Dopant-Assisted Positive Photoionization Ion Mobility Spectrometry Coupled with Time-Resolved Thermal Desorption for On-Site Detection of Triacetone Triperoxide and Hexamethylene Trioxide Diamine in Complex Matrices.

Peroxide explosives, such as triacetone triperoxide (TATP) and hexamethylene trioxide diamine (HMTD), were often used in the terrorist attacks due to their easy synthesis from readily starting materials. Therefore, an on-site detection method for TATP and HMTD is urgently needed. Herein, we developed a stand-alone dopant-assisted positive photoionization ion mobility spectrometry (DAPP-IMS) coupled with time-resolved thermal desorption introduction for rapid and sensitive detection of TATP and HMTD in complex matrices, such as white solids, soft drinks, and cosmetics.

Assessment of Micro-Basin Tillage as a Soil and Water Conservation Practice in the Black Soil Region of Northeast China.

Micro-basin tillage is a soil and water conservation practice that requires building individual earth blocks along furrows. In this study, plot experiments were conducted to assess the efficiency of micro-basin tillage on sloping croplands between 2012 and 2013 (5°and 7°). The conceptual, optimal, block interval model was used to design micro-basins which are meant to capture the maximum amount of water per unit area.

Increasing sulfate concentrations result in higher sulfide production and phosphorous mobilization in a shallow eutrophic freshwater lake.

Increasing sulfate input has been seen as an issue in management of aquatic ecosystems, but its influences on eutrophic freshwater lakes is not clear. In this study, it was observed that increasing sulfate concentration without additional cyanobacterial bloom biomass (CBB) addition did not have an obvious effect on element cycling during 1-year continuous flow mesocosm experiments in which water and sediments were taken from a shallow eutrophic lake with sulfate levels near 1 mM. However, following addition of CBB to mesocosms, sulfate-reducing bacteria (SRB) were observed in the water column, and increasing numbers of SRB in the water column were associated with higher sulfate input.

Components and Anti-HepG2 Activity Comparison of Lycopodium Alkaloids from Four Geographic Origins.

Lycopodium japonicum Thunb. has attracted great interests due to its rich alkaloids with significant anticancer activity. However, significant chemical differences often exist in a plant species from different geographic origins and affect its quality and bioactivities.

Algal bloom sedimentation induces variable control of lake eutrophication by phosphorus inactivating agents.

Lake eutrophication typically occurs with a syndrome of algae breeding and biomass accumulation (e.g., algal blooms).

The 160 bp Insertion in the Promoter of Rht-B1i Plays a Vital Role in Increasing Wheat Height.

The extensive use of two alleles (Rht-B1b and Rht-D1b) at the Rht-1 locus in wheat allowed dramatic increases in yields, triggering the so-called "Green Revolution." Here, we found that a new natural allelic variation (Rht-B1i) containing a single missense SNP (A614G) in the coding region significantly increased plant height against the genetic background of both Rht-D1a (11.68%) and Rht-D1b (7.

Facile Synthesis of Fe2O3 Nano-Dots@Nitrogen-Doped Graphene for Supercapacitor Electrode with Ultralong Cycle Life in KOH Electrolyte.

Fe2O3 nanodots supported on nitrogen-doped graphene sheets (denoted as Fe2O3 NDs@NG) with different loading masses are prepared through a facile one-pot solvothermal method. The resulting Fe2O3 NDs@NG composites exhibit outstanding electrochemical properties in aqueous KOH electrolyte. Among them, with the optimal loading mass of Fe2O3 NDs, the corresponding Fe2O3 NDs@NG-0.

Concentration, sources, and flux of dissolved organic carbon of precipitation at Lhasa city, the Tibetan Plateau.

Dissolved organic carbon (DOC) plays an important role in the climate system, but few data are available on the Tibetan Plateau (TP). In this study, 89 precipitation samples were collected at Lhasa, the largest city of southern Tibet, from March to December 2013. The average concentration and wet deposition flux of DOC was 1.

Polycyclic aromatic hydrocarbons in soils from the Central-Himalaya region: Distribution, sources, and risks to humans and wildlife.

The Central Himalayas are not only a natural boundary between China and Nepal but also a natural barrier for transport of air masses from South Asia. In this study, 99 samples of surface soil were collected from five regions of Nepal on the southern side of the Central Himalayas, and 65 samples of surface soil were obtained from the northern side on the edge of the Tibetan Plateau, China (TPC). Concentrations of polycyclic aromatic hydrocarbons (PAHs) in soils were measured to determine their distribution, potential for accumulation, and sources, as well as risks to humans and the environment.

Lipoxygenase inhibitors from the latex of Calotropis Procera.

A radical-scavenging, guided phytochemical study of the latex of Calotropis Procera afforded five lignans (1-5), including a new one (4). The structural determination was accomplished using 1D- and 2D-NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and correlation with known compounds. Among the isolated compounds, acylated lignans (3-5) showed stronger antioxidant activity than non-acylated derivatives (1,2).

A Systems Approach to Reverse Engineer Lifespan Extension by Dietary Restriction.

Dietary restriction (DR) is the most powerful natural means to extend lifespan. Although several genes can mediate responses to alternate DR regimens, no single genetic intervention has recapitulated the full effects of DR, and no unified system is known for different DR regimens. Here we obtain temporally resolved transcriptomes during calorie restriction and intermittent fasting in Caenorhabditis elegans and find that early and late responses involve metabolism and cell cycle/DNA damage, respectively.

Evolutionary origin of Rosaceae-specific active non-autonomous hAT elements and their contribution to gene regulation and genomic structural variation.

Transposable elements account for approximately 30 % of the Prunus genome; however, their evolutionary origin and functionality remain largely unclear. In this study, we identified a hAT transposon family, termed Moshan, in Prunus. The Moshan elements consist of three types, aMoshan, tMoshan, and mMoshan.

Complete genome of Marinobacter psychrophilus strain 20041(T) isolated from sea-ice of the Canadian Basin.

Marinobacter psychrophilus strain 20041(T) was isolated from sea-ice of the Canadian Basin. Here we report the complete sequence of the 3.9-Mb genome of this strain.

One-Pot and Facile Fabrication of Hierarchical Branched Pt-Cu Nanoparticles as Excellent Electrocatalysts for Direct Methanol Fuel Cells.

Hierarchical branched nanoparticles are one promising nanostructure with three-dimensional open porous structure composed of integrated branches for superior catalysis. We have successfully synthesized Pt-Cu hierarchical branched nanoparticles (HBNDs) with small size of about 30 nm and composed of integrated ultrathin branches by using a modified polyol process with introduction of poly(vinylpyrrolidone) and HCl. This strategy is expected to be a general strategy to prepare various metallic nanostructures for catalysis.

Constructing a Catalytic Cycle for C-F to C-X (X = O, S, N) Bond Transformation Based on Gold-Mediated Ligand Nucleophilic Attack.

A tricoordinated gold(I) chloride complex, tBuXantphosAuCl, supported by a sterically bulky 9,9-dimethyl-4,5-bis(di-tert-butylphosphino)xanthene ligand (tBuXantphos) was synthesized. This complex features a remarkably longer Au-Cl bond length [2.632(1) Å] than bicoordinated linear gold complexes (2.

Straightforward synthesis of functionalized chroman-4-ones through cascade radical cyclization-coupling of 2-(allyloxy)arylaldehydes.

A novel and direct approach to synthesize a series of phosphonate, azide and hydroxy functionalized chroman-4-ones has been developed. The cascade transformation appears to proceed through an intramolecular addition of an in situ generated acyl radical onto the alkene, followed by a selective nucleophilic radical-electrophilic radical cross coupling.

Transcription Factor RFX2 Is a Key Regulator of Mouse Spermiogenesis.

The regulatory factor X (RFX) family of transcription factors is crucial for ciliogenesis throughout evolution. In mice, Rfx1-4 are highly expressed in the testis where flagellated sperm are produced, but the functions of these factors in spermatogenesis remain unknown. Here, we report the production and characterization of the Rfx2 knockout mice.

Accessing the Triplet State in Heavy-Atom-Free Perylene Diimides.

Previous studies of perylenediimides (PDIs) mostly utilized the lowest singlet excited state S1 . Generation of a triplet excited state (T1 ) in PDIs is important for applications ranging from photodynamic therapy to photovoltaics; however, it remains a formidable task. Herein, we developed a heavy-atom-free strategy to prompt the T1 ←S1 intersystem crossing (ISC) by introducing electron-donating aryl (Ar) groups at the head positions of an electron-deficient perylenediimide (PDI) core.

Label-free immunosensor based on one-step electrodeposition of chitosan-gold nanoparticles biocompatible film on Au microelectrode for determination of aflatoxin B1 in maize.

Gold nanoparticles (AuNPs) embedded in chitosan (CHI) film, well-dispersed and smaller in size (about 10 nm), were fabricated by one-step electrodeposion on Au microelectrode in solution containing chitosan and chloride trihydrate. The nano-structure CHI-AuNPs composite film offers abundant amine groups, good conductivity, excellent biocompatibility and stability for antibody immobilization. The combination of aflatoxin B1 (AFB1) with immobilized antibody introduces a barrier to electron transfer, resulting in current decreasement.

Copy number variation of a gene cluster encoding endopolygalacturonase mediates flesh texture and stone adhesion in peach.

Texture is an important attribute affecting consumer perception of fruit quality. Peach melting flesh and flesh adhesion to stone (endocarp) are simply inherited and controlled by the F-M locus on linkage group (LG) 4. Here, we report that two genes encoding endopolygalacturonase (endoPG) in the F-M locus, designated PpendoPGF and PpendoPGM, are associated with the melting flesh and stone adhesion traits.

High Conductive Two-Dimensional Covalent Organic Framework for Lithium Storage with Large Capacity.

A high conductive 2D COF polyporphyrin (TThPP) linked by 4-thiophenephenyl groups was synthesized through an in situ chemical oxidative polymerization on the surface of copper foil. The TThPP films were used as the anode of lithium-ion battery, which exhibited high specific capacities, excellent rate performances, and long cycle lives due to the alignment of 2D polyporphyrin nanosheets, and they (i) can highly efficiently adsorb Li atoms, (ii) have short-ended paths for the fast lithium ion diffusion, and (iii) open nanopores holding electrolyte. The reversible capacity is up to 666 mAh/g.

Periodic peristalsis releasing constrained water in high solids enzymatic hydrolysis of steam exploded corn stover.

Periodic peristalsis was used to release water constraint and increase high solids enzymatic hydrolysis efficiency. Glucan and xylan conversion in periodic peristalsis enzymatic hydrolysis (PPEH) at 21% solid loading increased by 5.2-6.

Single-Molecule Nanocatalysis Shows In Situ Deactivation of Pt/C Electrocatalysts during the Hydrogen-Oxidation Reaction.

By coupling a Pt-catalyzed fluorogenic reaction with the Pt-electrocatalyzed hydrogen-oxidation reaction (HOR), we combine single-molecule fluorescence microscopy with traditional electrochemical methods to study the real-time deactivation kinetics of a Pt/C electrocatalyst at single-particle level during electrocatalytic hydrogen-oxidation reaction. The decay of the catalytic performance of Pt/C could be mainly attributed to the electrocatalysis-induced etching or dissolution of Pt nanoparticles. Spontaneous regeneration of activity and incubation period of the Pt electrocatalyst were also observed at single-particle level.

Analysis of Isoquinoline Alkaloid Composition and Wound-Induced Variation in Nelumbo Using HPLC-MS/MS.

Alkaloids are the most relevant bioactive components in lotus, a traditional herb in Asia, but little is known about their qualitative and quantitative distributions. Here, we report on the alkaloid composition in various lotus organs. Lotus laminae and embryos are rich in isoquinoline alkaloids, whereas petioles and rhizomes contain trace amounts of alkaloids.

Negative regulation of phosphatidylinositol 3-phosphate levels in early-to-late endosome conversion.

Phosphatidylinositol 3-phosphate (PtdIns3P) plays a central role in endosome fusion, recycling, sorting, and early-to-late endosome conversion, but the mechanisms that determine how the correct endosomal PtdIns3P level is achieved remain largely elusive. Here we identify two new factors, SORF-1 and SORF-2, as essential PtdIns3P regulators in Caenorhabditis elegans. Loss of sorf-1 or sorf-2 leads to greatly elevated endosomal PtdIns3P, which drives excessive fusion of early endosomes.