Robust spectrotemporal decomposition by iteratively reweighted least squares

Classical nonparametric spectral analysis uses sliding windows to capture the dynamic nature of most real-world time series. This universally accepted approach fails to exploit the temporal continuity in the data and is not well-suited for signals with highly structured time–frequency representations. For a time series whose time-varying mean is the superposition of a small number of oscillatory components, we formulate nonparametric batch spectral analysis as a Bayesian estimation problem. We introduce prior distributions on the time–frequency plane that yield maximum a posteriori (MAP) spectral estimates that are continuous in time yet sparse in frequency. Our spectral decomposition procedure, termed spectrotemporal pursuit, can be efficiently computed using an iteratively reweighted least-squares algorithm and scales well with typical data lengths. We show that spectrotemporal pursuit works by applying to the time series a set of data-derived filters. Using a link between Gaussian mixture models, ℓ[subscript 1] minimization, and the expectation–maximization algorithm, we prove that spectrotemporal pursuit converges to the global MAP estimate. We illustrate our technique on simulated and real human EEG data as well as on human neural spiking activity recorded during loss of consciousness induced by the anesthetic propofol. For the EEG data, our technique yields significantly denoised spectral estimates that have significantly higher time and frequency resolution than multitaper spectral estimates. For the neural spiking data, we obtain a new spectral representation of neuronal firing rates. Spectrotemporal pursuit offers a robust spectral decomposition framework that is a principled alternative to existing methods for decomposing time series into a small number of smooth oscillatory components.National Institutes of Health (U.S.) (Transformative Research Award GM 104948)National Institutes of Health (U.S.) (New Innovator Award R01-EB006385

Lutte contre Glossina fuscipes fuscipes par piégeage chez les éleveurs Mbororo de République Centrafricaine

Le "glissement" historique des éleveurs Mbororo d'ouest en est s'accélère sous divers facteurs, dont la sécheresse, et les pousse à s'installer plus loin et plus durablement dans les savanes humides infestées de glossines. Pour limiter l'usage important des trypanocides et trypanopréventifs dans une "zone d'action agropastorale" en création en RCA, un essai de lutte contre Glossina fuscipes fuscipes est mis en place par piépeage ponctuel à l'aide de deux pièges biconiques classiques (non imprégnés d'insecticide), installés à chaque abreuvoir (deux abreuvoirs par campement) dans 32 campements d'éleveurs sédentaires en saison des pluies et plus ou moins transhumants en saison sèche. L'éleveur collecte lui-même les glossines prises et surveille le bon état des pièges. Les réductions de densité apparente sont très fortes après un mois et en général supérieures à 90 p. 100 après deux mois. Elles sont plus rapides et homogènes en saison sèche qu'en saison des pluies. Dans cet essai, les éleveurs ont bien géré leurs pièges. Ils sont motivés et demandeurs de cette technique simple de lutte. Le problème de son application en milieu semi-sédentaire est posé. L'information et la formation données aux éleveurs devra s'intensifier par divers moyens (fiche technique, montage audiovisuel, stages

Lutte contre Glossina fuscipes fuscipes par piégeage chez les éleveurs Mbororo de République Centrafricaine

Le "glissement" historique des éleveurs Mbororo d'ouest en est s'accélère sous divers facteurs, dont la sécheresse, et les pousse à s'installer plus loin et plus durablement dans les savanes humides infestées de glossines. Pour limiter l'usage important des trypanocides et trypanopréventifs dans une "zone d'action agropastorale" en création en RCA, un essai de lutte contre Glossina fuscipes fuscipes est mis en place par piépeage ponctuel à l'aide de deux pièges biconiques classiques (non imprégnés d'insecticide), installés à chaque abreuvoir (deux abreuvoirs par campement) dans 32 campements d'éleveurs sédentaires en saison des pluies et plus ou moins transhumants en saison sèche. L'éleveur collecte lui-même les glossines prises et surveille le bon état des pièges. Les réductions de densité apparente sont très fortes après un mois et en général supérieures à 90 p. 100 après deux mois. Elles sont plus rapides et homogènes en saison sèche qu'en saison des pluies. Dans cet essai, les éleveurs ont bien géré leurs pièges. Ils sont motivés et demandeurs de cette technique simple de lutte. Le problème de son application en milieu semi-sédentaire est posé. L'information et la formation données aux éleveurs devra s'intensifier par divers moyens (fiche technique, montage audiovisuel, stages

Physostigmine and Methylphenidate Induce Distinct Arousal States During Isoflurane General Anesthesia in Rats

BACKGROUND: Although emergence from general anesthesia is clinically treated as a passive process driven by the pharmacokinetics of drug clearance, agents that hasten recovery from general anesthesia may be useful for treating delayed emergence, emergence delirium, and postoperative cognitive dysfunction. Activation of central monoaminergic neurotransmission with methylphenidate has been shown to induce reanimation (active emergence) from general anesthesia. Cholinergic neurons in the brainstem and basal forebrain are also known to promote arousal. The objective of this study was to test the hypothesis that physostigmine, a centrally acting cholinesterase inhibitor, induces reanimation from isoflurane anesthesia in adult rats. METHODS: The dose-dependent effects of physostigmine on time to emergence from a standardized isoflurane general anesthetic were tested. It was then determined whether physostigmine restores righting during continuous isoflurane anesthesia. In a separate group of rats with implanted extradural electrodes, physostigmine was administered during continuous inhalation of 1.0% isoflurane, and the electroencephalogram changes were recorded. Finally, 2.0% isoflurane was used to induce burst suppression, and the effects of physostigmine and methylphenidate on burst suppression probability (BSP) were tested. RESULTS: Physostigmine delayed time to emergence from isoflurane anesthesia at doses ≥0.2 mg/kg (n = 9). During continuous isoflurane anesthesia (0.9% ± 0.1%), physostigmine did not restore righting (n = 9). Blocking the peripheral side effects of physostigmine with the coadministration of glycopyrrolate (a muscarinic antagonist that does not cross the blood-brain barrier) produced similar results (n = 9 each). However, during inhalation of 1.0% isoflurane, physostigmine shifted peak electroencephalogram power from δ ( < 4 Hz) to θ (4-8 Hz) in 6 of 6 rats. During continuous 2.0% isoflurane anesthesia, physostigmine induced large, statistically significant decreases in BSP in 6 of 6 rats, whereas methylphenidate did not. CONCLUSIONS: Unlike methylphenidate, physostigmine does not accelerate time to emergence from isoflurane anesthesia and does not restore righting during continuous isoflurane anesthesia. However, physostigmine consistently decreases BSP during deep isoflurane anesthesia, whereas methylphenidate does not. These findings suggest that activation of cholinergic neurotransmission during isoflurane anesthesia produces arousal states that are distinct from those induced by monoaminergic activation.National Institutes of Health (U.S.) (Grant TR01-GM104948)National Institutes of Health (U.S.) (Grant DP1-OD003646)National Institutes of Health (U.S.) (Grant K08-GM094394

Impact of personality traits on work performance in tidal paddy production in the Gambia: a review

Efficient personality is central for effective work performance in tidal paddy farming. Improve rice productivity in the Gambia is essential for stakeholders as it is main actor in achieving food self-sufficiency and security. The aim of this paper is to confirm the impact of personality traits on work performance. Furthermore, to determine the relation between the personality traits for the paddy farmers with work performance; and also to identify the strength of the traits relation with work performance for paddy farmers. This paper uses previous works on personality traits, work performance, and its related studies and looked at how the seven personality traits (willingness to take risks, information seekers, problem solving ability, willingness to spend on capital, extensive network of information, dare to make decisions, and highly disciplined) of paddy farmers and work performance can be used to boost urban food supply through rice production. The need for appropriate development programs is required as one of the options to generate income and improve livelihood of farmers in developing countries

Kinetics and Equilibrium Study for the Adsorption of Maxilon Blue Dye on Prosopis juliflora Fruit Seeds as a Low-Cost Adsorbent

The aim of this work was to investigate the adsorption capacity of Maxilon Blue dye using Prosopis juliflora fruit seeds as an adsorbent. The seeds of P. Juliflora were utilized as a low-cost adsorbent to remove the cationic dye, Maxilon Blue, from an aqueous solution in batch experiments, examining the effects of mass, pH, and contact time. Three error functions —coefficient of determination, Chi-square, and the sum of error squares — were employed to assess the adsorption data. The adsorption equilibrium was characterized using Langmuir, Freundlich, and Temkin isotherm models. The equilibrium data closely followed the Langmuir model, indicating a maximum adsorption capacity of 85.54 mg/g on a monolayer. To elucidate the adsorption mechanisms, pseudo-first-order and pseudo-second-order kinetic models were applied. The kinetic analysis revealed that the adsorption process conformed best to the pseudo-second-order model. Consequently, this study demonstrates that P. juliflora fruit seeds are an effective, economical, and eco-friendly adsorbent for the removal of Maxilon Blue dye from aqueous solutions

Gendering Technologies: Women In Cameroons Pink-Collar ICT Work

This paper examines the rise of low-skilled, low-paying, female dominated jobs in Cameroons information and communication technology (ICT) sector. It seeks to understand why and how women (mostly between the ages of 18 and 35) seem to be naturally drawn to these jobs, described in the literature as pink-collar jobs. Through interviews with ICT workers and observations at ICT training centers and call centers in Buea, a major city in the Southwest Region of Cameroon, the paper explores the factors that hinder womens entry into more technical ICT jobs in Cameroon. It concludes that some of these factors, such as the prior income level of female ICT workers and the absence of female instructors at ICT training centers, further reinforce gender-based job classifications and the rise of ghettoization in Cameroons ICT sector

Pharyngeal Carriage of Beta-Haemolytic Streptococcus Species and Seroprevalence of Anti-Streptococcal Antibodies in Children in Bouaké, Côte d’Ivoire

The pharynx of the child may serve as a reservoir of pathogenic bacteria, including beta-haemolytic group A streptococci (GAS), which can give rise to upper airway infections and post-streptococcal diseases. The objective of this study was to determine the prevalence of beta-haemolytic Streptococcus spp. in pharyngeal samples stemming from children aged 3–14 years in Bouaké, central Côte d’Ivoire. Oropharyngeal throat swabs for microbiological culture and venous blood samples to determine the seroprevalence of antistreptolysin O antibodies (ASO) were obtained from 400 children in March 2017. Identification was carried out using conventional bacteriological methods. Serogrouping was performed with a latex agglutination test, while an immunological agglutination assay was employed for ASO titres. The mean age of participating children was 9 years (standard deviation 2.5 years). In total, we detected 190 bacteria in culture, with 109 beta-haemolytic Streptococcus isolates, resulting in an oropharyngeal carriage rate of 27.2%. Group C streptococci accounted for 82.6% of all isolates, whereas GAS were rarely found (4.6%). The ASO seroprevalence was 17.3%. There was no correlation between serology and prevalence of streptococci (p = 0.722). In conclusion, there is a high pharyngeal carriage rate of non-GAS strains in children from Bouaké, warranting further investigation