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The rapidly changing global climate due to increased emission of anthropogenic greenhouse gases (GHGs) is leading to an increased occurrence of extreme weather events such as droughts, floods, and heatwaves. The three major GHGs are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The major natural sources of CO2 include ocean–atmosphere exchange, respiration of animals, soils (microbial respiration) and plants, and volcanic eruption; while the anthropogenic sources include burning of fossil fuel (coal, natural gas, and oil), deforestation, and the cultivation of land that increases the decomposition of soil organic matter and crop and animal residues. Natural sources of CH4 emission include wetlands, termite activities, and oceans. Paddy fields used for rice production, livestock production systems (enteric emission from ruminants), landfills, and the production and use of fossil fuels are the main anthropogenic sources of CH4. Nitrous oxide, in addition to being a major GHG, is also an ozone-depleting gas. N2O is emitted by natural processes from oceans and terrestrial ecosystems. Anthropogenic N2O emissions occur mostly through agricultural and other land-use activities and are associated with the intensification of agricultural and other human activities such as increased use of synthetic fertiliser (119.4 million tonnes of N worldwide in 2019), inefficient use of irrigation water, deposition of animal excreta (urine and dung) from grazing animals, excessive and inefficient application of farm effluents and animal manure to croplands and pastures, and management practices that enhance soil organic N mineralisation and C decomposition. Agriculture could act as a source and a sink of GHGs. Besides direct sources, GHGs also come from various indirect sources, including upstream and downstream emissions in agricultural systems and ammonia (NH3) deposition from fertiliser and animal manure.

Soils harbour diverse soil faunaand a wide range of soil microorganisms. These fauna and microorganisms directly contribute to soil greenhouse gas (GHG) fluxes via their respiratory and metabolic activities and indirectly by changing the physical, chemical and biological properties of soils through bioturbation, fragmentation and redistribution of plant residues, defecation, soil aggregate formation, herbivory, and grazing on microorganisms and fungi. Based on recent results, the methods and results found in relation to fauna as well as from fungi and plants are presented. The approaches are outlined, and the significance of these hitherto ignored fluxes is discussed.

Agriculture is a significant source of GHGsglobally and ruminant livestock animals are one of the largest contributors to these emissions, responsible for an estimated 14% of GHGs (CH4and N2O combined) worldwide. A large portion of GHG fluxes from agricultural activities is related to CH4 emissions from ruminants. Both direct and indirect methods are available. Direct methods include enclosure techniques, artificial (e.g. SF6) or natural (e.g. CO2) tracer techniques, and micrometeorological methods using open-path lasers. Under the indirect methods, emission mechanisms are understood, where the CH4 emission potential is estimated based on the substrate characteristics and the digestibility (i.e. from volatile fatty acids). These approximate methods are useful if no direct measurement is possible. The different systems used to quantify these emission potentials are presented in this chapter. Also, CH4 from animal waste (slurry, urine, dung) is an important source: methods pertaining to measuring GHG potential from these sources are included.

Methods and techniques are described for automated measurements of greenhouse gases (GHGs) in both the laboratory and the field. Robotic systems are currently available to measure the entire range of gases evolved from soils including dinitrogen (N2). These systems usually work on an exchange of the atmospheric N2with helium (He) so that N2 fluxes can be determined. Laboratory systems are often used in microbiology to determine kinetic response reactions via the dynamics of all gaseous N species such as nitric oxide (NO), nitrous oxide (N2O), and N2. Latest He incubation techniques also take plants into account, in order to study the effect of plant–soil interactions on GHGsand N2 production. The advantage of automated in-field techniques is that GHG emission rates can be determined at a high temporal resolution. This allows, for instance, to determine diurnal response reactions (e.g. with temperature) and GHG dynamics over longer time periods.

Agricultural lands make up approximately 37% of the global land surface, and agriculture is a significant source of greenhouse gas (GHG) emissions, including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Those GHGs are responsible for the majority of the anthropogenic global warming effect. Agricultural GHG emissions are associated with agricultural soil management (e.g. tillage), use of both synthetic and organic fertilisers, livestock management, burning of fossil fuel for agricultural operations, and burning of agricultural residues and land use change. When natural ecosystems such as grasslands are converted to agricultural production, 20–40% of the soil organic carbon (SOC) is lost over time, following cultivation. We thus need to develop management practices that can maintain or even increase SOCstorage in and reduce GHG emissions from agricultural ecosystems. We need to design systematic approaches and agricultural strategies that can ensure sustainable food production under predicted climate change scenarios, approaches that are being called climate‐smart agriculture (CSA). Climate‐smart agricultural management practices, including conservation tillage, use of cover crops and biochar application to agricultural fields, and strategic application of synthetic and organic fertilisers have been considered a way to reduce GHG emission from agriculture. Agricultural management practices can be improved to decreasing disturbance to the soil by decreasing the frequency and extent of cultivation as a way to minimise soil C loss and/or to increase soil C storage. Fertiliser nitrogen (N) use efficiency can be improved to reduce fertilizer N application and N loss. Management measures can also be taken to minimise agricultural biomass burning. This chapter reviews the current literature on CSA practices that are available to reduce GHG emissions and increase soil Csequestration and develops a guideline on best management practices to reduce GHG emissions, increase C sequestration, and enhance crop productivity in agricultural production systems.

GHGemissions are usually the result of several simultaneous processes. Furthermore, some gases such as N2 are very difficult to quantify and require special techniques. Therefore, in this chapter, the focus is on stable isotopemethods. Both natural abundance techniques and enrichment techniques are used. Especially in the last decade, a number of methodological advances have been made. Thus, this chapter provides an overview and description of a number of current state-of-the-art techniques, especially techniques using the stable isotope15N. Basic principles and recent advances of the 15N gasflux method are presented to quantify N2 fluxes, but also the latest isotopologue and isotopomermethods to identify pathways for N2O production. The second part of the chapter is devoted to 15N tracing techniques, the theoretical background and recent methodological advances. A range of different methods is presented from analytical to numerical tools to identify and quantify pathway-specific N2O emissions. While this chapter is chiefly concerned with gaseous N emissions, a lot of the techniques can also be applied to other gases such as methane (CH4), as outlined in Sect. 5.3.

Several approaches exist for measuring greenhouse gases (GHGs), mainly CO2, N2O, and CH4, from soil surfaces. The principle methods that are used to measure GHG from agricultural sites are chamber-based techniques. Both open and closed chamber techniques are in use; however, the majority of field applications use closed chambers. The advantages and disadvantages of different chamber techniques and the principal steps of operation are described. An important part of determining the quality of the flux measurements is the storage and the transportation of the gas samples from the field to the laboratory where the analyses are carried out. Traditionally, analyses of GHGs are carried out via gas chromatographs (GCs). In recent years, optical analysers are becoming increasingly available; these are user-friendly machines and they provide a cost-effective alternative to GCs. Another technique which is still under development, but provides a potentially superior method, is Raman spectroscopy. Not only the GHGs, but also N2, can potentially be analysed if the precision of these techniques is increased in future development. An important part of this chapter deals with the analyses of the gas concentrations, the calculation of fluxes, and the required safety measures. Since non-upland agricultural lands (i.e. flooded paddy soils) are steadily increasing, a section is devoted to the specificities of GHG measurements in these ecosystems. Specialised techniques are also required for GHG measurements in aquatic systems (i.e. rivers), which are often affected by the transfer of nutrients from agricultural fields and therefore are an important indirect source of emission of GHGs. A simple, robust, and more precise methodof ammonia (NH3) emission measurement is also described.

Micrometeorological techniques are useful if greenhouse gas (GHG) emissions from larger areas (i.e. entire fields) should be integrated. The theory and the various techniques such as flux-gradient, aerodynamic, and Bowen ratio as well as Eddy correlation methods are described and discussed. Alternative methods also used are Eddy correlation, mass balance techniques, and tracer-based methods. The analytical techniques with current state-of-the-art approaches as well as the calculation procedures are presented.

Hlavnim cilem studie zaměřene na resersi odborne literatury, bylo zjistit, jake jsou v odborných publikacich u nas a v zahranici požadavky na specificke pohybove cinnosti ve vybraných sportovnich hrach (basketbal, futsal, hazena, tenis, volejbal, florbal), ktere se hraji ve sportovnich halach. Zaměřili jsme se na rychlost hraců a na pohybove cinnosti při utkanich a treninku. Dilcimi cili bylo zjistit, jake se poživaji rychlostni kategorie v různých sportovnich hrach a vygenerovat z nich ty nejvice využivane a jake specificke pohyby se sleduji v jednotlivých sportovnich hrach při analýzach utkani a treninků. Hlavni výzkumnou metodou byla analýza odborne literatury. Výsledkem studie je doporuceni rychlostnich kategorii a specifických pohybových cinnosti pro jednotlive sportovni hry, ktere budou soucasti analýz a vyhodnoceni z monitoringu pohybů hraců z cipů SEWIO při utkanich a treninku, ktere bude vyhodnocovat specialni software. Studie vznikla jako soucast výzkumneho projektu "Výzkum fuze dat z MEMS senzorů a nove sirokopasmove radiove technologie pro analýzu mikro-pohybů osob (Identifikacni kod projektu: FV10394)."

Deep sternal wound infection is a feared complication of cardiac surgery due to the negative impact on mortality, morbidity and long-term survival. Its incidence has remained more or less unchanged over the last three decades despite the significant increase in patients´ morbidity and complexity of cardiac surgery. The review summaries strategies to reduce the incidence of deep sternal wound reflecting general surgical site infection prevention and specificities of surgery performed through the median sternotomy. Furthermore, contemporary evidence-based recommendations for prevention of this complication are highlighted in the review. Key words: sternal infection - prevention - cardiac surgery.

PURPOSE OF THE STUDY Outcome analysis of penetrating cardiac and great vessels injury within the 15-year existence of the cardiac surgery service as a part of the major trauma centre of the University Hospital Olomouc MATERIAL AND METHODS Retrospective analysis of a group of a total of 16 patients who underwent a surgery for penetrating cardiac and great vessels injury since II/2002 to XI/2016. The dominant causes of penetrating trauma were stab injuries (15 patients, 94%), in one patient only (6%) it was a gunshot injury. The mean age of the patients included in the group was 42.9 ± 16.1 years, with men significantly prevailing (13 patients, 81%). A total of 7 injured persons (44%) were haemodynamically stable when admitted, 9 injured persons (56%) were unstable or in critical condition. The average transfer distance was 48.8 ± 34.5 km; the injured were admitted on average 115.9 ± 154.8 minutes after being injured. Preoperatively, all the injured suffered from pericardial effusion (5 mm) confirmed by TTE (81%) or CTA (19%). In 4 patients (25%) pericardial drainage for cardiac tamponade was performed before surgery. RESULTS All the penetrating cardiac and great vessels injuries were repaired by cardiac surgeon, in one case only (6%) the extracorporeal circulation support was used. The injury of coronary arteries was in one case managed by CABG and in the other case by ligation of the peripheral part of the coronary artery. In 4 patients (25%) also a penetrating injury of other organs was simultaneously managed. The mean ICU stay reached 85.8 ± 91.9 hours, on average 5.6 ± 9.3 units of red blood cells were administered during the in-hospital stay which lasted on average 7.1 ± 2.4 days. In the group a nonsignificant increase of left ventricular ejection fraction (44.1 ± 4.7 vs. 49.3 ± 3.2, p = 0.882) was reported at discharge of the injured patients. One patient died on the 78 th day of hypoxic brain damage (6% three-month mortality). The long-term survival analysis showed 94% one-year and 88% five-year cumulative survival in the group. DISCUSSION The incidence of the penetrating cardiac and great vessels injury is directly dependent on the crime level in the respective countries and regions. A cardiac arrest, severe hemodynamic instability, unconsciousness, serious concomitant injury, gunshot injury, multiple or atrial injury represent independent predictors of death in these injuries. The total three-month mortality in penetrating cardiac and great vessels injury ranges from 18 to 42%, the presence of vital signs at the time of hospital admission is associated with 78-92% probability of survival. The surviving patients show excellent long-term results with the exception of those who suffered a severe damage to valve apparatus or with significantly depressed left ventricular function. CONCLUSIONS Our experience proves a high survival rate of patients with penetrating cardiac and great vessels injury. The centralisation of the care into the major trauma centre with a cardiac surgery background, a unified treatment algorithm, and a vital interdisciplinary cooperation are the key goal of successful management of these injuries. Key words:penetrating injury, cardiac injury, great vessel injury, outcome. Práce byla podpořena programem institucionální podpor.

Acute massive pulmonary embolism remains potentially lethal with mortality varying between 2553%. In the thrombolytic era, surgical pulmonary embolectomy is deemed as a rescue approach for patients with absolute contraindication of thrombolysis or its failure. However, close interdisciplinary cooperation, meticulous choice of optimal reperfusion strategy, standardization of surgical approach, and mainly the inclusion of mechanical circulatory support into the treatment algorithm have led to a drop in in-hospital mortality below 10% in the last 10 years. Nevertheless, cardiac arrest and refractory cardiogenic shock still remain independent risk factors of death with mortality exceeding 70%. Extracorporeal membrane oxygen therapy provides rapid circulatory support, end-organ perfusion and oxygenation which are essential for right-sided obstruction haemodynamic. Subsequently, optimal reperfusion strategy can be chosen or patients may be transported for it. The review highlights the contemporary role of surgical pulmonary embolectomy and extracorporeal membrane oxygen therapy in the treatment algorithm for acute massive pulmonary embolism, summarising current perspectives on the indications and contraindications for these treatment strategies and their results.Key words: massive pulmonary embolism - surgical pulmonary embolectomy - extracorporeal membrane oxygen therapy.

Summary Results from the pioneering research on the interactions between pH and denitrification in soil from the 1950s to the present are reviewed, the changing perceptions of this complex relationship are discussed, and the current status of the subject is assessed. Facets of this relationship that are analysed in detail include the direct or indirect influence of pH on overall denitrification rates in soils, changes in the composition of gaseous products that depend on pH, methods for measuring the process, the concept of an optimum pH for denitrification, and the adaptation of microbial denitrifying communities to acidic environments. The main conclusions to be drawn are as follows. Total gaseous emissions to the atmosphere (N2O, NO and N2) have repeatedly been shown to be less in acidic than in neutral or slightly alkaline soils. This may be attributable to smaller amounts of organic carbon and mineral nitrogen available to the denitrifying population under acid conditions rather than a direct effect of low pH on denitrification enzymes. Numerous laboratory and field studies have demonstrated that the ratio N2O:N2 is increased when the pH of soils is reduced. The relation between soil pH and potential denitrification as determined by various incubation methods remains unclear, results being influenced both by original conditions in soil samples and by unknown changes during incubation. The concept of an optimum pH for denitrification has been frequently proposed, but such a term has little or no meaning without reference to specific attributes of the process.

Results of 23 years of observations of the Perseid meteor shower by the Ondřejov meteor radar in the period 1958–1996 are presented. Activity profiles in four categories of echo durations differ slightly in the position of the activity peak and other characteristics of the central core in the range of solar longitudes (Eq.1950.0) 138.0° ⩽ L ○· ⩽ 140.5°. Maximum activity of the central core is allocated at L ○· = 139.17°±0.06° in accordance with previous studies. The variation ratio of the year-to-year shower activity along the stream within the above L ○· limits was found to be 2.2 : 1.

Meteoric head echo statistics based on the Perseid observations carried out by the high-power meteor radar at the Springhill Meteor Observatory in the period 1957–1982 are dealt with. A total of 1945 head echoes was recorded during 271 h covering the central part of the Perseid activity in the interval of solar longitudes 139.5° ⩽ L⊙ ⩽ 140.10 (eq. J2000.0). The rate of their occurrence shows an irregular diurnal variation with a minimum near upper culmination of the shower radiant. The ratio of the head echo rate to overdense echo rate having durations T ⩾ 1 s varies from 2.1% at 17 h 30 m LT to about 5.0% at 22 h LT. Attention was paid also to the delay of a secondary echo appearing after the head echo. The maximum delay appears at 5 h 30 m LT and coincides with the lower culmination of the Perseid radiant when the mean delay represents some 2.5 s while its minimum value of 0.05 s coincides with the upper culmination at 17 h 30 m LT.

The occurrence of fragmenting particles was investigated from radar observations of the Perseids at Ondřejov Observatory. Diurnal patterns of fragmenting meteoroids are presented. Their minimum occurrence coincides with the culmination of the Perseid radiant while the maximum appears at the time of sunset at meteor heights. Solar longitude of the main contribution of fragmenting meteoroids at L⊙ = 138°86±0°04 (equinox 1950.0) fits with the peak activity of the new filament in the stream. This supports the concept of the low age of the filament. The maximum proportion of fragmenting particles occurred in 1991.

The activity profile of the new filament in the Perseid meteor stream and its 1986-1994 levels were analyzed from Ondřejov radar observations. The filament was first detected in 1986 at its minimum activity level. Its maximum flux was observed in 1993. A secondary maximum appeared in the period 1988-1989. The cross-section profile of the new cloud shows an activity peak at L⊙ = 138°.87±0°.04 (equinox 1950.0).

Crucial Cerebellar Glial Cells The role of glial cells and their interaction with neurons in normal behavior is unclear. To address this question, Saab et al. (p. 749 , published online 5 July) studied a special type of glial cell in the cerebellum. Conditional mutant mice were produced in which the two glutamate receptor subunits normally present in Bergmann glial cells were efficiently ablated in a temporally controlled manner. Glutamate signaling of the glial cells contributed to the structural and functional integrity of the cerebellar network. Bergmann glial cells also played a role in the “fine-tuning” of neuronal processing, which is crucial for the fast and precise control of complex motor behavior.

The insect hormone ecdysterone stimulated dinitrogen fixation, heterocyst formation, cell size and protein synthesis in suspension cultures of the cyanobacterium Nostoc 6720 within 48 h when added to the culture at concentrations between 10-9 and 10-7 м. In the presence of the hormone the volume of vegetative cells increased by 6-fold and that of heterocysts by nearly twice as compared to untreated controls. All the observed effects were inhibited by the calcium- calmodulin inhibitor, trifluoperazine. Cholesterol used as a null control had no significant effect.

Limiting currents and volume flow rates in the self pumping regime were measured on a model rotating electrolyzer with a variable geometry. The volume flow rate depends not only on the radius of the inlet orifice, outer disc radius, and angular velocity, but also on the interelectrode distance. Experimental mean current densities are compared with those calculated by the finite-element method, from an equation based on the theory of similarity of the diffusion layer, and from the theory of the rotating disc electrode with a ring.

A theoretical relationship for mass transfer in the laminar flow region of streaming in a rotating electrolyser was derived by the method of similarity of the diffusion layer for electrodes placed sufficiently far from the rotation axis. The obtained relationship was compared with the known equations valid for systems with axial symmetry. The mean current densities were found from the numerical solution of the convective diffusion equation by the finite-element method and were compared with experimental results.

The distribution of local current densities in a rotating electrolyser with axial electrolyte inlet in a laminar flow regime was studied by the autoradiographic method. With all systems studied, the local current density decreased monotonically from a maximum value at the inner to a minimum at the outer boundary of the electrode. Experimental results are compared with the numerical solution of the convective diffusion equation by the finite element method.

Nitrogenase activity, assayed by the acetylene reduction technique, was estimated on control soils and soils which contained several species of earthworms. The worms and casts were separately assayed for nitrogenase activity. The results indicated that nitrogenase activity was associated with gut content or body surface of worms and also their casts. Nitrogen fixation was also enhanced in soils enriched with enchytraeids in the presence of leaf litter.

Nitrogenase activity associated with earthworms, their faeces and activity in soil was measured by the acetylene reduction technique. A clear increase in nitrogenase activity was found in field-deposited casts of Aporrectodea caliginosa in comparison with surrounding soil, although potential nitrogenase activity was significantly higher in soil than in casts. Nitrogenase activity associated directly with earthworms (Lumbricus rubellus ) was detected, indicating the presence of active N2-fixing bacteria on the body surface and/or in the gut. Laboratory experiments showed that nitrogenase activity in the casts of L. rubellus was higher than in unmodified soil, and that nitrogenase activity in soil was significantly increased by the burrowing and feeding activity of these worms. This paper discusses the possible causes of these earthworm effects on soil nitrogenase activity and some methodological problems of determining the nitrogenase activity.

Meteor velocities can be determined from the diffraction characteristics of radar echoes from under-dense trails, but may be in error if atmospheric diffusion is neglected. Error factors are presented for circumstances when the diffusion coefficient is known. By a suitable selection of measurements beginning with the first minimum, the error in velocity may be held to about 1%.

The amplitudes of meteor echoes recorded on high-power radar equipment at Springhill Meteor Observatory have been measured for 57 samples of about 500 meteors each, obtained at various times of day on at least 1 day per month. The number of echoes as a function of echo amplitude is represented by a power law and the exponent in this relation calculated for each sample. Within the limits of error, no strong diurnal or seasonal variations in this exponent have been found. Similarly, there are no significant changes in the exponent when the data are divided into groups according to the height at which the echoes occurred and also according to the distance from the radar to meteor trail.Calibration of the equipment and the methods employed in obtaining and reducing the data are treated in detail. Theory relating the number distribution of echo amplitudes to the distribution of meteoroid masses is reviewed and assessed critically.A best value for the average mass index, s, of the sporadic meteor population in the range from 7th to 10th magnitude is s = 2.3 ± 0.1. The dispersion of individual sample values of s is about ± 0.3.

The amplitude of meteor echoes is recorded on a logarithmic scale by a high-power radar equipment (λ = 9·2 m, PT=3 MW, G = 5·6) at Springhill Meteor Observatory near Ottawa. The smallest amplitude measured corresponds to a pulse power of 10−12 W, which represents a minimum electron line density of about 7 × 1011 el/m or a radio magnitude of + 10.Distribution curves of number of echoes as a function of echo power have been obtained from some 50 samples of 500 meteors each, at various times of day on about 1 day per month. The slopes showed little variation throughout the year. The statistical error in the slope value for any one sample was small, ~ 2–3%. However, determination of the mass index s from these slopes involves several problems. On the basis of simplest theory we have obtained for the sporadic background, with no definite seasonal or diurnal variation.During shower periods, lower values of s were obtained. For the 1966 Leonids, s for the shower was determined by estimating the percentage of shower meteors in the total sample. A value s = 1·7 ± 0·1 was obtained as the mean of 6 samples. It is not known to what extent the height-ceiling effect influences the observation of this shower.