Publications by authors named "Oberg P"

This systematic review synthesized prior quantitative research on individual, family, job, and organizational factors associated with retirement intentions (RI) among older long-term care (LTC) workers. Seven databases were searched for peer-reviewed studies. RI were defined as early (<65 years) or late (>65 years).

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Coiled coils with defined assembly properties and dissociation constants are highly attractive components in synthetic biology and for fabrication of peptide-based hybrid nanomaterials and nanostructures. Complex assemblies based on multiple different peptides typically require orthogonal peptides obtained by negative design. Negative design does not necessarily exclude formation of undesired species and may eventually compromise the stability of the desired coiled coils.

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We have previously described a technology based on diffuse reflectance of broadband light for measuring joint articular cartilage thickness, utilizing that optical absorption is different in cartilage and subchondral bone. This study is the first evaluation of the technology in human material. We also investigated the prospects of cartilage lesion imaging, with the specific aim of arthroscopic integration.

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Objective: We surveyed child and adolescent psychiatrists (CAPs) to characterize how they diagnose bipolar disorder (BPD) in children.

Methods: We approached by mail and then telephone 100 CAPs randomly sampled from five regions of the main professional organization of American CAPs; 53 CAPs were reached and agreed to participate. We asked about their training and practice setting, and asked them to name 10 symptoms indicative of BPD.

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We have investigated if features in the diffuse reflectance spectra from in vivo spectroscopic measurements of the tympanic membrane could aid the diagnosis of otitis media in children. Diffuse reflectance spectroscopy, in the visible wavelength range, was used in 15 ears from children with otitis media with effusion before and after myringotomy and in 15 healthy ears as a reference. Two previously published erythema detection algorithms yielded numerical quantities of haemoglobin content.

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A contact-free sensor consisting of two parallel optical-fibre arrays was designed to assess surface shapes of diffusely scattering media. By sequentially illuminating objects using one fibre array and detecting the diffusely back-scattered photons by the other, a source-detector intensity matrix was formed, where the matrix element (i, j) was the intensity at detector j when light source i was excited. Experimental data from convex and concave polyacetal plastic surfaces were recorded.

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A new principle for cartilage layer thickness assessments in joints is presented. It is based on the differences between the absorption spectra of cartilage and subchondral bone (containing blood). High-resolution ultrasound measurements of cartilage thickness were compared with reflection spectroscopy data from the same area of bovine hip joint condyles.

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Messages in the consumer culture are often youth oriented, aiming at the prevention of the bodily decay associated with biological aging. In gerontological discourses, this has been hypothesized to generate negative attitudes toward embodied aging and old age. Studies about general attitudes toward old age show that younger respondents have more negative attitudes than do older respondents, and gerontological discourses also hypothesize a gendered ageism, with especially negative attitudes toward elderly women.

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Objective: A new photoplethysmographic (PPG) device for respiratory and heart rate monitoring has been evaluated in the neonatal care units at the University Children's Hospital of Uppsala, Sweden. The purpose of this study was to compare this new device with more established techniques, i.e.

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Spectacular color changes of fishes, frogs and other lower vertebrates are due to the motile activities of specialized pigment containing cells. Pigment cells are interesting for biosensing purposes since they provide an easily monitored physiological phenomenon. Melanophores, containing dark brown melanin pigment granules, constitute an important class of chromatophores.

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We present a model for the activity of protein clusters based on a simultaneous desorption of an activator (agonist, substrate molecule, etc.) and an inactivator (antagonist, inhibitor, etc.) caused by the collision or interaction between two effector molecules (e.

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Black pigment cells called melanophores change colour in response to environmental changes and have lately been studied as promising biosensors. To further elucidate the intracellular processes involved in the colour changes of these cells, and to find optimal biosensing principles, the electric charge of intracellular pigment granules, melanosomes, has been determined in vitro by electrophoresis. Melanosomes from the two extreme states in the cell colour change (aggregated and dispersed melanosomes) were measured.

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Ten newborn infants, born at 25-41 wk of gestation and nursed in a neonatal intensive care unit or in a neonatal intermediate care unit, underwent monitoring of heart and respiratory rates with a new technique using an optical sensor, 0-60 d postnatally. The aim of this study was to compare the heart and respiratory rates recorded in infants by photoplethysmography with a probe positioned on three monitoring sites, namely the leg, buttock and interscapular region, with the rates recorded by ECG and transthoracic impedance, respectively. The recordings were compared in order to determine which individual heart beats and respiratory cycles were recorded with one or both relevant techniques.

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The tissue matrix in the human body is continuously in motion driven by forces generated by the circulatory and respiratory systems. The linear velocities recorded can be as high as 300 microm/s. The question raised: is the motion of tissue matrix generating an error signal in laser-Doppler (LD) recordings that is misinterpreted as solely a blood flow signal.

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A Windkessel model has been constructed with the aim of investigating the respiratory-volume dependence of the photoplethysmographic (PPG) signal. Experimental studies show a correlation between respiratory volume and the peak-to-peak value of the respiratory-induced intensity variations (RIIV) in the PPG signal. The model compartments are organised in two closed chambers, representing the thorax and the abdomen, and in a peripheral part not directly influenced by respiration.

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To evaluate the possibility of respiratory-volume measurement using photoplethysmography (PPG), PPG signals from 16 normal volunteers are collected, and the respiratory-induced intensity variations (RIIV) are digitally extracted. The RIIV signals are studied while respiratory volume is varied. Furthermore, respiratory rate, body posture and type of respiration are varied.

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This study pertains to the 71 patients who had received a diagnosis of cervico-brachial pain syndrome after thorough clinical examination of a total series of 300 patients, who had been referred to the National Insurance Hospital in Tranås because of chronic neck pain that interfered with their ability to work. Changes in trapezius muscle blood flow and EMG were examined and related to the anamnesis and physical findings. The microcirculation in the upper part of the right and left trapezius muscles was examined simultaneously by using optical laser-Doppler single-fibres after insertion into the muscle directly via the skin.

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The transmittance, reflectance and the angular dependence of coherent light at wavelengths of 632.8 and 750 nm in the cochlear bone in guinea pigs were measured by a single integrating sphere and a goniometer. The strict one-dimensional transport theory was applied to calculate the absorption and scattering coefficients.

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A new sensor for respiratory rate monitoring is described. The sensor uses an optical fibre that detects the evaporated humidity from the mouth and/or nose at each exhalation. The condensed humidity substantially alters the coupling of light from the optical fibre to the surrounding medium, which can be monitored by a photo-detector.

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A new laser Doppler flowmeter, based on a personal computer with a digital signal processor for detecting the blood perfusion in skeletal muscle, was designed and evaluated. An infrared laser diode (750 nm) fed a single optical fibre, 400 microns in diameter, which was introduced into the muscle. A PC equipped with a digital processing unit was used for emulation of the laser Doppler algorithm and for presentation of the measurement results.

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The single-fibre percutaneous laser Doppler technique has been used in previous studies of intramuscular blood flow. This method facilitates studies of blood flow in deep tissue volumes and minimises the tissue trauma. The technique has been further developed with the aim of improving the signal quality.

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A technique is described for intramuscular measurement of muscle blood flow in the forearm, by using a 0.5-mm thin optical single-fibre for laser Doppler flowmetry (LDF) inserted percutaneously. Continuous recordings were performed of the brachioradial muscle during an 11-min series of alternating 1-min periods of increased static contraction and rest determined by an electronic handgrip forcemeter and surface electromyography (EMG) of the muscle.

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The photoplethysmorgraphic signal (PPG) from forearm skin and the ECG were recorded simultaneously from healthy subjects. The optical signal was derived with a fibre-optic probe which consisted of 61 fibre pairs. The peak-to-peak averaged a.

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Mental stress was induced by the Stroop colour word task (CW task) and the effects on the microcirculation and electromyography (EMG) in the upper portion of the trapezius muscle were studied during a series of fatiguing, standardized static contractions. A lowered blood flow of the skin recorded continuously by laser-Doppler flowmetry (LDF) was used as a stress indicator in addition to an elevated heart rate. Muscle blood flow was recorded continuously by LDF using a single optical fibre placed inside the muscle, and related to surface EMG.

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