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We present the results of modelling of the radio spectrum evolution and dispersion measure variations of PSR B1259-63, a pulsar in a binary system with Be star LS 2883.We base our model on a hypothesis that the observed variations of the spectrum are caused by thermal free-free absorption occurring in the pulsar surroundings. We reproduce the observed pulsar spectral shapes in order to examine the influence of the stellar wind of LS 2883 and the equatorial disc on the pulsar’s radiation.The simulations of the pulsar’s radio emission and its consequent free-free absorption give us an insight into the impact of stellar wind and equatorial disc of LS 2883 has on the shapes of PSR B1259-63 radio spectra, providing an evidence for the connection between gigahertz-peaked spectra phenomenon and the close environment of the pulsar. Additionally, we supplement our model with an external absorbing medium, which results in a good agreement between simulated and observational data. [ABSTRACT FROM AUTHOR]

The core component width in normal pulsars, with periods (P) > 0.1 s, measured at the half-power point at 1 GHz, has a lower boundary line (LBL) that closely follows the P−0.5 scaling relation. This result is of fundamental importance for understanding the emission process and requires extended studies over a wider frequency range. In this paper we have carried out a detailed study of the profile component widths of 123 normal pulsars observed in the Meterwavelength Single-pulse Polarimetric Emission Survey at 333 and 618 MHz. The components in the pulse profile were separated into core and conal classes. We found that at both frequencies, the core, as well as the conal component widths versus period, had a LBL that followed the P−0.5 relation with a similar lower boundary. The radio emission in normal pulsars has been observationally shown to arise from a narrow range of heights around a few hundred kilometers above the stellar surface. In the past the P−0.5 relation has been considered as evidence for emission arising from last open dipolar magnetic field lines. We show that the P−0.5 dependence only holds if the trailing and leading half-power points of the component are associated with the last open field line. In such a scenario we do not find any physical motivation that can explain the P−0.5 dependence for both core and conal components as evidence for dipolar geometry in normal pulsars. We believe the period dependence is a result of a currently unexplained physical phenomenon. [ABSTRACT FROM AUTHOR]

Investigations were carried out in Niepruszewskie and Tomickie polymictic lakes located in Central -West Poland in the water district of Warta. Both lakes are natural, shallow, and characterised by an elongated shape and agricultural use of the catchment area. In total, 18 and 14 sediment samples were collected in Niepruszewskie and Tomickie lakes, respectively, and have been tested for pH, electrical conductivity (EC), and heavy metals Cu, Zn, Pb and Cd. Geoaccumulation index (Igeo), contamination factor (Cf), and the degree of contamination (Cdeg) were calculated in order to assess the whole contamination state of sediments. Results have shown that the average concentrations of Cu, Zn and Pb exceeded the geochemical background values suggested for sediments assessment in Poland. Data have revealed that, in the case of the Niepruszews-kie Lake, Cu, Pb, Cd contents exceeded the geochemical background, except Zn. A similar trend was observed for the Tomickie Lake, where Cd appeared as the main sediment contaminant. Geoaccumulation indices calculated for the particular metals indicate that the class 0 (Igeo 0, sediment not contaminated) and the class I (0 8) for the Niepruszewskie Lake as compared to the Tomickie Lake, where this share raised up to 64%. The contribution of Pb and Cd to the overall contamination was much more pronounced, but for Cu, it was moderate. Zinc was the sole metal to threaten the least both investigated lakes. [ABSTRACT FROM AUTHOR]

Measurement results of barium sulphate reaction crystallization kinetics are presented. The experiments were carried out in the crystallizer with internal circulation of suspension. The crystallizer was continuously fed with barium chloride solution (of concentration 24.0 mass%) and stoichiometrically equivalent amount of crystalline ammonium sulphate. The BaSO4 crystals’ nucleation and growth rates were estimated from the crystal size distributions (CSDs) taking into account a size dependent growth (SDG). The research results may be utilised in the technology of used quenching salts’ processing. [Copyright &y& Elsevier]

Key message: Here we report the existence of six putative Dicer-like genes in the Medicago truncatula genome. They are ubiquitously expressed throughout the plant and significantly induced in root nodules. Abstract: Over the past decade, small noncoding RNAs (sncRNA) have emerged as widespread and important regulatory molecules influencing both the structure and expression of plant genomes. One of the key factors involved in sncRNA biogenesis in plants is a group of RNase III-type nucleases known as Dicer-like (DCL) proteins. Based on functional analysis of DCL proteins identified in Arabidopsis thaliana, four types of DCLs were distinguished (DCL1-4). DCL1 mainly produces 21 nt miRNAs. The products generated by DCL2, DCL3, and DCL4 belong to various classes of siRNAs that are 22, 24 and 21 nt in length, respectively. M. truncatula is a model legume plant closely related to many economically important cultivable species. By screening the recent M. truncatula genome assembly, we were able to identify three new DCL genes in addition to the MtDCL1-3 genes that had been earlier characterized. The newly found genes include MtDCL4 and two MtDCL2 homologs. We showed that all six M. truncatula DCL genes are expressed in plant cells. The first of the identified MtDCL2 paralogs encodes a truncated version of the DCL2 protein, while the second undergoes substantial and specific upregulation in the root nodules. Additionally, we identified an alternative splicing variant of MtDCL1 mRNA, similar to the one found in Arabidopsis. Our results indicate that DCL genes are differently activated during Medicago symbiosis with nitrogen fixing bacteria and upon pathogen infection. In addition, we hypothesize that the alternative splicing variant of MtDCL1 mRNA may be involved in tissue-specific regulation of the DCL1 level. [ABSTRACT FROM AUTHOR]

Computed tomography is commonly used in modern medicine, and thus, it is often helpful for medicolegal purposes, especially as part of the antemortem record. The application of postmortem computed tomography and 3D reconstruction of the skull in challenging cases is reported, and its valuable contribution to positive identification is discussed. This paper presents a case in which the body of an unknown individual is identified. Positive identification had not been possible despite a multidisciplinary examination. The postmortem use of computerized tomography and 3D reconstruction of the skull followed by the comparison of individual morphological characteristics of the viscerocranium showed the concordant points between the deceased and a missing person. Finally, superimposition using a 3D-reconstructed skull instead of the skeletonized skull demonstrated an adequate degree of morphological consistency in the facial images of the analyzed individuals that lead to positive identification. It was concluded that where other methods of personal identification had failed, the use of postmortem computed tomography had proved to be instrumental in the positive identification of the deceased. [ABSTRACT FROM AUTHOR]

Abstract: The experimental data concerning the practical solubility, metastable zone width and nucleation kinetics in l(+)-ascorbic acid–methanol–ethanol–water system are presented. Measurements were performed in a laboratory cooled batch crystallizer with internal circulation of suspension. Practical solubility of l(+)-ascorbic acid in water solutions with addition of both methanol and ethanol was determined using the last crystal dissolution method within the temperature range of T =313–353K. Influence of solution composition and its cooling rate on the value of maximal supercooling of the system is presented and discussed. Nucleation kinetics was elaborated with the use of Kubota''s model of stochastic nucleation in the initial seeding system. Parameter values in the kinetic equations were determined with the method of maximal (critical) supercooling of the solution (constant cooling rates from R T =4.17×10−3–33.3×10−3 Ks−1 range were applied). [Copyright &y& Elsevier]

Most women who have had a mastectomy and have not opted for breast reconstruction choose to use an external breast prosthesis. This study aimed to assess the impacts of external breast prostheses on the body postures of women after unilateral mastectomies. An additional aim was to identify whether postural asymmetry depended on the side of mastectomy. This study involved 52 women after unilateral mastectomy and consisted of two parts: (1) anthropometric measurement and (2) assessment of body posture using the moiré topography method. The posturometric indices showed that the body posture of the subjects in the sagittal plane is characterized by forward trunk inclination and a tendency to excessive kyphosis. There were no significant differences between parameters characterizing body posture with and without external breast prosthesis. The lack of external breast prosthesis had a significant effect only on excessive forward trunk inclination. Significant differences were found in the posturometric parameters in the transverse plane between the groups of patients after left- and right-sided mastectomy. The obtained results did not fully confirm the hypothesis that the external breast prosthesis affects the body posture of women after unilateral mastectomy.

Women after mastectomy may decide to either have a breast reconstruction or use an external breast prosthesis., Aim: The aim of the presented research was to evaluate the influence of external breast prosthesis on postural stability in women after mastectomy., Methods and Procedures: In the study 52 women after unilateral mastectomy took part. The study consisted of 4 parts: 1) anthropometric measurements; 2) measurements of upper limb circumference; 3) assessment of weight-bearing (WB); and 4) posturographic tests (PT)., Outcomes and Results: Differences in the arm circumferences on the amputated (A) and non-amputated (NA) sides did not confirm the occurrence of lymphedema in limb on amputated side. The results of the WB between the A and NA body sides in both tested conditions, i.e., with open and closed eyes, showed no significant differences between the test with and without an external prosthesis. No statistically differences have been observed between posturometric parameters with and without breast prosthesis during both PT. In comparing the posturometric parameters between the PT with open and closed eyes, the sway path of the center of pressure was statistically significantly longer when eyes were closed in both conditions, i.e., with and without breast prosthesis., Conclusion and Implications: The finding show that 1) external breast prosthesis does not have a significant influence on the symmetry of loading on the A and NA body sides and on the postural stability of women after unilateral mastectomy and 2) exclusion visual control during PT increases postural instability in women after unilateral mastectomy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Koralewska, Domagalska-Szopa, Łukowski and Szopa.)

The activity and expression of sulfate transporters and adenosine 5'-phosphosulfate (APS) reductase (APR) in plants are modulated by the plant sulfur status and the demand for growth. To elucidate regulatory mechanisms in Chinese cabbage [Brassica pekinensis (Lour.) Rupr.], the interactions between atmospheric H 2 S and sulfate nutrition and the impact on the activity and expression of the Group 1 sulfate transporters and APR were studied. At an ample sulfate supply, H 2 S exposure of Chinese cabbage resulted in a partial decrease of the sulfate uptake capacity, and at concentrations ≥0.25 μL L -1 a decreased expression of Sultr1;2 in the root and APR in the root and shoot. Upon sulfate deprivation there was a more than 3-fold increase in the sulfate uptake capacity of the root, accompanied by an induced expression of Sultr1;1 and an enhanced expression of Sultr1;2 in the root, along with an induction of Sultr1;2 in the shoot. The enhanced sulfate uptake capacity, the expression of the sulfate transporters in the root and the altered shoot-to-root partitioning appearing during sulfate deprivation were not alleviated upon H 2 S exposure and not rapidly affected by sulfate re-supply. Expression of APR was strongly enhanced in the root and shoot of sulfate-deprived plants and decreased again upon H 2 S exposure and sulfate re-supply. The significance of shoot-to-root interaction and sulfate and thiols as regulating signals in the activity and expression of Sultr1;1 and 1;2 is evaluated.