Riesgos psicosociales y calidad de vida en trabajadores de servicios oncológicos públicos / Psychosocial risks and quality of life among workers of public oncology services / Riscos psicossociais e qualidade de vida em trabalhadores de serviços públicos de oncologia

RESUMEN Introducción El trabajo desempeñado por personal de centros oncológicos genera impacto sobre ellos debido a situaciones a las que se ven expuestos, esto puede trascender en su calidad de vida. Objetivo Determinar la relación entre las variables biodemográficas, laborales, riesgos psicosociales, carga mental de trabajo y calidad de vida relacionada con salud en trabajadores de servicios oncológicos. Métodos Estudio correlacional en 113 trabajadores de servicios oncológicos de cuatro hospitales chilenos. Cuestionarios aplicados: Variables biodemográficas y laborales, Calidad de Vida Relacionada con Salud SF-36, Evaluación de riesgos psicosociales SUSESO-ISTAS 21 y Escala subjetiva de carga mental de trabajo. Resultados Variables sexo y turnos laborales presentaron correlación significativa con algún componente de la calidad de vida (p <0.05). Consulta médica (p <0.01), licencia médica (p <0.01) y problema de salud diagnosticado (p <0.05) manifestaron bajos niveles de calidad de vida. Se encontró correlación negativa tanto en los riesgos psicosociales con calidad de vida (p <0.05) como entre la carga mental de trabajo global con el componente de salud mental (p <0.01). Discusión Los trabajadores en centros oncológicos están expuestos a un mayor nivel de riesgo por las condiciones de la organización del trabajo, esto representan un riesgo a su salud. Conclusión Existe asociación entre algunas variables biodemográficas y laborales, riesgos psicosociales y carga mental con la calidad de vida relacionada con salud en trabajadores de servicios de oncología de hospitales públicos chilenos. Las organizaciones deberían implementar estrategias que permitan detectar y prevenir la exposición a riesgos psicosociales y sobrecarga mental de trabajo.

ABSTRACT Introduction The activities which workers carry out in centers of oncology can have importants impacts on their quality of life. Objective To determine the associations among biodemographical and work-related variables, psychosocial risks, work-related mental load, and health-related quality of life among workers of services of oncology. Methods This is a correlational study with 113 workers of oncology services in 4 hospitals in Chile. The questionnaires used were: Biodemographical and work-related variables, Health-Related Quality of Life SF-36, Assessment of psychosocial risks SUSESO-ISTAS 21, and the Subjective scale of mental load from work. Results The variables sex and working shifts showed a significant correlation with some components of quality of life (p <0.05), medical consultation (p <0.01), medial license (p <0.01), and diagnosed health problems (p <0.05) showed low levels in quality of life. A negative correlation was found in psychosocial risks with quality of life (p <0.05), and mental load and mental health (p <0.01). Discussion Workers in centers of oncology have a higher health risk as a result of the conditions of their jobs. Conclusion There are associations among some biodemographical and work-related variables, psychosocial risks, mental load, and health-related quality of life, in terms of health among workers in services of oncology in public hospitals of Chile. Organizations should implement strategies aimed at detecting and preventing exposure to psychosocial risks and mental overload.

RESUMO Introdução O trabalho realizado pelos funcionários do centro oncológico gera impacto neles devido às situações a que estão expostos, isso pode transcender na sua qualidade de vida. Objetivo Determinar a relação entre variáveis biodemográficas, laborais, riscos psicossociais, carga mental de trabalho e qualidade de vida relacionada à saúde em trabalhadores de serviços de oncologia. Métodos Estudo correlacional em 113 trabalhadores de serviços oncológicos de quatro hospitais chilenos. Questionários aplicados: Variáveis biodemográficas e laborais, Qualidade de Vida Relacionada à Saúde SF-36, Avaliação de riscos psicossociais SUSESO-ISTAS 21 e Escala de carga mental subjetiva. Resultados As variáveis sexo e turnos de trabalho apresentaram correlação significativa com algum componente da qualidade de vida (p <0.05). Consulta médica (p <0.01), licença médica (p <0.01) e problema de saúde diagnosticado (p <0.05) apresentaram baixos níveis de qualidade de vida. Foi encontrada correlação negativa tanto nos riscos psicossociais com a qualidade de vida (p <0.05) quanto entre a carga de trabalho mental geral e o componente de saúde mental (p <0.01). Discussão Os trabalhadores dos centros oncológicos estão expostos a um maior nível de risco devido às condições de organização do trabalho, o que representa um risco para a sua saúde. Conclusão Existe associação entre algumas variáveis biodemográficas e laborais, riscos psicossociais e carga de trabalho mental com a qualidade de vida relacionada à saúde em trabalhadores de serviços de oncologia de hospitais públicos chilenos. As organizações devem implementar estratégias para detectar e prevenir a exposição a riscos psicossociais e sobrecarga mental de trabalho.

Hallazgos tempranos y tardíos en la resonancia cerebral de dos hermanos con síndrome de Hunter / Early and late brain resonance findings of two siblings with Hunter syndrome

Introducción: La mucopolisacaridosis de tipo II (MPS II) es una enfermedad lisosómica causada por deficiencia de la enzima iduronato-2-sulfatasa, ligada al cromosoma X, y produce un gran espectro de manifestaciones clínicas. Caso clínico: Se presenta el caso clínico de dos hermanos con MPS II de diferente origen paterno con la misma mutación genética; la edad en el momento del diagnóstico fue de 5 años (caso 1) y de 8 meses (caso 2). Dichos hermanos presentan hallazgos diferentes en la resonancia magnética cerebral entre sí: el caso 1 presentó hallazgos clásicos para la edad, y el caso 2 presentó múltiples hallazgos tempranos, como espacios perivasculares dilatados de hasta 9,5 mm y megacisterna magna, entre otros, sin presentar manifestaciones neurológicas. Conclusiones: La afectación cerebral del paciente del caso 2 se presentó antes del año de edad y previa a la hepatoesplenomegalia. La resonancia magnética se convierte en una herramienta de diagnóstico temprano para la MPS II.(AU)

Introduction: Mucopolysaccharidosis type II (MPS II) is a lysosomal disease caused by deficiency of the enzyme iduronate-2-sulfatase (IDS), linked to the X chromosome, producing a wide spectrum of clinical manifestations. Case report: We present the case of two siblings with MPS II of different paternal origin with the same genetic mutation; the age at the time of diagnosis was 5 years of age (case 1) and 8 months of age (case 2). These brethren present different findings in brain magnetic resonance imaging (MRI) with each other, case 1 presented classic findings for age, case 2 presented multiple early findings, such as dilated perivascular spaces up to 9.5 mm, magna megacisterna, among others; without neurological manifestations. Conclusion: This patient’s brain compromise was presented before the year of age and prior to hepatosplenomegaly, thus, MRI becomes an early diagnostic tool for MPS II.(AU)

Early and late brain resonance findings of two siblings with Hunter syndrome. / Hallazgos tempranos y tardíos en la resonancia cerebral de dos hermanos con síndrome de Hunter.

INTRODUCTION: Mucopolysaccharidosis type II (MPS II) is a lysosomal disease caused by deficiency of the enzyme iduronate-2-sulfatase (IDS), linked to the X chromosome, producing a wide spectrum of clinical manifestations. CASE REPORT: We present the case of two siblings with MPS II of different paternal origin with the same genetic mutation; the age at the time of diagnosis was 5 years of age (case 1) and 8 months of age (case 2). These brethren present different findings in brain magnetic resonance imaging (MRI) with each other, case 1 presented classic findings for age, case 2 presented multiple early findings, such as dilated perivascular spaces up to 9.5 mm, magna megacisterna, among others; without neurological manifestations. CONCLUSION: This patient's brain compromise was presented before the year of age and prior to hepatosplenomegaly, thus, MRI becomes an early diagnostic tool for MPS II.

TITLE: Hallazgos tempranos y tardíos en la resonancia cerebral de dos hermanos con síndrome de Hunter.Introducción. La mucopolisacaridosis de tipo II (MPS II) es una enfermedad lisosómica causada por deficiencia de la enzima iduronato-2-sulfatasa, ligada al cromosoma X, y produce un gran espectro de manifestaciones clínicas. Caso clínico. Se presenta el caso clínico de dos hermanos con MPS II de diferente origen paterno con la misma mutación genética; la edad en el momento del diagnóstico fue de 5 años (caso 1) y de 8 meses (caso 2). Dichos hermanos presentan hallazgos diferentes en la resonancia magnética cerebral entre sí: el caso 1 presentó hallazgos clásicos para la edad, y el caso 2 presentó múltiples hallazgos tempranos, como espacios perivasculares dilatados de hasta 9,5 mm y megacisterna magna, entre otros, sin presentar manifestaciones neurológicas. Conclusiones. La afectación cerebral del paciente del caso 2 se presentó antes del año de edad y previa a la hepatoesplenomegalia. La resonancia magnética se convierte en una herramienta de diagnóstico temprano para la MPS II.

Fucosyltransferase gene expression in goat endometrium during the estrous cycle and early pregnancy.

Regulation of the expression of the alpha(1,2)fucosyltransferase (FUT) genes and their enzymatic products, including the H-type 1 antigen (HT1), on the luminal surface of the uterus is believed to be critical for establishment of pregnancy in mammals. The FUT1 gene is a marker for conception rates in dairy cows and HT1 is a marker for uterine receptivity in rodents. To determine the spatiotemporal expression patterns of FUT1 and FUT2 genes in goats, endometrial tissues were obtained on six days spanning the estrous cycle (Days 5, 11, 13, 15, 17 and 19) and seven days spanning early pregnancy (Days 5, 11, 13, 15, 17, 19 and 25). In all data, we found no effect of status (cyclic or pregnant; P > 0.1) and pooled data where appropriate. We cloned FUT1 cDNA from goat endometrium and made probes from it for Northern and slot blot analyses. The analyses indicated that FUT1 gene expression was high until Day 13, and then declined. In situ hybridization revealed a change in the cell-specificity of FUT1 gene expression over the estrous cycle and early pregnancy. In situ hybridization signal intensity scores indicated that FUT1 expression by uterine epithelium was high on Day 5, moderate on Day 11, and minimal on subsequent days. In situ hybridization signals in uterine glandular epithelial cells remained high from Day 5 to Day 13, with weaker signals thereafter. Quantitative reverse transcription-PCR (RT-qPCR) assays were used for quantitation of FUT1 and FUT2 mRNAs. Quantitative RT-qPCR data were generated from endometrium collected from cyclic and pregnant animals on Days 5, 11 and 17. Relative levels of FUT1 mRNA were high on Days 5 and 11, but then fell 5-fold by Day 17 (P < 0.01). FUT2 mRNA concentrations were below the accurate detectable limit of the assay. High levels of HT1 were observed on the apical surface of uterine luminal epithelia on Days 5, 15, 17 and 19, with much lower levels on Days 11 and 13. Thus, data suggests that FUT1 is the primary enzyme responsible for the high levels of HT1 antigen present on the uterine luminal epithelium between Days 5 and 11 of the estrous cycle and early pregnancy. But changes in the expression of the FUT1 gene does not directly correlate to HT1 staining, which increased from Day 13-15. Future studies are required to understand the regulation of the HT1 antigen on the luminal surface of endometrium.

Prospective phase-II-study evaluating postoperative radiotherapy of cervical and endometrial cancer patients using protons - the APROVE-trial.

BACKGROUND: The prognosis for patients with cervical or endometrial cancer has improved over the last decades. Thus, reducing therapy-related toxicity and impact on quality of life have become more and more important. With the development of new radiotherapy techniques like IMRT (Intensity-modulated radiotherapy) the incidence of acute and chronic toxicities has already been reduced. Nevertheless, rates of complications requiring medical treatment range from 0.7-8% according to literature. 7.7% of patients develop severe complications after 5 years with an increasing risk for complications of 0.3%/year. Particularly, the volume of the small and large bowel receiving low doses (15 Gy) has been shown to be a predictive factor for the development of higher bowel toxicity. With the introduction of proton therapy into clinical practice, there are new opportunities for optimization of organ at risk-sparing thus possibly reducing toxicity. METHODS/DESIGN: The APROVE study is a prospective single-center one-arm phase-II-study. Patients with cervical or endometrial cancer after surgical resection who have an indication for postoperative pelvic radiotherapy will be treated with proton therapy instead of the commonly used photon radiation. A total of 25 patients will be included in this trial. Patients will receive a dose of 45-50.4 GyE in 1.8 GyE fractions 5-6 times per week using active raster-scanning pencil beam proton radiation. Platinum-based chemotherapy can be administered if indicated. For treatment planning, rectum, sigma, large and small bowel, bladder and femoral heads are defined as organs at risk. The CTV is defined according to the RTOG consensus guidelines. DISCUSSION: The primary endpoint of the study is the evaluation of safety and treatment tolerability of pelvic radiation using protons defined as the lack of any CTC AE Grade 3 or 4 toxicity. Secondary endpoints are clinical symptoms and toxicity, quality of life and progression-free survival. The aim is to explore the potential of proton therapy as a new method for adjuvant pelvic radiotherapy to decrease the dose to the bowel, rectum and bladder thus reducing acute and chronic toxicity and improving quality of life. TRIAL REGISTRATION: Registered at https://clinicaltrials.gov , ClinicalTrials.gov Identifier: NCT03184350 , registered 09 June 2017, enrolment of the first participant 19 June 2017.

Successful treatment of a recurrent granulation polyp in the airways with high-dose-rate brachytherapy: a case report.

BACKGROUND: Benign central airway tumors are very rare diseases. Their unspecific symptoms are responsible for late diagnosis. Endoscopic interventions with different techniques and tools are widely used for their treatment. However, in certain cases interventional endoscopy might be unsuccessful and therefore other methods such as high-dose-rate brachytherapy could be a therapeutic option. CASE PRESENTATION: A 76-year-old white German woman was referred to our clinic for an endoscopic treatment of a recurrent granulation polyp in her left main bronchus. She had dyspnea, coughing, and mucus retention. Three times resections via bronchoscopy were performed within less than a year. After each intervention the polyp regrew inside her left main bronchus causing a repeat of the initial symptoms. She presented to our clinic less than 1 month since the last intervention. Twice we performed a rigid bronchoscopy in total anesthesia where we resected the granulation polyp with a snare wire loop and did an argon plasma coagulation of its base. Due to the recurrent growing of the granuloma, we performed a high-dose-rate brachytherapy in conscious sedation after another interventional bronchoscopy with a resection of the polyp and argon plasma coagulation of the base. Three months after brachytherapy our patient came to our clinic for a follow-up with none of the initial symptoms. Only a small remnant of the polyp without a significant occlusion of her bronchus was visualized by bronchoscopy. Furthermore, 6 months after brachytherapy she was not presenting any of the initial symptoms. CONCLUSIONS: This case report shows that high-dose-rate brachytherapy is a therapeutic option for the treatment of benign airway stenosis when other interventional treatments are not or are less than successful. However, further investigations are needed to prove the effectiveness and reliability of the method.

Leg loss in Lutzomyia longipalpis (Diptera: Psychodidae) due to pyrethroid exposure: Toxic effect or defense by autotomy?

BACKGROUND & OBJECTIVES: Phlebotomine sandflies lose their legs after exposure to pyrethroids. In some insects leg loss helps to defend them from intoxication and predation, a phenomenon known as autotomy. A field observation has shown that sandflies that have lost some legs are still able to blood-feed. The aims of the study were to determine whether leg loss in sandflies, after exposure to deltamethrin, is due to autotomy and to establish the effect of the leg loss on blood-feeding. METHODS: Two experiments were carried out with Lutzomyia longipalpis: (i) Females were individually exposed to a sublethal time of deltamethrin and mortality and the number of leg loss were recorded; and (ii) Groups of females with complete legs or with 1-3 legs lost due to pyrethroid exposure were offered a blood meal and percentages of blood-fed and fully-fed females were recorded. RESULTS: Most females lost a median of 1 leg within 1-48 h post-exposure to deltamethrin. Mortality (after 24 h) was significantly higher for exposed females with lost legs (31.1%), compared to exposed females with complete legs (7.3%), and there were no differences in mortality between females with complete legs and the control (unexposed females). There were no differences between the three treatments in the percentages of blood-fed and fully-fed females. INTERPRETATION & CONCLUSION: Leg loss in sandflies is a toxic effect of pyrethroids and there was no evidence of autotomy. The loss of up to three legs after exposure to pyrethroids does not affect blood-feeding behaviour in laboratory and probably also in wild conditions.

In quest of cathode materials for Ca ion batteries: the CaMO3 perovskites (M = Mo, Cr, Mn, Fe, Co, and Ni).

Basic electrochemical characteristics of CaMO3 perovskites (M = Mo, Cr, Mn, Fe, Co, and Ni) as cathode materials for Ca ion batteries are investigated using first principles calculations at the Density Functional Theory level (DFT). Calculations have been performed within the Generalized Gradient Approximation (GGA) and GGA+U methodologies, and considering cubic and orthorhombic perovskite structures for CaxMO3 (x = 0, 0.25, 0.5, 0.75 and 1). The analysis of the calculated voltage-composition profile and volume variations identifies CaMoO3 as the most promising perovskite compound. It combines good electronic conductivity, moderate crystal structure modifications, and activity in the 2-3 V region with several intermediate CaxMoO3 phases. However, we found too large barriers for Ca diffusion (around 2 eV) which are inherent to the perovskite structure. The CaMoO3 perovskite was synthesized, characterized and electrochemically tested, and results confirmed the predicted trends.

Enhanced displacement of a liquid pushed by a viscoelastic fluid.

We consider the displacement, in a rectangular channel, of a Newtonian oil pushed by different types of liquids (Newtonian, shear-thinning, viscoelastic) of slightly higher apparent viscosity. In the absence of viscoelastic effects the interface between the two fluids becomes sharper at larger velocities, so that the thickness of the lateral film left behind increases with the flow rate. On the contrary, with a viscoelastic fluid, the shape of the interface is almost independent of the velocity so that the thickness of the lateral film is approximately constant. Moreover this thickness decreases when the ratio of normal to tangential stresses increases, suggesting that this effect can be attributed to normal stress differences. A heuristic theoretical approach tends to confirm this statement.

Allometry and ontogeny in Callibia diana Stål (Mantodea: Acanthopidae).

The life-cycle of Callibia diana Stål is described and linear and geometric morphometrics are used for studying allometrics and shape changes throughout this neotropical mantid species' life-cycle. Significant changes were expected in the allometry and shape of the raptorial leg and abdomen, given the importance of hunting and reproduction. The allometric slopes were obtained by using total length as the independent variable. Geometric morphometrics of landmarks were used for frontal femur and tibia. Hunting and reproduction-related structures had the steepest slopes and positive allometries. Negative growth of both disc width and head width found in the last moulting event may be a consequence of prothoracic muscle growth which is responsible for predatory strike strength. The tibial claw and femur of the raptorial leg become larger, while their spines become more orthogonal to the longitudinal axes which may facilitate prey retention. These changes in mantid shape throughout ontogeny were consistent and suggested the resource allocation and development programming of the body that improved reaching distance and prey retention.

Allometry and ontogeny in Callibia diana Stål (Mantodea: Acanthopidae)

The life-cycle of Callibia diana Stål is described and linear and geometric morphometrics are used for studying allometrics and shape changes throughout this neotropical mantid species' life-cycle. Significant changes were expected in the allometry and shape of the raptorial leg and abdomen, given the importance of hunting and reproduction. The allometric slopes were obtained by using total length as the independent variable. Geometric morphometrics of landmarks were used for frontal femur and tibia. Hunting and reproduction-related structures had the steepest slopes and positive allometries. Negative growth of both disc width and head width found in the last moulting event may be a consequence of prothoracic muscle growth which is responsible for predatory strike strength. The tibial claw and femur of the raptorial leg become larger, while their spines become more orthogonal to the longitudinal axes which may facilitate prey retention. These changes in mantid shape throughout ontogeny were consistent and suggested the resource allocation and development programming of the body that improved reaching distance and prey retention.

Minimally invasive trans-portal resection of deep intracranial lesions.

BACKGROUND: The surgical management of deep intra-axial lesions still requires microsurgical approaches that utilize retraction of deep white matter to obtain adequate visualization. We report our experience with a new tubular retractor system, designed specifically for intracranial applications, linked with frameless neuronavigation for a cohort of intraventricular and deep intra-axial tumors. METHODS: The ViewSite Brain Access System (Vycor, Inc) was used in a series of 9 adult and pediatric patients with a variety of pathologies. Histological diagnoses either resected or biopsied with the system included: colloid cyst, DNET, papillary pineal tumor, anaplastic astrocytoma, toxoplasmosis and lymphoma. The locations of the lesions approached include: lateral ventricle, basal ganglia, pulvinar/posterior thalamus and insular cortex. Post-operative imaging was assessed to determine extent of resection and extent of white matter damage along the surgical trajectory (based on T (2)/FLAIR and diffusion restriction/ADC signal). RESULTS: Satisfactory resection or biopsy was obtained in all patients. Radiographic analysis demonstrated evidence of white matter damage along the surgical trajectory in one patient. None of the patients experienced neurological deficits as a result of white matter retraction/manipulation. CONCLUSION: Based on a retrospective review of our experience, we feel that this access system, when used in conjunction with frameless neuronavigational systems, provides adequate visualization for tumor resection while permitting the use of standard microsurgical techniques through minimally invasive craniotomies. Our initial data indicate that this system may minimize white matter injury, but further studies are necessary.

Necrosis cutánea de localización antebraquial trasreconstrucción de una fístula arteriovenosa en paciente en hemodiálisis / No disponible

No disponible

Some properties of the optical resonances in a single subwavelength slit.

Diffraction of TM-polarized waves by a slit in a thick screen of infinite conductivity is treated. The case of an arbitrary incident beam wave is considered. We study the resonances that appear when the wavelength of the incident beam wave is larger than the slit width, i.e., the subwavelength regime where a one-mode model for the slit can be considered. High anomalous values (resonances) of the transmission coefficient, the angular diffracted energy, and the magnetic field within the slit are analyzed. A simple linear relationship to determine the resonant wavelengths is proposed. We show that the transmission coefficient, the normal diffracted energy, and the magnetic field within the cavity are linear functions of the resonant wavelength and the thickness of the screen. Additionally and surprisingly, we reveal that under certain conditions the incident beam wave via the diffraction can give a suppressed light transmission; i.e., a minimum in the transmission is obtained where a maximum is expected.

Estado de enclaustramiento que simula muerte cerebral en un niño con síndrome de Guillain-Barré / Locked-in state mimicking cerebral death in a child with Guillain-Barre syndrome

No disponible

No disponible

Tumor filodes benigno de mama izquierda: a propósito de un caso / Left breast benign phylodes tumor: a purpose of a case

Femenina de 34 años de edad, quien refiere enfermedad, con una tumoración en la mama izquierda de 6 meses de evolución, que fue aumentando progresivamente de tamaño. Se diagnóstico un Tumor Filodes benigno de mama izquierda, que fue estudiado y llevado a resolución quirúrgica sin complicaciones ni recidivas hasta la actualidad. El Tumor Filodes es una patología poco frecuente que representa menos del 1 por ciento de todos los tumores mamarios, con un comportamiento biológico variable, aunque la mayoría son benignos existe una variante histológica maligna que puede dar metástasis a distancia. Debe ser resecado quirúrgicamente con márgenes adecuados para evitar recidivas y mantenerse una vigilancia clínica post-operatoria estricta durante un periodo no menor de 2 años.

Hemangioma deformante cervical derecho: a propósito de un caso / Deformans right cervical hemangioma: a purpose of a case

Masculino de 32 años de edad, con aumento de volumen progresivo en la cara lateral derecha del cuello, de 20 años de evolución. Se sometió a resolución quirúrgica sin complicaciones. La histopatología reveló un Hemangioma Cavernoso, un tumor vascular benigno poco común, que puede causar molestias estéticas y funcionales de acuerdo a su localización, así como complicaciones sistémicas relacionadas con síndromes asociados. Comúnmente aparece en etapa neonatal puede hacerlo en el adulto. No existe tendencia a la regresión. La cirugía es el tratamiento definitivo, siempre que la lesión sea circunscrita y no afecte a órganos vitales.

Rigorous theory of the diffraction of Gaussian beams by finite gratings: TM polarization.

Diffraction of TM-polarized Gaussian beams by N equally spaced slits (finite grating) in a planar perfectly conducting thick screen is treated. We extend to the TM polarization case the results of a previous paper where the TE polarization was considered. The far-field diffraction patterns, the transmission coefficient tau, and the normally diffracted energy E as a function of several optogeometrical parameters are analyzed within the so-called vectorial region. The existence of constant-intensity angles in the far field when the incident beam wave is scanned along the N slits is shown. In addition, the property E=Ntau/lambda, valid in the scalar region, is extended to the TM polarization case in the vectorial region, lambda being the wavelength. The coupling between slits is analyzed, giving an oscillating amplitude-decreasing function as the separation between slits increases, where the period for these oscillations is the wavelength lambda. Finally, the extraordinary optical transmission phenomena that appear when the wavelength is larger than the slit width (subwavelength regime) are analyzed.