128 research outputs found

    Effect of preoperative delay on prognosis for patients with early stage non-small cell lung cancer

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    AbstractObjective: Screening for lung cancer will discover many nodules of indeterminate pathology. Observation has the theoretic risk of permitting dissemination of a localized cancer and worsening prognosis, whereas immediate evaluation of benign conditions generates morbidity and cost. This study was conducted to assess the effect of delay in surgical intervention on survival for patients with early stage non-small cell lung cancer. Methods: Records for patients with resected pathologic stage I and II non-small cell lung cancer (1989-1999) were abstracted for patient age, race, sex, medical history, date of presentation, date and type of surgical treatment, pathologic stage, and date of death or last follow-up. Kaplan-Meier survival analysis was performed to test for the effect of delay (time from presentation to surgical intervention) on survival. Results: Eighty-four patients were identified. Median age was 66 years, median preoperative interval was 82 days (range, 1-641 days), and median follow-up was 3.3 years (range, 5 days-11.9 years). Median survival was 3.7 years. Overall 5-year survival was 40%; disease-specific 5-year survival was 63%. Log-rank analysis of the effect of delay on overall survival generated a P value of.54, with an estimated hazard ratio for a 90-day delay of 1.06 (95% confidence interval, 0.87-1.30). Conclusions: For this population, we were unable to detect a significant effect of delay on prognosis. Although these results suggest that the risk of judicious observation of indeterminate pulmonary nodules might be low, the 95% confidence interval is broad. Larger sample sizes are needed to reach definitive conclusions.J Thorac Cardiovasc Surg 2003;125:108-1

    Reputation as Public Policy for Internet Security: A Field Study

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    Cybersecurity is a national priority in this big data era. Because of the lack of incentives and the existence of negative externality, companies often underinvest in addressing security risks and accidents, despite government and industry recommendations. In the present article, we propose a method that utilizes reputation through information disclosure to motivate companies to behave pro-socially, improving their Internet security. Using outbound spam as a proxy for Internet security, we conducted a quasi-experimental field study for eight countries through SpamRankings.net. This outgoing-spam-based study shows that information disclosure on outgoing spam can help reduce outgoing spam, approximately by 16 percent. This finding suggests that information disclosure can be leveraged to encourage companies to reduce security threats. It also provides support for public policies that require mandatory reporting from organizations and offers implications for evaluating and executing such policies

    Bioconversion of Pelletized Big Bluestem, Switchgrass, and Low-Diversity Grass Mixtures Into Sugars and Bioethanol

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    Three crops of warm-season grasses are being developed for biomass production on northern rain-fed marginal farmland: big bluestem (BBS), switchgrass (SG), and a low diversity mixture of grasses (LDM). In this study, biomass harvested from established fields were compared for pelletization and subsequent conversion to sugars and ethanol. Each biomass was successfully pelletized to similar bulk densities without adding a binder at a commercial feed operation. Pelletizing increased the bulk density by 407% on average and was equally effective on all three biomass samples (528–554 kg/m3). Chemical analysis of the samples indicated that glucan and xylan contents were slightly reduced during pelletizing (by 23 and 16 g/kg, respectively), as well as theoretical ethanol yields, which are based upon total carbohydrate contents. Pellets and milled straws were pre-treated with either liquid hot-water or low-moisture ammonium hydroxide (LMA) and subsequently hydrolyzed with cellulases. Glucose and total sugar yields were similar for non-pellets and pellets using either pre-treatment; carbohydrates present in pellets were more efficiently recovered compared to non-pellets. LMA pretreated samples were separately hydrolyzed and fermented to ethanol using Scheffersomyces stipitis yeast. Hydrolysis recovered 69.7–76.8% of the glucose and 66.5–73.3% of the xylose across all samples. Glucose yields were 251–279 g/kg, db and were significantly lower for SG as compared to the other biomass samples. Recovered sugars were fermented to ethanol at 77.7–86.7% of theoretical yield. Final ethanol yields (245.9–275.5 L/Mg, db) were similar for all of the grasses and estimated to equate to production levels for BBS, LDM, and SG of 1,952, 2,586, and 2,636 l of ethanol per ha, respectively

    Bioconversion of Pelletized Big Bluestem, Switchgrass, and Low-Diversity Grass Mixtures Into Sugars and Bioethanol

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    Three crops of warm-season grasses are being developed for biomass production on northern rain-fed marginal farmland: big bluestem (BBS), switchgrass (SG), and a low diversity mixture of grasses (LDM). In this study, biomass harvested from established fields were compared for pelletization and subsequent conversion to sugars and ethanol. Each biomass was successfully pelletized to similar bulk densities without adding a binder at a commercial feed operation. Pelletizing increased the bulk density by 407% on average and was equally effective on all three biomass samples (528–554 kg/m3). Chemical analysis of the samples indicated that glucan and xylan contents were slightly reduced during pelletizing (by 23 and 16 g/kg, respectively), as well as theoretical ethanol yields, which are based upon total carbohydrate contents. Pellets and milled straws were pre-treated with either liquid hot-water or low-moisture ammonium hydroxide (LMA) and subsequently hydrolyzed with cellulases. Glucose and total sugar yields were similar for non-pellets and pellets using either pre-treatment; carbohydrates present in pellets were more efficiently recovered compared to non-pellets. LMA pretreated samples were separately hydrolyzed and fermented to ethanol using Scheffersomyces stipitis yeast. Hydrolysis recovered 69.7–76.8% of the glucose and 66.5–73.3% of the xylose across all samples. Glucose yields were 251–279 g/kg, db and were significantly lower for SG as compared to the other biomass samples. Recovered sugars were fermented to ethanol at 77.7–86.7% of theoretical yield. Final ethanol yields (245.9–275.5 L/Mg, db) were similar for all of the grasses and estimated to equate to production levels for BBS, LDM, and SG of 1,952, 2,586, and 2,636 l of ethanol per ha, respectively

    Simulation of metallic nanostructures for emission of THz radiation using the lateral photo-Dember effect

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    A 2D simulation for the lateral photo-Dember effect is used to calculate the THz emission of metallic nanostructures due to ultrafast diffusion of carriers in order to realize a series of THz emitters.Comment: Corrected version of a paper given at 2011 36th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz

    First-order phase transition vs. spin-state quantum-critical scenarios in strain-tuned epitaxial cobaltite thin films

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    Pr-containing perovskite cobaltites exhibit unusual valence transitions, coupled to coincident structural, spin-state, and metal-insulator transitions. Heteroepitaxial strain was recently used to control these phenomena in the model (Pr1βˆ’y_{1-y}Yy_y)1βˆ’x_{1-x}Cax_xCoO3βˆ’Ξ΄_{3-\delta} system, stabilizing a nonmagnetic insulating phase under compression (with a room-temperature valence/spin-state/metal-insulator transition) and a ferromagnetic metallic phase under tension, thus exposing a potential spin-state quantum critical point. The latter has been proposed in cobaltites and can be probed in this system as a function of a disorder-free variable (strain). We study this here via thickness-dependent strain relaxation in compressive SrLaAlO4_4(001)/(Pr0.85_{0.85}Y0.15_{0.15})0.70_{0.70}Ca0.30_{0.30}CoO3βˆ’Ξ΄_{3-\delta} epitaxial thin films to quasi-continuously probe structural, electronic, and magnetic behaviors across the nonmagnetic-insulator/ferromagnetic-metal boundary. High-resolution X-ray diffraction, electronic transport, magnetometry, polarized neutron reflectometry, and temperature-dependent magnetic force microscopy provide a detailed picture, including abundant evidence of temperature- and strain-dependent phase coexistence. This indicates a first-order phase transition as opposed to spin-state quantum-critical behavior, which we discuss theoretically via a phenomenological Landau model for coupled spin-state and magnetic phase transitions.Comment: main text + supplementary materia

    Bioconversion of Pelletized Big Bluestem, Switchgrass, and Low-Diversity Grass Mixtures Into Sugars and Bioethanol

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    Three crops of warm-season grasses are being developed for biomass production on northern rain-fed marginal farmland: big bluestem (BBS), switchgrass (SG), and a low diversity mixture of grasses (LDM). In this study, biomass harvested from established fields were compared for pelletization and subsequent conversion to sugars and ethanol. Each biomass was successfully pelletized to similar bulk densities without adding a binder at a commercial feed operation. Pelletizing increased the bulk density by 407% on average and was equally effective on all three biomass samples (528–554 kg/m3). Chemical analysis of the samples indicated that glucan and xylan contents were slightly reduced during pelletizing (by 23 and 16 g/kg, respectively), as well as theoretical ethanol yields, which are based upon total carbohydrate contents. Pellets and milled straws were pre-treated with either liquid hot-water or low-moisture ammonium hydroxide (LMA) and subsequently hydrolyzed with cellulases. Glucose and total sugar yields were similar for non-pellets and pellets using either pre-treatment; carbohydrates present in pellets were more efficiently recovered compared to non-pellets. LMA pretreated samples were separately hydrolyzed and fermented to ethanol using Scheffersomyces stipitis yeast. Hydrolysis recovered 69.7–76.8% of the glucose and 66.5–73.3% of the xylose across all samples. Glucose yields were 251–279 g/kg, db and were significantly lower for SG as compared to the other biomass samples. Recovered sugars were fermented to ethanol at 77.7–86.7% of theoretical yield. Final ethanol yields (245.9–275.5 L/Mg, db) were similar for all of the grasses and estimated to equate to production levels for BBS, LDM, and SG of 1,952, 2,586, and 2,636 l of ethanol per ha, respectively

    Do diagnostic delays in cancer matter?

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    background: The United Kingdom has poorer cancer outcomes than many other countries due partly to delays in diagnosing symptomatic cancer, leading to more advanced stage at diagnosis. Delays can occur at the level of patients, primary care, systems and secondary care. There is considerable potential for interventions to minimise delays and lead to earlier-stage diagnosis. methods: Scoping review of the published studies, with a focus on methodological issues. results: Trial data in this area are lacking and observational studies often show no association or negative ones. This review offers methodological explanations for these counter-intuitive findings. conclusion: While diagnostic delays do matter, their importance is uncertain and must be determined through more sophisticated methods
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