983 research outputs found
Effect of Meteorological Conditions and Anthropogenic Factors on Air Concentrations of PM2.5 and PM10 Particulates on the Examples of the City of Kielce, Poland
The paper analyzes the influence of meteorological conditions (air temperature, wind speed, humidity, visibility) and anthropogenic factors (population in cities and in rural areas, road length, number of vehicles, emission of dusts and gases, coal consumption in industrial plants, number of air purification devices installed in industrial plants) on the concentration of PM2.5 and PM10 dusts in the air in the region of Kielce city in Poland. Spearman correlation coefficient was used to evaluate the relationship between the mentioned independent variables and air quality indicators. The calculated values of the correlation coefficient showed statistically significant relationships between air quality and the amount of installed air purification equipment in industrial plants. A statistically significant effect of the population in rural settlement units on the increase in air concentrations of PM2.5 and PM10 was also found, which proves the influence of the so-called low emission of pollutants on the air quality in the studied region. The analyses also revealed a statistically significant effect of road length on the decrease in PM2.5 and PM10 air content. This result indicates that a decrease in traffic intensity on particular road sections leads to an improvement in air quality. The analyses showed that despite the progressing anthropopression in the Kielce city region the air quality with respect to PM2.5 and PM10 content is improving. To verify the results obtained from statistical calculations, parametric models were also determined to predict PM2.5 and PM10 concentrations in the air, using the methods of Random Forests (RF), Boosted Trees (BT) and Support Vector Machines (SVM) for comparison purposes. The modelling results confirmed the conclusions that had been made based on previous statistical calculations
Pulsating B-type stars in the young open cluster h Persei (NGC 869)
We announce the discovery of six Beta Cephei stars and many other variable
stars in the young open cluster h Persei (NGC 869). The cluster seems to be
very rich in variable B-type stars, similarly to its twin, Chi Persei (NGC
884).Comment: 5 pages, 5 figures, Proc. HELAS-II conference, Goettingen, 20-24
August 200
Immobilization of Yeast on Polymeric Supports
Biocatalysts (enzymes and whole cells) play a crucial role in industrial processes allowing for efficient production of many important compounds, but their use has been limited because of the considerably unstable nature of enzymes. Immobilization often
protects enzymes from environmental stresses such as pH, temperature, salts, solvents, inhibitors and poisons. Immobilization of cells containing specific enzymes has further advantages such as elimination of long and expensive procedures for enzymes separation
and purification and it is vital to expand their application by enabling easy separation and purification of products from reaction mixtures and efficient recovery of catalyst. This review focuses on organic polymers (natural and synthetic) used as matrices for immobilization
of microorganisms, mainly baker’s yeasts and potential application of immobilized cells in the chemical, pharmaceutical, biomedical and food industries
Using lateral substitution to control conformational preference and phase behaviour of benzanilide-based liquid crystal dimers
Open access via the Wiley Agreement Funder: National Science Centre. Grant Number: 2021/43/B/ST5/00240 Acknowledgments D.P. gratefully acknowledges financial support from the National Science Centre (Poland) under the grant no. 2021/43/B/ST5/00240.Peer reviewedPublisher PD
Odnowa miast w świetle zrównoważonego rozwoju
W artykule przedstawiono współczesne problemy, z jakimi musi się zmierzyć planowanie przestrzenne i urbanistykę oraz podejmowane rozwiązania przy uwzględnieniu idei reurbanizacji i zrównoważonego rozwoju
Prenatal exposure to fine particles and polycyclic aromatic hydrocarbons and birth outcomes : a two-pollutant approach
Background Previous epidemiologic studies have considered
the effects of individual air pollutants on birth outcomes,
whereas a multiple-pollutant approach is more relevant
to public health policy.
Objectives The present study compared the observed
effect sizes of prenatal fine particulate matter (
PM2.5) and
polycyclic aromatic hydrocarbons (PAH) (a component of
PM2.5)
exposures on birth outcome deficits, assessed by the
single vs. two-pollutant approaches.
Methods The study sample included 455 term infants
born in Krakow to non-smoking mothers, among whom
personal exposures to PM2.5
and PAH were monitored in
the second trimester of pregnancy. The exposure effect
estimates (unstandardized and standardized regression
coefficients) on birth outcomes were determined using evant
covariates.
Results In the single-pollutant approach, each pollutant
was inversely associated with all birth outcomes. The effect
size of prenatal PAH exposure on birth weight and length
was twice that of PM2.5,
in terms of standardized coefficients.
In the two-pollutant approach, the negative effect of
PM2.5
on birth weight and length, adjusted for PAH exposure,
lost its significance. The standardized effect of PAH
on birth weight was 10-fold stronger ( = -0.20, = 0.004)
than that estimated for PM2.5
( = -0.02, = 0.757).
Conclusion The results provide evidence that PAH had a
greater impact on several measures of fetal development,
especially birth weight, than PM2.5.
Though in the singlepollutant
models PM2.5
had a significant impact on birth
outcomes, this effect appears to be mediated by PAH
Effect of three common SNPs in 5′-flanking region of LEP and ADIPOQ genes on their expression in Polish obese children and adolescents
Genes encoding adipokines are considered as candidates for human obesity. In this study we analyzed the expression of leptin (LEP) and adiponectin (ADIPOQ) genes in relation to common 5′-flanking or 5′UTR variants: -2548G>A (LEP), 19A>G (LEP) and -11377C>G (ADIPOQ) in Polish obese children and adolescents. Relative transcription levels in the subcutaneous adipose tissue (real time RT–PCR) and serum protein concentrations (RIA) were measured in 48 obese subjects with known genotypes at three polymorphic sites and in five non-obese controls. None of the studied polymorphisms altered significantly the expression. Significantly elevated relative transcription levels of the LEP gene (P < 0.05) and serum leptin concentrations (P < 0.01) were recorded in obese patients, when compared with the non-obese controls, but such differences were not found for the ADIPOQ gene. Interestingly, the leptin to adiponectin protein concentration ratio (L/A) was approximately sevenfold higher in obese children and adolescents when compared with the non-obese controls (P < 0.001). Taking into consideration the observed relationship between the genotypes and the gene expression level we suggest that these SNPs are not conclusive markers for predisposition to obesity in Polish children and adolescents. On the other hand, we confirmed that the leptin to adiponectin gene expression ratio (L/A) is an informative index characterizing obesity
Controlling spontaneous chirality in achiral materials : liquid crystal oligomers and the heliconical twist-bend nematic phase
Peer reviewedPublisher PD
Loss of Prestin Does Not Alter the Development of Auditory Cortical Dendritic Spines
Disturbance of sensory input during development can have disastrous effects on the development of sensory cortical areas. To examine how moderate perturbations of hearing can impact the development of primary auditory cortex, we examined markers of excitatory synapses in mice who lacked prestin, a protein responsible for somatic electromotility of cochlear outer hair cells. While auditory brain stem responses of these mice show an approximately 40 dB increase in threshold, we found that loss of prestin produced no changes in spine density or morphological characteristics on apical dendrites of cortical layer 5 pyramidal neurons. PSD-95 immunostaining also showed no changes in overall excitatory synapse density. Surprisingly, behavioral assessments of auditory function using the acoustic startle response showed only modest changes in prestin KO animals. These results suggest that moderate developmental hearing deficits produce minor changes in the excitatory connectivity of layer 5 neurons of primary auditory cortex and surprisingly mild auditory behavioral deficits in the startle response
- …