Maintenance of systems with critical components. Prevention of early failures and wear-out

We present a model for inspection and maintenance of a system under two types of failures. Early failures (type I), affecting only a proportion p of systems, are due to a weak critical component detected by inspection. Type II failures are the result of the system ageing and preventive maintenance is used against them. The two novelties of this model are: (1) the use of a defective distribution to model strong components free of defects and thus immune to early failures. (2) the removal of the weak critical part once it is detected with no other type of rejuvenation of the system which constitutes an alternative to the minimal repair. We study the conditions under which this model outperforms, from a cost viewpoint, other two classical age-replacement models. The analysis reveals that inspection is advantageous if the system can function with the critical component in the defective state for a long enough time. The proportion of weak units and the quality of inspections also determine the optimum policy. The results about the range of application of the model are useful for decision making in actual maintenance. A case study concerning the timing belt of a four-stroke engine illustrates the model

Glyceraldehyde-3-phosphate dehydrogenase is posttranslationally modified by NAD+ in enterohemorrhagic Escherichia coli

Comunicaciones a congreso

Modelo de aprovechamiento de aguas lluvias en zonas de pobreza extrema

Las ventajas de captar agua lluvia en un entorno natural son: agua extremadamente limpia en comparación con otras fuentes de agua dulce disponibles, recurso esencialmente gratuito e independiente de empresas suministradoras habituales y que requiere de infraestructura sencilla para su captación, almacenamiento y distribución. El sistema de captación del agua lluvia permite almacenarla y posteriormente someter a tratamiento la que se utilizará para el consumo humano. A este sistema se le denomina CATDALL, que fue el prototipo resultado final del desarrollo del proyecto, gracias al apoyo del Fondo para la Investigación en Educación Superior (FIES) y la Universidad Tecnológica de El Salvador (UTEC). El prototipo puede ser replicable en otros centros escolares, que presenten escasez de agua bajo las circunstancias que fueren o como simple alternativa de ahorro aprovechando un recurso natural que es gratuito.Investigación desarrollada bajo el convenio FIES-UTEC, 2008-2009Universidad Tecnológica de El Salvado

Ocular penetration of fluorometholone-loaded PEG-PLGA nanoparticles functionalized with cell-penetrating peptides

Aim: Development of fluorometholone-loaded PEG-PLGA nanoparticles (NPs) functionalized with cellpenetrating peptides for the treatment of ocular inflammatory disorders. Materials & methods: Synthesized polymers and peptides were used for elaboration of functionalized NPs, which were characterized physicochemically. Cytotoxicity and ability to modulate the expression of proinflammatory cytokines were evaluated in vitro using human corneal epithelial cells (HCE-2). NP uptake was assayed in both in vitro and in vivo models. Results: NPs showed physicochemical characteristics suitable for ocular administration without evidence of cytotoxicity. TAT-NPs and G2-NPs were internalized and displayed anti-inflammatory activity in both HCE-2 cells and mouse eye. Conclusion: TAT-NPs and G2-NPs could be considered a novel strategy for the treatment of ocular inflammatory diseases of the anterior and posterior segment

Gel-Dispersed Nanostructures Lipid Carriers Loading Thymol Designed for Dermal Pathologies

Purpose: Acne vulgaris is one of the most prevalent dermal disorders affecting skin health and appearance. To date, there is no effective cure for this pathology, and the majority of marketed formulations eliminate both healthy and pathological microbiota. Therefore, hereby we propose the encapsulation of an antimicrobial natural compound (thymol) loaded into lipid nanostructured systems to be topically used against acne.Methods: To address this issue, nanostructured lipid carriers (NLC) capable of encapsulating thymol, a natural compound used for the treatment of acne vulgaris, were developed either using ultrasonication probe or high-pressure homogenization and optimized using 22-star factorial design by analyzing the effect of NLC composition on their physicochemical parameters. These NLC were optimized using a design of experiments approach and were characterized using different physicochemical techniques. Moreover, short-term stability and cell viability using HaCat cells were assessed. Antimicrobial efficacy of the developed NLC was assessed in vitro and ex vivo.Results: NLC encapsulating thymol were developed and optimized and demonstrated a prolonged thymol release. The formulation was dispersed in gels and a screening of several gels was carried out by studying their rheological properties and their skin retention abilities. From them, carbomer demonstrated the capacity to be highly retained in skin tissues, specifically in the epidermis and dermis layers. Moreover, antimicrobial assays against healthy and pathological skin pathogens demonstrated the therapeutic efficacy of thymol-loaded NLC gelling systems since NLC are more efficient in slowly reducing C. acnes viability, but they possess lower antimicrobial activity against S. epidermidis, compared to free thymol.Conclusion: Thymol was successfully loaded into NLC and dispersed in gelling systems, demonstrating that it is a suitable candidate for topical administration against acne vulgaris by eradicating pathogenic bacteria while preserving the healthy skin microbiome.</p

Normal reference values of strength in pelvic floor muscle of women: a descriptive and inferential study

Background: To describe the clinical, functional and quality of life characteristics in women with Stress Urinary Incontinence (SUI). In addition, to analyse the relationship between the variables reported by the patients and those informed by the clinicians, and the relationship between instrumented variables and the manual pelvic floor strength assessment.Methods: Two hundred and eighteen women participated in this observational, analytical study. An interview about Urinary Incontinence and the quality of life questionnaires (EuroQoL-5D and SF-12) were developed as outcomes reported by the patients. Manual muscle testing and perineometry as outcomes informed by the clinician were assessed. Descriptive and correlation analysis were carried out.Results: The average age of the subjects was (39.93 ± 12.27 years), (24.49 ± 3.54 BMI). The strength evaluated by manual testing of the right levator ani muscles was 7.79 ± 2.88, the strength of left levator ani muscles was 7.51 ± 2.91 and the strength assessed with the perineometer was 7.64 ± 2.55. A positive correlation was found between manual muscle testing and perineometry of the pelvic floor muscles (p < .001). No correlation was found between outcomes of quality of life reported by the patients and outcomes of functional capacity informed by the physiotherapist.Conclusion: A stratification of the strength of pelvic floor muscles in a normal distribution of a large sample of women with SUI was done, which provided the clinic with a baseline. There is a relationship between the strength of the pelvic muscles assessed manually and that obtained by a perineometer in women with SUI. There was no relationship between these values of strength and quality of life perceived

Safety and effectiveness of isavuconazole in real-life non-neutropenic patients

Objectives: Information is scarce on clinical experiences with non-neutropenic patients with invasive fungal infection (IFI) receiving isavuconazole. We aimed to report the safety and effectiveness of this drug as a first-line treatment or rescue in real life. Methods: A retrospective, observational multicentric study of non-neutropenic patients who received isavuconazole as an IFI treatment at 12 different university hospitals (January 2018-2022). All patients met criteria for proven, probable or possible IFI according to EORTC-MSG. Results: A total of 238 IFIs were treated with isavuconazole during the study period. Combination therapy was administered in 27.7% of cases. The primary IFI was aspergillosis (217, 91.2%). Other IFIs treated with isavuconazole were candidemia (n = 10), mucormycosis (n = 8), histoplasmosis (n = 2), cryptococcosis (n = 2), and others (n = 4). Median time of isavuconazole treatment was 29 days. Only 5.9% (n = 14) of cases developed toxicity, mainly hepatic-related (10 patients, 4.2%). Nine patients (3.8%) had treatment withdrawn. Successful clinical response at 12 weeks was documented in 50.5% of patients. Conclusion: Isavuconazole is an adequate treatment for non-neutropenic patients with IFIs. Toxicity rates were low and its effectiveness was comparable to other antifungal therapies previously reported. (c) 2024 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/

Assessment of a primary care-based telemonitoring intervention for home care patients with heart failure and chronic lung disease. The TELBIL study

<p>Abstract</p> <p>Background</p> <p>Telemonitoring technology offers one of the most promising alternatives for the provision of health care services at the patient's home. The primary aim of this study is to evaluate the impact of a primary care-based telemonitoring intervention on the frequency of hospital admissions.</p> <p>Methods/design</p> <p>A primary care-based randomised controlled trial will be carried out to assess the impact of a telemonitoring intervention aimed at home care patients with heart failure (HF) and/or chronic lung disease (CLD). The results will be compared with those obtained with standard health care practice. The duration of the study will be of one year. Sixty patients will be recruited for the study. In-home patients, diagnosed with HF and/or CLD, aged 14 or above and with two or more hospital admissions in the previous year will be eligible.</p> <p>For the intervention group, telemonitoring will consist of daily patient self-measurements of respiratory-rate, heart-rate, blood pressure, oxygen saturation, weight and body temperature. Additionally, the patients will complete a qualitative symptom questionnaire daily using the telemonitoring system. Routine telephone contacts will be conducted every fortnight and additional telephone contacts will be carried out if the data received at the primary care centre are out of the established limits. The control group will receive usual care. The primary outcome measure is the number of hospital admissions due to any cause that occurred in a period of 12 months post-randomisation. The secondary outcome measures are: duration of hospital stay, hospital admissions due to HF or CLD, mortality rate, use of health care resources, quality of life, cost-effectiveness, compliance and patient and health care professional satisfaction with the new technology.</p> <p>Discussion</p> <p>The results of this study will shed some light on the effects of telemonitoring for the follow-up and management of chronic patients from a primary care setting. The study may contribute to enhance the understanding of alternative modes of health care provision for medically unstable elderly patients, who bear a high degree of physical and functional deterioration.</p> <p>Trial Registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN89041993">ISRCTN89041993</a></p

Megascopic Quantum Phenomena. A Critical Study of Physical Interpretations

A megascopic revalidation is offered providing responses and resolutions of current inconsistencies and existing contradictions in present-day quantum theory. As the core of this study we present an independent proof of the Goldstone theorem for a quantum field formulation of molecules and solids. Along with phonons two types of new quasiparticles appear: rotons and translons. In full analogy with Lorentz covariance, combining space and time coordinates, a new covariance is necessary, binding together the internal and external degrees of freedom, without explicitly separating the centre-of-mass, which normally applies in both classical and quantum formulations. The generally accepted view regarding the lack of a simple correspondence between the Goldstone modes and broken symmetries, has significant consequences: an ambiguous BCS theory as well as a subsequent Higgs mechanism. The application of the archetype of the classical spontaneous symmetry breaking, i.e. the Mexican hat, as compared to standard quantum relations, i.e. the Jahn-Teller effect, superconductivity or the Higgs mechanism, becomes a disparity. In short, symmetry broken states have a microscopic causal origin, but transitions between them have a teleological component. The different treatments of the problem of the centre of gravity in quantum mechanics and in field theories imply a second type of Bohr complementarity on the many-body level opening the door for megascopic representations of all basic microscopic quantum axioms with further readings for teleonomic megascopic quantum phenomena, which have no microscopic rationale: isomeric transitions, Jahn-Teller effect, chemical reactions, Einstein-de Haas effect, superconductivity-superfluidity, and brittle fracture.Comment: 117 pages, 17 sections, final revised version from 20 May 2019 but uploaded after the DOI was know