46 research outputs found

    Head Mounted Display Interaction Evaluation: Manipulating Virtual Objects in Augmented Reality

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    Augmented Reality (AR) is getting close to real use cases,which is driving the creation of innovative applications and the unprecedented growth of Head-Mounted Display (HMD) devices in consumer availability. However, at present there is a lack of guidelines, common form factors and standard interaction paradigms between devices, which has resulted in each HMD manufacturer creating their own specifications. This paper presents the first experimental evaluation of two AR HMDs evaluating their interaction paradigms, namely we used the HoloLens v1 (metaphoric interaction) and Meta2 (isomorphic interaction). We report on precision, interactivity and usability metrics in an object manipulation task-based user study. 20 participants took part in this study and significant differences were found between interaction paradigms of the devices for move tasks, where the isomorphic mapped interaction outperformed the metaphoric mapped interaction in both time to completion and accuracy, while the contrary was found for the resize task. From an interaction perspective, the isomorphic mapped interaction (using the Meta2) was perceived as more natural and usable with a significantly higher usability score and a significantly lower task-load index. However, when task accuracy and time to completion is key mixed interaction paradigms need to be considered

    A novel widespread cryptic species and phylogeographic patterns within several giant clam species (Cardiidae: Tridacna) from the Indo-Pacific Ocean

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    Giant clams (genus Tridacna) are iconic coral reef animals of the Indian and Pacific Oceans, easily recognizable by their massive shells and vibrantly colored mantle tissue. Most Tridacna species are listed by CITES and the IUCN Redlist, as their populations have been extensively harvested and depleted in many regions. Here, we survey Tridacna crocea and Tridacna maxima from the eastern Indian and western Pacific Oceans for mitochondrial (COI and 16S) and nuclear (ITS) sequence variation and consolidate these data with previous published results using phylogenetic analyses. We find deep intraspecific differentiation within both T. crocea and T. maxima. In T. crocea we describe a previously undocumented phylogeographic division to the east of Cenderawasih Bay (northwest New Guinea), whereas for T. maxima the previously described, distinctive lineage of Cenderawasih Bay can be seen to also typify western Pacific populations. Furthermore, we find an undescribed, monophyletic group that is evolutionarily distinct from named Tridacna species at both mitochondrial and nuclear loci. This cryptic taxon is geographically widespread with a range extent that minimally includes much of the central Indo-Pacific region. Our results reinforce the emerging paradigm that cryptic species are common among marine invertebrates, even for conspicuous and culturally significant taxa. Additionally, our results add to identified locations of genetic differentiation across the central Indo-Pacific and highlight how phylogeographic patterns may differ even between closely related and co-distributed species

    Development of a dosimetric tool to measure human UVA exposures

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    [Introduction]: Humans in their day-to-day lives are exposed to solar ultraviolet (UV) radiation. These solar UV exposures can be separated into UVB exposures (280nm to 320nm) and UVA exposures (320 to 400nm). Most acute responses of humans to UV exposure occur as a result of UVB exposures, as these wavelengths are highly sensitive in creating a human biological response. This however does not result in UVA radiation not having an impact on human UV exposures and health. UVA can cause erythema in human skin, yet, the exposures required to create such a response is much larger than UVB radiation. UVA radiation penetrates much deeper into human skin tissue than UVB, resulting in impacts that are not as acute, taking many years to manifest. UVA exposures are associated with wrinkling, loss of skin elasticity, ocular disorders and it has been implicated in the development of skin cancers

    Causes and Measures of Conflicts among Gang Inmates in Dipolog and Dapitan City Jails

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    Current jail management models strictly prohibit inmates from assisting with jail administration or governance. This is feasible in developed countries where governments can provide adequate resources, security, and personnel. It is not, however, realistic in developing countries like the Philippines, which is characterized by poverty, corruption, and under resourcing of correctional facilities. In such circumstances, inmate leaders tend to share governance with jail administrators. Gang leaders help in maintaining peace and order in jail. This paper explored the causes of conflicts among gang members in Dipolog and Dapitan City jails and identified preventive measures to eliminate threats caused by the conflicts. There were two groups of respondents who were considered in the study. The first group are the gang inmates composed of 188 who answered the survey instrument intended to determine reasons of joining gang and the different causes of conflicts. The second group was the jail personnel who answered the survey instrument on the measures to prevent the conflicts. study revealed that conflicts usually occur during the start and playoff time of National Basketball Association (NBA) and Philippine Basketball Association (PBA) because it is this time that gambling is usually occurred. Conflicts were mainly caused by unpaid debts, theft and overcrowding. Admonition and forfeiture of good conduct time, close confinement and reduction of visiting hours were among the most common measures to discourage conflict. It is recommended to prohibit gambling of any sort. Conduct more physical activities to make the inmates busy

    A new PCR-based approach indicates the range of Clonorchis sinensis now extends to central Thailand

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    Differentiation of the fish-borne trematodes belonging to the Opisthorchiidae, Heterophyidae and Lecithodendriidae is important from a clinical and epidemiological perspective, yet it is impossible to do using conventional coprological techniques, as the eggs are morphologically similar. Epidemiological investigation therefore currently relies on morphological examination of adult worms following expulsion chemotherapy. A PCR test capable of amplifying a segment of the internal transcribed spacer region of ribosomal DNA for the opisthorchiid and heterophyid flukes eggs taken directly from faeces was developed and evaluated in a rural community in central Thailand. The lowest quantity of DNA that could be amplified from individual adults of Opisthorchis viverrini, Clonorchis sinensis and Haplorchis taichui was estimated at 0.6 pg, 0.8 pg and 3 pg, respectively. The PCR was capable of detecting mixed infection with the aforementioned species of flukes under experimental conditions. A total of 11.6% of individuals in rural communities in Sanamchaikaet district, central Thailand, were positive for ‘Opisthorchis-like’ eggs in their faeces using conventional parasitological detection techniques. In comparison to microscopy, the PCR yielded a sensitivity and specificity of 71.0% and 76.7%, respectively. Analysis of the microscopy-positive PCR products revealed 64% and 23% of individuals to be infected with O. viverrini and C. sinensis, respectively. The remaining 13% (three individuals) were identified as eggs of Didymozoidae, presumably being passed mechanically in the faeces following the ingestion of infected fishes. An immediate finding of this study is the identification and first report of a C. sinensis–endemic community in central Thailand. This extends the known range of this liver fluke in Southeast Asia. The PCR developed herein provides an important tool for the specific identification of liver and intestinal fluke species for future epidemiological surveys
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