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Purpose It was reported that individual heterogeneity among malignancies (IHAM) might correlate well to the prognosis of lung cancer; however, seldom radiomic study is on this field. Standard deviation (SD) in statistics could scale average amount of variability of a variable; therefore, we used SD of CT feature (FeatureSD) among primary tumor and malignant lymph nodes (LNs) in an individual to represent IHAM, and its prognostic ability was explored. Methods The enrolled patients who had accepted PET/CT scans were selected from our previous study (ClinicalTrials.gov, NCT03648151). The patients had primary tumor and at least one LN, and standardized uptake value of LN higher than 2.0 and 2.5 were enrolled as the cohort 1 (n = 94) and 2 (n = 88), respectively. FeatureSD from the combined or thin-section CT were calculated among primary tumor and malignant LNs in each patient, and were separately selected by the survival XGBoost method. Finally, their prognostic ability was compared to the significant patient characteristics identified by the Cox regression. Results In the univariate and multivariate Cox analysis, surgery, target therapy, and TNM stage were significantly against OS in the both cohorts. In the survival XGBoost analysis of the thin-section CT dataset, none FeatureSD could be repeatablely ranked on the top list of the both cohorts. For the combined CT dataset, only one FeatureSD ranked in the top three of both cohorts, but the 3 significant factors in the Cox regression were not even on the list. Both in the cohort 1 and 2, C-index of the model composed of the 3 factors could be improved by integrating the continuous FeatureSD; furthermore, that of each factor was obviously lower than FeatureSD. Conclusion Standard deviation of CT features among malignant foci within an individual was a powerful prognostic factor in vivo for lung cancer patients.

Supercomputer also known as gigantic computer, refers to a kind of computer with the best performance, the strongest function, the fastest operation speed and the largest storage capacity among all kinds of computers in an era. Supercomputer is a kind of complex electronic giant system, has huge numerical calculation ability and data processing ability, and can calculate large and complex tasks that ordinary personal computers and servers cannot complete. It has been used in high-end technology and cutting-edge scientific research at the beginning. With the continuous progress of science and technology, the upgrading speed of computer is very fast. Therefore, Supercomputer has distinct temper of times, and its evaluation standard is also dynamic. It is an important embodiment of scientific and technological strength of the country and plays a huge role in promoting national economic development, social progress and national defense construction. The paper reviews the development of the international supercomputer and overview of supercomputer development in China. It analyzes the current situation of supercomputer R&D, shows the supercomputer technology problem and innovation-storage access wall, communication wall, reliability wall, energy consumption wall. This paper also looks forward to the future of supercomputer, so as to provide some reference for scholars in related fields.

Background To compare glomerular filtration rate (GFR) among individuals, GFR is usually scaled to body surface area (BSA) based on the ratio method, which has been debated for its accuracy in recent years. Reference to the BSA as a normalization standard is the most common method currently in use but has limitations. This study was designed to a better variable to scale GFR. Methods We measured 99mTc- diethylene triamine pentaacetic acid plasma clearance (uncorrected GFR, uGFR) for 322 healthy adults who were enrolled according to the SENIEUR protocol. The individuals were randomly grouped into A and B for regressing and validating the optimal variable, respectively. Nonlinear regression was performed against uGFR, and the selected independent variables were body weight, height, age, and sex. Results Among several tested models, the regression coefficients of weight-age formula (W-A) were in narrower 95% confidence interval (CI). The coefficient of determination of the regression line between W-A and uGFR, as an indicator to explain the percentage of variations of GFR, was higher than that of other variables in both groups. The coefficient of determination of the regression line between W-A and uGFR was 0.571, which was higher than that of BSA (0.203) or TBW (0.241). Conclusion The index variable, based on both body weight and age, has a better statistical relationship to uGFR and is a better variable to scale GFR in adults.

Seymour R. Cray was an American engineer and supercomputer developer who designed a series of the fastest computers in the world in 1960-1980s. The difference between Cray and most other corporate engineers is that he often won those business battles. His success was attributable to his existence in a postwar culture where engineers were valued. He was able to also part of an extraordinary industry where revolutionary developments were encouraged, and even necessary. Lastly Cray is recognized as "the father of world supercomputer". From the perspective of science and technology history, this paper describes the history of Cray and his development of supercomputer. It also sums up his innovative ideas and scientific spirit. It provides a reference for supercomputer enthusiasts and peers in the history of computer research.

Supplemental Digital Content is available in the text, To explore whether weight-age (W-A) could be applied in clinical practice, this study was designed to verify the normalization ability of W-A by the data from another medical center, and to access the influence of the normalization on glomerular filtration rate (GFR) values in renal patients. Both plasma clearance (pGFR) and camera-based (gGFR), which were separately scaled to W-A and body surface area (BSA), were measured for patients with diffuse renal diseases. The patients (n = 298) were stratified according to the Chinese body mass index (BMI) criteria and were staged according to the Kidney Disease Outcome Quality Initiatives guideline based on gGFR and pGFR separately. The indices of intraclass correlation coefficient (ICC), concordance correlation coefficient (CCC), and ratio of residual standard deviation to pooled standard deviation (RSD/PSD) suggested that, for all patients and each BMI stratum, W-A was obviously better than BSA in scaling GFR. Both under pGFR or gGFR renal stages, only small amount of the patients encountered stage migrations from BSA to W-A scaled stages. The differences between any 2 of the unscaled, BSA scaled, and W-A scaled gGFR (or pGFR) were not obviously changed. Additionally, in some strata, W-A normalization is better than BSA normalization in decreasing the median bias between pGFR and gGFR. W-A is better than BSA in scaling GFR without obvious modifying GFR values and can be applied in routine clinical practice.

To evaluate the status of nuclear medicine in Beijing during 2005.For evaluating the status, a survey was performed in September 2006 by postal questionnaires. Forty-two nuclear medicine departments in Beijing were investigated regarding staff, equipment and clinical applications.Up to January 2007, thirty nuclear medicine departments had responded to our survey (response rate, 71.4%). These departments employed a total of 321 staff (141 physicians, 122 technicians, seven physicists, 22 nurses and 29 other staff) and were equipped with 47 scanners (42 SPECT, three PET, two PET/CT) before September 2006. During 2005, these departments completed 88 135 scans (84 734 SPECT, 3401 PET), 462 246 radioimmunoassays and 2228 radioisotope treatment (1288 Graves' disease, 268 thyroid cancer, 166 bone metastasis, 506 other). Furthermore, eight major hospitals hired more highly qualified staff with greater experience, such as professors or associate professors, and who had more clinical applications than did non-majors. The percentage of the departments that conducted daily and monthly quality control procedures was 43.3% and 40.0%, respectively.Nuclear medicine departments in Beijing are on a considerable scale, but still have a long way to go in order to be well developed. Hospitals in Beijing should increase the number of physicists and perform QA/QC procedures more frequently.

OBJECTIVE To survey nuclear medicine scans carried out in Beijing during 2005. METHODS Forty-two nuclear medicine departments were surveyed by using mailed questionnaires sent during September 2006. RESULTS By the end of January 2007, 30 out of 42 hospitals had replied to our survey. The estimated annual number of SPECT procedures was 6.72 per 1000 population during 2005. Among SPECT applications, whole-body bone scans (n=23,090) were performed with the highest frequency, followed by myocardial perfusion imaging (n=19,092), and renal function imaging (n=10,287). The estimated number of myocardial perfusion scintigraphy scans was 1530 procedures per million population. The annual number of PET procedures was 0.25 per 1000 population. Most of these PET and SPECT examinations used relative monotonous radiotracers and most patients were in the age group of 40-70 years. However, for each cancer and each type of application, age distributions slightly varied. In addition, the analysis of gender distribution revealed that the number of male patients was higher than for female patients. CONCLUSION The number of nuclear medicine scans carried out in Beijing during 2005 was considerable, with unbalanced clinical applications. Excluded myocardial perfusion scintigraphy, the frequencies of some applications were still lower than in western countries. Furthermore, most procedures used relatively monotonous radiotracers. Most patients were in the age group of 40-70 years and were male.

Using a best variable to scale glomerular filtration rate (GFR) is important for clinical practice. The variables, estimated by equations regressed from a healthy population, are usually used in scaling GFR of renal patients. However, because the predicted variables may deviate in renal patients, it is necessary to verify whether these variables can be used to reduce the variability of GFR of renal patients. This study was designed to use repeated measures analyses to identify the best variable for scaling GFR of renal patients.Patients with non-obstructive renal diseases were enrolled in this study. The absolute GFRs of (99m)Tc-DTPA renography (gGFR) and plasma clearance (pGFR) were measured. The indices relating to between-subjects variability, such as Passing and Bablok regression, intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC) were used to identify the best variable from body surface area (BSA), extracellular fluid volume (ECV), lean body mass (LBM), total body water (TBW), body mass index (BMI), and metabolic rate (MR).For the scaled indices related to between-subjects variability, ICC and CCC identified the same ranking sequence (BMILBMB(B; Boer)LBMJ(J; James)TBWECVB(B; Bird)ECVS(S; Silva)BSAMR). In the Passing and Bablok regression, the ratio of residual standard deviation to pooled standard deviation (RSD/PSD) produced the same ranking sequence as that identified by ICC and CCC.The estimated metabolic rate can explain most between-subjects variability of GFR, and seems to be the best variable for scaling GFR of renal patients.

In predicting pediatric kidney depth, we are especially interested in that the errors of most estimates are within a narrow range. Therefore, this study was intended to use the proportion of estimates within a range of −5 to 5 mm (P5 mm) to evaluate the formulas and tried to regress a kidney depth formula for children. The enrolled children aged from 1 to 19 years were randomly sampled into group A and group B (75% and 25% of all recruits, respectively). Using data of the group A, the test formula was regressed by nonlinear regression and subsequently Passing & Bablok regression, and validated in group B. The Raynaud, Gordon, Tonnesen, Taylor, and the test formulas were evaluated in the 2 groups. Accuracy was evaluated by bias, absolute bias, and P5 mm; and precision was evaluated by correlation coefficient. In addition, root-mean square error was used as a mixed index for both accuracy and precision. Body weight, height, and age did not have significant differences between the 2 groups. In the nonlinear regression, coefficients of the formula (kidney depth = a × weight/height + b × age) from group A were in narrower 95% confidence intervals. After the Passing & Bablok regression, biases of left and right kidney estimates were significantly decreased. In the evaluation of formulas, the test formula was obviously better than other formulas mentioned above, and P5 mm for left and right kidneys was about 60%. Among children younger than 10 years, P5 mm was even more than 70% for left and right kidney depths. To predict pediatric kidney depth, accuracy and precision of a step-by-step regressed formula were better than the 4 “standard” formulas.

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the United States. It is also well recognized that the incidence of CVD is substantially increased in postmenopausal women due to the loss of estrogen. Experimental and clinical data support vascular protective effects of estrogen by various mechanisms. However, administration of estrogen is also associated with an increased incidence of heart disease which limits its therapeutic potential. Given the demonstrated risks of conventional estrogen therapy, a search for novel, cost-effective, alternative vasoactive agents for prevention of CVD is of major importance in the effort to decrease the burden of CVD morbidity. Genistein, a major soy isoflavone, may be one of those alternative agents because of its selective affinity to estrogen receptor-beta and various beneficial effects on CVD. However, the mechanism of the cardioprotective effects of genistein is still unclear. The objectives of this study were (1) to investigate the effect of genistein on the expression of endothelial nitric oxide synthase (eNOS) both in vitro and in vivo; (2) to define the mechanism by which genistein regulates eNOS expression; and, (3) to examine whether genistein protects against tumor necrosis factor-alpha (TNF-α)-induced apoptosis in human aortic endothelial cells (HAECs). The results demonstrated that genistein, at physiologically achievable concentrations (1-10 μM) in individuals consuming soy products, enhanced the expression of eNOS protein and subsequently elevated nitric oxie (NO) synthesis in both HAECs and human umbilical vein endothelial cells, concomitant with the increased eNOS mRNA expression (2.6-fold of control) and eNOS promoter activity, suggesting that genistein activates eNOS transcription. Furthermore, dietary supplementation of genistein to spontaneously hypertensive rats restored aortic eNOS levels, improved aortic wall thickness, and alleviated hypertension, confirming the biological relevance of the in vitro findings. However, the effects of genistein on eNOS and NO were not mediated by activation of estrogen signaling, mitogen-activated protein kinase, phosphatidylinositol 3-kinase/Akt kinase, protein kinase C or inhibition of typrosine kinases, but possibly through activating the cAMP/protein kinase A/cAMP responsive elemant binding protein pathway. These data suggest that genistein has direct genomic effects on the vascular wall that are unrelated to its known actions, leading to increase in eNOS expression and NO synthesis, thereby improving vascular homeostasis. We also found that genistein (5-10 μM) significantly inhibited TNF-α-induced apoptosis in HAECs as determined by caspase-3 activation, apoptotic cell detection and DNA laddering. The anti-apoptotic effect of genistein was associated with an enhanced expression of anti-apoptotic Bcl-2 protein and its promoter activity that was ablated by TNF-α. Moreover, this anti-apoptotic effect of genistein was not mediated by extracellular signal-regulated kinase 1/2, protein kinase A, or estrogen receptor. However, inhibition of p38 mitogen-activated protein kinase (p38) by SB203580 completely abolished the cytoprotective effect of genistein, suggesting that genistein acted through the p38-dependent pathway. Accordingly, stimulation of HAECs with genistein resulted in rapid and dose-dependent activation of p38. Unlike TNF-α which specifically activated p38α, genistein selectively induced phosphorylation of p38β, suggesting that p38β, but not p38α, is essential for the cytoprotective effect of genistein. These findings provide the evidence that genistein acts as a survival factor for vascular ECs to protect cells against apoptosis via activation of p38β. Taken together, the resuls of the present study suggest that genistein can act directly on vascular ECs, improves endothelium homeostasis by promoting eNOS expression and endothelial-derived NO synthesis through activating the cAMP/PKA/CREB cascade, and protects against TNF-α-induced apoptosis via activation of p38 β. These data potentially provide a basic mechanism underlying the physiological effects of genistein in the vasculature. Ph. D.