44 research outputs found
3D Printing Filaments Facilitate the Development of Evanescent Wave Plastic Optical Fiber (POF) Chemosensors
One of the major difficulties in the development of evanescent wave optical fiber sensors (EWOFS) lies in the complexity of the manufacturing of the chemosensitive element, particularly when using plastic optical fibers (POFs). While these fibers are appealing waveguides thanks to their low cost, ease of connectorization and robustness, the need for removing the cladding material complicates the EWOFS fabrication. In this paper we discuss how 3D printing filaments can serve as an alternative to commercially available POF for the development of EWOFS. In the process of replacing the traditional POF, we compared the performance of two EWOFS for monitoring airborne formaldehyde. These sensitive elements were manufactured either from 1.75 mm diameter 3D printing filaments, or from a commercially available POF. After the optimization of their respective fabrication protocols, the analytical performance of the two formaldehyde EWOFS was compared in terms of sensitivity and reproducibility. In this regard, the easy-to-manufacture 3D printing filament-based waveguides provided 5-fold lower detection limits with respect to the commercial POF-based sensors. Although no statistically significant differences were found in terms of reproducibility, the simplification of the sensor manufacturing process together with the increased analytical performance for chemical sensing spur the use of 3D printing filaments for the development of new POF-based EWOFS.Depto. de Química OrgánicaFac. de Ciencias QuímicasTRUEEU-LIFE Programpu
Knowledge gaps on paediatric respiratory infections in Morocco, Northern Africa
BACKGROUND: The burden of acute respiratory infections (ARI)
among Moroccan children remains significant. However, scarce
information is available regarding trends in its epidemiology
and etiology, or regarding its associated prognostic factors.
The purpose of this work was to review available data on the
burden of ARI among children under five years of age in Morocco.
METHODS: A systematic review was conducted for the period
1997-2014 using the PRISMA proposed methodology. Various online
databases were screened, in addition to physical libraries of
Moroccan medical schools, and official reports of the Moroccan
Ministry of Health. Search queries in English and French
languages included: Respiratory Tract Infections, pneumonia,
epidemiology, etiology, microbiology, mortality and Morocco. The
documents were included for analysis when they reported original
data on the incidence, distribution, or a clinical description
of the diseases or their etiology or described clinical
management or national preventive strategies. RESULTS:
Thirty-two documents were included in the final analysis. 21 of
which had been published. In 2012, ARI caused 13% of paediatric
deaths, half of the consultations at health facilities and third
of the paediatric admissions. The microorganisms more frequently
identified among hospitalized children were Streptococcus
pneumoniae (38%) and Haemophilus influenza type b (Hib) (15%).
The MOH introduced Hib vaccines into the national immunization
program (PNI) in 2007and the 13-valent vaccine against
pneumococcus in 2010. The national first line antibiotics
recommended for non-severe ambulatory treatment is Amoxicillin.
Studies of antibiotic resistance showed from 1998 to 2008 a 22%
increase in the rate of penicillin non-susceptibility among
Streptococcus pneumoniae isolates. Viral respiratory infections
and the role attributed to air pollution in the incidence of ARI
have been poorly characterized. CONCLUSIONS: Further efforts
should be made towards the development of adequate surveillance
programs to better clarify the epidemiology, etiology,
antimicrobial susceptibility patterns and the effectiveness of
the preventives and curatives strategies in place against
paediatric ARIs in Morocco. Additionally, a holistical approach
should be used to identify the heath determinants of ARIs among
children
Diseño de un workload real para un benchmark de bases de datos orientadas a grafos
82 p.Junto al surgimiento de aplicaciones que requieren almacenar y analizar grandes
cantidades de información no estructurada y compleja, surgen tambien los sistemas
de gestión de bases de datos orientadas a grafos (SGBDG). Estos sistemas se caracterizan porque su enfoque no está en gestionar datos de forma individual y aislada,sino que ponen énfasis en las relaciones existentes entre dichos datos.
El surgimiento de los SGBDG trae consigo la necesidad de realizar benchmarking
sobre ellos a modo de poder establecer comparaciones. En este contexto, GDBench
es un benchmark enfocado a evaluar el rendimiento de sistemas de bases de datos
considerando como caso de uso una red social. Sin embargo, la carga de trabajo
(workload) de GDBench no representa un escenario real. En efecto, el workload utilizado por GDBench era aleatorio, no considerando una lógica desde el punto de vista del orden en el que eran ejecutadas las operaciones. En esta memoria se presenta el desarrollo de un workload real, basado en el análisis de una red social existente (Facebook), para GDBench. El nuevo workload simula el comportamiento de un conjunto de usuarios interactuando en la red social definida por el esquema de datos de GDBench, combinando un conjunto de 6 consultas
interactivas y 6 consultas analíticas.
El benchmark resultante fue evaluado sobre cuatro sistemas de bases de datos,
considerando aquellas orientadas a grafos (Sparksee y Neo4j), RDF (Apache Jena) y
relacional (PostgreSQL). Sobre cada uno de los sistemas de bases de datos se ejecut o
el workload aleatorio y el workload real. Al realizar la comparación de resultados,
se obtuvo que si bien se produjeron diferencias en los tiempos de ejecución de las consultas que conformaban el workload, éstas no fueron lo su cientemente signi cativas como para alterar los resultados del proceso de benchmarking. Como trabajo futuro se plantea un uso más intensivo del benchmark para evaluar la influencia del workload en el proceso de benchmarking. Palabras claves: SGBDG, BDOG, Benchmarking, Work ow, Workload./ABSTRACT: Along with the emergence of applications that require storing and analyzing large amounts of unstructured and complex information, graph database management systems (GDBMS) also emerge. These systems are characterized because their approach is not to manage data in an individual and isolated way, but rather they emphasize the relations existing between the data. The emergence of GDBMS brings with it the need to perform benchmarking on these systems so that comparisons can be made. In this context, GDBench is a benchmark oriented to evaluate the performance of database systems considering social network as a use case. However, GDBench's workload does not represent a real scenario. In fact, the workload used by GDBench was random, not considering a logic from the point of view of the order in which the operations were executed. In this document we present the development of a real workload, based on the analysis of an existing social network (Facebook). The new workload simulates the behavior of a set of users interacting in the social network de ned by the GDBench data schema, combining a set of 6 interactive queries and 6 analytic queries. The resulting benchmark was evaluated on four database systems, considering those oriented to graphs (Sparksee and Neo4j), RDF (Apache Jena) and relational (PostgreSQL). Over each database system was executed either the random workload and the real workload. When we compared the results we found that there were differences in the execution times of the queries, but the di erences were not signi cant enough to alter the results of the benchmarking process. As future work, we propose a more intensive use of the benchmark to evaluate the influence of workload in the benchmarking process
Luminescent molecularly imprinted polymer nanocomposites for emission intensity and lifetime rapid sensing of tenuazonic acid mycotoxin
Tenuazonic acid ((5S)-3-acetyl-5-[(2S)-butan-2-yl]-4-hydroxy-2,5-dihydro-1H-pyrrol-2-one, TeA) is a widespread Alternaria fungi mycotoxin in food produce. This toxin may be allergenic and provoke hay fever and asthma. Therefore, rapid methods to selectively detect TeA are needed. With this aim, we have engineered a novel trifunctional (red-luminescent, polymerizable, TeA-sensitive) ruthenium(II)-bipyridyl complex with 2,2′-biimidazole. Its peripheral N–H moieties recognize the enolate form of 1,3-dicarbonyl compounds (including TeA) in partially aqueous media. Such a binding decreases the luminescence intensity and lifetime (0.2 μs) of the Ru(II) probe. The probe also bears acrylate groups that allow radical copolymerization with methacrylamide and ethylene glycol dimethacrylate in the presence of TeA, to yield 9-nm thick luminescent molecularly imprinted polymer (MIP) shells onto 200-nm silica cores. The SiO2@Ru-MIP nanocomposite displays a very fast response (<5 s) suitable for real-time detection of TeA. No cross-sensitivity to other common food mycotoxins that also contain a β-hydroxycarbonyl moiety (alternariol, β-zeranol, cyclopiazonic acid) is observed. Detection limits of 63.8 μg L⁻1 and 75.2 μg L⁻1 under steady-state and time-resolved luminescence detection, respectively, have been measured without further optimization. The use of emission lifetime variations to monitor the levels of a target analyte has never been reported for a luminescent MIP-based sensor
Detection of Streptococcus pneumoniae and Haemophilus influenzae type B by real-time PCR from dried blood spot samples among children with pneumonia: a useful approach for developing countries
Correction https://doi.org/10.1371/journal.pone.0147678Background: Dried blood spot (DBS) is a reliable blood collection method for storing samples at room temperature and easily transporting them. We have previously validated a Real-Time PCR for detection of Streptococcus pneumoniae in DBS. The objective of this study was to apply this methodology for the diagnosis of S. pneumoniae and Haemophilus influenzae b (Hib) in DBS samples of children with pneumonia admitted to two hospitals in Mozambique and Morocco. Methods: Ply and wzg genes of S. pneumoniae and bexA gene of Hib, were used as targets of Real-Time PCR. 329 DBS samples of children hospitalized with clinical diagnosis of pneumonia were tested. Results: Real-Time PCR in DBS allowed for a significant increase in microbiological diagnosis of S. pneumoniae and Hib. When performing blood bacterial culture, only ten isolates of S. pneumoniae and none of Hib were detected (3·0% positivity rate, IC95% 1·4-5·5%). Real-Time PCR from DBS samples increased the detection yield by 4x fold, as 30 S. pneumoniae and 11 Hib cases were detected (12·4% positivity rate, IC95% 9·0-16·5%; P<0·001). Conclusion: Real-Time PCR applied in DBS may be a valuable tool for improving diagnosis and surveillance of pneumonia caused by S. pneumoniae or Hib in developing countries
Etiology, epidemiology and clinical characteristics of acute moderate-to-severe diarrhea in children under 5 years of age hospitalized in a referral pediatric hospital in Rabat, Morocco
The objective of the study was to describe the etiology, epidemiology, and clinical characteristics of the principal causes of acute infectious diarrhea requiring hospitalization among children under 5 years of age in Rabat, Morocco. A prospective study was conducted from March 2011 to March 2012, designed to describe the main pathogens causing diarrhea in hospitalized children >2 months and less than 5 years of age. Among the 122 children included in the study, Enteroaggregative E. coli (EAEC) and rotavirus were the main etiologic causes of diarrhea detected. Twelve (9.8%) children were referred to the intensive care unit, while 2, presenting infection by EAEC and EAEC plus a Shigella sonnei respectively, developed a hemolytic uremic syndrome. Additionally, 6 (4.9%) deaths occurred with EAEC being isolated in four of these cases. Diarrheogenic E. coli and rotavirus play a significant role as the two main causes of severe diarrhea while other pathogens such as norovirus or parasites seem to have a minimal contribution. Surveillance and prevention programs to facilitate early recognition and improved management of potentially life-threatening diarrhea-episodes are needed
Characterization of Vaginal Escherichia coli Isolated from Pregnant Women in Two Different African Sites
The relevance of vaginal colonization of pregnant women by
Escherichia coli is poorly understood, despite these strains
sharing a similar virulence profile with other extraintestinal
pathogenic E. coli producing severe obstetric and neonatal
infections. We characterized the epidemiology, antimicrobial
susceptibility and virulence profiles of 84 vaginal E. coli
isolates from pregnant women from Rabat (Morocco) and Manhica
(Mozambique), two very distinct epidemiological settings. Low
levels of antimicrobial resistance were observed to all drugs
tested, except for trimethoprim-sulfamethoxazole in Manhica,
where this drug is extensively used as prophylaxis for
opportunistic HIV infections. The most prevalent virulence
factors were related to iron acquisition systems. Phylogroup A
was the most common in Rabat, while phylogroups E and
non-typeable were the most frequent in Manhica. Regardless of
the apparently "low virulence" of these isolates, the frequency
of infections is higher and the outcomes more devastating in
constrained-resources conditions, especially among pregnant
women and newborns
Prevalence, antimicrobial resistance and serotype distribution of group B streptococcus isolated among pregnant women and newborns in Rabat, Morocco
PURPOSE: Group B streptococcus (GBS) is an important cause of
neonatal sepsis worldwide. Data on the prevalence of maternal
GBS colonization, risk factors for carriage, antibiotic
susceptibility and circulating serotypes are necessary to tailor
adequate locally relevant public health policies. METHODOLOGY: A
prospective study including pregnant women and their newborns
was conducted between March and July 2013 in Morocco. We
collected clinical data and vagino-rectal and urine samples from
the recruited pregnant women, together with the clinical
characteristics of, and body surface samples from, their
newborns. Additionally, the first three newborns admitted every
day with suspected invasive infection were recruited for a
thorough screening for neonatal sepsis. Serotypes were
characterized by molecular testing. RESULTS: A total of 350
pregnant women and 139 of their newborns were recruited. The
prevalence of pregnant women colonized by GBS was 24 %. In 5/160
additional sick newborns recruited with suspected sepsis, the
blood cultures were positive for GBS. Gestational hypertension
and vaginal pruritus were significantly associated with a
vagino-rectal GBS colonization in univariate analyses. All of
the strains were susceptible to penicillin, while 7 % were
resistant to clindamycin and 12 % were resistant to
erythromycin. The most common GBS serotypes detected included V,
II and III. CONCLUSION: In Morocco, maternal GBS colonization is
high. Penicillin can continue to be the cornerstone of
intrapartum antibiotic prophylaxis. A pentavalent GBS vaccine
(Ia, Ib, II, III and V) would have been effective against the
majority of the colonizing cases in this setting, but a
trivalent one (Ia, Ib and III) would only prevent 28 % of the
cases
Quality of care and maternal mortality in a tertiary-level hospital in Mozambique: a retrospective study of clinicopathological discrepancies
Background: Although an increasing number of pregnant women in resource-limited areas deliver in health-care facilities, maternal mortality remains high in these settings. Inadequate diagnosis and management of common life-threatening conditions is an important determinant of maternal mortality. We analysed the clinicopathological discrepancies in a series of maternal deaths from Mozambique and assessed changes over 10 years in the diagnostic process. We aimed to provide data on clinical diagnostic accuracy to be used for improving quality of care and reducing maternal mortality. Methods: We did a retrospective analysis of clinicopathological discrepancies in 91 maternal deaths occurring from Nov 1, 2013, to March 31, 2015 (17 month-long period), at a tertiary-level hospital in Mozambique, using complete diagnostic autopsies as the gold standard to ascertain cause of death. We estimated the performance of the clinical diagnosis and classified clinicopathological discrepancies as major and minor errors. We compared the findings of this analysis with those of a similar study done in the same setting 10 years earlier. Findings: We identified a clinicopathological discrepancy in 35 (38%) of 91 women. All diagnostic errors observed were classified as major discrepancies. The sensitivity of the clinical diagnosis for puerperal infections was 17% and the positive predictive value was 50%. The sensitivity for non-obstetric infections was 48%. The sensitivity for eclampsia was 100% but the positive predictive value was 33%. Over the 10-year period, the performance of clinical diagnosis did not improve, and worsened for some diagnoses, such as puerperal infection. Interpretation: Decreasing maternal mortality requires improvement of the pre-mortem diagnostic process and avoidance of clinical errors by refining clinical skills and increasing the availability and quality of diagnostic tests. Comparison of post-mortem information with clinical diagnosis will help monitor the reduction of clinical errors and thus improve the quality of care