ABSTRACT
Echolocating bats have to assign the received echoes to the correct call that generated them. Failing to do so will result in the perception of virtual targets that are positioned where there is no actual target. The assignment of echoes to the emitted calls can be ambiguous especially if the pulse intervals between calls are short and kept constant. Here, we present first evidence that greater mouse-eared bats deal with ambiguity by changing the pulse interval more often, in particular by reducing the number of calls in the terminal group before landing. This strategy separates virtual targets from real ones according to their change in position. Real targets will always remain in a constant position, and virtual targets will jitter back and forth according to the change in the time interval.
Subject(s)
Chiroptera/physiology , Echolocation/physiology , Flight, Animal/physiology , Orientation/physiology , Adaptation, Physiological/physiology , Animals , Discrimination Learning/physiology , Male , Pattern Recognition, Physiological/physiology , Time FactorsABSTRACT
Triatominae bugs experience changes in the mechanical properties of their cuticle prior to feeding. This process-plasticization-allows a rapid stretching of the unsclerotized abdominal cuticle of triatominae larvae and it is evoked by sensory inputs related to feeding. We tested: (a) whether the cuticle recovers its original mechanical properties after plasticization, (b) whether repeated stimulation would be able to evoke recurrent plasticization along the same larval instar, (c) the temporal course of recovering cuticular stiffness. We injected Ringer solution into the body cavity of the bugs at constant pressure, using the injection rate (ml/min) as a measure of the cuticle extensibility. To trigger plasticization, individuals were allowed to feed on blood from an artificial feeder at 32+/-2 degrees C. After plasticization occurred, the abdominal cuticle gradually recovered its original mechanical properties. Bugs were capable of plasticizing for a second time when repeatedly stimulated. The effects of plasticization vanished between 1 and 2 h after stimulation. Although one full meal could suffice to accomplish moult in other Triatomine species, Triatoma infestans is able to feed repeatedly during a single larval instar. Accordingly to this, their cuticle recovers stiffness in some hours and becomes able to respond repeatedly to sensory inputs associated with feeding.
Subject(s)
Eating/physiology , Feeding Behavior/physiology , Integumentary System/physiology , Triatoma/physiology , Abdomen/anatomy & histology , Abdomen/growth & development , Animals , Biomechanical PhenomenaSubject(s)
Morphine/therapeutic use , Neoplasms/complications , Pain/drug therapy , Adult , Aged , Chronic Disease , Female , Humans , Injections, Spinal , Male , Middle Aged , Morphine/administration & dosageABSTRACT
The study was carried out on the experiences with 20 patients with low back pain. They were treated by thermoelectrocoagulation of the posterior lumbar roots. 60% optimal and 10% good results without permanent complications.
Subject(s)
Back Pain/surgery , Electrocoagulation , Spinal Nerve Roots/surgery , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Paraplegia/etiology , Postoperative Complications/etiologySubject(s)
Outpatient Clinics, Hospital , Pain Management , Evaluation Studies as Topic , Female , Hospitals, General , Humans , Male , Middle AgedABSTRACT
Diseases of the column and some psychic disturbances (e.g. neuroses) form the causes of transitory or chronic invalidity. From a psychological point of view, the lumbar region plays an important role in the polarisation of certain psychological conflicts: sexuality, aggressiveness, depression, frustration, exaggerated submission, etc. In consideration of this sensitivity of the lumbar region to certain psychic disturbances we have subjected a great number of women and men to a special neurological and clinical examination. Only in one per cent of the patients operated on no organic change was found, which underlines the importance and necessity of an appraisal of the personality of the patients with chronic, psychically caused pain. When this appraisal of the personality is omitted, diagnostic errors may occur that cannot be made good again.
Subject(s)
Back Pain/psychology , Somatoform Disorders/psychology , Adult , Back Pain/diagnosis , Back Pain/surgery , Diagnosis, Differential , Female , Humans , Intervertebral Disc Displacement/diagnosis , Male , Middle Aged , Sciatica/psychology , Somatoform Disorders/diagnosis , Somatoform Disorders/surgeryABSTRACT
We have studied in this work, from the neuropsychological point of view, sixteen patients (9 with tumor in the frontal lobe, 3 with temporal and temporo-parietal tumor and 4 with parietal, occipital and parieto-occipital tumor). The results show an intellectual damage when the work to carry out involves time, visualmotricity and perceptive-visual integration. We have likewise observed the appearance of many disorders of the spatial orientation, the perceptive visual integration, the graphomotricity and the reading process.
Subject(s)
Brain Neoplasms/complications , Cognition Disorders/etiology , Brain Neoplasms/psychology , Female , Humans , Male , Neuropsychological TestsABSTRACT
Tumors arising from the nerve sheaths are a controversial group of neoplasms because of disagreement regarding the clinical course and histopathologic characteristics. Malignant Schwannoma is a rare entity with aggressive biological behaviour (local infiltration and hematogenous metastases). The tumor arises from Schwann cells and may show diverse histological patterns. A malignant epithelioid paravertebral Schwannoma was diagnosed in a 48-year-old patient. Tumor metastases were demonstrated in the lungs, pericardium, liver, intestine, kidney, adrenals, bones and lymph nodes. The differential diagnosis and literature on this topic are commented on.
