Biochar was prepared using a low temperature pyrolysis method from nine plant materials including non-leguminous straw from canola, wheat, corn, rice and rice hull and leguminous straw from soybean, ...peanut, faba bean and mung bean. Soil pH increased during incubation of the soil with all nine biochar samples added at 10 g/kg. The biochar from legume materials resulted in greater increases in soil pH than from non-legume materials. The addition of biochar also increased exchangeable base cations, effective cation exchange capacity, and base saturation, whereas soil exchangeable Al and exchangeable acidity decreased as expected. The liming effects of the biochar samples on soil acidity correlated with alkalinity with a close linear correlation between soil pH and biochar alkalinity (R² = 0.95). Therefore, biochar alkalinity is a key factor in controlling the liming effect on acid soils. The incorporation of biochar from crop residues, especially from leguminous plants, can both correct soil acidity and improve soil fertility.
The most recent version of the European Society for Medical Oncology (ESMO) consensus guidelines for the treatment of patients with metastatic colorectal cancer (mCRC) was published in 2016, ...identifying both a more strategic approach to the administration of the available systemic therapy choices, and a greater emphasis on the use of ablative techniques, including surgery. At the 2016 ESMO Asia Meeting, in December 2016, it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting, endorsed by both ESMO and JSMO, immediately after the JSMO 2017 Annual Meeting. The aim was to adapt the ESMO consensus guidelines to take into account the ethnic differences relating to the toxicity as well as other aspects of certain systemic treatments in patients of Asian ethnicity. These guidelines represent the consensus opinions reached by experts in the treatment of patients with mCRC identified by the Presidents of the oncological societies of Japan (JSMO), China (Chinese Society of Clinical Oncology), Korea (Korean Association for Clinical Oncology), Malaysia (Malaysian Oncological Society), Singapore (Singapore Society of Oncology) and Taiwan (Taiwan Oncology Society). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.
Most cancer cells exhibit increased glycolysis and use this metabolic pathway for generation of ATP as a main source of their energy supply. This phenomenon is known as the Warburg effect and is ...considered as one of the most fundamental metabolic alterations during malignant transformation. In recent years, there are significant progresses in our understanding of the underlying mechanisms and the potential therapeutic implications. Biochemical and molecular studies suggest several possible mechanisms by which this metabolic alteration may evolve during cancer development. These mechanisms include mitochondrial defects and malfunction, adaptation to hypoxic tumor microenvironment, oncogenic signaling, and abnormal expression of metabolic enzymes. Importantly, the increased dependence of cancer cells on glycolytic pathway for ATP generation provides a biochemical basis for the design of therapeutic strategies to preferentially kill cancer cells by pharmacological inhibition of glycolysis. Several small molecules have emerged that exhibit promising anticancer activity in vitro and in vivo, as single agent or in combination with other therapeutic modalities. The glycolytic inhibitors are particularly effective against cancer cells with mitochondrial defects or under hypoxic conditions, which are frequently associated with cellular resistance to conventional anticancer drugs and radiation therapy. Because increased aerobic glycolysis is commonly seen in a wide spectrum of human cancers and hypoxia is present in most tumor microenvironment, development of novel glycolytic inhibitors as a new class of anticancer agents is likely to have broad therapeutic applications.
Fast radio bursts (FRBs) are millisecond-duration radio transients
of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star ...magnetospheres
or relativistic shocks far from the central energy source
. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters
or variable polarization angles in some other apparently one-off events
. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.
In order to address the present difficulty in experimentally generating the relativistic Laguerre-Gaussian laser, primarily due to damage caused to optical modulators, a high-reflectivity phase ...mirror is applied in the femtosecond petawatt laser system to generate a relativistic hollow laser at the highest intensity of 6.3 × 1019 W / cm2 for the first time. A simple optical model is used to verify that the vortex laser may be generated in this new scheme; using such a relativistic vortex laser, the hollow plasma drill and acceleration are achieved experimentally and proven by particle-in-cell simulations. With the development of the petawatt laser, this scheme opens up possibilities for the convenient production of the relativistic hollow laser at high repetition and possible hollow plasma acceleration, which is important for a wide range of applications such as the generation of radiation sources with orbital angular momentum, fast ignition for inertial confinement fusion, and jet research in the astrophysical environment.
Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin ...of cosmological FRBs is still not settled. Here we report the detection of1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref.9). These observations show irregular short-time variation ofthe Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (au; Earth-Sun distance) ofthe source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.
Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances
. It has long been speculated that magnetars are the engine powering ...repeating bursts from FRB sources
, but no convincing evidence has been collected so far
. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts
. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare
. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
We present experimental studies on ion acceleration using an 800-nm circularly polarized laser pulse with a peak intensity of 6.9×10^{19} W/cm^{2} interacting with an overdense plasma that is ...produced by a laser prepulse ionizing an initially ultrathin plastic foil. The proton spectra exhibit spectral peaks at energies up to 9 MeV with energy spreads of 30% and fluxes as high as 3×10^{12} protons/MeV/sr. Two-dimensional particle-in-cell simulations reveal that collisionless shocks are efficiently launched by circularly polarized lasers in exploded plasmas, resulting in the acceleration of quasimonoenergetic proton beams. Furthermore, this scheme predicts the generation of quasimonoenergetic proton beams with peak energies of approximately 150 MeV using current laser technology, representing a significant step toward applications such as proton therapy.
Timing observations from the Parkes 64-m radio telescope for 165 pulsars between 1990 and 2011 have been searched for period glitches. Data spans for each pulsar ranged between 5.3 and 20.8 yr. From ...the total of 1911 yr of pulsar rotational history, 107 glitches were identified in 36 pulsars. Out of these glitches, 61 have previously been reported whereas 46 are new discoveries. Glitch parameters, both for the previously known and the new glitch detections, were measured by fitting the timing residual data. Observed relative glitch sizes Δνg/ν range between 10−10 and 10−5, where ν = 1/P is the pulse frequency. We confirm that the distribution of Δνg/ν is bimodal with peaks at approximately 10−9 and 10−6. Glitches are mostly observed in pulsars with characteristic ages between 103 and 105 yr, with large glitches mostly occurring in the younger pulsars. Exponential post-glitch recoveries were observed for 27 large glitches in 18 pulsars. The fraction Q of the glitch that recovers exponentially also has a bimodal distribution. Large glitches generally have low Q, typically just a few per cent, but large Q values are observed in both large and small glitches. Observed time constants for exponential recoveries ranged between 10 and 300 d with some tendency for longer time-scales in older pulsars. Shorter time-scale recoveries may exist but were not revealed by our data which typically have observation intervals of 2-4 weeks. For most of the 36 pulsars with observed glitches, there is a persistent linear increase in
(i.e. decrease in the slow-down rate
) in the interglitch interval. Where an exponential recovery is also observed, the effects of this are superimposed on the linear increase in
. In some but not all cases, the slope of the linear recovery changes at the time of a glitch. The
values characterizing the linear changes in
are almost always positive and, after subtracting the magnetospheric component of the braking, are approximately proportional to the ratio of
and the interglitch interval, as predicted by vortex-creep models.
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