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Chloride ions play an important role in controlling excitability of principal neurons in the central nervous system. When neurotransmitter GABA is released from inhibitory interneurons, activated GABA type A (GABAA) receptors on principal neurons become permeable to chloride. Typically, chloride flows through activated GABAA receptors into the neurons causing hyperpolarization or shunting inhibiti

Multi-component transient signals show up in many different areas, most commonly in communication and radar but are also often found in measurements of human related signals, such as electrical responses of the heart and the brain. Transient signals are also typical in animal acoustic applications, e.g., dolphin echo locations and bird song syllables. The usual basis functions in linear modeling oMulti-component transient signals show up in many different areas, most commonly in communication and radar but are also often found in measurements of human related signals, such as electrical responses of the heart and the brain. Transient signals are also typical in animal acoustic applications, e.g., dolphin echo locations and bird song syllables. The usual basis functions in linear modeling o

Providing health and social care to older persons is challenging, since older persons often have multiple diseases and a complex health situation. Hence many professions and organisations are involved. Lack of interprofessional and interorganisational collaboration leads to fragmented care. Care planning meetings before hospital discharge have long been used to overcome this fragmentation, but mee

Periodogram averaging with multiple windows can be used in spectrum analysis of nonstationary data. Usually, however, the windows for the subspectra are equally weighted in the estimate. In this correspondence, a criterion for the optimization of weighting factors is formulated as the average of normalized bias, variance, or mean square error in a certain frequency interval around a predefined pea

Bleeding with difficulties obtaining haemostasis can be a catastrophe. This paper summarizes a symposium with the above title. A short introduction gives the background of normal haemostasis as well as iatrogenic vascular injuries as reflected in the Swedish vascular registry (Swedvasc). Practical guidelines are given on how to manage situations of severe haemorrhage with the help of pharmacologic

Describes a method to measure changes in the mid-latency auditory evoked potential (MLAEP) during anesthesia. It is claimed that the position of the Nb-trough of the MLAEP indicates the level of consciousness. The component shows graded changes corresponding to the dose of anesthetic and it exhibits stable reproducible properties between different subjects. The authors propose a system that reduce

A multiple window method for estimation of the peaked power density spectrum is designed. The method optimizes a filter function utilizing the Karhunen-Loeve basis functions of a known peaked spectrum as windows to reduce variance and bias in the locality of the frequency peak. For improving performance, a penalty function is used to suppress the sidelobes outside a given bandwidth. The improved w

We address the problem of detecting double-talk in a full duplex transmission line. A new double-talk detector (DTD) based on measuring the similarity between the far- and near-end speech signals is proposed. The detector is block oriented and operates in the frequency domain where the similarity between the signals is measured by means of the coherence function. The coherence is estimated with a

This paper deals with estimation of the waveform of a single event-related potential, sERP. An additive noise model is used for the measured signal and the SNR of the disturbed sERP is approximately 0 dB. The sERP is described by a series expansion where the basis functions are damped sinusoids. The fundamental basis function is estimated by the least squares Prony method, derived for colored nois

Rot in living trees cause substantial losses for the forestry industry. The common practice when evaluating forest stands for, e.g., purchase, is assessment based on visual signs. In this paper a new non-destructive assessment method based on the impact excitation method is proposed. The trunk of a living tree is excited by the impact of a hammer, and the vibrations are measured by accelerometers.

The glycosylated multivalent three-domain Kunitz inhibitor TFPI is a natural inhibitor of tissue factor-FVIIa complex in the presence of FXa. TFPI has an experimental antithrombotic capacity indistinguishable from LMWH in a prophylactic dose, regardless of glycosylation and of the third domain. An inherited equilibrium between antithrombosis and haemorrhage exists. The aim of the study was to eval

The response of a tree trunk to a hammer blow, measured by sensors positioned around the excited cross section, consists of two kinds of transient mechanical waves: longitudinal P- and transverse S-waves. The aim of this paper is to extract the velocity of the S-waves, using a filtering structure that emphasizes the waves heading in one of the directions along the circumference. By this approach,

This paper deals with noise suppression in multichannel measurements, using a certain signal model but without assuming stationarity of the signals involved. This enables application to signals whose spectral characteristics are time-variable. The novelty consists of an algorithm for obtaining an approximation of the Wiener filter for each channel. The filters are computed using the Weyl transform

Peak matched multiple windows are found as the Karhunen-Loeve basis functions of a predefined peaked spectrum. With a penalty function, an optimization procedure can be constrained with resulting control of sidelobes. Weighting factors, included in the averaging of the periodograms, can be designed to fulfill certain constraints. Desirable properties are low variance and small bias. This paper pre

The paper proposes a new multiple window method for estimating a peaked spectrum. The multiple windows are adapted to the signal, giving a less biased estimate for estimation of peaks than does the Thomson multiple window method. Still the result from estimation of a flat spectrum shows comparable results in variance reduction. The method is based on solution of an eigenvalue problem where the eig