Web-enabled Intelligent System for Continuous Sensor Data Processing and Visualization

A large number of sensors deployed in recent years in various setups and their data is readily available in dedicated databases or in the cloud. Of particular interest is real-time data processing and 3D visualization in web-based user interfaces that facilitate spatial information understanding and sharing, hence helping the decision making process for all the parties involved. In this research, we provide a prototype system for near real-time, continuous X3D-based visualization of processed sensor data for two significant applications: thermal monitoring for residential/commercial buildings and nitrogen cycle monitoring in water beds for aquaponics systems. As sensors are sparsely placed, in each application, where they collect data for large periods (of up to one year), we employ a Finite Differences Method and a Neural Networks model to approximate data distribution in the entire volume

The prevalence and clinical profile of adrenocortical deficiency among HIV infected persons in Northern Nigeria

Background: Infection with the human immune deficiency virus (HIV) is still a prevalent problem in Africa.Objectives: The aim of this study was to determine the prevalence of hypocortisolism among patients with HIV and their clinical profile at Aminu Kano Teaching Hospital (AKTH), Kano, Nigeria.Method: Three hundred and fifty adult patients with HIV infection were recruited from the HIV clinic of AKTH, Kano. Blood samples for serum electrolytes, and cortisol both before and after the short Synacthen test were taken for estimation. Data were analyzed using the SPSS version 20.0 software.Results: One hundred and eight (30.9%) of participants had low baseline serum cortisol levels, while 57 (16.3%) had a low serum cortisol after short synacthen test. There was no significant relationship between the cortisol levels and clinical features of hypocortisolism, WHO clinical stage of HIV, hypernatremia or HAART regimen. There was a negative correlation between the stimulated serum cortisol and duration of diagnosis of HIV, participants BMI and CD4 counts.Conclusion: The biochemical evidence of hypocortisolism was common among patients infected with HIV, associated with a longer duration of HIV infection. However, none of CD4 counts, clinical features or HAART regimen were associated with hypocortisolism.Keywords: Hypocortisolism, HIV infection, short Synacthen test

Correlated Markov Quantum Walks

We consider the discrete time unitary dynamics given by a quantum walk on $\Z^d$ performed by a particle with internal degree of freedom, called coin state, according to the following iterated rule: a unitary update of the coin state takes place, followed by a shift on the lattice, conditioned on the coin state of the particle. We study the large time behavior of the quantum mechanical probability distribution of the position observable in $\Z^d$ for random updates of the coin states of the following form. The random sequences of unitary updates are given by a site dependent function of a Markov chain in time, with the following properties: on each site, they share the same stationnary Markovian distribution and, for each fixed time, they form a deterministic periodic pattern on the lattice. We prove a Feynman-Kac formula to express the characteristic function of the averaged distribution over the randomness at time $n$ in terms of the nth power of an operator $M$. By analyzing the spectrum of $M$, we show that this distribution posesses a drift proportional to the time and its centered counterpart displays a diffusive behavior with a diffusion matrix we compute. Moderate and large deviations principles are also proven to hold for the averaged distribution and the limit of the suitably rescaled corresponding characteristic function is shown to satisfy a diffusion equation. An example of random updates for which the analysis of the distribution can be performed without averaging is worked out. The random distribution displays a deterministic drift proportional to time and its centered counterpart gives rise to a random diffusion matrix whose law we compute. We complete the picture by presenting an uncorrelated example.Comment: 37 pages. arXiv admin note: substantial text overlap with arXiv:1010.400

Random Time-Dependent Quantum Walks

We consider the discrete time unitary dynamics given by a quantum walk on the lattice $\Z^d$ performed by a quantum particle with internal degree of freedom, called coin state, according to the following iterated rule: a unitary update of the coin state takes place, followed by a shift on the lattice, conditioned on the coin state of the particle. We study the large time behavior of the quantum mechanical probability distribution of the position observable in $\Z^d$ when the sequence of unitary updates is given by an i.i.d. sequence of random matrices. When averaged over the randomness, this distribution is shown to display a drift proportional to the time and its centered counterpart is shown to display a diffusive behavior with a diffusion matrix we compute. A moderate deviation principle is also proven to hold for the averaged distribution and the limit of the suitably rescaled corresponding characteristic function is shown to satisfy a diffusion equation. A generalization to unitary updates distributed according to a Markov process is also provided. An example of i.i.d. random updates for which the analysis of the distribution can be performed without averaging is worked out. The distribution also displays a deterministic drift proportional to time and its centered counterpart gives rise to a random diffusion matrix whose law we compute. A large deviation principle is shown to hold for this example. We finally show that, in general, the expectation of the random diffusion matrix equals the diffusion matrix of the averaged distribution.Comment: Typos and minor errors corrected. To appear In Communications in Mathematical Physic

Occurrence of hypocortisolism in HIV patients: Is the picture changing?

Background: The occurrence of endocrine diseases in people who are infected with HIV is traditionally thought to occur in the setting of AIDS with opportunistic infections and malignancies. However, recent studies find the correlation between hypocortisolism and stage of HIV (CD4 count and WHO clinical stage) inconsistent.Methods: This descriptive cross-sectional study included three hundred and fifty (350) consecutive patients with HIV infection. They were interviewed, and subsequently underwent laboratory evaluation for the detection of hypocortisolism. Blood samples for serum cortisol estimation were taken at baseline and at 30 minutes following the administration of 1μg of tetracosactrin (Synacthen). In addition, the patients had blood samples taken at 0 minutes (baseline) for CD4+ lymphocyte cell counts.Results: At baseline, 108 (30.9%) participants had serum cortisol levels below 100 μg/L with a median value of 55.48 μg/L (11.36-99.96 μg/L), but only 57 (16.3%) study participants had stimulated serum cortisol levels below 180 μg/L with median of 118 μg/L (19.43-179.62). There was no significant difference in the occurrence of clinical features between participants with low and normal serum cortisol, nor WHO clinical stage, CD4 count and ART regimen. The occurrence of hypocortisolism was higher among participants who had been on ART for a longer period of time.Conclusion: There is a high prevalence of hypocortisolism among HIV patients by biochemical testing, especially those who have been on ARVs for a longer duration. Hypocortisolism cannot be predicted based on the participants’ WHO clinical stage of disease, CD4 cell count, or the treatment regimen.  Funding: Personal FundsKeywords: HIV, Adrenocortical insufficiency, CD4 cell count, Tetracosactri

Attention Patterns Detection using Brain Computer Interfaces

The human brain provides a range of functions such as expressing emotions, controlling the rate of breathing, etc., and its study has attracted the interest of scientists for many years. As machine learning models become more sophisticated, and bio-metric data becomes more readily available through new non-invasive technologies, it becomes increasingly possible to gain access to interesting biometric data that could revolutionize Human-Computer Interaction. In this research, we propose a method to assess and quantify human attention levels and their effects on learning. In our study, we employ a brain computer interface (BCI) capable of detecting brain wave activity and displaying the corresponding electroencephalograms (EEG). We train recurrent neural networks (RNNS) to identify the type of activity an individual is performing

PM3 and DFT Computational Studies of the Reaction Mechanism of Formaldehyde and Isoleucine

The reaction of formaldehyde and Isoleucine was studied using semi-empirical and density functional theory methods. Possible reactive sites are proposed and reaction mechanism postulated. It was found that the Isoleucine nitrogen attacks the carbonyl carbon of formaldehyde and forms a methylol intermediate that undergoes a condensation with another Isoleucine to produce a Methylenediisoleucine through a methylene bridge (cross-linking). The enthalpies of the reaction are -78.79 kJ/mol and -39.14kJ/mol for PM3 and DFT respectively also ΔSo and ΔGo, for the PM3 and DFT studies predicted. The reaction was found to be exothermic and second order

Statistical properties of power-law random banded unitary matrices in the delocalization-localization transition regime

Power-law random banded unitary matrices (PRBUM), whose matrix elements decay in a power-law fashion, were recently proposed to model the critical statistics of the Floquet eigenstates of periodically driven quantum systems. In this work, we numerically study in detail the statistical properties of PRBUM ensembles in the delocalization-localization transition regime. In particular, implications of the delocalization-localization transition for the fractal dimension of the eigenvectors, for the distribution function of the eigenvector components, and for the nearest neighbor spacing statistics of the eigenphases are examined. On the one hand, our results further indicate that a PRBUM ensemble can serve as a unitary analog of the power-law random Hermitian matrix model for Anderson transition. On the other hand, some statistical features unseen before are found from PRBUM. For example, the dependence of the fractal dimension of the eigenvectors of PRBUM upon one ensemble parameter displays features that are quite different from that for the power-law random Hermitian matrix model. Furthermore, in the time-reversal symmetric case the nearest neighbor spacing distribution of PRBUM eigenphases is found to obey a semi-Poisson distribution for a broad range, but display an anomalous level repulsion in the absence of time-reversal symmetry.Comment: 10 pages + 13 fig

A Review of Ground Target Detection and Classification Techniques in Forward Scattering Radars

This paper presents a review of target detection and classification in forward scattering radar (FSR) which is a special state of bistatic radars, designed to detect and track moving targets in the narrow region along the transmitter-receiver base line. FSR has advantages and incredible features over other types of radar configurations. All previous studies proved that FSR can be used as an alternative system for ground target detection and classification. The radar and FSR fundamentals were addressed and classification algorithms and techniques were debated. On the other hand, the current and future applications and the limitations of FSR were discussed

The prevalence and clinical profile of adrenocortical deficiency among HIV infected persons in Northern Nigeria

Background: Infection with the human immune deficiency virus (HIV) is still a prevalent problem in Africa. Objectives: The aim of this study was to determine the prevalence of hypocortisolism among patients with HIV and their clinical profile at Aminu Kano Teaching Hospital (AKTH), Kano, Nigeria. Method: Three hundred and fifty adult patients with HIV infection were recruited from the HIV clinic of AKTH, Kano. Blood samples for serum electrolytes, and cortisol both before and after the short Synacthen test were taken for estimation. Data were analyzed using the SPSS version 20.0 software. Results: One hundred and eight (30.9%) of participants had low baseline serum cortisol levels, while 57 (16.3%) had a low serum cortisol after short synacthen test. There was no significant relationship between the cortisol levels and clinical features of hypocortisolism, WHO clinical stage of HIV, hypernatremia or HAART regimen. There was a negative correlation between the stimulated serum cortisol and duration of diagnosis of HIV, participants BMI and CD4 counts. Conclusion: The biochemical evidence of hypocortisolism was common among patients infected with HIV, associated with a longer duration of HIV infection. However, none of CD4 counts, clinical features or HAART regimen were associated with hypocortisolism. DOI: https://dx.doi.org/10.4314/ahs.v19i2.18 Cite as: Akase IE, Habib AG, Bakari AG, Muhammad H, Gezawa ID. The prevalence and clinical profile of adrenocortical deficiency among HIV infected persons in Northern Nigeria. Afri Health Sci.2019;19(2): 1947-1952. https://dx.doi.org/10.4314/ahs.v19i2.1