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Infections caused by Lotmaria passim, Crithidia mellificae, Nosema spp. are frequently observed in bee colonies. The aim of this study was to determine the age at which honey bee worker larvae are most susceptible to the above parasites. Three apiaries (group C—central Poland, group E—north-eastern Poland, group S—southern Poland) with the highest number of colonies infected with Nosema spp. were chosen for the study. Six bee colonies were selected in each apiary, and bee workers of different developmental stages were sampled. The presence of parasites was determined by real-time PCR. The results were processed statistically by two-way analysis of variance (ANOVA) and the least significant difference post-hoc test. The relationship between the presence of the parasites and larval age within groups was analyzed statistically. Significant differences (p < 0.05) in the presence of L. passim were found between 10-day-old larvae vs. 4-, 8-, 12-, 16-, 21-day-old bee brood. Differences in the presence of the analyzed parasites in differently aged larvae were also determined between groups. The presence of N. apis in 10-day-old larvae differed significantly (p < 0.05) between groups C and E. The study revealed that apparently, healthy bee colonies can be a source of infection for other colonies and larvae. C. mellificae was not identified in any of the analyzed groups. [ABSTRACT FROM AUTHOR]

Gravads are a traditional type of Scandinavian delicatessen frequently made from salmon. Developing a gravading technology by using other fish like farmed rainbow trout may make gravads more popular in countries without a tradition in this field. The aim of the present study was to investigate the influence of gravading process parameters (composition and proportion of gravading mixture, time and temperature of ripening) on the physicochemical attributes of rainbow trout gravads. The influence of gravading process parameters (time, temperature, and the amount and relative proportions of the added salt-sugar mixture) on the yield and physicochemical attributes (water activity, protein, salt, sugar and dry matter content) of rainbow trout gravads were investigated using response surface methodology. The amount of the added sugar-salt mixture and gravading time were more important factors affecting the analyzed attributes than temperature or the proportions of salt and sugar. Mathematical models were developed to estimate the quality parameters of rainbow trout gravad obtained under different process conditions. Response surfaces representing changes in gravad attributes with varying processing conditions help to make the most desirable product. The results obtained in this work may facilitate the expansion of the range of nutritionally valuable fish products available on the market.

Theoretical structures of copper(II) complexes of cis-1,2-diaminocyclohexane (Dach), [Cu(Dach)2(N3)]Cl·3H2O (1) and [Cu(Dach)2-Ag(CN)2-Cu(Dach)2][Ag(CN)2]3 (2) are predicted by DFT calculations. The DFT results reveal that the experimental structures are better reproduced by the calculations for complexes in a water solvent using the polarizable continuum model (PCM) rather than those performed for the system in the gas phase. Complex 1 was theoretically predicted with better accuracy than complex 2. Atomic charges and spin densities are calculated for the model complexes by the natural bond orbital (NBO) analysis. [ABSTRACT FROM AUTHOR]

Rescue patrol hovercrafts must meet the basic condition – high reliability of use in extreme conditions. The introduction to the work shows damage to the propulsion system and the fan tunnel structure resulting from a fatigue fracture of the attachment wound to the propulsion unit hull. In this paper, the author describes some ways of improving the engine frame structure. In the first phase of the exploitation crack testing of the hovercraft frame, the probable causes of damage were determined. The necessary output data for analysis of the load course were obtained from the operating documentation. The approximate number of variable load cycles acting on the frame truss rod was determined. Using the comparative testing methods, the service life of the frame was estimated. Probable resonance frequencies of the vibrating bars in the truss were determined. Vibration tests of the power transmission assemblies were carried out, which allowed to determine the amplitudes and frequencies of free vibrations. Finally, a modification of the frame shifting the resonant frequency range was proposed. In conclusions, changes to the design and a schedule of inspections were proposed. The newly designed engine frame should have an extended service life.

A cyanido bridged Zn(II)-Ag(I) bimetallic complex (I) has been prepared and characterized by IR spectroscopy, thermal analysis, X-ray crystallography (CIF file CCDC no. 884016) and DFT calculations. Thermal analysis shows that the composition of the compound is consistent with the proposed stoichiometry, i.e., [Zn(diamine)2{Ag(CN)2}2] . H2O. The crystal structure of complex I consists of two independent molecules; a trinuclear molecule, [Zn(Dmen)2{Ag(CN)2}2] and an ionic species, [Zn(Dmen)2-(H2O)2]{Ag(CN)2}2; the overall formula being [Zn(Dmen)2{Ag(CN)2}2][Zn(Dmen)2(H2O)2]{Ag(CN)2}2 (I) (Dmen = N,N'- dimethylethylenediamine). The structures of I and two of its analogues, [Zn(Dmen)2{Ag(CN)2}2]2 . 2H2O (II) and {[Zn(Dmen)2{Ag(CN)2}][Ag(CN)2]}2 . 2H2O (III) were predicted by DFT calculations. The DFT results reveal that the structure I is more stable in comparison to the calculated structures, II and III. The X-ray structure of I shows that the complex is also stabilized by the argentophilic interactions. The Ag...Ag interaction energy calculated at the MP2 level of theory is -4.02 kcal mol-1. [ABSTRACT FROM AUTHOR]

Honey bees (Apis mellifera L.) inhabiting trees in forests are not managed by humans or treated for pathogens; therefore, many researchers and beekeepers believe that viral, bacterial, and parasitic diseases may lead to their decline. The aim of the study was to evaluate the prevalence of L. passim and Nosema spp. in feral colonies by real-time PCR. This study was performed on twenty-six samples of honey bees inhabiting tree trunks in north-eastern Poland. One sample consisted of sixty worker bee abdomens collected from hollow trees. Honey bees were sampled only from naturally colonized sites. Amplicons of the three evaluated pathogens were detected in twenty of the twenty-six tested samples. A significant correlation was observed between infection with three pathogens (N. apis, N. ceranae, L. passim) (r = 0.84) compared to infection with only two pathogens (N. apis and N. ceranae) (r = 0.49). N. ceranae was the predominant pathogen, but infections with various severity caused by L. passim were also noted in fourteen of the twenty-six tested samples. In view of the general scarcity of epidemiological data concerning coinfections with Nosema spp. and L. passim in honey bees in tree trunks in other countries, further research is needed to confirm the effect of concurrent pathogenic infections on the decline of bee colonies.

The development of female Varroa destructor mites in the bee colonies was examined in the apiculture season through a developed research system in which bee colonies were experimentally infested with fifty V. destructor females. Differences in infestation rates were observed between the control group (C) and the infested group (E). The average number of female mites per colony was determined at 513 in group E and 261.6 in group C. Natural daily mortality reached 0.16 mites in group E and 0.09 mites in group C. In group E, the number of V. destructors increased 7.96 to 13.32-fold, subject to colony. The size of V. destructor populations increased at a higher rate in group E than in group C (F= 12.39, P= 0.047). At the end of the experiment, the percentage of infested honey bee workers was determined at 0.97% in group E and 0.46% in group C. The results of this study confirmed that V. destructor mites continue to proliferate rapidly in honey bee colonies, and that the population growth rate in bee colonies and apiaries has to be closely monitored due to growing levels of resistance to acaricides.

Recent years have witnessed an increase in the mortality of honey bees in many regions of the world. The observed decrease in the bee population results from a combination of factors, and microsporidian parasites Nosema apis and N. ceranae are among the main contributors. Those parasites cause a microsporidian infection that shortens the lifespan of bees and reduces the productivity of bee colonies. The aim of this study was to evaluate the effectiveness of Nozevit, Api Herb and ApiX (acetylsalicylic acid + Artemisia absinthium L. extract) in the control of infections caused by Nosema spp. in a field experiment. Two groups of worker bees were evaluated - hive bees and forager bees returning to the hive. The effect of the analyzed therapies on the number of spores and the microsporidia species were analyzed by the hemocytometric method and duplex PCR. A statistical analysis revealed that the applied treatments had reduced the number of spores by 31.15% on average. In hive bees, Nosema spp. infection was most effectively reduced by Nozevit (67.85%) and ApiX (63.36%). Coinfections (N. ceranae and N. apis) were affirmed in all bee samples before treatments. However, after the treatments, single infection of N. apis and N. ceranae were detected. The tested treatments were more effective in the control of N. apis than N. ceranae.

Celem badań było ustalenie, który gatunek Nosema występuje u robotnic Apis mellifera pobieranych z różnych miejsc ula w sezonie pasiecznym. W lutym 2010 roku zbadano osypy zimowe pszczół z 30 rodzin pszczelich. W zależności od stwierdzonego gatunku sporowca (metodą multiplex PCR) dalszą ocenę występowania gatunku sporowców prowadzono w następujących grupach (rodzinach pszczelich bez objawów klinicznych choroby): AC - zainfekowana Nosema apis i Nosema ceranae (infekcja mieszana), A - zainfekowana N. apis, C - zainfekowana N. ceranae oraz grupa kontrolna K, wolna od infekcji. Z każdej rodziny od kwietnia do sierpnia w odstępach 30 dniowych pobierano do badań losowo po 20 robotnic z dwóch miejsc: robotnice ulowe, bezpośrednio z plastrów z czerwiem otwartym oraz robotnice lotne - robotnice powracające do uli z pyłkiem. Wykazaliśmy, że nie tylko rodzaj robotnic (miejsce pobrania), ale i okres (miesiąc) pobrania prób do badań ma wpływ na rodzaj wykrywanego gatunku sporowca, a także, że niezależnie od rodzaju infekcji początkowej (w osypie zimowym) w rodzinach pszczelich mogą współistnieć osobniki zainfekowane różnymi gatunkami sporowca oraz wolne od infekcji.

Theoretical structures of copper(II) complexes of cis-1,2-diaminocyclohexane (Dach), [Cu(Dach)2(N3)]Cl·3H2O (1) and [Cu(Dach)2-Ag(CN)2-Cu(Dach)2][Ag(CN)2]3 (2) are predicted by DFT calculations. The DFT results reveal that the experimental structures are better reproduced by the calculations for complexes in a water solvent using the polarizable continuum model (PCM) rather than those performed for the system in the gas phase. Complex 1 was theoretically predicted with better accuracy than complex 2. Atomic charges and spin densities are calculated for the model complexes by the natural bond orbital (NBO) analysis. [ABSTRACT FROM AUTHOR]

The starting point for this work was a set of crystal structures containing the motif of interaction between methyl groups in homodimers. Two structures were selected for which QTAIM, NCI and NBO analyses suggested an attractive interaction. However, the calculated interaction energy was negative for only one of these systems. The ability of methyl groups to interact with one another is then examined by DFT calculations. A series of (CH 3 PnHCH 3 ) 2 homodimers were allowed to interact with each other for a range of Pn atoms N, P, As, and Sb. Interaction energies of these C⋅⋅⋅C tetrel-bonded species were below 1 kcal/mol, but could be raised to nearly 3 kcal/mol if the C atom was changed to a heavier tetrel. A strengthening of the C⋅⋅⋅C intermethyl bonds can also be achieved by introducing an asymmetry via an electron-withdrawing substituent on one unit and a donor on the other. The attractions between the methyl and related groups occur in spite of a coulombic repulsion between σ-holes on the two groups. NBO, AIM, and NCI tools must be interpreted with caution as they can falsely suggest bonding when the potentials are repulsive., (© 2024 Wiley-VCH GmbH.)

Background: DNA methylation profiling may provide a more accurate measure of the smoking status than self-report and may be useful in guiding clinical interventions and forensic investigations. In the current study, blood DNA methylation profiles of nearly 800 Polish individuals were assayed using Illuminia EPIC and the inference of smoking from epigenetic data was explored. In addition, we focused on the role of the AHRR gene as a top marker for smoking and investigated its responsiveness to other lifestyle behaviors., Results: We found > 450 significant CpGs associated with cigarette consumption, and overrepresented in various biological functions including cell communication, response to stress, blood vessel development, cell death, and atherosclerosis. The model consisting of cg05575921 in AHRR (p = 4.5 × 10 -32 ) and three additional CpGs (cg09594361, cg21322436 in CNTNAP2 and cg09842685) was able to predict smoking status with a high accuracy of AUC = 0.8 in the test set. Importantly, a gradual increase in the probability of smoking was observed, starting from occasional smokers to regular heavy smokers. Furthermore, former smokers displayed the intermediate DNA methylation profiles compared to current and never smokers, and thus our results indicate the potential reversibility of DNA methylation after smoking cessation. The AHRR played a key role in a predictive analysis, explaining 21.5% of the variation in smoking. In addition, the AHRR methylation was analyzed for association with other modifiable lifestyle factors, and showed significance for sleep and physical activity. We also showed that the epigenetic score for smoking was significantly correlated with most of the epigenetic clocks tested, except for two first-generation clocks., Conclusions: Our study suggests that a more rapid return to never-smoker methylation levels after smoking cessation may be achievable in people who change their lifestyle in terms of physical activity and sleep duration. As cigarette smoking has been implicated in the literature as a leading cause of epigenetic aging and AHRR appears to be modifiable by multiple exogenous factors, it emerges as a promising target for intervention and investment., (© 2024. The Author(s).)

Halonium cations can interact through a halogen bond with individual noble gas atoms. These bonds can vary widely in strength from 1 to 25 kcal mol -1 . Quantum chemical analyses consider X to be attached to a propyl group, pyridine N, or Xe atom, with X = Cl, Br, and I, interacting with Ar, Kr, and Xe atoms. The most weakly bound dyads are bound primarily by electrostatics, but charge transfer takes a larger role for the more tightly held complexes.

There is considerable interest in the use of essential oils for food preservation, but their effect on the aroma profile of a product is poorly understood. This study investigated the effect of thyme essential oil (EO) addition at increasing concentrations (0.005, 0.01, 0.02, and 0.03% v / w ) on the volatile compound composition of vacuum-packed minced turkey meat after storage for 8 days at 1-2 °C. The aroma profile of the meat was determined using the HS-SPME/GCMS (headspace solid-phase microextraction/gas chromatography-mass spectrometry) method. The results were also analysed by PCA (principal component analysis). The addition of thyme EO had a modifying effect on the aroma profile of meat-derived components, e.g., the formation of benzeneacetaldehyde, benzyl alcohol, 4,7-dimethylbenzofuran, hexathiane, hexanal, and 1-hexanol was reduced and the appearance of 9-hexadecenoic acid was observed in the stored samples. The increase in EO concentration affected the levels of its individual components in the meat headspace in different ways. In terms of fat rancidity indices, even a 0.005% addition of this essential oil significantly reduced the peroxide value. Quantitative descriptive analysis (QDA) showed that the addition of thyme EO reduced or masked the intensity of unpleasant odours associated with meat spoilage. In the aroma analysis, the turkey with 0.02% v / w EO scored highest, and pleasant citrus notes were found.

DNA methylation (DNAm) clocks hold promise for measuring biological age, useful for guiding clinical interventions and forensic identification. This study compared the commonly used DNAm clocks, using DNA methylation and SNP data generated from nearly 1000 human blood or buccal swab samples. We evaluated different preprocessing methods for age estimation, investigated the association of epigenetic age acceleration (EAA) with various lifestyle and sociodemographic factors, and undertook a series of novel genome-wide association analyses for different EAA measures to find associated genetic variants. Our results highlighted the Skin&Blood clock with ssNoob normalization as the most accurate predictor of chronological age. We provided novel evidence for an association between the practice of yoga and a reduction in the pace of aging (DunedinPACE). Increased sleep and physical activity were associated with lower mortality risk score (MRS) in our dataset. University degree, vegetable consumption, and coffee intake were associated with reduced levels of epigenetic aging, whereas smoking, higher BMI, meat consumption, and manual occupation correlated well with faster epigenetic aging, with FitAge, GrimAge, and DunedinPACE clocks showing the most robust associations. In addition, we found a novel association signal for SOCS2 rs73218878 (p = 2.87 × 10 -8 ) and accelerated GrimAge. Our study emphasizes the importance of an optimized DNAm analysis workflow for accurate estimation of epigenetic age, which may influence downstream analyses. The results support the influence of genetic background on EAA. The associated SOCS2 is a member of the suppressor of cytokine signaling family known for its role in human longevity. The reported association between various risk factors and EAA has practical implications for the development of health programs to improve quality of life and reduce premature mortality associated with age-related diseases., (© 2023. The Author(s), under exclusive licence to American Aging Association.)

A growing body of evidence indicates an important role of miRNAs in cancer; however, there is no definitive, convenient-to-use list of cancer-related miRNAs or miRNA genes that may serve as a reference for analyses of miRNAs in cancer. To this end, we created a list of 165 cancer-related miRNA genes called the Cancer miRNA Census (CMC). The list is based on a score, built on various types of functional and genetic evidence for the role of particular miRNAs in cancer, e.g. miRNA-cancer associations reported in databases, associations of miRNAs with cancer hallmarks, or signals of positive selection of genetic alterations in cancer. The presence of well-recognized cancer-related miRNA genes, such as MIR21, MIR155, MIR15A, MIR17 or MIRLET7s, at the top of the CMC ranking directly confirms the accuracy and robustness of the list. Additionally, to verify and indicate the reliability of CMC, we performed a validation of criteria used to build CMC, comparison of CMC with various cancer data (publications and databases), and enrichment analyses of biological pathways and processes such as Gene Ontology or DisGeNET. All validation steps showed a strong association of CMC with cancer/cancer-related processes confirming its usefulness as a reference list of miRNA genes associated with cancer., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The term "wolfium bond" has been recently introduced to describe the noncovalent attraction between an atom of group 6 and a nucleophile via a σ-hole binding site. Crystal structures commonly contain a motif wherein two MX 4 Y units are arranged in close proximity, where M represents either Mo or W, and X and Y refer to halogen and chalcogen atoms respectively. DFT calculations were thus applied to a wide range of homodimers of these molecules so as to assess their preferred arrangements, and to characterize the types of bonding that are present in each in a systematic manner. The most stable Dual-X configuration is symmetric and contains a pair of equivalent M⋯X bonds. The interaction energies range from -8 to -29 kcal mol -1 , and are largest for X = F, Y = O, and M = W. The X electron donor is replaced by Y, and the two wolfium bonds are reduced to one, in the less stable Mono-Y structure, with interaction energies between -2 and -10 kcal mol -1 . There is some question as to whether the weaker bonds of this type constitute true wolfium bonds.