10 research outputs found
Fibre Distribution and the Process-Property Dilemma
The options for the fibre reinforcement of polymer matrix composites cover a range from short-fibre chopped strand mat, through woven fabric to unidirectional pre-impregnated (prepreg) reinforcements. The modelling of such materials may be simplified by assumptions such as perfect regular packing of fibres and the total absence of fibre waviness. However, these and other features such as the crimp or waviness in woven fabrics make real materials more complex than the simplified models. Clustering of fibres creates fibre-rich and resin-rich volumes (FRV and RRV respectively) in the composites. Prior to impregnation, large RRV will be pore-space that can expedite the flow of resin in liquid composite moulding processes (especially resin transfer moulding (RTM) and resin infusion under flexible tooling (RIFT). In the composite, the clustering of fibres tends to reduce the mechanical properties. The use of image processing and analysis can permit micro-/meso-structural characterisation which may correlate to the respective properties. This chapter considers the quantification of microstructure images in the context of the process-property dilemma for woven carbon-fibre reinforced composites with the aim of increasing understanding of the balance between processability and mechanical performance
Analiza pozyskania i możliwość wykorzystania na cele energetyczne szyszek gatunków drzew iglastych z polskich wyłuszczarni w latach 2009-2012
The paper presents
data on acquisition of conifer cones from
16 seed extraction plants operating on the territory
of Poland during four consecutive years from
2009 to 2012. A high variability was observed in
provision of seed units to the seed exaction plants
related to specificity of a given seed year. During
the four analyzed years the most commonly
acquired cone was that of Scots pine – above 1.3
thousand Mg, and the most rare were pines of
common fir – 31 Mg. The plants that process the
largest number of cones are seed extraction plants
in forest districts of Jarocin, Kluczbork and Rytel
where over 600 Mg of cones were extracted. Conifer
cones, which are usually treated as waste,
may be utilized as an energy source. After seed
extraction their mass decreases from 16 to 30%
depending on the species. The analysis showed
that the annual quantity of conifer cones that can
be used as an energy source is on average 270 Mg
of empty cones.W artykule przedstawiono dane liczbowe dotyczące pozyskania szyszek czterech gatunków drzew: sosny zwyczajnej, świerka pospolitego, modrzewia europejskiego i jodły zwyczajnej, z 16 wyłuszczarni pracujących
na terenie Polski w ciągu lat 2009-2012. Otwarte szyszki pozbawione nasion i traktowane jako odpad połuszczarski mogą być wykorzystane na cele energetyczne w lokalnych elektrowniach. Aby w tym celu można było je wykorzystać, należy na początek sprawdzić, ile rocznie pozyskuje się tego materiału. Zauważono dużą zmienność w dostarczaniu jednostek nasiennych do wyłuszczarni związaną z latami nasiennymi. Przez cztery analizowane lata najwięcej pozyskano szyszek sosny zwyczajnej ponad 1,3 tys. Mg, a najmniej jodły pospolitej - 31 Mg. Ze względu na stosunkowo małą masę pojedynczych szyszek i dużą objętość szyszki można transportować na niewielkie odległości. Do wyłuszczarni łuszczących najwięcej szyszek należą obiekty w Nadleśnictwach Jarocin, Kluczborki i Rytel, gdzie dostarczano łącznie 600 Mg szyszek rocznie. Po łuszczeniu szyszki zmniejszają swoją masę w zależności od gatunku od 16 do 30%. Analiza wykazała, że rocznie można wykorzystać na cele energetyczne średnio 270 Mg pustych szyszek. Szyszki traktowane jako odpad mogą być bezpośrednio spalane lub wykorzystane jako dodatek w produkcji brykietów i peletów
Testing for HIV Increases the Odds of Correct Fetal Ultrasound Result
Introduction: Infectious diseases during pregnancy may pose a threat to both mother and the developing fetus. It also creates an opportunity to screen for diseases being widely underdiagnosed among women in Poland, such as human immunodeficiency virus (HIV) or sexually transmitted infections (STI). Therefore, we aimed to assess the number of pregnant women that had not been tested for HIV despite the recommendations. In addition, a comparison of clinical evaluation between HIV-tested and non-tested pregnant women was also performed. Material and methods: Medical records of all consecutive pregnant women, referred to our Infectious Diseases Hospital between September 2019 and March 2020 were retrospectively analyzed. Implementation of recommended screening testing towards infectious diseases during pregnancy including human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV), syphilis, and rubella, were also analyzed. Results: Medical records of 273 women were included in the analysis. The median age was 32 years (interquartile range: 26–33 years). In total 243/273 (89.0%) had been tested for HIV as recommended, and the remaining 30/273 (11.0%) had not been tested. HIV infection was not confirmed in any of the participants. Only one woman within the HIV non-tested group had been correctly tested towards other infections during her pregnancy. The recommended full testing was more likely to be correctly implemented in women who had also been tested for HIV (171/243, 70.4% vs. 1/30, 3.3%, OR 68.9; 95% CI 9.2–515.3, p < 0.00001). Moreover, the correct fetal ultrasound result was more likely to be obtained in women who had been tested for HIV as recommended (234/243, 96.3% vs. 11/30, 36.7%, OR 44.9; 95% CI 16.6–121.8, p < 0.00001). Conclusions: Despite the law regulations, 11% of pregnant women referred to consultations to the infectious diseases center had not been tested for HIV. At the same time, correct fetal ultrasound results are more likely to occur in women tested for HIV according to recommendations. This suggests that a holistic approach to screening, both for communicable and non-communicable diseases, among pregnant women may translate to better pregnancy outcomes
Dependences of Mechanical Properties of Ceramics with Bimodal Pore Size Distribution on the Porosity at Various Scale Levels
Particle Size Distribution and Physicochemical Properties of Pellets Made of Straw, Hay, and Their Blends
Distribution of Trace Metals in Street Dusts and Tree Leaves and Their Source Identification in a Mid-Populated Anatolian City
Hepatite C e gestação: análise de fatores associados à transmissão vertical
INTRODUÇÃO: Informações sobre hepatite C durante a gestação em serviços brasileiros são escassas. O objetivo deste estudo foi verificar os fatores associados à transmissão vertical do vírus da hepatite C em gestantes. MÉTODOS: Estudo observacional, transversal, realizado em gestantes procedentes do município de Campo Grande/MS, que apresentaram sorologia reagente e confirmada para VHC, no período de 2002 a 2005. Considerou-se transmissão vertical sorologia VHC positiva por ELISA, confirmada com PCR, após os 18 meses de vida do recém-nascido. Considerou-se fatores associados a TV: tipo de parto, tempo de rotura de membranas, amamentação, histórico de transfusões sanguíneas prévias, uso de drogas ilícitas, número de parceiros sexuais e presença de tatuagens pelo corpo. RESULTADOS: Identificou-se 58 gestantes portadoras do VHC, revelando prevalência de infecção de 0,2% (58/31.187). Das 58 pacientes, 23 (39,6%) preencheram os critérios de inclusão no estudo. A taxa de TV foi de 13% (3/23), sendo os subtipos virais mais frequentes: 1a (53%), 1b (30%), 2b (4%) e 3a (13%). Duas (8,7%) pacientes apresentaram co-infecção pelo HIV. Houve associação (p < 0,05) entre TV e carga viral elevada (> 2,5x10(6)) e entre TV e uso de drogas ilícitas pela mãe (p < 0,05). CONCLUSÕES: O presente estudo demonstra que elevada viremia materna e o uso de drogas ilícitas pela mãe associam-se a transmissão materno-fetal do VHC