O trabalho utiliza conceitos da economia do bem estar e a elasticidade da renda
tributável para analisar o custo social das reações comportamentais dos contribuintes
do imposto de renda sobre as pessoas físicas no Brasil, em resposta a uma mudança
de política tributária. A elasticidade da renda tributável despertou grande atenção
recente, motivada pela perspectiva de estimar em conjunto todas as reações
comportamentais a uma mudança no sistema tributário através de um único parâmetro,
mensurando custos de eficiência e de bem estar suportados pela economia de forma
relativamente simples. O trabalho aborda a utilização de medidas de variação de bem
estar para avaliar mudanças na política tributária e faz uma resenha da literatura sobre
a elasticidade da renda tributável, conceitos, características, vantagens e limitações.
Um modelo de preferências é especificado para exemplificar a dimensão das reações à
tributação e os custos de eficiência envolvidos, e discutir a viabilidade do emprego da
elasticidade da renda tributável como parâmetro estrutural.; This study aims to analyse the social cost and behavioural responses due the taxation of earned income in Brazil using welfare concepts and the elasticity of taxable income with respect to the net of tax rate. The elasticity of taxable income has deserved great attemption and is a main issue in public economics research agenda. Under some conditions...
Binding of the novel radioligand 3H-2-(2-dimethylaminomethyl-phenylsulphanyl)-5-methyl-phenylamine (3H-MADAM) to the serotonin transporter (SERT) was used to characterise a range of selective serotonin re-uptake inhibitors (SSRIs) in vitro and in vivo.3H-MADAM bound with high affinity in a saturable manner to both human SERT expressed in CHO cells (Kd=0.20 nM (pKd=9.74±0.12), Bmax=35±4 fmol mg−1 protein) and mouse cerebral cortex membranes (Kd=0.21 nM (pKd=9.66±0.10), Bmax=50±24 fmol mg−1 protein).Binding of 3H-MADAM was highly selective for SERT in vitro as demonstrated by the in vitro profile of MADAM tested at 75 different receptors, ion channels and transporters. This was further substantiated by the pharmacological profile of the binding. Hence, the binding of 3H-MADAM was potently inhibited by SSRIs but not by selective inhibitors of noradrenaline transport and dopamine transport. Likewise, a 5-HT2A/2C receptor antagonist did not inhibit 3H-MADAM binding.3H-MADAM binding in vivo was inhibited only by compounds which also inhibited the binding of 3H-MADAM in vitro (the SSRIs, mixed SERT/noradrenaline transport inhibitors and clomipramine), confirming the selectivity of 3H-MADAM for SERT also in vivo. Moreover, compounds effective in inhibiting 3H-MADAM binding were the only ones found to be active in the mouse 5-HTP potentiation test confirming the model as a behavioural correlate to in vivo 5-HT uptake.Finally...
An assessment was made of how the HIV epidemic may have influenced sexually transmitted disease (STD) epidemiology in Uganda, and how HIV would affect the effectiveness of syndromic STD treatment programmes during different stages of the epidemic. The dynamic transmission model STDSIM was used to simulate the spread of HIV and four bacterial and one viral STD. Model parameters were quantified using demographic, behavioural, and epidemiological data from rural Rakai and other Ugandan populations. The findings suggest that severe HIV epidemics can markedly alter STD epidemiology, especially if accompanied by a behavioural response. Likely declines in bacterial causes of genital ulcers should be considered in defining policies on syndromic STD management in severe HIV epidemics.
1. The NK1 tachykinin receptor agonists, septide, [Sar9,Met(O2)11]SP and [Pro9]SP produced locomotor hyperactivity (10-20 min) when injected intracerebroventricularly (i.c.v.) in the guinea-pig. The most potent in eliciting this hyperactivity was septide (from 0.63 to 5 micrograms), compared to [Sar9,Met(O2)11]SP, which was active at 2.5 and 5 micrograms and [Pro9]SP which induced a non-significant increase even at 10 micrograms. 2. Wet-dog shakes were elicited by septide, [Sar9,Met(O2)11]SP and [Pro9]SP injected by the i.c.v. route in the guinea-pig. [Sar9,Met(O2)11]SP, active from 0.16 to 2.5 micrograms was more potent than septide (active at 1.25 micrograms) and [Pro9]SP (active at 0.63 micrograms) in eliciting such behaviour. To a lesser extent, grooming was also observed after injection of these agonists. 3. The NK2 tachykinin receptor agonist, [Lys5,MeLeu9,Nle10]NKA(4-10), up to the dose of 10 micrograms i.c.v. had no effect in the guinea-pig. It neither modified locomotor activity nor induced a characteristic behavioural response. At higher doses (20 micrograms), some toxic effects were noted. 4. The NK3 tachykinin receptor agonist, senktide, contrasts with the NK1 receptor agonists in that it elicited only wet-dog shakes, at doses ranging from 0.32 to 1.25 micrograms. It neither modified locomotor activity (1 microgram) nor induced grooming (up to 5 micrograms) in the guinea-pig. 5. To our knowledge...
1. The repeated co-administration of the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (0.1 and 0.3 mg kg-1, i.p.) with nicotine (0.4 mg kg-1, s.c.) attenuated the development of tolerance to the locomotor depressant effect of the nicotine in rats. 2. The repeated co-administration of the competitive NMDA antagonist D-CPPene (SDZ EAA 494; 3-(2-carboxypiperazin-4-yl)-1-propenyl-1-phosphonic acid, 2 and 8 mg kg-1, i.p.) also attenuated tolerance to the locomotor depressant effect of nicotine. 3. Dizocilpine (0.3 mg kg-1, i.p.) pretreatment attenuated sensitization to the locomotor stimulant effect of nicotine (0.4 mg kg-1, s.c.) and prevented sensitization of nicotine-induced dopamine release in the nucleus accumbens. However, pretreatment with dizocilpine alone caused a modest enhancement of the behavioural response to a subsequent acute dose of nicotine. 4. D-CPPene (2.0 mg kg-1, i.p.) pretreatment prevented sensitization to the nicotine-induced dopamine release in the nucleus accumbens. There was no enhanced locomotor response that could be attributed to nicotine pretreatment when D-CPPene was co-administered with nicotine. However, pretreatment with D-CPPene alone enhanced the locomotor response to an acute dose of nicotine. 5. The results suggest the involvement of NMDA receptors in adaptations of the behavioural and neurochemical effects of nicotine that occur as a result of repeated administration of the drug.
The effects of chronic (14 day) administration to mice of the 5-HT1 agonists 8-hydroxy 2-(di-n-propylamino) tetralin (8-OH-DPAT) and 5-methoxy-3 (1,2,3,6-tetrahydropyridin-4-yl) IH indole (RU 24969) on the hypothermic response to 8-OH-DPAT and the locomotor response to RU 24969 have been examined. Chronic administration of 8-OH-DPAT (5 mg kg-1, s.c.) resulted in an attenuated hypothermic response to this drug given subcutaneously (s.c.) or intracerebroventricularly (i.c.v.) but did not alter the locomotor response to RU 24969. Chronic injection of RU 24969 (3 mg kg-1, i.p.) produced an attenuated locomotor response to this drug given i.p. or i.c.v. but not the hypothermic response to 8-OH-DPAT (0.5 mg kg-1, s.c.). Chronic administration of the putative presynaptic 5-HT1 antagonist isapirone (10 mg kg-1, i.p.) decreased the hypothermic response following 8-OH-DPAT injection but did not alter RU 24969-induced locomotion. Chronic treatment with 8-OH-DPAT (5 mg kg-1, s.c.) produced a modest enhancement of the 5-HT2 receptor-mediated head-twitch behaviour initiated by 5-hydroxytryptophan injection while chronic isapirone decreased this behavioural response. 5-HT2 receptor number in frontal cortex was unaltered by isapirone treatment but markedly decreased (34%) by chronic 8-OH-DPAT. These data suggest that chronic administration of the 5-HT1 agonists induces tolerance in their respective responses but not cross-tolerance...
The administration of 4-[2-(3-indolyl)ethyl]piperidine (LM 5008), a selective 5-hydroxytryptamine (5-HT) uptake blocker to rats pretreated with tranylcypromine (Tcp) resulted in a behavioural syndrome of locomotor hyperactivity which is indistinguishable from that following combined treatment with Tcp and L-tryptophan. A similar behavioural response was elicited by the administration of LM 5008 to rats pretreated with 5-hydroxytryptophan. The response to LM 5008 after monoamine oxidase (MAO) inhibition was abolished by pretreatment with p-chlorophenylalanine, indicating the involvement of 5-HT in producing the hyperactivity syndrome. The administration of imipramine and chlorimipramine in combination with Tcp also resulted in hyperactivity, but these drugs were much less potent than LM 5008 in producing the syndrome. In contrast to L-tryptophan, which can produce hyperactivity only after the inhibition of both type A and type B MAO, LM 5008 can elicit the syndrome after selective inhibition of MAO type A only but not after inhibition of MAO type B. The behavioural results indicate that when MAO type A is inhibited, LM 5008 treatment elicits hyperactivity by preventing the availability of 5-HT to be metabolized by MAO-B component.
The gene Nramp1 encoding the natural resistance associated macrophage protein (Nramp1) influences susceptibility to intracellular infections and autoimmune diseases, and the humoral response to stress. Nramp1 functions as a proton/divalent cation antiporter in the membranes of late endosomes/lysosomes, regulating cytoplasmic iron levels in macrophages. The Drosophila homologue of Nramp1 is expressed in sensory neurones and macrophages, and influences taste behaviour directly through divalent cation transport. Here we demonstrate that murine Nramp1 is also expressed on neurones as well as microglial cells in the brain and influences the behavioural response to stress, hypothalamus-pituitary-adrenal (HPA) axis activation and mortality following Toxoplasma gondii infection in control and pre-stressed mice. We hypothesise that, although differences in HPA activation translate into differences in adrenal enlargement and basal circulating corticosterone levels, the primary influence of Nramp1 is at the level of the neuronal response to stress. These results provide new insight into the possible roles of divalent cation transporters of the Nramp gene family in regulating metal ion homeostasis in the brain and its pathological implications.
Caliothrips phaseoli, a phytophagous insect, detects and responds to solar ultraviolet-B radiation (UV-B; λ ≤ 315 nm) under field conditions. A highly specific mechanism must be present in the thrips visual system in order to detect this narrow band of solar radiation, which is at least 30 times less abundant than the UV-A (315–400 nm), to which many insects are sensitive. We constructed an action spectrum of thrips responses to light by studying their behavioural reactions to monochromatic irradiation under confinement conditions. Thrips were maximally sensitive to wavelengths between 290 and 330 nm; human-visible wavelengths (λ ≥ 400 nm) failed to elicit any response. All but six ommatidia of the thrips compound eye were highly fluorescent when exposed to UV-A of wavelengths longer than 330 nm. We hypothesized that the fluorescent compound acts as an internal filter, preventing radiation with λ > 330 nm from reaching the photoreceptor cells. Calculations based on the putative filter transmittance and a visual pigment template of λmax = 360 nm produced a sensitivity spectrum that was strikingly similar to the action spectrum of UV-induced behavioural response. These results suggest that specific UV-B vision in thrips is achieved by a standard UV-A photoreceptor and a sharp cut-off internal filter that blocks longer UV wavelengths in the majority of the ommatidia.
We hypothesize that a visual prosthesis capable of evoking high-resolution visual perceptions can be produced using high-electrode-count arrays of penetrating microelectrodes implanted into the primary visual cortex of a blind human subject. To explore this hypothesis, and as a prelude to human psychophysical experiments, we have conducted a set of experiments in primary visual cortex (V1) of non-human primates using chronically implanted Utah Electrode Arrays (UEAs). The electrical and recording properties of implanted electrodes, the high-resolution visuotopic organization of V1, and the stimulation levels required to evoke behavioural responses were measured. The impedances of stimulated electrodes were found to drop significantly immediately following stimulation sessions, but these post-stimulation impedances returned to pre-stimulation values by the next experimental session. Two months of periodic microstimulation with currents of up to 96 μA did not impair the mapping of receptive fields from local field potentials or multi-unit activity, or impact behavioural visual thresholds of light stimuli that excited regions of V1 that were implanted with UEAs. These results demonstrate that microstimulation at the levels used did not cause functional impairment of the electrode array or the neural tissue. However...
Obesity is associated with an increase in the prevalence and severity of infections. Genetic animal models of obesity (ob/ob and db/db mice) display altered centrally-mediated sickness behaviour in response to acute inflammatory stimuli such as lipopolysaccharide (LPS). However, the effect of diet-induced obesity (DIO) on the anorectic and febrile response to LPS in mice is unknown. This study therefore determined how DIO and ob/ob mice respond to a systemic inflammatory challenge. C57BL/6 DIO and ob/ob mice, and their respective controls, were given an intraperitoneal (i.p.) injection of LPS. Compared with controls, DIO and ob/ob mice exhibited an altered febrile response to LPS (100 μg/kg) over 8 hours. LPS caused a greater and more prolonged anorexic effect in DIO compared with control mice and, in ob/ob mice, LPS induced a reduction in food intake and body weight earlier than it did in controls. These effects of LPS in obese mice were also seen after a fixed dose of LPS (5 μg). LPS (100 μg/kg) induced Fos protein expression in several brain nuclei of control mice, with fewer Fos-positive cells observed in the brains of obese mice. An altered inflammatory response to LPS was also observed in obese mice compared with controls: changes in cytokine expression and release were detected in the plasma...
The idea that an NMDA receptor (NMDAR)-dependent long-term potentiation-like process in the hippocampus is the neural substrate for associative spatial learning and memory has proved to be extremely popular and influential. However, we recently reported that mice lacking NMDARs in dentate gyrus and CA1 hippocampal subfields (GluN1ΔDGCA1 mice) acquired the open field, spatial reference memory watermaze task as well as controls, a result that directly challenges this view. Here, we show that GluN1ΔDGCA1 mice were not impaired during acquisition of a spatial discrimination watermaze task, during which mice had to choose between two visually identical beacons, based on extramaze spatial cues, when all trials started at locations equidistant between the two beacons. They were subsequently impaired on test trials starting from close to the decoy beacon, conducted post-acquisition. GluN1ΔDGCA1 mice were also impaired during reversal of this spatial discrimination. Thus, contrary to the widely held belief, hippocampal NMDARs are not required for encoding associative, long-term spatial memories. Instead, hippocampal NMDARs, particularly in CA1, act as part of a comparator system to detect and resolve conflicts arising when two competing...
Male moths use species-specific sex pheromones to identify and orientate toward conspecific females. Odorant receptors (ORs) for sex pheromone substances have been identified as sex pheromone receptors in various moth species. However, direct in vivo evidence linking the functional role of these ORs with behavioural responses is lacking. In the silkmoth, Bombyx mori, female moths emit two sex pheromone components, bombykol and bombykal, but only bombykol elicits sexual behaviour in male moths. A sex pheromone receptor BmOR1 is specifically tuned to bombykol and is expressed in specialized olfactory receptor neurons (ORNs) in the pheromone sensitive long sensilla trichodea of male silkmoth antennae. Here, we show that disruption of the BmOR1 gene, mediated by transcription activator-like effector nucleases (TALENs), completely removes ORN sensitivity to bombykol and corresponding pheromone-source searching behaviour in male moths. Furthermore, transgenic rescue of BmOR1 restored normal behavioural responses to bombykol. Our results demonstrate that BmOR1 is required for the physiological and behavioural response to bombykol, demonstrating that it is the receptor that mediates sex pheromone responses in male silkmoths. This study provides the first direct evidence that a member of the sex pheromone receptor family in moth species mediates conspecific sex pheromone information for sexual behaviour.
It is well documented that hypoxia and elevated ammonia, two conditions common in high intensity aquaculture systems, produce marked behavioural and physiological effects on a variety of fish species including Nile tilapia. However, literature on the compounded effects of these two stressors is virtually non-existent. Therefore, the present study aimed to examine the physiological and behavioural effects of elevated ammonia on the hypoxic response in Nile tilapia (Oreochromis niloticus). Minor differences in mean oxygen consumption (mg O2/L/h/g wet tissue) were observed between the 2-2.5 mg/L hypoxia group and the 2-2.5 mg/L hypoxia with ammonia group. Mean ventilation frequencies (opercular flaps/min) for both pre-hypoxia and during-hypoxia levels (mg/L DO) did not differ significantly between any of the control, hypoxia, and hypoxia with ammonia groups. No significant differences between mean lactate concentrations for control and treatment groups were found. Finally, changes in mean adenosine triphosphate and phosphocreatine concentrations across control and treatment groups did not show any significant differences. The obtained results were not consistent with literature that revealed marked responses in tilapia exposed to hypoxia and elevated ammonia...
Thyer, M.; Duncan, H.; Coombes, P.; Kuczera, G.; Micevski, T.
Fonte: Engineers Australia; AustraliaPublicador: Engineers Australia; Australia
Tipo: Conference paper
Publicado em //2009Português
Relevância na Pesquisa
The emergence of the Integrated Urban Water Management (IUWM) design paradigm which utilises interventions at the household scale to reduce the demand on large scale water supply infrastructure has driven the need for a greater understanding and ability to simulate urban water use dynamics at the household scale. Urban water use at the household scale is a probabilistic behavioural response by individuals to a set of drivers. This paper outlines a hierarchical urban water use modelling framework for the probabilistic behavioural modelling of urban water use. The top level consists of the main drivers of urban water use, the second level simulates the spatial variability between houses (varying number of people, and varying water use appliances) and the third level simulates the temporal variability of an individual house. The methodology for simulating household indoor water use within this framework is described in this study. This consists of probabilistically simulating water use occurrence and event volumes for different end use categories (shower, washing machine, toilet etc) at minute time steps. The results showed the simulations provided a good match to the observed statistics provided by a detailed end use measurement study (Roberts...
This synthesis paper describes the HIV
epidemics in 15 West African countries - Benin, Burkina
Faso, Cote d'Ivoire, Ghana, Guinea, Mali, Niger,
Nigeria, Senegal, Togo, Cape Verde, The Gambia, Guinea
Bissau, Liberia, and Sierra Leone. It focuses particularly
on the degree to which the epidemics in each country are
concentrated or generalized, and the implications for
effective prevention. The urgent need for rigorous analytic
work to equip countries with a sound, situation-specific
analytical base for action motivated this study. The
analysis team critically reviewed and interpreted all
available surveillance, survey and research data (the amount
and quality of which varied considerably by country). For
the first ten countries listed, short country visits enabled
interviews and more thorough search for data and other
information, and the programmatic response to the HIV/AIDS
epidemic was also assessed to develop recommendations for
improving resource allocation and program effectiveness.
The purpose of this modes of
transmission (MoT) study is 'to contribute to the
ongoing efforts to understand the epidemic and response in
Swaziland and thus help the country improve the scope (doing
the right kind of activities), relevance (with the right
populations), and comprehensiveness (reaching all members of
target populations) of Human Immunodeficiency Virus (HIV)
prevention efforts'. The process for the Know Your
Epidemic (KYE) was an in-depth review of available
epidemiological data from Swaziland and the sub-region, and
application of the UNAIDS incidence estimation model. The
aim was to determine the epidemiology of new (incident)
infections. For the Know Your Response (KYR) part, data were
collected on the policy context for prevention, prevention
and prevention activities by implementers, and data from the
National AIDS Spending Assessment (NASA) of 2008 were
reviewed. In a final step, the KYE and KYR evidence was
linked to produce an epidemic, response and policy synthesis
with recommendations to improve the HIV prevention response
through aligning prevention activities with the evidence on
the sources of new infections. The study examined the
hypothesis that multiple...
Pre-natal stress (PNS) or undernutrition can have numerous effects on an individual's biology throughout their lifetime. Some of these effects may be adaptive by allowing individuals to tailor their phenotype to environmental conditions. Here we investigated, in the domestic pig Sus scrofa, whether one possible consequence of a predicted adverse environment could be altered pain perception. The behavioural response of piglets to the surgical amputation (‘docking’) of their tail or a sham procedure was measured for 1 min in piglets born to mothers who either experienced mid-gestation social stress or were left undisturbed throughout pregnancy. A behavioural pain score was found to predict the docked status of piglets with high discriminant accuracy. Piglets exposed to PNS had a significantly higher pain score than controls, and for each litter of tail-docked piglets, the average pain score was correlated with mid-gestation maternal cortisol levels. The data presented here provide evidence that the experience of stress in utero can result in a heightened acute response to injury in early life. Speculatively, this may represent an adaptive alteration occurring as a consequence of a pre-natal ‘early warning’ of environmental adversity.
Background: With the imminent publication of the new edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), there has been a growing interest in the study of the boundaries across the three bulimic spectrum syndromes [bulimia nervosa-purging type (BN-P), bulimia nervosa-non purging type (BN-NP) and binge eating disorder (BED)]. Therefore, the aims of this study were to determine differences in treatment response and dropout rates following Cognitive Behavioural Therapy (CBT) across the three bulimic-spectrum syndromes. Method: The sample comprised of 454 females (87 BED, 327 BN-P and 40 BN-NP) diagnosed according to DSM-IV-TR criteria who were treated with 22 weekly outpatient sessions of group CBT therapy. Patients were assessed before and after treatment using a food and binging/purging diary and some clinical questionnaires in the field of ED. “Full remission” was defined as total absence of binging and purging (laxatives and/or vomiting) behaviors and psychological improvement for at least 4 (consecutive). Results: Full remission rate was found to be significantly higher in BED (69.5%) than in both BN-P (p < 0.005) and BN-NP (p < 0.001), which presented no significant differences between them (30.9% and 35.5%). The rate of dropout from group CBT was also higher in BED (33.7%) than in BN-P (p < 0.001) and BN-NP (p < 0.05)...
The management of dog behavioural problems requires the expertise of professionals such as the veterinary behaviourist. Clinical assessment of behavioural disorders allows the veterinary behaviourist to formulate a diagnosis and prescribe a behavioural and/or pharmacological therapy. The objective of such therapy is to produce a stable change in the perception of a stimulus and the resulting emotion, leading to the correction of the behavioural problem. It may be crucial to evaluate the subject's pathological state in response to the observed symptoms in order to identify the functional impairment of the pivotal neurotransmitter systems involved in the disorder. This allows selecting a suitable pharmacological treatment. In order to implement behavioural therapy, the veterinary behaviourist collaborates, where necessary, with a team of qualified canine trainers.