1,671 research outputs found

    The perceptions of research values and priorities in water resource management from the 3rd Orange River Basin Symposium

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    Research has played an important role in water resource management and a consensus on research objectives would increase the efficiency of these practices. In this paper we aimed to elicit the views of attendees of the 3rd Orange River Basin Symposium regarding water-related research, by using both quantitative and qualitative responses to a questionnairesurvey, and purposeful sampling methods. Overall, research was perceived to play an important role in water resource management and there was significant agreement on which sectors are responsible for carrying out this research. Although clear strengths in water resource management in southern Africa were identified, we found that most perceived weaknessesrelated to the lack of enforcement or to human resource constraints. Despite this fact, the identified research priorities, which were aligned to those of the Water Research Commission, tended to be technical in nature and would not address these perceived weaknesses. Our recommendations were that, by incorporating previously ignored sectors into research,such as private consultants and non-governmental organisations, and addressing human capacity and enforcement issues, unique and unexplored research opportunities could improve water resource management

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    Validation of the Argentine version of the memory binding test (MBT) for early detection of mild cognitive impairment

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    Background: “Forgetfulness” is frequent in normal aging and characteristic of the early stages of dementia syndromes. The episodic memory test is central for detecting amnestic mild cognitive impairment (MCI). The Memory Binding Test (MBT) is a simple, easy and brief memory test to detect the early stage of episodic memory impairment. Objective: To validate the Argentine version of the MBT in a Latin American population and to estimate the diagnostic accuracy as a tool for early detection of MCI. Methods: 88 subjects (46 healthy controls and 42 patients with amnestic MCI) matched for age and educational level were evaluated by an extensive neuropsychological battery and the memory binding test. Results: A significantly better performance was detected in the control group; all MBT scales were predictive of MCI diagnosis (p<.01). The MBT showed high sensitivity (69%) and high specificity (88%), with a PPV of 93% and a NPV of 55% for associative paired recall. A statistically significant difference (χ2=14,164, p<.001) was obtained when comparing the area under the curve (AUC) of the MBT (0.88) and the MMSE (0.70). Conclusion: The Argentine version of the MBT correlated significantly with the MMSE and the memory battery and is a useful tool in the detection of MCI. The operating characteristics of the MBT are well suited, surpassing other tests commonly used for detecting MCI. © 2016, Academia Brasileira de Neurologia. All rights reserved

    Validação da versão argentina do memory binding test (mbt) para a detecção precoce do transtorno cognitivo leve

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    Background: “Forgetfulness” is frequent in normal aging and characteristic of the early stages of dementia syndromes. The episodic memory test is central for detecting amnestic mild cognitive impairment (MCI). The Memory Binding Test (MBT) is a simple, easy and brief memory test to detect the early stage of episodic memory impairment. Objective: To validate the Argentine version of the MBT in a Latin American population and to estimate the diagnostic accuracy as a tool for early detection of MCI. Methods: 88 subjects (46 healthy controls and 42 patients with amnestic MCI) matched for age and educational level were evaluated by an extensive neuropsychological battery and the memory binding test. Results: A significantly better performance was detected in the control group; all MBT scales were predictive of MCI diagnosis (p<.01). The MBT showed high sensitivity (69%) and high specificity (88%), with a PPV of 93% and a NPV of 55% for associative paired recall. A statistically significant difference (c2 =14,164, p<.001) was obtained when comparing the area under the curve (AUC) of the MBT (0.88) and the MMSE (0.70). Conclusion: The Argentine version of the MBT correlated significantly with the MMSE and the memory battery and is a useful tool in the detection of MCI. The operating characteristics of the MBT are well suited, surpassing other tests commonly used for detecting MCI.“Esquecimento” é queixa frequente no envelhecimento normal e também ocorre nos primeiros estágios de síndromes demenciais. Testes de memória episódica são fundamentais para detectar comprometimento cognitivo amnéstico (CCL). O teste de Memória Associativa (Memory Binding Test-MBT) é um teste fácil e breve para detectar a fase inicial de perda de memória episódica. Objetivo: Validar a versão argentina do MBT e estimar a sua acurácia como instrumento diagnóstico para a detecção precoce do CCL. Métodos: 88 indivíduos (46 controles saudáveis e 42 pacientes com CCL amnéstico), emparelhados por idade e nível educacional, foram avaliados com extensa bateria neuropsicológica e o MBT. Resultados: Um desempenho significativamente melhor foi detectada no grupo controle; todas as escalas do MBT foram preditivas do diagnóstico de CCL (p<0,01). O MBT apresentou alta sensibilidade (69%) e alta especificidade (88%), com valor preditivo (VP) positivo de 93% e e VP negativo de 55% para a recordação dos itens associados (associative paired recall). Diferença estatisticamente significativa (c2 =14,164, p<0,001) foi obtida quando foram comparadas as áreas sob as curvas (AUC) do MBT (0,88) e o Mini-Exame do Estado Mental (MEEM) (0,70). Conclusão: A versão argentina do MBT correlacionou-se significativamente com o MEEM e com a bateria de memória e é uma ferramenta útil na detecção de CCL. As características operacionais do MBT são bem adequadas, superando outros testes usualmente utilizados para a detecção de CCL.Fil: Román, Fabián. Gobierno de la Ciudad de Buenos Aires. Hospital "Dr. Abel Zubizarreta"; Argentina. Universidad de la Costa.; ColombiaFil: Iturry, Mónica Liliana. Gobierno de la Ciudad de Buenos Aires. Hospital "Dr. Abel Zubizarreta". Servicio de Neurología. Laboratorio de Investigación de la Memoria; ArgentinaFil: Rojas, Zenón Galeno. Gobierno de la Ciudad de Buenos Aires. Hospital "Dr. Abel Zubizarreta". Servicio de Neurología. Laboratorio de Investigación de la Memoria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barcelo, Ernesto. Universidad de la Costa.; ColombiaFil: Buschke, Herman. Albert Einstein College of Medicine; Estados UnidosFil: Allegri, Ricardo Francisco. Universidad de la Costa.; Colombia. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Sleep abnormalities in progressive supranuclear palsy

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    We studied sleep patterns for three nights in 10 subjects with moderate to severe progressive supranuclear palsy and correlated the findings with disease severity using quantitative measures of motor, cognitive, and eye movement impairment. All subjects had severe insomnia, spending 2 to 6 hours awake per night; the mean time awake per night for the group was more than 4 hours. Sleep latency became shorter and the number of awakenings increased with greater motor impairment, and total sleep time declined as dementia worsened. These findings indicate that in progressive supranuclear palsy insomnia is related to disease severity. Insomnia associated with progressive supranuclear palsy appears to be worse than the insomnia of Parkinson's disease or Alzheimer's disease and may be due to degenerative changes in brain structures responsible for sleep maintenance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50331/1/410250609_ftp.pd

    Increased Risk of Mortality in Alzheimer's Disease Patients with More Advanced Educational and Occupational Attainment

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    A reserve hypothesis suggests that clinical symptoms of Alzheimer's disease (AD) begin earlier in individuals with less education. Therefore, patients with less education might survive longer after diagnosis than those with more education. Two hundred forty-six subjects with probable AD were following for 1 to 4 years. There were 78 deaths; 30 deaths occurred in the 127 patients whose education was ≤8 years, while 48 deaths occured in the 119 patients with <8 years of education. Cox proportional hazards models adjusted for age, gender, and clinical dementia rating (CDR) showed that patients with more education had increased mortality (continuous variable: RR = 1.06 for each years of education; 95% confidence interval {CI}, 1.01-1.11; dichotomous variable at 8 yr: RR = 1.76; CI, 1.11-2.77). This observation might at first seem counterintuitve, since groups with lower socioeconomic status are often at greater mortality risk. It implies that at any level of assessed clinical severity, the underlying pathology of AD is more advanced in patients with more education, resulting in shorter duration of diagnosed disease before death. These findings suggest either that education systematically influences global ratings of disease severity or that education provides a reserve against the clinical manifestation of AD pathology

    Effects of Oral Physostigmine in Alzheimer's Disease

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    Previous studies of oral physostigmine in the treatment of Alzheimer's disease have: (1) assumed physostigmine is effective only in mildly affected patients; (2) relied on an initial “dose-finding” phase to determine the most effective dose and excluded nonresponders; and (3) primarily assessed memory. We examined the response of 22 patients to six different daily dosages of oral physostigmine, using selective reminding tests that were administered twice daily. Nine patients had a “best” dose/day (mode = 13 mg/day), which was used in a subsequent double-blind crossover study. The otehr 13 were given the highest tolerated dose. The selective reminding test and a full neuropsychological battery were given during the drug and placebo periods. As a group, the 22 patients improved significantly on the Wechsler Adult Intelligence Scale—Revised Digit Symbol subtest and a shape cancelation task (p < 0.05). Nine patients showed improved performance on the selective reminding test during physostigmine treatment, and 9 showed no response; 4 patients performed better during placebo treatment. Dose finding did not help in predicting response in the crossover study; only 2 of the 9 who showed improvement had a best dose. Dementia severity did not predict corssover response. This suggests that: (1) physostigmine as administered had no pronounced effect on memory in Alzheimer's disease; (2) oral physostigmine produces no greater benefits on memory in mildly than in moderately demented patients; (3) response in a dose-finding phase does not predict response in double-blind crossover; and (4) Digit Symbol and cancelation tasks may be more sensitive than memory tests to the effects of oral physostigmine

    Adverse performance effects of acute lorazepam administration in elderly long-term users: pharmacokinetic and clinical predictors.

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    BACKGROUND: The benzodiazepine lorazepam is widely utilized in the treatment of elderly individuals with anxiety disorders and related conditions. Negative effects of acute lorazepam administration on cognitive performance, especially memory, have been reported in both previously untreated elderly and in individuals who have received short term (up to three weeks) treatment with therapeutic doses. However, it remains unclear if these adverse cognitive effects also persist after long-term use, which is frequently found in clinical practice. METHODS: Cognitively intact elderly individuals (n=37) on long-term (at least three months) daily treatment with lorazepam were studied using a double-blind placebo-controlled cross-over study design. Subjects were administered their highest daily unit dose of lorazepam (0.25-3.00 mg) or placebo on different days, approximately 1 week apart in a random order, and were assessed on memory, psychomotor speed, and subjective mood states. RESULTS: Subjects had significantly poorer recall and slowed psychomotor performance following acute lorazepam administration. There were no significant effects on self-ratings of mood, sedation, or anxiety in the whole group, but secondary analyses suggested a differential response in subjects with Generalized Anxiety Disorder. CONCLUSIONS: The reduced recall and psychomotor slowing that we observed, along with an absence of significant therapeutic benefits, following acute lorazepam administration in elderly long-term users reinforces the importance of cognitive toxicity as a clinical factor in benzodiazepine use, especially in this population

    Random population fluctuations bias the Living Planet Index

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    The Living Planet Index (LPI) is a standardized indicator for tracking population trends through time. Due to its ability to aggregate many time series in a single metric, the LPI has been proposed as an indicator for the Convention on Biological Diversity’s post-2020 Global Biodiversity Strategy. However, here we show that random population fluctuations introduce biases when calculating the LPI. By combining simulated and empirical data, we show how random fluctuations lead to a declining LPI even when overall population trends are stable and imprecise estimates of the LPI when populations increase or decrease nonlinearly. We applied randomization null models that demonstrate how random fluctuations exaggerate declines in the global LPI by 9.6%. Our results confirm substantial declines in the LPI but highlight sources of uncertainty in quantitative estimates. Randomization null models are useful for presenting uncertainty around indicators of progress towards international biodiversity targets.DATA AVAILABILITY: Empirical data of population time series in the Living Planet database are available from the dedicated website maintained by the Zoological Society of London (ZSL) (http://stats.livingplanetindex.org/) and are subject to the Data Use Policy by the Indicators & Assessments Unit at the ZSL and WWF International. Simulated data to replicate the results are available from https://doi.org/10.5281/zenodo.4744533.CODE AVAILABILITY : All simulation outputs and code (R scripts) to reproduce the results in this manuscript are available from https://doi.org/10.5281/zenodo.4744533.EXTENDED DATA FIG. 1: The nine steps to calculating the Living Planet Index (LPI).EXTENDED DATA FIG. 2: The Living Planet Index (LPI) for randomly fluctuating populations that are stable on average.EXTENDED DATA FIG. 3: Starting population sizes of time series added to the Living Planet Index have declined between 1950 and 2015.EXTENDED DATA FIG. 4: Larger population fluctuations cause less precise estimates of the Living Planet Index (LPI) in nonlinear population trajectories.EXTENDED DATA FIG 5: Population fluctuations cause generalised additive models (GAM) to misestimate starting and ending populations when populations decrease from 100 to 40 individuals.EXTENDED DATA FIG 6: Population fluctuations cause generalised additive models (GAM) to misestimate starting and ending populations when populations increase from 100 to 160 individuals.EXTENDED DATA FIG 7: The reshuffling null model used to account for random population fluctuations.EXTENDED DATA FIG. 8: Cumulative population declines can occur in the Living Planet Index even when average population declines are zero.EXTENDED DATA FIG. 9: Cumulative population changes represent empirical trajectories more accurately than average changes as time series lengths increase.The National Research Foundation of South Africa and the Jennifer Ward Oppenheimer Research Grant.https://www.nature.com/natecolevolhj2022Zoology and Entomolog
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