Search

KS 0 KS 0 production in two-photon collisions has been studied using a 397.6 fb-1 data sample collected with the Belle detector at the KEKB e+ e- collider. For the first time the cross sections are measured in the two-photon center-of-mass energy range between 2.4 GeV and 4.0 GeV and angular range | cos θ* | < 0.6. Combining the results with measurements of γ γ → K+ K- from Belle, we observe that the cross section ratio σ (KS 0 KS 0) / σ (K+ K-) decreases from ∼0.13 to ∼0.01 with increasing energy. Signals for the χc 0 and χc 2 charmonium states are also observed. © 2007 Elsevier B.V. All rights reserved.

The current study was carried out to define the involvement of Peroxiredoxin (Prx) II in progression of hepatocellular carcinoma (HCC) and the underlying molecular mechanism(s). Expression and function of Prx II in HCC was determined using H-ras(G12V)-transformed HCC cells (H-ras(G12V)-HCC cells) and the tumor livers from H-ras(G12V)-transgenic (Tg) mice and HCC patients. Prx II was upregulated in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg mouse tumor livers, the expression pattern of which highly similar to that of forkhead Box M1 (FoxM1). Moreover, either knockdown of FoxM1 or site-directed mutagenesis of FoxM1-binding site of Prx II promoter significantly reduced Prx II levels in H-ras(G12V)-HCC cells, indicating FoxM1 as a direct transcription factor of Prx II in HCC. Interestingly, the null mutation of Prx II markedly decreased the number and size of tumors in H-ras(G12V)-Tg livers. Consistent with this, knockdown of Prx II in H-ras(G12V)-HCC cells reduced the expression of cyclin D1, cell proliferation, anchorage-independent growth and tumor formation in athymic nude mice, whereas overexpression of Prx II increased or aggravated the tumor phenotypes. Importantly, the expression of Prx II was correlated with that of FoxM1 in HCC patients. The activation of extracellular signal-related kinase (ERK) pathway and the expression of FoxM1 and cyclin D1 were highly dependent on Prx II in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg livers. Prx II is FoxM1-dependently-expressed antioxidant in HCC and function as an enhancer of Ras(G12V) oncogenic potential in hepatic tumorigenesis through activation of ERK/FoxM1/cyclin D1 cascade.

This study was performed to develop thin layer drying equations for green rice. Thin layer drying tests of green rice were conducted at three temperature levels of 30, 40, and two relative humidity levels of 30, 50% respectively. The measured moisture ratio were fitted to the selected four drying models (Page, Thompson, Simplified diffusion and Lewis model) using stepwise multiple regression analysis. The overall drying rate increased as the drying air temperature and as relative humidity was increased, but the effect of temperature increase was dominant. Half response time (Moisture ratio

Using kaon secondary interactions in the material of the Belle detector, we search for both inclusive and exclusive production of the Θ(1540) +. We set an upper limit of 2.5% at the 90% C.L. on the ratio of the Θ(1540)+ to Λ(1520) inclusive production cross sections. We also search for the Θ(1540)+ as an intermediate resonance in the charge exchange reaction K+n→pKS 0. We set an upper limit of ΓΘ+

Black, clay-like sediments have been obtained from the area of the pigment manufacturing factories in Dongducheon city, Korea. These sediments were contaminated by heavy metals, especially chromium (700 mg/kg). Indigenous bacteria in the sediments were isolated to investigate their ability to reduce Cr(VI) to Cr(III). The enriched bacterial consortium reduced over 99% of dissolved Cr(VI) in 96 h from the onset of the experiments under anaerobic condition, while there was no change in Cr(VI) concentration until 300 h in abiotic controls. Total amount of dissolved Cr decreased simultaneously when Cr(VI) was reduced, which was likely due to precipitation of Cr(OH)3 after microbial reduction of Cr(VI) to Cr(III). Under aerobic condition, only 30% of dissolved Cr(VI) was reduced by indigenous bacteria until 900 h. The reduction of Cr(VI) did not accompany bacterial growth since the amount of protein did not show a significant change with time both in the presence and absence of O2. These indigenous bacteria may play a role in the treatment of Cr(VI)-contaminated sediments.

We have searched for τ lepton decays, τ-→Λπ- and τ-→Λπ-, that simultaneously violate the conservation of the lepton (L) and baryon (B) number using a data sample of 154 fb-1 collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. No evidence for a signal was found in either of the decay modes and we set the following upper limits for the branching fractions: B(τ-→Λπ-)

We present measurements of the branching fraction, the polarization parameters and CP-violating asymmetries in B0→D*+D *- decays using a 140 fb-1 data sample collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. We obtain B(B0→D*+D*-)=[0. 81±0.08(stat)±0.11(syst)]×10-3, R⊥=0.19±0. 08(stat)±0.01(syst), R0=0.57±0.08(stat)±0.02(syst), S=-0.75±0.56(stat)±0.12(syst) and A=-0.26±0.26(stat) ±0.06(syst). Consistency with Standard Model expectations is also discussed.

In order to investigate the extent and degree of heavy metal contamination in soils and sediments influenced by past mining activities, and to estimate the effects of indigenous bacteria on Cd speciation and bioremoval efficiency in sediments according to the various environmental conditions, tailings, soils, waters and sediments were collected from the Hwacheon Au-Ag-Pb-Zn mine in Korea. Elevated levels of metals, i.e., 29 As mg/kg, 30 Cd mg/kg, 261 Cu mg/kg, 601 Pb mg/kg and 3128 Zn mg/kg were found in sediments. High concentrations of As and other heavy metals in soils, waters and sediments were found near the tailings piles. From the results of sequential extraction analyses with tailings and soils, a high proportion of Cd is present as non-residual fractions. This indicates that Cd is more mobile and bioavailable than Cu, Pb and Zn. For seasonal variation, the concentrations of As and other heavy metals were much more elevated in soils collected before rainy season than after rainy season. To estimate the bioremoval efficiency for Cd, bacteria which can adsorb Cd were isolated from sediments in this area. Microorganisms in sediments can alter the mobility of heavy metals and bacteria can leach heavy metals from sediments, adsorb them on their cell wall and accumulate them within an intracellular matrix. From the metal sorption tests with indigenous bacteria, the bioremoval efficiency of Cd in Cd single solution (10 ppm) was more than 90%. As well, the isolated bacterial strains exhibited a preferential metal sorption , i.e., Cd > Pb > Zn for single metal solutions and Pb > Cd > Zn for the mixed metal solutions. Therefore, the use of some microorganisms to remove heavy metals from contaminated sediments may represent an innovative purification process.

We report the observation of B0 decays to the K+π-π0 final state using a data sample of 78 fb-1 collected by the Belle detector at the KEKB e+e- collider. With no assumptions about intermediate states in the decay, the branching fraction is measured to be (36.6-4.3+4.2±3.0)×10-6. We also search for B decays to intermediate two-body states with the same K+π-π0 final state. Significant B signals are observed in the ρ(770)-K+ and K*(892)+π- channels, with branching fractions of (15.1-3.3-1.5-2.1+3.4+1.4+2.0)×10-6 and (14.8-4.4-1.0-0.9+4.6+1.5+2.4) ×10-6, respectively. The first error is statistical, the second is systematic and the third is due to the largest possible interference. Contributions from other possible two-body states will be discussed. No CP asymmetry is found in the inclusive K+π-π0 or ρ-K+ modes, and we set 90% confidence level bounds on the asymmetry of -0.12

An experimental search for WIMP using CsI(Tl) crystals(KIMS) is being prepared at the underground laboratory, Cheongpyung, Korea. Characteristics and internal background of CsI(Tl) crystal have been investigated in detail to develop highly sensitive detector for WIMP search. The background at the underground laboratory is measured and shielding design has been done with an optimization with a MC study. The result of detector development and prospect of KIMS experiment is reported.

Phosphatidylinositol 3-kinase (PI 3-kinase) and mitogen-activated protein kinases (MAPKs) have been implicated in diverse cellular functions, including proliferation, migration, and survival. In this study, we examined the involvement of these kinases in osteoclast differentiation by employing specific inhibitors of the kinases. The osteoclast differentiation was assessed in three different culture systems: a coculture of mouse bone marrow cells with mouse calvarial osteoblasts, a mouse bone marrow cell culture in the presence of receptor activator of NF-kappaB ligand (RANKL) and macrophage-colony stimulating factor (M-CSF), and a culture of bone-resident osteoclast precursor cells driven by RANKL and M-CSF. LY294002, a specific inhibitor of PI 3-kinase, potently inhibited osteoclast differentiation in all culture systems when assessed by both tartrate-resistant acid phosphatase (TRAP) staining and dentine resorption assays. Inhibition of p38 MAPK by SB202190 resulted in a strong suppression in the exogenous RANKL dependent mouse bone marrow and bone resident precursor cell cultures. Another MAPK pathway inhibitor (PD98059), which blocks the activation of extracellular signal-regulated kinase (ERK) by inhibiting the upstream kinase MAPK-ERK kinase (MEK) 1, exerted an inhibitory effect on osteoclast differentiation only at the highest concentration tested (30 micromol/L) in many cases. Whether the signaling pathways involving these kinases are activated by RANKL was also examined. The RANKL-stimulated phosphorylation of Akt, a downstream target of PI 3-kinase, and that of ERK were observed. RANKL also stimulated the activity of p38. These results suggest that PI 3 kinase, p38, and ERK play roles in osteoclast differentiation, at least in part, by participating in RANKL signaling.

A single phase, nanocrystalline perovskite PZT powder has been successfully derived from a mixture of oxides via a mechanical activation route. Unlike in the conventional solid state reaction, the perovskite PZT phase was first triggered and then progressively formed without passing through the intermediate PT and PZ phases with increasing degree of mechanical activation. Similarly, the formation of a single phase PZT of perovskite structure can be completed in a partially activated mixture of oxide powders when heated at an elevated temperature, also without involving PT and PZ as transitional phases. Dense PZT (>95% theoretical density) with excellent dielectric properties was obtained when the mechanically activated powders are sintered at 1150°C. The relative density and dielectric properties of sintered PZT were improved when the formation of perovskite phase is completed by the mechanical activation.

Vitamin D-deactivating enzyme CYP24A1 had controversial effects on prostate cancer risk; the genetic study also showed the controversial results. Therefore, we identified the relationships between polymorphisms in CYP24A1 and prostate cancer in a Korean cohort.We evaluated the association between 21 single-nucleotide polymorphisms (SNPs) in the CYP24A1 and prostate cancer in Korean men (272 prostate cancers and 173 controls). BPH patients with high PSA or abnormal digital rectal examination who underwent negative prostate biopsy were enrolled in the control group. Twenty-one SNPs in the CYP24A1 were selected from the International HapMap database and the NCBI database with calculation of minor allele frequency and linkage disequilibrium, preferably including the SNPs that were nonsynonymous and located within exons. We also investigated the association between 21 SNPs in the CYP24A1 gene and known clinical characteristics, such as the PSA level, clinical stage, pathological stage and Gleason score.The statistical analysis suggested that five CYP24A1 sequence variants (rs2248461-odds ratio (OR): 0.63, rs2248359-OR: 0.65, rs6022999-OR: 0.65, rs2585428-OR: 0.46, rs4809959-OR: 0.52) had a significant association with prostate cancer risk after multiple comparisons by a method of false discovery rate. Logistic analyses of the CYP24A1 polymorphisms with several prostate cancer-related factors showed that several SNPs were significant: four SNPs to PSA level, three to clinical stage, two to pathological stage and two SNPs to the Gleason score.The results of this study suggest that some CYP24A1 gene polymorphisms might be associated with the risk of prostate cancer in Korean men. Five CYP24A1 sequence variants showed the significance to predict prostate cancer, and several SNPs of CYP24A1 gene had an important finding to predict prostate cancer-related factors. However, these results should be validated in future large-scale studies.

Some degree of physiological subepithelial opacification can be photographed in all human corneas. In most patients undergoing refractive treatment with an excimer laser further opacification occurs.

Citrus unshiu (Satsuma mandarin, SM) is a citrus fruit the peel of which has been used as a traditional Chinese medicine to treat common cold, relieve exhaustion, and cancer. In this study, we examined how effectively the content and peel extracts of SM can suppress cancer growth. The mechanism underlying cancer-suppressing properties of SM was investigated in tumor-bearing mice with renal carcinoma cell, Renca.Effectiveness of SM in tumor suppression was evaluated by measuring size of tumor mass in tumor-bearing mice treated with various doses of SM content and peel extracts. Proliferation of tumor cells and splenocytes was determined by MTT assay and [³H]TdR uptake, respectively. Relevant immunological mechanisms were chased by assaying cytokines including TGF-β, IL-6, IFN-γ, and TNF-α by ELISA.The content and peel extracts of SM inhibited the growth of tumor cells in tumor-bearing mice. Especially, average tumor volume of two groups treated with 3 and 30 mg peel extracts per mouse weight (kg) were significantly decreased to 52.32% (p0.05) and 68.72% (p0.01), respectively. To identify tumor regression mechanism, anti-tumor cytokines measured in Con A-activated splenocytes from tumor-bearing mice. IFN-γ was increased in both of the peel extract-treated groups, while TNF-α, which had been decreased by tumor growth, was rescued to the normal level in SM content and peel extracts-treated groups. However, SM content and peel extracts did not inhibit proliferation and tumor-proliferative cytokines including TGF-β and IL-6 production of tumor cells.These results indicate that SM content and peel extracts have anti-tumor properties in the tumor-bearing murine model. The mechanism underlying the anti-tumor effects of SM extracts is strongly suggested to be via boosting cytokines such as IFN-γ and TNF-α, enhancing immune-mediated anti-tumor properties.

Bambusae Caulis in Taeniam (BC) was known as traditional herbal medicine with anti-inflammatory property in the Orient.Allergic asthma is inflammatory disease of airways associated with enhanced T helper (Th) 2 lymphocytes responses to allergens, leading to eosinophilic infiltration and elevated serum IgE levels. Although there were some studies that BC extract had an anti-inflammatory property, there was no study on asthma. In present study, we investigated the suitability of BC extract as a therapeutic candidate in the treatment of allergic airway disease in ovalbumin-induced asthma model.Balb/C mice (female, 6 weeks old) were treated by ovalbumin sensitization and nebulization, and used as asthma model. The number of eosinophil in bronchoalveolar lavage (BAL) fluid and the degree of eosinophila were investigated by hematoxylin and eosin stain and the infiltration of inflammatory cells into lung tissues was examined by staining by hematoxylin and eosin solution. The levels of interleukin (IL)-4 in BAL fluid, immunoglobulin E (IgE) in serum, interferon (IFN)-gamma and IL-4 production in splenocyte culture from Balb/C mice (not treated, 6 weeks old) that incubated with or without BC extract for 48 h were determined by enzyme-linked immunosorbent assay.The level of eosinophils was decreased by treatment of the animals with BC extract (40 mg/kg) and correspondingly, a significantly lowered degree of eosinophila was also reported (p0.01). In lung tissue, BC extract reduced the increased immune cell infiltration induced by OVA (p0.05). Furthermore, the levels of IL-4 and IgE in BAL fluid or serum up-regulated by OVA was decreased by BC extract. Finally, IFN-gamma production was significantly increased (p0.01), while IL-4 production significantly decreased (p0.01), after treatment of the culture supernatants of splenocytes with BC extract.These results indicated that BC extract reduces OVA-induced airway inflammation and Th 2 response in mice, suggesting that BC extract can be a therapeutic candidate for allergic airway disease, including asthma.

Background/Aims: Lymph node metastasis is the most important point to consider when deciding on the modality of resection in patients with early gastric cancer. This study was conducted to evaluate the learning curve for identification of sentinel lymph nodes in patients with gastric cancer. Methods: The investigators included the results from 2 prospective series of sentinel lymph node mapping. Cumulative sum (CUSUM) analysis was performed to assess the learning curves for identification of sentinel lymph nodes at CUSUM target success rates of 95%. Results: One surgeon performed 135 sentinel lymph node mappings for 2 prospective series. The success rate exceeded 90%. The learning period for gastric cancer sentinel node mapping was calculated to be 26 cases for achieving a 95% success rate. Multiple logistic regression analysis for successful detection of sentinel nodes showed that surgical experience of sentinel lymph node mapping was an independent factor for successful detection of sentinel nodes. Conclusions: This study suggests that the learning period for identification of sentinel lymph nodes in gastric cancer would be 26 cases. In clinical trials for gastric cancer with sentinel lymph node mapping, the learning curve should be considered to minimize bias due to surgical factors.

Crude and/or refined oil products accidentally released into coastal or oceanic waters will result in the formation of surface slicks that create hazards to sea life. Such releases can be mitigated by the use of chemical dispersants under appropriate conditions. However, the potential performance of these agents for dispersing oil in marine situations must be known prior to their use at spill sites. Therefore, reliable methods for evaluating and quantifying performance measurements for dispersants are necessary so that dispersant performance can be better estimated. An important component in any testing method of candidate dispersants (as well as other spill treating chemicals) is the precision associated with repeated measurements made with the method. This paper presents a statistical evaluation of results from tests that were conducted to evaluate the performance of different dispersants with a number of laboratory test methods. The overall test design for the study included three test methods, two to five test oils (depending on the method evaluated), three commercially available dispersants, and analytical measurements at three spectrophotometric wavelengths. The evaluation was conducted in support of the research program of EPA`s Releases Control Branch, Risk Reduction Engineering Laboratory to support the EPA work group concerned with Subpart Jmore » (Dispersant Effectiveness and Toxicity) of the National Contingency Plan (NCP). A major goal of the parent study on which this work is based has been to estimate the variability or precision for repeated measurements with test methods and provide the best estimate of this precision for the proposed revision of Subpart J of the NCP for dispersant performance testing.« less

We examined the effects of NaCl and glucose on cold-set ovalbumin gelation. Cold-set gels were prepared by adding glucono-delta-lactone (GDL) to a 2% heated ovalbumin solution. For the gel prepared from ovalbumin heat-denatured with NaCl and glucose, the gel with 10 mM NaCl was most transparent and had high gel strength. Its maximum complex shear modulus (G*) and turbidity were 2.5 times greater and 3 times lower, respectively, than those of the gel without NaCl. The turbidity of the gel with the higher NaCl content increased steeply after the addition of GDL and did not change during the experimental period. The maximum G* of the gel exhibited positive correlations with the molar mass, radius, and surface hydrophobicity of soluble aggregates and the NaCl content, but the turbidity exhibited negative correlations with these factors. The presence of glucose did not significantly affect the turbidity or rheological properties of the gel. For the gel prepared by adding NaCl and glucose with GDL, the presence of glucose did not affect the turbidity, but the maximum G* decreased in inverse proportion to the glucose content. The turbidity of the gel with higher NaCl content (>or= 50 mM) was the greatest among all samples, and the increased turbidity was maintained throughout the measurements. The gels with 50 and 100 mM NaCl exhibited thixotropy during shearing at a constant shear rate. Therefore, the presence of NaCl and glucose during cold gelation could facilitate the preparation of cold-set gels having various properties for food applications.

We describe a photonic quantum ring (PQR) laser device of three dimensional toroidal whispering gallery cavity. We have succeeded in fabricating the first genuine mega-pixel laser chips via regular semiconductor technology. This has been realized since the present injection laser emitting surface-normal dominant 3D whispering gallery modes (WGMs) can be operated CW with extremely low operating currents (μA-nA per pixel), together with the lasing temperature stabilities well above 140 deg C with minimal redshifts, which solves the well-known integration problems facing the conventional VCSEL. Such properties unusual for quantum well lasers become usual because the active region, involving vertically confining DBR structure in addition to the 2D concave WGM geometry, induces a 'photonic quantum ring (PQR)-like' carrier distribution through a photonic quantum corral effect. A few applications of such mega-pixel PQR chips are explained as follows: (A) Next-generation 3D semiconductor technologies demand a strategy on the inter-chip and intra-chip optical interconnect schemes with a key to the high-density emitter array. (B) Due to mounting traffic problems and fatalities ITS technology today is looking for a revolutionary change in the technology. We will thus outline how 'SLEEP-ITS' can emerge with the PQR's position-sensing capability. (C) We describe a recent PQR 'hole' laser of convex WGM: Mega-pixel PQR 'hole' laser chips are even easier to fabricate than PQR 'mesa' lasers. Genuine Laguerre-Gaussian (LG) beam patterns of PQR holes are very promising for biocell manipulations like sorting mouse myeloid leukemia (M1s) cells. (D) Energy saving and 3D speckle-free POR laser can outdo LEDs in view of red GaAs and blue GaN devices fabricated recently.

We have succeeded in fabricating one mega (M) photonic quantum ring (PQR) hole laser array. Each pixel of the PQR hole laser chip has very low transparent (80 nA) and threshold (300 nA) currents due to photonic crystal-like cooperative effects. The envelope of the multi-peak PQR hole laser spectrum is typically about 2 nm wide.

We report on a new, simple, effective and fast cell sorting method for massive micro-manipulation of biological cells or small particles in microfluidic channel involving a sorter-on-mega photonic quantum ring (PQR) hole laser chip scheme.

We report on the first observation of "hole" whispering gallery lasers from semiconductor microcavities with three dimensional optical confinement, with thresholds potentially reducible to micro-to-nano ampere regimes If the device size grows over a critical diameter, the quantum ring whispering gallery then begins to disappear. However, cooperative small hole laser arrays, exhibiting photonic crystal structure properties, avoid the criticality and open a possibility of constructing practical high-density electro-pumped emitter arrays.

The PQR laser with ultra-low threshold current and sharp discrete multi-mode properties outdo conventional LEDs. We have fabricated 16times16 mesa type red PQR laser arrays at lambda = 610 nm and confirmed the superiority in luminous efficiency of PQR arrays to the conventional LEDs. We also present blue PQR laser arrays from GaN structures, which are very promising for display applications as well as low power high efficiency solid state lighting.

Some possible approaches to the use of neural networks for interpreting sensor, and particular spectral type, data are sketched. It is demonstrated how the structure of the neural network can be chosen to provide the capacity to fall back to the linear case when appropriate. An approach to the problem of underdetermined systems, based on adding random Gaussian noise to prevent the neural network from being locked into a local minimum, is presented. >

The authors demonstrate that a combined architecture of linear and nonlinear artificial neural networks offers many advantages over the conventional multilayer feedforward networks and the conventional biased regression methods for the modeling of spectroscopic process data. This direct linear feedthrough (DLF) network is an especially useful tool for modeling process data when the true linear or nonlinear functionality of the system is not known. By just looking at the linear and nonlinear contributions of this DLF network, it is possible to tell if the data are purely linear or nonlinear. For the learning algorithm, sequential quadratic programming improves the training time of the neural network by 2-3 orders of magnitude compared to that of the back-propagation method. The authors also suggest that when the number of data samples is small compared to the size of the network, the risk of under-representing or overfitting the available data can be avoided by using the leave-one-out cross validation technique. >

We have studied the response of Tl-doped and Na-doped CsI crystals to nuclear recoils and $\gamma$'s below 10 keV. The response of CsI crystals to nuclear recoil was studied with mono-energetic neutrons produced by the $^3$H(p,n)$^3$He reaction. This was compared to the response to Compton electrons scattered by 662 keV $\gamma$-ray. Pulse shape discrimination between the response to these $\gamma$'s and nuclear recoils was studied, and quality factors were estimated. The quenching factors for nuclear recoils were derived for both CsI(Na) and CsI(Tl) crystals., Comment: 21pages, 14figures, submitted to NIMA