Abstract
The objectives of this work using
P
haseolus vulgaris
were to examine whether the light spectrum incident on mature primary leaves (
PL
s) is related to leaf‐to‐leaf systemic regulation of ...developing trifoliate leaves (
TL
s) in photosynthetic characteristics, and to investigate the relative importance of spectrum and photosynthetic photon flux density (
PPFD
) in light‐induced systemic regulation. Systemic regulation was induced by altering
PPFD
and the spectrum of light incident on
PL
s using a shading treatment and lighting treatments including either white, blue, green or red light‐emitting diodes (
LED
s). Photosynthetic characteristics were evaluated by measuring the light‐limited and light‐saturated net photosynthetic rates and the amounts of nitrogen (
N
), chlorophyll (
C
hl) and ribulose‐1,5‐bisphosphate carboxylase/oxygenase (
R
ubisco;
EC
4.1.1.39). Shading treatment on
PL
s decreased the amounts of
N
,
C
hl and
R
ubisco of
TL
s and tended to decrease the photosynthetic rates. However, we observed no systemic effects induced by the light spectrum on
PL
s in this study, except that a higher amount of
R
ubisco of
TL
s was observed when the
PL
s were irradiated with blue
LED
s. Our results imply that photoreceptors in mature leaves have little influence on photosynthetic rates and amounts of
N
and
C
hl of developing leaves through systemic regulation, although the possibility of the action of blue light irradiation on the amount of
R
ubisco cannot be ruled out. Based on these results, we concluded that the light spectrum incident on mature leaves has little systemic effect on developing leaves in terms of photosynthetic characteristics and that the light‐induced systemic regulation was largely accounted for by
PPFD
.
Autophagy, or programmed cell death type II, is one of the responses of cancer cells to various therapies, including ionizing radiation. Recently, we have shown that radiation induces autophagy, but ...not apoptosis, in various malignant glioma cell lines. Autophagy is mainly regulated by the mammalian target of rapamycin (mTOR) pathway. The Akt/mTOR pathway also mediates oncogenesis and radioresistance. Thus, we hypothesized that inhibiting this pathway has both an anticancer and radiosensitizing effect by activating autophagy. The purpose of our study was therefore to determine whether and by which mechanisms an Akt inhibitor, 1L-6-hydroxymethyl-chiro-inositol 2(R)-2-O-methyl-3-O-octadecylcarbonate, had anticancer and radiosensitizing effects on malignant glioma U87-MG and radioresistant U87-MG cells with a consistitutively active form of epidermal growth factor receptor (U87-MGDeltaEGFR). Treatment with the Akt inhibitor successfully inhibited Akt activity and reduced cell viability in both cell lines. In terms of the mechanism, the Akt inhibitor decreased phosphorylated p70S6 kinase, a downstream target of Akt, and induced autophagy, but not apoptosis. Furthermore, the Akt inhibitor radiosensitized both U87-MG and U87-MGDeltaEGFR cells by enhancing autophagy. Specific inhibition of Akt using the dominant-negative Akt plasmid also resulted in enhanced radiation-induced autophagy. In conclusion, an Akt inhibitor showed anticancer and radiosensitizing effect on U87-MG and U87-MGDeltaEGFR cells by inducing autophagy. Thus, Akt inhibitors may represent a promising new therapy as a single treatment or used in combination with radiation for malignant gliomas, including radioresistant ones that express DeltaEGFR.
Slow magnetic relaxation and the Fe ion stoichiometry were investigated in spin and charge frustrated system YbFe2O4. DC susceptibility, AC susceptibility, aging process and electron diffraction ...observation were carried out on nano order sized YbFe2O4 single-phase powders with the Fe/Yb=2.00, 2.02, and 2.04 ratios. The variation of the cluster glass behavior was studied in relation between the magnetic relaxation and the various chemical compositions. With the increase of the Fe/Yb ratios, the magnetic coherence length increased and the magnetic aging time goes slow down. The observed critical slowing down of the glassy fluctuation is interpreted by the development of the spin cluster size. This indicates that the spin glass like property of this material arises from the competition between various sized magnetic domains having ferrimagnetic moments. Additionally, electron diffraction experiments showed that the increase of Fe/Yb ratios from Fe/Yb=2.00 enhances the development of the charge ordering coherence in triangular lattice. This study shows that the measurement of magnetic fluctuation for nano order sized particles gives the essential information about the spin cluster fluctuation in RFe2O4.
•Investigations of electromagnetic ordering state in spin and charge frustrated system.•Carried out using Fe stoichiometry controlled nano order sized YbFe2O4 powders.•Spin and charge coherence length increased as Fe/Yb ratios larger.•The glass behavior became ineffectual with developing electromagnetic ordering.
We have designed and implemented an SFQ programmable clock generator (PCG), which can generate the variable number of SFQ pulses according to its internal state. The PCG is composed of an SFQ ring ...oscillator, a control circuit which counts up the number of SFQ pulses and stops the operation of the ring oscillator, and a decoder which defines the initial state of the control circuit. The PCG can generate the variable number of SFQ pulses ranging from 2 to 2
N
, where
N is the number of T flip-flops in the control circuit. The oscillation frequency of the PCG is designed to be ranging from 6.2 to 18.8 GHz. In this study, we have implemented a PCG generating SFQ pulses ranging from 2 to 2
4 using a cell-based design methodology and confirmed its correct functionality.
Formation mechanism of twin boundaries in silicon multicrystals during crystal growth was investigated by using in-situ observation of the growth interface and following characterization of ...microstructures of the grown crystal. The crystal growth experiments were performed under two different conditions, which are constant cooling rate and intentionally changed crystal growth rate. Under both the conditions, twin boundaries were more frequently formed when the growth rate drastically increased than when the growth rate was constant in high value. Based on these new findings, formation mechanism of twin boundaries are discussed in terms of formation energy.
Although the functions associated with differentiation are thought to be suppressed when cells proliferate, recent studies have shown that several mitogens can stimulate functions such as protein ...production under certain physiological conditions. Hepatocyte growth factor (HGF) is now considered to be a pluripotent factor and has been shown to stimulate the differentiated functions of hepatocytes, as well as their proliferation. The use of HGF for the treatment of liver disease, especially hepatic failure, has been suggested.
Because patients with decompensated liver cirrhosis have decreased plasma concentrations of branched-chain amino acids (BCAAs), many investigations in laboratory animals and patients have been designed to demonstrate the benefits of supplementation of BCAAs on the hepatic metabolism of proteins. However, the mechanisms involved in the specific actions of BCAAs remain to be elucidated. Amino acids are molecules that modulate numerous cellular functions. BCAAs are known to influence gene expression, cellular metabolism, amino acid transport, and protein turnover.
In this paper, we show the potential of BCAAs for stimulating HGF synthesis in the liver and discuss the possibility that BCAAs stimulate protein production by hepatocytes through the induction of HGF.
We fabricated Si-based solar cell with stacked Ge islands grown via the Stranski–Krastanov growth mode in the intrinsic layer of
pin diodes. The onset of the external quantum efficiency in the near ...infrared regime was extended up to approximately 1.4 μm for the solar cells with stacked Ge islands. The quantum efficiency was found to increase with increasing number of stacking, showing that a part of electron–hole pairs generated within Ge islands was separated by the internal electric field and contributed to the photocurrent. Increase of the processing temperature for the impurity diffusion was found to bring blue-shift of the band gap through the intermixing of Si and Ge as well as the deformation of Ge islands. Therefore, low-temperature process was suggested to be necessary for further enhancement of quantum efficiency in the near infrared regime.
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