Variability and trends in rain height retrieved from GPM and implications on rain-induced attenuation over Nigeria.

To meet the rising demand for uninterrupted high-speed broadband internet services, the deployment of high-frequency bands for the transmission of radio signals is inevitable. Unfortunately, attenuation due to rain droplets remains the most challenging factor impeding effective radio wave propagation especially in earth-space satellite links operating at Ka and V bands. It is important to understand the attenuation and the parameters that determine its magnitude in order to provide an effective solution to this problem. Rain height as one of the attenuation input parameters was examined in detail. A study of its temporal evolution reveals that seasonal variation is insignificant while the spatial variation shows that it increases from the Sahel to the Coastal Zone of Nigeria. The work provides comprehensive rain height and rain-induced attenuation contour maps. These maps are expected to serve as a database for link budget calculations for different areas in Nigeria. Rain-induced attenuation maps for 1%, 0.1%, and 0.01% of time exceedance are provided at 20 GHz and 40 GHz for Ka and V band signals respectively.

Dynamical evolution of vertical profile of rain structures observed using ground-based radar over a tropical station.

In this study, measurements of vertical profiles of rain parameters have been made using vertically pointing micro rain radar (VPMRR) at Akure (7.30° N, 5.13° E). Rain parameter data collected over seven-month rainfall episodes during the intense rainy season (April to October) have been analyzed for a dynamical evolutionary trend over the site. Nearly all the episodes observed followed a similar pattern, hence, a single continuous rainfall episode occurring between 20:45:00 h and 21:14:00 h Greenwich Meridian Time (GMT) local time on 6th August 2018 is presented in this report. The results show no significant changes to the rain parameters (such as rain rate and liquid water content) nor contributed to the raindrop size distribution, based on average fall velocity of 6.55 m s-1 and rain rates within 1.3 and 2.6 mm h-1. This is to enable a stable fall for the dominant drops during the period. Further, the results revealed the transformation and collision of smaller drops to enhance a stable fall of larger drops during the rain event. The information from the study will be useful for radar meteorologists and microwave engineers in their designs.

Propagation curves and coverage areas of digital terrestrial television base stations in the tropical zone.

This study investigated the propagation curves and coverage areas of some Digital Terrestrial Television Broadcast Stations (DTTBS) over four climatic zones of coastal (Lagos), tropical rain forest (Akure), Sudan Savannah (Kaduna) and Sahel Savannah (Katsina) cities of Nigeria. Measurement of the Received Signal Strength (RSS) was carried out along different routes with each of the DTTBS as reference points. Measurements of RSS were carried out using two specified antenna receiver heights of 1.5 and 3.0 m for each data point. The GPS receiver was used to measure the geographic coordinates, elevation and Line of Sight (LOS) of data points along the routes in a drive test. Measurement was done during dry and wet season months at 1 km interval up to about 20 km in each of the selected routes covering a period of three years (2016-2018). Mean data were obtained and used to generate the propagation curves and the coverage areas over the study locations. Generally, results revealed that RSS undulates with LOS separation distance from DTTBS in all routes irrespective of seasons and routes. Particularly, RSS reduces to about half of its base station's value at about 8 and 12 km LOS from the DTTBS in Akure and Katsina respectively while, it reduces to about half of its base station's value at about 6 km from the DTTBS in Lagos and Kaduna. The implication of this is that higher coverage areas were obtained in suburban compared to urban cities. In addition, radial maps showing coverage areas and their grades useful for networking purposes were generated. Television White Spaces (TVWS) for secondary users were also proposed. For networking purposes and spatial arrangements of DTTBS that will ensure optimum coverage over the study locations, DTTBS can be sited at 8.0 and 13.5 km (LOS) interval from each other in urban and sub urban cities respectively. The overall results will enable system engineers to know the appropriate distance(s) and locations to site additional DTTBS for networking purposes and prepare power budget for optimum coverage area and good quality of services for terrestrial digital channels.

Comparative study on Radio Refractivity Gradient in the troposphere using Chaotic Quantifiers.

Complexity and nonlinear trend in the internal activities of the troposphere has been a great factor affecting the transmission and receiving of good quality of signals globally. In lieu of this, prediction of chaos and positive refractivity gradients for line-of-sight microwave radio paths is necessary for designing radio systems. Complexity in the troposphere due to changes in meteorological parameters can lead to the strong negative gradient (or super-refraction) which afterward lead to interference between terrestrial links and satellite earth stations. In this paper, a comparative study on the degree of complexity of Radio Refractivity Gradient (RRG) using Chaotic Quantifiers (CQ) such as Phase Plot Reconstruction (PPR), Average Mutual Information (AMI), False Nearest Neighbor (FNN), Lyapunov Exponent (LE), Tsallis Entropy (TS) and Recurrence Plot (RP) are discussed extensively. The RRG data (2011-2012) used in this work were obtained for 0 m to 100 m, from the archives of Tropospheric Data Acquisition Network (TRODAN) from five different stations namely; Akure (Geo. 7.299 ∘ N , 5.147 ∘ E ), Enugu (Geo. 6.46 ∘ N , 7.55 ∘ E ), Jos (Geo. 9.90 ∘ N , 8.86 ∘ E ), Minna (Geo. 9.58 ∘ N , 6.55 ∘ E ) and Sokoto (Geo. 13.01 ∘ N , 5.25 ∘ E ). The chaotic quantifiers are used to investigate the degree of complexity in the 30 minutes interval atmospheric data from the selected locations which is specified into rainy, dry and transition season months. The parallel and short diagonal lines observed depicts the evidence of chaos. However, the observed result shows that the RRG is higher during the rainy season than the dry season. In other words, the information is valid for the proposed data analysis, since the LE is actually directly proportional to the TE. Also, the results further show that the rainy season months exhibit higher chaoticity than the dry season months, which is equivalent to high radio refractivity gradient observed across the selected stations.

Total thyroidectomys in patient with McArdle's syndrome: Anesthetic management. / Tiroidectomía total en paciente con síndrome de McArdle: manejo anestésico.

McArdle disease or type V glycogenosis is a rare metabolic myopathy consisting of muscle loss and weakness. These patients have risks associated with anaesthesia. They can present with hypoglycaemia, rhabdomyolysis, acute renal failure, and electrolyte changes. It has also been associated with a higher incidence of malignant hyperthermia during the anaesthetic procedure. Intermittent compression due to the measurement of non-invasive pressure, postures on the operating table that may cause muscle contractures, or tremor caused by hypothermia or anaesthesia itself, may trigger rhabdomyolysis in these patients. In this article we present our experience in submitting a patient with McArdle's syndrome to general anaesthesia for total thyroidectomy due to multinodular euthyroid goitre.

Multidrug Resistance of Acinetobacter Baumannii in Ladoke Akintola University Teaching Hospital, Osogbo, Nigeria.

Acinetobacter baumannii is a ubiquitous pathogen that has emerged as a major cause of healthcare-associated infections at Ladoke Akintola University Teaching Hospital. Isolates were assayed according to standard protocol. The isolates were subjected to molecular techniques to detect blaOXA, blaTEM, blaCTX-M, and blaSHV genes in strains of the A. baumannii isolates. The prevalence of A. baumannii was 8.5% and was most prevalent among patients in the age group 51-60 (36%); the male patients (63.6%) were more infected than their female counterparts. Patients (72.7%) in the intensive care unit (ICU) were most infected with this organism. The isolates showed 100% resistance to both amikacin and ciprofloxacin and 90.9% to both ceftriaxone and ceftazidime, while resistance to the other antibiotics used in this study were: piperacillin (81.8%), imipenem (72.7%), gentamycin (72.2%), and meropenem (63.6%). None of the isolates was, however, resistant to colistin. PCR results showed that blaOXA, blaTEM, and blaCTX-M genes were positive in some isolates, while blaSHV was not detected in any of the isolates. This study has revealed that the strains of A. baumannii isolated are multiple drug resistant. Regular monitoring, judicious prescription, and early detection of resistance to these antibiotics are, therefore, necessary to check further dissemination of the organism.

In vivo Antimalarial Activities of Russelia Equisetiformis in Plasmodium Berghei Infected Mice.

The rising problem of resistance to most commonly used antimalarials remains a major challenge in the control of malaria suggesting the need for new antimalarial agents. This work explores the antiplasmodial potential of ethanol extract of Russelia equisetiformis in chloroquine Plasmodium berghei infected mice. Swiss albino mice were intraperitoneally infected with chloroquine-resistant P. berghei (ANKA). Experimental mice were treated for four days consecutively with graded doses of plant extracts and standard antimalarial drugs (artesunate and chloroquine) at a dose of 10 mg/kg body weight used as control. The extract showed a dose-dependent activity in the chemosuppression of P. berghei parasites by 31.6, 44.7, 48.4 and 86.5% at doses of 100, 200, 400 and 800 mg/kg, while chloroquine (10 mg/kg) and artesunate produced 59.4 and 68.4%, respectively. The extract showed a significant decrease in parasitaemia (P<0.05). The level of parasitemia and decrease in weight in all the treated groups was significantly lower (P<0.05) compared with the infected but untreated mice. The plant extract was devoid of toxicity at the highest dose tested (5000 mg/kg). The study concluded that the ethanol extract of R. equisetiformis possesses antimalarial effect, which supports the folk medicine claim of its use in the treatment of malaria.

¿Estamos los intensivistas dejando de creer en los beneficios de la nutrición? / Are intensivists losing faith in the benefits of nutrition?

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Development of time-trend model for analysing and predicting case pattern of dog bite injury induced rabies-like-illness in Liberia, 2014-2017.

OBJECTIVE: The post-civil war records of dog bite injuries (DBI) and rabies-like-illness (RLI) among humans in Liberia is a vital epidemiological resource for developing a predictive model to guide the allocation of resources towards human rabies control. Whereas DBI and RLI are high, they are largely under-reported. The objective of this study was to develop a time model of the case-pattern and apply it to derive predictors of time-trend point distribution of DBI-RLI cases. METHODS: A retrospective 6 years data of DBI distribution among humans countrywide were converted to quarterly series using a transformation technique of Minimizing Squared First Difference statistic. The generated dataset was used to train a time-trend model of the DBI-RLI syndrome in Liberia. An additive detenninistic time-trend model was selected due to its performance compared to multiplication model of trend and seasonal movement. Parameter predictors were run on least square method to predict DBI cases for a prospective 4 years period, covering 2014-2017. RESULTS: The two-stage predictive model of DBI case-pattern between 2014 and 2017 was characterised by a uniform upward trend within Liberia's coastal and hinterland Counties over the forecast period. CONCLUSION: This paper describes a translational application of the time-trend distribution pattern of DBI epidemics, 2008-2013 reported in Liberia, on which a predictive model was developed. A computationally feasible two-stage time-trend permutation approach is proposed to estimate the time-trend parameters and conduct predictive inference on DBI-RLI in Liberia.

Utilidad de la resonancia magnética potenciada en difusión en pacientes con lesiones focales por traumatismo craneoencefálico grave / Utility of diffusion-weighted magnetic resonance imaging in severe focal traumatic brain injuries

Objetivo Describir el coeficiente de difusión aparente (CDA) medido mediante resonancia magnética potenciada en difusión (RMD) en una serie de pacientes con traumatismo craneoencefálico (TCE) grave, sus aspectos clínicos y pronósticos y sus posibles implicaciones Diseño Estudio observacional, descriptivo de serie de casos Pacientes e intervenciones Pacientes con TCE grave, ingresados en UCI que no presentan contraindicaciones para traslado y realización de resonancia magnética (RM). Se realizó RM usando un scanner de 1.5 Tesla. Las imágenes potenciadas en difusión se obtuvieron usando una secuencia de pulso eco-planar con las siguientes características: TR 10.000 ms, TE 126,9 ms, valores b 1.000 s/mm2 en las tres direcciones del espacio. Combinando los tres sets de imágenes se obtuvo una imagen isotrópica que constituyó el mapa de los CDA medios. Resultados RMD se realizó en 23 pacientes con TCE grave ingresados en UCI entre 2001 y 2004. Se seleccionaron para su análisis 26 regiones de interés y se recogió el CDA en cada una de ellas. Se observó un incremento en la difusión en las lesiones ocupantes de espacio no evacuadas respecto a otros tipos de lesión y a valores normales. El pronóstico, según la escala de resultados de Glasgow, fue peor en los pacientes con valores de CDA más bajos. Conclusiones Los CDA medios fueron mayores que los valores normales y mayores en las contusiones que en otros tipos de lesión, como expresión de edema extracelular. Los CDA estaban disminuidos en pacientes con mal pronóstico sugiriendo una asociación entre isquemia y pronóstico(AU)

Objective To describe the apparent diffusion coefficient (ADC) in a series of severe traumatic brain injuries, their clinical and outcome features, and possible implications. Design A descriptive, observational case-series study was carried out. Patients and interventions Patients with severe traumatic brain injuries (TBIs) admitted to the ICU were subjected to MRI study using a 1.5 T scanner. Diffusion-weighted images (DWMR) were obtained using the following echo-planar pulse sequence: TR 10000 ms, TE 126.9 ms, with b values 1000 s/mm2 in the three spatial dimensions. Combining the three sets of images, an isotropic image conforming a map of the mean ADCs was obtained. Results DWMR was performed in 23 patients with severe TBI admitted to the ICU between 2001 and 2004. In the MR images we selected 26 regions of interest (ROIs) where ADC was recorded. We observed a clear increase in diffusion in non-treated space-occupying lesions versus other types of injuries and the normal values. A poorer outcome was recorded in patients with lower ADC values. Conclusions Mean ADC in the lesions was greater than the normal values and greater in contusions than in other types of injuries, as an expression of extracellular edema. ADCs were decreased in patients with a poor outcome, suggesting an association between ischemia and the patient prognosis (AU)

Bloqueo axilar ecoguiado frente a bloqueo infraclavicular ecoguiado para la cirugía de miembro superior / Ultrasound-guided axillary block versus ultrasound-guided infraclavicular block for upper extremity surgery

Introducción. Con la incorporación de la ecografía en la práctica habitual de la anestesia regional, el bloqueo infraclavicular ha ido ganando popularidad. La mayoría de los abordajes de anestesia regional del miembro superior tienen una alta tasa de éxito, y las diferencias en la eficacia y en la calidad del bloqueo deberían favorecer la elección de una técnica frente a otra. Nuestro objetivo fue evaluar si el bloqueo infraclavicular del plexo braquial presentaba ventajas respecto al axilar en relación con los tiempos de instauración y efectividad clínica. Métodos. Estudio comparativo, prospectivo, aleatorizado entre el bloqueo infraclavicular ecoguiado y el bloqueo axilar ecoguiado en la cirugía de miembro superior. Se evaluó el tiempo anestésico total (definido como la suma del tiempo de realización del bloqueo y el tiempo de instauración). Se registró la tasa de éxito (anestesia quirúrgica), la duración de la analgesia, el dolor postoperatorio mediante escala visual analógica y la incidencia de complicaciones durante y tras la técnica (hasta 24 h después). Resultados. Se incluyeron 82 pacientes, que se dividieron en 2 grupos: bloqueo infraclavicular (BI) (n = 42) y bloqueo axilar (BA) (n = 40). No se observaron diferencias entre los 2 grupos en cuanto a tiempo de realización del bloqueo, tasa de éxito (90-95%) y dolor postoperatorio. Comparado con el abordaje infraclavicular, el grupo BA requirió un mayor tiempo de instauración, 10,2 min (DE ± 1,4) frente a 6,35 min (DE ± 2), siendo esta diferencia estadísticamente significativa (p < 0,05). Además, hubo una mayor duración de la analgesia en el grupo BI que en el grupo BA, 20 h (DE ± 1,36) frente a 13,70 h (DE ± 2,16), respectivamente. Las únicas complicaciones registradas fueron punciones vasculares, que no tuvieron incidencias. Conclusiones. El BI proporciona una eficacia similar, con un menor tiempo de instauración del bloqueo y una analgesia más duradera que el BA(AU)

Background. Most upper limb regional anaesthesia techniques are successful, and differences in efficacy should dictate the choice of technique. Methods. This prospective, randomised study compares ultrasound-guided infraclavicular (IB) and ultrasound-guided axillary brachial plexus blocks (AB) for upper limb surgery. Anaesthesia time (performance time and onset time) was the primary outcome measure. The success rate (surgical anaesthesia), analgesia duration, postoperative pain scores, and the incidence of complications over the following 24 h were recorded. Results. A total of 82 patients were included in the study, and received either IB (n = 42) or AB (n = 40). No differences were observed between the 2 groups in terms of total anaesthesia-related time, performance time, success rate (90-95%), or postoperative pain scores. Compared with the infraclavicular approach, ultrasound-guided AB group required a longer onset time, 10.2 min (SD ± 1.4), than IB group, 6.35 min (SD ± 2). IB was also associated with a longer analgesia duration than that of AB; 20 h (SD ± 1.36) versus 13.70 h (SD ± 2.16), respectively. The only complications we observed were uneventful vascular punctures. Conclusions. We can conclude that compared to ultrasound-guided AB, ultrasound-guided IB provides a similar efficacy, a shorter onset time and longer lasting analgesia(AU)

[Ultrasound-guided axillary block versus ultrasound-guided infraclavicular block for upper extremity surgery]. / Bloqueo axilar ecoguiado frente a bloqueo infraclavicular ecoguiado para la cirugía de miembro superior.

BACKGROUND: Most upper limb regional anaesthesia techniques are successful, and differences in efficacy should dictate the choice of technique. METHODS: This prospective, randomised study compares ultrasound-guided infraclavicular (IB) and ultrasound-guided axillary brachial plexus blocks (AB) for upper limb surgery. Anaesthesia time (performance time and onset time) was the primary outcome measure. The success rate (surgical anaesthesia), analgesia duration, postoperative pain scores, and the incidence of complications over the following 24h were recorded. RESULTS: A total of 82 patients were included in the study, and received either IB (n=42) or AB (n=40). No differences were observed between the 2 groups in terms of total anaesthesia-related time, performance time, success rate (90-95%), or postoperative pain scores. Compared with the infraclavicular approach, ultrasound-guided AB group required a longer onset time, 10.2min (SD±1.4), than IB group, 6.35min (SD±2). IB was also associated with a longer analgesia duration than that of AB; 20h (SD±1.36) versus 13.70h (SD±2.16), respectively. The only complications we observed were uneventful vascular punctures. CONCLUSIONS: We can conclude that compared to ultrasound-guided AB, ultrasound-guided IB provides a similar efficacy, a shorter onset time and longer lasting analgesia.

[Utility of diffusion-weighted magnetic resonance imaging in severe focal traumatic brain injuries]. / Utilidad de la resonancia magnética potenciada en difusión en pacientes con lesiones focales por traumatismo craneoencefálico grave.

OBJECTIVE: To describe the apparent diffusion coefficient (ADC) in a series of severe traumatic brain injuries, their clinical and outcome features, and possible implications. DESIGN: A descriptive, observational case-series study was carried out. PATIENTS AND INTERVENTIONS: Patients with severe traumatic brain injuries (TBIs) admitted to the ICU were subjected to MRI study using a 1.5 T scanner. Diffusion-weighted images (DWMR) were obtained using the following echo-planar pulse sequence: TR 10000 ms, TE 126.9 ms, with b values 1000 s/mm2 in the three spatial dimensions. Combining the three sets of images, an isotropic image conforming a map of the mean ADCs was obtained. RESULTS: DWMR was performed in 23 patients with severe TBI admitted to the ICU between 2001 and 2004. In the MR images we selected 26 regions of interest (ROIs) where ADC was recorded. We observed a clear increase in diffusion in non-treated space-occupying lesions versus other types of injuries and the normal values. A poorer outcome was recorded in patients with lower ADC values. CONCLUSIONS: Mean ADC in the lesions was greater than the normal values and greater in contusions than in other types of injuries, as an expression of extracellular edema. ADCs were decreased in patients with a poor outcome, suggesting an association between ischemia and the patient prognosis.

Congenital lobar emphysema in a Nigerian neonate: a rare cause of neonatal respiratory distress.

Congenital lobar emphysema (CLE) is a notable cause of respiratory distress in neonates, however it remains a diagnostic challenge due to inadequate facilities and low level of experience. The management of this condition also is a bigger challenge due to paucity of expertise and relatively non-existent well-equiped neonatal intensive care unit in this part of the world. Here we present the case of a 5- day old baby who presented at Lagoon Hospital, Apapa with history of severe respiratory distress since birth. CT scan of the chest confirmed an emphysematous left upper lobe with contralateral mediastinal shift. The baby had a left posterolateral thoracotomy with left upper lobectomy and thereafter was electively ventillated for forty eight hours in the neonatal intensive unit. He had an uneventful postoperative course and was discharged from the hospital within one week forfollow-up in the clinic.

Hipotensión grave y prolongada tras sobredosis de candesartán y amlodipino por intento autolítico: primer caso comunicado en la literatura / Severe and prolonged hypotension after overdose of candesartan and amlodipine from attempted suicide: first case

La asociación de varios hipotensores para el tratamiento de la hipertensión arterial suele ser una práctica frecuente y útil, aunque en ocasiones puede dificultar el manejo de una sobredosificación o de posibles efectos adversos. Se presenta el caso de un paciente joven que requirió cuidados intensivos por hipotensión grave y prolongada con hipoperfusión y acidosis metabólica, tras la ingesta estimada de 1280 mg de candesartán y 500 mg de amlodipino por intento autolítico, suponiendo la primera citación en la literatura de una sobredosis por esta combinación terapéutica. Se describe la situación clínica y analítica del enfermo durante las primeras 25 horas de su evolución y el tratamiento al que fue sometido, haciendo especial énfasis en la fisiopatología provocada por las características farmacológicas de ambos medicamentos (AU)

The combination of several antihypertensives drugs for the treatment of hypertension is common and useful, though sometimes difficult to deal with a possible overdose or adverse effects. We report the case of a young patient who required intensive care for severe and prolonged hypotension with hypoperfusion and metabolic acidosis after the estimated ingestion of 1280 mg of candesartan and 500 mg of amlodipine for attempted suicide, assuming the first citation in the literature of an overdose by this therapy. We describe the clinical and laboratory status of the patient during the first 25 hours of evolution and the treatment applied, with special emphasis on the pathophysiology caused by the pharmacological characteristics of both drugs (AU)