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Background/aims: Corneal endothelial cell loss contributes to transplant failure. Autologous plasma products (APP) activate salvaging pathways that can prevent oxidative stress perioperatively. This study aimed to evaluate the safety of intraoperative incubation of full-thickness corneal grafts in platelet-rich plasma (aPRP) and plasma rich in growth factors (PRGF-Endoret) in mitigating postoperative corneal endothelial cell loss (ECL)., Methods: Pilot study including patients undergoing penetrating keratoplasty (PK) for various indications between June 2021 and December 2022. Patients were randomly assigned to receive either aPRP or PRGF-Endoret incubation, while those who declined intervention served as the control group. Demographic and clinical data were collected, including preoperative and postoperative endothelial cell count, intraocular pressure, pachymetry, and adverse reactions., Results: Thirty individuals who underwent PK completed follow-up: eight from the aPRP group, 10 from the PRGF-Endoret group, and 12 from the control group. No adverse events related to APP treatment were recorded. In the first and third postoperative months, the APP group had significantly lower ECL percentages (37% vs. 25%, p  = 0.02, and 44% vs. 33%, p  = 0.02, respectively); this trend was maintained in the sixth month. When stratified, the PRGF-Endoret group showed significant differences in ECL reduction compared to controls at both time points ( p  = 0.03 and p  = 0.05, respectively). The aPRP group showed a similar statistically significant outcome exclusively on the third postoperative month ( p  = 0.04). APP tended to reduce corneal edema faster than controls. Hexagonality was significantly better in the APP groups in the first and third months, particularly in the PRGF-Endoret group ( p  < 0.005)., Conclusion: Preoperative incubation with APP is safe and promotes better endothelial cell quality and quantity in the early postoperative period following PK. These findings suggest a potential clinical benefit in enhancing graft outcomes and warrant further investigation., Competing Interests: EO: J&J, Alcon, and Allergan. BS-C and EA: BTI-health. AS: Brill Pharma, Abbvie, and GlaxoSmithKline. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mercado, Hernández, Lopez-Rojas, De La Sen-Corcuera, Anitua, Barraquer, Gutiérrez, Otero and Sabater.)

In this paper we discuss the details, limitations, and difficulties of the implementation in hardware of a memristor-based random number generator that exhibits monofractal/multifractal behavior. To do so, the components and selection criteria of a reference memristor and one proposed by the authors, the chaotic circuit leveraging them, and the processing that is performed on the chaotic signals to achieve the random discrete sequences are described. After applying the estimation tools, findings indicate that more than 60% of the proposed combinations allow generating random discrete sequences, with long-range dependence, and that both monofractal and multifractal behaviors can also be obtained. Consequently, a hardware system was achieved that can be used as a source of entropy in future synthetic biological signal generators., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Cesar Hernandez reports administrative support and equipment, drugs, or supplies were provided by District University Francisco José de Caldas., (© 2024 The Authors.)

Background: Legg-Calvé-Perthes disease (LCPD) is a pediatric disorder that occurs due to the avascular necrosis of the femoral head and affects the range of motion of the hip in various degrees. Its etiology is still unknown, although it has been associated with coagulation abnormalities, however, the lack of reproducibility in the results in various studies has created a controversy as to whether hemostasis disorders are related to LCPD. On the other hand, there is little information on laboratory studies that could facilitate the diagnosis and treatment of LCPD., Methods: Blood and plasma samples were tested from 25 patients with LCPD and 50 healthy controls, matched by sex and age. Cellular markers were evaluated through complete blood count, as well as coagulation times, coagulation factors activity, antithrombotic proteins, and homocysteine concentration., Results: After assessing activity value frequencies in each group, the results showed more significant activity in some of the biological risk markers of thrombophilia, presenting a substantial difference in prothrombin time↘, FV↗, FVIII↗, FIX↗, and Hcy↗. These values imply that there may be hypercoagulable states in patients, which can cause thrombotic events., Conclusions: Diminished prothrombin time and increase in FV activity, FVIII, FIX, and Hcy concentration support the hypothesis that microthrombi formation in small-caliber vessels could be causing avascularity and femoral necrosis, which are traits of LCPD. In addition, based on our results, we believe that the laboratory studies carried out are very useful in the diagnosis and treatment of LCPD.

A potential alternative to the use of chemical products with oomyceticidal action for the control of Phytophthora capsici in vegetables is the use of antimicrobial metabolites, biosynthesized in Bacillus species. The objective of this study was to induce the biosynthesis of lipopeptides in Bacillus amyloliquefaciens KX953161.1 by using glutamic acid, iron, cellulose, chitin, or inactive Colletotrichum spp. cells. The in vitro oomyceticidal effect of the bacterial lipopeptides on zoospores of Phytophthora capsici was evaluated. The lipopeptides identified and quantified in the crude extracts by high performance thin layer chromatography (HPTLC) were fengycin and surfactin. The bacterial culture with inactive fungal cells yielded the greatest biosynthesis of lipopeptides, at 1847.02± 11.8 and 2563.45± 18.4 μg/ml of fengycin and surfactin, respectively and the treatments that obtained lower production of these lipopeptides, were those to which iron and cellulose were added with 608.05 ± 22.6 and 903.74± 22.1; 563.31± 11.9 and 936.96± 41.1 μg/ml for fengicin and surfactin, respectively. The lipopeptide extracted showed 100% germination inhibition on zoospores of P. capsici, revealing encystment, malformations in the germ tube and cellular degradation. Lipopeptides have the potential to control P. capsici; however, the biosynthesis of these lipopeptides requires further study to determine their biological mode of action and optimize lipopeptide performance and profile., (Copyright © 2022 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

"They are the same" is a phrase that teachers often hear from their students in arithmetic and algebra. But what do students mean when they say this? The present paper researches the notion of sameness within algebraic thinking in the context of generating equivalent numerical equalities. A group of Grade 6 Mexican students (10- to 12-year-olds) was presented with tasks that required transforming the given numerical equalities in such a way as to show their truth-value. The students initially indicated this by calculating and demonstrating that the total was the same on both sides. When asked not to calculate, their approaches evolved into more structural transformations involving decomposition so as to arrive at an equality with the same expression on each side. Students used the language of sameness-both visible and invisible-to describe the truth-value of their transformed expressions and equalities. The visible sameness referred to the resulting identical form of each side of the equality and the invisible sameness to the top-down equivalences that they had generated by their decomposing transformations-both types of sameness being characterized by their hidden numerical values. These findings suggest implications for transitioning to the algebraic domain of equations with their similarly hidden values., (© FIZ Karlsruhe 2022.)

Cognitive radio networks promote better spectral efficiency of the electric radio spectrum. The vast majority of current spectral decision models for cognitive radio networks evaluate their performance based on a single secondary user. In reality, the network can experience multiple requests from spectral opportunities. Based on this, the intent of this article is to present and evaluate a spectral decision model for cognitive radio networks in a multi-user environment taking into account the effect of the decisions of the SU on the usefulness of the other SU. To achieve this, a spectral decision model was developed that allows secondary users to share relevant information before accessing the spectrum so that they can select the most appropriate spectral opportunities. The evaluation and validation of the model was performed using three multicriteria decision-making algorithms under the metric of the number of total handoffs in a conventional scenario and a real scenario, in the conventional scenario, only users that match the input of the multiuser module are included; in the real scenario, in addition to the conventional users, users that enter and leave at random times are included, a feature that alters the models for estimating the behavior of the radio environment. The results show better performance of the TOPSIS algorithm over VIKOR and SAW. The most important contribution of this work is the evaluation of the performance of the spectral decision algorithms implemented in a multi-user environment that allows multiple access and exchange of information between users, with experimental spectral occupation data., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5 mg of FCT kg -1 of body weight (BW); sterile water (control); and ivermectine (0.22 mg kg -1 of BW) as chemical group. The data were processed through repeated measurement analysis. Even though the three FCT doses decreased (P < 0.05) the FEC, the highest reduction was obtained with 37.5 mg kg -1 of BW. No differences were observed in PCV and OMC. Higher ADG (P < 0.05) was observed with 37.5 mg kg -1 of BW of FCT. The count of adult nematodes (females and males) in the higher dose of FCT was similar to chemical treatment. Dose of 37.5 mg kg -1 of BW decreased the parasite infection and improved the lamb performance. Therefore, this dose could be used as a nutraceutic product in sheep production.

Background: Von Willebrand disease is the most common inherited disorder of the coagulation proteins in humans. There are three types: 1, 2A, 2B, 2N, 2M and 3. It is associated with mutations on chromosome 12 in the region p13.2, encoding the von Willebrand factor (VWF), which is synthesized in endothelial cells and megakaryocytes., Discussion: The VWF gene has been characterised using molecular biology techniques, which have acquired an important role in diagnosis von Willebrand disease, as well as in the investigation of alterations in other genes, which may be involved in regulating the synthesis, processing, and secretion of VWF. However, there are still no strategies to integrate the molecular biology diagnostic tests available. Analysis of VWF multimers is a methodology that meets the characteristics for diagnosis, but it is not easy to standardise. Considering that even in tertiary centres in our country, von Willebrand patients do not have a definitive diagnosis, it is necessary to implement these methodologies to study and improve diagnosis., Conclusions: Von Willebrand disease is highly heterogeneous due to the molecular mechanisms that produce the various clinical and laboratory phenotypes. In Mexico there are few studies related to this disease; therefore it is essential to conduct a comprehensive study including clinical, basic, and special testing laboratory tests, in order to establish a correct diagnosis, develop new therapeutic approaches, and offer the appropriate medical care and genetic counselling., (Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.)

Objective: To develop a technological tool that improves the initial learning of sign language in hearing impaired children., Methods: The development of this research was conducted in three phases: the lifting of requirements, design and development of the proposed device, and validation and evaluation device. Through the use of information technology and with the advice of special education professionals, we were able to develop an electronic device that facilitates the learning of sign language in deaf children. This is formed mainly by a graphic touch screen, a voice synthesizer, and a voice recognition system. Validation was performed with the deaf children in the Filadelfia School of the city of Bogotá., Results: A learning methodology was established that improves learning times through a small, portable, lightweight, and educational technological prototype., Conclusions: Tests showed the effectiveness of this prototype, achieving a 32 % reduction in the initial learning time for sign language in deaf children.

Background: Von Willebrand disease is an inherited disease in which the structure, function, and concentration of von Willebrand factor are altered, as well as the platelet von Willebrand factor endothelium interaction. In Mexico there are no epidemiological records of the disease. Only a few isolated studies have been reported from the clinical and hematological standpoint., Methods: We studied 155 Mexican Mestizos: 75 with presumptive diagnosis of von Willebrand disease, 15 with suspected diagnosis ofhemophilia A and 65 healthy donors (controls). Basic coagulation tests, special tests and classification test (analysis of multimeric composition) were carried out., Results: There were 15 patients with clinical diagnosis of hemophilia A, 75 patients with suspected von Willebrand disease of which 50 were diagnosed as the following types and subtypes: Type 1 (62%), Type 2 (22%) [subtypes: 2A (14%), 2B (2%), and 2N (6%)] and Type 3 (16%)., Conclusion: It has been reported that analysis of von Willebrand factor is a method that meets the characteristics for the diagnosis of von Willebrand disease. It is necessary to implement this methodology to study and improve the specific diagnoses.

Objective: This project was aimed at designing and putting an electronic prototype into practice for improving the initial time taken by visually handicapped people for learning Braille, especially children., Methods: This project was mainly based on a prototype digital electronic device which identifies and translates material written by a user in Braille by a voice synthesis system, producing artificial words to determine whether a handicapped person's writing in Braille has been correct. A global system for mobile communications (GSM) module was also incorporated into the device which allowed it to send text messages, thereby involving innovation in the field of articles for aiding visually handicapped people., Results: This project's main result was an easily accessed and understandable prototype device which improved visually handicapped people's initial learning of Braille., Conclusions: The time taken for visually handicapped people to learn Braille became significantly reduced whilst their interest increased, as did their concentration time regarding such learning.