The Large sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio (SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra (1 061 918 entries), A-type stars (100 073 entries), and M-type stars (121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided.

A series of novel amphiphilic triblock copolymers of poly(ethyl ethylene phosphate) and poly(-caprolactone) (PEEP-PCL-PEEP) with various PEEP and PCL block lengths were synthesized and characterized. These triblock copolymers formed micelles composed of a hydrophobic core of poly(-caprolactone) (PCL) and a hydrophilic shell of poly(ethyl ethylene phosphate) (PEEP) in aqueous solution. The micelle morphology was spherical, determined by transmission electron microscopy. It was found that the size and critical micelle concentration values of the micelles depended on both hydrophobic PCL block length and PEEP hydrophilic block length. The in vitro degradation characteristics of the triblock copolymers were investigated in micellar form, showing that these copolymers were completely biodegradable under enzymatic catalysis of Pseudomonas lipase and phosphodiesterase I. These triblock copolymers were used for paclitaxel (PTX) encapsulation to demonstrate the potential in drug delivery. PTX was successfully loaded into the micelles, and the in vitro release profile was found to be correlative to the polymer composition. These biodegradable triblock copolymer micelles are potential as novel carriers for hydrophobic drug delivery.

We report on novel type of responsive double hydrophilic block copolymer (DHBC)-based multifunctional chemosensors to Hg(2+) ions, pH, and temperatures and investigate the effects of thermo-induced micellization on the detection sensitivity. Well-defined DHBCs bearing rhodamine B-based Hg(2+)-reactive moieties (RhBHA) in the thermo-responsive block, poly(ethylene oxide)-b-poly(N-isopropylacrylamide-co-RhBHA) (PEO-b-P(NIPAM-co-RhBHA)), were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Nonfluorescent RhBHA moieties are subjected to selective ring-opening reaction upon addition of Hg(2+) ions or lowering solution pH, producing highly fluorescent acyclic species. Thus, at room temperature PEO-b-P(NIPAM-co-RhBHA) DHBCs can serve as water-soluble multifunctional and efficient fluorescent chemosensors to Hg(2+) ions and pH. Upon heating above the lower critical solution temperature (approximately 36 degrees C) of the PNIPAM block, they self-assemble into micelles possessing P(NIPAM-co-RhBHA) cores and well-solvated PEO coronas, which were fully characterized by dynamic and static laser light scattering. It was found that the detection sensitivity to Hg(2+) ions and pH could be dramatically improved at elevated temperatures due to fluorescence enhancement of RhBHA residues in the acyclic form, which were embedded within hydrophobic cores of thermo-induced micellar aggregates. This work represents a proof-of-concept example of responsive DHBC-based multifunctional fluorescent chemosensors for the highly efficient detection of Hg(2+) ions, pH, and temperatures with tunable detection sensitivity. Compared to reaction-based small molecule Hg(2+) probes in previous literature reports, the integration of stimuli-responsive block copolymers with well-developed small molecule-based selective sensing moieties in the current study are expected to exhibit preferred advantages including enhanced detection sensitivity, water dispersibility, biocompatibility, facile incorporation into devices, and the ability of further functionalization for targeted imaging and detection.

We report on the synthesis and self-assembly of well-defined coil−rod double hydrophilic diblock copolymer with pH- and thermo-responsive asymmetric centipede-shaped polymer brush as the rod segment via a combination of atom transfer radical polymerization (ATRP) and click chemistry (Schemes and ). At first, poly(ethylene oxide)-b-poly(glycidyl methacrylate), PEO-b-PGMA, was prepared by ATRP using PEO-based macroinitiator. The ring-opening of pendent epoxide moieties in PEO-b-PGMA with NaN3 followed by esterification with 2-bromoisobutyryl bromide afforded multifunctional PEO-b-[PGMA-(N 3)(Br)] bearing one azide and one bromine moieties on each monomer repeating unit of PGMA. The subsequent ATRP of 2-(2-methoxyethoxy)ethyl methacrylate (MEO2MA) using PEO-b-[PGMA-(N 3)(Br)] as the macroinitiator yielded PEO-b-[PGMA-g-(N 3)(PMEO2MA)] coil−brush diblock copolymer possessing one residual azide moiety at each grafting site. Finally, the target coil−rod diblock copolymer with asymmetric centipede-shaped polymer brush as the rod segment, PEO-b-[PGMA-g-(PDEA)(PMEO2MA)], was obtained via the click reaction of PEO-b-[PGMA-g-(N 3)(PMEO2MA)] with an excess of alkynyl-terminated poly(2-(diethylamino)ethyl methacrylate) (alkynyl-PDEA). All the intermediate and final products were characterized by 1H NMR, Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). Atomic force microscopy (AFM) analysis revealed that PEO-b-[PGMA-g-(PDEA)(PMEO2MA)] coil−rod diblock unimer chains adopt a wormlike conformation in aqueous solution at pH 4 and room temperature. Possessing pH-responsive PDEA and thermo-responsive PMEO2MA grafts arranged in an asymmetric centipede manner within the rod segment, PEO-b-[PGMA-g-(PDEA)(PMEO2MA)] self-assembles into two types spherical aggregates in aqueous solution, depending on solution pH and temperatures. The multiresponsive switching between wormlike unimers and two types of micellar aggregates were characterized by temperature-dependent optical transmittance, dynamic laser light scattering (LLS), AFM, and transmission electron microscopy (TEM).

Fluorescent polymeric assemblies and nanoparticles (NPs) of nanoscale dimensions have become a focus of intensive investigations during the past few decades due to combined advantages such as improved biocompatibility, water dispersibility, stimuli-responsiveness, facile integration into optical detection devices, and the ability of further functionalization. In addition, the chemical composition and morphology of polymeric assemblies and NPs can be modulated via synthetic approaches, leading to the precise spatial organization of multiple fluorophores. Thus, polymeric assemblies and NPs have been utilized to optimize the photoluminescent properties of covalently or physically attached fluorophores and facilely modulate the fluorescence resonance energy transfer (FRET) processes when the polymeric matrix is endowed with stimuli-responsiveness. These fascinating fluorescent polymeric assemblies and NPs offer unique and versatile platforms for the construction of novel detection, imaging, biolabeling, and optoelectronic systems. This feature article focuses on the recent developments of polymeric assemblies and NPs-based stimuli-tunable fluorescent systems and highlights their future practical applications with selected literature reports.

Controlling the packing arrangements of dyes is a facile way of tuning their photophysical and/or photochemical properties, thus enabling new sensing mechanisms for photofunctional tools. Here, we present a general and robust strategy toward water-stable J-aggregated dye-templated nanoassemblies by incorporating an amphiphilic diblock copolymer and a stimuli-responsive dye as the only two building components. An iodo-substituted boron dipyrromethene (BODIPY) was adopted as a template to direct the self-assembly of poly(ethylene glycol)-block-polycaprolactone (PEG−PCL), forming a core−shell nanoplate with slip-stacked BODIPYs as core surrounded by hydrophilic PEG shell. The self-assembled nanoplate is stable in cell culture medium and possesses a built-in stimuli-responsiveness that arises from BODIPY bearing meso-carboxylate protecting group, which is efficiently removed upon treatment with peroxynitrite. The resulting negative charges lead to rearrangement of dyes from J-stacking to nonstacking, which activates photoinduced singlet oxygen production from the nanoassemblies. The stimuli-activatable photosensitivity has been exploited for specific photodynamic ablation of activated RAW 264.7 cells with excessive endogenous peroxynitrite. In light of the generality of the sensing mechanism, the concept described herein will significantly expand the palette of design principles to develop diverse photofunctional tools for biological research and clinical needs.

Well‐defined β‐CD‐terminated poly(N‐isopropylacrylamide) (β‐CD‐PNIPAM) was synthesized via a combination of atom transfer radical polymerization (ATRP) and click chemistry. Moreover, adamantyl‐terminated poly(2‐(diethylamino)ethyl methacrylate) (Ad‐PDEA) was synthesized by ATRP using an adamantane‐containing initiator. Host‐guest inclusion complexation between β‐CD and adamantyl moieties drives the formation of supramolecular double hydrophilic block copolymers (DHBC) from β‐CD‐PNIPAM and Ad‐PDEA. The obtained supramolecular PNIPAM‐b‐PDEA diblock copolymer exhibits intriguing multi‐responsive and reversible micelle‐to‐vesicle transition behavior in aqueous solution by dually playing with solution pH and temperatures.

We report on the fabrication of thermoresponsive poly(N-isopropylacrylamide) nanogel-based dual fluorescent sensors for temperature and Hg 2+ ions, and the effects of thermo-induced nanogel collapse on the detection sensitivity of Hg 2+ ions. Near-monodisperse thermoresponsive nanogels were prepared via emulsion polymerization of N-isopropylacrylamide (NIPAM) and a novel 1,8-naphthalimide-based polarity-sensitive and Hg 2+ -reactive fluorescent monomer (NPTUA, 3). At room temperature, PNIPAM nanogels labeled with a single type of naphthalimide-based dye (NPTUA) can act as ratiometric Hg 2+ probes at the nanomolar level. Upon heating above the phase transition temperature, the fluorescence intensity of NPTUA-labeled nanogels in the absence of Hg 2+ exhibit $3.4-fold increase due to that NPTUA moieties are now located in a more hydrophobic microenvironment. Moreover, it was observed that the detection sensitivity to Hg 2+ can be further improved above the nanogel phase transition temperature. At a nanogel concentration of 0.05 g L À1 and in the same Hg 2+ concentration range (0-3.0 equiv.), $10 fold and $57 fold increase in fluorescence emission intensity ratio changes can be achieved at 25 and 40 C, respectively.