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BACKGROUND: The experience of childbirth significantly influences women's perspectives and attitudes, which are shaped by whether their experiences were positive or negative. This study aims to assess knowledge and attitudes regarding childbirth methods and potential complications among women in Al-Baha, Saudi Arabia. METHODS: This cross-sectional study was conducted in the Al-Baha region of Saudi Arabia with 500 participants. Data collection was facilitated through online surveys. The survey was responded to by women residing in Al-Baha of reproductive age (18-45), including those who had given birth vaginally or via cesarean section within the past five years. The questionnaire covered sociodemographic aspects and assessed knowledge and attitudes toward vaginal delivery, cesarean section, and their respective complications. RESULTS: The study encompassed 500 participants, predominantly under 36 years of age (224 participants, 44.8%). A majority were married (355 participants, 71%) and held a university degree (358 participants, 71.6%). Notably, half of the participants were unemployed, and 365 (65.4%) were multiparous. Preferences for childbirth methods showed that 296 women (59.2%) favored vaginal delivery, while 100 women (20%) preferred cesarean section. Regarding knowledge about childbirth, 200 participants (40%) rated their knowledge as very good. CONCLUSION: The study reveals a preference for vaginal delivery among the women surveyed, with over half possessing adequate knowledge about postpartum complications. Women with only a diploma or expressing a preference for cesarean section displayed lower knowledge levels about these complications. It is recommended that medical professionals provide comprehensive information about various childbirth methods and their complications, indications, and benefits to expectant women.
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ââââBehçet disease (BD) is a recurrent, multisystemic autoimmune vasculitis that affects both small and large vessels. A combination of neurological signs and symptoms in BD is called neuro-Behçet syndrome (NBS). We present the case of a 31-year-old male diagnosed with chronic progressive NBS who presented with multiple relapsing episodes concurrent with infective endocarditis due to intravenous drug abuse, drug-induced hepatitis, acute kidney injury, and septic shock that is not related to BD. Neurological relapsing episodes were treated with steroids azathioprine and colchicine. At the same time, concurrent illnesses were managed appropriately. Infective endocarditis needed valve replacement surgery, and sepsis was treated with selected antibiotics. Fortunately, the patient's brain images and laboratory investigation improved accordingly. On average, patients with parenchymal neuro-Behçet syndrome (P-NBS) have a poor prognosis; within 10 years of diagnosis, 50% of those patients are severely disabled as our patient who became aphasic and quadriplegic.
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We report measurements of resonant thermal capillary oscillations of a hemispherical liquid gas interface obtained using a half bubble deposited on a solid substrate. The thermal motion of the hemispherical interface is investigated using an atomic force microscope cantilever that probes the amplitude of vibrations of this interface versus frequency. The spectrum of such nanoscale thermal oscillations of the bubble surface presents several resonance peaks and reveals that the contact line of the hemispherical bubble is pinned on the substrate. The analysis of these peaks allows us to measure the surface viscosity of the bubble interface. Minute amounts of impurities are responsible for altering the rheology of the pure water surface.
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The "free" water surface is generally prone to contamination with surface impurities, be they surfactants, particles, or other surface active agents. The presence of such impurities can modify flow near such interfaces in a drastic manner. Here we show that vibrating a small sphere mounted on an atomic force microscope cantilever near a gas bubble immersed in water is an excellent probe of surface contamination. Both viscous and elastic forces are exerted by an air-water interface on the vibrating sphere even when very low doses of contaminants are present. The viscous drag forces show a crossover from no-slip to slip boundary conditions while the elastic forces show a nontrivial variation as the vibration frequency changes. We provide a simple model to rationalize these results and propose a simple way of evaluating the concentration of such surface impurities.
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We use colloidal-probe atomic force microscope (AFM) to study the rheological behavior of polymer solutions confined between two surfaces: the surface of a sphere and a flat surface on which the fluid is deposited. Measurements of the hydrodynamic force exerted on the sphere by the flowing liquid allowed retrieving the viscosity of the solution for different distances between the sphere and the flat surface. This method has been experimentally tested for Newtonian fluids for which the viscosity does not vary versus the gap dimensions. On the other hand, for non-Newtonian fluids, such as the large molecular weight polymer solutions used here, the measured viscosity depends on the gap height D between the flat surface and the sphere. The decrease of the viscosity versus gap height is similar to previously observed variations in colloidal suspensions. Depletion of polymers in the gap region due to the high shear rates involved is a possible cause for such a variation.
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Ensayo de Materiales/métodos , Microscopía de Fuerza Atómica/métodos , Modelos Químicos , Modelos Moleculares , Polímeros/química , Reología/métodos , Soluciones/química , Coloides/química , Simulación por ComputadorRESUMEN
In this paper, a drainage experiment of water between a borosilicate sphere and a microstructured surface constituted by regularly spaced pillars is presented. The microstructured surface has two parts: on one part the liquid forms a Cassie interface and on the second it forms a Wenzel interface. The measured hydrodynamic drag force is larger on the Cassie part compared to the Wenzel part. Furthermore, for the Cassie part, from the hydrodynamic drag force measurements on a pillar and between pillars the corresponding local slip lengths have been extracted. The area average slip length on the surface is in agreement with the value expected by Philip's equation.
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Hidrodinámica , Modelos Químicos , Reología/métodos , Simulación por Computador , Fricción , Resistencia al Corte , Estrés Mecánico , Propiedades de Superficie , ViscosidadRESUMEN
In this paper, a review of different techniques used to measure the slip length on superhydrophobic surfaces with large slip length is presented. First, we present the theoretical models used to calculate the effective slip length on superhydrophobic surfaces in different configurations of liquid flow. Then, we present the different techniques used to measure the slip past these superhydrophobic surfaces: rheometry, particle image velocimetry, pressure drop, surface force apparatus and atomic force microscopy.
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Measurements of the velocity profile of water flowing on a glass surface using fluorescent nanoparticles and single fluorescent molecules as velocity probes show that the no slip boundary condition holds down to at least 10 nm from the surface. For water flowing on a hydrophobic solid surface, silanized glass, the no slip boundary condition fails, and a slip length of 45 nm is measured. These velocity measurements are complemented with atomic force microscopy measurements of dissipation on a small sphere oscillating near the surface with results in agreement with the velocity profiles.
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Experimental models of the potato primary transgenic plants which express the hybrid gene cry3aM-licBM2 have been created. Modecular analysis and the biotests of the experimental models allow proposing a new system of cry genes expression in plants. The system is based on the expression of hybrid genes possessing the sequence of reporter lichenase gene and the use as a regulator element of a light-induced promoter providing preferential expression of the controled genes only in green plant tissues (leaves)--the target tissues for pests. The lichanase presence in hybrid proteins facilitates selection and analysis of the expression level of the hybris proteins in transgenic organisms. Basing on the lichenase properties in hybrid proteins it seems possible to use this reporter system for transgene monitoring in agrocoenosis as this system is rather simple and precise and does not need large material and time expenses.
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Modelos Genéticos , Plantas Modificadas Genéticamente/genética , Solanum tuberosum/genética , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Escarabajos/fisiología , Endotoxinas/genética , Conducta Alimentaria/fisiología , Genes Reporteros , Glicósido Hidrolasas/genética , Proteínas Hemolisinas/genética , Control Biológico de Vectores/métodos , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/parasitología , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/parasitología , Proteínas Recombinantes de Fusión/genética , Saccharomyces cerevisiae/genética , Solanum tuberosum/enzimología , Solanum tuberosum/crecimiento & desarrollo , Solanum tuberosum/parasitologíaRESUMEN
Single-molecule spectroscopy (SMS) combines some of the advantages of local probe microscopies with those of optics. Since this field came into being 10 years ago, it has expanded at a breathtaking pace. From the first cryogenic experiments up to the recent studies of basic processes in molecular biology, single-molecule methods have found their way into an ever broadening range of applications. Their common feature is the complete elimination of ensemble averaging. By exposing individual variations as well as dynamical fluctuations, SMS provides new insights into any system with spatial or temporal inhomogeneity. The present article illustrates single molecule spectroscopic experiments at cryogenic temperatures, mainly from the authors' group. The results reviewed here range from molecular photophysics, to the dynamics of the solid matrix around the molecule, and to the interactions between a single molecule and electromagnetic fields, i.e., quantum optics. SMS is now ripe for a variety of applications in physical chemistry, such as, for example, surfaces, growth structures, catalysis, or porous media.