Impacts of leaks and gas accumulation on closed chamber methods for measuring methane and carbon dioxide fluxes from tree stems.

Accurate measurements of methane (CH4) and carbon dioxide (CO2) fluxes from tree stems are important for understanding greenhouse gas emissions. Closed chamber methods are commonly employed for this purpose; however, leaks between the chamber and the atmosphere as well as gas accumulation, known as the concentration buildup effect, can impact flux measurements significantly. In this study, we investigated the impacts of concentration buildup and leaks on semi-rigid closed chamber methods. Field measurements were conducted on six tree species, including three species from a Mexican mangrove ecosystem and three species from a Magellanic sub-Antarctic forest. Systematic observations revealed significant leak flow rates, ranging from 0.00 to 465 L h-1, with a median value of 1.25 ± 75.67 L h-1. We tested the efficacy of using cement to reduce leaks, achieving a leak flow rate reduction of 46-98 % without complete elimination. Our study also demonstrates a clear and substantial impact of concentration buildup on CH4 flux measurements, while CO2 flux measurements were relatively less affected across all tree species studied. Our results show that the combined effects of leaks and concentration buildup can lead to an underestimation of CH4 emissions by an average of 40 ± 20 % and CO2 emissions by 22 ± 22 %, depending on the bark roughness. Based on these findings, we recall a straightforward yet effective method to minimize experimental errors associated with these phenomena, previously established, and reiterated in the current context, for calculating emissions that considers effects of leaks and concentration buildup, while eliminating the need for separate determinations of these phenomena. Overall, the results, combined with a literature review, suggest that our current estimates of GHG flux from tree stems are currently underestimated.

[Nurses' workload in hemodialysis units]. / Carga laboral de las enfermeras en Unidades de Hemodiálisis Crónica según dependencia y riesgo de los pacientes.

BACKGROUND: Knowing nurses' workload in hemodialysis units allows a better organization of human resources. AIM: To determine nurses' workload according to dependence and risk profiles of patients undergoing chronic hemodialysis. MATERIAL AND METHODS: One hundred fifty one patients from five hemodialysis units were selected and categorized in terms of dependence and risk using the instrument "Care according to dependence and risk in hemodialysis (CUDYR-DIAL). Nurses' activities for direct and indirect care and the time taken to complete those activities were measured. RESULTS: Per patient, nurses used 36.5 ±10.7 min for direct and 23.6 min for indirect care. The time required for direct care of patients at high risk with partial dependence and at high risk and partial self-sufficiency was 41.2 and 40.3 minutes respectively. CONCLUSIONS: During a dialysis session, nurses occupy 60% of their time providing direct care, mainly directed to patients categorized as being of high risk-partial dependence and high risk-partial self-sufficiency.

Carga laboral de las enfermeras en Unidades de Hemodiálisis Crónica según dependencia y riesgo de los pacientes / Nurses' workload in hemodialysis units

Background: Knowing nurses' workload in hemodialysis units allows a better organization of human resources. Aim: To determine nurses' workload according to dependence and risk profiles of patients undergoing chronic hemodialysis. Material and Methods: One hundred fifty one patients from five hemodialysis units were selected and categorized in terms of dependence and risk using the instrument "Care according to dependence and risk in hemodialysis (CUDYR-DIAL). Nurses' activities for direct and indirect care and the time taken to complete those activities were measured. Results: Per patient, nurses used 36.5 ±10.7 min for direct and 23.6 min for indirect care. The time required for direct care of patients at high risk with partial dependence and at high risk and partial self-sufficiency was 41.2 and 40.3 minutes respectively. Conclusions: During a dialysis session, nurses occupy 60% of their time providing direct care, mainly directed to patients categorized as being of high risk-partial dependence and high risk-partial self-sufficiency.

Validación al español de la escala de auto percepción de carga de cuidado / Validation into Spanish of the scale of self-perception of care burden

OBJETIVO: Validar al español la "Escala de Auto percepción de Carga" de Cousineau (2003) en su versión larga. MÉTODOS: La muestra estuvo formada por 161 pacientes sometidos a HDC. La escala se tradujo al español, se realizó una aplicación piloto en 10 pacientes y a continuación se elaboró el instrumento final que fue sometido al proceso de validación. RESULTADOS: La confiabilidad de la escala se mantuvo estable al ir eliminando cada uno de los ítems, fluctuando el Alpha de Cronbach entre 0.903 y 0.915. Por lo anterior, se decide mantener los 25 ítems originales en la versión en español. CONCLUSIÓN: La confiabilidad total del instrumento fue de 0.91, muy cercana a la obtenida en la versión original (0.93).

OBJETIVO: Validar, en la lengua española, la versión amplia de la "Escala de Autopercepción de carga de los cuidados" de Cousineau et al. MÉTODOS: La muestra estuvo constituída por 161 pacientes sometidos a hemodiálisis crónica en cinco Centros de Diálisis de la ciudad de Santiago - Chile. Esa Escala fue traducida al español y fue realizado un test piloto con diez pacientes; después de este procedimiento, se elaboró el instrumento final sometido al proceso de validación. RESULTADOS: La confiabilidad de la escala se mantuvo estable, con fluctuación del coeficiente alpha de Cronbach entre 0,903 y 0, 915, decidiéndose así, por mantener los 25 items originales en la versión en español. CONCLUSIÓN: La confiabilidad total del instrumento fue de 0,91, muy próxima de la obtenida en la versión original (0,93).

OBJECTIVE: To validate the Spanish language version of the broad "self-perception of burden of care scale" by Cousineau et al. METHODS: The sample consisted of 161 patients undergoing chronic hemodialysis at five dialysis centers in the city of Santiago - Chile. This scale was translated into Spanish and a pilot test was conducted with ten patients; after this procedure, we developed the final instrument to be subjected to the validation process. RESULTS: The reliability of the scale was stable, with fluctuations of the Cronbach's alpha coefficient of 0.903 and 0.915; we decided therefore to maintain the 25 original items within the Spanish version. CONCLUSION: The overall reliability of the instrument was 0.91, very close to that obtained in the original version (0.93).

[Depression and self-perceived burden of care by hemodialysis patients and their caregivers]. / Depresión y autopercepción de la carga del cuidado en pacientes en hemodiálisis y sus cuidadores.

OBJECTIVE: To determine the depressive symptoms, perceived social support, and self-perceived burden in chronic hemodialysis (CHD) patients; identify depressive symptoms and degree of fatigue in caregivers of CHD patients; evaluate-in patients-the association between self-perceived burden and perceived social support, and between self-perceived burden and depressive symptoms; and evaluate-in caregivers-the relationship between the number of years of care and the degree of fatigue reached. METHODS: A sample of 162 patient-caregiver pairs was selected in which an adapted version of the Multidimensional Scale of Perceived Social Support, along with the Self-perceived Burden Scale, the Center for Epidemiologic Studies Depression Scale, and the Fatigue Severity Scale were applied. The instruments were administered to patients by trained research assistants and, in the case of the caregivers, were self-administered. RESULTS: Forty percent of the patients were women, with an average age of 56 ± 14.9 years, whereas 75% of the primary caregivers were female spouses, with an average age of 50 ± 16.1 years. It was observed that the patients (40.74%) as well as the primary caregivers (43.82%) had depressive symptoms. A positive association (r = 0.43, P < 0.001) was found between self-perceived burden and the presence of depressive symptoms in patients. CONCLUSIONS: The majority of the primary caregivers were women and relatives of the patients. They perceived themselves as fatigued with care, as did the patients themselves. The presence of depressive symptoms was similar in patients and caregivers. There was a statistically significant association between self-perceived burden and the presence of depressive symptoms in patients.

Depresión y autopercepción de la carga del cuidado en pacientes en hemodiálisis y sus cuidadores / Depression and self-perceived burden of care by hemodialysis patients and their caregivers

OBJETIVO: Determinar síntomas depresivos, apoyo social percibido y autopercepción de carga en pacientes en hemodiálisis crónica (HDC); identificar síntomas depresivos y grado de fatiga en cuidadores de pacientes en HDC, y evaluar -en el paciente- la asociación entre autopercepción de carga y apoyo social percibido, y entre autopercepción de carga y síntomas depresivos, y -en el cuidador- la relación entre el número de años de cuidado y el grado de fatiga alcanzado. MÉTODOS: Se tomó una muestra de 162 díadas paciente-cuidador, a quienes se les aplicaron los instrumentos "escala adaptada de percepción de apoyo social", "escala de autopercepción de carga", "escala de depresión del Centro de Estudios Epidemiológicos" y "escala de severidad de la fatiga". Los instrumentos fueron aplicados a los pacientes por ayudantes de investigación entrenados y, en el caso de los cuidadores, fueron autoaplicados. RESULTADOS: Del total de pacientes, 40 por ciento fueron mujeres, con un promedio de edad de 56 ± 14,9 años, mientras que entre los cuidadores principales, 75 por ciento fueron mujeres, cónyuges, con una edad promedio de 50 ± 16,1 años. Se observó que tanto los pacientes (40,74 por ciento) como los cuidadores principales (43,82 por ciento) presentaban síntomas de depresión. Se encontró una asociación positiva (r = 0,43, P < 0,001) entre la autopercepción de carga y la presencia de síntomas depresivos en los pacientes. CONCLUSIONES: Los cuidadores principales son en su mayoría mujeres y familiares de los pacientes. Se perciben fatigados con el cuidado, al igual que lo perciben los propios pacientes. La presencia de síntomas depresivos es similar en pacientes y cuidadores, y hay una asociación estadísticamente significativa entre autopercepción de carga y presencia de síntomas depresivos en los pacientes.

OBJECTIVE: To determine the depressive symptoms, perceived social support, and self-perceived burden in chronic hemodialysis (CHD) patients; identify depressive symptoms and degree of fatigue in caregivers of CHD patients; evaluate-in patients-the association between self-perceived burden and perceived social support, and between self-perceived burden and depressive symptoms; and evaluate-in caregivers-the relationship between the number of years of care and the degree of fatigue reached. METHODS: A sample of 162 patient-caregiver pairs was selected in which an adapted version of the Multidimensional Scale of Perceived Social Support, along with the Self-perceived Burden Scale, the Center for Epidemiologic Studies Depression Scale, and the Fatigue Severity Scale were applied. The instruments were administered to patients by trained research assistants and, in the case of the caregivers, were self-administered. RESULTS: Forty percent of the patients were women, with an average age of 56 ± 14.9 years, whereas 75 percent of the primary caregivers were female spouses, with an average age of 50 ± 16.1 years. It was observed that the patients (40.74 percent) as well as the primary caregivers (43.82 percent) had depressive symptoms. A positive association (r = 0.43, P < 0.001) was found between self-perceived burden and the presence of depressive symptoms in patients. CONCLUSIONS: The majority of the primary caregivers were women and relatives of the patients. They perceived themselves as fatigued with care, as did the patients themselves. The presence of depressive symptoms was similar in patients and caregivers. There was a statistically significant association between self-perceived burden and the presence of depressive symptoms in patients.