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1.
J Environ Manage ; 356: 120618, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38508005

RESUMEN

Plastics introduced into the natural environment persist, degrade, and fragment into smaller particles due to various environmental factors. Microplastics (MPs) (ranging from 1 µm to 5 mm) and nanoplastics (NPs) (less than 1 µm) have emerged as pollutants posing a significant threat to all life forms on Earth. Easily ingested by living organisms, they lead to ongoing bioaccumulation and biomagnification. This review summarizes existing studies on the sources of MPs and NPs in various environments, highlighting their widespread presence in air, water, and soil. It primarily focuses on the sources, fate, degradation, fragmentation, transport, and ecotoxicity of MPs and NPs. The aim is to elucidate their harmful effects on marine organisms, soil biota, plants, mammals, and humans, thereby enhancing the understanding of the complex impacts of plastic particles on the environment. Additionally, this review highlights remediation technologies and global legislative and institutional measures for managing waste associated with MPs and NPs. It also shows that effectively combating plastic pollution requires the synergization of diverse management, monitoring strategies, and regulatory measures into a comprehensive policy framework.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Animales , Humanos , Microplásticos , Plásticos , Contaminación Ambiental , Suelo , Contaminantes Químicos del Agua/análisis , Mamíferos/metabolismo
2.
Mol Ecol ; 32(16): 4515-4530, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-35593303

RESUMEN

Ecologically distinct species may respond to landscape changes in different ways. In addition to basic ecological data, the extent of the geographic range has been successfully used as an indicator of species sensitivity to anthropogenic landscapes, with widespread species usually found to be less sensitive compared to range-restricted species. In this study, we investigate connectivity patterns of two closely related but ecologically distinct newt species - the range-restricted, Lissotriton montandoni and the widespread, L. vulgaris - using genomic data, a highly replicated setting (six geographic regions per species), and tools from landscape genetics. Our results show the importance of forest for connectivity in both species, but at the same time suggest differential use of forested habitat, with L. montandoni and L. vulgaris showing the highest connectivity at forest-core and forest-edges, respectively. Anthropogenic landscapes (i.e., higher crop- or urban-cover) increased resistance in both species, but the effect was one to three orders of magnitude stronger in L. montandoni than in L. vulgaris. This result is consistent with a view of L. vulgaris as an ecological generalist. Even so, currently, the negative impact of anthropogenic landscapes is mainly seen in connectivity among L. vulgaris populations, which show significantly stronger isolation and lower effective sizes relative to L. montandoni. Overall, this study emphasizes how habitat destruction is compromising genetic connectivity not only in endemic, range-restricted species of conservation concern but also in widespread generalist species, despite their comparatively lower sensitivity to anthropogenic landscape changes.


Asunto(s)
Ecosistema , Bosques , Animales , Salamandridae/genética
3.
Nanotechnology ; 34(41)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37343532

RESUMEN

In the current work, we report on the synthesizing of a series of novel nanocomposite materials obtained by functionalizing the SBA-15 silica matrix with anchored iron phosphonate molecules and the following thermal treatment. The obtained results reveal the formation of a unique amorphic layer of Fe-based compounds on the surface of silica walls of SBA-15 channels as a result of the organic groups' decomposition after moderate thermal treatment. Due to their unique structure, represented in an active Fe-containing amorphous coating spread over a large surface area, these materials are of great interest for their potential applications in fields such as catalysis, adsorption, and non-linear optics. The obtained materials remain amorphous, preserving the SBA-15 mesoporous structure up to temperatures of approximately 800 °C, after which the partial melting of the silica backbone is observed with the simultaneous formation of nanocrystals inside the newly-formed glassy mass. All obtained materials were characterized using such techniques as thermogravimetry, transmission and scanning electron microscopy combined with energy dispersive x-ray spectroscopy mapping, Raman spectroscopy, N2sorption analysis, x-ray diffraction, x-ray photoelectron spectroscopy, Mössbauer spectroscopy, and SQUID measurements.

4.
Int J Biometeorol ; 66(1): 139-148, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34618217

RESUMEN

Long-term and short-term changes in ambient temperature can cause stress in birds, leading to changes in the level of hematological parameters. The H:L ratio (heterophil-to-lymphocyte ratio) is a hematological index that allows for the assessment of the stress induced by environmental changes, including weather conditions. In this paper, we examined the influence of temperatures and the sum of precipitation on the health of nestling pied flycatchers (Ficedula hypoleuca) by using the H:L ratio reflecting the body's response to stress. All examined temperature indicators influenced the H:L ratio, yet the average value of daily minimum temperature during the first 12 days of nestling life had the strongest influence, maximum temperature had the weakest effect, while precipitation had no significant influence. Our research indicates that even a small increase in temperature caused a stress reaction in nestling pied flycatchers, which was reflected by an increase in the H:L ratio. The increase in the stress index (H:L ratio) was probably a result of poor weather conditions (precipitation, low temperature), which prevented the adult birds from actively foraging and properly feeding the nestlings.


Asunto(s)
Pájaros Cantores , Animales , Temperatura , Tiempo (Meteorología)
5.
Eur J Neurosci ; 53(8): 2639-2654, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33559232

RESUMEN

Reinforcement learning causes an action that yields a positive outcome more likely to be taken in the future. Here, we investigate how the time elapsed from an action affects subsequent decisions. Groups of C57BL6/J mice were housed in IntelliCages with access to water and chow ad libitum; they also had access to bottles with a reward: saccharin solution, alcohol, or a mixture of the two. The probability of receiving a reward in two of the cage corners changed between 0.9 and 0.3 every 48 hr over a period of ~33 days. As expected, in most animals, the odds of repeating a corner choice were increased if that choice was previously rewarded. Interestingly, the time elapsed from the previous choice also influenced the probability of repeating the choice, and this effect was independent of previous outcome. Behavioral data were fitted to a series of reinforcement learning models. Best fits were achieved when the reward prediction update was coupled with separate learning rates from positive and negative outcomes and additionally a "fictitious" update of the expected value of the nonselected choice. Additional inclusion of a time-dependent decay of the expected values improved the fit marginally in some cases.


Asunto(s)
Conducta de Elección , Recompensa , Animales , Toma de Decisiones , Aprendizaje , Ratones , Refuerzo en Psicología
6.
Int J Legal Med ; 135(6): 2175-2187, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34259936

RESUMEN

Increasing understanding of human genome variability allows for better use of the predictive potential of DNA. An obvious direct application is the prediction of the physical phenotypes. Significant success has been achieved, especially in predicting pigmentation characteristics, but the inference of some phenotypes is still challenging. In search of further improvements in predicting human eye colour, we conducted whole-exome (enriched in regulome) sequencing of 150 Polish samples to discover new markers. For this, we adopted quantitative characterization of eye colour phenotypes using high-resolution photographic images of the iris in combination with DIAT software analysis. An independent set of 849 samples was used for subsequent predictive modelling. Newly identified candidates and 114 additional literature-based selected SNPs, previously associated with pigmentation, and advanced machine learning algorithms were used. Whole-exome sequencing analysis found 27 previously unreported candidate SNP markers for eye colour. The highest overall prediction accuracies were achieved with LASSO-regularized and BIC-based selected regression models. A new candidate variant, rs2253104, located in the ARFIP2 gene and identified with the HyperLasso method, revealed predictive potential and was included in the best-performing regression models. Advanced machine learning approaches showed a significant increase in sensitivity of intermediate eye colour prediction (up to 39%) compared to 0% obtained for the original IrisPlex model. We identified a new potential predictor of eye colour and evaluated several widely used advanced machine learning algorithms in predictive analysis of this trait. Our results provide useful hints for developing future predictive models for eye colour in forensic and anthropological studies.


Asunto(s)
ADN , Color del Ojo , ADN/genética , Color del Ojo/genética , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple , Programas Informáticos
7.
Dis Aquat Organ ; 147: 1-12, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34734569

RESUMEN

Emerging infectious diseases are a threat to biodiversity and have taken a large toll on amphibian populations worldwide. The chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), and the iridovirus Ranavirus (Rv), are of concern as all have contributed to amphibian declines. In central and eastern Europe, their geographical and host distributions and main environmental drivers determining prevalence are poorly known. We screened over 1000 amphibians from natural and captive populations in Poland for the presence of Bd, Bsal and Rv. In wild amphibian populations, we found that Bd is widespread, present in 46 out of 115 sampled localities as well as 2 captive colonies, and relatively common with overall prevalence at 14.4% in 9 species. We found lower prevalence of Rv at 2.4%, present in 11 out of 92 sampling sites, with a taxonomic breadth of 8 different amphibian species. Bsal infection was not detected in any individuals. In natural populations, Pelophylax esculentus and Bombina variegata accounted for 75% of all Bd infections, suggesting a major role for these 2 species as pathogen reservoirs in Central European freshwater habitats. General linear models showed that climatic as well as landscape features are associated with Bd infection in Poland. We found that higher average annual temperature constrains Bd infection, while landscapes with numerous water bodies or artificial elements (a surrogate for urbanization) increase the chances of infection. Our results show that a combination of climatic and landscape variables may drive regional and local pathogen emergence.


Asunto(s)
Quitridiomicetos , Enfermedades Transmisibles Emergentes , Micosis , Anfibios , Animales , Anuros , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/veterinaria , Micosis/epidemiología , Micosis/veterinaria , Polonia/epidemiología
8.
Sensors (Basel) ; 21(19)2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34640768

RESUMEN

This paper presents a camera-based prototype sensor for detecting fatigue and drowsiness in drivers, which are common causes of road accidents. The evaluation of the detector operation involved eight professional truck drivers, who drove the truck simulator twice-i.e., when they were rested and drowsy. The Fatigue Symptoms Scales (FSS) questionnaire was used to assess subjectively perceived levels of fatigue, whereas the percentage of eye closure time (PERCLOS), eye closure duration (ECD), and frequency of eye closure (FEC) were selected as eye closure-associated fatigue indicators, determined from the images of drivers' faces captured by the sensor. Three alternative models for subjective fatigue were used to analyse the relationship between the raw score of the FSS questionnaire, and the eye closure-associated indicators were estimated. The results revealed that, in relation to the subjective assessment of fatigue, PERCLOS is a significant predictor of the changes observed in individual subjects during the performance of tasks, while ECD reflects the individual differences in subjective fatigue occurred both between drivers and in individual drivers between the 'rested' and 'drowsy' experimental conditions well. No relationship between the FEC index and the FSS state scale was found.


Asunto(s)
Conducción de Automóvil , Fatiga/diagnóstico , Humanos , Vehículos a Motor , Descanso , Vigilia
9.
Int J Mol Sci ; 22(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672302

RESUMEN

Plant-pollinator interactions significantly influence reproductive success (RS) and drive the evolution of pollination syndromes. In the context of RS, mainly the role of flower morphology is touched. The importance of nectar properties is less studied, despite its significance in pollination effectiveness. Therefore, the aim of this study was to test selection on flower morphology and nectar chemistry in the generalistic orchid Neottia ovata. In 2019-2020, we measured three floral displays and six flower traits, pollinaria removal (PR), female reproductive success (FRS), and determined the soil properties. The sugars and amino acids (AAs) were analyzed using the HPLC method. Data were analyzed using multiple statistical methods (boxplots, ternary plot, one-way ANOVA, Kruskal-Wallis test, and PCA). Variation of flower structure and nectar chemistry and their weak correlation with RS confirms the generalistic character of N. ovata. In particular populations, different traits were under selection. PR was high and similar in all populations in both years, while FRS was lower and varied among populations. Nectar was dominated by glucose, fructose, and included 28 AAs (Ala and Glu have the highest content). Sugars and AAs influenced mainly FRS. Among soil parameters, carbon and carbon:nitrogen ratio seems to be the most important in shaping flower structure and nectar chemistry.


Asunto(s)
Flores/anatomía & histología , Orchidaceae/anatomía & histología , Néctar de las Plantas/química , Adaptación Fisiológica , Aminoácidos/análisis , Animales , Ecosistema , Flores/fisiología , Orchidaceae/química , Orchidaceae/fisiología , Polonia , Polinización , Suelo/química , Análisis Espacio-Temporal , Azúcares/análisis
10.
BMC Genomics ; 21(1): 538, 2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32758128

RESUMEN

BACKGROUND: Greying of the hair is an obvious sign of human aging. In addition to age, sex- and ancestry-specific patterns of hair greying are also observed and the progression of greying may be affected by environmental factors. However, little is known about the genetic control of this process. This study aimed to assess the potential of genetic data to predict hair greying in a population of nearly 1000 individuals from Poland. RESULTS: The study involved whole-exome sequencing followed by targeted analysis of 378 exome-wide and literature-based selected SNPs. For the selection of predictors, the minimum redundancy maximum relevance (mRMRe) method was used, and then two prediction models were developed. The models included age, sex and 13 unique SNPs. Two SNPs of the highest mRMRe score included whole-exome identified KIF1A rs59733750 and previously linked with hair loss FGF5 rs7680591. The model for greying vs. no greying prediction achieved accuracy of cross-validated AUC = 0.873. In the 3-grade classification cross-validated AUC equalled 0.864 for no greying, 0.791 for mild greying and 0.875 for severe greying. Although these values present fairly accurate prediction, most of the prediction information was brought by age alone. Genetic variants explained < 10% of hair greying variation and the impact of particular SNPs on prediction accuracy was found to be small. CONCLUSIONS: The rate of changes in human progressive traits shows inter-individual variation, therefore they are perceived as biomarkers of the biological age of the organism. The knowledge on the mechanisms underlying phenotypic aging can be of special interest to the medicine, cosmetics industry and forensics. Our study improves the knowledge on the genetics underlying hair greying processes, presents prototype models for prediction and proves hair greying being genetically a very complex trait. Finally, we propose a four-step approach based on genetic and epigenetic data analysis allowing for i) sex determination; ii) genetic ancestry inference; iii) greying-associated SNPs assignment and iv) epigenetic age estimation, all needed for a final prediction of greying.


Asunto(s)
Exoma , Color del Cabello , Envejecimiento , ADN , Humanos , Cinesinas , Polimorfismo de Nucleótido Simple , Secuenciación del Exoma
11.
J Card Surg ; 35(11): 3153-3154, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32939864

RESUMEN

A coronary sinus (CS) interatrial connection is a rare congenital anomaly which can be in various types from atrial septal defect type unroofing CS to the total absence of the CS. The pathology usually accompanies the left superior caval vein (LSCV) draining to CS and in case of its absence directly to the left atrium (LA). We present a 53-year-old woman after surgical correction of a secundum atrial septal defect in 1974, with a CS interatrial connection and paroxysmal atrial fibrillation (PAF). She gave a history of PAF and was admitted to our clinic due to progressive exertional intolerance, peripheral edema, and mild hypoxia (SatO2 92%) with subsequent cyanosis. Transthoracic echocardiography showed a left-to-right shunt in the posteroinferior part of the atrial septum. Computed tomography revealed a persistent LSCV draining directly into the LA, the absence of the CS, and cardiac veins draining into the LA. The right atrium (RA) and the LA were connected via a tunnel with a visible contrast passage from the left to the right side-the persisting mouth of the coronary sinus. The patient was qualified for surgical correction. A glutaraldehyde-treated autologous pericardial patch was used to construct the tunnel connecting the LSVC and the RA. The second part of the patch was used to close the atrial communication at the inferior vena cava level. The patient had an uncomplicated postoperative course and is now classified in New York Heart Association Class II.


Asunto(s)
Seno Coronario/anomalías , Seno Coronario/diagnóstico por imagen , Defectos del Tabique Interatrial/cirugía , Fibrilación Atrial/etiología , Procedimientos Quirúrgicos Cardiovasculares/métodos , Seno Coronario/cirugía , Ecocardiografía , Femenino , Atrios Cardíacos/anomalías , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/cirugía , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Venas Cavas/anomalías , Venas Cavas/diagnóstico por imagen , Venas Cavas/cirugía
12.
Int J Biometeorol ; 64(4): 623-629, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31915916

RESUMEN

It has been suggested that extreme weather events may be treated as natural experiments that may unravel the mechanisms by which birds adjust their phenology and breeding parameters to environmental variability. In 2017, a sudden and heavy drop of temperatures for several days affected many European bird populations. This event occurred during the laying-early incubation period in the great tit (Parus major) population in central Poland, causing a large delay in hatching and had sustained reproductive consequences. This cold snap occurring once breeding activity had already started in 2017 was followed by the warm and invariable breeding season of 2018. This natural experiment had an essential influence on great tit reproductive parameters. We found a significant difference in hatching date, number of fledglings, hatching success, and fledging success between 2017 and 2018. In 2017, there were about two fledglings per nest fewer than in 2018. Fledging success was positively associated with hatching delay in 2017, while the relation was negative in 2018. Hatching success differed significantly between both years, being higher in 2018. Mean level of hemoglobin (used as index of body, physiological condition) in the blood of nestling great tits was higher in 2017 than in 2018. We argue that the moment of hatching may be (at least in some years) more tightly related to the moment of maximum food demand of tit nestlings than the traditionally used laying date. Also in extreme years, phenotypic plasticity of hatching delays may be insufficient to adjust the timing of breeding to the upcoming extreme weather events. Further examining its limits may be an important goal for future research.


Asunto(s)
Passeriformes , Animales , Femenino , Polonia , Reproducción , Estaciones del Año , Temperatura
13.
Int J Mol Sci ; 21(23)2020 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-33260340

RESUMEN

Herein, we propose newly designed and synthesized gold nanopeanuts (Au NPes) as supports for cisplatin (cPt) immobilization, dedicated to combined glioblastoma nano-chemo-radiotherapy. Au NPes offer a large active surface, which can be used for drugs immobilization. Transmission electron microscopy (TEM) revealed that the size of the synthesized Au NPes along the longitudinal axis is ~60 nm, while along the transverse axis ~20 nm. Raman, thermogravimetric analysis (TGA) and differential scanning calorimetry (DCS) measurements showed, that the created nanosystem is stable up to a temperature of 110 °C. MTT assay revealed, that the highest cell mortality was observed for cell lines subjected to nano-chemo-radiotherapy (20-55%). Hence, Au NPes with immobilized cPt (cPt@AuNPes) are a promising nanosystem to improve the therapeutic efficiency of combined nano-chemo-radiotherapy.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Cisplatino/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Oro/química , Nanopartículas del Metal/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Glioblastoma/patología , Humanos , Nanopartículas del Metal/ultraestructura , Espectrometría Raman
14.
Mol Ecol ; 28(21): 4798-4810, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31574568

RESUMEN

Variation in the vertebrate major histocompatibility complex (MHC) genes is crucial for fighting pathogen assault. Because new alleles confer a selective advantage, MHC should readily introgress between species, even under limited hybridization. Using replicated transects through two hybrid zones between strongly reproductively isolated European newts, Lissotriton montandoni and L. vulgaris, we demonstrated recent and ongoing MHC class I and II introgression in the Carpathian region. The extent of introgression correlated with the age of contact. In the older zone, MHC similarity between species within transects exceeded similarity between transects within species, implying pervasive introgression - a massive exchange of MHC genes, not limited to specific variants. In simulations, the observed pattern emerged under the combined action of balancing selection and hybridization, but not when these processes acted separately. Thus, massive introgression at advanced stages of divergence can introduce novel and restore previously lost MHC variation, boosting the adaptive potential of hybridizing taxa. In consequence, MHC genes may be the last to stop introgressing between incipient species.


Asunto(s)
Hibridación Genética/genética , Complejo Mayor de Histocompatibilidad/genética , Salamandridae/genética , Alelos , Animales , Flujo Génico/genética , Variación Genética/genética , Genética de Población/métodos , Selección Genética/genética
15.
Mol Ecol ; 28(21): 4811-4824, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31549466

RESUMEN

Genomic heterogeneity of divergence between hybridizing species may reflect heterogeneity of introgression, but also processes unrelated to hybridization. Heterogeneous introgression and its repeatability can be directly tested in natural hybrid zones by examining multiple transects. Here, we studied hybrid zones between the European newts Lissotriton montandoni and two lineages of Lissotriton vulgaris, with replicate transects within each zone. Over 1,000 nuclear genes located on a linkage map and mitochondrial DNA were investigated using geographical and genomic clines. Overall, the five transects were all similar, showing hallmarks of strong reproductive isolation: bimodal distribution of genotypes in central populations and narrow allele frequency clines. However, the extent of introgression differed between the zones, possibly as a consequence of their different ages, as suggested by the analysis of heterozygosity runs in diagnostic markers. In three transects genomic signatures of small-scale (~2 km) zone movements were detected. We found limited overlap of cline outliers between transects, and only weak evidence of stronger differentiation of introgression between zones than between transects within zones. Introgression was heterogeneous across linkage groups, with patterns of heterogeneity similar between transects and zones. Predefined candidates for increased or reduced introgression exhibited only a subtle tendency in the expected direction, suggesting that interspecific differentiation is not a reliable indicator for the strength of introgression. These hierarchically sampled hybrid zones of apparently different ages show how introgression unfolds with time and offer an excellent opportunity to dissect the dynamics of hybridization and architecture of reproductive isolation at advanced stages of speciation.


Asunto(s)
Hibridación Genética/genética , Salamandridae/genética , Animales , ADN Mitocondrial/genética , Flujo Génico/genética , Frecuencia de los Genes/genética , Marcadores Genéticos/genética , Especiación Genética , Genética de Población/métodos , Genoma/genética , Genotipo , Geografía , Aislamiento Reproductivo
16.
Front Zool ; 15: 34, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30305833

RESUMEN

BACKGROUND: Interspecies variation in avian egg shape and size is understandable in terms of adaptation, allometry and phylogeny. Within-species variation in egg properties influences offspring fitness and can be explained by differences in allocation of resources into reproductive components of life history in mulidimensionally variable environments. Egg size is inherently traded-off with clutch size, which may also be true of egg shape in some cases. We investigated long-term variation in egg shape and size between two geographically close populations of blue tits Cyanistes caeruleus in relation to clutch size and habitat differences. RESULTS: The main finding is that there exists a persistent long-lasting pattern of spatial variation of egg size and shape between the two study populations of blue tits, 10 km apart, controlling for clutch size. Eggs in the urban park site were on average larger in volume and less spherical in shape than eggs in the forest site over 12 years of this study. Egg sizes were negatively associated with clutch sizes. Egg shape was not correlated with clutch size. CONCLUSIONS: Our findings suggest that the pattern of variation in egg size and shape results from different trophic richness of the breeding habitats of the study populations, demanding different allocation of resources and, especially, from the contrasting difference in the availability of calcium.

17.
Eur J Appl Physiol ; 118(11): 2443-2454, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30171350

RESUMEN

PURPOSE: Brain hemodynamics is fundamental for the functioning of the human being. Many biophysical factors affect brain circulation, so that a satisfactory understanding of its behavior is challenging. We developed a mathematical model to simulate cerebral and extracerebral flows and pressures in humans. METHODS: The model is composed of an anatomically informed 1-D arterial network, and two 0-D networks of the cerebral circulation and brain drainage, respectively. It takes into account the pulse-wave transmission properties of the 55 main arteries and the main hydraulic and autoregulation mechanisms ensuring blood supply and drainage to the brain. Proper pressure outputs from the arterial 1-D model are used as input to the 0-D models, together with the contribution to venous pressure due to breathing that simulates the drainage effect of the thoracic pump. RESULTS: The model we developed is able to link the arterial tree with the venous pathways devoted to the brain drainage, and to simulate important factors affecting cerebral circulation both for physiological and pathological conditions, such as breathing and hypo/hypercapnia. Finally, the average value of simulated flows and pressures is in agreement with the available experimental data. CONCLUSIONS: The model has the potential to predict important clinical parameters before and after physiological and/or pathological changes.


Asunto(s)
Presión Sanguínea/fisiología , Circulación Cerebrovascular/fisiología , Hemodinámica/fisiología , Modelos Cardiovasculares , Arterias/fisiología , Simulación por Computador , Humanos
18.
Int J Biometeorol ; 62(8): 1437-1445, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29667035

RESUMEN

Variation in ambient temperature affects various life stages of organisms. It has been suggested that climate change not only implies higher global temperatures but also more unpredictable weather and more frequent extreme weather events. Temperature has a major influence on the optimal laying-incubation-hatching dates of insectivorous passerines, because it poses energetic constraints and affects the timing of food abundance. We have been studying breeding characteristics of great tits Parus major and blue tits Cyanistes caeruleus in two areas, an urban parkland and a deciduous forest, around the city of Lódz since 2002. During the egg-laying period in 2017, both tit species at both study areas faced an unusual cold spell as reflected by a sudden decrease in the mean ambient temperature to ca. 2-3 °C for about 5 days, which caused mean hatching delays of up to 6 days. Since flexibility of behavior plays a major role in adjusting to unpredictable weather conditions, examining its limits may be an important goal for future research.


Asunto(s)
Frío Extremo , Passeriformes , Reproducción , Animales , Europa (Continente) , Femenino , Óvulo , Polonia , Temperatura
19.
Environ Monit Assess ; 190(6): 338, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29748822

RESUMEN

Many freshwater ecosystems face severe threats from anthropogenic disturbances. In the field, we investigated the morphology of spring niches and the species richness of vascular plants and bryophytes in 16 springs, draining the quaternary aquifers, located in two different environments-an urban area (city of Bialystok) and a protected area (Knyszyn Forest Landscape Park, NE Poland). In total, 47 vascular plant and 45 bryophyte species were recorded, representing mostly crenophytes including protected species. The most important water quality parameters that can be used to evaluate variations of the spring water chemistry in NE Poland are the mineral-related parameters (electrolytic conductivity, Ca2+, SO42-, and Cl-). The organic-related parameters (DOC) and nutrients (TP, NO3--N) were negatively involved in water quality variations. Our results show that anthropogenic activity significantly affects the biodiversity of plant communities in lowland springs. The presence or absence of crenophytes and bryophytes is indicative of the ecological status of the groundwater outflow complexes.


Asunto(s)
Briófitas/clasificación , Monitoreo del Ambiente/métodos , Manantiales Naturales/análisis , Tracheophyta/clasificación , Calidad del Agua , Biodiversidad , Briófitas/metabolismo , Ciudades , Ecosistema , Polonia , Tracheophyta/metabolismo , Agua/análisis
20.
Pol J Radiol ; 83: e621-e626, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30800201

RESUMEN

PURPOSE: Caseous calcification is a relatively uncommon variant of calcification of the mitral annulus. The purpose of the study was to assess characteristic radiological features of caseous calcification of the mitral annulus (CCMA) using computed tomography (CT) and compare the usefulness of CT and transthoracic echocardiogram (TTE) in a diagnosis of CCMA. MATERIAL AND METHODS: Seventeen patients with CCMA, who underwent TTE and CT, were analysed. The following features of CCMA were evaluated: location, size, attenuation, enhancement after contrast administration, and margins. RESULTS: In all cases TTE visualised an echo-dense structure with an irregular appearance involving the mitral valve annulus. In five cases the acoustic shadowing artefact was visible, and in four cases the mass contained central areas of echolucency. Eleven patients had valve disease.On CT CCMA appeared as a round mass in one case, in 10 cases as an oval mass, and in six patients it had a semilunar shape.In all cases on unenhanced CT, CCMA appeared as a hyperdense mass. On enhanced CT, CCMA in 10 cases (58.8%) had a hypodense centre, and in 7seven (41.2%) it had a hyperdense centre without enhancement after contrast administration. A hyperdense rim was observed in all cases except one patient. CONCLUSIONS: In cases of the atypical appearance of CCMA on TTE, CT can lead to a definitive diagnosis. The combination of unenhanced CT and after IV contrast administration scans allows for recognition and distinction of CCMA from other pathologies, while TTE allows for assessment of additional valve dysfunction.

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