Early (<<0.3 day) R-band light curve of the optical afterglow of GRB030329

We observed the optical afterglow of the bright gamma-ray burst GRB030329 on the nights of 2003 March 29, using the Kiso observatory (the University of Tokyo) 1.05 m Schmidt telescope. Data were taken from March 29 13:21:26 UT to 17:43:16 (0.072 to 0.253 days after the burst), using an $Rc$-band filter. The obtained $Rc$-band light curve has been fitted successfully by a single power law function with decay index of $0.891\pm0.004$. These results remain unchanged when incorporating two early photometric data points at 0.065 and 0.073 days, reported by Price et al.(2003) using the SSO 40 inch telescope, and further including RTT150 data (Burenin et al. 2003) covering at about 0.3 days. Over the period of 0.065-0.285 days after the burst, any deviation from the power-law decay is smaller than $\pm$0.007 mag. The temporal structure reported by Uemura et al. (2003) does not show up in our $R$-band light curve.Comment: 9 pages, 2 figures, 1 table, accepted for publication in ApJ

Validation and study of different parameters in the simulation of diagnostic X-ray spectra using the MCNPX code

In radiology, knowing the X-ray spectrum characteristics makes it possible to estimate the absorbed dose in the patient and to improve image quality. In this study, an X-ray generator was proposed using the MCNPX code and to validate it, the simulated spectrum was compared to the data provided from AAPM Task Group 195, which resulted in a percentage difference of 8.7%. Furthermore, several X-ray spectra were generated and compared to the spectra obtained from commercially available softwares as xpecgen and SpekCalc. The percentage differences were of the order of 13% in comparison with SpekCalc and 8% with xpecgen. The major differences obtained between those spectra were concentrated in the region of characteristic peaks, independently if variations in electron beam energy, target angle or filtration thickness were performed

Precise Control of Band Filling in NaxCoO2

Electronic properties of the sodium cobaltate NaxCoO2 are systematically studied through a precise control of band filling. Resistivity, magnetic susceptibility and specific heat measurements are carried out on a series of high-quality polycrystalline samples prepared at 200 C with Na content in a wide range of 0.35 =< x =< 0.70. It is found that dramatic changes in electronic properties take place at a critical Na concentration x* that lies between 0.58 and 0.59, which separates a Pauli paramagnetic and a Curie-Weiss metals. It is suggested that at x* the Fermi level touches the bottom of the a1g band at the gamma point, leading to a crucial change in the density of states across x* and the emergence of a small electron pocket around the gamma point for x > x*.Comment: 4 pages, 5 figures, submitted to J. Phys. Soc. Jp

Topical Review: Development of overgrown semi-polar GaN for high efficiency green/yellow emission

The most successful example of large lattice-mismatched epitaxial growth of semiconductors is the growth of III-nitrides on sapphire, leading to the award of the Nobel Prize in 2014 and great success in developing InGaN-based blue emitters. However, the majority of achievements in the field of III-nitride optoelectronics are mainly limited to polar GaN grown on c-plane (0001) sapphire. This polar orientation poses a number of fundamental issues, such as reduced quantum efficiency, efficiency droop, green and yellow gap in wavelength coverage, etc. To date, it is still a great challenge to develop longer wavelength devices such as green and yellow emitters. One clear way forward would be to grow III-nitride device structures along a semi-/non-polar direction, in particular, a semi-polar orientation, which potentially leads to both enhanced indium incorporation into GaN and reduced quantum confined Stark effects. This review presents recent progress on developing semi-polar GaN overgrowth technologies on sapphire or Si substrates, the two kinds of major substrates which are cost-effective and thus industry-compatible, and also demonstrates the latest achievements on electrically injected InGaN emitters with long emission wavelengths up to and including amber on overgrown semi-polar GaN. Finally, this review presents a summary and outlook on further developments for semi-polar GaN based optoelectronics

Successful Treatment for Hepatic Encephalopathy Aggravated by Portal Vein Thrombosis with Balloon-Occluded Retrograde Transvenous Obliteration

This report presents the case of a 78-year-old female with hepatic encephalopathy due to an inferior mesenteric venous-inferior vena cava shunt. She developed hepatocellular carcinoma affected by hepatitis C virus-related cirrhosis and underwent posterior sectionectomy. Portal vein thrombosis developed and the portal trunk was narrowed after hepatectomy. Portal vein thrombosis resulted in high portal pressure and increased blood flow in an inferior mesenteric venous-inferior vena cava shunt, and hepatic encephalopathy with hyperammonemia was aggravated. The hepatic encephalopathy aggravated by portal vein thrombosis was successfully treated by balloon-occluded retrograde transvenous obliteration via a right transjugular venous approach without the development of other collateral vessels

Validation of graft and standard liver size predictions in right liver living donor liver transplantation

Purpose: To assess the accuracy of a formula derived from 159 living liver donors to estimate the liver size of a normal subject: standard liver weight (g) = 218 + body weight (kg) × 12.3 + 51 (if male). Standard liver volume (SLV) is attained by a conversion factor of 1.19 mL/g. Methods: The total liver volume (TLV) of each of the subsequent consecutive 126 living liver donors was determined using the right liver graft weight (RGW) on the back table, right/left liver volume ratio on computed tomography, and the conversion factor. The estimated right liver graft weight (ERGW) was determined by the right liver volume on computed tomography (CT) and the conversion factor. SLV and ERGW were compared with TLV and RGW, respectively, by paired sample t test. Results: Donor characteristics of both series were similar. SLV and TLV were 1,099.6 ± 139.6 and 1,108.5 ± 175.2 mL, respectively, (R 2 = 0.476) (p = 0.435). The difference between SLV and TLV was only -8.9 ± 128.2 mL (-1.0 ± 11.7%). ERGW and RGW were 601.5 ± 104.1 and 597.1 ± 102.2 g, respectively (R 2 = 0.781) (p = 0.332). The conversion factor from liver weight to volume for this series was 1.20 mL/g. The difference between ERGW and RGW was 4.3 ± 49.8 g (0.3 ± 8.8%). ERGW was smaller than RGW for over 10% (range 0.21-40.66 g) in 18 of the 126 donors. None had the underestimation of RGW by over 20%. Conclusion: SLV and graft weight estimations were accurate using the formula and conversion factor. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

Diverse basis of β-catenin activation in human hepatocellular carcinoma: Implications in biology and prognosis

Aim: β-catenin signaling is a major oncogenic pathway in hepatocellular carcinoma (HCC). Since β-catenin phosphorylation by glycogen synthase kinase 3β (GSK3β) and casein kinase 1ϵ (CK1ϵ) results in its degradation, mutations affecting these phosphorylation sites cause β-catenin stabilization. However, the relevance of missense mutations in non-phosphorylation sites in exon 3 remains unclear. The current study explores significance of such mutations in addition to addressing the clinical and biological implications of β-catenin activation in human HCC. Methods: Gene alteration in exon3 of CTNNB1, gene expression of β-catenin targets such as glutamate synthetase (GS), axin2, lect2 and regucalcin (RGN), and protein expression of β-catenin were examined in 125 human HCC tissues. Results: Sixteen patients (12.8%) showed conventional missense mutations affecting codons 33, 37, 41, and 45. Fifteen additional patients (12.0%) had other missense mutations in codon 32, 34, and 35. Induction of exon3 mutation caused described β-catenin target gene upregulation in HCC cell line. Interestingly, conventional and non-phosphorylation site mutations were equally associated with upregulation of β-catenin target genes. Nuclear localization of β-catenin was associated with poor overall survival (p = 0.0461). Of these patients with nuclear β-catenin localization, loss of described β-catenin target gene upregulation showed significant poorer overall survival than others (p = 0.0001). Conclusion: This study suggests that both conventional and other missense mutations in exon 3 of CTNNB1 lead to β-catenin activation in human HCC. Additionally, the mechanism of nuclear β-catenin localization without upregulation of described β-catenin target genes might be of clinical importance depending on distinct mechanism

Mucin-hypersecreting bile duct neoplasm characterized by clinicopathological resemblance to intraductal papillary mucinous neoplasm (IPMN) of the pancreas

<p>Abstract</p> <p>Background</p> <p>Although intraductal papillary mucinous neoplasm (IPMN) of the pancreas is acceptable as a distinct disease entity, the concept of mucin-secreting biliary tumors has not been fully established.</p> <p>Case presentation</p> <p>We describe herein a case of mucin secreting biliary neoplasm. Imaging revealed a cystic lesion 2 cm in diameter at the left lateral segment of the liver. Duodenal endoscopy revealed mucin secretion through an enlarged papilla of Vater. On the cholangiogram, the cystic lesion communicated with bile duct, and large filling defects caused by mucin were observed in the dilated common bile duct. This lesion was diagnosed as a mucin-secreting bile duct tumor. Left and caudate lobectomy of the liver with extrahepatic bile duct resection and reconstruction was performed according to the possibility of the tumor's malignant behavior. Histological examination of the specimen revealed biliary cystic wall was covered by micropapillary neoplastic epithelium with mucin secretion lacking stromal invasion nor ovarian-like stroma. The patient has remained well with no evidence of recurrence for 38 months since her operation.</p> <p>Conclusion</p> <p>It is only recently that the term "intraductal papillary mucinous neoplasm (IPMN)," which is accepted as a distinct disease entity of the pancreas, has begun to be used for mucin-secreting bile duct tumor. This case also seemed to be intraductal papillary neoplasm with prominent cystic dilatation of the bile duct.</p

Periprostatic fat measured on computed tomography as a marker for prostate cancer aggressiveness

Contains fulltext : 89797.pdf (publisher's version ) (Closed access)OBJECTIVE: Several reports found that obesity was associated with prostate cancer (PC) aggressiveness among men treated with radical prostatectomy or radiotherapy. Studies concerning this issue have basically relied on body mass index (BMI), as a marker for general obesity. Because visceral fat is the most metabolic active fat, we sought to evaluate if periprostatic fat measured on a computed tomography (CT) is a better marker than BMI to predict PC aggressiveness in a Dutch population who underwent brachytherapy for localized PC. PATIENTS AND METHODS: Of the 902 patients who underwent brachytherapy, 725 CT scans were available. Subcutaneous fat thickness (CFT), periprostatic fat area (cm(2)) and fat-density (%) were determined on the CT scan. Patients were stratified into three groups: 75 percentile of the fat-density. Associations between the three fat-density subgroups and BMI and PC aggressiveness were examined. RESULTS: 237 patients were classified as having normal weight (37.2%), 320 as overweight (50.2%) and 80 as obese (12.6%). There was a strong significant association between BMI and fat-density and CFT. The strongest correlation was seen between BMI and CFT (Pearson r coefficient = 0.71). Logistic regression analysis revealed no statistically significant association between the different fat measurements and the risk of having a high-risk disease. CONCLUSIONS: Periprostatic fat and fat-density as measured with CT were not correlated with PC aggressiveness in patients receiving brachytherapy. However, 31% of the patients with a normal BMI had a fat-density of >75 percentile of the periprostatic fat-density.01 december 201