Blockchain Technology for Sustainable Supply Chains: A Bibliometric Study

Javier RAMÍREZ(Javier RAMÍREZ ),Girlesa GALLEGO(Girlesa GALLEGO ),William NIEBLES-NÚÑEZ(William NIEBLES-NÚÑEZ ),Johny García TIRADO(Johny García TIRADO ) 한국유통과학회 2023 유통과학연구 Vol.21 No.6

CtIP interacts with TopBP1 and Nbs1 in the response to double-stranded DNA breaks (DSBs) in Xenopus egg extracts.

Ramí,rez-Lugo, Juan S,Yoo, Hae Yong,Yoon, Su Jin,Dunphy, William G Landes Bioscience 2011 Cell cycle Vol.10 No.3

<P>In the presence of double-stranded DNA breaks (DSBs), the activation of ATR is achieved by the ability of ATM to phosphorylate TopBP1 on serine 1131, which leads to an enhancement of the interaction between ATR and TopBP1. In Xenopus egg extracts, the Mre11-Rad50-Nbs1 (MRN) complex is additionally required to bridge ATM and TopBP1 together. In this report, we show that CtIP, which is recruited to DSB-containing chromatin, interacts with both TopBP1 and Nbs1 in a damage-dependent manner. An N-terminal region containing the first two BRCT repeats of TopBP1 is essential for the interaction with CtIP. Furthermore, two distinct regions in the N-terminus of CtIP participate in establishing the association between CtIP and TopBP1. The first region includes two adjacent putative ATM/ATR phosphorylation sites on serines 273 and 275. Secondly, binding is diminished when an MRN-binding region spanning residues 25-48 is deleted, indicative of a role for the MRN complex in mediating this interaction. This was further evidenced by a decrease in the interaction between CtIP and TopBP1 in Nbs1-depleted extracts and a reciprocal decrease in the binding of Nbs1 to TopBP1 in the absence of CtIP, suggestive of the formation of a complex containing CtIP, TopBP1, and the MRN complex. When CtIP is immunodepleted from egg extracts, the activation of the response to DSBs is compromised and the levels of ATR, TopBP1, and Nbs1 on damaged chromatin are reduced. Thus, CtIP interacts with TopBP1 in a damage-stimulated, MRN-dependent manner during the activation of ATR in response to DSBs.</P>

Active Disturbance Rejection Control of the Inertia Wheel Pendulum through a Tangent Linearization Approach

Mario Ramírez-Neria,Hebertt Sira-Ramírez,Rubén Garrido-Moctezuma,Alberto Luviano-Juárez 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.1

A flatness based approach is proposed for the linear Active Disturbance Rejection Control (ADRC) stabilizationof a nonlinear inertia wheel pendulum (IWP) around its unstable equilibrium point, subject to unmodelleddynamics and disturbances. The approach exploits the cascade structure, provided by the flatness property, of thetangent linearization of the underactuated system which allows designing a high gain linear cascaded Extended StateObserver (ESO) of the Generalized Proportional Integral (GPI) type. This class of linear observers is employed tobuild an Active Disturbance Rejection Control controller with a lower order of complexity regarding other ADRCclassic schemes. Experimental results demonstrate the effectiveness and feasibility of the proposed approach, aswell as a better behavior with respect to a classic control technique in the presence of disturbances.

Challenges managing COVID vaccine-induced immune thrombotic thrombocytopenia in low-middle income countries

Céleo Ramírez,Ramón Jeremías Soto Hernández,Reyna M. Durón 대한백신학회 2021 Clinical and Experimental Vaccine Research Vol.10 No.3

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is an extremely rare complication associated with the adenovirus-vectored coronavirus disease 2019 (COVID-19) ChAdOx1 nCoV-19 (AZD1222) vaccine. It is characterized by venous thrombosis, mainly cerebral venous sinus thrombosis, moderate to severe thrombocytopenia, and rarely, thrombosis in cerebral arteries. This syndrome is similar to the heparin-induced thrombocytopenia and presents mostly among women aged 18–55 years, without previous exposure to heparin, usually 5 to 20 days after vaccination. However, cases have been reported in men and older adults [1-4]. Unlike COVID-19, this adverse effect might not represent a public health problem in itself, but it is already causing vaccine hesitancy in population groups susceptible to severe COVID-19, and poses a challenge in low resource settings [5]. The first case reports showed evidence that VITT has a mortality around 40% [1-3]. So far, cases have been reported and treated in hospitals of highly developed countries with first-rate health systems that facilitate early detection and treatment of this severe adverse event. VITT is confirmed by using PF4-dependent enzyme-linked immunosorbent assay (ELISA) assay, which allows the differential diagnosis from other causes of thrombosis in patients with a history of ChAdOx1 nCoV-19 vaccination in previous days. However, it is likely that a large number of hospitals in many low-middle income countries do not have approved PF4-dependent ELISA assays for accurate diagnosis, nor immunoglobulins, glucocorticoids, and non-heparin anticoagulants needed for the treatment of this condition [1-4]. In times of this COVID-19 pandemic and precision medicine, problems and solutions should be considered global. Policies related to COVID-19 need to be addressed considering varied public health and socioeconomic contexts. The ChAdOx1 nCoV-19 vaccine is one of the most used vaccines in low-middle income countries, where special testing to confirm VITT is not widely available. Therefore, real figures are unknown, and underreporting of this adverse effect should be considered. Patient information, government, and hospital preparedness in these countries are needed to diagnose and manage VITT adequately, and to reduce morbidity and mortality from this complication. These strategies will have a positive impact on public acceptance and adherence to COVID vaccination.

Diet-induced obese mice exhibit altered immune responses to early Salmonella Typhimurium oral infection

Ricardo Ernesto Ramírez-Orozco,Elena Franco Robles,Victoriano Pérez Vázquez,Joel Ramírez Emiliano,Marco Antonio Hernández Luna,Sergio López Briones 한국미생물학회 2018 The journal of microbiology Vol.56 No.9

Obesity is a chronic disease associated with different metabolic diseases as well as alterations in immune cell function. It is characterized by a chronic systemic low grade inflammation. There are several studies demonstrating the influence of obesity on the impaired immune response to infection. However, it is not completely clear whether the obese environment influences the development or maintenance of the immune response against infections. The aim of this study was to determine how obesity induced by a high-fat diet affects the immune response to an early oral Salmonella infection. Four groups of mice were kept in separate cages. Two of these designated as controls, fed with a normal diet; whereas other two groups were fed with a high fat diet for 10 weeks. Some mice were used for Salmonella oral infection. After 7 days of oral infection with S. Thypimurium the proportions of spleen cell subsets expressing activation markers in normal diet and HFD obese mice were stained with monoclonal antibodies and analyzed by flow cytometry. Also, mRNA levels of different cytokines were quantified by RT-PCR. It was found that obesity affects the function of the immune system against an early oral Salmonella infection, decreasing NK cells, altering the expression of activation molecules as well as cytokines mRNA levels. Interestingly, the expression some activation molecules on T lymphocytes was reestablished after Salmonella infection, but not the CD25 expression. Immune alterations could lead to immunosuppression or increased susceptibility to infections in HFD obese mice.

PLASMON RESONANCE AND RAMAN MODES IN Pb NANOPARTICLES OBTAINED IN EXTRACT OF OPUNTIA FICUS-INDICA PLANT

L. P. RAMÍREZ-RODRÍGUEZ,M. CORTEZ-VALADEZ,H. ARIZPE-CH AVEZ,J.-G. BOCARANDO-CHACON,R. RAMÍREZ-BON,S. VELUMANI,M. FLORES-ACOSTA 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.6

Colloidal nanoparticles were obtained by green synthesis, embedded in the Opuntia ¯cus-indicaplant extract. Optical measurements allowed us to detect two absorption bands centered in230 nm and 298 nm. Agglomerates of Pb nanoparticles have size in the range 2 – 8 nm. The ef-fective absorption cross section of spherical Pb nanoparticles was calculated by applying the Mietheory for colloidal systems and compared to optical absorption measurements of Pb nano-particles. The Raman spectrum of the samples after the reduction of Pb, shows a band at lowwavenumbers centered at 116 cm? 1 . Similar bands have been assigned to small Pb and Agclusters in other experimental results. Additionally, we used the density functional theory (DFT)as well as semi-empirical methods to assign this band to radial breathing modes of Pb metalnanoparticles.

Enteroparasitism and Risk Factors Associated with Clinical Manifestations in Children and Adults of Jalisco State in Western Mexico

María de la Luz Galván-Ramírez,Ana Luisa Madriz-Elisondo,Jorge de Jesús Romero Rameño,Dania Araceli de la O Carrasco,Marco Antonio Cardona López,Cynthia Guadalupe Temores Ramírez 질병관리본부 2019 Osong Public Health and Research Persptectives Vol.10 No.1

Objectives: To determine the prevalence and risk factors associated with intestinal parasites in the population of San Juan Cosala, Jalisco, Mexico. Methods: A total of 277 samples from 104 participants were analysed using direct smear, flotation, formaldehyde/ethyl acetate, and modified Kinyoun’s acid-fast stain methods. The Graham method was applied only for samples from children under 12 years of age for the diagnosis of Enterobius vermicularis. Results: The prevalence of parasite infections in the study population was 77.9% including: Entamoeba histolytica/E. dispar/E. moshkovskii/E. bangladeshi (37.5%), Giardia intestinalis (11.5%); commensals: Endolimax nana (44.2%), Entamoeba coli (27.9%), Chilomastix mesnili (6.7%) and Iodamoeba bütschlii, (2.9%); emerging intestinal protozoans: Blastocystis spp. (49%), Cryptosporidium spp. (7.7%) and Cyclospora cayetanensis (2.9%); and helminths: Enterobius vermicularis (18.3%) and Ascaris lumbricoides (5.8%). The results also showed that 58.64% of the studied population presented polyparasitism. A significant association was found between protozoan infections and housewives, and houses that were not built with concrete ceilings, brick walls and cement floors (p < 0.05). Conclusion: Polyparasitism was observed in over half the study population. The most prevalent parasite was Blastocystis spp, whilst the prevalence of helminths was less than that of protozoans. The risk factors for infection to intestinal parasites were being a housewife and not having solid brick, cement and concrete materials for house construction.

Assessment of buccal bone thickness of aesthetic maxillary region: a conebeam computed tomography study

Ramón Fuentes,Tania Flores,Pablo Navarro,Carlos Salamanca,Víctor Beltrán,Eduardo Borie 대한치주과학회 2015 Journal of Periodontal & Implant Science Vol.45 No.5

Purpose: The aim of this study was to analyze the anatomical dimensions of the buccal bone walls of the aesthetic maxillary region for immediate implant placement, based upon cone-beam computed tomography (CBCT) scans in a sample of adult patients. Methods: Two calibrated examiners analyzed a sample of 50 CBCT scans, performing mor¬phometric analyses of both incisors and canines on the left and right sides. Subsequently, in the sagittal view, a line was traced through the major axis of the selected tooth. Then, a second line (E) was traced from the buccal to the palatal wall at the level of the observed bone ridges. The heights of the buccal and palatal bone ridges were determined at the ma¬jor axis of the tooth. The buccal bone thickness was measured across five lines. The first was at the level of line E. The second was at the most apical point of the tooth, and the other three lines were equidistant between the apical and the cervical lines, and parallel to them. Statistical analysis was performed with a significance level of P≤0.05 for the bone thick¬ness means and standard deviations per tooth and patient for the five lines at varying depths. Results: The means of the buccal wall thicknesses in the central incisors, lateral incisors and canines were 1.14±0.65 mm, 0.95±0.67 mm and 1.15±0.68 mm, respectively. Additionally, only on the left side were significant differences in some measurements of buccal bone thickness observed according to age and gender. However, age and gender did not show significant differences in heights between the palatal and buccal plates. In a few cases, the buccal wall had a greater height than the palatal wall. Conclusions: Less than 10% of sites showed more than a 2-mm thickness of the buccal bone wall, with the exception of the central incisor region, wherein 14.4% of cases were ≥2 mm.

Antimicrobial Activity of Northwestern Mexican Plants Against Helicobacter pylori

Ramón E. Robles-Zepeda,Carlos A. Velázquez-Contreras,Adriana Garibay-Escobar,Juan C. Gálvez-Ruiz,Eduardo Ruiz-Bustos 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.10

Helicobacter pylori is the major etiologic agent of such gastric disorders as chronic active gastritis and gastric carcinoma. Over the past few years, the appearance of antibiotic-resistant bacteria has led to the development of better treatments, such as the use of natural products. This study evaluated the anti–H. pylori activity of 17 Mexican plants used mainly in the northwestern part of Mexico (Sonora) for the empirical treatment of gastrointestinal disorders. The anti–H. pylori activity of methanolic extracts of the plants was determined by using the broth microdilution method. The 50% minimum inhibitory concentrations ranged from less than 200 to 400 μg/mL for Castella tortuosa, Amphipterygium adstringens, Ibervillea sonorae, Pscalium decompositum, Krameria erecta, Selaginella lepidophylla, Pimpinella anisum, Marrubium vulgare, Ambrosia confertiflora, and Couterea latiflora and were greater than 800 μg/mL for Byophyllum pinnatum, Tecoma stans linnaeus, Kohleria deppena, Jatropha cuneata, Chenopodium ambrosoides, and Taxodium macronatum. Only Equisetum gigantum showed no activity against H. pylori. This study suggests the important role that these plants may have in the treatment of gastrointestinal disorders caused by H. pylori. The findings set the groundwork for further characterization and elucidation of the active compounds responsible for such activity.

Systematic Design of High-Resolution High-Frequency Cascade Continuous-Time Sigma-Delta Modulators

Ramón Tortosa,Rafael Castro-López,Elisenda Roca,Ángel Rodríguez-Vázquez,F.V. Fernández 한국전자통신연구원 2008 ETRI Journal Vol.30 No.4

This paper introduces a systematic top-down and bottom-up design methodology to assist the designer in the implementation of continuous-time (CT) cascade sigmadelta (ΣΔ) modulators. The salient features of this methodology are (a) flexible behavioral modeling for optimum accuracy-efficiency trade-offs at different stages of the top-down synthesis process, (b) direct synthesis in the continuous-time domain for minimum circuit complexity and sensitivity, (c) mixed knowledge-based and optimization-based architectural exploration and specification transmission for enhanced circuit performance, and (d) use of Pareto-optimal fronts of building blocks to reduce re-design iterations. The applicability of this methodology will be illustrated via the design of a 12-bit 20 MHz CT ΣΔ modulator in a 1.2 V 130 nm CMOS technology.