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A large change in albedo has a significant effect on glacier ablation. Atmospheric aerosols – e.g. black carbon (BC) and dust – can reduce the albedo of glaciers and thus contribute to their melting. In this study, two main themes were explored: (1) the decrease in albedo of the Zhadang glacier on Mt. Nyainqentanglha between 2001 and 2012, as observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) on-board the Terra satellite, and the correlation of this albedo with mass balance; and (2) the concentrations of BC and dust in the glacier measured during 2012, and the associated impacts of these impurities on albedo and radiative forcings (RF). The average albedo of the Zhadang glacier from the MODIS increased with the altitude and fluctuated but had a decreasing trend (−0.003 a−1) during the period 2001–2012, with the highest (0.722) in 2003 and the lowest (0.597) in 2009 and 2010. The mass balance of the glacier has a positively significant correlation with its surface albedo derived from MODIS. Snow samples were collected on the Zhadang glacier to measure the BC and dust in the summer of 2012. The impacts of BC and dust on albedo reduction in different melting conditions were identified with the SNow ICe Aerosol Radiative (SNICAR) model initiated by in situ observation data. The sensitivity analysis showed that BC was a major factor in albedo reduction when the glacier was covered by newly fallen snow. Nevertheless, the contribution of dust to albedo reduction can reach as high as 56%, much exceeding that of BC (28%), when the glacier experiences strong surficial melting and its surface is almost bare ice. The average RF caused by dust could increase from 1.1 to 8.6 W m−2, exceeding the RF caused by BC after snow was deposited and surface melting occurred in the Zhadang glacier. This implies that it may be dust that primarily dominates the melting of some glaciers in the inner Tibetan Plateau during melting seasons, rather than BC.

Using the techniques of neural networks (NN), we study the three-dimensional (3D) five-state ferromagnetic Potts model on the cubic lattice as well as the two-dimensional (2D) three-state antiferromagnetic Potts model on the square lattice. Unlike the conventional approach, here we follow the idea employed by Li et al (2018 Ann. Phys., NY 391 312-331). Specifically, instead of numerically generating numerous objects for the training, the whole or part of the theoretical ground state configurations of the studied models are considered as the training sets. Remarkably, our investigation of these two models provides convincing evidence for the effectiveness of the method of preparing training sets used in this study. In particular, the results of the 3D model obtained here imply that the NN approach is as efficient as the traditional method since the signal of a first order phase transition, namely tunneling between two channels, determined by the NN method is as strong as that calculated with the Monte Carlo technique. Furthermore, the outcomes associated with the considered 2D system indicate even little partial information of the ground states can lead to conclusive results regarding the studied phase transition. The achievements reached in our investigation demonstrate that the performance of NN, using certain amount of the theoretical ground state configurations as the training sets, is impressive.

The introduction of the Simian virus 40 (SV40) early region, the telomerase catalytic subunit ( hTERT ) and an oncogenic allele of H-Ras directly transforms primary human cells. SV40 small T antigen (ST), which forms a complex with protein phosphatase 2A (PP2A) and inhibits PP2A activity, is believed to have a critical role in the malignant transformation of human cells. Recent evidence has shown that aberrant microRNA (miRNA) expression patterns are correlated with cancer development. Here, we identified miR-27a as a differentially expressed miRNA in SV40 ST-expressing cells. miR-27a is upregulated in SV40 ST-transformed human bronchial epithelial cells (HBERST). Suppression of miR-27a expression in HBERST cells or lung cancer cell lines (NCI-H226 and SK-MES-1) that exhibited high levels of miR-27a expression lead to cell growth arrested in the G 0 –G 1 phase. In addition, suppression of miR-27a in HBERST cells attenuated the capacity of such cells to grow in an anchorage-independent manner. We also found that suppression of the PP2A B56γ expression resulted in upregulation of miR-27a similar to that achieved by the introduction of ST, indicating that dysregulation of miR-27a expression in ST-expressing cells was mediated by the ST–PP2A interaction. Moreover, we discovered that Fbxw7 gene encoding F-box/WD repeat-containing protein 7 was a potential miR-27a target validated by dual-luciferase reporter system analysis. The inverse correlation between miR-27a expression levels and Fbxw7 protein expression was further confirmed in both cell models and human tumor samples. Fbxw7 regulates cell-cycle progression through the ubiquitin-dependent proteolysis of a set of substrates, including c-Myc, c-Jun, cyclin E1 and Notch 1. Thus, promotion of cell growth arising from the suppression of Fbxw7 by miR-27a overexpression might be responsible for the viral oncoprotein ST-induced malignant transformation. These observations demonstrate that miR-27a functions as an oncogene in human tumorigenesis.

Spectral similarity indices were used to select similar soil samples from a spectral library and improve the predictive accuracy of target samples. There are many similarity indices available, and precisely how to select the optimum index has become a critical question. Five similarity indices were evaluated: Spectral angle mapper (SAM), Euclidean distance (ED), Mahalanobis distance (MD), SAM_pca and ED_pca in the space of principal components applied to a global soil spectral library. The accordance between spectral and compositional similarity was used to select the optimum index. Then the optimum index was evaluated if it can maintain the greatest predictive accuracy when selecting similar samples from a spectral library for the prediction of a target sample using a partial least squares regression (PLSR) model. The evaluated physiochemical properties were: soil organic carbon, pH, cation exchange capacity (CEC), clay, silt, and sand content. SAM and SAM_pca selected samples were closer in composition compared to the target samples. Based on similar samples selected using these two indices, PLSR models achieved the highest predictive accuracy for all soil properties, save for CEC. This validates the hypothesis that the accordance information between spectral and compositional similarity can help select the appropriate similarity index when selecting similar samples from a spectral library for prediction.

A regulator of the protein phosphatase 2A (PP2A), α4, has been implicated in a variety of functions that regulate many cellular processes. To explore the role of α4 in human cell transformation and tumorigenesis, we show that α4 is highly expressed in human cells transformed by chemical carcinogens including benzo( a )pyrene, aflatoxin B 1 , N -methyl- N ′-nitro- N -nitrosoguanidine, nickel sulfate and in several hepatic and lung cancer cell lines. In addition, overexpression of α4 was detected in 87.5% (74/80) of primary hepatocellular carcinomas, 84.0% (21/25) of primary lung cancers and 81.8% (9/11) of primary breast cancers, indicating that α4 is ubiquitously highly expressed in human cancer. Functional studies revealed that elevated α4 expression results in an increase in cell proliferation, promotion of cell survival and decreased PP2A-attributable activity. Importantly, ectopic expression of α4 permits non-transformed human embryonic kidney cells (HEKTER) and L02R cells to form tumors in immunodeficient mice. Furthermore, we show that the highly expressed α4 in transformed cells or human tumors is not regulated by DNA hypomethylation. A microRNA, miR-34b, that suppresses the expression of α4 through specific binding to the 3′-untranslated region of α4 is downregulated in transformed or human lung tumors. Taken together, these observations identify that α4 possesses an oncogenic function. Reduction of PP2A activity due to an enhanced α4–PP2A interaction contributes directly to chemical carcinogen-induced tumorigenesis.

Increasing consumer awareness and soaring prices for raw material make reverse logistics an ever more important aspect of the product life cycle. However, most research focuses on the remanufacturing and recycling process leaving the actual tasks of waste collection behind. Moreover, existing research on waste collection typically assumes the problem to be deterministic, neglecting its stochastic nature. This study first diagnoses the solid waste collection problem; it is classified as an inventory control problem with confluent material flows and stochastic demand. A type of control system designed for this kind of problem is the kanban system. In response, the applicability of a kanban system for solid waste collection is discussed. While kanbans are a suitable mean to signal time and quantity of waste collection, the large quantity of collection points and geographical distances involved hinder its direct application. How the kanban system can be driven by the Internet of Things (IoT) was consequently the second objective of this study. Using a framework of an IoT driven production logistics system the control structure of the original kanban system has been analyzed. Out of this analysis the architecture of an IoT driven kanban system for solid waste collection is proposed.

We have previously demonstrated that the serine/threonine protein phosphatase-1 (PP-1) plays an important role in promoting cell survival. However, the molecular mechanisms by which PP-1 promotes survival remain largely unknown. In the present study, we provide evidence to show that PP-1 can directly dephosphorylate a master regulator of apoptosis, p53, to negatively modulate its transcriptional and apoptotic activities, and thus to promote cell survival. As a transcriptional factor, the function of p53 can be greatly regulated by phosphorylation and dephosphorylation. While the kinases responsible for phosphorylation of the 17 serine/threonine sites have been identified, the dephosphorylation of these sites remains largely unknown. In the present study, we demonstrate that PP-1 can dephosphorylate p53 at Ser-15 and Ser-37 through co-immunoprecipitation, in vitro and in vivo dephosphorylation assays, overexpression and silence of the gene encoding the catalytic subunit for PP-1. We further show that mutations mimicking constitutive dephosphorylation or phosphorylation of p53 at these sites attenuate or enhance its transcriptional activity, respectively. As a result of the changed p53 activity, expression of the downstream apoptosis-related genes such as bcl-2 and bax is accordingly altered and the apoptotic events are either largely abrogated or enhanced. Thus, our results demonstrate that PP-1 directly dephosphorylates p53, and dephosphorylation of p53 has as important impact on its functions as phosphorylation does. In addition, our results reveal that one of the molecular mechanisms by which PP-1 promotes cell survival is to dephosphorylate p53, and thus negatively regulate p53-dependent death pathway.

Pyrolysis experiments of melamine were carried out under high pressure of 5 GPa and different temperatures. The crystal structure, chemical bonding, and composition of the melamine pyrolysate were studied by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray energy-dispersive analysis (EDX), and combustion elemental analysis. A new C–N–H phase was found in the pyrolysate at 5 GPa and 800 °C. The structure is tentatively indexed as a monoclinic symmetry, with the following lattice parameters: a = 8.5368 (±0.0009)Å, b = 9.1153 (±0.0010)Å, c = 10.2440 (±0.0011)Å, α = γ = 90°, and β = 95.5696 (±0.0016)°. The photoluminescence behavior of the pyrolysates was investigated. A blue emission at 421 nm for the C–N–H phase was observed under the ultraviolet light excitation of 365 nm.

Microsatellites have many desirable marker properties. There has been no report of the development and utilization of microsatellite markers in oat. The objectives of the present study were to construct oat microsatellite-enriched libraries, to isolate microsatellite sequences and evaluate their level of polymorphism in Avena species and oat cultivars. One hundred clones were isolated and sequenced from three oat microsatellite-libraries enriched for either (AC/TG)^sub n^, (AG/TC)^sub n^ or (AAG/TTC)^sub n^ repeats. Seventy eight clones contained microsatellites. A database search showed that 42% of the microsatellite flanking sequences shared significant homology with various repetitive elements. Alu and retrotransposon sequences were the two largest groups associated with the microsatellites. Forty four primer sets were used to amplify the DNA from 12 Avena species and 20 Avena sativa cultivars. Sixty two percent of the primers revealed polymorphism among the Avena species, but only 36% among the cultivars. In the cultivars, the microsatellites associated with repetitive elements were less polymorphic than those not associated with repetitive elements. Only 25% of the microsatellites associated with repetitive elements were polymorphic, while 46% of the microsatellites not associated with repetitive elements showed polymorphism in the cultivars. An average of four alleles with a polymorphism information content (PIC) of 0.57 per primer set was detected among the Avena species, and 3.8 alleles with a PIC of 0.55 among the cultivars. In addition, 54 barley microsatellite primers were tested in Avena species and 26% of the primers amplified microsatellites from oat. Using microsatellite polymorphisms, dendrograms were constructed showing phylogenetic relationships among Avena species and genetic relationships among oat cultivars.[PUBLICATION ABSTRACT]