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This study introduces a novel volume coil design that features two slotted end-plates connected by six rungs, resembling the traditional birdcage coil. The end rings are equipped with six evenly distributed circular slots, inspired by Mansfield's cavity resonator theory, which suggests that circular slots can generate a baseline resonant frequency. One notable advantage of this proposed coil design is its reduced reliance on electronic components compared to other volume coils, making it more efficient. Additionally, the dimensions of the coil can be theoretically computed in advance, enhancing its practicality. To evaluate the performance and safety of the coil, electromagnetic field and specific absorption rate simulations were simulated using a cylindrical saline phantom and the finite element method. Furthermore, a transceiver coil prototype optimized for 7 Tesla and driven in quadrature was constructed, enabling whole-body imaging of rats. The resonant frequency of the coil prototype obtained through experimental measurements closely matched the theoretical frequency derived from Mansfield's theory. To validate the coil design, phantom images were acquired to demonstrate its viability and assess its performance. These images also served to validate the magnetic field simulations. The experimental results aligned well with the simulation findings, confirming the reliability of the proposed coil design. Importantly, the prototype coil showcased significant improvements over a similarly-sized birdcage coil, indicating its potential for enhanced performance. The noise figure was lower in the prototype versus the birdcage coil (NFbirdcage-NFslotcage= 0.7). Phantom image data were also used to compute the image SNR, giving SNRslotcage/SNRbirdcage= 34.36/24.34. By proving the feasibility of the coil design through successful rat whole-body imaging, the study provides evidence supporting its potential as a viable option for high-field MRI applications on rodents.

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Background: Assisted reproduction techniques in birds have contributed to many species' conservation and sustainable use. One of these techniques is semen cryopreservation, which is possible following the discovery of suitable cryoprotectants. Aims: This study aimed to characterize the fresh and post-thaw ejaculates of different species of birds of prey. Methods: The following species were included in the study: red-tailed hawk (Buteo jamaicensis) n=3, golden eagle (Aquila chrysaetos) n=3, and Harris's hawk (Parabuteo unicinctus) n=3. Twenty-five ejaculates were obtained for each species. The percentage of spermatozoa motility, viability, and morphology were evaluated. Results: Evident differences were observed among the ejaculates of the three species, particularly in sperm length and between the fresh and post-thaw parameters of the same species in which the motility reduced to approximately 40% after thawing. It was demonstrated that sperm cryopreservation of the studied species was possible using the same freezing protocol. Conclusion: This study showed that sperm characteristics could influence the parameters obtained during their in vitro conservation, both in the fresh and post-thaw states.

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Purpose: This case report aims to present a rare instance of conjunctival melanoma in a 5-year-old patient and contribute to the limited body of knowledge on pediatric conjunctival melanoma. The purpose is to understand the characteristics, diagnosis, and management of this uncommon malignancy in young individuals. Observations: The case describes a 5-year-old female with a progressively growing pigmented conjunctival lesion. The lesion was observed to be located on the temporal conjunctiva of the right eye and displayed distinctive features, including feeder vessels. Imaging revealed specific dimensions of the lesion and ruled out deeper invasions. Histopathological examination revealed architectural and cytologic atypia, positive immunohistochemical staining for HMB-45, and a Ki67 proliferation index of 20 %, confirming the diagnosis of conjunctival melanoma. Conclusions: Conjunctival melanoma, an uncommon malignancy even more so in pediatric patients, typically presents with pigmented growths and feeder vessels. This case underscores the need for thorough diagnosis and early intervention, as conjunctival melanoma can lead to devastating outcomes. The rarity of such cases limits our understanding of their etiology and progression. This case contributes to the literature on pediatric conjunctival melanoma and reinforces the importance of vigilance in detecting and managing ocular pigmented lesions in children.

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Hoy en día es común recibir pacientes en la clínica odontológica relatando dolor uni o bilateral en la zona lateral de la cara, más específicamente en la zona de las ramas mandibulares. Este dolor puede ser muchas veces de origen dental, muscular masticatorio, de las articulaciones temporomandibulares, o incluso tonsilar. Debido a que las anteriores son patologías más frecuentes, muchas veces el clínico no considera que la causa de estos dolores podría estar asociada al síndrome de Eagle. Esta investigación se fundamentó en la necesidad de utilizar las radiografías panorámicas como herramienta para asociar dolores que no remiten a tratamientos convencionales a calcificaciones del complejo estilohioideo, muchas veces hallazgos radiográficos que no son comúnmente tomados en consideración por el clínico. El objetivo del estudio fue eterminar la asociación entre calcificaciones del complejo estilohioideo en radiografías panorámicas y sintomatología clínica dolorosa en pacientes del centro de salud de la Universidad San Sebastián, sede Santiago, Chile. Se realizó un estudio correlacional, analítico y retrospectivo en el Centro de Salud de la Universidad San Sebastián. Se tomó una muestra aleatoria de 815 radiografías y fichas clínicas asociadas, en las cuáles se analizó la presencia, tipo y ubicación de calcificaciones del complejo estilohioideo, así como, si los pacientes relataron sintomatología dolorosa asociable al Síndrome de Eagle. Posteriormente se realizó un análisis descriptivo, exploratorio e inferencial de asociación entre variables. El porcentaje de pacientes que presentó calcificaciones del complejo estilohioideo alcanzó un 85,4%, siendo la mayoría de tipo elongado (70,98%), seguida del tipo segmentado (26,72%) y muy por debajo el tipo pseudoarticulado (2,3%). Con respecto a la prevalencia de sintomatología la gran mayoría de los pacientes no presentó (96,32%), sin verse diferencias según sexo o edad. Por último, al realizar el análisis de asociación el valor de X 2 calculado fue de 3,171, menor al valor de X2 crítico tabulado de 3,841. Al obtener un X2 calculado menor a un X2 crítico tabulado se demostró que no existe una asociación entre la presencia de calcificaciones del complejo estilohioideo y sintomatología clínica asociada. Además, las prevalencias de calcificaciones y sus tipos no variaron según la edad o género, lo que no nos permitió establecer una relación causal entre las variables.

Nowadays it is very common to receive patients in the dental clinic reporting unilateral or bilateral pain in the lateral area of the face, more specifically in the mandibular rami area. The origin of this pain can often be dental, muscular, from the temporomandibular joint or even tonsillar. Because the named pathologies are more frequent, many times the clinician does not consider that the cause of this pain could be associated with Eagle syndrome. This research was based on the need to use panoramic radiographs as a tool to associate pain that does not refer to conventional treatments with calcifications of the stylohyoid complex, many times radiographic findings that are not commonly considered by the clinician. This correlational cross analytical study was carried out at San Sebastián University Health Center. A random sample of 815 radiographs and associated clinical records was taken, in which the presence, type and location of calcifications of the stylohyoid complex were analyzed, as well as whether the patients reported painful symptoms associated with Eagle syndrome. Subsequently, a descriptive, exploratory, and inferential analysis of association between variables was conducted. The percentage of patients who presented calcifications of the stylohyoid complex reached 85.4%, being the majority the elongated type (70.98%), followed by the segmented type (26.72%) and far below the pseudoarticulated type (2.3%). Regarding the prevalence of symptoms, the vast majority of patients did not present (96.32%), without seeing differences according to gender or age. Finally, when performing the association analysis, the calculated X2 value was 3.171, lower than the critical tabulated X2 value of 3.841. Obtaining a calculated X2 lower than a critical tabulated X2 showed that there is no association between the presence of calcifications of the stylohyoid complex and associated clinical symptoms. In addition, the prevalence of calcifications and their types did not vary according to age or gender, which did not allow us to establish a causal relationship between the variables.

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Los tumores de la fosa isquiorrectal son poco frecuentes, habitualmente descritos en reportes o series de casos. Estas lesiones son un reto terapéutico, requiriendo un estudio preoperatorio apropiado, además de discusión y manejo guiado por un comité multidisciplinario, que permiten lograr resultados óptimos tanto oncológicos como funcionales. Presentamos un caso de un hombre de 73 años con antecedentes de resección de un tumor glúteo izquierdo en otro centro 5 años antes. La biopsia fue compatible con un sarcoma epiteloideo (SE) de alto grado, con margen quirúrgico < 0,5 mm que requirió ampliación de los márgenes posteriormente. Además, se realizó radioterapia adyuvante. Al cuarto año de seguimiento el paciente desarrolla dolor e induración con retracción en relación a cicatriz quirúrgica, siendo objetivada una recidiva tumoral local. Luego de una discusión multidisciplinaria, se realizó una desfuncionalización con ileostomía en asa laparoscópica y resección tumoral con preservación del ano y del piso pélvico. El defecto fue cubierto por el equipo de cirugía plástica utilizando un colgajo perforante de la arteria glútea superior. La biopsia confirmó la recidiva tumoral y los márgenes quirúrgicos fueron negativos. El paciente es dado de alta a los 25 días postoperatorios por cuidados del colgajo, sin complicaciones. Al año de seguimiento el paciente no presenta recidiva tumoral, la ileostomía fue cerrada, y sus resultados funcionales en términos defecatorios y de la herida son buenos.

Ischiorectal fossa tumors are rare lesions, mostly described in case reports or case series. These lesions represent a diagnostic and therapeutic challenge. Hence, an appropriate preoperative study and multidisciplinary discussion are essential to achieve good oncologic and functional results. We report a case of a 73-year-old male operated on five years before in another health center due to the diagnosis of a left gluteal tumor. The lesion was excised, and biopsies confirmed a high-grade epithelioid sarcoma with a close margin, requiring a subsequent wider excision of the surgical margins. The patient received adjuvant radiotherapy. After four years of follow-up, the patient developed mild pain with skin retraction around the former incision. A local recurrence was diagnosed by imaging. In a multidisciplinary team meeting, a decision to resect the lesion with preservation of the anus and the pelvic floor was taken. The patient underwent a laparoscopic defunctioning loop ileostomy and a resection of the recurrent tumor in the ischiorectal fossa with preservation of the anal sphincter. The defect was covered utilizing a superior gluteal artery perforator flap and a partial gluteus maximus muscle rotation. The tumor was completely excised with negative margins. The patient was discharged without complications after 25 days due to flap management. After one year of follow-up, the patient is recurrence-free, and the ileostomy was closed.

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RESUMEN La anestesia aviar constituye un área de estudio controvertida debido a la morfofisiología diferente entre aves y mamíferos. Lo anterior hace necesario desarrollar protocolos confiables que contribuyan al bienestar de las aves en cautiverio. La anestesiología en aves representa una actividad clínica que demanda especial cuidado de los pacientes que requieren procedimientos quirúrgicos. Este estudio describe los parámetros de SpO2, frecuencias cardiaca y respiratoria durante la anestesia con isoflurano de Melopsittacus undulatus. Se monitorearon 12 machos y 7 hembras durante las etapas anestésicas. La inducción anestésica duró 1:30 ± 0:31 min en machos y 2:19 ± 0:16 min en hembras, con promedio de mantenimiento de 7:00 ± 1:39 min. No se encontraron diferencias significativas en los tiempos anestésicos entre hembras y machos (p>0,05). Se presentó una variación estadísticamente significativa (p<0,05) de la SpO2 en el periodo de recuperación, las hembras presentaron mayor saturación de oxígeno (71±4 %) en comparación con los machos (89±2 %). En la valoración de la función cardiaca durante la anestesia, no se detectaron diferencias significativas entre machos y hembras (p>0,05). Se concluye como un protocolo anestésico seguro para procedimientos clínicos de corta duración para aves pequeñas como M. undulatus.

ABSTRACT Avian anesthesia is a controversial area of study due to the differences between birds and mammals morpho physiology. This makes necessary to develop reliable protocols for birds in captivity, which contributes to their welfare under human care. Bird anesthesiology today represents a veterinary clinical activity that demands special care for patients requiring surgical procedures. This study describes the parameters of SpO2, cardiac activity, heart and respiratory rate during anesthesia with isoflurane for Melopsittacus undulatus. 12 males and 7 females were monitored during the anesthetic stages. Anesthetic induction lasted 1:30 ± 0:31 min in males and 2:19 ± 0:16 min in females, with an average maintenance time of 7:00 ± 1:39 min. No significant differences were found in anesthetic times between females and males (p>0.05). There was a statistically significant variation (p<0.05) of SpO2 in the recovery period, females had higher oxygen saturation (71±4%) compared to males (89±2%). In the assessment of cardiac function during anesthesia, no significant differences were detected between males and females (p>0.05). It is concluded as a safe anesthetic protocol for clinical procedures of short duration for small birds such as M. undulates.

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Hypoplastic left heart syndrome (HLHS) is a congenital heart disease of low prevalence and high lethality. OBJECTIVE: to determine the perinatal outcome and survival at one and five years of fetuses with a prenatal diagnosis of HLHS. PATIENTS AND METHOD: Prospective cohort study of all the fetuses with HLHS from the Perinatal Reference Center (CERPO) born between January 2008 and December 2017. Demographic and clinical perinatal data were obtained from the CERPO database. At one and five years of age, a telephone survey was conducted to determine the surgical treatment and survival. RESULTS: 1,573 patients were admitted to the CERPO, 899 with congenital heart diseases (CHD), confirming the prenatal diagnosis of HLHS in 7% (110/1,573). The mean gestational age at diagnosis and the median at admission were 26+3 and 32+3 weeks, respectively. 89% were born alive, 90% at term, and 57% delivered by cesarean section. The median birth weight was 3,128 grams. 89% survive the prenatal period, 50% the early neonatal period, 33% the late neonatal period, 19% the first year, and 17% at 5 years. CONCLUSIONS: In this center, the one-year and five-year survival of fetuses with prenatal diagnosis of HLHS was 19% and 17%, respectively. It is important for prenatal counseling to consider publications based on local casuistry, that include patients with prenatal and postnatal diagnoses and those who underwent surgery, in order to provide more precise information to parents.

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INTRODUCCIÓN: La infección por hantavirus es endémica en América del Sur, con un amplio espectro de gravedad y una letalidad que varía entre 17 y 40 por ciento. El presente estudio recoge información de 25 años de vigilancia epidemiológica en Buenos Aires, Argentina. OBJETIVO: Caracterizar el comportamiento de la serie temporal 1997-2021, observando tendencia y estacionalidad. MÉTODOS: La función de serie temporal utilizada empleó la media móvil centrada según periodos trimestrales, de forma que cada año se dividió en cuartiles. Se consideró un modelo multiplicativo. RESULTADOS: Con una tasa de mortalidad de la serie de 0,15 por 100 mil y de letalidad de 22,6, la razón varones : mujeres fue de 3,4:1. La distribución sindrómica mostró mayor compromiso renal, siendo la tasa de mortalidad prácticamente igual en ambos sexos. CONCLUSIÓN: Como enfermedad infecciosa, la infección por hantavirus reflejó en los últimos 25 años un comportamiento, recurrente y estacional, endémico y compartido en sus características clínicas con el resto de la región andina.

BACKGROUND: Hantavirus infection is endemic in South America, with a wide spectrum of severity and a fatality rate that varies between 17-40 percent. This study collects information from 25 years of epidemiological surveillance in Buenos Aires, Argentina. AIM: To characterize the behavior of the 1997-2021 time series, observing trends and seasonality. METHODS: The time series function used the moving average centered according to quarterly periods, so that each year was divided into quartiles. A multiplicative model is missed. RESULTS: With a mortality rate for the series of 0.15 per 100,000 and a fatality rate of 22.6, the male : female ratio was 3.4:1. The syndromic distribution showed greater renal involvement, with the mortality rate being practically the same in both sexes. CONCLUSION: As an infectious disease, hantavirus has reflected in the last 25 years a behavior, recurrent and seasonal, endemic and shared in its clinical characteristics with the rest of the Andean region.

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Soil is the base of any ecosystem since it conserves nutrients and water for plant roots including agriculture and plantations. In dry and semi-arid places across the world, including the UAE, sandy soils are common. Their fertility is extremely low, and production is hampered by a number of agronomic challenges. Soil conditioner sources like bentonite and chicken manure might be used to improve the poor sandy soil attributes and hence boost soil productivity. From November 2019 to March 2020, an experiment was conducted to investigate the growth rates of Bougainvillea following bentonite and chicken manure amendments to sandy soil taken from Lehbab, Dubai. Bougainvillea was evaluated for its plant height (cm), max length of primary branch (cm), the number of leaves per plant, number of secondary branches, shoot weight (g), root length (cm), root weight (g), root/shoot ratio, chlorophyll contents, and chlorophyll a* and b*. In this experiment, a complete randomized design (CRD) with five treatments was used (10 replications per treatment). According to the findings, bentonite and chicken manure additions considerably influence the productive properties of sandy soil, as indicated by Bougainvillea growth. Additionally, the research suggests that Bougainvillea may be efficiently planted with 10% bentonite and 15% chicken manure applied to sandy soil, resulting in the healthiest plants compared to other amendments.

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AIMS: Cervical cancer incidence and mortality rates are approximately 55% higher in the Rio Grande Valley (RGV) along the Texas-Mexico border compared with the average rates in the US. Our aim was to improve cervical cancer prevention efforts in the RGV through a comprehensive multilevel intervention initiative focused on community education, patient navigation, and training of local providers. METHODS: We initiated a program in the RGV which consisted of (1) community education, (2) patient navigation, and (3) a training/mentoring program for local medical providers including hands-on training courses coupled with telementoring using Project ECHO® (Extension for Community Health Outcomes). We assessed the number of women undergoing cervical cancer screening, diagnosis, and treatment at three participating clinics caring for underserved women in the region. RESULTS: From November 2014 to October 2018, 14,846 women underwent cervical cancer screening. A total of 2030 (13.7%) women underwent colposcopy for abnormal results (179% increase over baseline) and 453 women underwent loop electrosurgical excision procedures (LEEPs) for treatment of cervical dysplasia. Invasive cancer was diagnosed in 39 women who were navigated to a gynecologic oncologist for treatment. Seven local medical providers were trained to perform colposcopy and/or LEEP. Project ECHO telementoring videoconferences were held every 2 weeks for a total 101 sessions with an average of 22 participants per session and a total of 180 patient cases presented and discussed. CONCLUSIONS: Our program led to a large number of women undergoing diagnosis and treatment of cervical dysplasia in the RGV. If sustained, we anticipate these efforts will decrease cervical cancer rates in the region. The program is currently being expanded to additional underserved areas of Texas and globally to low- and middle-income countries.

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RESUMEN Este reporte de caso describe la reparación quirúrgica de una ruptura traumática total de uretra membranosa de un paciente macho canino de cinco años, raza mestiza, que fue atropellado tres días atrás por un automóvil. En este procedimiento se usó la técnica descrita por Fossum (2019) con modificaciones realizadas por la experiencia quirúrgica de los autores: se utilizó un punto de fijación prostático que permitió disminuir las fuerzas de tensión ejercidas por la vejiga y el tamaño del defecto. En casos de trauma abdominal, la presencia de comorbilidades se asocia a peor pronóstico, en este caso, el uroabdomen que fue tratado de forma inmediata. El paciente permaneció en posoperatorio durante cuatro semanas y catorce meses después, presentó perfecto funcionamiento del tracto urinario inferior con flujo normal de orina, por lo que se considera que la técnica fue exitosa. Se administraron antibióticos sistémicos, antiinflamatorios y el cierre completo de la herida se dio tres semanas después. El objetivo de este trabajo es presentar una técnica quirúrgica poco invasiva y con escasas complicaciones intraoperatorias en la cual se modifica el procedimiento quirúrgico convencional, lo que genera un resultado exitoso sin que sea necesaria la realización de una osteotomía púbica, la cual, además de ser altamente invasiva con los tejidos, es bastante dolorosa para el paciente.

ABSTRACT This case report describes the surgical repair of a total traumatic rupture of the membranous urethra in a 5 years old, mixed-breed male canine patient who was hit three days earlier by a car. In this procedure, the technique described by Fossum (2019) was used with modifications made by the surgical experience of the authors, where a prostatic fixation point was used, allowing to reduce the tension forces exerted by the bladder and the size of the defect. In cases of abdominal trauma, comorbidities are associated with a worse prognosis, in this case, the uroabdomen was treated immediately. The patient remains in the postoperative period for 4 weeks and 14 months later presents a perfect function of the lower urinary tract with normal urine flow, considering that the technique was successful. Systemic antibiotics and anti-inflammatories were administered, and the wound was completely closed three weeks later. The objective of this work is to present a minimally invasive technique without intraoperative complications in which the conservative procedure is modified, generating a successful result without the need for a pubic osteotomy which, in addition to being highly invasive with the tissues, is quite painful for the patient.

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Ischiorectal fossa tumors are rare lesions, mostly described in case reports or case series. These lesions represent a diagnostic and therapeutic challenge. Hence, an appropriate preoperative study and multidisciplinary discussion are essential to achieve good oncologic and functional results. We report a case of a 73-year-old male operated on five years before in another health center due to the diagnosis of a left gluteal tumor. The lesion was excised, and biopsies confirmed a high-grade epithelioid sarcoma with a close margin, requiring a subsequent wider excision of the surgical margins. The patient received adjuvant radiotherapy. After four years of follow-up, the patient developed mild pain with skin retraction around the former incision. A local recurrence was diagnosed by imaging. In a multidisciplinary team meeting, a decision to resect the lesion with preservation of the anus and the pelvic floor was taken. The patient underwent a laparoscopic defunctioning loop ileostomy and a resection of the recurrent tumor in the ischiorectal fossa with preservation of the anal sphincter. The defect was covered utilizing a superior gluteal artery perforator flap and a partial gluteus maximus muscle rotation. The tumor was completely excised with negative margins. The patient was discharged without complications after 25 days due to flap management. After one year of follow-up, the patient is recurrence-free, and the ileostomy was closed.

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Introducción: La consulta nutricional es la primera línea de atención en niñas y niños en salud pública que presentan condiciones de malnutrición por déficit o exceso. Sin embargo, la atención a estos niños y niñas fue afectada por las movilizaciones sociales y la pandemia por COVID-19. Objetivo: Evaluar la tendencia de las consultas realizadas a menores de 9 años por profesional nutricionista en la región del Maule, Chile, desde el año 2017 a 2021. Métodos: Estudio descriptivo de corte longitudinal histórico basado en los datos de los Registros Estadísticos Mensuales (REM) del Servicio de Salud del Maule, las tendencias fueron analizadas con coeficiente de determinación (R2) mediante la regresión de Prais-Winsten. Resultados: Se analizaron 274.377 consultas nutricionales de niños/as menores de 9 años. 53,8% en clasificación de malnutrición por exceso y 12,1% en déficit. Se registró una disminución de 56,8% en las consultas nutricionales durante las movilizaciones sociales y un 92% al inicio de pandemia. Se observó una tendencia al aumento de las consultas por déficit nutricional, especialmente en menores de 12 meses (R2 0,633, β=4,45, p<0,001). Conclusión: La situación social y epidemiológica afectaron significativamente las atenciones nutricionales en salud pública. Es necesario dar una mayor visibilidad de los profesionales nutricionistas y promover el desarrollo de estrategias innovadoras para afrontar este escenario epidemiológico.

Background: The nutritional appointments is the first line of care for children with malnutrition or overweight in public primary health, but its normal functioning was affected by social mobilizations and the COVID-19 pandemic. Objective: To evaluate trends in consultations among children under 9 years of age in the Maule region, Chile, between 2017 and 2021. Methods: Descriptive longitudinal study based on data from the Monthly Statistical Records (REM) of the Maule Health Service, the trends were analyzed with coefficient of determination (R2) using Prais-Winsten regression. Results: 274,377 nutritional consultations were analyzed, of which 53.8% were overweight and 12.1% with malnutrition. A 56.8% decrease in nutritional consultations was recorded during social mobilizations and 92% at the beginning of the pandemic. A tendency to increase consultations due to malnutrition was observed, especially in children under 12 months of age (R2 0.633, β=4.45, p<0.001). Conclusion: The social and epidemiological situations significantly affected nutritional care in public health. It is necessary to give nutrition professionals greater visibility and promote the development of innovative strategies to deal with this epidemiological scenario.

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Biological nitrogen fixation (BNF) is a process through which a group of microorganisms called diazotrophs convert unassimilable atmospheric nitrogen into ammonia. In aqueous media, ammonia yields ammonium ions that can be assimilated by microorganisms and plants. To reduce the application of nitrogen fertilizers and their environmental effects, an alternative approach toward sustainable agriculture is the induction of artificial associations between diazotrophs and plants. This has led to increased interest in the search for microorganisms capable of supplying nitrogen to crops. This article presents a simple, economical, and sensitive spectrophotometric method for estimating the BNF capacity of bacteria cultured in a liquid NFb medium, based on the variation of absorbance caused by the change in color of bromothymol blue in the culture medium. The structure and color of this indicator are modified by pH shifts, which depend on the concentration of fixed ammonium ions.•The nitrogen concentration (estimated from the ammonium in the culture medium) showed a positive correlation (R 2 = 0.984) with the absorbance measured at 610 nm. The regression equation obtained through the origin was y = 0.009682140x, where y is the absorbance and x is the nitrogen concentration in the culture medium.•The methods used at present to measure the efficiency of BNF require expensive equipment, which may not be affordable for many laboratories or companies working in this field.•This technique can be used for pure bacterial strains and microbial consortia from soil or commercial products.

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The term postbiotics has acquired great interest in recent years. Numerous studies have shown a potential beneficial effect of its use in many inflammatory pathologies. However, it has not been much explored in ocular inflammatory diseases. The aims of this study were to develop and characterise an ophthalmic formulation with a postbiotic of Lactiplantibacillus plantarum CRL 759, and to evaluate its anti-inflammatory actions on murine macrophage stimulated with lipopolysaccharides (LPS) in vitro. First, we evaluated the ability of L. plantarum CRL 759 to generate a supernatant with anti-inflammatory property using different buffers. Then, we studied the stability at different temperatures and storage times of the generated postbiotic. In vitro assays showed that incubation of L. plantarum CRL 759 in modified phosphate buffer according to Sorensen (called POF-759), generated a supernatant that significantly reduced the production of interleukin-6, tumour necrosis factor-α, and nitric oxide by RAW 264.7 cells stimulated with LPS. Furthermore, POF-759 maintained its anti-inflammatory activity at room temperature, 4 and -20 °C, up to 30 days of storage. From the studies reported here, a postbiotic product with anti-inflammatory properties and optimal characteristics for the formulation of eye drops was obtained.

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There are minority and stigmatized groups who face particular challenges to their full participation in society. This study's objective was to conduct a systematic review to determine theoretical and methodological underpinnings in behavioral economics that explain how stigmatization emerges within the relationship processes and social structures of individuals. Data from 1940 to 2019 were sourced from 12 relevant electronic databases such as Scopus and Web of Science. Following PRISMA guidelines for systematic reviews, 26 studies out of 3459 met the inclusion criteria. Most of the studies applied experimental economics and were published between 2002 and 2018. Overall, the articles focus their research on the experiences of discrimination based on stereotypes and test their hypotheses through economic games. The data synthesis seems to reveal weak conceptual clarity, circular reasoning, and a hint of the problem of infinite regress. Thus, these issues open new and exciting avenues for future research to explore via an array of experimental applications.

Existen grupos minoritarios y estigmatizados que enfrentan retos particulares para lograr su completa participación en sociedad. El objetivo de este estudio fue conducir una revisión sistemática para determinar los cimientos teóricos y metodológicos en economía del comportamiento que explican cómo surge la estigmatización dentro de los procesos de relacionamiento y estructuras sociales de los individuos. Los datos abarcan el período de 1940 a 2019 y se obtuvieron de 12 bases de datos electrónicas relevantes, tales como Scopus y Web of Science. Siguiendo la guía de PRISMA para revisiones sistemáticas, 26 estudios de 3459 cumplieron con los criterios de inclusión. La mayoría de los estudios aplicó economía experimental y fueron publicados entre 2002 y 2018. En general, los artículos enfocan su investigación en experiencias de discriminación basadas en estereotipos y prueban sus hipótesis a través de juegos económicos. La síntesis de los datos parece revelar una débil claridad conceptual, razonamiento circular y un atisbo del problema de regresión infinita. Lo anterior abre nuevas y emocionantes vías de investigación futura para explorar a través de una variedad de aplicaciones experimentales.

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Ehrlichia canis has gained importance over the years as a zoonotic bacterium, nevertheless in Mexico is unknown the extent of the problem in animals and public health. The country had a few studies carried out locally using serology and molecular tests as diagnostic methods. Ehrlichiosis is not considered endemic in the central valley of Mexico, because the climatic conditions in the region have not allowed the vector (Rhipicephalus sanguineus) to establish itself adequately, therefore, diagnosis is not used in clinical practice in this area. A nested PCR (nPCR) offers rapid results with high sensitivity and specificity regardless of cost. The use of a recombinant positive control provides the advantage of timely diagnosis, follow-up treatment and allows the clinician to decide. In this work, the nPCR reported by Wen et al. (J Clin Microbiol 35(7):1852-2185, 1997) was used for the diagnosis of E. canis by modifying the reaction conditions to improve the detection of the test. We constructed a recombinant positive control to nPCR as diagnostic technique for E. canis, also we modified the reaction conditions to improve detection of the test which allowed the diagnosis of E. canis in dogs in the Mexican Republic using 53 samples from dogs with positive serological diagnosis of Ehrlichiosis, some of them from the valley of Mexico. Currently, this nPCR is offered to public at the Faculty of Veterinary Medicine and Zootechnics of the National Autonomous University of Mexico at an accessible cost and allows to begin to generate epidemiological information to know distribution of the bacterium.

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Hydrological and erosion dynamics are prone to change due to natural factors, human activities, or climate change. These changes are mainly related to modifications of land use and cover and can be assessed through the concept of connectivity, which analyzes how the spatial distribution of the elements facilitates runoff and sediment transport. The objective of this study was to evaluate changes in hydrological and sediment connectivity over 42 years and projected under a climate change scenario in the tropical Santa Cruz catchment in Aquismón, S.L.P., Mexico. The index of connectivity (IC) was computed using SedInConnect version 2.3 and the ArcSWAT model to estimate runoff. Hydrological connectivity and runoff were projected for 2027 using the MPI ECHAM 5 in the A2 climate change scenario. The results indicated that spatio-temporal changes in land use/cover, in conjunction with geomorphological features and expected climate change, would modify hydrological and sediment connectivity, especially in flat areas, where conversion of natural vegetation to cropland was steadily increasing over the years. Under future conditions, runoff and sediment transport are likely to increase, which will impact soil erosion and vulnerability to flooding but will not necessarily be negative. The study shows how spatial-temporal integration of runoff, sediments, landforms, land use cover and change, and connectivity can improve our understanding of catchment dynamics and the importance of analyses that characterize their evolution. The results can subsequently be applied and replicated in other catchments for management and restoration purposes.

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