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1.
Eur Rev Med Pharmacol Sci ; 28(8): 3275-3286, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38708486

RESUMEN

OBJECTIVE: This study aimed to compare two routes of administration and different dosages of streptozotocin (STZ) for the pharmacological induction of gestational diabetes mellitus (GDM) in pregnant CD1 females. MATERIALS AND METHODS: 35 female CD1 mice were divided into 5 groups (n = 7). Diabetes mellitus (DM) was induced with STZ by two routes and two doses: 1) Control Group without administration of STZ (CL), 2) Intraperitoneal Group with 200 mg of STZ/Kg of weight (IP200), 3) Intraperitoneal Group with 230 mg of STZ/Kg of weight (IP230), 4) Subcutaneous Group with 200 mg of STZ/Kg of weight (SC200) and 5) Subcutaneous Group with 230 mg of STZ/Kg of weight (SC230). Body weight, food and water intake, glycemia, Homeostatic Model Assessment of Insulin Resistance Index (HOMA-IR), survival, and birth rate were identified. RESULTS: The SC230 group turned out to be the most effective dose and route for the induction of GDM in pregnant females. This scheme managed to reproduce sustained hyperglycemia with high HOMA-IR, the presence of polyphagia, polydipsia, and weight loss. In addition, the birth rate and survival were high compared to the other doses and routes of administration. CONCLUSIONS: The administration of a single dose of 230 mg/kg of weight by subcutaneous route supposes advantages compared to previously used models since it decreases the physiological stress due to manipulation and the costs since it does not require repeated doses or adjuvants such as high lipid diets to potentiate the diabetogenic effect of STZ. Graphical Abstract: https://www.europeanreview.org/wp/wp-content/uploads/Graphical-abstract-12.jpg.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Gestacional , Estreptozocina , Animales , Femenino , Embarazo , Ratones , Diabetes Mellitus Experimental/inducido químicamente , Estreptozocina/administración & dosificación , Inyecciones Subcutáneas , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inyecciones Intraperitoneales , Resistencia a la Insulina , Peso Corporal/efectos de los fármacos
2.
Arch. Soc. Esp. Oftalmol ; 99(5): 209-212, May. 2024. mapas
Artículo en Español | IBECS | ID: ibc-VR-72

RESUMEN

La neuromiotonía ocular es una patología poco frecuente caracterizada por episodios recurrentes de diplopía binocular ocasionada por una contracción paroxística mantenida de uno o más músculos extraoculares inervados por un mismo nervio craneal, espontáneamente o inducidos por una versión concreta mantenida en el tiempo, normalmente relacionado con un antecedente de radioterapia local intracraneal. Presentamos el caso de una mujer de 46 años que presenta episodios de diplopía binocular recurrentes, diagnosticada de neuromiotonía ocular del VI nervio craneal izquierdo a los 8 años de padecer un cáncer de cavum tratado mediante radioterapia local y en completa remisión. Aunque es poco frecuente, la radiación a nivel de cavum debe tenerse en cuenta como potencial causa de neuromiotonía ocular, por su proximidad a la base del cráneo y su estrecha relación con el trayecto de los nervios oculomotores, especialmente el VI par craneal, como el caso que se presenta en este artículo.(AU)


Ocular neuromyotonia is an infrequent disorder characterised by recurrent episodes of binocular diplopia caused by paroxysmal contraction of one or several extraocular muscles innervated by the same cranial nerve. It can be triggered spontaneously or caused by prolonged contraction of specific eye muscle(s) and is usually related to a local intracranial radiotherapy antecedent. We report the case of a 46-year-old woman who developed intermittent episodes of binocular diplopia 8 years after radiotherapy for a nasopharyngeal carcinoma. After a complete neuro-ophthalmic assessment we diagnosed the case as an abducens nerve neuromyotonia. Although it is infrequent, radiotherapy to the nasopharynx is a possible cause of ocular neuromyotonia, due to the proximity to the base of the skull and extraocular motor nerve pathways, especially that of the VI cranial nerve, as is the case presented in this article, about a patient whose history is a nasopharyngeal carcinoma treated with local radiotherapy.(AU)


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Síndrome de Isaacs , Carcinoma Nasofaríngeo , Diplopía , Radioterapia , Visión Ocular , Oftalmología , Oftalmopatías , Pacientes Internos , Examen Físico
5.
Clin Transl Radiat Oncol ; 45: 100753, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38433951

RESUMEN

Background: Pancreatic Stereotactic Body Radiotherapy (SBRT) allows for the administration of a higher biologically effective doses (BED), that would be essential to achieve durable tumor control. Escalating treatment doses need a very accurate tumor positioning and motion control during radiotherapy.The aim of this study to assess the feasibility and safety of a Simultaneous Integrated Boost (SIB) dose-escalated protocol at 45 Gy, 50 Gy and 55 Gy in 5 consecutive daily fractions, in Border Line Resectable Pancreatic Cancer (BRCP) /Locally Advanced Pancreatic Cancer (LAPC) by means of a standard LINAC platform. Methods: Patients diagnosed of BRPC/LAPC, candidates for neoadjuvant chemotherapy and SBRT, in four university hospitals of the province of Las Palmas (Canary Islands, Spain) were included in this prospective study. Radiotherapy was administered using standard technology (LINACS) with advanced positioning (Lipiodol® and metallic stent used as fiducial markers) and tumor motion control (4D, DBH, Calypso®). There were 3 planned dose-escalated SIB groups, 45 Gy/5f (9 patients) 50 Gy/5f (9 + 9 patients) and 55 Gy/5f (9 patients). The defined primary end points of the study were the safety and feasibility of the proposed treatment protocol. Secondary endpoints included radiological tumor response after SBRT, local control and survival. Results: From June 2017 to December 2022, sixty-two patients were initially assessed for eligibility in the study in the four participating centers, and 49 were candidates for chemotherapy (CHT). Forty-one were referred to radiotherapy after CHT and 33 finally were treated by escalated-dose SIB, 45 Gy (9 patients) 50 Gy (16 patients), 55 Gy(8 patients). All patients completed the scheduled treatment and no acute or late severe (≥grade3) gastrointestinal toxicity was observed.Local response was analyzed by CT/MRI two months after the end of SBRT. Ten patients (31,25 %) achieved objective response (2/9:45 Gy, 5/15:50 Gy, 3/8:55 Gy). Follow-up was closed as July 2023. Freedom from local progression at 1-2y were 89,3% (95 %CI:83,4-95,2%) and 66 % (95 %CI:54,6-77,4%) respectively. The 1-2y survival rates were 95,7% (95 %CI:91,4-100 % and 48,6% (95 %CI:37,7-59,5%) respectively. Conclusion: These promising results should be confirmed by further studies with larger sample size and extended follow-up period.

8.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): 224-230, Mar. 2024. ilus, tab, graf
Artículo en Inglés | IBECS | ID: ibc-231390

RESUMEN

Background: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. Objective To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. Material & methods: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. Results: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. Conclusions: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future. (AU)


Antecedentes: La pandemia de COVID-19 ha podido afectar negativamente el diagnóstico precoz del cáncer de piel. Objetivo Comparar las características epidemiológicas, clínicas e histopatológicas en los pacientes intervenidos de carcinoma de células escamosas (CCE) cutáneo antes de la pandemia y después del inicio de la pandemia. Material y métodos: Se diseñó un estudio transversal que incluía 2 series de pacientes: 1) pacientes intervenidos de CCE el año posterior a la declaración del confinamiento general en España (15 de marzo de 2020), y 2) pacientes intervenidos de CCE el año previo. Se recogieron variables epidemiológicas, clínicas e histopatológicas, así como el estadio tumoral y el grado de riesgo. Resultados: Se incluyeron 248 pacientes (127 intervenidos antes de la pandemia y 121 intervenidos después de la pandemia). Tras el inicio de la pandemia, el porcentaje de CCE de alto riesgo aumentó significativamente de 32,3 a 45,5% (p=0,011). No obstante, no se encontraron diferencias significativas en el grosor tumoral, la invasión perineural o la presencia de metástasis. Conclusiones: Aunque no se produjo una reducción significativa en el número de CCE intervenidos después de la pandemia, ha habido un incremento significativo en los CCE de alto riesgo. Todo ello puede conllevar un incremento en la mortalidad por cáncer de piel en el futuro. (AU)


Asunto(s)
Humanos , Neoplasias Cutáneas , Detección Precoz del Cáncer , Carcinoma de Células Escamosas , Pacientes , Factores Epidemiológicos , Cirugía General , Grado de Riesgo , Estudios Transversales , España
9.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): t224-t230, Mar. 2024. ilus, tab, graf
Artículo en Español | IBECS | ID: ibc-231392

RESUMEN

Antecedentes: La pandemia de COVID-19ha podido afectar negativamente el diagnóstico precoz del cáncer de piel. Objetivo Comparar las características epidemiológicas, clínicas e histopatológicas en los pacientes intervenidos de carcinoma de células escamosas (CCE) cutáneo antes de la pandemia y después del inicio de la pandemia. Material y métodos: Se diseñó un estudio transversal que incluía 2 series de pacientes: 1) pacientes intervenidos de CCE el año posterior a la declaración del confinamiento general en España (15 de marzo de 2020), y 2) pacientes intervenidos de CCE el año previo. Se recogieron variables epidemiológicas, clínicas e histopatológicas, así como el estadio tumoral y el grado de riesgo. Resultados: Se incluyeron 248 pacientes (127 intervenidos antes de la pandemia y 121 intervenidos después de la pandemia). Tras el inicio de la pandemia, el porcentaje de CCE de alto riesgo aumentó significativamente de 32,3 a 45,5% (p=0,011). No obstante, no se encontraron diferencias significativas en el grosor tumoral, la invasión perineural o la presencia de metástasis. Conclusiones: Aunque no se produjo una reducción significativa en el número de CCE intervenidos después de la pandemia, ha habido un incremento significativo en los CCE de alto riesgo. Todo ello puede conllevar un incremento en la mortalidad por cáncer de piel en el futuro. (AU)


Background: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. Objective To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. Material & methods: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. Results: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. Conclusions: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future. (AU)


Asunto(s)
Humanos , Neoplasias Cutáneas , Detección Precoz del Cáncer , Carcinoma de Células Escamosas , Pacientes , Factores Epidemiológicos , Cirugía General , Grado de Riesgo , Estudios Transversales , España
10.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): 231-236, Mar. 2024. tab, graf
Artículo en Español | IBECS | ID: ibc-231393

RESUMEN

Antecedentes y objetivos: La calidad de vida profesional se define como el bienestar derivado del equilibrio entre las exigencias del ámbito laboral y los recursos para afrontarlas, el deterioro de la calidad de vida profesional puede contribuir en el síndrome de burnout o del profesional quemado. El objetivo de este estudio consiste en evaluar mediante cuestionario validado la calidad de vida profesional de los dermatólogos españoles. Material y métodos: Se diseñó un estudio transversal que incluyó dermatólogos españoles que respondieran a un formulario autoadministrado enviado a través de aplicaciones de mensajería online. El formulario incluyó datos sociodemográficos, 3 preguntas de respuestas abiertas y el Cuestionario de Calidad de Vida Profesional (CVP-35). Resultados: Se incluyó a 106 participantes en este estudio, siendo un 58% (62/106) mujeres. La edad media fue de 41 años (intervalo de confianza [IC] del 95%: 43,3-38,8). Las puntuaciones para el dominio «carga de trabajo» de CVP-35 fueron superiores en las mujeres (p=0,02) y en los jefes de servicio (p=0,005). La presión asistencial fue el tema tratado con más frecuencia como factor limitante de la calidad de vida laboral, y el principal cambio identificado tras la pandemia de COVID-19. Conclusiones: En nuestro estudio las mujeres refirieron una mayor carga de trabajo. El incremento de carga asistencial y de trabajo a distancia fueron los principales cambios por la pandemia de COVID-19. La presión asistencial es una gran limitante de la calidad de vida profesional de nuestros compañeros, reducirla mejoraría la satisfacción diaria y la calidad asistencial. (AU)


Background and objective: Quality of professional life (QPL) is defined as a sense of well-being derived from a balance between the challenges of work and the resources available to deal with them. Impaired QPL can contribute to burnout. The aim of this study was to evaluate QPL in Spanish dermatologists using a validated questionnaire. Material and methods: We designed a cross-sectional study in which Spanish dermatologists were invited to complete an online questionnaire sent out by messaging applications. The dermatologists were asked to provide sociodemographic information, answer 3 open questions, and complete the 35-item Spanish QPL questionnaire (Spanish abbreviation, CVP-35). Results: We analyzed the information submitted by 106 dermatologists (62 women, 58%) with a mean age of 41 years (95% CI, 43.3-38.8 years). Women and department heads scored significantly higher in the workload domain of the questionnaire (P=.02 and P=.005, respectively). A heavy caseload was mentioned as the main factor contributing to impaired QPL and the main change in the wake of the COVID-19 pandemic. Conclusions: Female dermatologists reported heavier workloads. Heavy caseloads and more remote work were the main changes identified after the COVID-19 pandemic. Heavy caseloads have a significant impact on the QPL of dermatologists in Spain. Reducing caseloads would improve general job satisfaction and quality of care provision. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Dermatología , Calidad de Vida , Satisfacción en el Trabajo , Agotamiento Psicológico , Dermatólogos , España , Estudios Transversales
11.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): t231-t236, Mar. 2024. tab, graf
Artículo en Inglés | IBECS | ID: ibc-231394

RESUMEN

Background and objective: Quality of professional life (QPL) is defined as a sense of well-being derived from a balance between the challenges of work and the resources available to deal with them. Impaired QPL can contribute to burnout. The aim of this study was to evaluate QPL in Spanish dermatologists using a validated questionnaire. Material and methods: We designed a cross-sectional study in which Spanish dermatologists were invited to complete an online questionnaire sent out by messaging applications. The dermatologists were asked to provide sociodemographic information, answer 3 open questions, and complete the 35-item Spanish QPL questionnaire (Spanish abbreviation, CVP-35). Results: We analyzed the information submitted by 106 dermatologists (62 women, 58%) with a mean age of 41 years (95% CI, 43.3-38.8 years). Women and department heads scored significantly higher in the workload domain of the questionnaire (P=.02 and P=.005, respectively). A heavy caseload was mentioned as the main factor contributing to impaired QPL and the main change in the wake of the COVID-19 pandemic. Conclusions: Female dermatologists reported heavier workloads. Heavy caseloads and more remote work were the main changes identified after the COVID-19 pandemic. Heavy caseloads have a significant impact on the QPL of dermatologists in Spain. Reducing caseloads would improve general job satisfaction and quality of care provision. (AU)


Antecedentes y objetivo: La calidad de vida profesional se define como el bienestar derivado del equilibrio entre las exigencias del ámbito laboral y los recursos para afrontarlas, el deterioro de la calidad de vida profesional puede contribuir en el síndrome de burnout o del profesional quemado. El objetivo de este estudio consiste en evaluar mediante cuestionario validado la calidad de vida profesional de los dermatólogos españoles. Material y métodos: Se diseñó un estudio transversal que incluyó dermatólogos españoles que respondieran a un formulario autoadministrado enviado a través de aplicaciones de mensajería online. El formulario incluyó datos sociodemográficos, 3 preguntas de respuestas abiertas y el Cuestionario de Calidad de Vida Profesional (CVP-35). Resultados: Se incluyó a 106 participantes en este estudio, siendo un 58% (62/106) mujeres. La edad media fue de 41 años (intervalo de confianza [IC] del 95%: 43,3-38,8). Las puntuaciones para el dominio «carga de trabajo» de CVP-35 fueron superiores en las mujeres (p=0,02) y en los jefes de servicio (p=0,005). La presión asistencial fue el tema tratado con más frecuencia como factor limitante de la calidad de vida laboral, y el principal cambio identificado tras la pandemia de COVID-19. Conclusiones: En nuestro estudio las mujeres refirieron una mayor carga de trabajo. El incremento de carga asistencial y de trabajo a distancia fueron los principales cambios por la pandemia de COVID-19. La presión asistencial es una gran limitante de la calidad de vida profesional de nuestros compañeros, reducirla mejoraría la satisfacción diaria y la calidad asistencial. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Dermatología , Calidad de Vida , Satisfacción en el Trabajo , Agotamiento Psicológico , Dermatólogos , España , Estudios Transversales
12.
Soil Use Manag ; 40(1): e12951, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38516181

RESUMEN

Riparian buffers are expedient interventions for water quality functions in agricultural landscapes. However, the choice of vegetation and management affects soil microbial communities, which in turn affect nutrient cycling and the production and emission of gases such as nitric oxide (NO), nitrous oxide (N2O), nitrogen gas (N2) and carbon dioxide (CO2). To investigate the potential fluxes of the above-mentioned gases, soil samples were collected from a cropland and downslope grass, willow and woodland riparian buffers from a replicated plot scale experimental facility. The soils were re-packed into cores and to investigate their potential to produce the aforementioned gases via potential denitrification, a potassium nitrate (KNO3 -) and glucose (labile carbon)-containing amendment, was added prior to incubation in a specialized laboratory DENItrification System (DENIS). The resulting NO, N2O, N2 and CO2 emissions were measured simultaneously, with the most NO (2.9 ± 0.31 mg NO m-2) and N2O (1413.4 ± 448.3 mg N2O m-2) generated by the grass riparian buffer and the most N2 (698.1 ± 270.3 mg N2 m-2) and CO2 (27,558.3 ± 128.9 mg CO2 m-2) produced by the willow riparian buffer. Thus, the results show that grass riparian buffer soils have a greater NO3 - removal capacity, evidenced by their large potential denitrification rates, while the willow riparian buffers may be an effective riparian buffer as its soils potentially promote complete denitrification to N2, especially in areas with similar conditions to the current study.

14.
Sci Total Environ ; 923: 171390, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38438044

RESUMEN

Marine microdebris (MDs, <5 mm) and mesodebris (MesDs, 5-25 mm), consist of various components, including microplastics (MPs), antifouling or anticorrosive paint particles (APPs), and metallic particles (Mmps), among others. The accumulation of these anthropogenic particles in macroalgae could have significant implications within coastal ecosystems because of the role of macroalgae as primary producers and their subsequent transfer within the trophic chain. Therefore, the objectives of this study were to determine the abundance of MDs and MesDs pollution in different species of macroalgae (P. morrowii, C. rubrum, Ulva spp., and B. minima) and in surface waters from the Southwest Atlantic coast of Argentina to evaluate the ecological damage. MDs and MesDs were chemically characterized using µ-FTIR and SEM/EDX to identify, and assess their environmental impact based on their composition and degree of pollution by MPs, calculating the Polymer Hazard Index (PHI). The prevalence of MDs was higher in foliose species, followed by filamentous and tubular ones, ranging from 0 to 1.22 items/g w.w. for MPs and 0 to 0.85 items/g w.w. for APPs. It was found that macroalgae accumulate a higher proportion of high-density polymers like PAN and PES, as well as APPs based on alkyd, PMMA, and PE resins, whereas a predominance of CE was observed in surrounding waters. Potentially toxic elements, such as Cr, Cu, and Ti, were detected in APPs and MPs, along with the presence of epiplastic communities on the surface of APPs. According to PHI, the presence of high hazard score polymers, such as PAN and PA, increased the overall risk of MP pollution in macroalgae compared to surrounding waters. This study provided a baseline for MDs and MesDs abundance in macroalgae as well as understanding the environmental impact of this debris and their bioaccumulation in the primary link of the coastal trophic chain.


Asunto(s)
Algas Marinas , Contaminantes Químicos del Agua , Plásticos , Monitoreo del Ambiente , Ecosistema , Argentina , Contaminantes Químicos del Agua/análisis , Microplásticos
15.
Actas Dermosifiliogr ; 2024 Feb 19.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38382752

RESUMEN

BACKGROUND AND OBJECTIVE: Burnout syndrome is a mental health disorder due to chronic occupational stress. Both burnout and associated comorbidities are prevalent among health care professionals, being medical residents a vulnerable group. Despite this, the scientific medical literature currently available on this issue in dermatology residents is scarce. The aim of this study was to analyze the prevalence of the burnout syndrome, anxiety, and depression in dermatology residents, and the associated risk factors. MATERIAL AND METHOD: This was a cross-sectional trial designed to include dermatology residents from Spain (from December 2022 through June 2023). A self-administered form was sent via online messaging applications, including validated scales to study professional quality of life, burnout syndrome, anxiety, and depression. RESULTS: A total of 48 dermatology residents were included in the study, 50% of whom (24/48) were women, with a mean age of 27 years (1.25). A total of 58.33% (28/48) of the residents had some degree of anxiety, 22.9% (11/48) some degree of depression, and 23.4% a moderate risk of burnout (11/48). Workload was the main risk factor associated with the 3 disorders studied, while managerial support or intrinsic motivation seem to play a protective role. CONCLUSIONS: Burnout syndrome and its comorbidities are both prevalent in dermatology residents in Spain and closely related to each other.

16.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(5): 209-212, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38401598

RESUMEN

Ocular neuromyotonia (ONM) is an infrequent disorder characterised by recurrent episodes of binocular diplopia caused by paroxysmal contraction of one or several extraocular muscles innervated by the same cranial nerve. It can be triggered spontaneously or caused by prolonged contraction of specific eye muscle(s) and is usually related to a local intracranial radiotherapy antecedent. We report the case of a 46-year-old woman who developed intermittent episodes of binocular diplopia eight years after radiotherapy for a nasopharyngeal carcinoma. After a complete neuro-ophthalmic assessment we diagnosed the case as an abducens nerve neuromyotonia. Although it is infrequent, radiotherapy to the nasopharynx is a possible cause of ONM, due to the proximity to the base of the skull and extraocular motor nerve pathways, especially that of the VI cranial nerve, as is the case presented in this article, about a patient whose history is a nasopharyngeal carcinoma treated with local radiotherapy.


Asunto(s)
Diplopía , Síndrome de Isaacs , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Femenino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/radioterapia , Síndrome de Isaacs/etiología , Síndrome de Isaacs/diagnóstico , Carcinoma Nasofaríngeo/radioterapia , Diplopía/etiología , Carcinoma/radioterapia , Enfermedades del Nervio Abducens/etiología , Traumatismos por Radiación/etiología , Traumatismos por Radiación/complicaciones , Radioterapia/efectos adversos
17.
J Chem Phys ; 160(7)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38364009

RESUMEN

Bromine atom (Br) reactions lead to ozone depletion in the troposphere and stratosphere. Photodegradation of bromocarbons is one of the main sources of bromine atoms in the atmosphere. Here, we use high-level ab initio methods, including spin-orbit effects, to study the photodissociation of the CH2Br radical. All possible fragmentation pathways, namely CH2Br + hν → CH2 + Br, HCBr + H, and CBr + H2, have been analyzed. Potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distance of each pathway have been calculated. Considering the actinic fluxes of solar irradiation in the troposphere and in the stratosphere in the relevant range of frequencies, it is found that the first five excited states of CH2Br can be accessed from the ground state. Analysis of the potential curves shows that the pathways producing CH2 + Br and HCBr + H can proceed through a fast direct dissociation mechanism, while the pathway leading to CBr + H2 involves much slower dissociation mechanisms like internal conversion between electronic states, predissociation, or tunneling through exit barriers. The main implications are that the two faster channels are predicted to be dominant, and the slower pathway is expected to be less relevant. The tropospheric and stratospheric solar actinic fluxes also allow for further dissociation of the HCBr and CBr fragments, generating additional Br atoms, provided that they survive possible collisions with other atmospheric reagents. Finally, we discuss the possible effect of each of the three CH2Br dissociation pathways on the depletion of atmospheric ozone.

20.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335333

RESUMEN

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

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