Diabetes mellitus is a chronic metabolic disorder with a high prevalence worldwide. Animal models of diabetes represent an important tool in diabetes investigation that helps us to avoid unnecessary ...and ethically challenging studies in human subjects, as well as to obtain a comprehensive scientific viewpoint of this disease. Although there are several methods through which diabetes can be induced, chemical methods of alloxan- and streptozotocin-induced diabetes represent the most important and highly preferable experimental models for this pathological condition. Therefore, the aim of this article was to review the current knowledge related to quoted models of diabetes, including to this point available information about mechanism of action, particular time- and dose-dependent protocols, frequent problems, as well as major limitations linked to laboratory application of alloxan and sterptozotocin in inducing diabetes. Given that diabetes is known to be closely associated with serious health consequences it is of fundamental importance that current animal models for induction of diabetes should be continuously upgraded in order to improve overall prevention, diagnosis and treatment of this pathological condition.
Intangible Cultural Heritage (ICH) within the cultural tourism framework has opened up space for reconsideration of the ways in which living heritage, the tourist market, and target tourist groups ...are intertwined, and how their interaction affects the identity constructs of members of local communities. By including specific domains of living cultural practices in tourist offers, a kind of seesaw has emerged, with economic interests leading to the improved existence of practiced heritage on one side and the fact that ICH becomes a commodity primarily driven by the need of every tourist to literally experience heritage in the same way, becoming an exceedingly marketable commodity, on the other. The living tissue of tourism and ICH, in any case, represents one of the significant resources within which it is possible to realize UNESCO's guiding idea of heritage as a global point of encounter for different cultures. Both of these concepts are in constant processes of reconsidering what has been achieved and are attempting, through upcoming activities, to avoid dead ends and poorly implemented solutions.
Mapping based on open data sources in digital form represents a revolution in geoinformatics science and practice. Traditionally, the mapping approach required significant material resources and ...expertise to create accurate and up-to-date maps. With the development of geographic information systems (GIS) and an increasing number of websites that provide free access to a huge volume of geospatial information, this way of mapping is becoming more and more present. Open data sources, often free or at low cost, support the download or use of global geospatial data. This enabled the spread of geographical knowledge and skills at a much higher level, including individuals, organizations and social communities. Open data sources provide new mapping opportunities, enabling better understanding and solving complex problems in different fields. The paper systematizes knowledge and techniques from this area and, on the example of the Military Geographical Institute, shows the need for both the use and sharing of such data.
The primary function of introducing the so-called ?camouflage suit? or camo suit into the military and police formations in the late 1980s also had the consequence of transferring its functions to a ...secondary level, by the sheer proliferation ofsuch sets used in war activities during the breakup of the former Yugoslavia. For the ethnographic heritage, the challenge of the liminal status of the camouflage suit within the framework of men?s work pattern in the redefined folk economy is reflected in the short period of its establishment and use. On the other hand, its widespread use and an ongoing cultural phenomenon support the musealization of samples of such a clothing pattern, as well as the need to set up research on the impact of folk economy on clothing culture and vice versa. As camouflage suits were obtained and used in the process of integration into the everyday work pattern of members of rural communities, retired men and ?weekend farmers? engaged in agricultural activities, they became a mirror image of the dissolution of late socialism as a social system in Serbia. This new status has contributed to the redefinition of the function and content of new men?s clothing patterns, in line with the broader changes in the value system and redistribution of state and social authority. Consequently, anthropologization of museological discourse creates suitable conditions for discussing the existence of the tertiary communicative role and significance of all types of military apparel, including camouflage suits.
An effective post-injury training program is essential to regain performance and fulfill criteria for return to sport for team sport athletes following anterior cruciate ligament (ACL) ...reconstruction. The aim of this study was to compare the effects of 6 weeks of eccentric-oriented strength training vs. traditional strength training during the late-stage ACL-rehab phase on leg strength and vertical and horizontal jumping performance in professional team sport athletes.
Twenty-two subjects (14 males, 8 females, age 19.9 ± 4.4 years, mass 77.4 ± 15.6 kg, height 182.4 ± 11.7 cm) (mean ± SD) with a unilateral reconstructed ACL (BTB graft) were included in the study. All participants enrolled in the same rehabilitation protocol prior to the training study. Players were randomly assigned to an experimental (ECC: n = 11, age 21.8 ± 4.6 years, mass 82.7 ± 16.6 kg, height 185.4 ± 12.2 cm), and a control group (CON: n = 11, age 19.1 ± 2.1 years, mass 76.6 ± 16.5 kg, height 182.5 ± 10.2 cm). Both groups underwent an equivolumed rehabilitation program, with the only difference being in strength training, which consisted of flywheel training vs. traditional strength training for the experimental and control groups, respectively. Testing was organized before and after the 6-week training programs and included isometric semi-squat tests (ISOSI-injured and ISOSU-uninjured legs), vertical jump tests (CMJ), single-leg vertical jump tests (SLJI-injured and SLJU-uninjured legs), single-leg hop tests (SLHI-injured and SLHU-uninjured legs), and triple hop tests (TLHI-injured and TLHU-uninjured legs). In addition, limb symmetry indexes were calculated for the isometric semi-squat (ISOSLSI) test, the single-leg vertical jump (SLJLSI), and the hop (SLHLSI) tests, as well as the triple-leg hop (THLLSI) test.
Main effects of time across training were observed for all dependent variables (posttest > pretest,
< 0.05). Significant group-by-time interactions were found for ISOSU (
< 0.05, ES = 2.51, very large), ISOSI (
< 0.05, ES = 1.78, large), CMJ (
< 0.05, ES = 2.23, very large), SLJI (
< 0.05, ES = 1.48, large), SLHI (
< 0.05, ES = 1.83, large), and TLHI (
< 0.05, ES = 1.83, large).
This study suggests that eccentric-oriented strength training in late-stage ACL recovery, undertaken twice or three times weekly for 6 weeks, results in better outcomes than traditional strength training in leg strength, vertical jump ability, and single and triple hop tests with injured legs in professional team sport athletes. It seems that flywheel strength training can be recommended in late-stage ACL recovery for professional team sport athletes in order to regain recommended performance outcome levels faster.
Coppicing consists of periodically cutting back tree stems to ground level to stimulate the growth of multiple stems from the stool. In Central Europe, many coppiced forests were abandoned at the ...beginning of the last century owing to a decline in the demand for charcoal and wood. This was assumed to enable the forests to recover and the properties to become similar to those of unmanaged forest (high forest). Most studies on abandoned coppiced forest have focused on forest recovery, while soil recovery has generally been overlooked. With the aim of filling this gap, this study investigated the effect of coppicing abandonment on soil recovery by analysing the changes in soil enzyme activities (dehydrogenase, β-glucosidase, invertase, urease, acid phosphatase and arylsulphatase). Two differently managed sessile oak (Quercus petraea) forests were selected for study: a former coppice forest, abandoned >90 years ago, and an undisturbed forest. The analytical data were compared to assess the degree of recovery of the soil in the abandoned coppice forest. The soil organic matter content was two times lower in the abandoned coppice than in the high forest, suggesting that organic matter depletion due the past coppicing is a long-term effect. All of the absolute enzyme activities were also two times lower in the abandoned coppice forest soil than in the high forest soil. However, the specific enzyme activities were similar in both types of soil. This indicates that metabolic activity is similar in both soil types, suggesting that it either recovers faster than organic matter and soil enzyme activity or that, despite the depletion in organic matter and enzyme activities, metabolic activity was sustained in coppiced forest soil. However, in the latter case this would imply that organic matter and soil enzymes were lost in exactly the same proportion, which is highly improbable.
Display omitted
•A century after coppice abandonment soil organic matter content is still very low.•Soil enzyme activities are half in abandoned coppice than in high forest.•Soil specific enzyme activities in abandoned coppice forest are similar to that of high forest•Recovery of soil functionality after coppice abandonment seems a very slow process.•Caution is recommended before promoting re-introduction of coppicing in Central Europe.
Analysis of floodplain forest sensitivity to drought Kowalska, Natalia; Šigut, Ladislav; Stojanović, Marko ...
Philosophical transactions of the Royal Society of London. Series B. Biological sciences,
10/2020, Letnik:
375, Številka:
1810
Journal Article
Recenzirano
Odprti dostop
Floodplain forests are very complex, productive ecosystems, capable of storing huge amounts of soil carbon. With the increasing occurrence of extreme events, they are today among the most threatened ...ecosystems. Our study's main goal was to assess the productivity of a floodplain forest located at Lanžhot in the Czech Republic from two perspectives: carbon uptake (using an eddy covariance method) and stem radius variations (using dendrometers). We aimed to determine which conditions allow for high ecosystem production and what role drought plays in reducing such production potential. Additionally, we were interested to determine the relative soil water content threshold indicating the onset and duration of this event. We hypothesized that summer drought in 2018 had the most significant negative effects on the overall annual carbon and water budgets. In contrast with our original hypothesis, we found that an exceptionally warm spring in 2018 caused a positive gross primary production (GPP) and evapotranspiration (ET) anomaly that consequently led in 2018 to the highest seasonal total GPP and ET from all of the investigated years (2015-2018). The results showed ring-porous species to be the most drought resistant. Relative soil water content threshold of approximately 0.45 was determined as indicating the onset of drought stress. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.
•Ultra high performance concrete (UHPC) for multipurpose.•Porosity decrease with increasing nano-silica (nS) content.•Strength increased with addition of 2% nS in UHPC with up to 50% barite ...sand.•Resistance to radiation was improved with the addition of barite aggregate.
The development of building materials with improved characteristics and their application for increasing structure durability and sustainability is one of the goals in construction sector. The main objective of this paper is to evaluate the influence of nano-silica replacement of cement (2% or 5%) and aggregate type (quartz, barite or its combination 50:50 by volume) on the properties of ultra high performance concrete (UHPC). UHPC with nano-silica and combination of barite and quartz aggregate is composite which has finer pore-size distribution, improvement in compressive and flexural strength and in radiation protection characteristics, with potential usage as building material for hospitals and nuclear facilities.
•Sap flow and stem radial variations were evaluated in mixed floodplain forests.•Stem radial variations and sap flow was reflected in species’ sensitivity to drought.•Tree water deficit was coupled ...to drying soil and sap flow to evaporation demand.•Narrow-leaved ash showed the most conservative water use but the highest stem growth.•Groundwater decline and frequent droughts may alter tree species composition.
Recent changes in the floodplain forests of Central Europe, caused mainly by changes in hydrological management and the increased frequency of droughts due to climate change, have led to severe degradation of floodplain ecosystems. Our main objective was to determine the sensitivity of trees to drought by observing the response of the tree phenology, stem radial growth, and physiology (sap flow) of three predominant tree species, namely English oak, narrow-leaved ash, and common hornbeam, to the environmental variables (climate). Stem radial growth began before bud break in ring-porous oak and ash, whereas in diffuse-porous hornbeam, growth onset occurred after leaf formation. The early onset with intense growth during favorable months (April–May) observed in ring-porous species was a major prerequisite for the successful growth of oak and ash at this site. Tree water deficit (TWD), an indicator of stem hydration, was triggered by decreasing soil moisture in all species, and was most prominent in ash, followed by oak. Intriguingly, sap flow was decoupled from TWD in all species and was driven primarily by evaporative demand from the atmosphere. Oak was the least conservative in regulating sap flow under atmospheric drought followed by hornbeam, whereas ash was most restricted and reduced its transpiration during dry periods. In contrast, ash was characterized by the highest radial growth and growth-based water-use efficiency. The lower water storage capacity of oak and ash is likely compensated by deep rooting and drought avoidance strategies, respectively. Tree species that tend to use surface soil water could be severely limited by more extractive species such as hornbeam. Despite the contrasting leaf and wood phenology, stomatal control, and rooting depth among the studied floodplain tree species, they exhibited analogous sap flow and water storage dynamics responses to drier conditions that enabled them to co-exist in the South Moravian Region. Nevertheless, our results suggest that the severe droughts and human-induced alterations in groundwater pose serious threats to floodplain forests in Central Europe, with certain tree species being unable to adapt to these altered conditions.
Under ongoing climate change, more frequent and severe drought periods accompanied by heat waves are expected in the future. Under these conditions, the tree's survival is conditioned by fast ...recovery of functions after drought release. Therefore, in the presented study, we evaluated the effect of long-term water reduction in soil on tree water use and growth dynamics of Norway spruce.
The experiment was conducted in two young Norway spruce plots located on suboptimal sites at a low altitude of 440 m a.s.l. In the first plot (PE), 25% of precipitation throughfall was excluded since 2007, and the second one represented the control treatment with ambient conditions (PC). Tree sap flow, stem radial increment, and tree water deficit were monitored in two consecutive growing seasons: 2015-2016, with contrasting hydro-climatic conditions.
Trees in both treatments showed relatively isohydric behavior reflected in a strong reduction of sap flow under the exceptional drought of 2015. Nevertheless, trees from PE treatment reduced sap flow faster than PC under decreasing soil water potential, exhibiting faster stomatal response. This led to a significantly lower sap flow of PE, compared to PC in 2015. The maximal sap flow rates were also lower for PE treatment, compared to PC. Both treatments experienced minimal radial growth during the 2015 drought and subsequent recovery of radial growth under the more the humid year of 2016. However, treatments did not differ significantly in stem radial increments within respective years.
Precipitation exclusion treatment, therefore, led to water loss adjustment, but did not affect growth response to intense drought and growth recovery in the year after drought.
PDF
