Performance Evaluation of RAKE Receiver for UWB Systems using Measured Channels in Industrial Environments

The industrial environments are an important scenario for ultra wideband (UWB) communication systems. However, due to large number of metallic scatterers in the surroundings, the multipath offered by UWB channels is dense with significant energy. In this paper, the performance of RAKE receivers operating in a non line-of-sight (NLOS) scenario in these environments is evaluated. The channels used for the evaluation are measured in a medium-sized industrial environment. In addition, a standard IEEE 802.15.4a channel model is used for comparison with the results of the measured data. The performance of partial RAKE (PRake) and selective RAKE (SRake) is evaluated in terms of uncoded bit-error-rate (BER) using different number of fingers. The performance of maximal ratio combining (MRC) and equal gain combining (EGC) is compared for the RAKE receiver assuming perfect knowledge of the channel state. Finally, based on the simulation results, conclusions are drawn considering the performance and complexity issues for system design in these environments

Preliminary antidiarrhoeal activity of methanolic extracts of Securinega virosa (Euphorbiaceae)

Securinega virosa is used as remedy for diarrhoea in tropical Africa, but has not been investigated for its antidiarrhoeal activity. This study was therefore aimed at investigating the methanolic extracts of theleaves, stem bark and root bark for antidirrhoeal activity, using castor oil-induced diarrhoeal model in mice. The effects of these extracts on perfused isolated rabbit jejunum were also evaluated. Themethanolic leaves extract (8 x 10-5 – 1.6 x 10-3 mgml-1) produced a dose-dependent relaxation of the rabbit jejunum, while the methanolic stem bark and root bark extracts (2 x 10-5 – 3.2 x 10-3 mgml-1)produced contraction of the tissue. The methanolic root bark extract produced a dose-dependent protection against the castor oil- induced diarrhoea with the highest protection (100%), obtained at 100mgkg-1 comparable to that of loperamide (5 mgkg-1), the standard agent. The leaves extract also protected the mice but was not dose-dependent. The highest protection (60%) was obtained at thelowest dose (50 mgkg-1). The stem bark extract did not protect the animal against diarrhoea. The preliminary phytochemical analysis revealed that the three extracts contained similar phytochemicalconstituents which include alkaloids, tannins, saponins, flavonoids and cardiac glycosides. However, only the leaves extract contained anthraquinone glycosides. The acute toxicity test revealed the medianlethal dose (LD50) values for the leaves, stem bark and root bark extracts to be 1265, 288.5 and 774.6 mgkg-1 respectively. This suggests that the stem bark extract is relatively the most toxic. These results obtained revealed that the leaves and root bark extracts possess pharmacological activity against diarrhoea and may possibly explain the use of the plant in traditional medicine

Globrauneine A–F: six new triterpenoid esters from the leaves of Globimetula braunii

Phytochemical study was conducted on the leaves of Globimetula braunii which is a hemi parasitic plant belonging to the family Loranthaceae. Extraction was carried out using cold extraction method with increasing polarity of solvents i.e n-hexane, CH2Cl2 and MeOH. The components were separated by chromatographic technique and the structures of the compounds were elucidated by extensive spectroscopic analyses including MS, FTIR, 1D and 2D NMR, HRMS and chemical methods. Six new pentacyclic triterpenoid esters named as globrauneine A (1), globrauneine B (2), globrauneine C (3), globrauneine D (4), globrauneine E (5), and globrauneine F (6), together with six known compounds (7 – 12) were successfully isolated from the leaves of G. braunii growing on Piliostigma thonningii. These results depict a substantial support to the chemotaxonomy of the genus Globimetula

Human plasma biomarker responses to inhalational general anaesthesia without surgery

Background: Postoperative neurocognitive disorders may arise in part from adverse effects of general anaesthetics on the CNS, especially in older patients or individuals otherwise vulnerable to neurotoxicity because of systemic disease or the presence of pre-existing neuropathology. Previous studies have documented cytokine and injury biomarker responses to surgical procedures that included general anaesthesia, but it is not clear to what degree anaesthetics contribute to these responses. / Methods: We performed a prospective cohort study of 59 healthy volunteers aged 40–80 yr who did not undergo surgery. Plasma markers of neurological injury and inflammation were measured immediately before and 5 h after induction of general anaesthesia with 1 minimum alveolar concentration of sevoflurane. Biomarkers included interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), C-reactive protein (CRP), and neural injury (tau, neurofilament light [NF-L], and glial fibrillary acidic protein [GFAP]). / Results: Baseline biomarkers were in the normal range, although NF-L and GFAP were elevated as a function of age. At 5 h after induction of anaesthesia, plasma tau, NF-L, and GFAP were significantly decreased relative to baseline. Plasma IL-6 was significantly increased after anaesthesia, but by a biologically insignificant degree (<1 pg ml−1); plasma TNF-α and CRP were unchanged. / Conclusions: Sevoflurane general anaesthesia without surgery, even in older adults, did not provoke an inflammatory state or neuronal injury at a concentration that is detectable by an acute elevation of measured plasma biomarkers in the early hours after exposure. Clinical trial registration: NCT02275026

Evaluation of the Impacts of Taurine on Oxidative Stress Indices in Sera and Brain of Rats Exposed to Cypermethrin

Cypermethrin is a pyrethroid insecticide applied for pest control on animals and the environment. Taurine is a putative antioxidant and bioprotective amino acid. The purpose of the research was to evaluate the impacts of taurine on oxidative stress indices in the sera and brains of rats exposed to cypermethrin. Forty rats were assigned to five groups of eight rats each. Distilled water was given to the first group, while the second group received soya oil (2 ml/kg). Cypermethrin (20 mg/kg) was administered to the third group. The Taurine50+Cypermethrin group received taurine (50 mg/kg) and cypermethrin, while the Taurine100+Cypermethrin group was administered with taurine (100 mg/kg) and Cypermethrin. The treatments were given once daily by oral gavage for 35 days. Sera were obtained from the blood samples of the rats after the completion of the study for the determination of the oxidative stress indices (malondialdehyde concentration and the activities of antioxidant enzymes). Oxidative stress indices were analysed in the brains. Taurine significantly (P&lt; 0.05) augmented the superoxide dismutase activity in the sera. However, other oxidative stress indices were not ameliorated by taurine in the sera and the brains. Cypermethrin (20 mg/kg) did not overtly evoke oxidative stress in the sera and the brains of the rats in this study, probably because it is a moderately toxic insecticide. This is the first study that has investigated the effects of taurine on cypermethrin toxicity. Further research is warranted to expound the mechanisms of action of taurine and cypermethrin in biological systems

Pseudotumoral tracheobronchial amyloidosis mimicking asthma: a case report

<p>Abstract</p> <p>Introduction</p> <p>Tracheobronchial amyloidosis is an uncommon localized form of amyloidosis that can simulate a tracheal tumor. Clinical signs are not specific and the diagnosis is rarely given before performing a bronchoscopy with multiples biopsies.</p> <p>Case presentation</p> <p>We report the case of a 60-year-old Moroccan woman, complaining of dyspnea and wheezing for three years, who was treated at our institution for management of severe asthma. A bronchoscopy revealed a tumor formation of her trachea; multiples biopsies were performed and a diagnosis made of amyloid light-chain amyloidosis. She successfully received an endoscopic resection.</p> <p>Conclusion</p> <p>This case highlights the importance of routinely carrying out an endoscopy in any patient complaining of atypical bronchial symptoms or with uncontrolled asthma. Tracheal amyloidosis is a rare disease, confirmed by histological examination of bronchial biopsies, and the treatment of choice is based on the bronchoscopic resection.</p

Perception and beliefs about mental illness among adults in Karfi village, northern Nigeria

BACKGROUND: This study was designed to examine the knowledge, attitude and beliefs about causes, manifestations and treatment of mental illness among adults in a rural community in northern Nigeria. METHODS: A cross sectional study design was used. A pre-tested, semi-structured questionnaire was administered to 250 adults residing in Karfi village, northern Nigeria. RESULTS: The most common symptoms proffered by respondents as manifestations of mental illness included aggression/destructiveness (22.0%), loquaciousness (21.2%), eccentric behavior (16.1%) and wandering (13.3%). Drug misuse including alcohol, cannabis, and other street drugs was identified in 34.3% of the responses as a major cause of mental illness, followed by divine wrath/ God's will (19%), and magic/spirit possession (18.0%). About 46% of respondents preferred orthodox medical care for the mentally sick while 34% were more inclined to spiritual healing. Almost half of the respondents harbored negative feelings towards the mentally ill. Literate respondents were seven times more likely to exhibit positive feelings towards the mentally ill as compared to non-literate subjects (OR = 7.6, 95% confidence interval = 3.8–15.1). CONCLUSIONS: Our study demonstrates the need for community educational programs in Nigeria aimed at demystifying mental illness. A better understanding of mental disorders among the public would allay fear and mistrust about mentally ill persons in the community as well as lessen stigmatization towards such persons

Wavelet Cycle Spinning Denoising of NDE Ultrasonic Signals Using a Random Selection of Shifts

Wavelets are a powerful tool for signal and image denoising. Most of the denoising applications in different fields were based on the thresholding of the discrete wavelet transform (DWT) coefficients. Nevertheless, DWT transform is not a time or shift invariant transform and results depend on the selected shift. Improvements on the denoising performance can be obtained using the stationary wavelet transform (SWT) (also called shift-invariant or undecimated wavelet transform). Denoising using SWT has previously shown a robust and usually better performance than denoising using DWT but with a higher computational cost. In this paper, wavelet shrinkage schemes are applied for reducing noise in synthetic and experimental non-destructive evaluation ultrasonic A-scans, using DWT and a cycle-spinning implementation of SWT. A new denoising procedure, which we call random partial cycle spinning (RPCS), is presented. It is based on a cycle-spinning over a limited number of shifts that are selected in a random way. Wavelet denoising based on DWT, SWT and RPCS have been applied to the same sets of ultrasonic A-scans and their performances in terms of SNR are compared. In all cases three well known threshold selection rules (Universal, Minimax and Sure), with decomposition level dependent selection, have been used. It is shown that the new procedure provides a good robust denoising performance, without the DWT fluctuating performance, and close to SWT but with a much lower computational cost.This work was partially supported by Spanish MCI Project DPI2011-22438San Emeterio Prieto, JL.; Rodríguez-Hernández, MA. (2015). Wavelet Cycle Spinning Denoising of NDE Ultrasonic Signals Using a Random Selection of Shifts. 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Understanding client satisfaction with a health insurance scheme in Nigeria: factors and enrollees experiences

Abstract Background Health insurance schemes have been widely introduced during this last decade in many African countries, which have strived for improvements in health service provision and the promotion of health care utilization. Client satisfaction with health service provision during the implementation of health insurance schemes has often been neglected since numerous activities take place concurrently. The satisfaction of enrollees and its influencing factors have been providing evidence which have assisted in policy and decision making. Our objective is to determine the enrollee's satisfaction with health service provision under a health insurance scheme and the factors which influence the satisfaction. Methods This retrospective, cross-sectional survey took place between May and September 2008. Two hundred and eighty (280) enrollees insured for more than one year in Zaria-Nigeria were recruited using two stage sampling. Enrollee's satisfaction was categorized into more satisfied and less satisfied based on positive responses obtained. Satisfaction, general knowledge and awareness of contribution were each aggregated and assessed as composite measure. Logistic regression analysis was used to analyze factors that influenced the satisfaction of enrollees. Results A high satisfaction rate with the health insurance scheme was observed (42.1%). Marital status (p Conclusions This study highlighted the potential effects of general health insurance knowledge and awareness of contributions by end-users (beneficiaries) of such new program on client satisfaction which have significant importance. The findings provided evidence which have assisted the amendment and re-prioritization of the medium term strategic plan of operations for the scheme. Future planning efforts could consider the client satisfaction and the factors which influenced it regularly.</p