The Effect of Hive Volume on Efficiency and Strength Conservation and Restoration of Food Supplies During the Wintering in Langstroth Hives

The influence of volume of the hive on wintering, colony strength and food supply was observed during the three-year period. Standard LR hives were used for the experiment. Colonies were tested based on the number of hive bodies and the number of frames in the brood hive bodies. The colonies were divided into two groups based on the number of frames: group I had eight frames in the brood bodies, the second group included 10 frames in the brood bodies. Based on the number of hive bodies, colonies were also divided into two groups: colonies with a single hive body and colonies with two hive bodies. The inspections were carried out in the autumn in late August and early September, and in the spring in late March and early April. Colony strength was determined by the amount of brood and food supplies through the amount of honey and pollen. It was found that the number of frames in the brood bodies had almost no impact on the colony strength and the amount of food in the autumn and spring inspections. Percentage ratio in spring and autumn inspections was more favourable in ten-frame hives considering the amount of bees and pollen. The ratio for the amount of brood between the two inspections was higher in eight-frame hives. The colonies replenished bees more rapidly and foraged pollen more efficiently in ten-frame hives while the colonies in eight-frame hives replenished brood quicker. It was found that, during the three-year period, the hive volume had impact on strength and food supply of colonies. Colonies that have wintered in two hive bodies had favourable ratio of spring and autumn inspections for the amount of bees, brood and pollen, while the ratio for the amount of honey was more favourable in the colonies with a single hive body. The colonies with two hive bodies quicker restored strength and pollen supply, while the colonies with a single hive body consumed honey supply more rationally

Bone mineral health is sensitively related to environmental cadmium exposure- experimental and human data

Exposure to cadmium (Cd) is recognised as one of the risk factors for osteoporosis, although critical exposure levels and exact mechanisms are still unknown. Here, we first confirmed that in male Wistar rats challenged orally with 6 different levels of Cd (0.3–10 mg/kg b.w.), over 28 days, there was a direct dose relationship to bone Cd concentration. Moreover, bone mineral content was significantly diminished by ∼15% (p < 0.0001) plateauing already at the lowest exposure level. For the other essential bone elements zinc (Zn) loss was most marked. Having established the sensitive metrics (measures of Cd exposure), we then applied them to 20 randomly selected human femoral head bone samples from 16 independent subjects. Bone Cd concentration was inversely proportional to trabecular bone mineral density and mineral (calcium) content and Zn content of bone, but not the donor's age. Our findings, through direct bone analyses, support the emerging epidemiological view that bone health, adjudged by mineral density, is extremely sensitive to even background levels of environmental Cd. Importantly, however, our data also suggest that Cd may play an even greater role in compromised bone health than prior indirect estimates of exposure could reveal. Environmental Cd may be a substantially determining factor in osteoporosis and large cohort studies with direct bone analyses are now merited

Влияние дисперсности порошка, давления и температуры спекания на микроструктуру и физико-механические свойства керамики из карбида бора

Основной целью настоящей работы было получение высокоплотного сверхтвердого керамического материала на основе карбида бора спеканием под высоким давлением без использования активирующих добавок. Исследованы микроструктура, плотность и твердость по Виккерсу образцов, спеченных из порошков карбида бора различной дисперсности при давлении 4 ГПа в интервале температур 1200 – 2000 °С.Основною метою цієї роботи було отримання високоякісного надтвердого керамічного матеріалу на основі карбіду бору спіканням під високим тиском без використання активуючих добавок. Досліджені мікроструктура, щільність і твердість по Віккерсу зразків, спечених з порошків карбіду бору різної дисперсності при тиску 4 ГПа в інтервалі температур 1200–2000 °С.The main purpose of this work was to obtain a high-density superhard ceramic material based on boron carbide by sintering under high pressure without the use of activating additives. The microstructure, density and Vickers hardness of samples sintered from boron carbide powders of various dispersities at a pressure of 4 GPa in the temperature interval 1200–2000 °C were investigated

European Mixed Forests: definition and research perspectives

peer-reviewedAim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) briefly review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material and methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any developmental stage, sharing common resources (light, water, and/or soil nutrients). The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used for specific objectives. A variety of structures and patterns of mixtures can occur, and the interactions between the component species and their relative proportions may change over time. The research perspectives identified are (i) species interactions and responses to hazards, (ii) the concept of maximum density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields of research indicate that gradient studies, experimental design approaches, and model simulations are key topics providing new research opportunities.The networking in this study has been supported by COST Action FP1206 EuMIXFOR

Redox Parameters in Blood of Thyroid Cancer Patients After the Radioiodine Ablation

The radioactive iodine (I-131) ablation is a well-accepted treatment modality for differentiated thyroid cancer patients. Unfortunately, the radiation induces the oxidative stress and damages cells and tissues, simultaneously activating the mechanisms of antioxidative defense. Since the mechanisms of those processes are not completely known, we wanted to examine the changes in the most important reactive oxygen species and antioxidative components, as well as their correlation and significance for lipid peroxidation. Our results showed that the level of thiobarbituric acid reactive substances was increased during the first 30 days after the radiotherapy. Among antioxidant components, superoxide dismutase was increased in the 3rd and 30th day; catalase in 7th and reduced glutathione in 3rd and 7th day after the radiotherapy. As regards the prooxidants, the reduction of hydrogen peroxide (H2O2) was recorded in 7th and 30th day, and superoxide anion radical (O-2(center dot-)) was unchanged after the exposure to I-131. These results indicate that differentiated thyroid cancer patients are under constant oxidative stress despite the observed increase in antioxidative and reduction in prooxidative parameters. The understanding of these early processes is important since their progress determines the latter effects of I-131 therapy

Growth and yield of mixed versus pure stands of Scots pine (Pinus sylvestris L. ) and European beech (Fagus sylvatica L.) analysed along a productivity gradient through Europe

Mixing of complementary tree species may increase stand productivity, mitigate the effects of drought and other risks, and pave the way to forest production systems which may be more resource-use efficient and stable in the face of climate change. However, systematic empirical studies on mixing effects are still missing for many commercially important and widespread species combinations. Here we studied the growth of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) in mixed versus pure stands on 32 triplets located along a productivity gradient through Europe, reaching from Sweden to Bulgaria and from Spain to the Ukraine. Stand inventory and taking increment cores on the mainly 60-80 year-old trees and 0.02-1.55 ha sized, fully stocked plots provided insight how species mixing modifies the structure, dynamics and productivity compared with neighbouring pure stands. In mixture standing volume (+12 %), stand density (+20 %), basal area growth (+12 %), and stand volume growth (+8 %) were higher than the weighted mean of the neighbouring pure stands. Scots pine and European beech contributed rather equally to the overyielding and overdensity. In mixed stands mean diameter (+20 %) and height (+6 %) of Scots pine was ahead, while both diameter and height growth of European beech were behind (−8 %). The overyielding and overdensity were independent of the site index, the stand growth and yield, and climatic variables despite the wide variation in precipitation (520-1175 mm year−1), mean annual temperature (6-10.5 °C), and the drought index by de Martonne (28-61 mm °C−1) on the sites. Therefore, this species combination is potentially useful for increasing productivity across a wide range of site and climatic conditions. Given the significant overyielding of stand basal area growth but the absence of any relationship with site index and climatic variables, we hypothesize that the overyielding and overdensity results from several different types of interactions (light-, water-, and nutrient-related) that are all important in different circumstances. We discuss the relevance of the results for ecological theory and for the ongoing silvicultural transition from pure to mixed stands and their adaptation to climate change.The networking in this study has been sup-ported by COST Action FP1206 EuMIXFOR. All contributors thanktheir national funding institutions to establish, measure, and analysedata from the triplets. The first author also thanks the BayerischenStaatsforsten (BaySF) for supporting the establishment of the plots,the Bavarian State Ministry for Nutrition, Agriculture, and Forestryfor permanent support of the project W 07 ‘‘Long-term experimentalplots for forest growth and yield research’’ (# 7831-22209-2013) andthe German Science Foundation for providing the funds for the pro-jects PR 292/12-1 ‘‘Tree and stand-level growth reactions on droughtin mixed versus pure forests of Norway spruce and European beech’’.Thanks are also due to Ulrich Kern for the graphical artwork, and totwo anonymous reviewers for their constructive criticism

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

The role of intracellular trafficking of CdSe/ZnS QDs on their consequent toxicity profile

Nanoparticle interactions with cellular membranes and the kinetics of their transport and localization are important determinants of their functionality and their biological consequences. Understanding these phenomena is fundamental for the translation of such NPs from in vitro to in vivo systems for bioimaging and medical applications. Two CdSe/ZnS quantum dots (QD) with differing surface functionality (NH2 or COOH moieties) were used here for investigating the intracellular uptake and transport kinetics of these QDs.status: publishe