Following habitat fragmentation, the remnant faunal community will undergo a period of species loss or 'relaxation.' Theory predicts that species with particular life-history traits, such as a small population size, small geographical range, low fecundity and large body size, should be more vulnerable to fragmentation. In this study, we investigated the relationships between the above life-history traits and the fragmentation vulnerability index (the number of islands occupied) of five lizard species inhabiting recently isolated land-bridge islands in the Thousand Island Lake, China. Data on life-history traits were collected from field surveys (population density) and from the literature (body size, clutch size and geographical range size). The species-area relationships for lizards sampled from the mainland versus on the islands differed significantly (i.e. the number of species inhabiting islands was decreased relative to similar-sized areas on the mainland), indicating that species extinction has occurred on all of the study islands following isolation. For the fragmentation vulnerability index, model selection based on Akaike's information criterion identified natural density at mainland sites as the best correlate of vulnerability to fragmentation, supporting the hypothesis that rare species are most vulnerable to local extinction and will be lost first from fragmented landscapes. In contrast, there was little evidence for an effect of lizards' snout-vent length, clutch size or geographical range size on fragmentation vulnerability. Identification of species traits that render some species more vulnerable to fragmentation than others has important implications for conservation and can be used to aid direct management efforts.

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Due to their unique properties, such as good biocompatibility, excellent conductivity, effective catalysis, high density, and high surface-to-volume ratio, gold nanoparticles (AuNPs) are widely used in the field of bioassay. Mainly, AuNPs used in optical biosensors have been described in some reviews. In this review, we highlight recent advances in AuNP-based non-optical bioassays, including piezoelectric biosensor, electrochemical biosensor, and inductively coupled plasma mass spectrometry (ICP-MS) bio-detection. Some representative examples are presented to illustrate the effect of AuNPs in non-optical bioassay and the mechanisms of AuNPs in improving detection performances are described. Finally, the review summarizes the future prospects of AuNPs in non-optical biosensors.

We report a compact diode-laser pumped Nd:GdVO(4) laser with stable dual-wavelength output at 1063 nm and 1065 nm simultaneously. Two types of resonant cavity configurations were presented to support the stable dual-wavelength operation of the laser. Using a polarization beam splitter(PBS) included T-shaped cavity, we obtained a total power output over 5 W in two orthogonal polarized beam directions with 4 W in sigma polarization (1065.5 nm) and 1 W in pi polarization (1063.1 nm). By combining a half-wave-plate with the PBS in the laser cavity, a new configuration favoring one beam direction dual-wavelength output with same polarization direction was realized. A phenomenon of further line splitting was observed in both 1065 nm and 1063 nm.

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Abstract:We report experimental results on an all-fiberized linearly polarized single-mode pulse Yb-doped fiber laser/amplifier working at 1064 nm. Using a fiberized acousto-optic Qswitched ytterbium fiber laser as the seed source, a double-clad polarization-maintaining fiber as the gain medium, a (6+1)×1 multimode pump combiner to input the seed signal and the pump power, an Yb fiber master oscillator power amplifier (MOPA) is demonstrated. It delivers a linearly polarized pulsed laser output working at 1064 nm with an average power of 30 W, a repetition rate of 40 kHz, a pulse duration time about 30 ns, a polarization extinction ratio greater than 10 dB, and a beam quality factor (M 2 ) of 1.36. Our experiments were pump-power limited and considerable scope remains for further power-scaling of such fiber MOPA using this approach. [5]. High power single-mode pulsed fiber laser with multi10ns pulses can find a wide variety of applications in material processing, laser radar, remote sensing and nonlinear frequency conversion, etc. Its advantages such as good beam quality, high efficiency, excellent heat dissipation capability, and compactness make the pulsed Yb-doped fiber lasers and/or amplifiers superior to conventional bulk solid-state lasers and gas lasers [6]. As many applications require polarization maintain (PM) operation, there is a great interest in making these pulsed fiber lasers and amplifiers linearly polarized [7,8].By applying double-clad fibers, output power of continuous-wave fiber lasers has approached kW-regime [9]. However, the power-scaling of pulsed fiber lasers is much more difficult, because of strong deleterious nonlinear effects within the fiber, such as stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS), which usually constitute the main performance limitation of the pulsed fiber laser systems [10,11]. Since the thresholds of SBS and SRS in PM fibers are much lower than in non-PM fibers [12], the operation of linearly polarized pulsed fiber lasers and amplifiers is more challenging. Several linearly polarized pulse fiber lasers and amplifiers have recently been reported [13,14]. By adjusting the power and repetition rate of the seed to suppress the nonlinear phenomenon, an acousto-optic(AO) Q-switched Nd:YVO4 laser seeded ytterbium fiber master oscillator power amplifier (MOPA) achieved linearly polarized output power of 50 W [15]. Using a pulse shaping technology, some authors of this paper also demonstrated a diode seeded high power linearly-polarized Yb fiber MOPA with

The determination of nanoparticle (NP) stability and degradation in vivo is essential for the accurate evaluation of NP biodistribution in medical applications and for understanding their toxicological effects. Such determination is particularly challenging because NPs are extremely difficult to detect and quantify once distributed in a biological system. Radiolabelling with positron or gamma emitters and subsequent imaging studies using positron emission tomography (PET) or single-photon emission computerised tomography (SPECT) are some of the few valid alternatives. However, NPs that degrade or radionuclides that detach or are released from the NPs can cause artefact. Here, submicron-sized poly(lactide-coglycolide) nanoparticles (PLGA-NPs) stabilised with bovine serum albumin (BSA) were dual radiolabelled using gamma emitters with different energy spectra incorporated into the core and coating. To label the core, 111 In-doped iron oxide NPs were encapsulated inside PLGA-NPs during NP preparation, and the BSA coating was labelled by electrophilic substitution using 125 I. After intravenous administration into rats, energy-discriminant SPECT resolved each radioisotope independently. Imaging revealed different fates for the core and coating, with a fraction of the two radionuclides co-localising in the liver and lungs for long periods of time after administration, suggesting that NPs are stable in these organs. Organ harvesting followed by gamma counting corroborated the SPECT results. The general methodology reported here represents an excellent alternative for visualising the degradation process of multi-labelled NPs in vivo and can be extended to a wide range of engineered NPs. 20009,