University of La Rioja

Once we have seen the influence of convexity on the speed of convergence of the Newton method in Chap. 2, we now give three acceleration procedures for the Newton method, which are based on the influence of convexity and lead us to the three well-known third-order iterative methods of Chebyshev, Super-Halley, and Halley. Next, we study these three methods in the scalar case and in Banach spaces. In the scalar case, we see the influence that convexity has on each of the three methods, and from this, we guarantee that we can always solve a scalar equation by any of the three methods under certain restrictions on the degree of logarithmic convexity of the function involved in the equation to be solved. The study of these three methods in Banach spaces is carried out from the same point of view: the method of majoring sequences developed by Ortega for the Newton method, which simplifies the seminal majorant principle developed by Kantorovich to analyze the semilocal convergence of the Newton method in Banach spaces. We illustrate all theoretical results with examples, and, as in Chap. 2 for the Newton method, we use the theoretical significance of the methods to draw conclusions about the existence of solution of the equation to be solved.

To obtain a characterization of Newton-like iterative methods with order of convergence at least three, we extend to Banach spaces the result given by Gander for scalar equations and mentioned in Chap. 3. Many well-known third-order iterative methods are special cases of Gander’s result: the Chebyshev method, the Super-Halley method, the Halley method, Chebyshev-like methods, the Ostrowski method, the Exponential method, the Logarithmic method, and the Euler method. From the last methods, we see that we can generalize them to obtain a family of iterative methods that includes them. In addition, we see that all methods with R-order of convergence at least three in Banach spaces also admit a general expression. Our aim is to obtain a theory, the most general possible, relative to these iterative methods in Banach spaces which analyze their semilocal convergence under Kantorovich-type conditions for iterative methods with R-order of convergence at least three. For this, we use a technique based on recurrence relations. We then relax the last required conditions and, using the method of majorizing sequences, prove the semilocal convergence of the family of iterative methods defined previously. Finally, we analyze the semilocal convergence of a particular family of iterative methods, which is included in the previous family, whose R-order of convergence is at least four when applied to solve quadratic equations. We also use the theoretical significance of the methods to draw conclusions about the existence and uniqueness of solution of the equation to solve and illustrate all the theoretical results with examples.

The study of the concavity and convexity of a scalar function is an old problem studied by the mathematicians. It is perfectly known when a function is concave or convex. However, it is not so developed how to measure this concavity or convexity. If we think of a pointwise measure of convexity, as the curvature of a scalar function, the application of a concave scalar function to a convex scalar function reduces the convexity of the latter. Thus, taking into account that the logarithm is a concave scalar function, by a successive application of the logarithm to a convex scalar function at a point, we can measure the resistance that the function has to stop being convex at the point. That is, the number of times that the logarithm must be applied to the scalar function, so that it stops being convex at the point and becomes concave at it, and gives an index of pointwise measurement of the convexity of the function at the point. The degree of logarithmic convexity is defined in this way. We begin by introducing the concept of logarithmically convex function, which is a pointwise measure of the convexity of a scalar function, and by defining a few different types of convexity of the function at a point. We then extend the above concept and define an index of pointwise measurement of the convexity that we call degree of logarithmic convexity.

The main problem in the one-point iterative methods with R-order of convergence at least three is the evaluation of the second derivative of the operator involved. Moreover, the convergence conditions required to prove the semilocal convergence of these methods are usually more restrictive than those required to Newton-like methods. In this chapter, we try to solve both problems. Thus, from the Chebyshev method, we construct families of iterative methods where the second derivative of the operator involved does not appear in the algorithms, but with the same R-order of convergence as the Chebyshev method, so that the operational cost of the new methods is lower than that of the Chebyshev method. We construct four modifications of the Chebyshev method that improve this method in some sense, and all of them are free of second derivatives. All studies are done in Banach spaces and using the technique based on recurrence relations described in Chap. 4. Finally, the established theoretical results are illustrated with applications related to nonlinear Fredholm integral equations.

From the geometric interpretation of the Newton method in the scalar case, we see that the method runs faster the lower the convexity of the function involved in the equation to be solved. To measure the convexity of the function, we can use the degree of logarithmic convexity defined in Chap. 1, which, as we have seen, is a point measure of convexity. We begin the chapter by studying the convergence of the Newton method on the real line and continue looking at the influence that the convexity of the function involved has on the speed of convergence of the method. Next, we do two analyses of the convergence of the method in Banach spaces. For this, we first extend the degree of logarithmic convexity to Banach spaces, and although the geometric sense that it has in the scalar case is lost, we analyze its existence based on the classical Kantorovich conditions. In the first study, the convergence of the method is analyzed based on the type of conditions required to the degree of logarithmic convexity, emphasizing the majorant principle introduced by Kantorovich to study the semilocal convergence of the Newton method, the fixed point techniques for the study of the global convergence, which guarantee the extension of the domain of starting points, together with the use of auxiliary points, and the ideas contributed by Dennis and Schnabel to obtain the local convergence of the method. In the second study, we use the degree of logarithmic convexity under Kantorovich-type conditions. In semilocal convergence studies, we use the theoretical significance of the method to draw conclusions about the existence and uniqueness of solution in some cases, as well as to give a priori error estimates based on the Ostrowski technique.

A series of Pt(II) complexes [Pt(piq)(-NS)]2 (piq = 1-phenylisoquinolinate) [NS = Spy (pyridine-2-thiolate), Spy-CF3 (5-trifluoromethylpyridine-2-thiolate), S-Q (quinoline-2-thiolate) and Spy-N (pyrimidine-2-thiolate)] are presented. They display a “half-lantern” disposition with two “Pt(piq)” fragments connected by a double pyridine thiolate bridge and remarkable short Pt-Pt distances (2.8-2.9 A). The strong bonding interaction between the Pt(II) centers endows them with bright (up to 15% Quantum Yield (QY)) deep-red (down to 740 nm) phosphorescence in both powder and PMMA coatings. Theoretical calculations based on time-dependent density functional theory (TD-DFT) point out that the nature of the emitting exciting state is related to a 3MMLCT [ds*(Pt-Pt)-pi*(piq)] transition. However, the emission shifts noticeably towards the NIR region (up to 850 nm) in solution, depending on the type of complex and the concentration. Besides, a dual emission was noted related to a high-energy 3MLCT [d(Pt)-pi*(piq)] structured emission feature and the low-energy and broad 3MMLCT emission band, highlighting the versatility of the half-lantern structure. Given their photophysical properties, the complexes were applied as color down-converting filters for the fabrication of deep-red hybrid light-emitting diodes (HLEDs), achieving external quantum efficiencies of ca. 1 %.

Objective: Social support is understood as a protective factor for mental health and emotional well-being, especially at school. The Multidimensional Scale of Perceived Social Support (MSPSS) is one of the most widely used tools worldwide to assess this construct. The main purpose of the present study was to validate the scores of the MSPSS in a large sample of non-clinical adolescents. Method: The sample consisted of 2,235 compulsory secondary education students in Spain ( Mage = 14.49, SDage = 1.76, age range 12-18 years, 52% female) obtained by stratified random sampling. Results: The model, consisting of three interrelated factors, showed the most adequate goodness-of-fit indices. The results support the measurement invariance of the MSPSS across sex, age, and sexual orientation. McDonald’s omega reliability indices between .862-.934 were obtained. MSPSS scores were significantly and negatively associated with emotional and behavioral problems, depression, and suicidal behavior, and positively associated with life satisfaction. Conclusions: The MSPSS is a reliable instrument to assess social support through self-report in school settings. In this regard, assessing social support using this tool is particularly useful in programs promoting well-being or preventing mental health disorders

Background Fruit set is the transformation of flower ovaries into berries. Fruit set rate determines the number of berries produced per bunch, which is a major component of yield in grapevines. Malbec is a black-berried grapevine cultivar recognized for producing high-quality wines, and particularly relevant for Argentina’s winemaking industry. Clonal variation has been reported for Malbec at the phenotypic and molecular levels. However, less is known about clonal variation for agronomically relevant features affecting yield. In this work we evaluated 25 Malbec clones for the fruit set rate and other related features over multiple seasons. Results The mean fruit set rate was 38.6% (ranged between 13.1% and 65.8%) in 2021/22, and 32.1% (ranged between 9.8% and 50%) in 2022/23 season, evidencing a wide range of within-season variation. Besides the expectable interannual differences, significant and positive correlations were found over seasons for the fruit set rate, number of flowers per inflorescence and number of berries per bunch. Moreover, multivariate clustering analyses consistently grouped the evaluated clones into three distinct groups. Two of these groups showed similar number of flowers per inflorescence, but significantly different fruit set rates and number of berries per bunch. Representative clones of the latter two groups were in-depth analyzed in 2023/24, supporting previous seasons results and revealing differences in their floral phenotypes. Conclusions We found a wide range of clone-dependent variation for the evaluated traits, which generated great differences in the reproductive performance and yield within Malbec. We hypothesized that the observed differences were associated to somatic mutations, affecting the correct development and functionality of flower organs in a clone-specific way.

Infestation by Varroa destructor is responsible for high mortality rates in Apis mellifera colonies worldwide. This study was designed to develop and test under field conditions a new free software (VarroDetector) based on a deep learning approach for the automated detection and counting of Varroa mites using smartphone images of sticky boards collected in honeybee colonies. A total of 204 sheets were collected, divided into four frames using green strings, and photographed under controlled lighting conditions with different smartphone models at a minimum resolution of 48 megapixels. The Varroa detection algorithm comprises two main steps: First, the region of interest where Varroa mites must be counted is established. From there, a one-stage detector is used, namely YOLO v11 Nano. A final verification was conducted counting the number of Varroa mites present on new sticky sheets both manually through visual inspection and using the VarroDetector software and comparing these measurements with the actual number of mites present on the sheet (control). The results obtained with the VarroDetector software were highly correlated with the control (R² = 0.98 to 0.99, depending on the smartphone camera used), even when using a smartphone for which the software was not previously trained. When Varroa mite numbers were higher than 50 per sheet, the results of VarroDetector were more reliable than those obtained with visual inspection performed by trained operators, while the processing time was significantly reduced. It is concluded that the VarroDetector software Version 1.0 (v. 1.0) is a reliable and efficient tool for the automated detection and counting of Varroa mites present on sticky boards collected in honeybee colonies.

Background The admission of a family member to intensive care represents an emotionally complex experience, often characterised by anxiety, stress and uncertainty. ICU diaries, compiled by nurses and family members, have been proposed as a useful tool to support caregivers’ psychological well-being, improve communication and humanise the care environment. The aim of the study was to describe the content of ICU diaries filled out by family members to explore the experiences and meanings attributed to the diaries. Methods The study used a qualitative approach based on thematic analysis of diaries completed by 16 family members of patients admitted to intensive care units. The data were coded and analysed to identify recurrent themes and to understand the emotional and psychological experience of the family members. Results Three main themes emerged from the analysis: time, the family context (including maintaining contact with the patient, the relatives‘emotions, fear of suffering, spirituality, the person at the centre of the relatives’ lives and connection with the outside world) and the usefulness of the diary in understanding the care process. The diaries facilitated the continuity of the affective bond with the patient, offered a space to express emotions and improved communication with healthcare professionals. Conclusion The results highlight the value of ICU diaries in supporting family members during the patient’s admission, reducing stress and strengthening the relationship with the healthcare team. The practical implications suggest the importance of promoting the structured use of diaries to foster more empathetic and family-centred care. Clinical trial number Not applicable.

Tequila, one of Mexico's most emblematic products, has seen a steady growth in production and exports over the last 25 years. Environmental sustainability in its production is becoming increasingly significant. This is due to consumers' growing awareness of the environment. Life cycle analysis of its industrial stage can be a useful tool to assess and improve the sustainability of its production. Therefore, this research seeks to obtain an environmental overview of the industrial process of a 700 mL bottle of 100% Reposado tequila aged for 6 months in oak barrels. The research showed that a bottle aged for 6 months generates 2.27 kg of CO 2 eq, an impact comparable to other spirits. The most impactful stages, responsible for most emissions, are bottling, distillation, cooking, and the agave farming phase. The low level of glass recycling in Mexico, the use of fuel oil, and the lack of clean energies aggravate the impact and increase emissions. The final conclusions highlight the need to increase the use of clean energy, reduce the use of fossil fuels, and promote recycling to improve sustainability.

Introduction Healthcare professionals play a critical role in providing affirmative care to gay and lesbian patients. However, their attitudes and practices can vary significantly depending on cultural and educational contexts. This study aimed to evaluate differences in affirmative practices among healthcare professionals in Poland and Spain, focusing on their approach to these patient groups, utilizing the Gay Affirmative Practice (GAP) Scale, as well as identifying key factors influencing these practices. Methods A cross-sectional study was conducted among healthcare professionals in Poland and Spain using the GAP Scale, which assesses beliefs and behaviors toward gay and lesbian patients. Data collection included 495 participants, with 205 from Spain and 290 from Poland. Descriptive statistics, Mann–Whitney tests, and multivariate regression analyses were used to identify factors associated with affirmative practices. Results Spanish participants scored significantly higher on both the beliefs and behaviors scales compared to Polish participants (p < 0.001 and p = 0.009, respectively). Gender of healthcare providers was a significant factor in both groups, with women demonstrating more affirmative beliefs than men. In the Polish group, being male was associated with a decrease in the belief scale score by an average of 6.572 points (regression coefficient = −6.572, p < 0.001), while attending LGBT-related training 1–2 times was associated with an increase of 5.356 points on the belief scale (regression coefficient = 5.356, p = 0.039). No significant independent predictors were identified for behaviors in the Polish group, as all p-values exceeded 0.05. Conclusion Spanish healthcare professionals showed more affirmative practices toward gay and lesbian patients than their Polish counterparts. Sex and gay and lesbian related training influenced beliefs, with male sex linked to lower affirmative practice in Poland. These findings highlight the need for systematic integration of gay and lesbian specific training into healthcare education programs to foster cultural competence and reduce disparities in patient care.

Arylethylamines are crucial elements in pharmaceutical molecules, making methods for their synthesis highly significant. The Truce–Smiles rearrangement is a well‐developed strategy to synthesize arylethylamine motifs via aryl migration. However, most examples require amide substrates to activate the alkene to attack by a radical precursor. This strategy both limits the product scope to amide‐containing compounds as well as necessitating the incorporation of specific functional groups arising from the initial radical addition. In this work, we overcome these limitations, delivering a hydrogen‐atom transfer from a cobalt catalyst to unactivated alkenes to yield β‐arylethylamines with simple alkyl chains. DFT studies reveal that increasing the steric hindrance in at least one of the ortho positions on the migrating aromatic group promotes ipso over ortho addition, a selectivity that contrasts with previous methods.

Introduction Suicidal behavior is a significant mental health concern among university students, yet it remains underexplored through a network approach. Traditional methods often overlook the complex interplay of psychological factors influencing suicidal behavior. This study addresses this gap by (a) examining suicidal behavior using network analysis and (b) identifying the psychological network of suicidal behavior along with protective and risk factors among university students. Method The sample consisted of a total of 1048 Spanish university students (M = 20.5 years; SD = 2.5; 58.2% women) from various universities. Several instruments were used to measure suicidal behavior, emotional and behavioral difficulties, prosocial behavior, subjective well‐being, emotional intelligence, self‐esteem, empathy, affect (both positive and negative), and emotional regulation. Data were analyzed using network analysis to understand the relationships among these variables. Results A total of 21.5% of the participants had experienced suicidal thoughts, 26.3% had wished to be dead or not wake up, 15% had considered specific suicide methods or made plans, and 5.8% had attempted suicide at least once. In addition, 18% had engaged in non‐suicidal self‐injury (NSSI) at least once. Network analysis revealed that suicidal behavior was highly interconnected with other psychological factors, with “considered taking own life” as the most influential node. Key factors included depressive symptoms, positive affect, and emotional intelligence. Suicidal behavior showed a positive connection with depressive symptoms and negative affect and a negative connection with self‐esteem and positive affect. Stability analysis confirmed the accuracy of the network estimations, indicating reliable insights into the psychological interconnections. Conclusions These findings indicate that suicidal behavior in university students is a complex, dynamic system shaped by cognitive, emotional, and affective factors. Network analysis, through advanced psychopathological and psychometric models, offers valuable insights into suicidal behavior, improving risk and protective factor assessment. This highlights the need for targeted and comprehensive prevention strategies in educational settings.

Background Livestock-associated (LA)-MRSA of CC398 lineage is related to the pig environment, although it also colonizes/infects humans. Tetracycline resistance (TETR) is a phenotypic marker of LA-MRSA-CC398. Objectives To determine the prevalence and changing epidemiology of LA-MRSA-CC398 in seven Spanish hospitals (H1–H7) located in areas with different pig farming densities (PFDs) (extremely high, very high, medium, and very low: EH/VH/M/VL), and to identify other non-CC398-LA-MRSA clones. Methods MRSA-TETR isolates (n = 165) obtained from hospitals H1–H7 over 6 months in 2023 were characterized with respect to genetic lineages/antimicrobial resistance and virulence/immune evasion cluster of CC398 and non-CC398. Results were compared with a previous multicentre study from 2016. Results We identified 86/165 MRSA-TETR isolates (52.1%) as being MRSA-CC398. A significant difference in MRSA-CC398/MRSA prevalence was detected between hospitals located in EH-PFD areas (H1 and H2, > 25%) and the one in a VL-PFD area (H7, 0%). Prevalences in the range 6.4%–12.2% were found in hospitals in M- and VH-PFD areas (H3–H6). Fourteen spa-types were identified among MRSA-CC398 isolates, with t011/t034 predominating (68.3%), followed by t1451/t1255 (13%). All but two MRSA-CC398 isolates were scn-negative (human adaptation marker). Among the 79 non-CC398-MRSA-TETR isolates, CC5, CC1 and CC8 predominated (45.6%, scn-negative). The prevalences of the scn gene among non-CC398-MRSA-TETR isolates in hospitals of EH-, VH-, M- and VL-PFD areas were 77.8%, 50%, 18.75% and 0%, respectively (significant correlation, P < 0.05). This study shows that MRSA-CC398 isolates are prevalent in hospitals located in EH-PFD areas but absent in the hospital of the VL-PFD area. Moreover, an increase in both PFD and prevalence of MRSA-CC398/MRSA in hospitals H3–H6 was observed in the 2023 study compared with the 2016 study. Conclusions A significant increase and more genetic diversity of predominant lineages of CC398-MRSA-TETR were observed in hospitals located in M- to VH-PFD areas.

Thiolate-protected gold nanoclusters (AuNCs) of sub-2 nm size have been synthesized through a novel bottom-up approach using the organometallic precursor [Au(C6F5)(tht)] (tht = tetrahydrothiophene) in a one-pot reaction under mild...

This article seeks to contribute to narrowing the gap between philological research and computational linguistics by providing a neural network model for Old English analysis. The article makes three key innovations: (i) the development of language-specific word embeddings derived directly from The Dictionary of Old English Corpus ; (ii) a comparative analysis of character-level versus word-level models that demonstrates the superior performance of character-level processing for morphologically rich historical languages; and (iii) a comprehensive Stanza-based pipeline that outperforms previous approaches to Old English parsing. Our model achieves 88.92% Unlabeled Attachment Score and 79.65% Labeled Attachment Score on dependency parsing tasks, which represents approximately 20 percentage point improvement over previous state-of-the-art multilingual approaches. The main conclusion of this work is that language-specific resources and character-level modeling are more effective for Old English processing than cross-linguistic transfer learning. This opens new avenues for computational research in historical linguistics and digital humanities.