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Plant height is a key agronomic trait that affects yield and is controlled by both phytohormone gibberellin (GA) and ultraviolet-B (UV-B) irradiation. However, whether and how plant height is modulated by UV-B-mediated changes in GA metabolism are not well understood. It has not been reported that the E3 ubiquitin ligase Anaphase Promoting Complex/Cyclosome (APC/C) is involved in the regulation of plant growth in response to environmental factors. We perform a forward genetic screen in soybean and find that a mutation in Glycine max Increased Leaf Petiole Angle1 (GmILPA1), encoding a subunit of the APC/C, lead to dwarfism under UV-B irradiation. UV-B promotes the accumulation of GmILPA1, which ubiquitinate the GA catabolic enzyme GA2 OXIDASE-like (GmGA2ox-like), resulting in its degradation in a UV-B-dependent manner. Another E3 ligase, GmUBL1, also ubiquitinate GmGA2ox-like and enhance the GmILPA1-mediated degradation of GmGA2ox-like, which suggest that GmILPA1-GmGA2ox-like module counteract the UV-B-mediated reduction of bioactive GAs. We also determine that GmILPA1 is a target of selection during soybean domestication and breeding. The deletion (Indel-665) in the promoter might facilitate the adaptation of soybean to high UV-B irradiation. This study indicates that an evolutionary GmILPA1 variant has the capability to develop ideal plant architecture with soybean cultivars. Gibberellins (GA) negatively regulate UVB-mediated suppression of plant height in plants. Here, the authors show that GmILPA1-mediated degradation of GmGA2ox-like protein counteract the UV-B-mediated reduction of bioactive GAs contributing to the linkage between the affection of UV-B and GA on plant height of soybean. [ABSTRACT FROM AUTHOR]

This study was designed to assess the distribution of organochlorines (OCs) in fish species, their spatio-temporal variations, bioaccumulation potential, and associated human health risks via dietary intake. The levels of twenty-three organochlorine pesticides (OCPs) and thirty-five polychlorinated biphenyls (PCBs) were analyzed in six fish species collected from the riverine ecosystem of Punjab Province, Pakistan. The results indicated that the mean levels of Σ23OCPs were 74.1 ng/g ww and 184 ng/g ww, and for Σ35PCBs the levels were 38.8 ng/g ww and 74.8 ng/g ww in herbivorous and carnivorous fish species, respectively. The most abundant contaminants in all fish species were DDTs (65%) and HCHs (14%) among OCPs and heavier PCB congeners (62%) among PCBs. As for dioxin-like PCBs, the WHO toxic equivalency values (ng TEQ/g ww) were in the range of 0.21 (Cyprinus Carpio) to 2.38 (Rita Rita), exceeding the maximum allowable limit of 0.004 ng TEQ/g, ww by the European Commission. Spatio-temporal analysis indicated relatively higher OC levels in winter season with elevated concentrations in fish samples from industrial zone. The bioconcentration factor (L/kg) values ranged from 723 to 2773 for PCBs and 315 to 923 for OCPs in all fish species, with higher levels were reported in carnivorous species. The human health risk assessment at both 50th and 95th percentiles revealed the absence of any significant non-carcinogenic risk as calculated HR was less than 1. However, the critical carcinogenic risk was found to be associated for most of the contaminants, signifying the dietary exposure to OCPs and PCBs might pose the public health concern. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine the occurrence, spatio-temporal variations, source apportioning, and ecological risk assessment of selected PCBs and OCPs in surface water and sediments collected riverine environment of Punjab province, Pakistan. The concentration of ΣOCPs (water: 64–455 ng/L; sediments: 117–616 ng/g) and ΣPCBs (water: 2–132 ng/L; sediments: 3.27–200 ng/g) was found comparatively higher than the levels reported from other parts of the world. The higher concentrations of DDTs and HCHs were detected in both studied matrices, whereas among PCBs, CB-28, 49 and CB-37, 82 were dominant in water and sediments, respectively. The isomeric ratios including α-HCH/γ-HCH, (DDE + DDD) / DDTs, and α /β-endosulfan reflected the recent use of lindane, technical DDT, and endosulfan in the study area. The WHO–TEQ values of DL-PCBs ranged from 3.6 × 10−6 to 0.115 ng/L and 8.7 × 10−6 to 0.157 ng/g in surface water and sediments in both seasons, respectively. The spatial variation analysis revealed that the sites in the industrial and agricultural zones were highly contaminated. The OCPs and PCBs fluxes to downstream areas were estimated to be 12.4 tons/year and 1.9 tons/year, respectively. The significant ecological risks were estimated to be posed by OCPs and PCBs, as their levels in 67% and 62% of surface water and sediment samples were exceeding the threshold limits, highlighting effects to ecological integrities. [ABSTRACT FROM AUTHOR]

Incomplete understanding of the sources of secondary organic aerosol (SOA) leads to large uncertainty in both air quality management and in climate change assessment. Chemical reactions occurring in the atmospheric aqueous phase represent an important source of SOA mass, yet, the effects of anthropogenic emissions on the aqueous SOA (aqSOA) are not well constrained. Here we use compound-specific dual-carbon isotopic fingerprints (δ13C and Δ14C) of dominant aqSOA molecules, such as oxalic acid, to track the precursor sources and formation mechanisms of aqSOA. Substantial stable carbon isotope fractionation of aqSOA molecules provides robust evidence for extensive aqueous-phase processing. Contrary to the paradigm that these aqSOA compounds are largely biogenic, radiocarbon-based source apportionments show that fossil precursors produced over one-half of the aqSOA molecules. Large fractions of fossil-derived aqSOA contribute substantially to the total water-soluble organic aerosol load and hence impact projections of both air quality and anthropogenic radiative forcing. Our findings reveal the importance of fossil emissions for aqSOA with effects on climate and air quality. Isotope fingerprinting is used to track precursor sources and formation pathways of aqueous SOA, such as oxalic acid, finding that fossil fuel precursors contributions have largely been underestimated. [ABSTRACT FROM AUTHOR]

Municipal solid waste incineration products of bottom ash (BA), fly ash (FA), and pickling sludge (PS), causing severe environmental pollution, were transformed into glass ceramic foams with the aid of CaCO3 as a pore-foaming agent during sintering. The effect of the BA/FA mass ratio on the phase composition, pore morphology, pore size distribution, physical properties, and glass structure was investigated, with results showing that with the increase in the BA/FA ratio, the content of the glass phase, Si-O-Si, and Q3Si units decrease gradually. The glass transmission temperature of the mixture was also reduced. When combined, the glass viscosity decreases, causing bubble coalescence and uneven pore distribution. Glass ceramic foams with uniform spherical pores are fabricated. When the content of BA, FA, and PS are 35wt%, 45wt%, and 20wt%, respectively, contributing to high performance glass ceramic foams with a bulk density of 1.76 g/cm3, porosity of 56.01%, and compressive strength exceeding 16.23 MPa. This versatile and low-cost approach provides new insight into synergistically recycling solid wastes. [ABSTRACT FROM AUTHOR]

The mobility of arsenic (As) in soil depends on its sorption/desorption processes on soil particles. Plant uptake locally lowers As concentration in soil pore water, which would trigger resupplies of As from soil solid phase. To better understand the fate of As in soil system after its inputs into soil and its subsequent dynamic processes, diffusive gradients in thin films (DGT) technique along with DGT-induced fluxes in soils (DIFS) model were introduced to study the kinetic information of As in soils, including its response time (TC) and resupply rate constant (k−1). To achieve a series of soils with gradient As level, two different types of soils with similar As level (total As in soil JL is 7.4 mg kg−1, while in soil BJ is 6.5 mg kg−1) were collected and amended with exogenous As. Then, DGT deployments were carried out following a period of 90-day soil incubation. The simulated TC values in non-amended soil JL and soil BJ were 0.036 and 0.001 s−1, respectively. The difference may due to the properties of these two soils, including pH values and contents of adsorption materials, such as Fe and Al compounds. After As inputs into soils, the intrinsic rate of As release from the solid phase to the solution phase in As-amended JL soil was much higher than that in non-amended soil. While for soil BJ, a decreasing trend was observed after As spiking. The redistribution of As may responsible for the different variation trends of As kinetics in these two soils after As spiking. The results indicated that the distribution coefficient of As (Kd) in soil was mainly affected by soil Olsen-P content due to an ubiquitous competition between P and As on soil particles. [ABSTRACT FROM AUTHOR]

In this paper, novel three-dimensional (3D) CuO precursor was synthesized under the ice water bath. The flower-like micellar polyp-phenylenediamine (PpPD) was synthesized when the p-phenylenediamine-salicylic acid ([SA]/PPD) ratio was 1:1. The two amino groups of PpPD interacted with Cu by the coordination interactions. After calcination in the air, dandelion-like CuO nanoflowers were successfully prepared. The physicochemical properties of the as-prepared CuO were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), infrared spectrometer (FT-IR), UV-vis absorption spectra (UV-vis), and energy-dispersive spectrometer (EDS). In the participation of HO, the as-obtained CuO nanoflowers exhibited high efficiency on the decolorization of rhodamine B (RhB) by the synergy of ·OH and ·O . The novel dandelion-like CuO also provided more active sites to improve the photocatalytic effect. It can be applied to the degradation of dyes, such as RhB, and plays a role in environmental pollution control. [ABSTRACT FROM AUTHOR]

In this work, o-phenylenediamine-m-phenylenediamine copolymer dots (omCPs) with designed surface groups are synthesized and characterized. Here, we explored a simple, rapid semiquantitative detection system for Cu2+ with a wide detection range (5–7 orders of magnitude) based on the fluorescence in the solid state of omCPs and their tunable detection limits. The construction and application of the rapid semiquantitative detection system for Cu2+ are developed and demonstrated for the practical applications. What’s more, the detection limit can be modulated easily by adjusting the surface groups of these dots through the monomer dose control before the co-polymerization. Moreover, we demonstrated that this new technological approach is suitable for the semiquantitative determination of other ions pollutants (i.e., Na+, K+, Cu2+, Pb2+, Hg2+, and NO2−) in environmental water. [ABSTRACT FROM AUTHOR]

Mobile devices have steadily gained acceptance as a multimedia platform, not only that, one of the most valuable pieces of contextual information for an intelligent mobile application is the user's location. The university campus is an interesting application environment for location-based and context-aware mobile services: wherever the students are, they are eager to announce to others and want to know what happens in the university campus, even alumni always care about the latest in his or her campus. The Campus View, what is described in this article, is a smart-phone based context and location-aware video sharing mobile application implemented on Android 2.1. It first gives a full panorama to one Chinese university campus, which will provide a campus overview and variations to alumni and potential students. Different from Street-view of Google which was only created once and demands not to drive anywhere more than once, our campus panorama is timely updated by our DIYed Street-view camera. What's more, the application users inside the campus can use it to recode the latest happenstance and then upload the video short with Geo-information to the server. The recoded video short will be further shared as a H. 264 stream attached to a specific panorama. This paper presents the development framework of Campus View application and an evaluation of key framework components to assess their consumption of mobile device's resources. [ABSTRACT FROM AUTHOR]

By taking into account the valence electron number and periodic number of constituting metals, a new method is first proposed to calculate the structural enthalpy in the Miedema's model and the modified Miedema's model is then used to predict the formation of metastable phases in Ni-Ti system. To testify the relevance of the present prediction, the multilayered films of NiTi ( x=27.3, 30.5, 42.4, 83.1, 89) are prepared and irradiated by 200 keV xenon ions. Experiment results reveal that uniform amorphous phases are obtained in the NiTi, NiTi, and NiTi films by increasing the irradiation dose. While for the NiTi and NiTi films, an hcp Ti-based solid solution phase and a bcc Ti-rich solid solution phase coexist upon irradiation dose higher than 6×10 Xe/cm. The predictions of relative stabilities of metastable phases in Ni-Ti system by the modified Miedema's model match well with IBM experiments, thus justifying the modification proposed in the present study. [ABSTRACT FROM AUTHOR]