A homogeneous (AMX) and two heterogeneous (MA-40, MA-41) anion-exchange membranes, as well as a heterogeneous cation-exchange membrane (MK-40), are studied by electronic scanning microscopy, voltammetry, and chronopotentiometry. The presence of conducting and nonconducting regions on the surfaces of heterogeneous membranes is established by means of element analysis. The fraction of conducting regions is found by an image treatment. The surface of the AMX membrane was partially coated with microspots of a paint to make it heterogeneous (AMXheter). Voltammetric and chronopotentiometric measurements for AMX, AMXheter, and MA-41 membranes in NaCl solutions are carried out and the pH changes in the solution layers adjoining to these membranes are recorded. Analysis of obtained results shows that the concentration polarization of studied membranes characterized by the potential drop and the rate of water dissociation at the interface is mainly governed by the properties of their surfaces. It is found that the local limiting current density through conducting regions of a heterogeneous membrane is several times higher than the average limiting current through a homogeneous membrane.
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http://dx.doi.org/10.1016/j.jcis.2004.11.017 | DOI Listing |
Scand J Prim Health Care
January 2025
Unit of Physiotherapy, Department of Health and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Research has shown that physical activity on prescription (PAP), used in Swedish healthcare, increases patients' physical activity, but data are lacking regarding the long-term effects of PAP on exercise capacity. Therefor exercise capacity was evaluated in patients with metabolic risk factors, after 4.5 years of PAP treatment provided by physiotherapists in primary healthcare.
View Article and Find Full Text PDFExp Appl Acarol
January 2025
Laboratorio de Vectores y Enfermedades Transmitidas, Departamento de Ciencias Biológicas, CENUR Litoral Norte, Universidad de la República, Salto, Uruguay.
Babesia species (Piroplasmida) are hemoparasites that infect erythrocytes of mammals and birds and are mainly transmitted by hard ticks (Acari: Ixodidae). These hemoparasites are known to be the second most common parasites infecting mammals, after trypanosomes, and some species may cause malaria-like disease in humans. Diagnosis and understanding of Babesia diversity increasingly rely on genetic data obtained through molecular techniques.
View Article and Find Full Text PDFSupport Care Cancer
January 2025
Department of Nursing, Nanfang Hosptial of Southern Medical University, Guangzhou, 510515, People's Republic of China.
Purpose: Our study aim was to understand the (human and organizational) factors influencing fall risk among people with hematological malignancies using the Reason model as a framework, providing insights that can inform the development of safe and effective fall management strategies.
Methods: Purposive sampling was employed to conduct semi-structured interviews with 13 people with hematological malignancies and 12 nurses from the hematology department of a tertiary grade A hospital in Guangzhou from December 2023 to February 2024. The topic analysis method was utilized to analyze the interview data.
Eur J Pediatr
January 2025
Global Health and Tropical Medicine, GHTM, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, Lisbon, Portugal.
Purpose: Under-five mortality is a key public health indicator, highly responsive to preventive interventions. While global efforts have made strides in reducing mortality rates in this age group, significant disparities persist, particularly in Sub-Saharan Africa. This study aimed to systematically review the factors influencing under-five mortality in Africa, focusing on sociodemographic factors and health-related determinants.
View Article and Find Full Text PDFJpn J Radiol
January 2025
Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
Purpose: This study aimed to investigate whether vitamin K (menatetrenone) suppresses bone mineral density (BMD) loss in the irradiated region after radiotherapy (RT) in uterine cancer patients.
Materials And Methods: Our study included 34 patients who underwent whole pelvic irradiation for uterine cancer between 2001 and 2010. The patients were categorized in two groups: (1) Vitamin K (45 mg/day) administration group (group A) with 18 cases and (2) non-administered group (group B) with 16 cases.
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