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Obesity and prostate cancer-specific mortality after radical prostatectomy: results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database.
BackgroundAt the population level, obesity is associated with prostate cancer (PC) mortality. However, few studies analyzed the associations between obesity and long-term PC-specific outcomes after initial treatment.MethodsWe conducted a retrospective analysis of 4268 radical prostatectomy patients within the Shared Equal Access Regional Cancer Hospital (SEARCH) database. Cox models accounting for known risk factors were used to examine the associations between body mass index (BMI) and PC-specific mortality (PCSM; primary outcome). Secondary outcomes included biochemical recurrence (BCR) and castration-resistant PC (CRPC). BMI was used as a continuous and categorical variable (normal <25 kg/m2, overweight 25-29.9 kg/m2 and obese ⩾30 kg/m2). Median follow-up among all men who were alive at last follow-up was 6.8 years (interquartile range=3.5-11.0). During this time, 1384 men developed BCR, 117 developed CRPC and 84 died from PC. Hazard ratios were analyzed using competing-risks regression analysis accounting for non-PC death as a competing risk.ResultsOn crude analysis, higher BMI was not associated with risk of PCSM (P=0.112), BCR (0.259) and CRPC (P=0.277). However, when BMI was categorized, overweight (hazard ratio (HR) 1.99, P=0.034) and obesity (HR 1.97, P=0.048) were significantly associated with PCSM. Obesity and overweight were not associated with BCR or CRPC (all P⩾0.189). On multivariable analysis adjusting for both clinical and pathological features, results were little changed in that obesity (HR=2.05, P=0.039) and overweight (HR=1.88, P=0.061) were associated with higher risk of PCSM, but not with BCR or CRPC (all P⩾0.114) with the exception that the association for overweight was no longer statistical significant.ConclusionsOverweight and obesity were associated with increased risk of PCSM after radical prostatectomy. If validated in larger studies with longer follow-up, obesity may be established as a potentially modifiable risk factor for PCSM
The influence of yarn parameters on the ultraviolet protection of yarns
Improving ultraviolet (UV) protection of textiles is essential to protect wearers against UV radiation induced risks. In addition to fabric parameters, yarn parameters are important factors affecting UV protection of textiles. This work is to examine the influence of yarn parameters on UV protection in order to set up a statistical model for predicting the UV protection of yarns. Wool yarns with different variables were used to test the ultraviolet protection factor (UPF) values for data analysis and the model verification. The model provides the optimized parameters for the UV protective fabric design. This work is helpful as a pre-cursor to the development of a more advanced optical model, which will look at understanding the penetration of UV light through fibres, yarns and fabrics
Effects of exogenous spermidine on photosynthesis, xanthophyll cycle and endogenous polyamines in cucumber seedlings exposed to salinity
The effects of exogenous spermidine (Spd, 1 mmol·L-1) on photosynthetic characteristics, xanthophylls cycle components and endogenous polyamines levels were investigated in cucumber seedlings subjected to salt stress (75 mmol·L-1 NaCl). Chlorophyll contents and net photosynthetic rate (PN) of cucumber seedlings showed a significant decrease under salinity but an increase with exogenous Spd application. Salt stress caused a remarkable decline in the maximum quantum efficiency (Fv/Fm) and the actual efficiency of photosystem II (ФPSⅡ), where an increase was observed in the constitutive loss processes (ΦNO). Application of exogenous Spd significantly decreased ФNO and enhanced regulated non-photochemical energy loss (ФNPQ) in the salt-stressed plants. Spd treatment caused an increase in the size of xanthophyll cycle pool (VAZ) and further enhanced de-epoxidation of the xanthophyll cycle (DEPS) under salt stress. These results suggest that exogenous Spd alleviated salt-mediated decline in photosynthetic efficiency through the enhanced involvement of the energy dissipation that is dependent on the xanthophyll cycle. In addition, foliar spray Spd significantly increased the free, bound and conjugated polyamines in the leaves of the salt stressed plants. Spd also increased the free putrescine (Put)/(Spd+Spm) ratio and decreased bound and conjugated Put/(Spd+Spm) under salinity. Thus, we conclude that Spd can alleviate salt-induced damage on cucumber seedlings by regulating the levels of endogenous polyamines, which was associated with an improvement in the photochemical efficiency of PSII of the salt stressed plants.Key words: Cucumber, endogenous polyamines, photosynthetic characteristics, salt stress, spermidine
Persistence and Eventual Demise of Oxygen Molecules at Terapascal Pressures
Computational searches for structures of solid oxygen under high pressures in the multi-TPa range are carried out using density-functional-theory methods. We find that molecular oxygen persists to about 1.9 TPa at which it transforms into a semiconducting square-spiral-like polymeric structure (I41/acd) with a band gap of ∼3.0 eV. Solid oxygen forms a metallic zigzag chainlike structure (Cmcm) at about 3.0 TPa, but the chains in each layer gradually merge as the pressure is increased and a structure of Fmmm symmetry forms at about 9.3 TPa in which each atom has four nearest neighbors. The superconducting properties of molecular oxygen do not vary much with compression, although the structure becomes more symmetric. The electronic properties of oxygen have a complex evolution with pressure, swapping between insulating, semiconducting, and metallic
Dam inactivation in Neisseria meningitidis: prevalence among diverse hyperinvasive lineages
BACKGROUND: DNA adenine methyltransferase (Dam) activity is absent in many, but not all, disease isolates of Neisseria meningitidis, as a consequence of the insertion of a restriction endonuclease-encoding gene, the 'dam replacing gene' (drg) at the dam locus. Here, we report the results of a survey to assess the prevalence of drg in a globally representative panel of disease-associated meningococci. RESULTS: Of the known meningococcal hyper-invasive lineages investigated, drg was absent in all representatives of the ST-8 and ST-11 clonal complexes tested, but uniformly present in the representatives of the other hyper-invasive lineages present in the isolate collection (the ST-1, ST-4, ST-5, ST-32 and ST-41/44 clonal complexes). The patterns of sequence diversity observed in drg were consistent with acquisition of this gene from a source organism with a different G+C content, at some time prior to the emergence of present-day meningococcal clonal complexes, followed by spread through the meningococcal population by horizontal genetic exchange. During this spread a number of alleles have arisen by mutation and intragenic recombination. CONCLUSION: These findings are consistent with the idea that possession of the drg gene may contribute to the divergence observed among meningococcal clonal complexes, but does not have a direct mechanistic involvement in virulence
Coronal jets, magnetic topologies, and the production of interplanetary electron streams
We investigate the acceleration source of the impulsive solar energetic particle (SEP) events on 2007 January 24. Combining the in situ electron measurements and remote-sensing solar observations, as well as the calculated magnetic fields obtained from a potential-field source-surface model, we demonstrate that the jets associated with the hard X-ray flares and type-III radio bursts, rather than the slow and partial coronal mass ejections, are closely related to the production of interplanetary electron streams. The jets, originated from the well-connected active region (AR 10939) whose magnetic polarity structure favors the eruption, are observed to be forming in a coronal site, extending to a few solar radii, and having a good temporal correlation with the electron solar release. The open-field lines near the jet site are rooted in a negative polarity, along which energetic particles escape from the flaring AR to the near-Earth space, consistent with the in situ electron pitch angle distribution. The analysis enables us to propose a coronal magnetic topology relating the impulsive SEP events to their solar source
Catalytic Cracking and Heat Sink Capacity of Aviation Kerosene Under Supercritical Conditions
Catalytic cracking of China no. 3 aviation kerosene using a zeolite catalyst was investigated under supercritical conditions. A three-stage heating/cracking system was specially designed to be capable of heating 0.8 kg kerosene to a temperature of 1050 K and pressure of 7.0 MPa with maximum mass flow rate of 80 g/s. Sonic nozzles of different diameters were used to calibrate and monitor the mass flow rate of the cracked fuel mixture. With proper experiment arrangements, the mass flow rate per unit throat area of the cracked fuel mixture was found to well correlate with the extent of fuel conversion. The gaseous products obtained from fuel cracking under different conditions were also analyzed using gas chromatography. Composition analysis showed that the average molecular weight of the resulting gaseous products and the fuel mass conversion percentage were a strong function of the fuel temperature and were only slightly affected by the fuel pressure. The fuel conversion was also shown to depend on the fuel residence time in the reactor, as expected. Furthermore, the heat sink levels due to sensible heating and endothermic cracking were determined and compared at varying test conditions. It was found that at a fuel temperature of similar to 1050 K, the total heat sink reached similar to 3.4 MJ/kg, in which chemical heat sink accounted for similar to 1.5 MJ/kg
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