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Efficient and affordable synthesis of graphene at low temperatures remains a significant challenge that potentially limits the use of this material in real-life applications. We describe here a simple, efficient, highly controllable technique to synthesize graphene by sputtering carbon from a solid source with the assistance of inductively coupled plasma (ICP), followed by controllable low-temperature annealing at about 550 oC. Raman scattering and X-ray diffraction characterizations have revealed the formation of a few layer graphene of high quality, confirmed by a low (∼0.48) ID/IG ratio. Raman analysis of samples formed at various annealing temperatures has revealed an upper limit for annealing temperature of 585 oC, beyond which the formed graphene reversibly dissolves in the metal. The ICP-assisted process was innovatively employed to improve the quality of thus-fabricated graphene at low temperatures. The mechanism of graphene formation was attributed to the metal induced graphitization in combination with the carbon precipitation onto the catalyst surface.

Purpose After curative resection of gastric or gastroesophageal junction adenocarcinoma, Intergroup Trial 0116 (Phase III trial of postoperative adjuvant radiochemotherapy for high risk gastric and gastroesophageal junction adenocarcinoma: Demonstrated superior survival for patients who received postoperative chemoradiotherapy with bolus fluorouracil (FU) and leucovorin (LV) compared with surgery alone. CALGB 80101 (Alliance; Phase III Intergroup Trial of Adjuvant Chemoradiation After Resection of Gastric or Gastroesophageal Adenocarcinoma) assessed whether a postoperative chemoradiotherapy regimen that replaced FU plus LV with a potentially more active systemic therapy could further improve overall survival. Patients and Methods Between April 2002 and May 2009, 546 patients who had undergone a curative resection of stage IB through IV (M0) gastric or gastroesophageal junction adenocarcinoma were randomly assigned to receive either postoperative FU plus LV before and after combined FU and radiotherapy (FU plus LV arm) or postoperative epirubicin, cisplatin, and infusional FU (ECF) before and after combined FU and radiotherapy (ECF arm). Results With a median follow-up duration of 6.5 years, 5-year overall survival rates were 44% in the FU plus LV arm and 44% in the ECF arm ( Plogrank = .69; multivariable hazard ratio, 0.98; 95% CI, 0.78 to 1.24 comparing ECF with FU plus LV). Five-year disease-free survival rates were 39% in the FU plus LV arm and 37% in the ECF arm ( Plogrank = .94; multivariable hazard ratio, 0.96; 95% CI, 0.77 to 1.20). In post hoc analyses, the effect of treatment seemed to be similar across all examined patient subgroups. Conclusion After a curative resection of gastric or gastroesophageal junction adenocarcinoma, postoperative chemoradiotherapy using a multiagent regimen of ECF before and after radiotherapy does not improve survival compared with standard FU and LV before and after radiotherapy.

PurposeConventional staging methods are inadequate to identify patients with stage II colon cancer (CC) who are at high risk of recurrence after surgery with curative intent. ColDx is a gene expression, microarray-based assay shown to be independently prognostic for recurrence-free interval (RFI) and overall survival in CC. The objective of this study was to further validate ColDx using formalin-fixed, paraffin-embedded specimens collected as part of the Alliance phase III trial, C9581.Patients and methodsC9581 evaluated edrecolomab versus observation in patients with stage II CC and reported no survival benefit. Under an initial case-cohort sampling design, a randomly selected subcohort (RS) comprised 514 patients from 901 eligible patients with available tissue. Forty-nine additional patients with recurrence events were included in the analysis. Final analysis comprised 393 patients: 360 RS (58 events) and 33 non-RS events. Risk status was determined for each patient by ColDx. The Self-Prentice method was used to test the association between the resulting ColDx risk score and RFI adjusting for standard prognostic variables.ResultsFifty-five percent of patients (216 of 393) were classified as high risk. After adjustment for prognostic variables that included mismatch repair (MMR) deficiency, ColDx high-risk patients exhibited significantly worse RFI (multivariable hazard ratio, 2.13; 95% CI, 1.3 to 3.5; P < .01). Age and MMR status were marginally significant. RFI at 5 years for patients classified as high risk was 82% (95% CI, 79% to 85%), compared with 91% (95% CI, 89% to 93%) for patients classified as low risk.ConclusionColDx is associated with RFI in the C9581 subsample in the presence of other prognostic factors, including MMR deficiency. ColDx could be incorporated with the traditional clinical markers of risk to refine patient prognosis.

PurposeObservational studies have demonstrated increased colon cancer recurrence in states of relative hyperinsulinemia, including sedentary lifestyle, obesity, and increased dietary glycemic load. Greater coffee consumption has been associated with decreased risk of type 2 diabetes and increased insulin sensitivity. The effect of coffee on colon cancer recurrence and survival is unknown.Patients and methodsDuring and 6 months after adjuvant chemotherapy, 953 patients with stage III colon cancer prospectively reported dietary intake of caffeinated coffee, decaffeinated coffee, and nonherbal tea, as well as 128 other items. We examined the influence of coffee, nonherbal tea, and caffeine on cancer recurrence and mortality using Cox proportional hazards regression.ResultsPatients consuming 4 cups/d or more of total coffee experienced an adjusted hazard ratio (HR) for colon cancer recurrence or mortality of 0.58 (95% CI, 0.34 to 0.99), compared with never drinkers (Ptrend = .002). Patients consuming 4 cups/d or more of caffeinated coffee experienced significantly reduced cancer recurrence or mortality risk compared with abstainers (HR, 0.48; 95% CI, 0.25 to 0.91; Ptrend = .002), and increasing caffeine intake also conferred a significant reduction in cancer recurrence or mortality (HR, 0.66 across extreme quintiles; 95% CI, 0.47 to 0.93; Ptrend = .006). Nonherbal tea and decaffeinated coffee were not associated with patient outcome. The association of total coffee intake with improved outcomes seemed consistent across other predictors of cancer recurrence and mortality.ConclusionHigher coffee intake may be associated with significantly reduced cancer recurrence and death in patients with stage III colon cancer.

Liquid scintillator (LS) will be adopted as the detector material in JUNO (Jiangmen Underground Neutrino Observatory). The energy resolution requirement of JUNO is 3%, which has never previously been reached. To achieve this energy resolution, the light yield of liquid scintillator is an important factor. PPO (the fluor) and bis-MSB (the wavelength shifter) are the two main materials dissolved in LAB. To study the influence of these two materials on the transmission of scintillation photons in LS, 25 and 12 cm-long quartz vessels were used in a light yield experiment. LS samples with different concentration of PPO and bis-MSB were tested. At these lengths, the light yield growth is not obvious when the concentration of PPO is higher than 4 g/L. The influence from bis-MSB becomes insignificant when its concentration is higher than 8 mg/L. This result could provide some useful suggestions for the JUNO LS., Comment: 5 pages, 9 figures, submitted to CPC

The fluorescence quantum yield of bis-MSB, a widely used liquid scintillator wavelength shifter, was measured to study the photon absorption and re-emission processes in liquid scintillator. The re-emission process affects the photoelectron yield and distribution, especially in a large liquid scintillator detector, thus must be understood to optimize the liquid scintillator for good energy resolution and to precisely simulate the detector with Monte Carlo. In this study, solutions of different bis-MSB concentration were prepared for absorption and fluorescence emission measurements to cover a broad range of wavelengths. Harmane was used as a standard reference to obtain the absolution fluorescence quantum yield. For the first time we measured the fluorescence quantum yield of bis-MSB up to 430 nm as inputs required by Monte Carlo simulation, which is 0.926$\pm$0.053 at $\lambda_{\rm ex}$ = 350 nm., Comment: 7 pages, 6 figures

BackgroundThe impact of physical activity on survival outcomes in patients with recurrent colon cancer has not been studied. We tested the association between the level of postdiagnosis physical activity and survival outcomes of patients with recurrent colon cancer.Patients and methodsWe conducted a prospective observational study of 237 patients with stage III colon cancer who had recurrence of disease. Physical activity was measured approximately 6 months after the completion of therapy (14 months after surgical resection) but before detection of recurrent disease. The primary end point of the study was survival time after recurrence.ResultsThe hazard ratio comparing patients who reported at least 18 metabolic equivalent task (MET) hours per week of physical activity with those engaging in < 3 MET hours per week was 0.71 (95% confidence interval, 0.46-1.11). Increasing total MET hours of physical activity per week was associated with a borderline statistical significance trend for improved survival after recurrence (P = .052). The benefit of physical activity on survival was not significantly modified by sex, body mass index (BMI), number of positive lymph nodes, age, baseline performance status, adjuvant chemotherapy regimen, or recurrence-free survival period.ConclusionTo our knowledge, this is the first study investigating the association of physical activity with survival outcome of patients with recurrent colon cancer. Although the association exceeded our predefined P trend < .05 for statistical significance, these findings warrant further studies of physical activity in patients with recurrent colorectal cancer.

PurposeA greater understanding of the biology of tumor recurrence should improve adjuvant treatment decision making. We conducted a validation study of the 12-gene recurrence score (RS), a quantitative assay integrating stromal response and cell cycle gene expression, in tumor specimens from patients enrolled onto Cancer and Leukemia Group B (CALGB) 9581.Patients and methodsCALGB 9581 randomly assigned 1,713 patients with stage II colon cancer to treatment with edrecolomab or observation and found no survival difference. The analysis reported here included all patients with available tissue and recurrence (n = 162) and a random (approximately 1:3) selection of nonrecurring patients. RS was assessed in 690 formalin-fixed paraffin-embedded tumor samples with quantitative reverse transcriptase polymerase chain reaction by using prespecified genes and a previously validated algorithm. Association of RS and recurrence was analyzed by weighted Cox proportional hazards regression.ResultsContinuous RS was significantly associated with risk of recurrence (P = .013) as was mismatch repair (MMR) gene deficiency (P = .044). In multivariate analyses, RS was the strongest predictor of recurrence (P = .004), independent of T stage, MMR, number of nodes examined, grade, and lymphovascular invasion. In T3 MMR-intact (MMR-I) patients, prespecified low and high RS groups had average 5-year recurrence risks of 13% (95% CI, 10% to 16%) and 21% (95% CI, 16% to 26%), respectively.ConclusionThe 12-gene RS predicts recurrence in stage II colon cancer in CALGB 9581. This is consistent with the importance of stromal response and cell cycle gene expression in colon tumor recurrence. RS appears to be most discerning for patients with T3 MMR-I tumors, although markers such as grade and lymphovascular invasion did not add value in this subset of patients.

Objective. Postoperative fatigue syndrome (POFS) is a general and main complication after surgery. However, there is no stable and standardized animal model for POFS. The aim of the present study was to establish a rodent model of POFS by small intestinal resection, with POFS evaluated by acknowledged physical and behavioral methods. Material and Methods. Forty-two Sprague-Dawley rats were randomly divided into four groups according to the length of a "middle" small intestinal resection: 0% (sham group; i.e., laparotomy alone), 10%, 40% and 70% groups, with corresponding lengths of small intestinal resections. Following surgery, the general state of health was evaluated. Tail suspension test, open field test and Morris water maze test were used to evaluate the degree of POFS. Serum albumin, transferrin, prealbumin and fibronectin were measured to assess the nutritional status, and superoxide dismutase (SOD) and malondialdehyde (MDA) were also measured. Results. As compared with the other three groups, the 70% small intestinal resection group showed the worst general state of health, decreased strength of the tail suspension test and decreased score of Morris water maze test (p < 0.05) after operation. All rats in whom the small intestinal resection was done demonstrated a certain degree of malnutrition and behavior of depression, and the 70% resection group had the lowest levels of transferrin, prealbumin and fibronectin as compared with the other groups (p < 0.05), as well as decreased SOD and increased MDA in serum (p < 0.05). Conclusions. Resection of 70% of the small intestine resulted in typical characteristics of POFS. As this procedure is simple, stable and easily reproducible, it may serve as a model for research on POFS.