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A novel pedagogic reflective strategy was developed to facilitate the teaching and learning of basic clinical biochemistry skills and to enhance critical thinking and reflection in clinical science students, specifically BSc Biomedical Science (BMS) and BMedSci Medical Science (BMedSci), at De Montfort University (UK) in 2016/17. Students that voluntarily resolved three clinical case studies proposed in 2016/17 and 2017/18 were shown to enhance their critical thinking and reflection [for each question, up to five marks are provided for their ability to: a) extract all the fundamental concepts, b) clarity of expression, c) reflect and comment]. A more detailed studied completed in 2018/19, contrarily has shown different trends in the learning/performance for each programme. Thus, BMS (n=19) students surprisingly displayed a significant reduction in their performance throughout the project (total marks were reduced from 10.68 to 5.0); meanwhile BMedSci (n=8) showed an increase in their performance, particularly related to their ability to synthesise information and clarity of expression (marks increased from 3.25 to 4.75). This discrepancy was not reflected in their impressions, as 83.4% of overall participants indicated an improvement in their learning performance, and 66.7% (33.3% undecided) reported acquisition of reflective skills. Although our results are inconclusive due to the low number of participants, students improved their communication and scientific writing skills.

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open access Human hair can be considered an appropriate matrix to assess chronic exposure to some natural radionuclides. Thus, hair has been suggested as a substitute for urine to determine chronic exposure to uranium as its presence is much higher in hair. However, there is little information about the exposure to relevant radionuclides in the Spanish population. We have determined the content of uranium-238 (U) and thorium-232 (Th) in scalp hair from 37 volunteers (20 to 24 years-old; 28 female and 9 male) from the Comunidad de Madrid (Spain). U and Th were monitored by ICP-MS after appropriate removal of exogenous contamination with Triton X-100. The limits of detection were: U (1.08 ng/g) and Th (0.47 ng/g). The hair concentrations were as follows (median and percentiles are provided in ng/g, for male and female participants, respectively): U [63.15 (31.29, 188.64) vs. 83.23 (22.13, 179.70)] and Th [2.35 (1.10, 7.11) vs. 1.49 (1.17, 3.35)]. Presence of these radionuclides did not show dependency due to sex, and were within reference ranges provided for a general Swedish population. Large variation was observed in the levels of both elements from one individual to another, which is in line with previous studies and could be due to a myriad of different exposures to U and Th in this population. However, the concentrations found in the Spanish participants’ hair were higher, although within the same order as those described in adults that live in areas with a high natural background of U and Th (Serbia and China). Our results, although preliminary, might indicate a moderate presence of U and Th in the environment in the Comunidad de Madrid that should be investigated in conjunction with identification of exposure pathways to assess risks to human health due to chronic exposure to these radionuclides.

open access Recently, large Human Bio-monitoring (HBM) projects have been carried out in different European countries as a tool to assess exposure to environmental pollutants. However, there are little data about the presence of metals in human hair in English populations, especially in children and young adults, even though such members of the population are more susceptible to environmental contaminants. 109 (20.5 ± 1.1 yrs-old; 32 male and 77 female) undergraduate students at De Montfort University (DMU, UK) were recruited between 2015-2016; student’s sex, age, weight, height and continental origin, was gathered. A Tanita® scale was used to determine (in %) body fat, water, muscle and bone mass. According to their body fat percentage, 28.4% were overweight and 7.3% underweight; female participants presented a higher prevalence of overweight. Scalp hair was collected, following previous methods, from 70 participants only (14 female, 56 male) from a diverse ethnic background (26 Asia, 24 Africa, 19 Europe, 1 America). Lead (Pb) content was determined in hair by ICP-MS after appropriate pre-treatment of each sample for eliminating exogenous contamination. Hair Pb concentration in female and male participants, respectively, were as follows (mean, median and percentiles are provided in µg/g): Pb [0.52, 0.28 (0.15, 0.75) vs. 0.48, 0.33 (0.19, 0.60)]. The content of Pb in hair did not show dependency on sex or ethnic background, which is in disagreement with a similar study performed by our group in Spanish university students (20-24 yrs-old), which showed significantly higher levels of Pb in female students. The absence of significance in DMU participants might be attributed to the differences in the number of hair samples collected by sex. A Pearson correlation study highlighted that Pb was not correlated with any of the anthropometric variables monitored. The presence of Pb in hair in the studied population could be attributed to dietary sources.

Future health professionals need to acquire analytic and diagnostic skills for prognosis and management of disease. However, the exponential advances in biomedical knowledge are making available new techniques and increasing the generation of data that require professionals equipped with the appropriate skills to interpret and process this new information. This is especially evident in biochemistry in which a myriad of new biomarkers can be currently monitored in a clinical tissue sample but, in turn, will require that the health professional is undertaking continuous learning to understand their meaning and interpretation. Reflection has been shown to be effective in facilitating continuous learning and gaining practical skills. Our innovative teaching group at De Montfort University (DMU, UK) implemented a novel pedagogic reflective strategy in the module “Clinical Biochemistry” shared in the BSc Biomedical Science (BMS) and BMedSci Medical Science (BMedSci) programmes in 2016/17, to encourage these final year students to think critically and use reflection to resolve three clinical biochemistry case studies of increasing difficulty distributed throughout the year. Students voluntarily resolved each case study and were provided with comprehensive feedback and marks for three main criteria, which students used to answer the case study: a) ability to extract all the fundamental concepts; b) ability to synthesise information and clarity of expression; and c) ability to reflect and comment. Preliminary results were not reliable due to poor engagement with this voluntary work, only 23 out of 142 students completed the first two case studies. For the 2017/18 iteration of the project, we performed small modifications and restricted the completion of the three case studies to the first term to encourage participation (as these final students are required to complete a demanding laboratory based final project in the second term). A total of 48 students (38 BMS and 10 BMedSci) voluntarily completed the first case study, although there was a notable reduction in the number of students that attempted the last case study. Marks gained for each of the criteria were compared statistically between them and between both academic years the project ran, to determine the effects of participation. Data analysed for both academic years indicated a significant increase in the marks received for ability to synthesise information and clarity of expression (p=0.01) and ability to reflect (p

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Metabolomics, understood as the science that manages the study of compounds from the metabolism, is an essential tool for deciphering metabolic changes in disease. The experiments rely on the use of high-throughput analytical techniques such as liquid chromatography coupled to mass spectrometry (LC-ToF MS). This hyphenation has brought positive aspects such as higher sensitivity, specificity and the extension of the metabolome coverage in a single run. The analysis of a high number of samples in a single batch is currently not always feasible due to technical and practical issues (i.e., a drop of the MS signal) which result in the MS stopping during the experiment obtaining more than a single sample batch. In this situation, careful data treatment is required to enable an accurate joint analysis of multi-batch data sets. This paper summarizes the analytical strategies in large-scale metabolomic experiments; special attention has been given to QC preparation troubleshooting and data treatment. Moreover, labeled internal standards analysis and their aim in data treatment, and data normalization procedures (intra- and inter-batch) are described. These concepts are exemplified using a cohort of 165 patients from a study in asthma.

Human scalp hair has been suggested as an appropriate tissue to determine body burden of various metals although this raises controversy in the scientific community due to different factors influencing their content in this matrix. Lithium (Li), selenium (Se) and cobalt (Co) have been linked to mood and brain function, recent reviews have reported an inverse association for these metals in human scalp hair with suicide rates. As a pilot study, we have determined the levels of these metals, including arsenic (As), mercury (Hg) and lead (Pb), in scalp hair from 37 young adults (20 to 24 years-old; 28 female and 9 male) from different towns in the Community of Madrid (Spain). After appropriate pre-treatment of samples following previous methodologies, metals were monitored by ICP-MS. The limits of detection were (in ng/g): Li (1.98), Se (5.14), Co (0.75), As (2.0), Hg (1.0), Pb (1.0). The concentrations were as follows (median and percentiles are provided in ng/g): Li 5.44 (4.45, 7.47), Se 309.04 (255.47, 331.79), Co 7.53 (2.78-17.04); and concentrations for As (0.014), Hg (1.72) and Pb (0.64) are presented as arithmetic means in µg/g. Although our results are not reliable due to the differences in the number of participants by sex, levels of Se and Hg were significantly higher in males, which is in accordance with similar studies and could be related to the higher and significant intake of fish and shellfish previously reported in male participants in this group of population by our team. In general, the presence of these metals in the Spanish group’s hair were within those highlighted in different studies performed in healthy Caucasian young adult populations. However, levels of Li, Co and Se were much lower than reference ranges reported for a Japanese population, which although from a different ethnic background, might suggest that the intake of these essential elements could be compromised in the Spanish group. Our results, although preliminary, might indicate that the intake of Li, Co and Se should be carefully monitored in Spanish young adults, as these have been recognised as essential metals for optimal brain function.

The rapid development and expansion of urban environments is occurring on a global scale resulting in new and unprecedented environmental hazards to human populations. Within these hazards, metal and metalloid topsoil contamination has become a worldwide health concern. Topsoil samples were randomly sampled in different urban parks (n=97), industrial (n=22) and garden (n=18) areas in Alcalá de Henares (Spain). Levels of Ag, Co, Fe, Mo, Pt, Rh, Sb, Se and Y were determined by ICP-MS following published methodologies. Se was not detected in any of the samples and Mo only in a few samples indicating little contamination by these metals. For other metals analysed, levels were within the same ranges or lower than those reported in other urban environments in similar studies, particularly for Pt and Rh, which could be described as emerging pollutants due to their use as catalysts to control fuel emissions. Thus, Pt and Rh were below the detection limits in 41.24% and 15.46% of the soil samples respectively, collected in the urban parks (“urban area”) across Alcalá de Henares, which may suggest an early stage of accumulation of these two metals. The “urban” area showed a generally lower presence of the monitored elements than topsoils collected from the garden and industrial areas. Significantly higher levels of Co (3.60 vs. 1.82 µg/g; p

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Introducción: Rhodnius pallescens es una especie silvestre que hace intrusión a las viviendas en zonas en las cuales se han presentado brotes de Chagas agudo en Colombia; y para el estudio de sus características biológicas y el monitoreo de la susceptibilidad o resistencia de poblaciones de campo a insecticidas, se requiere del uso de una gran cantidad de insectos mantenidos en el laboratorio. Objetivo: Establecer condiciones de cría de ninfas de R. pallescens que permitan su mejor aprovechamiento en ensayos biológicos. Metodología: Se utilizó una cepa de laboratorio de R. pallescens proveniente de San Martin (Cesar, Colombia) y se realizaron bioensayos para: estimar el tiempo de alimentación, establecer condiciones de cría, estimar tiempos de desarrollo ninfal y comparar la fecundidad usando dos fuentes de alimentación y varios tipos de soporte. Resultados: 60 minutos de ofrecimiento de alimento permite la alimentación de 95% de las ninfas. El promedio de oviposición diario/hembra fue de 2,7 huevos y no varío significativamente con el consumo de sangre de gallina o ratón. La duración promedio del ciclo de vida desde huevo hasta el estadio ninfa-V fue de 128,6 días. El uso de cartulina negra y plumas dentro de los frascos de cría mejora la oviposición. Ninfas-V alimentadas desde ninfa-I y pesadas a los 5 o 6 días permite un aprovechamiento del 89% de las ninfas. Conclusiones: Los resultados de este trabajo brindan conocimiento para la cría masiva y el uso de ninfas de Rhodnius pallescens en ensayos biológicos. Introduction: Rhodnius pallescens is a wild species which makes intrusion into dwellings in areas where there have been acute Chagas disease outbreaks in Colombia. Biologic research on their characteristics, and resistance to insecticides, requires the use of a large insect colony in the laboratory. Objective: To establish optimal breeding conditions of R. pallescens nymphs allowing better use in biological assays. Methodology: A laboratory strain of R. pallescens from San Martin (Cesar, Colombia) was used. Feeding time, breeding conditions, nymphal development times were assessed and fertility using two sources of feeding and different kinds of substrate was compared. Results: Providing food during 60 minutes allowed 95% of nymphs to be fed. The average daily oviposition per female was 2.7 eggs and did not vary significantly with the kind of blood used. The average duration of the life cycle from egg to nymph-V was 128.6 days. Using black cardboard and feathers in breeding jars increased oviposition. Nymphs-V (fed from nymph-I every 15 days) and weigthed at 5 or 6 days allowed the use of 89% of the nymphs. Conclusions: The results of this study allow offering recommendations for mass breeding and use of nymphs of R. pallescens in biological assays.

Introducción: Panstrongylus geniculatus es un triatomino silvestre, vector del Trypanosoma cruzi, intruso en domicilios humanos. Determinar la susceptibilidad a insecticidas de uso común en esta especie es indispensable para detectar prematuramente cepas resistentes. Objetivo: Este estudio se propuso analizar la susceptibilidad a lambdacihalotrina y fenitrotión en dos cepas (laboratorio y campo) de P. geniculatus. Metodología: se estableció la susceptibilidad a lambdacihalotrina y fenitrotión por aplicación tópica, en la cepa de laboratorio-Molagavita 2003 y en la población de campo-Chorreras 2012 en ninfas del primer estadio de P. geniculatus. Se calcularon valores de dosis letal 50 y dosis letal 99 (DL50 y la DL99) para cada insecticida. También se determinaron valores de grado de resistencia (GR) para cada insecticida: DL50 población de campo/DL50 cepa de laboratorio. Resultados: Las DL50 y DL99 en la población de campo y la cepa de laboratorio (en ng/i), fueron: 1,194; 5,764 y 0,024; 0,131 para lambdacihalotrina y 1,476; 7,354 y 0,482; 5,471 para fenitrotión, respectivamente. Los grados de resistencia fueron: GR= 48,9 para lambdacihalotrina y GR= 3,06 para fenitrotión. Conclusiones: La población de campo mostró resistencia a lambdacihalotrina y fenitrotión, probablemente como consecuencia del uso de agroquímicos en la zona. Implementar medidas para la detección temprana de resistencia en triatominos es importante en el diseño de programas de control vectorial. Introduction: Panstrongylus geniculatus, is a wild triatomine, vector of Trypanosoma cruzy, intruder in human homes. To determine the susceptibility to insecticides commonly used in this specie is essential to detect resistant strains prematurely. Objective: This study aimed to analyze the susceptibility to lambdacyhalothrin and fenitrothion in two strains (laboratory and field) of P. geniculatus. Methodology: susceptibility was established to lambdacyhalothrin and fenitrothion by topical application in the laboratory strain - Molagavita 2003 and field population - Chorreras 2012 in first instar nymphs of P. geniculatus. Values were calculated for lethal dosis 50 and lethal dosis 99 (LD50 and LD99) for each insecticide. Also values were determined to degree of resistance (GR) for each insecticide: field population LD50/LD50 laboratory strain. Results: The LD50 and LD99 in the field population and the laboratory strain (in ng/i) were: 1,194, 5,764 and 0,024, 0,131 for lambdacyhalothrin and 1,476, 7,354 and 0,482, 5,471 to fenitrothion, respectively. The degrees of resistance were: GR=48.9 for lambdacyhalothrin and GR=3.06 for fenitrothion. Conclusions: The field population showed resistance to lambdacyhalothrin and fenitrothion, probably as a result of the use of chemicals in the area. Implement measures for early detection of resistance in triatomines is important in the design of vector control programs.

A Carrier Ethernet Network (CEN) is a versatile, standardized, ubiquitous, carrier-class network. It possess several attributes that distinguish it from Metro Ethernet Networks (MENs), quality of service (QoS) being an integral one. Because CENs are designed to cover large areas (thousands of km) and transmit at high data rates (100 Gbps), these networks have a high bandwidth-delay product (BDP). Long distance transmissions that require data integrity suffer a transport-layer throughput bottleneck effect. Under these conditions, systems (including testbeds) exhibit a detrimental performance evaluation reduction as the round-trip time (RTT) increases. A new transport protocol is proposed to overcome the difficulties these networks incur, while providing QoS guarantees at the transport-layer level, hence maintaining the committed throughput levels established in the service level agreement (SLA). The proposed protocol, which is called Ethernet Services transport protocol (ESTP), is able to obtain congestion level feedback using only layer-4 information rather than assuming congestion based on a single packet loss event. An important aspect of this work is that it is validated by theoretical, simulated, and experimental results.

Carrier Ethernet is becoming the dominating backhaul network due to its flexibility, scalability, interoperability and low-cost. Carrier Ethernet networks (CENs) are inherently high bandwidth-delay product (BDP) networks, hence Traditional TCP, and similar variants, make undesirable choices of transport protocol mainly because of the aggressive multiplicative-decrease algorithm. The Ethernet-Services Transport Protocol (ESTP) has proven relieve the effects of the decrease algorithm by dynamically adjusting the transmission rate according to the level of congestion estimated in the network. It should be emphasized that most protocols detect congestion, but do not estimate the level of congestion. Also ESTP incorporates QoS information to further improve performance. In this work, a steady-state throughput analytical model of ESTP is derived, an experimental testbed is built and simulation results are obtained. All validation methods show good agreement.