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Background: The tumor area may be a potential prognostic indicator. The present study aimed to determine and validate the prognostic value of tumor area in curable colon cancer. Methods: This retrospective study included a training and validation cohorts of patients who underwent radical surgery for colon cancer. Independent prognostic factors for overall survival (OS) and disease-free survival (DFS) were identified using Cox proportional hazards regression models. The prognostic discrimination was evaluated using the integrated area under the receiver operating characteristic curves (iAUCs) for prognostic factors and models. The prognostic discrimination between tumor area and other individual factors was compared, along with the prognostic discrimination between the tumor-node-metastasis (TNM) staging system and other prognostic models. Two-sample Wilcoxon tests were carried out to identify significant differences between the two iAUCs. A two-sided P < 0.05 was considered statistically significant. Results: A total of 3051 colon cancer patients were included in the training cohort and 872 patients in the validation cohort. Tumor area, age, differentiation, T stage, and N stage were independent prognostic factors for both OS and DFS in the training cohort. Tumor area had a better OS and DFS prognostic discrimination characteristics than T stage, maximal tumor diameter, differentiation, tumor location, and number of retrieved lymph nodes. The novel prognostic model of T stage + N stage + tumor area (iAUC for OS, 0.714, P < 0.001; iAUC for DFS, 0.694, P < 0.001) showed a better prognostic discrimination than the TNM staging system (T stage + N stage; iAUC for OS, 0.664; iAUC for DFS, 0.658). Similar results were observed in an independent validation cohort. Conclusions: Tumor area was identified as an independent prognostic factor for both OS and DFS in curable colon cancer patients, and in cases with an adequate number of retrieved lymph nodes. The novel prognostic model of combining T stage, N stage, and tumor area may be an alternative to the current TNM staging system. [ABSTRACT FROM AUTHOR]

To evaluate the biomass distribution of fishery resources for hydroacoustic data, acoustic measurement was combined with ordinary kriging (OK) to perform data processing, which was supported with trawling data. Acoustic data were collected during daytime by using a Simrad EY60 echosounder with 70- and 120-kHz split beam transducers. Afterward, the undesirable data were eliminated, data transformation was carried out, the semivariogram models were statistically compared and filtered and subsequently OK was performed. The goodness of fit of OK was also assessed with the determination coefficient (R2), mean error (ME), and root mean square error (RMSE). The exponential model was the most suitable semivariogram model for the data, and the goodness of fit of OK was good (R2 = 0.8986, Pearson's r = 0.9481). The distribution pattern of fishery resources is probably less distributed from north to south and from east to west, which is consistent with the findings in the Summer between 1998 and 1999. [ABSTRACT FROM AUTHOR]

In order to investigate the continuous reverse-flow oxidation of ultralow heating value coalbed methane, a two-dimensional mathematical mode for the continuous reverse-flow oxidation of ultralow heating value coalbed methane was set up. The software FLUENT was used to simulate the thermal structure of the oxidation bed and the effect of operating conditional parameters. The result indicates that: the temperature field of oxidation bed presents trapezium. There exists obvious difference in temperature at the both ends of oxidation bed, and it is helpful to preheat the fresh gas and recover the flue gas heat. Comparing with the conventional porous media combustion, the continuous reverse-flow oxidation has lower peak temperature and outlet temperature, and the methane conversion rate remains high. With the increase of methane concentration, the high-temperature zone widens, the both of temperature and outlet temperature rise, and the reaction area moves to inlet continuously. As the inlet velocity increases, the peak of temperature and outlet temperature both rises significantly, and the reaction area shifts toward to outlet continuously. With the increase of wall heat loss, the peak of temperature and the whole temperature of oxidation bed both reduce, the high-temperature zone becomes narrow obviously, and the reaction area is far away from the inlet. [ABSTRACT FROM AUTHOR]

BACKGROUND: Constipation is a common adverse effect of opioid use and has been associated with increased healthcare utilization and costs among patients receiving opioids for pain management. OBJECTIVE: To compare the healthcare utilization and costs of Medicaid patients with chronic non- cancer pain with and without constipation who were receiving opioids. METHODS: This retrospective, claims-based study was conducted using data from the Truven Health MarketScan Medicaid Multi-State database. Patients with no evidence of cancer who initiated opioid therapy between January 1, 2009, and June 30, 2013, were eligible for the study. Patients had to have continuous enrollment in the database in the 6 months before and 12 months after opioid initiation, with no evidence of substance abuse or functional or inflammatory bowel disease. Medical and pharmacy claims during the 12 months after opioid initiation were evaluated for a diagnosis of constipation or for prescription or over-the-counter medications indicative of constipation. All-cause healthcare utilization and costs were measured over the same period and were compared between propensity score-matched cohorts of patients with evidence of constipation and patients without constipation. RESULTS: Of the 25,744 patients meeting the study inclusion criteria, 2716 (10.5%) had evidence of constipation. After 1:1 propensity score matching, the 2 cohorts had similar demographic and clinical characteristics (ie, mean age, 47 years; 26%-27% male). During the 12-month follow-up period, healthcare utilization was more frequent among patients with constipation, including inpatient admissions and emergency department visits, than in the matched patients without constipation. The total all-cause mean healthcare costs were substantially higher among the patients with constipation ($28,234; 95% confidence interval [CI], $24,307-$32,160) than in the patients without constipation ($13,709; 95% CI, $12,618-$14,801), with a median cost difference of $4166 per patient (P <.001). CONCLUSION: Among Medicaid enrollees who receive opioids for chronic noncancer pain, constipation is associated with increased all-cause healthcare utilization and costs. [ABSTRACT FROM AUTHOR]

An AZ80 bar with the cross-section of 290 mm×230 mm was fabricated by “multi-direction forging (MDF) + extrusion + on-line water quenching”. The bar was cold compressed along 230 mm direction (ND) with a reduction of about 20 mm, which brought about numerous twins in the center (C) of the cross-section, while the outer (O) had few twins. The influences of deformation twinning on mechanical properties and precipitation reactions were studied. Results show that room-temperature (RT) tensile properties of C and O along extrusion direction (ED), 290 mm direction (TD) and ND exhibit remarkable anisotropy and heterogeneity. ED in O (ED-O) has the highest strength, i.e. R P0.2 , R m and A are 295 MPa, 401 MPa and 10%, respectively, while ND-C has the lowest strength, i.e. R P0.2 , R m and A are 164 MPa, 273 MPa and 7%, respectively. Such remarkable anisotropy and heterogeneity are mainly determined by texture, and deformation twinning has a major influence on texture. Before cold compression, two orientations exist in C, i.e. [0001] Mg //TD and [0001] Mg //ND; after cold compression, the texture of O is almost unchanged, however, that of C is largely transformed by deformation twins, that is, [0001] Mg //TD orientation is immensely weakened, while [0001] Mg ∼//ND is accordingly enhanced. After 155 °C/7 h aging, β particles continuously precipitate in deformation twins, and these twin-related β particles are much finer than discontinuous β lamellae. [ABSTRACT FROM AUTHOR]

The evolution rules of transitional phases β1′ and β2′ during single and double aging and the heterogeneous nucleation of β1′ rods on α-Mn particles in a Mg-6 wt%Zn-1wt%Mn (ZM61) alloy were studied by TEM technique. Age-hardening curves (130, 160, 180, 200 and 230 °C) show that double aging can more greatly enhance hardening level and rate than single aging. The rapid nucleation and the elongation of β1′ rods occupies the stage before peak aging; the volume fraction increase of β1′ rods results in hardness rise and also a huge accumulation of strain energy; in the over-aging stage the growth of β2′ discs at the cost of β1′ rods can effectively relieve such a strain energy accumulation. G. P. zones of about 10 nm in diameter are densely distributed in matrix after the pre-aging (90 °C/24 h), which can act as the heterogeneous nuclei for β1′ rods and thus considerably raise their number density. Moreover, β1′ rods frequently heterogeneously nucleate on α-Mn particles, because such heterogeneous nucleation can result in a coherent β1′/α-Mn interface and thus reduce the interfacial energy. [ABSTRACT FROM AUTHOR]

Wide-azimuth, long-offset surveys are becoming increasingly common in unconventional exploration plays where one of the key routine processes is maintaining data fidelity at far offsets. The conventional NMO correction that processes the data sample-by-sample results in the well-known decrease of frequency content and amplitude distortion through stretch, which lowers the seismic resolution and hinders Xp-pp and amplitude variation with offset and azimuth (AVAz) analysis of the long-offset signal. To mitigate the stretch typically associated with large offsets, we use a matching-pursuit-based normal moveout correction (MPNMO) to reduce NMO-stretch effects in long-offset data. MPNMO corrects the data wavelet-by-waveiet rather than sample-by-sample, thereby avoiding stretch. We apply our technique (1) to a set of synthetic gathers and (2) as part of a residual velocity analysis workflow to a prestack time-migrated data volume acquired over the Northern Chicontepec Basin, Mexico. Test results show that MPNMO can produce relatively nonstretched events and generate higher temporal resolution prestack gathers. [ABSTRACT FROM AUTHOR]

Spectral decomposition is a proven, powerful means of identifying strong amplitude anomalies at specific frequencies that are otherwise buried in the broadband response. Most publications focus on using spectral magnitude instead of phase components to identify lateral changes in stratigraphy, wavefield attenuation from the quality factor Q, and unconformities between geologic formations. Although seismic acquisition and processing preserve phase very well, little has been published about interpreting the phase components resulting from spectral decomposition. Morlet complex wavelet transform phase residues can improve seismic spectral decomposition interpretation by detecting the phase discontinuities in the joint time-frequency spectral phase component. Phase singularities can be associated with geologic features, and work with phase residues can improve interpretation of the Anadarko basin Red Fork channels of Oklahoma, U.S.A. [ABSTRACT FROM AUTHOR]

Effects of incubation time (5-150 days) and moisture (75% field capacity, wetting-drying cycle and flooding) on the redistribution of copper (Cu), lead (Pb), cadmium (Cd) and mercury (Hg) in a loessial soil of China were studied. The amounts of metals spiked were 100 mg.kg-1 for Cu and Pb, 2 mg.kg-1 for Cd and Hg, respectively. Metals in the incubated soil samples were fractionated termly from 5 to 150 days by the sequential extraction procedure, where the speciation of metals were experimentally defined as ex- changeable, carbonate-, Fe-Mn oxide-, organic matter- bound and residual fractions. The heavy metals spiked in the soil were time-dependently transferred from the easily ex- tractable fractions (the exchangeable and carbonate-bound fractions) into less labile fractions (Fe-Mn oxide- and the organic matter-bound fractions). No significant changes were found in the residual fractions during the whole incubation. The decreases of metals in exchangeable fraction during the incubation could be simulated by a diffusion equation, and the decrease rates were applied to reflect the trans- formation rates of metal speciation among varying moisture treatments. For Cu, Pb and Cd, the transformation rate generally followed the order: flooding > wetting-drying cycle > 75% field capacity. The soil under flooding treatment had higher metal reactivity for Cu, Pb and Cd, resulting in the more complete movement of these metals toward stable fractions. However, such phenomena for Hg were not observed. It seemed that moisture effect on Hg speciation was not as significant as on Cu, Pb and Cd. [ABSTRACT FROM AUTHOR]

Under part-load conditions, a Francis turbine often suffers from very severe low-frequency and large-amplitude pressure fluctuation, which is caused by the unsteady motion of vortices (known as "vortex ropes") in the draft tube. This paper first reports our numerical investigation of relevant complex flow phenomena in the entire draft tube, based on the Reynolds-averaged Navier-Stokes (RANS) equations. We then focus on the physical mechanisms underlying these complex and somewhat chaotic flow phenomena of the draft-tube flow under a part-load condition. The flow stability and robustness are our special concern, since they determine what kind of control methodology will be effective for eliminating or alleviating those adverse phenomena. Our main findings about the flow behavior in the three segments of the draft tube, i.e., the cone inlet, the elbow segment, and the outlet segment with three exits, are as follows. (1) In the cone segment, we reconfirmed a previous finding of our research group based on the turbine's whole-flow RANS computation that the harmful vortex rope is an inevitable consequence of the global instability of the swirling flow. We further identified that this instability is caused crucially by the reversed axial flow at the inlet of the draft tube. (2) In the elbow segment, we found a reversed flow continued from the inlet cone, which evolves to slow and chaotic motion. There is also a fast forward stream driven by a. localized favorable axial pressure gradient, which carries the whole mass flux downstream. The forward stream and reversed flow coexist side-by-side in the elbow, with a complex and unstable shear layer in between. (3) In the outlet segment with three exits, the forward stream always goes through a fixed exit, leaving the other two exits with a chaotic and low-speed fluid motion. Based on these findings, we propose a few control principles to suppress the reversed flow and to eliminate the harmful helical vortex ropes. Of the methods we tested numerically, a simple jet injection in the inlet is proven successful. [ABSTRACT FROM AUTHOR]