820 research outputs found
Geluidmonitor 2014
Het RIVM heeft in 2013 geluidmetingen verricht op 23 locaties langs rijkswegen en op 26 locaties langs spoorwegen. Langs rijkswegen bleek het gemiddelde geluidniveau substantieel (2,4 decibel) hoger te liggen dan de berekende waarde. Langs het spoor was er gemiddeld geen significant verschil (0,5 dB). Afhankelijk van de meetlocatie kunnen de verschillen groter of kleiner zijn. De verschillen langs rijkswegen worden veroorzaakt door het feit dat de wettelijk voorgeschreven rekenmethode uitgaat van stille banden op een droog wegdek bij een standaardtemperatuur van 20 graden Celsius. De omstandigheden zijn vaak ongunstiger. Daarnaast draagt de variatie in akoestische kwaliteit van het wegdek bij aan de verschillen. Het meetprogramma vloeit voort uit een motie van de Tweede Kamer naar aanleiding van geluidwetgeving uit 2012. De wet stelt grenswaarden aan het geluid langs rijkswegen en spoorwegen. De wegen spoorbeheerder (Rijkswaterstaat en ProRail) dienen met een jaarlijkse berekening aan te tonen hieraan te voldoen. Onderdeel van de wet is ook een validatie van de rekenuitkomsten met metingen. Het RIVM verricht hiertoe jaarlijks geluidmetingen en vergelijkt die met de berekende geluidproductie die de weg- en spoorbeheerder rapporteren. Dit rapport gaat in op de verschillen tussen reken en meetresultaten in 2013. Het rapport geeft ook de meetresultaten uit 2014 langs rijkswegen en spoorwegen op 92 meetlocaties. Deze zullen worden vergeleken met de rekenresultaten die door de weg- en spoorbeheerder gepubliceerd worden in september 2015. Hierover zal het RIVM in 2016 rapporteren. Als blijkt dat de verschillen tussen de meet- en rekenwaarden structureel zijn, is nader onderzoek nodig naar de gezondheidskundige relevantie voor de Nederlandse bevolking en naar de vraag of aanpassingen van de rekenmethode nodig zijn.In 2013 RIVM has conducted noise measurements at 23 locations along motorways and at 26 locations along railways. Along motorways, the average measured noise level was substantially (2,4 dB) higher than the calculated value. Along the track, on average no significant difference was found (0,5 dB). Depending on the measurement location, larger or smaller differences can be found. The differences along motorways are partly due to the calculation method, which is based on low-noise tires on dry surfaces at a standard temperature of 20 degrees Celsius. The average conditions are less favorable. Also the variation in acoustic quality of the road surface contributes to the differences. For rail, no clear causes of differences are yet to be declared. The measurement program stems from a motion of the House in response to noise legislation (Swung) proposed and accepted in 2012. This Act sets limits on noise along motorways and railways. The administrators, Rijkswaterstaat and ProRail, annually demonstrate by a statutory calculation to fulfill this requirement. The legislation also requires validation of the calculation results by measurements. To this aim RIVM annually conducts measurements and compares the results with the calculated noise production as reported by the road- and railway administrator. This report discusses the differences between calculation and measurement results in 2013. It also contains the measurement results from 2014, along motorways and railroads on a sample of 92 measuring sites. These results will be compared with the calculation results, after they are published in September 2015 by the road- and railway administrator. If it appears that the differences between measurement and calculation are structural, further research is needed into the health implications for the Dutch population and whether adjustments to the calculation methods are needed.Ministerie van I&
DMSO-free methods of preserving mesenchymal stem cells (MSCs) that retain high levels of post thaw function
A novel, biologically-inspired strategy was developed to improve the preservation of mesenchymal stem cells (MSCs). MSCs are being investigated for the treatment of cardiovascular disorders, diabetes, connective tissue disorders, acute lung injury, amyotrophic lateral sclerosis, kidney diseases and more. To date, over 300 clinical trials involve the use of MSCs, with well over 2000 patients safely treated.Current methods of preserving MSCs are inadequate/ suboptimal. Concerns over poor post thaw function have become so pervasive that it is now common for MSCs to be cultured for 24-72 h prior to administration. These MSCs have a short shelf life (\u3c 24 hours), require special FDA permission, and the process increases cost and reduces access.
The research described here utilizes an evolutionary algorithm to identify combinations of naturally occurring osmolytes that yield high cell recovery post thaw and optimize the composition of a DMSO-free, protein-free medium for cryopreservation of the cells. Additionally, we demonstrate that these novel solutions maintain MSC functionality when evaluated using surface markers, attachment, proliferation, actin alignment, RNA expression, and DNA hydroxymethlyation.
Please click Additional Files below to see the full abstract
Longitudinal Trajectories of Gestational Thyroid Function: A New Approach to Better Understand Changes in Thyroid Function
Context Most studies of thyroid function changes during pregnancy use a cross-sectional design comparing means between groups rather than similarities within groups. Objective Latent class growth analysis (LCGA) is a novel approach to investigate longitudinal changes that provide dynamic understanding of the relationship between thyroid status and advancing pregnancy. Design Prospective observational study with repeated assessments. Setting General community. Patients Eleven hundred healthy women were included at 12 weeks’ gestation. Main Outcome Measures The existence of both free T4 (fT4) and TSH trajectories throughout pregnancy determined by LCGA. Results LCGA revealed three trajectory classes. Class 1 (n = 1019; 92.4%), a low increasing TSH reference group, had a gradual increase in TSH throughout gestation (from 1.1 to 1.3 IU/L). Class 2 (n = 30; 2.8%), a high increasing TSH group, displayed the largest increase in TSH (from 1.9 to 3.3 IU/L). Class 3 (n = 51; 4.6%), a decreasing TSH group, had the largest fall in TSH (from 3.2 to 2.4 IU/L). Subclinical hypothyroidism at 12 weeks occurred in up to 60% of class 3 women and was accompanied by elevated thyroid peroxidase antibodies (TPO-Ab) titers (50%) and a parental history of thyroid dysfunction (23%). In class 2, 70% of women were nulliparous compared with 46% in class 1 and 49% in class 3. Conclusions LCGA revealed distinct trajectories of longitudinal changes in fT4 and TSH levels during pregnancy in 7.4% of women. These trajectories were correlated with parity and TPO-Ab status and followed patterns that might reflect differences in pregnancy-specific immune tolerance between nulliparous and multiparous women
Possible relevance of pigeons as an indicator species for monitoring air pollution.
Wild city pigeons were caught at four different locations in the Netherlands to represent areas of high (Amsterdam-high), moderate (Amsterdam-medium), and low (Maastricht and Assen) traffic density. It is assumed that local ambient air pollution decreases as a function of traffic density. In these pigeons levels of polycyclic aromatic hydrocarbon (PAH)-DNA adducts, oxidative DNA damage, and heavy metal residues were determined in kidney, lung, liver, and blood (no adduct analysis in blood). The contribution of leaded gasoline to total body lead content was estimated by measuring concentrations of Pb and its isotopes in blood. We also analyzed samples of ambient air particulate matter for PAH and heavy metal concentrations at the four different locations. Interregional differences in heavy metals in ambient air particulate matter were reflected relatively well by pigeon body loads. The higher lead and cadmium concentrations in blood, kidney, liver, and lung were found in the Amsterdam high traffic density area, followed by Amsterdam medium, Assen, and Maastricht. A high Pb concentration in blood coincided with relatively low 206Pb/207Pb values, indicating a high contribution of leaded gasoline to total blood Pb concentrations in pigeons from the Amsterdam high traffic density area. Significantly enhanced blood zinc values were found in pigeons from both locations in Amsterdam compared to pigeons from the other two areas. However, no differences in Zn tissue levels between the four different groups were found. Oxidative DNA damage, determined as the ratio of 7-Hydro-8-oxo-2'-deoxyguanosine/ deoxyguanosine, in pigeon liver was highest in Amsterdam-high, followed by Assen (low traffic density). Pb content, but not the Cd content, was positively associated with oxidative DNA damage in liver tissue. In lung tissue, a negative correlation was found between oxidative DNA damage and Zn content. These results indicate that the carcinogenic potential of Pb might be ascribed to oxygen radical formation, whereas Zn plays a protective role against oxidative DNA damage. Places with high and medium traffic density could be clearly discriminated on the basis of PAH levels in the ambient air. The PAH content in particulate air samples was not, however, reflected in total PAH-related DNA adduct levels because no differences could be observed in tissue adduct levels in pigeons from the four different locations. Our results indicate that wild city pigeons can be used as biological indicators of exposure to heavy metal pollution in outdoor air
Vulnerability in acquisition, language impairments in Dutch: Creating a VALID data archive
The VALID Data Archive is an open multimedia data archive (under construction) with data from speakers suffering from language impairments. We report on a pilot project in the CLARIN-NL framework in which five data resources were curated. For all data sets concerned, written informed consent from the participants or their caretakers has been obtained. All materials were anonymized. The audio files were converted into wav (linear PCM) files and the transcriptions into CHAT or ELAN format. Research data that consisted of test, SPSS and Excel files were documented and converted into CSV files. All data sets obtained appropriate CMDI metadata files. A new CMDI metadata profile for this type of data resources was established and care was taken that ISOcat metadata categories were used to optimize interoperability. After curation all data are deposited at the Max Planck Institute for Psycholinguistics Nijmegen where persistent identifiers are linked to all resources. The content of the transcriptions in CHAT and plain text format can be searched with the TROVA search engin
- …