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Plant pathogenic nematodes play an important role in crop production and are difficult to control. One of them is Heterodera schachtii—a cyst nematode, pathogenic to sugar beet. Nature suggests a natural way to resolve this problem by using nematode-trapping fungi, one of which is Pleurotus ostreatus. It is one of the most widespread mushrooms in the world. It is a valuable and widely cultivated edible mushroom with nematocidal properties. The mycelium of this mushroom produces toxin droplets that paralyze nematodes, after which the nematodes become infected with the hyphae filament, resulting in their death. This feature can be put to practical use as a natural nematocidal agent. In this paper, we have described studies on the variability of the nematocidal properties in the progeny of three wild strains of P. ostreatus (Po1, Po2, Po4), obtained by crossing dikaryons with monokaryons (Buller phenomenon). The toxicity of mycelium was tested against the model organism Caenorhabditis elegans and against sugar beet pest—H. schachtii. The results of the study allowed the selection of the progeny heterokaryotic mycelia with the best parameters useful for in vitro control of both nematodes. They differed in the activity against C. elegans and H. schachtii, and in the toxic knobs production. The results indicated that the progeny of the Po1 strain presented a good ability to produce hyphal knobs in the presence of C. elegans, and progenies of the Po4 strain presented good quality of growth in preferred temperatures (10–25 °C). Three strains Po1 5dix27, Po2 20dix21, and Po4 2dix1, as well as a maternal strain Po4 controlled H. schachtii by entwining cysts better than other strains. These strains were moderately effective against C. elegans. Strains Po2 15dix17, Po4 1dix18, and Po4 1dix30 may be considered good controlling isolates against both tested organisms. The results of the research also clearly suggest that the killing properties of P. ostreatus mycelia should not be assessed only by their ability to produce toxic hyphal knobs. Their nematocidal properties also depend on other mechanisms developed by mycelia, which is observed as the lethality of nematodes. The results of this research will lead to a natural way to protect plants against nematodes. The research also proved the nematocidal properties of the wild strains to reduce the H. schachtii population in the soil.

In Poland the phase in which precipitation occurs impacts the availability of water in its reservoirs, the potential for hydrological droughts, snowfall flooding and winter recreation. The influence of warming on the occurrence of precipitation phases on the Polish scale has not been studied so far. Based on data from 42 synoptic stations for the period 1966–2020, this study discusses trends in the indices of liquid (Lq), mixed (Mx) and solid (Sd) precipitation describing their totals (T), frequencies (Nd) and contribution to overall precipitation totals (T%) and a number of days with overall precipitation (Nd%) from a seasonal perspective. Moreover, the influence of seasonal and daily air temperatures on long-term variability in the precipitation phase indices was assessed. The precipitation phase was discriminated based on the observations of weather phenomena noted as current and past weather considering days with precipitation ≥ 0.1 mm. Precipitation phases significantly reacted to current warming. The strongest and widespread were increasing trends in rains (+1.74 for LqNd, +5.35 mm for LqT, +3.51% for LqNd%, +4.08% for LqT% per decade) and decreasing trends in snowfalls (−1.92 for SdNd, −3.12 mm for SdT, −3.65% for SdNd%, −3.26% for SdT% per decade) in winter when the warming was weakest but average temperature was close to freezing point. In winter, air temperature explained 60%–80% of the variance in the frequency of snowfall and rainfall. Daily air temperature > –2 °C contributed to trends in winter rainfall while daily air temperature > 1 °C most contributed to trends in winter snowfall. No trends in winter mixed precipitation were due to opposite changes in its frequency above and below 1 °C. In spring, the increase in a liquid phase was due more to the melting of a solid and mixed phase, while in autumn, it was due more to the transformation of a mixed phase into a liquid phase. In spring, air temperature explained at most 30%–50% of the variance in the indices of snowfall frequency. Negative trends in mixed precipitation were significant in transitional seasons, being more prominent in spring than in autumn and were mostly driven by changes in daily air temperatures between 0 and 5 °C. A diminished percentage of summer rains on days with air temperatures below 15 °C was compensated by their increase above that threshold thus producing no long-term trends. Warming significantly weakened the relationships between precipitation phases and average seasonal air temperatures except for summer rainfalls.

Tubercle disease or a bacterial pocket disease of sugar beets are names used to describe one of the gall-malformed diseases of sugar beet roots. Xanthomonas beticola is the historical name of the pathogen supposedly causing bacterial pocket disease. There were no isolates deposited in any collection corresponding to the originally isolated bacteria, except two strains from the NCPPB (National Collection of Plant Pathogenic Bacteria, UK). However, both isolates were identified as related to Bacillus pumilus, which raised doubts about their pathogenicity. In our laboratory, greenhouse, and preliminary field experiments, we demonstrated that such strains are not pathogenic to sugar beets. Furthermore, both strains promoted their growth, improved their yield quality, and partly protected them against Rhizoctonia solani in a field experiment.

The objective of the study was to determine multi-annual changes and variability of occurrence of cold spells in summer and warm spells in winter on Spitsbergen in the period 1976–2016, and circulation conditions of their occurrence. Cold days in summer were defined as days with mean daily air temperature lower than temperature corresponding to the 10th percentile from daily temperature, and warm days in winter as days with mean daily air temperature exceeding the 90th percentile from daily air temperature. The research showed a statistically significant increase in mean air temperature, the rate of which in winter was more than four times higher than in summer. The observed warming translated into a decrease in the number of cold days in summer (-2.5 days/10 years in Svalbard Lufthavn and -1.3 days/10 years in Ny-Ålesund) and an increase in the number of warm days in winter (2.7 days/10 years in Svalbard Lufthavn and 2.4 days/10 years in Ny-Ålesund), and warm and cold spells related to the frequency of such days. The rate of the changes was higher in Svalbard Lufthavn than in Ny-Ålesund. The occurrence of cold days and cold spells was particularly related to the advection of air masses from the north-western sector. The occurrence of warm days and warm spells was related to the advection of air masses from the south-west.

Abstract Background Prenatal antibody transfer is an immune-mediated maternal effect by which females can shape postnatal offspring resistance to pathogens and parasites. Maternal antibodies passed on to offspring provide primary protection to neonates against diverse pathogenic antigens, but they may also affect offspring growth and influence the development of an offspring’s own immune response. The effects of maternal antibodies on offspring performance commonly require that the disease environment experienced by a mother prior to breeding matches the environment encountered by her offspring after hatching/birth. However, other circumstances, like postnatal rearing conditions that affect offspring food availability, may also determine the effects of maternal antibodies on offspring growth and immunity. To date, knowledge about how prenatal immune-mediated maternal effects interact with various postnatal rearing conditions to affect offspring development and phenotype in wild bird population remains elusive. Here we experimentally studied the interactive effects of pre-laying maternal immunization with a bacterial antigen (lipopolysaccharide) and post-hatching rearing conditions, altered by brood size manipulation, on offspring growth and humoral immunity of wild great tits (Parus major). Results We found that maternal immunization and brood size manipulation interactively affected the growth and specific humoral immune response of avian offspring. Among nestlings reared in enlarged broods, only those that originated from immunized mothers grew better and were heavier at fledging stage compared to those that originated from non-immunized mothers. In contrast, no such effects were observed among nestlings reared in non-manipulated (control) broods. Moreover, offspring of immunized females had a stronger humoral immune response to lipopolysaccharide during postnatal development than offspring of non-immunized females, but only when the nestling was reared in control broods. Conclusions This study demonstrates that offspring development and their ability to cope with pathogens after hatching are driven by mutual influences of pathogen-induced prenatal maternal effects and post-hatching rearing conditions. Our findings suggest that immune-mediated maternal effects may have context-dependent influences on offspring growth and immune function, related to the postnatal environmental conditions experienced by the progeny.

Severe symptoms of root rot on sugar beet have been observed in Poland and Germany since 2001. The symptom classification suggested girth scab as it was mistakenly classified on the basis of current classification, e.g. in LIZ. However, the cause of the disease was Aphanomyces cochlioides infection, not Streptomyces spp. According to these findings we cannot call the symptoms caused by A. cochlioides as 'girth scab'. The typical scab (girth scab) symptoms can be promoted by A. cochlioides infections. In many cases, A. cochlioides developed at the beginning of the season, during the seedling stage. Its further development was due to rainfall and was not routinely recognised in disease-changed tissues if in the middle of the summer the rainfall level was reduced. According to the described findings, renewed description and differentiation of the girth scab symptoms caused by Streptomyces spp. and root rot caused by A. cochlioides on sugar beet roots are suggested. Typical symptoms of the disease caused by A. cochlioides occur mainly on the upper part of the root but can also occur on its lower part, if weather conditions are favourable for the pathogen. The coexistence of A. cochlioides and Pythium spp. in the same niches is also possible. Currently the illustrations showing these symptoms are included in the 'girth scab' descriptions.

Two systems of Earth-centered inertial Newtonian orbital equations for a spherical Earth and three systems of post-Newtonian nonlinear equations, derived from the second post-Newtonian approximation to the Earth Schwarzschild field, are used to carry out a performance analysis of a numerical procedure based on the Dormand-Prince method for initial value problems in ordinary differential equations. This procedure provides preliminary post-Newtonian corrections to the Newtonian trajectories of middle-size space objects with respect to space-based acquisition, pointing, and tracking laser systems, and it turns out to be highly efficient. In fact, we can show that running the standard adaptive ode45 MATLAB routine with the absolute and relative tolerance, TOLa = 10−16 and TOLr = 10−13, respectively, provides corrections that are final within the eclipses caused by the Earth and close to final during the noneclipse phases. These corrections should be taken into account to increase the pointing accuracy in implementing the space-to-space laser links required for ablation of designated objects or communications between space terminals.

In this paper, we introduce a computational procedure that enables autonomous LEO laser trackers endowed with INSs to increase the current accuracy when shooting at middle distant medium-size LEO debris targets. The code is designed for the trackers to throw the targets into the atmosphere by means of ablations. In case that the targets are eclipsed to the trackers by the Earth, the motions of the trackers and targets are modeled by equations that contain post-Newtonian terms accounting for the curvature of space. Otherwise, when the approaching targets become visible for the trackers, we additionally use more accurate equations, which allow to account for the local bending of the laser beams aimed at the targets. We observe that under certain circumstances the correct shooting configurations that allow to safely and efficiently shoot down the targets, differ from the current estimations by distances that may be larger than the size of many targets. In short, this procedure enables to estimate the optimal shooting instants for any middle distant medium-size LEO debris target.

Phylogenetic analyses based on mitochondrial 16S rDNA, nuclear 28S rDNA, and morphological and ecological traits of Aulactinia, Urticina and Cribrinopsis sea anemones inhabiting the Arctic-boreal region indicate discordances between trees derived from molecular sequences and those based on morphological traits. Nuclear genes were more informative than mitochondrial and morphological datasets. Our findings indicate that 16S rDNA has limited applicability for phylogenetic analyses at lower taxonomic levels and can only be used for distinction of families. Although 28S rDNA allowed for the classification of distinct genera, it could not confirm that species of Urticina and Cribrinopsis, which appeared to be closely related, were correctly separated into two different genera. The nuclear tree revealed inconsistencies between specimens belonging to European Urticina crassicornis and Pacific U. crassicornis; the latter seems to be a different species. In contrast to Pacific U. crassicornis, the specimens collected from different localities in the Barents Sea are on the same tree branch. The same was observed for specimens of Aulactinia stella. Both species brood their young internally. The dispersal of sea anemones with brooding juveniles seems to be less limited than expected and might be sufficient to settle habitats more than a thousand kilometers away.

Ekologia względnie beztlenowych, mezofilnych, przetrwalnikujących bakterii celulolitycznych (WBMPBC) jest mało poznana. W literaturze przedmiotu znajdują się tylko nieliczne informacje dotyczące wpływu nawożenia oraz rodzaju uprawianej rośliny na występowanie w glebie WBMPBC. Dlatego celem naszych badań było wykazanie wpływu dodatku do gleby kompostów na bazie miału węgla brunatnego na właściwości chemiczne i liczebność względnie beztlenowych, mezofilnych, przetrwalnikujących bakterii celulolitycznych (WBMPBC) w glebie ryzosferowej i pozaryzosferowej wybranych roślin. Gleba pobrana z obiektów doświadczalnych była słabo kwaśna (pH – 6,2-6,4) i nieznacznie się różniła się zawartością makroelementów. Liczebność badanej grupy drobnoustrojów w glebie zależała od rodzaju kompostu i wynosiła od 9,42 do 3186,9 jtk (jednostki tworzące kolonie) w gramie suchej masy gleby (s. m. gleby). Wszystkie komposty stymulowały liczebność bakterii celulolitycznych w glebie pozarysoferowej. W przypadku ryzosfery kompost zawierający efektywne mikroorganizmy (EM) redukował liczebność WBMPBC. Największą liczebność badanej grupy drobnoustrojów stwierdzono w ryzosferze spod uprawy wiśni, nawożonej kompostem przygotowanym z węgla brunatnego z odpadem po produkcji owocników Pleuretus ostreatus (3186,9 jtk w g. s. m. gleby).

gleby ryzosferowej jabłoni, wiśni i truskawki nawożonej kompostami przygotowanymi na bazie miału z węgla brunatnego z dodatkiem grzybni Basidiomycota, wyizolowano sześć szczepów bakterii względnie beztlenowych, przetrwalnikujących zdolnych do rozkładu celulozy. Na podstawie morfologii, cech biochemicznych i sekwencji 16S rRNA izolaty sklasyfikowano do gatunków z rodzaju Paenibacillus. W pożywkach wybiórczych z dodatkiem bibuły filtracyjnej (FP) i karboksymetylocelulozy (CMC) badane izolaty syntetyzowały enzymy, które hydrolizują celulozę amorficzną i krystaliczną. Badane izolaty w 14 i 28-dniowych hodowlach w pożywce z karboksymetylocelulzą (CMC) produkowały odpowiednio od 0 mU do 10,87 mU oraz od 10,73 do 21,13 mU CMCazy (karboksymetylocelulazy). Najwyższą aktywność enzymów scukrzających celulozę (FPazy) w pożywce z CMC wykazano w 14-dniowych hodowlach P. lautus EG_11 – 75,6 mU, Paenibacillus sp. EG_17 – 57,6 mU oraz P. woosongensis EG_15 – 38,9 mU. W pożywce z dodatkiem bibuły filtracyjnej (FP), najwyższą produkcję CMCazy i FPazy odnotowano w hodowlach P. lautus EG_11 – odpowiednio 79,85 i 118,83 mU.

The aim of this study was to estimate the susceptibility of Staphylococcus hominis bacteria to the bacteriostatic agent in respiratory pro­tective filters. Four types of filter media of different characteristics were tested. The number of bacteria was estimated by a culture-based method. It was proved that in treated filters the number of S. hominis was significantly reduced, even below the detection limit, while in untreated material bacteria were able to grow and multiply up to 100-fold within 8 hours. There was no correlation between filter structure and changes in the number of bacterial cells.

Rapid Arctic warming results in increased winter rain frequencies, which may impact glacial systems. In this paper, we discuss climatology and precipitation form trends, followed by examining the influence of winter rainfall (Oct⁻May) on both the mass balance and dynamics of Hansbreen (Svalbard). We used data from the Hornsund meteorological station (01003 WMO), in addition to the original meteorological and glaciological data from three measurement points on Hansbreen. Precipitation phases were identified based on records of weather phenomena and used—along with information on lapse rate—to estimate the occurrence and altitudinal extent of winter rainfall over the glacier. We found an increase in the frequency of winter rain in Hornsund, and that these events impact both glacier mass balance and glacier dynamics. However, the latter varied depending on the degree of snow cover and drainage systems development. In early winter, given the initial, thin snow cover and an inefficient drainage system, rainfall increased glacier velocity. Full-season winter rainfall on well-developed snow was effectively stored in the glacier, contributing on average to 9% of the winter accumulation.

This study reports on a case study about multimodal work in a primary physics classroom focusing on forces. Previous research reports that students benefit from multimodal work in science classrooms. Yet, few systematic studies have been performed to reveal how students represent their experiences and ideas of science phenomena over time within and across different semiotic modes (e.g., through action, speech, writing, and image, including multimodal ensembles). The design of the lessons was built around a number of experimental activities, starting with a puzzling phenomenon and where students for each experiment predicted, observed, described, and tried to come up with explanations. Based on social-semiotics, we combined analysis at an overall level (long timescale and large grain size) and a detailed level (short timescale and small grain size) to shed light on how the science content was represented within and between modes over the teaching and learning period, and what content was expressed in these representations. Our findings reveal how students moved from focusing on attributes such as a "heavy" regarding artifacts used in the experiments, towards the central physics processes, such as one object exerting force on another object. Furthermore, we were able to detect that such "signs of learning" were shown in students' small-group discussions and multimodal texts following a carefully orchestrated multimodal exposition by the teacher. Hence, such a careful multimodal orchestration appeared to be critical for the students' meaning-making about the science content.

Butterflies of the genus Phengaris have a highly specialised life cycle involving an obligatory relationship with Myrmica ants. A knowledge of the host ant specificity is essential for understanding the relationship between a particular Phengaris species and its hosts and also important for the conservation of these butterflies. Data on host ant specificity were collected in Poland, the Czech Republic, Slovakia and Ukraine. Five different Myrmica species were used by P. teleius as hosts (M. scabrinodis, M. rubra, M. ruginodis, M. rugulosa and M. gallienii) and at most localities it was not possible to distinguish a primary host - i.e. several Myrmica species were parasitized to similar extents. Three populations of P. nausithous were found in Poland and Ukraine. In every case, M. rubra was its primary host, although in the Kraków region (Poland) two nests of M. scabrinodis and two of M. ruginodis were infested by this butterfly species. P. alcon in the four populations investigated in Poland and Ukraine invariably only used M. scabrinodis as a host despite the presence of other Myrmica species. These results obtained suggest lack of host specificity in P. teleius and high host specificity in P. nausithous, which mainly uses M. rubra as its host across Europe. Moreover, the three populations of P. alcon investigated seem to be highly specific and use M. scabrinodis as a host, which confirms the high local specialisation of these populations.

In this paper, we investigate the singular Sturm-Liouville problem u′′=λg(u), u′(0)=0, βu′(1)+αu(1)=A, where λ is a nonnegative parameter, β≥0, α>0, and A>0. We discuss the existence of multiple positive solutions and show that for certain values of λ, there also exist solutions that vanish on a subinterval [0,ρ]⊂[0,1), the so-called dead core solutions. The theoretical findings are illustrated by computational experiments for g(u)=1/u and for some model problems from the class of singular differential equations (ϕ(u′))′+f(t,u′)=λg(t,u,u′) discussed in Agarwal et al. (2007). For the numerical simulation, the collocation method implemented in our MATLAB code bvpsuite has been applied.

Choosing a major is part of liberal arts (LA) education in American-accredited colleges across the world. In global second-language (L2) contexts, the choice of major is shaped by local cultural factors. This study of 192 undergraduates at an English-medium-of-instruction (EMI) college in the Republic of the Marshall Islands (RMI) used a survey, content and Appraisal analyses to explore what the LA major means to RMI youth. Results showed they were positive about LA, but little engaged with it outside the classroom. This probably reflected the institution's traditional concept of LA and outdated western teaching approaches, and a failure to incorporate elements of an authentic local culture of teaching and learning. Appraisal data indicated participants associated positive, congruent desire, interest and affection for the LA major, but also low utility and worth with LA class content, revealing a need to convey the utility of the LA skill set for employment. Finally, LA majors were intrinsically, whereas education, business and nursing majors were pragmatically motivated, reflecting the colonial heritage. Overall, results foreground the colonial character of current teaching practice, and the need to use authentic teaching and learning modalities, to support RMI students' pragmatic needs, particularly given their emigration prospects.

The frequency of snowfall and rainfall is expected to change due to the warming climate. However, trends in liquid and solid phases are not linearly related to air temperature trends. This paper discusses the impact of thermal properties of circulation types (CTs) on the trends in snowy and rainy days in Poland in the period 1966–2020. The visual observations from 42 synoptic stations, which constitute the most-reliable information on precipitation type, were used to identify the precipitation phase. In most CTs, the air temperature increased between 1966–1985 and 2001–2020, but at various rates depending on the type of circulation. Positive tendencies in the thermal properties of CTs contributed to decreasing trends in winter snowfall and increasing trends in winter rainfall. The rate of tendencies in the probability of the precipitation phases depended on the average temperature and the intensity of warming, in particular CTs. In winter, both the snowfall and rainfall tendencies were the strongest for those CTs with average air temperatures (ATs) close to the freezing point, particularly when the average had crossed that threshold between the years 1966–1985 and 2001–2020. The most rapid tendencies in winter snowfall and rainfall, and in the spring mixed phase were induced by N and NW air advection under cyclonic conditions, bringing air from the rapidly warming Arctic. No trends in the winter mixed precipitation probability resulted from its various tendencies in particular CTs. The probability of snowfall increased during air advection from the southeastern sector, particularly in winter. [ABSTRACT FROM AUTHOR]

Plant pathogenic nematodes play an important role in crop production and are difficult to control. One of them is Heterodera schachtii—a cyst nematode, pathogenic to sugar beet. Nature suggests a natural way to resolve this problem by using nematode-trapping fungi, one of which is Pleurotus ostreatus. It is one of the most widespread mushrooms in the world. It is a valuable and widely cultivated edible mushroom with nematocidal properties. The mycelium of this mushroom produces toxin droplets that paralyze nematodes, after which the nematodes become infected with the hyphae filament, resulting in their death. This feature can be put to practical use as a natural nematocidal agent. In this paper, we have described studies on the variability of the nematocidal properties in the progeny of three wild strains of P. ostreatus (Po1, Po2, Po4), obtained by crossing dikaryons with monokaryons (Buller phenomenon). The toxicity of mycelium was tested against the model organism Caenorhabditis elegans and against sugar beet pest—H. schachtii. The results of the study allowed the selection of the progeny heterokaryotic mycelia with the best parameters useful for in vitro control of both nematodes. They differed in the activity against C. elegans and H. schachtii, and in the toxic knobs production. The results indicated that the progeny of the Po1 strain presented a good ability to produce hyphal knobs in the presence of C. elegans, and progenies of the Po4 strain presented good quality of growth in preferred temperatures (10–25 °C). Three strains Po1 5dix27, Po2 20dix21, and Po4 2dix1, as well as a maternal strain Po4 controlled H. schachtii by entwining cysts better than other strains. These strains were moderately effective against C. elegans. Strains Po2 15dix17, Po4 1dix18, and Po4 1dix30 may be considered good controlling isolates against both tested organisms. The results of the research also clearly suggest that the killing properties of P. ostreatus mycelia should not be assessed only by their ability to produce toxic hyphal knobs. Their nematocidal properties also depend on other mechanisms developed by mycelia, which is observed as the lethality of nematodes. The results of this research will lead to a natural way to protect plants against nematodes. The research also proved the nematocidal properties of the wild strains to reduce the H. schachtii population in the soil. [ABSTRACT FROM AUTHOR]

Paraphilia is a condition in which the sexual excitement relies on fantasizing and/or participating in unusual sexual behaviors although the line between "normal" and "abnormal" has been disputed. The project aimed to explore which sexual fantasies and behaviors are common and uncommon in the general population. Furthermore, the relationship between sexual fantasies, sexual behaviors, and problematic pornography consumption was examined. Finally, the impact of gender was assessed. Analyses were conducted on a sample of 139 participants. Correlations were found between fantasies, behaviors, and problematic pornography consumption. Furthermore, gender differences were found for both sexual fantasies and problematic pornography consumption. Finally, multiple regression revealed that age, gender [Men], fantasies, and behaviors were significant predictor of problematic pornography consumption. Those findings are in-line with previous studies which highlighted that the threshold to consider a sexual practice as being abnormal needs to be reconsidered on the basis of self-reported fantasies and behaviors in the general population. [ABSTRACT FROM AUTHOR]