Municipal solid waste is a significant contributor to greenhouse gas emissions through decomposition and life-cycle activities processes. The majority of these emissions are a result of landfilling, ...which remains the primary waste disposal strategy internationally. As a result, countries have been incorporating alternative forms of waste management strategies such as energy recovery from landfill gas capture, aerobic landfilling (aerox landfills), pre-composting of waste prior to landfilling, landfill capping and composting of the organic fraction of municipal solid waste. As the changing global climate has been one of the major environmental challenges facing the world today, there is an increasing need to understand the impact of waste management on greenhouse gas emissions. This review paper serves to provide an overview on the impact of landfilling (and its various alternatives) and composting on greenhouse gas emissions taking into account streamlined life cycle activities and the decomposition process. The review suggests greenhouse gas emissions from waste decomposition are considerably higher for landfills than composting. However, mixed results were found for greenhouse gas emissions for landfill and composting operational activities. Nonetheless, in general, net greenhouse gas emissions for landfills tend to be higher than that for composting facilities.
Although significant advances have recently been made in the diagnosis and treatment of cervical carcinoma, the long-term survival rate for advanced cervical cancer remains low. Therefore, an urgent ...need exists to both uncover the molecular mechanisms and identify potential therapeutic targets for the treatment of cervical cancer. MicroRNAs (miRNAs) have important roles in cancer progression and could be used as either potential therapeutic agents or targets. miR-506 is a component of an X chromosome-linked miRNA cluster. The biological functions of miR-506 have not been well established. In this study, we found that miR-506 expression was downregulated in approximately 80% of the cervical cancer samples examined and inversely correlated with the expression of Ki-67, a marker of cell proliferation. Gain-of-function and loss-of-function studies in human cervical cancer, Caski and SiHa cells, demonstrated that miR-506 acts as a tumor suppressor by inhibiting cervical cancer growth in vitro and in vivo. Further studies showed that miR-506 induced cell cycle arrest at the G1/S transition, and enhanced apoptosis and chemosensitivity of cervical cancer cell. We subsequently identified Gli3, a hedgehog pathway transcription factor, as a direct target of miR-506 in cervical cancer. Furthermore, Gli3 silencing recapitulated the effects of miR-506, and reintroduction of Gli3 abrogated miR-506-induced cell growth arrest and apoptosis. Taken together, we conclude that miR-506 exerts its anti-proliferative function by directly targeting Gli3. This newly identified miR-506/Gli3 axis provides further insight into the pathogenesis of cervical cancer and indicates a potential novel therapeutic agent for the treatment of cervical cancer.
Hardening evolution of AZ31B Mg sheet Lou, X.Y.; Li, M.; Boger, R.K. ...
International journal of plasticity,
2007, 2007-01-00, 20070101, Letnik:
23, Številka:
1
Journal Article
Recenzirano
The monotonic and cyclic mechanical behavior of O-temper AZ31B Mg sheet was measured in large-strain tension/compression and simple shear. Metallography, acoustic emission (AE), and texture ...measurements revealed twinning during in-plane compression and untwinning upon subsequent tension, producing asymmetric yield and hardening evolution. A working model of deformation mechanisms consistent with the results and with the literature was constructed on the basis of predominantly basal slip for initial tension, twinning for initial compression, and untwinning for tension following compression. The activation stress for twinning is larger than that for untwinning, presumably because of the need for nucleation. Increased accumulated hardening increases the twin nucleation stress, but has little effect on the untwinning stress. Multiple-cycle deformation tends to saturate, with larger strain cycles saturating more slowly. A novel analysis based on saturated cycling was used to estimate the relative magnitude of hardening effects related to twinning. For a 4% strain range, the obstacle strength of twins to slip is 3
MPa, approximately 1/3 the magnitude of textural hardening caused by twin formation (10
MPa). The difference in activation stress of twinning versus untwinning (11
MPa) is of the same magnitude as textural hardening.
Abstract
At the interface between monolayer FeSe films and SrTiO
3
substrates the superconducting transition temperature (
T
c
) is unexpectedly high, triggering a surge of excitement. The mechanism ...for the
T
c
enhancement has been the central question, as it may present a new strategy for seeking out higher
T
c
materials. To reveal this enigmatic mechanism, by combining advances in high quality interface growth,
16
O
$$\leftrightarrow$$
↔
18
O isotope substitution, and extensive data from angle resolved photoemission spectroscopy, we provide striking evidence that the high
T
c
in FeSe/SrTiO
3
is the cooperative effect of the intrinsic pairing mechanism in the FeSe and interactions between the FeSe electrons and SrTiO
3
phonons. Furthermore, our results point to the promising prospect that similar cooperation between different Cooper pairing channels may be a general framework to understand and design high-temperature superconductors.
FeSe layer-based superconductors exhibit exotic and distinctive properties. The undoped FeSe shows nematicity and superconductivity, while the heavily electron-doped KxFe2-ySe2 and single-layer ...FeSe/SrTiO3 possess high superconducting transition temperatures that pose theoretical challenges. However, a comprehensive study on the doping dependence of an FeSe layer-based superconductor is still lacking due to the lack of a clean means of doping control. Through angle-resolved photoemission spectroscopy studies on K-dosed thick FeSe films and FeSe0.93S0.07 bulk crystals, here we reveal the internal connections between these two types of FeSe-based superconductors, and obtain superconductivity below ∼ 46 K in an FeSe layer under electron doping without interfacial effects. Moreover, we discover an exotic phase diagram of FeSe with electron doping, including a nematic phase, a superconducting dome, a correlation-driven insulating phase and a metallic phase. Such an anomalous phase diagram unveils the remarkable complexity, and highlights the importance of correlations in FeSe layer-based superconductors.
At the interface between monolayer FeSe films and SrTiO
substrates the superconducting transition temperature (T
) is unexpectedly high, triggering a surge of excitement. The mechanism for the T
...enhancement has been the central question, as it may present a new strategy for seeking out higher T
materials. To reveal this enigmatic mechanism, by combining advances in high quality interface growth,
O Formula: see text
O isotope substitution, and extensive data from angle resolved photoemission spectroscopy, we provide striking evidence that the high T
in FeSe/SrTiO
is the cooperative effect of the intrinsic pairing mechanism in the FeSe and interactions between the FeSe electrons and SrTiO
phonons. Furthermore, our results point to the promising prospect that similar cooperation between different Cooper pairing channels may be a general framework to understand and design high-temperature superconductors.
A facile one‐step template‐free method based on a novel inside‐out Ostwald ripening mechanism is developed for inexpensive mass preparation of hollow and hollow core/shell‐type SnO2 nanostructures ...using potassium stannate as the precursor. As‐prepared SnO2 hollow nanospheres (see figure) exhibit ultrahigh lithium storage capacity and improved cycle performance as high‐energy anode materials in lithium‐ion secondary batteries.
A one‐step, self‐supported topotactic transformation approach for synthesizing electrochemically active Co3O4 needlelike nanotubes is reported. Used as the active material in the negative electrode ...of a rechargeable lithium ion battery, the Co3O4 nanotubes manifest ultrahigh Li storage capacity with improved cycle life and rate capability. These features are discussed in terms of the unique structure of the materials.
The kaon identification is crucial for the flavor physics, and also benefits the flavor and charge reconstruction of the jets. We explore the particle identification capability for tracks with ...momenta ranging from 2–20 GeV/c using the
dE
/
dx
measurements in the Time Projection Chamber at the future Circular Electron-Positron Collider. Based on Monte Carlo simulation, we anticipate that an average
3.2
σ
(
2.6
σ
)
K
/
π
separation can be achieved based on
dE
/
dx
information for an optimistic (conservative) extrapolation of the simulated performance to the final system. Time-of-flight (TOF) information from the Electromagnetic Calorimeter can provide
K
/
π
separation around 1 GeV/c and reduce the
K
/
p
mis-identification rate. By combining the
dE
/
dx
and TOF information, we estimate that in the optimistic scenario a kaon selection in inclusive hadronic
Z
decays with both the average efficiency and purity approaching 95% can be achieved.
PDF
