Number of results to display per page
Search Results
182. Brain fluid channels for metabolite removal
- Creator:
- Maloveská, Marcela, Humeník, Filip, Vikartovská, Zuzana, Hudáková, Nikola, Almášiová, Viera, Krešáková, Lenka, and Čížková, Daša
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brain ISF, CSF, meningeal lymphatics, and lymphatic drainage
- Language:
- English
- Description:
- The adult human brain represents only 2 % of the body's total weight, however it is one of the most metabolically active organs in the mammalian body. Its high metabolic activity necessitates an efficacious waste clearance system. Besides the blood, there are two fluids closely linked to the brain and spinal cord drainage system: interstitial fluid (ISF) and cerebrospinal fluid (CSF). The aim of this review is to summarize the latest research clarifying the channels of metabolite removal by fluids from brain tissue, subarachnoid space (SAS) and brain dura (BD). Special attention is focused on lymphatic vascular structures in the brain dura, their localizations within the meninges, morphological properties and topographic anatomy. The review ends with an account of the consequences of brain lymphatic drainage failure. Knowledge of the physiological state of the clearance system is crucial in order to understand the changes related to impaired brain drainage.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
183. Brown fat activity determined by infrared thermography and thermogenesis measurement using whole body calorimetry (BRIGHT Study)
- Creator:
- Tay, Shi Huan, Goh, Hui Jen, Govindharajulu, Priya, Cheng, Jierong, Camps, Stefan Gerardus Joseph Anna, Haldar, Sumanto, Velan, Sambasivam Sendhil, Sun, Lei, Li, Yiqun, Henry, Christiani Jeyakumar, and Leow, Melvin Khee-Shing
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brown adipose tissue, infrared thermography, calorimetry, thermogenesis, and automation
- Language:
- English
- Description:
- To assess BAT activity in humans at a population level, infrared thermography (IRT) represents a safe, readily repeatable and affordable alternative to 18F-FDG-PET. Building upon a previously proposed method by our laboratory, we further refined the image computational algorithm to quantify BAT activation in the cervical-supraclavicular (C-SCV) region of healthy young men under thermo-neutral and cold exposure conditions. Additionally, we validated the whole-body calorimeter (WBC) in reliably measuring cold-induced thermogenesis. The temperature gradient between C-SCV-deltoid regions, and the corresponding difference in heat power output, increased upon cold air exposure relative to thermo-neutral conditions (by 74.88 %, p<0.0001; and by 71.34 %, p<0.0001 respectively). Resting and cumulative energy expenditure (EE) rose significantly (by 13.14 % and 9.12 % respectively, p=0.0001) while positive correlations between IRT measures and EE were found with cold air exposure (percentage change in heat power gradient between ROI and deltoid, cold air: r2 =0.29, p=0.026, Pearson's correlation). IRT and WBC can be used to study BAT activation. The refined algorithm allows for more automation and objectivity in IRT data analysis, especially under cold air exposures.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
184. Bruno Bettelheim: Lidé nejsou mravenci. Postřehy psychoanalytika z koncentračního tábora
- Creator:
- Preiss, Marek
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
185. Burial-induced changes in the seed preferences of carabid beetles (Coleoptera: Carabidae)
- Creator:
- Saska, Pavel, Honěk, Alois, Foffová, Hana, and Martinková, Zdenka
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Carabidae, food preferences, granivory, seed consumption, seed burial, and weeds
- Language:
- English
- Description:
- Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids (Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus rufi pes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affi nis. The seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed of particular species were correlated only in P. rufi pes and A. littorea. We measured the seed characteristics (mass and viability) likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related to changes in any of these characteristics. This fi nding indicates that factors responsible for variation in seed acceptability are complex. This study provides the fi rst conclusive evidence that invertebrate seed predators will feed on seeds from seed banks, although they prefer fresh seeds.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
186. Calibration of an Arduino-based low-cost capacitive soil moisture sensor for smart agriculture
- Creator:
- Kulmány, István Mihály, Bede-Fazekas, Ákos, Beslin, Ana, Giczi, Zsolt, Milics, Gábor, Kovács, Barna, Kovács, Márk, Ambrus, Bálint, Bede, László, and Vona, Viktória
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- IoT, precision agriculture, low-cost capacitive soil moisture sensor, thermo-gravimetric method, repeatability and reproducibility study, and non-linear regression
- Language:
- Slovak
- Description:
- Agriculture faces several challenges to use the available resources in a more environmentally sustainable manner. One of the most significant is to develop sustainable water management. The modern Internet of Things (IoT) techniques with real-time data collection and visualisation can play an important role in monitoring the readily available moisture in the soil. An automated Arduino-based low-cost capacitive soil moisture sensor has been calibrated and developed for data acquisition. A sensor- and soil-specific calibration was performed for the soil moisture sensors (SKU:SEN0193 - DFROBOT, Shanghai, China). A Repeatability and Reproducibility study was conducted by range of mean methods on clay loam, sandy loam and silt loam soil textures. The calibration process was based on the data provided by the capacitive sensors and the continuously and parallelly measured soil moisture content by the thermo-gravimetric method. It can be stated that the response of the sensors to changes in soil moisture differs from each other, which was also greatly influenced by different soil textures. Therefore, the calibration according to soil texture was required to ensure adequate measurement accuracy. After the calibration, it was found that a polynomial calibration function (R2 ≥ 0.89) was the most appropriate way for modelling the behaviour of the sensors at different soil textures.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
187. Camarochiloides weiweii gen. n. & sp. n., the first representative of Pachynomidae (Hemiptera: Heteroptera) from Borneo
- Creator:
- Chen, Zhuo , Liu, Yingqi , Li, Hu, and Cai, Wanzhi
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Hemiptera, Heteroptera, Pachynomidae, Pachynominae, Camarochiloides weiweii, new genus, new species, Oriental Region, and Borneo
- Language:
- English
- Description:
- The family Pachynomidae is recorded from Borneo as well as Southeast Asia for the first time. Camarochiloides gen. n. and its type species C. weiweii sp. n. is described. Dorsal habitus and various morphological characters of the new species are illustrated. Subfamily placement and affinities of the new genus are briefly discussed, a key to the genera of Pachynominae is provided. Body and wing polymorphism and nymphal morphology of the new species are documented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
188. Camouflage in arid environments: the case of Sahara-Sahel desert rodents
- Creator:
- Nokelainen, Ossi, Sreelatha, Lekshmi B., Brito, José Carlos, Campos, João C., Scott-Samuel, Nicholas E., Valkonen, Janne K., and Boratyński, Zbyszek
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Africa, background matching, crypsis, predation, and protective colouration
- Language:
- English
- Description:
- Deserts and semi-deserts, such as the Sahara-Sahel region in North Africa, are exposed environments with restricted vegetation coverage. Due to limited physical surface structures, these open areas provide a promising ecosystem to understand selection for crypsis. Here, we review knowledge on camouflage adaptation in the Sahara-Sahel rodent community, which represents one of the best documented cases of phenotype-environment convergence comprising a marked taxonomic diversity. Through their evolutionary history, several rodent species from the Sahara-Sahel have repeatedly evolved an accurate background matching against visually-guided predators. Top-down selection by predators is therefore assumed to drive the evolution of a generalist, or compromise, camouflage strategy in these rodents. Spanning a large biogeographic extent and surviving repeated climatic shifts, the community faces extreme and heterogeneous selective pressures, allowing formulation of testable ecological hypotheses. Consequently, Sahara-Sahel rodents poses an exceptional system to investigate which adaptations facilitate species persistence in a mosaic of habitats undergoing climatic change. Studies of these widely distributed communities permits general conclusions about the processes driving adaptation and can give insights into how diversity evolves.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
189. Can chlorophyll fluorescence imaging make the invisible visible?
- Creator:
- Valcke, R.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- zpracování obrazu, stres (fyziologie), image processing, stress (physiology), chlorophyll fluorescence imaging, hyperspectral imaging, multicolour fluorescence imaging, thermal imaging, 2, and 581
- Language:
- Multiple languages
- Description:
- Chlorophyll fluorescence has developed into a well-established noninvasive technique to study photosynthesis and by extension, the physiology of plants and algae. The versatility of the fluorescence analysis has been improved significantly due to advancements in the technology of light sources, detectors, and data handling. This allowed the development of an instrumention that is effective, easy to handle, and affordable. Several of these techniques rely on point measurements. However, the response of plants to environmental stresses is heterogeneous, both spatially and temporally. Beside the nonimaging systems, low- and high-resolution imaging systems have been developed and are in use as real-time, multi-channel fluorometers to investigate heterogeneous patterns of photosynthetic performance of leaves and algae. This review will revise in several paragraphs the current status of chlorophyll fluorescence imaging, in exploring photosynthetic features to evaluate the physiological response of plant organisms in different domains. In the conclusion paragraph, an attempt will be made to answer the question posed in the title., R. Valcke., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
190. Can prenatal methamphetamine exposure be considered a good animal model for ADHD?
- Creator:
- Ochozková, Anna, Mihalčíková, Lýdia, Yamamotová, Anna, and Šlamberová, Romana
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- methamphetamine, hypoxia, ADHD, prenatal exposure, memory, OLT, and NORT
- Language:
- English
- Description:
- Attention-deficit/hyperactivity disorder (ADHD) is a mental disorder with a heterogeneous origin with a global incidence that continues to grow. Its causes and pathophysiological mechanisms are not fully understood. It includes a combination of persistent symptoms such as difficulty in concentration, hyperactivity and impulsive behavior. Maternal methamphetamine (MA) abuse is a serious problem worldwide, it can lead to behavioral changes in their offspring that have similarities with behavioral changes seen in children with ADHD. There are several types of ADHD animal models, e.g. genetic models, pharmacologically, chemically and exogenously induced models. One of the exogenously induced ADHD models is the hypoxia-induced model. Our studies, as well as those of others, have demonstrated that maternal MA exposure can lead to abnormalities in the placenta and umbilical cord that result in prenatal hypoxia as well as fetal malnutrition that can result in irreversible changes to experimental animals. Therefore, the aim the present study was to compare the cognitive impairments in MA exposure model with those in established model of ADHD – prenatal hypoxia model, to test whether MA exposure is a valid model of ADHD. Pregnant Wistar rats were divided into four groups based on their gestational exposure to MA: (1) daily subcutaneous injections of MA (5 mg/kg), (2) saline injections at the same time and volume, (3) daily 1-hr hypoxia (10 % O2), and (4) no gestational exposure (controls). Male rat offspring were tested for short-term memory in the Novel Object Recognition Test and the Object Location Test between postnatal days 35 and 40. Also their locomotor activity in both tests was measured. Based on the present results, it seems that prenatal MA exposure is not the best animal model for ADHD since it shows corresponding symptoms only in certain measures. Given our previous results supporting our hypothesis, more experiments are needed to further test possible use of prenatal MA exposure as an animal model of the ADHD.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public