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In this work, we report the caloric effect for an electronic system of the antidot type, modeled by combining a repulsive and attractive potential (parabolic confinement). In this system, we consider the action of a perpendicular external magnetic field and the possibility of having an Aharonov-Bohm flux (AB-flux) generated by a current passing through a solenoid placed inside the forbidden zone for the electron. The energy levels are obtained analytically, and the model is known as the Bogachek and Landman model. We propose to control the caloric response of the system by varying only the AB-flux, finding that, in the absence of an external magnetic field, the maximization of the effect always occurs at the same AB-flux intensity, independently of the temperature, while fixing the external magnetic field at a non-zero value breaks this symmetry and changes the point where the caloric phenomenon is maximized and is different depending on the temperature to which the process is carried. Our calculations indicate that using an effective electron mass of GaAs heterostructures and a trap intensity of the order of 2.896 meV, the modification of the AB-flux achieves a variation in temperature of the order of 1 K. Our analysis suggests that increasing the parabolic confinement twofold increases the effect threefold, while increasing the antidot size generates the reverse effect, i.e., a strong decrease in the caloric phenomenon under study. Due to the great diversity in technological applications that have antidots in electronics, the possibility of controlling their thermal response simply by varying the intensity of the internal current inside the solenoid (i.e., the intensity of AB-flux) can be a platform of interest for experimental studies.

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Consumption of St. John's wort plant is high worldwide due to its various medicinal properties. However, herbal products containing St. John's wort may be contaminated with toxic metals. This is often related to contamination of both water and the atmosphere, lack of proper cultivation methods, and inadequate plant storage conditions, as well as a lack of stricter sanitary supervision. A safety assessment of copper (Cu), lead (Pb), cadmium (Cd) and arsenic (As) content in 23 products containing St. John's wort (pharmaceutical herbal products, food supplements and traditional herbal remedies) sold in the metropolitan area of Mexico City was conducted. The analysis of metals was determined using a graphite-furnace atomic absorption spectrometer. All herbal products were contaminated with Cu, Pb, Cd and As. The pharmaceutical herbal items showed less contamination by metals. The daily human intake (DHI) values for Pb exceeded the permissible limits in the group of traditional herbal remedies. The DHI calculation for As exceeded the permitted intake values for all items in the group of traditional herbal remedies, five food supplements and one pharmaceutical herbal product. The hazard indicator calculation of the non-carcinogenic cumulative risk values for traditional herbal remedies was greater than 1, suggesting a risk to human health.

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A new Oligochaete worm genus with a single species is described from tropical rain forests of Southern Mexico. Lacandodrilus paludosus Fragoso & Rojas gen. et sp. nov., found in sandy and acid poor swampy soils, presented a characteristic morphology of semiaquatic oligochaetes. The new taxon is holandric, with male pores and ovaries in segment 13, with genital prostatic- like lobular glands in segments 13 and 14 and with long seminal vesicles contained within ovisacs. It is also characterized by exonephric holonephridia covered by a peritoneal granular layer, septal glands and long vascular commissures in former segments. It presents a pair of spermathecae without diverticula in segment 10 and it lacks gizzards, typhlosole or esophagus glands. The new taxon is tentatively placed in family Alluroididae, waiting for additional histological studies that will clarify some characters.

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Introducción: Durante las últimas décadas se ha estudiado la señal del electroencefalograma desde una perspectiva de matemática no-lineal. Esto permite entender la actividad eléctrica cerebral como un sistema dinámico complejo. Objetivo: Evaluar los exponentes de Hurst y sus correlaciones en la onda gamma durante una tarea de atención alternante e inhibición de la interferencia en estudiantes universitarios. Métodos: La muestra se constituyó por 14 alumnos de educación física. Para evaluar la actividad eléctrica cerebral se utilizó el dispositivo cerebro-interfaz Emotiv Epoc®. La atención alternante se estimó con el test de símbolos y dígitos, mientras que para la inhibición de la interferencia se empleó la prueba de palabras y colores de Stroop. Resultados: En la prueba de atención alternante, cuatro individuos revelaron mayor propensión al caos en el hemisferio derecho, uno presentó más tendencia en el hemisferio izquierdo y dos no tuvieron una predisposición definida. Por otra parte, durante la prueba de inhibición de la interferencia, cinco presentaron variaciones de las medias de Hurst entre las tres láminas del efecto Stroop, sobre todo de la región temporal. Los exponentes Hurst en ambas pruebas fueron inferiores a 0,5. Conclusiones: Durante la prueba de atención se observó un mayor caos de la actividad eléctrica cerebral, sin existir correlaciones entre las regiones estudiadas. Durante la prueba de inhibición las modificaciones de los exponentes de Hurst no presentaron patrones definidos hacia el orden o caos(AU)

Introduction: During the last decades the electroencephalogram signal has been studied from a nonlinear mathematical perspective. This allows understanding brain electrical activity as a complex dynamical system. Objective: To evaluate Hurst exponents and their correlations in the gamma wave during an alternating attention and interference inhibition task in university students. Methods: The sample consisted of 14 physical education students. The Emotiv Epoc® brain-interface device was used to evaluate brain electrical activity. Alternating attention was estimated with the symbols and digits test, while the Stroop words and colors test was used for interference inhibition. Results: In the alternating attention test, four individuals revealed a greater propensity to chaos in the right hemisphere, one showed a greater tendency in the left hemisphere and two had no defined predisposition. On the other hand, during interference inhibition, variations of Hurst average values between the three Stroop effect slices were determined in five subjects, especially in the temporal region. Hurst exponents in both tests were found to be less than 0.5. Conclusions: During the attention test, a greater chaos of brain electrical activity is observed, with no correlations between the regions studied. During the inhibition test, the modifications of the Hurst exponents do not present defined patterns towards order or chaos(AU)

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Increased life expectancy and high costs of medicines and medical care have led to the use of herbal products. However, these items may contain toxic compounds that have an impact on public health. We will focus on the regulatory aspects and differences of these products marketed in the North American region (USA-Mexico-Canada) from government websites and selected literature. Mexico has an ancestral tradition of using plants for the treatment, improvement, and maintenance of human health as compared with Canada and the USA Currently, the use of herbal products in this region has a regulatory framework. The legal framework in these three countries is related to their history, idiosyncrasies, socio-economic and cultural aspects. Therefore, there are different public policies for herbal products consumed in the region. Mexico has a more specific classification of these products. In Canada, all herbal products are classified as natural health products and the safety and efficacy must be scientifically proven. In the USA, the development of botanical drugs is very recent. In particular, both herbal products classified as food supplements in Mexico and dietary supplements in the USA may have risks in both safety and efficacy.

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The Bolivian Chaco is a semiarid region with a low population density, situated in the southeast part of the Plurinational State of Bolivia. Here, despite the improvements of the last 15 years, poverty remains high in rural areas, where social vulnerability is widespread. The Guaraní ethnic group often lives in isolated communities with a low standard of hygiene and sanitation. This epidemiological scenario favors the spread of transmissible diseases, including several parasitic infections belonging to the neglected tropical diseases (NTDs) group. In this area, a long-standing research activity, built upon the synergism between local and foreign institutions, has been established since the late 1980s and helps to fill in the knowledge gap about the epidemiology dynamics of soil-transmitted helminths, vector-borne parasites, and other parasitic diseases. A 35-year history of cooperation programs in parasitology research has contributed to informing local health authorities of the NTD burden in the Bolivian Chaco and, ultimately, supports local healthcare providers in the management of parasitic diseases.

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Introducción: en 2020, la rápida evolución de la pandemia por SARS-CoV-2 desencadenó una emergencia sanitaria que generó una importante reorganización del sistema de salud, lo que llevó a la discontinuación y posterior adecuación de los sistemas de formación. El objetivo de este estudio fue describir el impacto de la pandemia en un grupo de reumatólogos en formación en la Ciudad Autónoma de Buenos Aires. Materiales y métodos: se envió una encuesta online por correo electrónico a los alumnos de la Carrera de Especialista en Reumatología de la Sociedad Argentina de Reumatología y de la Universidad de Buenos Aires. Incluyó 24 preguntas relacionadas con el impacto de la pandemia en diferentes aspectos de la formación y las nuevas estrategias educativas implementadas. Resultados: de 114 alumnos contactados, respondieron 79 (69,3%). Aproximadamente el 90% indicó que su formación se afectó. Un 46% consideró que la práctica médica y la actividad académica se comprometieron por igual y el 45% solo la práctica médica. Un 50% realizó tareas no relacionadas con su formación. El 57% suspendió temporalmente la asistencia a su centro. También informaron una reducción del 55% (DE 18,6) de las actividades relacionadas con la consulta. Conclusiones: la pandemia por SARS-CoV-2 afectó a los estudiantes de Reumatología al limitar sus actividades prácticas y académicas, y por deber realizar tareas ajenas a su formación en más de la mitad de los casos.

Introduction: in 2020, the rapid evolution of the SARS-CoV-2 pandemic triggered a health emergency, generating an important heath system reorganization which led to the discontinuation and subsequent adaptation of training systems. The objective was to describe the pandemic impact on a group of rheumatology trainees in Buenos Aires, Argentina. Materials and methods: an online survey was sent through e-mail to rheumatology specialist course trainees of Argentine Society of Rheumatology and University of Buenos Aires. It included 24 close-ended questions about the pandemic impact on different aspects of rheumatology training and the new implemented educational response strategies. Results: from 114 trainees contacted, 79 (69.3%) responded. Approximately 90% indicated that their rheumatology training was affected. Forty-six percent thought that medical practice and academic activity were equally affected and 45% that only medical practice was compromised. About 50% reported that they had to perform tasks unrelated to their training. Fifty-seven percent discontinued temporarily the training site attendance. Participants reported a mean reduction of 55% (SD 18.6) of activities related to patient care. Conclusions: the SARS-CoV-2 pandemic affected rheumatology trainees, by limiting their practical and academics activities, and having to perform tasks unrelated to their training in more than a half.

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Los carcinomas uroteliales son el 4to tumor más común. Pueden ubicarse en el tracto urinario inferior (vejiga y uretra) o en el tracto urinario superior (cavidades renales, pelvis renal y uréter). Presentamos una serie de 3 casos, con cuadro de hematuria macroscópica, documentando tumores uroteliales, realizándose en estos casos un abordaje lumboscópico de riñón y una resección endoscópica del rodete vesical. Se realiza nefroureterectomía lumboscópica con resección de rodete vesical endoscópica transuretral. Los 3 pacientes fueron egresados al segundo día posquirúrgico sin complicaciones y en los tres casos el rodete vesical sin evidencia de actividad tumoral, y actualmente en vigilancia con excelente resultados oncológicos. La nefroureterectomía lumboscópica con resección endoscópica del rodete vesical es una técnica reproducible en manos experimentadas, con iguales resultados oncológicos que el abordaje abierto.

Urothelial carcinomas are the 4th most common tumor. They can be located in the lower urinary tract (bladder and urethra) or in the upper urinary tract (renal cavities, renal pelvis, and ureter). We present a series of 3 cases, with a picture of macroscopic hematuria, documenting urothelial tumors, performing in these cases a lumboscopic approach to the kidney and an endoscopic resection of the bladder rim. Lumboscopic nephroureterectomy was performed with transurethral endoscopic bladder rump resection. The 3 patients were discharged on the second postoperative day without complications and in the three cases the bladder rim without evidence of tumor activity, and currently under surveillance with excellent oncological results. Lumboscopic nephroureterectomy with endoscopic resection of the bladder rim is a reproducible technique in experienced hands, with the same oncological results as the open approach.

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Major depressive disorder (MDD) is a major health problem in Parkinson's disease (PD) patients. We described the clinical and sociodemographic factors of MDD among patients with PD at a national neurological referral center in Mexico. One hundred patients with PD + MDD were included in the study. All the patients were evaluated during the "ON" treatment phase of PD. Clinical scales for cognition (MMSE and MoCA) and MDD (MADRS) were applied. The mean age was 58.49 ± 11.02 years, and 57% of the sample was male. The most frequent symptom of PD was tremor (67%), and onset was more frequent on the right side (57%). Additionally, 49% of the patients with PD had moderate to severe (M/S) MDD. Selective serotonin reuptake inhibitors were the most frequent antidepressant treatment (69%). The scores of the scales were MADRS 21.33 ± 5.49, MoCA 21.06 ± 4.65, and MMSE 26.67 ± 1.20. The females had lower MMSE scores compared to the males (p = 0.043). The patients with M/S MDD had more rigidity at the beginning of PD (p = 0.005), fewer march alterations (p = 0.023), and a greater prevalence of left-side initial disease (p = 0.037). Rigidity was associated with M/S MDD (OR 3.75 p = 0.013). MDD was slightly more frequent in the males than in the females. The MDD symptoms and cognitive impairment were worse in the female population.

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Resumen El manejo quirúrgico de los tumores renales pequeños es la cirugía conservadora de nefronas, este tipo de manejo se reservaba para pacientes seleccionados, con riñón solitario, enfermedad renal crónica o tumores bilaterales. La evidencia sugiere que la nefrectomía parcial laparoscópica es equivalente en términos de resultados oncológicos y superior en las mediciones de calidad de vida comparada al abordaje abierto. Objetivos: determinar los resultados oncológicos en cuanto a bordes libres del tumor y complicaciones quirúrgicas en pacientes sometidos a nefrectomía parcial y enucleación de tumor renal laparoscópico "Zero isquemia". Metodología: estudio retrospectivo, observacional, y comparativo, universo pacientes de la Clínica privada Los Ángeles y de la Caja Nacional de Salud, Hospital Obrero Nº2, Cochabamba, Bolivia, que fueron sometidos a nefrectomía parcial laparoscópica, se agruparon en dos grupos: Grupo I: nefrectomía parcial y Grupo II: enucleación, se analizaron: tamaño y localización del tumor, RENAL score, tiempo quirúrgico, sangrado, días de estancia, complicaciones y reporte histopatológico. Se utilizó el SPSS versión 20 (IBM, Chicago, IL). Resultados: se evaluaron 17 pacientes, 3 fueron excluidos por terminar en cirugía radical, 6 parciales (Grupo I) y 8 enucleaciones (Grupo II). Edad promedio de 45,7 (± 8,6) vs 51,2 (± 6,3) años. Tamaño del tumor 7,8 (2,5-10) vs 3,2 (1-5,7) cm, El RENAL score en global de todos los pacientes fue de baja a moderada, se realizó un análisis por separado, en el grupo I, la distribución fue complejidad baja n=2 (33,3%), moderada n= 1 (16,7%) y alta n= 3 (50%), en el grupo II, baja complejidad n=5 (62,5%), moderada n=2 (25%), alta complejidad n= 1 (12,5%). Hubo diferencias a favor del grupo II (enucleación) en cuanto a tiempo quirúrgico y sangrado transoperatorio, presentando solo 1 caso con fuga urinaria, resuelta con colocación de catéter JJ, se evidencia iguales tiempos de estancia intrahospitalaria, en cuanto a los bordes quirúrgicos, se tuvo 2 (14,2%) casos con bordes positivos 1 para cada abordaje, los cuales se mantienen en vigilancia estrecha. Conclusiones: el abordaje laparoscópico es una opción equiparable al abierto, se obtuvieron iguales resultados en cuanto a control oncológico en relación a bordes libres y con menos complicaciones, aunque se requiere experiencia en cirugía laparoscópica y aumentar el seguimiento en tiempo y mayor número de casos.

Abstract Surgical management of small renal tumors involves nephron-sparing surgery, which used to be reserved for selected patients with a solitary kidney, chronic kidney disease or bilateral tumors. Evidence suggests that laparoscopic partial nephrectomy is equivalent to the open approach in terms of oncologic outcomes and superior in quality of life measures. Objectives: to determine oncologic outcomes regarding tumor free edges and surgical complications in patients undergoing laparoscopic "Zero ischemia" partial nephrectomy and enucleation of renal tumor. Methodology: retrospective, observational, and comparative study, with a universe of patients from Los Angeles private clinic and Caja Nacional de Salud, Hospital Obrero Nº2, Cochabamba, Bolivia, who underwent laparoscopic partial nephrectomy, were grouped in two groups: Group I: partial nephrectomy and Group II: enucleation. The following were analyzed: tumor size and location, RENAL score, surgical time, bleeding, days of stay, complications and histopathological report. SPSS version 20 (IBM, Chicago, IL) was used for statistical analysis. Results: seventeen patients were evaluated, 3 were excluded due to completion of radical surgery, 6 partial nephrectomies (Group I) and 8 enucleations (Group II). Mean age 45.7 (± 8.6) vs 51.2 (± 6.3) years. Tumor size 7.8 (2.5-10) vs 3.2 (1-5.7) cm, The overall RENAL score of all patients was low to moderate, a separate analysis was performed, in group I, the distribution was low complexity 2 (33.3%), moderate n=1 (16.7%) and high n=3 (50%), in group II, low complexity n=5 (62.5%), moderate n=2 (25%), high complexity n=1 (12.5%). There were differences in favor of group II (enucleation) in terms of surgical time and transoperative bleeding, presenting only 1 case with urinary leakage, resolved with placement of a JJ catheter. In terms of surgical edges, there were 2 (14.2%) cases with positive edges, 1 for each approach, which are kept under close surveillance. Conclusions: laparoscopic approach is an option comparable to the open one, equal results were obtained with respect to oncologic control in relation to free edges and with fewer complications, although experience in laparoscopic surgery is required, as well as an increase in follow-up time and a greater number of cases.