Sökning: "spontaneous activity"

Visar resultat 1 - 5 av 169 avhandlingar innehållade orden spontaneous activity.

  1. 1. Creating Optical Activity: Total Spontaneous Resolution and Viedma Ripening

    Detta är en avhandling från Göteborg : Göteborgs universitet

    Författare :Per Martin Björemark; Göteborgs universitet.; Gothenburg University.; [2017]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optical activity; absolute asymmetric synthesis; total spontaneous resolution; Viedma ripening; grinding; chirality; conglomerate; coordination compound; coordination polymer; single crystal X-ray diffraction; solvent free oxidation; nantioselective sulfide oxidation; solid state VCD;

    Sammanfattning : The creation of optical activity has been considered as something impossible even though reports of such creation via total spontaneous resolution since the 1940´s have been published. More recently Viedma ripening have been developed that also produce enantiopure bulk product. Both methods are examples of absolute asymmetric synthesis i.e. LÄS MER

  2. 2. Breaking the symmetry: creation and transfer of optical activity via total spontaneous resolution and stereoselective reactions

    Detta är en avhandling från Göteborg : Göteborgs universitet

    Författare :Susanne Olsson; Göteborgs universitet.; Gothenburg University.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; absolute asymmetric synthesis; enantioselective reactions; chirality; spontaneous resolution; conglomerate; organometallic chemistry; coordination compounds; attritionenhanced deracemisation; polymorphism; organolithium compounds; single-crystal X-ray crystallography;

    Sammanfattning : The generation of optical activity from achiral or racemic precursors – absolute asymmetric synthesis – is discussed in relation to the origin of biomolecular homochirality but is also often (incorrectly) regarded as being impossible. One approach to absolute asymmetric synthesis is the use of compounds that form chiral crystals. LÄS MER

  3. 3. Mind in Motion: The utilization of noise in the cognitive process

    Detta är en avhandling från LUCS, Kungshuset, 222 22 LUND, Sweden

    Författare :Robert Pallbo; Lund University.; Lunds universitet.; [1997]
    Nyckelord :HUMANIORA; HUMANITIES; AI; image processing; spontaneous activity; motion detection; knowledge acquisition; homunculus; evolutionary epistemology; evolution; cognition; noise; neural networks; Psychology; Psykologi;

    Sammanfattning : The brain is not silent. Even in the absence of stimuli are the neurons activated every now and then in what is called "spontaneous" or "background activity" which provides a noisy background to the operation of the brain. This work shows how this noise can be utilized in the cognitive process. LÄS MER

  4. 4. Cursed complexity. Computational properties of subcortical neuronal microcircuitry in sensorimotor control

    Detta är en avhandling från Neural basis for sensorimotor control

    Författare :Anton Spanne; Lund University.; Lunds universitet.; [2015]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; spike firing statistics; spontaneous activity; sensorimotor control; tactile processing; cuneate nucleus; sparse coding; spinal border cells; cerebellum;

    Sammanfattning : One of the big obstacles for understanding the nervous system is its inherent complexity. It poses problems when interpreting both experimental and theoretical studies since we are currently forced to consider only reduced variants of the actual circuitry of the brain. LÄS MER

  5. 5. NO PAIN, STILL GAIN- cross-modality development learning guided by spinal spontaneous activity

    Detta är en avhandling från Alexandra Waldenström, Dept. of Physiological Sciences, Sect. for Neurophysiology, BMC F10, S-221 84 Lund, Sweden

    Författare :Alexandra Waldenström Ellervik; Lund University.; Lunds universitet.; [2004]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; neuropsykologi; neurofysiologi; Neurologi; Neurology; neuropsychology; development; spinal cord; activity-dependent learning and memory; pain; somatosensory; neurophysiology;

    Sammanfattning : Recent studies indicate that experience dependent mechanisms shape the pain system during the development. In view of that painful stimuli are rare during development it is not clear how this is accomplished. LÄS MER