The evolutionary relationship between the domestic bactrian camel and the extant wild two-humped camel and the factual origin of the domestic bactrian camel remain elusive. We determined the sequence of mitochondrial cytb gene from 21 camel samples, including 18 domestic camels (three Camelus bactrianus xinjiang, three Camelus bactrianus sunite, three Camelus bactrianus alashan, three Camelus bactrianus red, three Camelus bactrianus brown and three Camelus bactrianus normal) and three wild camels (Camelus bactrianus ferus). Our phylogenetic analyses revealed that the extant wild two-humped camel may not share a common ancestor with the domestic bactrian camel and they are not the same subspecies at least in their maternal origins. Molecular clock analysis based on complete mitochondrial genome sequences indicated that the sub-speciation of the two lineages had begun in the early Pleistocene, about 0.7 million years ago. According to the archaeological dating of the earliest known two-humped camel domestication (5000–6000 years ago), we could conclude that the extant wild camel is a separate lineage but not the direct progenitor of the domestic bactrian camel. Further phylogenetic analysis suggested that the bactrian camel appeared monophyletic in evolutionary origin and that the domestic bactrian camel could originate from a single wild population. The data presented here show how conservation strategies should be implemented to protect the critically endangered wild camel, as it is the last extant form of the wild tribe Camelina.

A novel and high-performance four-element ultra-wideband (UWB) multiple-input multipleoutput (MIMO) antenna is proposed in the paper. The proposed antenna is designed by using a novel integration technology of the symmetric layout, orthogonal structure, four-directional staircase-shaped decoupling, and multi-slit and multi-slot techniques. The mutual couplings among the antenna elements are significantly reduced by introducing the symmetric orthogonal and separated four-directional staircaseshaped structure. Furthermore, the antenna size is effectively miniaturized, and its impedance bandwidth is broadened by using a two-sided symmetric layout, partial and defected ground structure, the decoupling structure, and multi-slot and multi-slit techniques. Therefore, the antenna has the low-profile structure and a small dimension of 39mm×39mm×1.6mm. Moreover, the proposed antenna achieves triple band-notched characteristics by embedding different type slots and slits on the square radiating elements, default ground structure, and the decoupling structure, respectively. As a result, the antenna obtains the wider bandwidth of 2.30-13.75 GHz with the notched bands of 3.25-3.75 GHz, 5.08-5.90 GHz, and 7.06-7.95 GHz. The three notched bands are good in agreement with the existing interference bands of WiMAX (3.3-3.7 GHz), , and X-band (7.1-7.9 GHz), respectively. In addition, the proposed antenna also has a lower mutual coupling (<−22dB), lower envelop correlation coefficient (ECC<0.02, except for the three notched bands), high multiplexing efficiency (η mux >−3.0dB), stable gain, and quasi-omnidirectional radiation patterns at the entire impedance bandwidth. Therefore, a good tradeoff of the performance is obtained for the proposed antenna. The proposed antenna can be a good candidate for UWB-MIMO wireless communication applications, and especially for portable UWB-MIMO systems.INDEX TERMS UWB-MIMO antenna, symmetric orthogonal structure, multi-slot-multi-slit, high isolation, triple band-notched characteristics. I. INTRODUCTION

No abstract

Detection limit of sodium fluorescein in plant cells can reach 0.14 μg cm−3 based on LRET from UCNPs to SF.

The use of light‐emitting diodes (LED) has increased rapidly in Taiwan, because their energy losses are lower than traditional illuminants. Scrap is produced in the manufacturing process for LEDs, which contains valuable metals (i.e., Ga) and harmful component (i.e., As). For sustainable environmental reasons, this study develops a recycling technique for GaAs scrap. The GaAs scrap was firstly ground and sieved to pass 100 mesh sieve. The powder sample was leached, using 1.5 N nitric acid at 40°C for 1.5 h, and the dissolution of Ga and As was close to 100%. Sodium sulfide solution was added into the leachate as a precipitating agent and As was selectively precipitated from the solution. In the optimal conditions, using a 0.1 M of sodium sulfide and a flow rate of 5 mL/min, the precipitation percentages of As and Ga were 98.5 and 1.5%, respectively. The purified Ga solution was recovered, and the As was concentrated in the sediment. The precipitate was examined using X‐ray diffraction and the major phase was identified as As2O3 which can be stabilized using the ferrite process or used as a raw material in a related industry. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 471–475, 2015