This paper argues that the central issue in the abortion debate has not changed since 1967 when the English parliament enacted the Abortion Act. That central issue concerns the moral status of the human fetus. The debate here is not, it is argued, primarily a moral debate, but rather a metaphysical debate and/or a theological debate--though one with massive moral implications. It concerns the nature and attributes that an entity requires to have "full moral standing" or "moral inviolability" including a "right to life". It concerns the question when, in its development from newly fertilised ovum to unequivocally mature, autonomous morally inviolable person does a human being acquire that nature and those attributes, and thus a "right to life". The paper briefly reviews standard answers to these questions, outlining some problems associated with each. Finally there is a brief discussion of one way in which the abortion debate has changed since 1967--notably in the increasingly vociferous claim, especially from disability rights sectors, that abortion on grounds of fetal abnormality implies contempt for and rejection of disabled people--a claim that is rebutted. (+info)
Knowledge and attitudes toward epilepsy among primary, secondary and tertiary level teachers.
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The attitudes toward people with epilepsy are influenced by the degree of knowledge of the condition. Teachers usually do not receive any formal instruction on epilepsy during their training. This study was done to access three hundred teachers' knowledge and attitudes toward epilepsy by answering a questionnaire in order to quantify their knowledge, attitude and practice toward epilepsy. Almost all the teachers had heard about epilepsy yet could not demonstrate discrimination among the students. Some teachers still thought that epilepsy was contagious. A few others either objected to having epileptic children in their classes or did not think that an epileptic child could achieve higher studies. The knowledge about the clinical characteristics and initial procedures to attend a person during a seizure was unsatisfactory. We conclude that schools should offer some kind of knowledge or assistance in health services and physicians must ensure that these teachers have sufficient knowledge of epilepsy. Also general public education campaigns should be encouraged in this field. (+info)
A technique for repeated sampling of the blood of individual resting fish.
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A dorsal cannulation technique is described. It has been employed for repeated blood sampling in unanaesthetized rainbow trout (Salmo gairdneri) kept singly in special receptacles described in the paper. The level of the studied haematological parameters (Haematocrit, Hb, glucose, lactate, K+, Na+, Ca2+) differed between fish kept in receptacles for 1 week and free-swimming fish, most probably owing to differences in the motility of the fish. The receptacle seems to minimize visual and handling disturbances, and permits both the standardization of experimental conditions and quick and easy sampling via the dorsal aorta cannula. The general variation in the blood parameter values was very small compared with the previously reported variation in such values for rainbow trout. (+info)
Reorganization in awake rat auditory cortex by local microstimulation and its effect on frequency-discrimination behavior.
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In common with other sensory cortices, the mammalian primary auditory cortex (AI) demonstrates the capacity for large-scale reorganization following many experimental situations. For example, training animals in frequency-discrimination tasks has been shown to result in an increase in cortical frequency representation. Such central changes-most commonly, an increase in central representation of specific stimulus parameters-have been hypothesized to underlie the improvements in perceptual acuity (perceptual learning) seen in many learning situations. The actual behavioral relevance of central reorganizations, however, remains speculative. Here, we directly examine this issue. We first show that stimulating the AI cortex of the awake rat with a weak electric current (intracortical microstimulation or ICMS) has the effect of inducing central reorganizations similar to those accompanying the traditional plasticity experiments (a result previously noted only in anesthetized preparations). Depending on the site of AI stimulation, ICMS enlarged the cortical representation of certain frequencies. Next we examined the direct perceptual consequences of ICMS-induced AI reorganization for the rat's ability to discriminate frequencies. Over the course of the experiment, we also detailed, and made comparisons between, the frequency-response characteristics of rat AI cortex in the awake and ketamine-anesthetized animal. AI cells that responded to pure tones were divided into two categories--strongly and weakly responsive--based on the strength of their evoked discharge. Individual cells maintained their respective response strengths in both awake and anesthetized conditions. Strongly responsive cells showed at least four different temporal responses and tended to be narrowly tuned. Their responses were stable over the long term. In general frequency-response characteristics were qualitatively similar in the anesthetized and awake animal; bandwidths tended to be broader in awake animals. Although both strong and weak cell populations respond to tones, only the strongly responsive cells fit into a tonotopically organized scheme. By contrast, weakly responsive cells did not exhibit a frequency mapping and may represent a more diffuse input to AI than that underlying strongly responsive cells. In general, the overall frequency organization of AI was found to be equally well expressed in both the awake and anesthetized rat. ICMS reorganization of AI did not alter frequency-discrimination behavior in the rat--either signal detectability or response bias--suggesting that an increase in central representation, by itself, is insufficient to account for perceptual learning. It is likely that cortical reorganizations that accompany perceptual learning are strongly keyed to specific behavioral contexts. (+info)
Investigation into non-monosynaptic corticospinal excitation of macaque upper limb single motor units.
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There has been considerable recent debate as to relative importance, in the primate, of propriospinal transmission of corticospinal excitation to upper limb motoneurons. Previous studies in the anesthetized macaque monkey suggested that, compared with the cat, the transmission of such excitation via a system of C3-C4 propriospinal neurons may be relatively weak. However, it is possible that in the anesthetized preparation, propriospinal transmission of cortical inputs to motoneurons may be depressed. To address this issue, the current study investigated the responses of single motor units (SMUs) to corticospinal inputs in either awake (n = 1) or lightly sedated (n = 3) macaque monkeys. Recordings in the awake state were made during performance of a precision grip task. The responses of spontaneously discharging SMUs to electrical stimulation of the pyramidal tract (PT) via chronically implanted electrodes were examined for evidence of non-monosynaptic, presumed propriospinal, effects. Single PT stimuli (up to 250 microA; duration, 0.2 ms, 2 Hz) were delivered during steady discharge of the SMU (10-30 imp/s). SMUs were recorded from muscles acting on the thumb (adductor pollicis and abductor pollicis brevis, n = 18), wrist (extensor carpi radialis, n = 29) and elbow (biceps, n = 9). In all SMUs, the poststimulus time histograms to PT stimulation consisted of a single peak at a fixed latency and with a brief duration [0.74 +/- 0.25 (SD) ms, n = 56], consistent with the responses being mediated by monosynaptic action of cortico-motoneuronal (CM) impulses. Later peaks, indicating non-monosynaptic action, were not present even when the probability of the initial peak response was low and when there was no evidence for suppression of ongoing SMU activity following this peak (n = 20 SMUs). Even when repetitive (double-pulse) PT stimuli were used to facilitate transmission through oligosynaptic linkages, no later peaks were observed (16 SMUs). In some thumb muscle SMUs (n = 8), responses to PT stimulation were compared with those evoked by transcranial magnetic stimulation, using a figure-eight coil held over the motor cortex. Responses varied according the orientation of the coil: in the latero-medial position, single peak responses similar to those from the PT were obtained; their latencies confirmed direct excitation of CM cells, and there were no later peaks. In the posterio-anterior orientation, responses had longer latencies and consisted of two to three subpeaks. At least under the conditions that we have tested, the results provide no positive evidence for transmission of cortical excitation to upper limb motoneurons by non-monosynaptic pathways in the macaque monkey. (+info)
Evidence for plateau potentials in tail motoneurons of awake chronic spinal rats with spasticity.
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Motor units of segmental tail muscles were recorded in awake rats following acute (1-2 days) and chronic (>30 days) sacral spinal cord transection to determine whether plateau potentials contributed to sustained motor-unit discharges after injury. This study was motivated by a companion in vitro study that indicated that after chronic spinal cord injury, the tail motoneurons of the sacrocaudal spinal cord exhibit persistent inward currents (I(PIC)) that cause intrinsically sustained depolarizations (plateau potentials) and firing (self-sustained firing). Importantly, in this companion study, the plateaus were fully activated at recruitment and subsequently helped sustain the firing without causing abrupt nonlinearities in firing. That is, after recruitment and plateau activation, the firing rate was modulated relatively linearly with injected current and therefore provided a good approximation of the input to the motoneuron despite the plateau. Thus in the present study, pairs of motor units were recorded simultaneously from the same muscle, and the firing rate (F) of the lowest-threshold unit (control unit) was used as an estimate of the synaptic input to both units. We then examined whether firing of the higher-threshold unit (test unit) was intrinsically maintained by a plateau, by determining whether more synaptic input was required to recruit the test unit than to maintain its firing. The difference in the estimated synaptic input at recruitment and de-recruitment of the test unit (i.e., change in control unit rate, DeltaF) was taken as an estimate of the plateau current (I(PIC)) that intrinsically sustained the firing. Slowly graded manual skin stimulation was used to recruit and then de-recruit the units. The test unit was recruited when the control unit rate was on average 17.8 and 18.9 Hz in acute and chronic spinal rats, respectively. In chronic spinal rats, the test unit was de-recruited when the control unit rate (re: estimated synaptic input) was significantly reduced, compared with at recruitment (DeltaF = -5.5 Hz), and thus a plateau participated in maintaining the firing. In the lowest-threshold motor units, even a brief stimulation triggered very long-lasting firing (seconds to hours; self-sustained firing). Higher-threshold units required continuous stimulation (or a spontaneous spasm) to cause firing, but again more synaptic input was needed to recruit the unit than to maintain its firing (i.e., plateau present). In contrast, in acute spinal rats, the stimulation did not usually trigger sustained motor-unit firing that could be attributed to plateaus because DeltaF was not significantly different from zero. These results indicate that plateaus play an important role in sustaining motor-unit firing in awake chronic spinal rats and thus contribute to the hyperreflexia and hypertonus associated with chronic injury. (+info)
The role of local mass media in promoting the consumption of iodized table salt.
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Iodine deficiency disorder (IDD) is currently an important public health problem in Turkey. The use of iodized salt is a sample and cheap solution. The purpose of this study was to determine the prevalence of iodized salt use in the Trabzon region and the effect of a local mass-media education program in increasing usage. The overall aim was to use the findings to inform future health management and health education activities, and shape further development of the IDD program. Prior to the intervention, the prevalence of iodized salt consumption was 54.5%. Following the 3-month education program it increased to 62.4%. There was a significant difference in the pre- and post-intervention findings (P = 0.00237). The results show that the use of local mass media is effective in raising the prevalence of iodized salt use. Local mass media could therefore be used as part of a national strategy to prevent iodine deficiency disorders. (+info)
Evaluation of 'Sun-safe': a health education resource for primary schools.
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The aim of the study was to assess the effectiveness of 'Sun-safe', a computer-based resource designed to promote skin cancer awareness and educate children, aged 10-11 years, about the effects of excessive exposure to the sun and associated skin cancer preventive behaviours. Effectiveness was measured by changes in knowledge, attitudes and behavioural intentions using a self-completed questionnaire. A cluster, controlled evaluation design was used. Twelve schools were randomly allocated to the intervention arms of the study (workbook or computer), with a further four schools acting as controls (no intervention). One school allocated to the computer group had serious technical problems with their computers on the day of the intervention and had to be excluded from the study, leaving six schools in the workbook group and five in the computer group. One class in each of the 15 schools participated. The questionnaire was administered before the intervention, the day after and 6 weeks thereafter. The primary outcome measures were changes in mean scores at 6 weeks. In all, 376 children, 83% of the roll, completed both pre- and 6-week tests. Mixed-model analysis, allowing for pre-intervention score and the cluster effect, showed significant increases in knowledge scores in all three groups [workbook 2.36, 95% confidence interval (CI): 1.66 to 3.05; computer 1.73, 95% CI: 1.00 to 2.46; control 0.93, 95% CI: 0.11 to 1.74], but only the workbook group was significantly better than the control group (1.43, 95% CI: 0.36 to 2.50) and there was no significant difference between the intervention groups (0.63, 95% CI: -0.38 to 1.63). With regard to attitudes, both interventions showed significantly greater increases in scores than the control group, but there was no significant difference between them (workbook 2.37, 95% CI: 1.27 to 3.47; computer 1.92, 95% CI: 0.76 to 3.09; control -0.01, 95% CI: -1.28 to 1.27). Although the mean increases for behavioural intentions scores were small (workbook 0.66, 95% CI: 0.26 to 1.05; computer 1.11, 95% CI: 0.70 to 1.51; control 0.08, 95% CI: -0.37 to 0.52), those for the intervention groups were significantly better than the control group, but were not significantly different from each other. The evaluation showed significant improvements in knowledge, attitudes and behavioural intentions, which were still present 6 weeks after the intervention. This suggests that interventions employing the Sun-safe workbook and computer-based resources could be most usefully put into effect in the week before the start of the summer holidays. (+info)