56 research outputs found

    Textile structures modeled on a spider's net

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    Innovative textile fabrics modelled on the structure of a spider web can find application in the reinforcing of composites in conditions of where a centrifugal force occurs, for example rotational discs. At the Institute of Architecture of Textile at the Technical University of Łódź research work is carried out on mechanised production of woven fabrics whose struc- ture is modelled on a spider webweb. The paper presents a review of textile techniques and technologies from the point of view of their usefulness for producing fabrics of a flat round net type structure modelled on the structure of a spider web.There is also an analysis of the mechanical properties of the different textile structures from the point of view of fulfilling the requirements to operate in conditions which are affected by a centrifugal force

    Influence of different kind of clothing material on selected cardiovascular, respiratory and psychomotor parameters during moderate physical exercise

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    Objectives: The aim of the experiment was to analyze the influence that the clothing material may have on human physiology and thermal comfort both at rest and physical effort to answer the question which fabric is better, a natural or a synthetic one. Materials and Methods: We measured some psychomotor parameters: critical flicker frequency (CFF), reaction time to auditory/visual stimuli (RT), concentration of attention (CA); cardiovascular parameters: blood pressure (BP), heart rate (HR) and respiratory parameters: tidal volume (VT), minute ventilation (VE), oxygen consumption (VO2), carbon dioxide output (VCO2), respiratory exchange ratio (RER) in human volunteers before, during and after physical effort. The subjects performed a 15-min treadmill test on treadmill wearing clothes made of two different materials: 100% coarse wool and 100% acrylic. An interview was conducted directly before the exercise test to assess the subjects' general mood and wellbeing on that day. Besides, before and after the test, the subjects in their own words described the sensation they felt with respect to the physiological comfort of particular clothing. Results: The results showed that wearing clothes made of different fabrics had some influence on the cardiovascular and respiratory parameters during physical effort but it did not have any effect on the psychomotor skills. The perception of physiological comfort by the subjects wearing coarse wool or acrylic depended on their physiological state and differed at rest and after the physical effort. Conclusions: The course of physiological processes depends on the kind of clothing a given person is wearing. It is not possible to clearly define which of the two clothing materials: natural — wool, or synthetic — acrylic is better. Each of them exerts a different effect on the human organism. The usefulness of a given type of clothing material seems to depend on the human physiological state and the related thermoregulatory processes

    The clinical usefulness of biochemical (free β-hCG, PAPP-A) and ultrasound (nuchal translucency) parameters in prenatal screening of trisomy 21 in the first trimester of pregnancy

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    Objectives: The aim of the study was to analyze the correlation of multiples of the normal median of PAPP-A, free β-hCG levels and nuchal translucency values in prenatal, first trimester screening of trisomy 21 in pregnant women.  Material and methods: 251 pregnant women underwent antenatal screening at 11–13+6 weeks of pregnancy which was composed of the measurement of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein (PAPP-A) levels in the maternal serum and an ultrasound assessment of nuchal translucency (NT). The pregnant women with a high risk of trisomy 21 (≥ 1:300) were given amniocentesis to verify fetal defects. There were 217 cases of normal fetal karyotype and 34 cases of trisomy 21. PAPP-A, β-hCGMoM and NT values were analyzed for the predefined ranges.  Results: 85% cases of trisomy 21 had elevated free β-hCGMoM ( > 1.5) and only 53% of these had a PAPP-AMoM result below 0.5 (p < 0.05). Analysis of NT in selected ranges of β-hCG ( > 1.5) and PAPP-AMoM ( < 0.05), which are typical for Down Syndrome values, showed that not all fetuses with Down Syndrome presented with an increased NT. Respectively 44.15% and 26.5% of fetuses presented with increased NT. Characteristic for trisomy 21, a correlation with all 1st trimester screening tests’ parameters occurred in only 23.5% of cases. In 53% of cases the results were atypical.  Conclusions: The PAPP-A and β-hCG values in the selected MoM ranges did not shown a correlation to the NT measurement, therefore they are independent factors in the diagnosis of trisomy 21. Simultaneous biochemical and ultrasound testing is an indispensable condition for prenatal diagnosis of trisomy 21 in the 1st trimester of pregnancy.

    Maternal factors, ultrasound and placental function parameters in early pregnancy as predictors of birth weight in low-risk populations and among patients with pre-gestational diabetes

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    Objectives: The aim of our work was to assess the usefulness of maternal factors, ultrasound and placental function parameters during early pregnancy as predictors of birth weight in populations of healthy pregnant women and women suffering from pregestational diabetes. Material and methods: A study group comprised 97 healthy women and 160 women with pregestational diabetes (PGDM, type 1), all in singleton pregnancy. Ultrasound examination was performed between weeks 11 and 14, and in weeks 20 and 30 of gestation, based on recommendations of the Polish Society of Gynecologists and Obstetricians, Ultrasonography Division. We also checked uterine artery blood flow parameters. During the first trimester consultation, all patients were surveyed and the following data were collected: age, BMI, reproductive history, comorbidities and smoking. We also collected blood samples and assessed PlGF, PAPP-A, and BhCG levels. Results: Our study showed that newborn birth weight negatively correlated with mother’s age, her diastolic blood pressure, PI of her uterine arteries and BhCG protein levels. Moreover, birth weight directly correlated with PlGF and PAPPA-A protein levels, and maternal early-pregnancy BMI. Conclusions: LGA diagnosis in the first trimester of pregnancy allows for selection and modification of some risk factors and closer monitoring of endangered fetuses throughout the pregnancy, with emphasis on the perinatal period. Parameters with confirmed usefulness in the prediction of birth weight in the first trimester included: maternal age, BMI, blood pressure, PAPP-A, BhCG and PlGF levels, fetal CRL and uterine artery PI

    Microwave-assisted synthesis and characterization of novel chitosan-based biomaterials for pelvic organ prolapse treatment

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    Pelvic organ disorders affect up to one in four women in the United States. The prevalence of pelvic organ prolapse (POP) is increasing with each year, particularly in the setting of prolonged life expectancy and an aging population. Current treatment approaches, including polypropylene monofilaments are associated with numerous painful and worrisome side-effects. Therefore, scientists are looking for new solutions. A promising alternative to the current treatment is tissue engineering, which can be utilized to re-create support to the vagina and pelvic organs. Tissue engineering requires the use of three-dimensional scaffolds, derived from biocompatible materials. Chitosan is a natural polymer, obtained from shellfish exoskeletons. It is known for its biodegradability, lack of cytotoxicity and non-pyrogenicity. Due to the presence of free hydroxyl and amino groups, it may undergo various modifications. In this paper, we describe a new type of chitosan-based biomaterials, which can be used as a new alternative scaffold that may provide support to prolapse organs. The chitosan scaffold was obtained under microwave radiation using multifunctional amino and organic acids. We discuss the scaffold's characteristics, with an emphasis on its chemical structure and morphology. Fourier transform infrared spectroscopy (FT-IR) analysis confirmed cross-linking processes with preservation of free amino groups. Moreover, mechanical durability, the stability and swelling ability of the scaffolds in a simulated body fluid were investigated. All of the prepared scaffolds demonstrated very good antioxidant activity and biodegradability. Importantly, the biocompatibility of chitosan scaffolds was examined on human vaginal VK2/E6E7 cell line. No evidence of toxicity was documented, and the cells maintained their presence on the studied materials. These results allude to the lack of toxicity of the scaffolds, and indicate that chitosan-based scaffold should be further investigated in in vivo studies as they may be a promising alternative treatment to pelvic organ prolapse.Web of Science70349147

    Mid-trimester ultrasound parameters for predicting birth weight in low risk pregnancies vs high-risk pregnancies complicated with pre-gestational diabetes mellitus

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    Objectives: The aim of the study was to assess the utility of mid-trimester ultrasound parameters in predicting birth weight in low-risk pregnancy and high-risk pregnancy complicated with pregestational diabetes mellitus. Material and methods: A study group comprised 97 healthy women and 160 women with pregestational diabetes (PGDM, type 1), all in singleton pregnancy. Ultrasound examination was performed between weeks 11 and 14, and in weeks 20 and 30 of gestation, based on recommendations of the Polish Society of Gynecologists and Obstetricians, Ultrasonography Division. We also checked uterine artery blood flow parameters. Results: There is a correlation between the birth weight and ultrasound-ascertained parameters, including those characterising uterine artery blood flow and foetal biometry [abdominal circumference (AC), femoral length (FL), biparietal dimension (BPD)].The biparietal dimension (BPD), head circumference (HC) abdominal circumference (AC) and pre-existing diabetes are the ultrasound predictors of LGA. The presence of an early-diastolic uterine artery blood flow waveform notching, as well as the uterine artery pulsatility index (UAPI), femoral length (FL) and hypertension in pregnancy are the ultrasound predictors of SGA. In the subset of women with pre-gestational diabetes (PGDM), there is a negative correlation between the birth weight and the uterine artery pulsatility index and early-diastolic uterine artery blood flow waveform notching. In women with pre-gestational diabetes mellitus (PGDM), femoral length (FL) is a significant predictor of LGA and in case of SGA significant predictors are uterine artery pulsatility index, artery blood flow waveform notching and femoral length (FL). Conclusions: Midtrimester ultrasound parameters with confirmed usefulness in the prediction of birth weight in low-risk pregnancy and high-risk pregnancy complicated with pregestational diabetes mellitus include: uterine artery PI, early-diastolic uterine artery blood flow waveform notching and foetal biometry

    Increased excitability of cortical neurons induced by associative learning: an ex vivo study

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    Abstract In adult mice, classical conditioning in which whisker stimulation is paired with an electric shock to the tail results in a decrease in the frequency of head movements, induces expansion of the cortical representation of stimulated vibrissae and enhances inhibitory synaptic interactions within the 'trained' barrels. We investigated whether such a simple associative learning paradigm also induced changes in neuronal excitability. Using whole-cell recordings from ex vivo slices of the barrel cortex we found that layer IV excitatory cells located in the cortical representation of the 'trained' row of vibrissae had a higher frequency of spikes recorded at threshold potential than neurons from the 'untrained' row and than cells from control animals. Additionally, excitatory cells within the 'trained' barrels were characterized by increased gain of the input-output function, lower amplitudes of fast after-hyperpolarization and decreased effect of blocking of BK channels by iberiotoxin. These findings provide new insight into the possible mechanism for enhanced intrinsic excitability of layer IV excitatory neurons. In contrast, the fast spiking inhibitory cells recorded in the same barrels did not change their intrinsic excitability after the conditioning procedure. The increased excitability of excitatory neurons within the 'trained' barrels may represent the counterpart of homeostatic plasticity, which parallels enhanced synaptic inhibition described previously. Together, the two mechanisms would contribute to increase the input selectivity within the conditioned cortical network

    How many biological replicates are needed in an RNA-seq experiment and which differential expression tool should you use?

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    An RNA-seq experiment with 48 biological replicates in each of 2 conditions was performed to determine the number of biological replicates (nrn_r) required, and to identify the most effective statistical analysis tools for identifying differential gene expression (DGE). When nr=3n_r=3, seven of the nine tools evaluated give true positive rates (TPR) of only 20 to 40 percent. For high fold-change genes (log2(FC)>2|log_{2}(FC)|\gt2) the TPR is >85\gt85 percent. Two tools performed poorly; over- or under-predicting the number of differentially expressed genes. Increasing replication gives a large increase in TPR when considering all DE genes but only a small increase for high fold-change genes. Achieving a TPR >85\gt85% across all fold-changes requires nr>20n_r\gt20. For future RNA-seq experiments these results suggest nr>6n_r\gt6, rising to nr>12n_r\gt12 when identifying DGE irrespective of fold-change is important. For 6<nr<126 \lt n_r \lt 12, superior TPR makes edgeR the leading tool tested. For nr12n_r \ge12, minimizing false positives is more important and DESeq outperforms the other tools.Comment: 21 Pages and 4 Figures in main text. 9 Figures in Supplement attached to PDF. Revision to correct a minor error in the abstrac

    Pantoea trifolii sp. nov., a novel bacterium isolated from Trifolium rubens root nodules

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    DATA AVAILABILITY : This article includes all the data generated or analyzed as part of this study. The strain MMK2T has been deposited in two bacterial collections: BCCM/LMG (LMG 33,049) and DSMZ (DSM 115,063). The MMK2T genome sequence has been deposited in NCBI under the accession number GCA_024506435.1 (genome assembly accession) and JANIET000000000.1 (Genbank accession). The 16S rDNA gene sequences of strains MMK2T and MMK3 have been deposited in NCBI under accession numbers OQ799602 and OQ799603.Please read abstract in the article.The National Centre for Research and Development, Poland and the National Research Foundation.https://www.nature.com/srephj2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyNon
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