Search results for "WINTER"
showing 10 items of 175 documents
Aviācijas drošības pārbaudes kontrolpunkta darbības plānošanas optimizācija
2021
Darba mērķis ir piedāvāt labāku prognozēšanas metodi aviācijas drošības pārbaudes kontrolpunktam, kas ļautu veidot un plānot precīzākus kontrolpunkta pārbaudes līniju darba grafikus. Precīzāki darba grafiki ļautu samazināt rindā gaidīšanas laiku, un ļautu pasažieriem ātrāk iziet drošības pārbaudi, bet no uzņēmējdarbības puses netiktu atvērtas pārāk daudz drošības pārbaudes līnijas, tādējādi izmantojot personāla resursu jaudu pilnībā. Tika izmantotas trīs datu kopas – izpildīto reisu datu tabula, pasažieru skenētās iekāpšanas kartes, dati par gaisa kuģu tipiem un to kapacitāti. Darbā ir aprakstīta šo datu kopu detalizēta priekšapstrāde. Plaši pielietojot dažādus vaicājumus tika iegūti jauni …
Life in the ice lane: the winter ecology of stream salmonids
2007
Despite the common view that conditions in winter strongly influence survival and population size of fish, the ecology of salmonids has not been as extensively studied in winter as in other seasons. In this paper, we review the latest studies on salmonid winter survival, habitat use, movement and biotic interactions as they relate to the prevailing physical and habitat conditions in rivers and streams. The majority of research conducted on the winter ecology of salmonids has been carried out in small rivers and streams, where temperatures are above zero and where there is no ice. Investigations in large rivers, regulated and dredged rivers, and under conditions of different ice formations a…
Temporal variation in reproductive allocation in a shield bug Elasmostethus interstinctus
1996
We investigated changes in the reproductive output and the effect of female phenotype on reproductive parameters in a shield bug Elasmostethus interstinctus (L.) (Heteroptera: Acanthosomatidae) over the whole reproductive period. At the beginning and the middle of the reproductive period eggs were smaller than at the end of the period. Clutch mass and number of eggs per clutch decreased in laying sequence, first clutches being much larger than any of the later ones. Lifetime fecundity correlated positively with female size: large females produced more eggs and lived longer than small ones. Egg size did not vary with female size. Offspring survival until adulthood increased with egg weight. …
Energy use, diapause behaviour and northern range expansion potential in the invasive Colorado potato beetle
2011
Summary 1. As organisms expand their range towards northern latitudes they will encounter selective factors like harsh winter conditions. The ability to cope with and adapt to harsh winters may depend on the variability and evolutionary potential of relevant traits. 2. One adaptation in insects is winter diapause. It is characterized by changes in physiology, behaviour or in both. Physiological changes include lowered metabolic rate that enhances survival by saving limited energy reserves during overwintering. Active behavioural changes like burrowing into the soil allow individuals to escape harsh conditions. 3. We examined variation in overwintering body mass, resting metabolic rate (CO2 …
Energy metabolism and metabolic rate of the alder leaf beetle Agelastica alni (L.) (Coleoptera, Chrysomelidae) under aerobic and anaerobic conditions…
2003
In early fall, adult alder leaf beetles (Agelastica alni L.) retreat, for overwintering, to the top layer of the soil near their forage trees where the ground gets easily waterlogged so that the beetles will be submerged and cut off from atmospheric oxygen. Hence, unlike most other adult insects, alder leaf beetles encounter hypoxia/anoxia in their natural habitat and this may occur at moderate temperature. Exposing beetles to pure nitrogen gas at 20 degrees C had similar behavioral and metabolic effects as submerging them in water, causing rapid immobility and increasing the content of lactate about sevenfold to some 5mgr;molg(-1) body weight during 10h anoxia. Recovery from 10 h hypoxia/a…
Discovery of lunasin peptide in triticale (X Triticosecale Wittmack)
2012
Lunasin is a novel, cancer-preventive, anti-inflammatory and cholesterol-reducing peptide that was originally isolated from soy and later from barley, wheat and rye. We report the first discovery of lunasin in triticale (X Triticosecale Wittmack). Moreover, we report first data of lunasin content in winter rye and wheat genotypes grown in Northern Europe. These data are novel as previously published data on finding of lunasin in cereals were obtained in genotypes grown in Korea. Lunasin content was uncovered using a previously published procedure for isolation from cereals and identified by LC-MS/MS assay. We found that triticale was the most lunasin-rich cereal, with the tested genotypes d…
Basal ice formation in snow cover in Northern Finland between 1948 and 2016
2018
Abstract Basal ice formation in the terrestrial snow cover is a common phenomenon in northern circumpolar areas, one having significant impacts on ecosystems, vegetation, animals and human activities. There is limited knowledge on the spatial and temporal occurrence of basal ice formation because of the sparse observation network and challenges involved in detecting formation events. We present a unique dataset on the annual extent of ice formation events in northern Finland between 1948 and 2016 based on reindeer herders’ descriptions of the cold season in their management reports. In extreme years, basal ice can form over wide geographical extents. In approximately half of the herding dis…
Northward range expansion requires synchronization of both overwintering behaviour and physiology with photoperiod in the invasive Colorado potato be…
2014
Abstract. Photoperiodic phenological adaptations are prevalent in many organisms living in seasonal environments. As both photoperiod and growth season length change with latitude, species undergoing latitudinal range expansion often need to synchronize their life cycle with a changing photoperiod and growth season length. Since adaptive synchronization often involves a large number of time-consuming genetic changes, behavioural plasticity might be a faster way to adjust to novel conditions. We compared behavioural and physiological traits in overwintering (diapause) preparation in three latitudinally different European Colorado potato beetle (Leptinotarsa decemlineata) populations reared u…
Can Physiological and Psychological Factors Predict Dropout from Intense 10-Day Winter Military Survival Training?
2020
Background: In the military context, high levels of physiological and psychological stress together can compromise individual&rsquo
Ecotoxicological assessment of mineralized stratum water as an environmentally friendly substitute for agrochemicals
2022
Received: May 2nd, 2022 ; Accepted: July 17th, 2022 ; Published: July 28th, 2022 ; Correspondence: maryna.galytska@pdaa.edu.ua; akalinichenko@uni.opole.pl As a result of military operations on the territory of Ukraine, sown areas are reduced, the cost of plant protection products and fertilizers increases which emphasizes the problem of obtaining maximum yields from a smaller area of farmland. Given that a shortage of food grains can cause a global food crisis, research on the use of MSW as an environmentally friendly substitute for agrochemicals is relevant today. The aim of the research was to assess the ecotoxicological properties of MSW as an environmentally friendly substitute for synt…