Juan Rulfo : Su vida, su tiempo y su obra

Sergio Lopez Mena 서울대학교 스페인중남미연구소 2005 이베로아메리카硏究 Vol.16 No.-

En la narrativa mexicana del siglo XX, en la que destacan Mariano Azuela, Martín Luis Guzmán, José Revueltas, Agustín Yáñez, Juan José Arreola y Juan Rulfo, este último sobresale por la autenticidad de su lenguaje y el carácter renovador de sus propuestas literarias. La vida de Rulfo abarca una etapa crucial de la historia contemporánea de México, la de la institucionalización de la Revolución Mexicana, época en que florece culturalmente el nacionalismo. En sus cuentos, expresión de una mentalidad de los hombres del campo, Rulfo construyó con intensidad seres en situación límite, con la violencia como signo más evidente. En su novela Pedro Páramo, está la idiosincrasia de un amplio grupo social, pero además la profundización en los misterios del hombre universal, particularmente en la veta de la pasión amorosa. Novela dialógica, desprovista del tradicional punto de vista moralizante, es Pedro Páramo una obra auténtica, de fina poesía. Por otra parte, la obra fotográfica de Rulfo, que lo muestra como un experto en ese arte, da testimonio del México de todos los tiempos, con la pobreza de su gente, la aridez de sus campos, la ternura de sus indígenas.

Efficacy of topical interventions for temporomandibular disorders compared to placebo or control therapy: a systematic review with meta-analysis

Mena, Mariam,Dalbah, Lana,Levi, Lauren,Padilla, Mariela,Enciso, Reyes The Korean Dental Society of Anesthsiology 2020 Journal of Dental Anesthesia and Pain Medicine Vol.20 No.6

This systematic review focused on the efficacy of topical products in reducing temporomandibular joint disorder (TMD)-associated pain, in comparison to placebo or control interventions. The EMBASE, Web of Science, Cochrane Library, and MEDLINE via PubMed databases were searched for randomized controlled trials (RCTs) using topical interventions in adults diagnosed with TMD. The pain intensity was the primary outcome, and other clinical findings were the secondary outcomes. The risk of bias was evaluated according to the Cochrane's handbook. The search up to February 7, 2020 identified a total of 496 unduplicated references. Nine RCTs with 355 adult patients diagnosed with TMD were included. The meta-analysis did not show a significant reduction in baseline pain intensity in the nonsteroidal anti-inflammatory drug (NSAIDs) group, when compared to the placebo group (P = 0.288). One study demonstrated a statistically significant pain score decrease for Theraflex-TMJ compared to placebo after 10 d of treatment (P = 0.003) and follow-up, 5 d after the last application (P = 0.027). Ping On reduced pain at 4 weeks of application (P < 0.001) but not after 7 d of application (P = 0.136). In one study, cannabidiol (CBD) significantly improved the pain intensity compared to placebo (P < 0.001). However, no differences were found with capsaicin in the two studies (P = 0.465). Evidence was of low quality because the studies were considered as having an unclear or a high risk of bias and a small number of studies were analyzed. The evidence is not sufficient to support the use of topical NSAIDs and capsaicin, and limited evidence was found for Threraflex-TMJ, bee venom, Ping On, and CBD, with only one study reporting for each. Additional studies are recommended to validate these results.

The quantum universe: philosophical foundations and oriental medicine

Menas Kafatos,Keun-Hang Yang 한국한의학연구원 2016 Integrative Medicine Research Vol.5 No.4

The existence of universal principles in both science and medicine implies that one can explore their common applicability. Here we explore what we have learned from quantum mechanics, phenomena such as entanglement and nonlocality, the role of participation of the observer, and how these may apply to oriental medicine. The universal principles of integrated polarity, recursion, and creative interactivity apply to all levels of existence and all human activities, including healing and medicine. This review examines the possibility that what we have learned from quantum mechanics may provide clues to better understand the operational principles of oriental medicine in an integrated way. Common to both is the assertion that Consciousness is at the foundation of the universe and the inner core of all human beings. This view goes beyond both science and medicine and has strong philosophical foundations in Western philosophy as well as monistic systems of the East.

Hydrology and Drought: Past Relationships and Future Challenges

Menas C. Kafatos 한국기상학회 2015 한국기상학회 학술대회 논문집 Vol.2015 No.10

A Detection Method of Ectocervical Cell Nuclei for Pap test Images, Based on Adaptive Thresholds and Local Derivatives

Julio Oscanoa,Marcelo Mena,Guillermo Kemper 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.2

Cervical cancer is one of the main causes of death by disease worldwide. In Peru, it holds the first place in frequency and represents 8% of deaths caused by sickness. To detect the disease in the early stages, one of the most used screening tests is the cervix Papanicolaou test. Currently, digital images are increasingly being used to improve Pap test efficiency. This work develops an algorithm based on adaptive thresholds, which will be used in Pap smear assisted quality control software. The first stage of the method is a pre-processing step, in which noise and background removal is done. Next, a block is segmented for each one of the points selected as not background, and a local threshold per block is calculated to search for cell nuclei. If a nucleus is detected, an artifact rejection follows, where only cell nuclei and inflammatory cells are left for the doctors to interpret. The method was validated with a set of 55 images containing 2317 cells. The algorithm successfully recognized 92.3% of the total nuclei in all images collected.

Endodontic treatment of mandibular molar with root dilaceration using Reciproc single-file system

Daniely Amorin Meireles,Mariana Mena Barreto Bastos,André Augusto Franco Marques,Lucas da Fonseca Roberti Garcia,Emílio Carlos Sponchiado Júnior 大韓齒科保存學會 2013 Restorative Dentistry & Endodontics Vol.38 No.3

Biomechanical preparation of root canals with accentuated curvature is challenging. New rotatory systems, such as Reciproc, require a shorter period of time to prepare curved canals, and became a viable alternative for endodontic treatment of teeth with root dilaceration. Thus, this study aimed to report a clinical case of endodontic therapy of root with accentuated dilaceration using Reciproc single-file system. Mandibular right second molar was diagnosed as asymptomatic irreversible pulpitis. Pulp chamber access was performed, and glide path was created with #10 K-file (Dentsply Maillefer)and PathFile #13, #16 and #19 (Dentsply Maillefer) up to the temporary working length. The working length measured corresponded to 20 mm in the mesio-buccal and mesio-lingual canals, and 22 mm in the distal canal. The R25 file (VDW GmbH) was used in all the canals for instrumentation and final preparation, followed by filling with Reciproc gutta-percha cones (VDW GmbH) and AH Plus sealer (Dentsply Maillefer),using thermal compaction technique. The case has been receiving follow-up for 6mon and no painful symptomatology or periapical lesions have been found. Despite the difficulties, the treatment could be performed in a shorter period of time than the conventional methods.

Transepithelial Laser versus Alcohol Assisted Photorefractive Keratectomy Safety and Efficacy: 1-Year Follow-up of a Contralateral Eye Study

Hesham Mohamed Gharieb,Mo’mena Ahmad A Awad-Allah,Anas Adel Ahmed,Ihab Saad Othman 대한안과학회 2021 Korean Journal of Ophthalmology Vol.35 No.2

Purpose: To compare single-step transepithelial photorefractive keratectomy (TPRK) to conventional alcohol assisted epithelialremoval then photorefractive keratectomy (AAPRK) regarding pain, epithelial healing, visual acuity, corneal haze measuredsubjectively and objectively, higher order aberrations changes, contrast sensitivity and vector analysis of astigmatic correctionwith one year follow-up. Methods: A prospective double-blind randomized study of 29 subjects (58 eyes) who underwent myopic aberration-freelaser correction by smart pulse technology using Schwind Amaris 1050 Hz with 1-year follow-up. Right eye was randomlytreated by AAPRK or TPRK. Postoperative assessment was performed on day 1 and 3, at 1st week, and 1st, 3rd, 6th, and 12thmonths. Patients were assessed for pain, epithelial healing, visual acuity, corneal haze, astigmatic correction, higher order aberrationsand contrast sensitivity. Results: Epithelial healing was complete by the 3rd day in 62.1% of AAPRK eyes and in 89.7% of TPRK eyes. First day postoperativepain was higher in TPRK group (p = 0.0134). The decimal uncorrected visual acuity at 12 months was 1.47 ± 0.39 and1.57 ± 0.38 in the AAPRK and TPRK groups respectively (p = 0.3719). Post-photorefractive keratectomy haze reached a finallevel of 0.04 ± 0.14 and 0.02 ± 0.1 in AAPRK and TPRK groups respectively (p = 0.5607). Contrast sensitivity was comparable inlow and high frequency cycles per degree. Vector analysis of astigmatic correction showed correction index at one year of 0.99and 1.05 for AAPRK and TPRK groups respectively. Conclusions: Alcohol assisted and transepithelial photorefractive keratectomy have comparable results regarding safety andefficacy.

Patterning of parallel nanobridge structures by reverse nanostencil lithography using an edge-patterned stencil

Park, Chan Woo,Mena, Oscar Vazquez,Brugger, Jü,rgen IOP Pub 2007 Nanotechnology Vol.18 No.4

<P>We propose a new process for forming parallel nanobridge patterns by nanostencil lithography. In this process, a low-stress silicon nitride stencil with parallel nanobridge structures is fabricated by a new edge patterning technique where those nanobridges are formed simultaneously via sidewall features using the conventional photolithography and anisotropic dry etching process. After forming primary Cr patterns on the oxidized Si substrate by depositing Cr through the edge-patterned stencil, those patterns are transferred onto the underlying Si layer in a reversed manner, leading to the formation of parallel Cr nanobridge patterns on the Si substrate. Using this process, we have successfully produced 85 nm-wide parallel Cr nanobridge patterns from a stencil with 115 nm-wide nanobridge structures that was fabricated by conventional microlithography. As there is no need for advanced lithography techniques in preparing the nanobridge stencil, the combination of the edge patterning and reverse nanostencil process provides a cost-effective tool for the massive fabrication of parallel nanobridge arrays at the 100 nm scale. </P>

Effect of Fiber Orientation on the Fatigue Behavior of Steel Fiber-Reinforced Concrete Specimens by Performing Wedge Splitting Tests and Computed Tomography Scanning

Dorys C. González,Álvaro Mena-Alonso,Jesús Mínguez,José A. Martínez,Miguel A. Vicente 한국콘크리트학회 2024 International Journal of Concrete Structures and M Vol.18 No.2

This paper shows the relationship, in steel fiber-reinforced concrete, between fiber orientation and fatigue response through the combined use of computed tomography (CT), digital image processing (DIP) software and wedge splitting test (WST). The WST cubes were extracted from conventional 150 × 150× 600 concrete prisms and a groove and notch were carved on different faces in such a way that in half of the test specimens the fibers are oriented mostly perpendicular to the breaking surface and, in the other half, the fibers are mostly oriented parallel to the breaking surface. Fiber orientation was obtained using a CT device and DIP software from a miniprism extracted from the previously mentioned concrete prisms. The results show that there is a strong correlation between the crack-sewing fiber orientation on the one hand and fatigue life and crack opening rate per cycle on the other hand. Cubes with a higher percentage of fibers perpendicular to the crack surface (i.e., with a higher efficiency index) show a longer fatigue life and a lower crack opening rate per cycle, while cubes with a lower efficiency index show a shorter fatigue life and a higher crack opening rate per cycle.

Efficient Cobalt Catalyst for Ambient-Temperature Nitrile Dihydroboration, the Elucidation of a Chelate-Assisted Borylation Mechanism, and a New Synthetic Route to Amides

Ghosh, Chandrani,Kim, Suyeon,Mena, Matthew R.,Kim, Jun-Hyeong,Pal, Raja,Rock, Christopher L.,Groy, Thomas L.,Baik, Mu-Hyun,Trovitch, Ryan J. American Chemical Society 2019 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.141 No.38

<P><I>N</I>,<I>N</I>-Diborylamines have emerged as promising reagents in organic synthesis; however, their efficient preparation and full synthetic utility have yet to be realized. To address both shortcomings, an effective catalyst for nitrile dihydroboration was sought. Heating CoCl<SUB>2</SUB> in the presence of <SUP>PyEt</SUP>PDI afforded the six-coordinate Co(II) salt, [(<SUP>PyEt</SUP>PDI)CoCl][Cl]. Upon adding 2 equiv of NaEt<SUB>3</SUB>BH, hydride transfer to one chelate imine functionality was observed, resulting in the formation of (κ<SUP>4</SUP>-<I>N,N,N,N</I>-<SUP>PyEt</SUP>IP<SUP>CHMe</SUP>N<SUP>EtPy</SUP>)Co. Single-crystal X-ray diffraction and density functional theory calculations revealed that this compound possesses a low-spin Co(II) ground state featuring antiferromagnetic coupling to a singly reduced imino(pyridine) moiety. Importantly, (κ<SUP>4</SUP>-<I>N,N,N,N</I>-<SUP>PyEt</SUP>IP<SUP>CHMe</SUP>N<SUP>EtPy</SUP>)Co was found to catalyze the dihydroboration of nitriles using HBPin with turnover frequencies of up to 380 h<SUP>-1</SUP> at ambient temperature. Stoichiometric addition experiments revealed that HBPin adds across the Co-N<SUB>amide</SUB> bond to generate a hydride intermediate that can react with additional HBPin or nitriles. Computational evaluation of the reaction coordinate revealed that the B-H addition and nitrile insertion steps occur on the antiferromagnetically coupled triplet spin manifold. Interestingly, formation of the borylimine intermediate was found to occur following BPin transfer from the borylated chelate arm to regenerate (κ<SUP>4</SUP>-<I>N,N,N,N</I>-<SUP>PyEt</SUP>IP<SUP>CHMe</SUP>N<SUP>EtPy</SUP>)Co. Borylimine reduction is in turn facile and follows the same ligand-assisted borylation pathway. The independent hydroboration of alkyl and aryl imines was also demonstrated at 25 °C. With a series of <I>N</I>,<I>N</I>-diborylamines in hand, their addition to carboxylic acids allowed for the direct synthesis of amides at 120 °C, without the need for an exogenous coupling reagent.</P> [FIG OMISSION]</BR>