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Research on island biotas has greatly contributed to the development of modern evolutionary and biogeographic theories. Until now, most studies have suggested that continental islands received their biotas directly from the adjacent mainland. However, only a few studies have indicated that species on continental islands might originate from other distantly non-adjacent regions. Here, we used the hill partridges (genus Arborophila ) that are widely distributed in the southwest and southeast China mainland, Indochina, Hainan and Taiwan islands to test whether species on continental islands might originate from distant regions rather than the adjacent mainland. Based on molecular phylogenies inferred from three mitochondrial fragments and three nuclear introns, together with ancestral area reconstruction, we found that the ancestors of the endemic Hainan and Taiwan partridges ( A. ardens and A. crudigularis ) likely originated from Indochina, rather than the nearby southeast China mainland. The divergence time estimates demonstrate that their ancestors likely colonized Hainan and Taiwan islands using the long exposed continental shelf between Indochina, Hainan and Taiwan islands during glacial periods, which had not been demonstrated before. Thus, integrating distribution data with phylogenetic information can shed new lights on the historical biogeography of continental islands and surrounding mainland regions. [ABSTRACT FROM AUTHOR]

Although tropical and subtropical Asia harbour a high level of species diversity, their species richness can be underestimated because species which are in fact distinct have not been separately identified. In this study, we delimit Bambusicola thoracica into two full species, the Chinese bamboo partridge ( B. thoracica) in continental Asia and the Taiwanese bamboo partridge ( B. sonorivox) on the island of Taiwan, using coalescent-based multilocus division and diagnosable vocalization patterns. Isolation-with-migration analysis indicated that the two bamboo partridges diverged approximately 1.8 million years ago, with gene flow present most probably during the early stages of their divergence. This conclusion supports the hypothesis that diverging lowland lineages spread across the Asian mainland, and continental islands have more opportunities for secondary contact than highland ones when the sea level was low. Our results imply that conservation of biodiversity in tropical and subtropical Asia could be hindered by overlooking numerous 'hidden' species and highlight the importance of re-examining the taxonomic statuses of species in this region traditionally defined as polytypic. [ABSTRACT FROM AUTHOR]

In this paper, we present a new algorithm for clustering proximity-relation matrix that does not require the transitivity property. The proposed algorithm is first inspired by the idea of Yang and Wu [16] then turned into a self-organizing process that is built upon the intuition behind clustering. At the end of the process subjects belonging to be the same cluster should converge to the same point, which represents the cluster center. However, the performance of Yang and Wu's algorithm depends on parameter selection. In this paper, we use the partition entropy (PE) index to choose it. Numerical result illustrates that the proposed method does not only solve the parameter selection problem but also obtains an optimal clustering result. Finally, we apply the proposed algorithm to three applications. One is to evaluate the performance of higher education in Taiwan, another is machine–parts grouping in cellular manufacturing systems, and the other is to cluster probability density functions. [ABSTRACT FROM PUBLISHER]

Hospitality exchange tourism is a new type of niche tourism, which is highly dependent on the Internet. Through participating in global hospitality exchange networks, such as CouchSurfing, tourists can meet local people who are willing to offer free accommodation, and hosts can also meet people around the world by hosting them. CouchSurfing works as a system of reciprocity, in which hospitality as well as cultures is exchanged between hosts and surfers. Through hospitality sharing and cross-cultural interactions, a global community with diverse cultures is envisaged in CouchSurfing. Although CouchSurfing is global in its scope, it is locally practiced in different ways by different cultures. The meaning of CouchSurfing is negotiated by surfers and hosts who both participate in it, and the reciprocal system of CouchSurfing seems to be more complicated when different cultures are involved. Based on Taiwanese experiences of CouchSurfing, this study introduces a non-western perspective on CouchSurfing and has a dialogue with prior research about CouchSurfing that has tended to focus on western experiences. Qualitative methods, including participatory observation and qualitative interviews, are adopted in this study to explore how CouchSurfing is practiced in non-western society. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs), previously commonly used as flame retardants, should be monitored in the environment since some are listed as persistent organic pollutants. A contaminated site near a northern Taiwan factory using decabrominated diphenyl ether (deca-BDE) was identified based on a vegetable PBDEs monitoring project in 2013. The subsequent spatial and temporal survey of that contaminated site shows the contamination ingredients in soils were close to ones used by the factory, indicating that contamination was from the factory, possibly through an exhaust vent. The average concentration of deca-BDE in the main contaminated soil was 615 μg/kg d. w. (dry weight) soil in 2015, slightly decreasing to 604 μg/kg d. w. soil in 2016, increasing to 844 μg/kg d. w. soil in 2017, and then slightly decreasing to 670 μg/kg d. w. soil in 2018. The slight change of deca-BDE and the minor change in low brominated congener level indicate a low degradation rate. The contamination of peripheral sites was around 5000 μg/kg d. w. soil for one PBDEs sampling site that was higher than those around or within the main contaminated farm, indicating serious pollution. Concentrations of PBDEs in different soil depths show that depth 2–15 cm accounted for the greatest PBDEs accumulation, indicating that deca-BDE pollution had been present over time and transported into deeper soil. There can be PBDEs uptake by crops consumed by humans, as shown in our previous studies, so continuous monitoring of PBDEs in this site is important and treatments should be established urgently. Deca-BDE concentration ranging from 140 μg/kg to 5500 μg/kg. Image 1 • PBDEs heavily polluted soil in a Taiwan farm was found by the vegetable inspection. • Commercial deca-BDE used by a factory is the source of the contamination. • Temporal and spatial surveys showed little degradation and spreading of deca-BDE. • Vertical distribution showed leaching of deca-BDE into deeper soil. • Plant uptake of PBDE from soil could cause a crop safety and human health issues. [ABSTRACT FROM AUTHOR]

Background and Purpose: Fragile X syndrome (FXS) is the most common form of hereditary mental retardation. Early diagnosis of the disease may lead to better prognosis for children who participate in early intervention programs. This study attempted to evaluate whether screening newborn boys with simple polymerase chain reaction (PCR) assay could be an effective approach for detection of mutation carriers and FXS, a process that may also facilitate detection of young carrier mothers., Methods: Filter paper blood spot samples of 4843 newborn boys were collected from five hospitals in southern Taiwan. They were tested with a simple non-radioactive PCR for the presence of FMR1 gene mutation by determining the number of FMR1 CGG repeats. By this method, the examined sample can be reliably classified as normal (<40), intermediate (40-54), and mutant group (> 54), according to the number of CGG repeats., Results: The FMR1 CGC repeat number of all but four samples was below 54, with 90 samples (1.8%) between 40 and 54 (the intermediate range). Two of the four abnormal samples were carriers of the premutation. The other two failed repeatedly in PCR amplification for the FMR1 gene, but not for the control K-ras gene. Hence, these samples seemed to be candidate carriers of large premutation or even full mutation, indicating the need for confirmation with standard Southern blot analysis., Conclusions: This study demonstrated that a simple PCR combined with blood spot sampling is effective and feasible for large-scale screening of newborn boys for fragile X carrier status. The relatively low carrier rate in this population suggests that the cost-effectiveness of implementation of such screening on a population-wide basis would be lower than in the Jewish and Caucasian populations.