16 research outputs found
Co-occurrence of schizophrenia and obsessive compulsive disorder - A literature review
No Abstract
The influence of animal traits on feedlot profitability of Santa Gertrudis cattle in South Africa
Effects of current CO2 assimilation and stored reserves on lychee fruit growth
The roles of current CO2 assimilation and stored carbohydrates on fruit retention in lychee (Litchi chinensis Sonn.) were investigated. In 12 year old âTai Soâ trees growing at Burgershall in subtropical South Africa (lat. 25°S), terminal branches were cinctured (girdled) 0.5 or 1.0 m from the fruit cluster about 2â4 weeks after anthesis in October to isolate the fruit from the rest of the tree. Each branch had 0, 5,10, 20 or 30 leaves, and 0, 5,10, 20 or 30 fruit. In a separate experiment, branches were cinctured 0.5 or 1.5 m from the fruit cluster in October, while uncinctured branches acted as controls. At Nambour in subtropical Australia (lat. 27°S), branches of ten year old âSouey Tungâ were cinctured in October after fruit set about 1.2 m from the fruit cluster, while other branches were cinctured and thinned to five leaves or five fruit per fruit cluster or left uncinctured and unthinned. In other experiments, seven year old trees of cv. Wai Chee and ten year old trees of cv. Kwai May Pink were cinctured on the trunk in November or left uncinctured. The number of fruit retained per panicle, net CO2 assimilation, yield and concentrations of starch in the leaves and stem were determined. In South Africa, the greatest number of fruit per panicle at harvest (8.6) occurred with 30 leaves and 30 fruit at the start of sampling, but a different response was given when the number of fruit retained was expressed as a proportion of that soon after fruit set. Relative fruit retention was below 5% in branches with no leaves and 50â60% in branches with six leaves per fruit. In Australia, about a quarter of the fruit were retained at harvest in control and cinctured branches compared with more than two-thirds after fruit thinning and only one-tenth after leaf thinning. Starch generally accumulated in the stems after fruit were removed, whereas CO2 assimilation was greatest after leaf removal and least with fruit removal. There was double the relative fruit retention with cinctures at 0.5 m (25%) compared with controls (14%), and three times as many with cinctures at 1.5 m (38%), and a 35% increase in yield when whole trees were cinctured. These results suggest that lychee fruit appear to be mainly dependent on current CO2 assimilation. Cincturing increased yields presumably by redirecting assimilates to the developing crop
A dynamic flotation model to infer process characteristics from online measurements
A dynamic flotation model incorporating fundamental and phenomenological relationships, information from froth images and steady-state models is described. Model outputs correspond with online measurements commonly available on flotation circuits, and the model parameters are estimated from industrial data. Simulation results are presented, highlighting important non-linearities that need to be taken into account for optimal flotation operation. Observability and controllability analyses are performed, proving that key flotation parameters can theoretically be estimated from online process measurements, and that the set of modelled inputs can control all the model outputs. This model can be used in advanced model-based control and optimisation applications. The ability to estimate key flotation parameters opens up opportunities for improved optimisation of operating variables such as aeration rates, froth depth and the reagent recipe.The National Research Foundation of South Africa.https://www.elsevier.com/locate/minenghj2022Electrical, Electronic and Computer Engineerin
Depressive and anxiety symptoms in patients with schizophrenia and schizophreniform disorder
Background: Symptoms of depression and anxiety are frequently encountered in the course of schizophrenia and are of considerable clinical importance. They may compromise social and vocational functioning, and they are associated with an increased risk of relapse and suicide. Various treatment approaches have been reported to be successful. Method: The sample comprised 177 patients with DSM-III-R or DSM-IV schizophrenia or schizophreniform disorder who were participants in multinational clinical drug trials at our academic psychiatric unit over a 7-year period and who were assessed by means of the Positive and Negative Syndrome Scale (PANSS). Analysis was performed on baseline PANSS scores. The depression/anxiety score was compared in the men and women, first-episode and multiple-episode patients, and those with predominantly positive and negative syndromes. Correlations were sought between depression/anxiety scores and age, total PANSS score, positive score, negative score, general psychopathology score, and treatment outcome. Multivariate analysis was applied to determine contributions of individual variables toward depression/anxiety and outcome scores. Results: Depression and anxiety symptoms were more severe in women (p = .007), first-episode patients (p = .02), and those with predominantly positive symptoms (p < .0001). Depression/anxiety scores were significantly correlated to age (r =-0.31, p < .0001), PANSS positive scores (r = 0.39, p < .0001), and treatment outcome (r = 0.25, p = .006). Multivariate analysis bore out these results, with the exception that first episode was not a significant predictor of depression and anxiety scores. Conclusion: PANSS depressive/anxiety scores were generally low in our sample, perhaps because patients with schizoaffective disorder were excluded. The finding that these symptoms were more prominent in women and first-episode patients is in keeping with previous literature. The higher scores in first-episode patients are likely due to the higher positive symptom scores in these patients. The association between depressive/anxiety scores and positive symptoms but not with negative symptoms points to a specific relationship between affective symptoms and the positive symptom domain of schizophrenia. The presence of depressive and anxiety symptoms may predict a more favorable outcome to treatment, although this may only apply to the acute exacerbations of the illness.Articl
A survey on the status of industrial flotation control
A survey was conducted to establish the status-quo of industrial flotation control.
The survey focussed on the measurements and actuators generally available in industry, the
reliability and accuracy of measurements, and how important process variables are controlled. It
is evident from the survey that regulatory control is well established with reliable and relatively
accurate measurements available throughout a plant. The introduction of froth image analysers
seems to gain good traction and enables improved control of mass pull to achieve consistent
concentrate grade. Although supervisory control may soon be the new standard for flotation
plants, on-line grade optimisation requires further work.https://www.journals.elsevier.com/ifac-papersonlinepm2021Electrical, Electronic and Computer Engineerin
NcuropsychiatryofHypersexuality
Relatively few studies of the psychobiology ofhyperscxuality have been undertaken. Nevertheless, the literature does suggest the possibility of a neurobiology ofhypersexuality. Three cases of hypersexual behavior are presented in the context of neuropsychiatrie disorders, and the literature on this phenomenon is briefly reviewed. These case studies and the literature provide evidence that different brain.systems may play a role in this disorder. Frontal lesions may be accompanied by disinhibition, including impulsive hypersexual response to external cues, ivhile striatal lesions may be accompanied by repetitive triggering of internally generated response patterns. Temporal-limbic lesions may be accompanied by disturbances in sexual appetite itself, including change in the direction of sexual drive. These case studies demonstrate that a neurobiology ofhypersexuality may prove of some heuristic value in the clinic. However, further research is required to consolidate the literature in this area.Articl
Ethnicity and treatment response in schizophrenia: A comparison of 3 ethnic groups
Background: Numerous cultural and ethnic factors may directly and indirectly influence treatment outcome in schizophrenia. The present study compared the response to antipsychotic treatment in 3 ethnic groups of patients with schizophrenia. Method: Fifty black, 63 mixed descent, and 79 white patients with DSM-IV-diagnosed schizophrenia or schizophreniform disorder who were participants in multinational clinical drug trials were assessed by means of the Positive and Negative Syndrome Scale (PANSS). Treatment response was measured by the change in PANSS total scores and the change in positive, negative, and general psychopathology subscale scores from baseline to 6 weeks. Also, the percentage of responders (defined as ℠40% reduction in PANSS total scores) was calculated for each group. Results: Baseline PANSS scores differed significantly, being higher for black and mixed descent patients. Mixed descent patients showed the greatest mean ± SD percentage reduction in PANSS total score (29.4 ± 21.6) followed by black (28.4 ± 14.7) and white (11.4 ± 27.6) patients. Analysis of covariance revealed a significant effect of ethnicity on the reduction in PANSS total scores (p < .0001). The numbers of responders were 20 mixed descent (32%), 12 black (24%), and 7 white (9%) patients (p = .002). Conclusion: Significant ethnic differences in acute antipsychotic treatment response are demonstrated by this study. Factors such as diet, nutritional status, body mass, and substance use could be important, as well as genetically determined ethnospecific pharmacokinetic and pharmacodynamic differences. Delayed help-seeking may account for the higher baseline scores in the black and mixed descent patients.Articl
The factor structure for positive and negative symptoms in South African Xhosa patients with schizophrenia
Most studies investigating the symptom dimensions of schizophrenia utilising the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS) favour a three factor model. This study sought to investigate the factor structure of both the global and individual items of the SANS and SAPS in a large sample of South African Xhosa patients with schizophrenia. A total of 422 subjects participated. Both principal components and factor analytical procedures were applied. For the global items, a two-factor solution representing positive and negative symptoms accounted for 59.9% of the variance. Alternatively, the three-dimensional model of negative, psychotic and disorganisation factors was supported by a five-factor solution if the more heterogeneous items of attention and alogia were ignored. Analysis of the individual items yielded a five-factor solution with the negative symptoms splitting into diminished expression and disordered relating, and the positive symptoms separating into factors for psychosis, thought disorder and bizarre behaviour. Our findings are very similar to those from other parts of the world, providing evidence that the factor structure for the symptoms of schizophrenia is relatively resistant to cultural influences. This is particularly true for negative symptoms. © 2001 Elsevier Science B.V.Articl
Let's play: Me and my AIâpowered avatar as one team
Artificial intelligence (AI) tools have altered the gaming industry, thanks to their newly incepted functionalities, which have enhanced the consumer experience. Building on innovation diffusion theory, technology acceptance model, and flow theory, this study highlights an AIâpowered avatar concept. This study explores the roles of perceived easiness, usefulness, advantage, compatibility, enjoyment, customization, and interactivity in forming the gamers' intention to play with AIâpowered avatars. A survey data of 500 respondents from China having experience playing online video games is used to test the proposed hypotheses. The results offer significant support to the proposed relationships related to adopting an AIâpowered avatar and the consumers' psychological association with its adoption. Consequently, the results imply that AIâpowered avatars should allow gamers to customize, interact, and take assistance to move up levels with an enjoyable experience. Moreover, this study also suggests that digital technologies such as AI could be integrated into the gaming environment for a more pleasing and immersive experience