安第斯大学

Consider the following truncated Freud linear functional uz depending on a parameter z,〈uz,p〉=∫0∞p(x)e−zx4dx,z>0.The aim of this work is to analyze the properties of the sequence of orthogonal polynomials (Pn)n ≥ 0 with respect to uz. Such a linear functional is semiclassical and, as a consequence, we get the system of nonlinear difference equations (Laguerre-Freud equations) that the coefficients of the three-term recurrence satisfy. The asymptotic behavior of such coefficients is given. On the other hand, the raising and lowering operators associated with such a linear functional are obtained, and thus a second-order linear differential equation of holonomic type that (Pn)n ≥ 0 satisfies is deduced. From this fact, an electrostatic interpretation of their zeros is given. Finally, some illustrative numerical tests concerning the behavior of the least and greatest zeros of these polynomials are presented.

The sound horizon scale rs is a key source of information for measurements of H0 from early-time data, and is therefore a common target of new physics proposed to solve the Hubble tension. We present a sub-2% measurement of the Hubble constant that is independent of this scale, using data from the first data release of the Dark Energy Spectroscopic Instrument (DESI DR1). Building on previous work, we remove dependency on the sound horizon size using a heuristic rescaling procedure at the power spectrum level. A key innovation is the inclusion of uncalibrated (agnostic to rs) post-reconstruction BAO measurements from DESI DR1, as well as using the CMB acoustic scale theta & lowast; as a high-redshift anchor. Uncalibrated type-Ia supernovae are often included as an independent source of ohm m information; here we demonstrate the robustness of our results by additionally considering two supernova-independent alternative datasets. We find somewhat higher values of H0 relative to our previous work: 69.2+1.3-1.4, 70.3+1.4-1.2, and 69.6+1.3-1.8 km s-1 Mpc-1 respectively when including measurements from i) Planck/ACT CMB lensing & times; unWISE galaxies, ii) the DES Year 3 6 & times;2pt analysis, and iii) Planck/ACT CMB lensing + the DES Year 5 supernova analysis. These remarkably consistent constraints achieve better than 2% precision; they are among the most stringent sound horizon-independent measurements from LSS to date, and provide a powerful avenue for probing the origin of the Hubble tension.

Variability in construction activity execution times presents important challenges for planning reliability, particularly in industrialized construction contexts. Key factors contributing to high variability include inadequate coordination of disciplines, poor workflow optimization and uncollaborative work environments. This study uses a case study analysis to examine the impact of building information modelling (BIM) on reducing execution time variability, with a focus on planning reliability. A mixed-methods approach integrates qualitative data from expert interviews with quantitative insights derived from Monte Carlo and Latin Hypercube simulations, applied to real-world project data. Results show that BIM implementation reduces variability across key project activities where planning reliability indicators are often low, such as structural work and finishings. These findings demonstrate BIM's potential to enhance project performance and continuous improvement in industrialized construction, supporting strategies to increase planning reliability through better management of variability.

Post-harvest agricultural residues in Latin America are commonly underutilized, leading to greenhouse gas emissions and lost opportunities for bio-based value creation. This study tests the hypothesis that decentralized, farmer-scale pyrolysis technologies can deliver comparable agronomic benefits while exhibiting distinct techno-economic and climate performance under field conditions. Two biochar production technologies, top-lit up-draft (TLUD) and Kon-Tiki kilns were evaluated using corn cob residues as soil-amending bioproducts at a 1%(w/w) application rate. Both biochars were non-phytotoxic, exhibiting radish germination rates above 90% and no inhibition of radicle elongation. The TLUD biochar developed 21% higher microporosity than Kon-Tiki, indicating enhanced surface functionality for soil-plant interactions. Field application significantly improved soil properties relative to the control, increasing pH by 1.9 units, electrical conductivity by 1.8-fold, organic matter by 1.3-fold, and cation exchange capacity by 1.6-fold. These changes resulted in higher plant nutrient uptake, with foliar potassium and phosphorus concentrations increasing by 1.3- and 1.7-fold, respectively. The TLUD-derived biochar consistently outperformed Kon-Tiki in nutrient delivery, consistent with its higher surface area and fixed-carbon content. Integrating agronomic outcomes with net CO(2)e-based techno-economic performance reveals trade-offs between biochar quality, nutrient delivery, capital requirements, and climate benefits that cannot be inferred from laboratory-scale experiments. Techno-economic analysis showed that both technologies generate positive net CO(2)e benefits in situ, with TLUD requiring lower initial investment (>900 & euro; less than Kon-Tiki), while both systems converge in profitability after the first production cycle. These findings demonstrate that integrated field-scale assessment is essential to identify decentralized biochar systems that are agronomically effective, economically viable, and climate relevant.

BackgroundHead and neck cancer (HNC) represents a global health issue with significant physical, psychological, and social implications for patients. Netnography, an online research method, offers a unique opportunity to explore the experiences of HNC survivors in the digital age. This study analyzes the Instagram posts of HNC survivors to understand their lived experiences, coping mechanisms, and support networks.Materials and MethodsA netnographic content analysis was conducted on Instagram posts from 29 HNC survivor users. A mixed qualitative and quantitative approach was used to identify and interpret patterns and meanings within the textual data.ResultsThe analysis revealed 11 key themes. These individuals used their platforms to educate about HNC, sharing personal experiences to raise awareness of early detection and support newly diagnosed patients. They documented the multifaceted impact of treatment, including physical and emotional challenges such as pain, disfigurement, and loss of voice. Despite these difficulties, they emphasized the importance of social support networks, including family, friends, and healthcare providers, in their recovery process. Their posts expressed a range of emotions, from fear and anxiety to resilience and hope, reflecting the emotional struggle inherent in survivorship. They also shared experiences adapting to post-treatment life, including the use of medical devices, managing physical limitations, and economic difficulties. They celebrated small victories and offered practical advice and emotional support to others.ConclusionHNC survivors use social media to share their experiences, provide support, and advocate for themselves and others. Their stories highlight the multifaceted challenges of cancer and the importance of resilience, social support, and adaptation in the recovery process. These findings underscore the potential of netnography to provide valuable insights into the lived experiences of HNC survivors, which can inform healthcare practices and support programs.