to the writing test : preparing students for the TOEFL(R); iBT independent writing task
Students in the Department of International Studies at Doshisha Womenâs College are required to study overseas for one year at a college or university in an English-speaking country. For this reason, their first year is devoted to test preparation. Teaching such test preparation courses forces the instructors to face several issues related to "teaching to the test" such as effectiveness and the relationship to usual language teaching. These issues have been discussed in the literature to some extent but only a few studies address them in a specific context. This paper examines a course designed to prepare students for the independent writing task of the TOEFL iBT; it presents a detailed description of how the course is taught based on the reflections of four instructors, focusing on three issues related to teaching to the test: teaching writing as opposed to teaching to the prompt; the effect of the test rubric and the holistic scoring policy on teaching; and the use of textbooks. We conclude that teaching to the test is compatible with sound instructional practice.è«æ (Article
A novel Markov logic rule induction strategy for characterizing sports video footage
The grounding of high-level semantic concepts is a key requirement of video annotation systems. Rule induction can thus constitute an invaluable intermediate step in characterizing protocol-governed domains, such as broadcast sports footage. We here set out a novel âclause grammar templateâ approach to the problem of rule-induction in video footage of court games that employs a second-order meta grammar for Markov Logic Network construction. The aim is to build an adaptive system for sports video annotation capable, in principle, both of learning ab initio and also adaptively transferring learning between distinct rule domains. The method is tested with respect to both a simulated game predicate generator and also real data derived from tennis footage via computer-vision based approaches including HOG3D based player-action classification, Hough-transform based court detection, and graph-theoretic ball-tracking. Experiments demonstrate that the method exhibits both error resilience and learning transfer in the court domain context. Moreover the clause template approach naturally generalizes to any suitably-constrained, protocol-governed video domain characterized by feature noise or detector error
Radiofrequency-assisted liver resection versus clamp-crush liver resection: protocol for an updated meta-analysis and systematic review
Background: Malignancy of the liver has historically meant a poor prognosis and remains the second most common cause of cancer-related deaths globally. Traditionally, hepatectomy has utilized the clamp-crush technique; however, this is associated with high incidence of postoperative complications. Many novel techniques have been developedâradiofrequency ablation and transarterial chemoembolization; however, these are not applicable to numerous cases. Clamp-crush liver resection (CCLR) remains the gold standard. Radiofrequency-assisted liver resection (RFLR) is a technique that aims to reduce mortality through bloodless liver resection. A systematic review was previously performed on RFLR but the results neither recommended nor refuted the use of RFLR owing to the lack of sufficient evidence from well-designed randomized controlled trials (RCTs) at the time. Objective: The aim of the study is the meta-analysis and systematic review of recent studies comparing RFLR against CCLR. Methods: Articles comparing RFLR and CCLR that were published from 2014 until 2019 will be reviewed and relevant data will be extracted and statistically analyzed through Review Manager 5 (by the Cochrane Collaboration) together with the results of the previous meta-analysis. Results: Data collection is currently underway, with papers being screened. We hope to publish the results by the end of 2019. Conclusions: Given the high mortality rates currently associated with liver resection, it is imperative that novel surgical techniques are undertaken and investigated so we can improve best practice guidance and outcomes. International Registered Report Identifier (IRRID): DERR1-10.2196/1343
Automatic annotation of tennis games: an integration of audio, vision, and learning
Fully automatic annotation of tennis game using broadcast video is a task with a great potential but with enormous challenges. In this paper we describe our approach to this task, which integrates computer vision, machine listening, and machine learning. At the low level processing, we improve upon our previously proposed state-of-the-art tennis ball tracking algorithm and employ audio signal processing techniques to detect key events and construct features for classifying the events. At high level analysis, we model event classification as a sequence labelling problem, and investigate four machine learning techniques using simulated event sequences. Finally, we evaluate our proposed approach on three real world tennis games, and discuss the interplay between audio, vision and learning. To the best of our knowledge, our system is the only one that can annotate tennis game at such a detailed level
Gaelic on Skye: Older speakers' identity in a language-shift situation
Language Use in Past and Presen
Gaelic language erosion and revitalization on the Isle of Skye, Scotland.
This paper analyzes the language loss of three generations of a Gaelic-speaking family located on the Isle of Skye, Scotland. Participants' linguistic skills were assessed via language ability tests. We focused on plurals, passives, and tense, and we examined synthetic forms. The results confirmed that erosion is occurring in all areas investigated; in particular, the synthetic nature of Gaelic causes problems for younger generation speakers. This suggests weak language transmission through the generations as well as the dominance of English in the community. Through an interview with an expert informant, we also explored the implications of Gaelic education for the Gaelicspeaking community on Skye. Revitalization efforts are currently underway, but despite maintenance efforts such as Gaelic Medium Education (GME), English remains the language of the schoolchildren as well as the community at large. The authors feel that a concerted community revitalization effort is needed in congruence with the application of GME. Maintenance efforts should be directed towards sponsoring Gaelic-speaking community events so that GME students have the opportunity to speak Gaelic outside the classroom as well as experience the viability of the language for communication in different domains.Historical sociolinguistics LUC
Domain anomaly detection in machine perception: a system architecture and taxonomy
We address the problem of anomaly detection in machine perception. The concept of domain anomaly is introduced as distinct from the conventional notion of anomaly used in the literature. We propose a unified framework for anomaly detection which exposes the multifacetted nature of anomalies and suggest effective mechanisms for identifying and distinguishing each facet as instruments for domain anomaly detection. The framework draws on the Bayesian probabilistic reasoning apparatus which clearly defines concepts such as outlier, noise, distribution drift, novelty detection (object, object primitive), rare events, and unexpected events. Based on these concepts we provide a taxonomy of domain anomaly events. One of the mechanisms helping to pinpoint the nature of anomaly is based on detecting incongruence between contextual and noncontextual sensor(y) data interpretation. The proposed methodology has wide applicability. It underpins in a unified way the anomaly detection applications found in the literature
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