No abstract

SUMMARY360 videos have recently become a popular virtual reality content type. However, a good quality metric for 360 videos is still an open issue. In this work, our goal is to identify appropriate objective quality metrics for 360 video communications. Especially, fourteen objective quality measures at different processing phases are considered. Also, a subjective test is conducted in this study. The relationship between objective quality and subjective quality is investigated. It is found that most of the PSNR-related quality measures are well correlated with subjective quality. However, for evaluating video quality across different contents, a content-based quality metric is needed. key words: 360 video, objective quality, subjective quality, video processing

A new, critically endangered species of softshell turtle, Pelodiscusvariegatussp. n. is described from north-central Vietnam and Hainan Island, China, distinguished by a unique set of genetic and morphological traits from all other congeners (P.axenaria, P.maackii, P.parviformis, P.sinensis, and unnamed genetic lineages). Morphologically, P.variegatus is characterized, among others, by its strong ventral ornamentation in all age classes.

The Crocodile lizard Shinisaurus crocodilurus is a popular reptile species in the pet trade and has been regularly kept in terrariums by hobbyists since the 1980s. Recent integrative taxonomic research revealed the Chinese representatives to be morphologically, genetically and ecologically distinct from Vietnamese populations, which occur in alarmingly low population sizes. All extant populations are threatened by habitat destruction and poaching for the pet trade. Thus, it will be crucial to manage the Vietnamese and Chinese subspecies separately as different conservation units, both to maintain their genetic integrity and to adjust appropriate husbandry conditions in the frame of ex situ conservation programmes. For this reason, we provide a topical review of microhabitat use of the newly described subspecies from Vietnam – the Vietnamese crocodile lizard Shinisaurus crocodilurus vietnamensis – based on recent field work as well as husbandry experiences at the Me Linh Station for Biodiversity in North Vietnam. We further compare our new findings with the data available for the nominate subspecies from China. Based on our current knowledge, we update existing minimum husbandry requirements in Germany and elaborate different husbandry parameters for both subspecies. Furthermore, we introduce new husbandry protocols and facility designs for the Vietnamese subspecies both at Me Linh Station for Biodiversity and at Cologne Zoo, Germany.

The current decline in global biodiversity is most evident in amphibians with 41% percent of all species worldwide classified as threatened with extinction. Hence, a major challenge in amphibian conservation is the high number of threatened species, leading to a common approach of identifying priority species and regions for conservation efforts. As a part of one of 36 globally designated biodiversity hotspots, Vietnam is considered to be of particular importance for conservation action. To improve amphibian conservation in Vietnam, this study provides an updated species list and assesses their threat status by compiling data from a variety of sources. Furthermore, a Zoological Information Management System (ZIMS) analysis was conducted to determine the representation of extant amphibians from Vietnam in zoos worldwide. The batrachofauna of Vietnam is characterized by a high level of species richness and local endemism as well as a high rate of new discoveries, with more than half of the endemic species reported exclusively from their type locality, making them especially vulnerable to extinction. Up to 18% of all amphibians extant in Vietnam and 28% of endemic species are classified as threatened with extinction by the IUCN. In many cases, the IUCN Red List status is either missing or outdated, highlighting the urgent need of action. Around 14% of endemic amphibian species have been recorded exclusively from unprotected areas, suggesting prioritization for further research and conservation measures. The continuing decline in many species remains an unresolved problem. As a guide for future research and conservation measures, a list of the top 57 species was compiled. In addition, according to the ZIMS analysis, only 8% of threatened and 3% of endemic amphibian taxa from Vietnam are currently kept in zoos worldwide, and a richness analysis revealed that the highest density of husbandries is found in Europe and North America. To achieve maximum outcome for the conservation of threatened species, this study recommends a general shift by zoos towards maintaining species in greater need of captive assurance populations and breeding programs to support integrative strategies that combine in situ and ex situ conservation efforts following the IUCN’s One Plan Approach.