Ischemic heart disease in nuclear workers first employed at the Mayak PA in 1948-1972

Following an earlier study of incidence and mortality of ischemic heart disease (IHD) published in 2010, a second analysis has been conducted based on an extended cohort and five additional years of follow-up. The cohort includes 18,763 workers, of whom 25% were females, first employed at the Mayak PA in 1948-1972 and followed up to the end of 2005. Some of these workers were exposed to external gamma rays only, and others were exposed to a mixture of external gamma-rays and internal alpha-particle radiation. A total of 6,134 cases and 2,629 deaths from IHD were identified in the study cohort. A statistically significant increasing trend was found with total external gamma-ray dose in IHD incidence (ERR/Gy 0.099; 95% CI: 0.045-0.153) after adjusting for non-radiation factors. This value reduced slightly when adjusting for internal liver dose. There was no statistically significant increase trend for internal liver dose in IHD incidence. These findings were consistent with an earlier study. New findings in IHD incidence revealed a statistically significant decrease in IHD incidence among workers exposed to external gamma-rays doses of 0.2-0.5 Gy in relation to the external doses below 0.2 Gy. This decreased risk is heavily influenced by female workers. This finding has never been reported in other studies, and the results should be treated with caution. The findings for IHD mortality are similar to those results in the earlier analysis; there was no statistically significant trend with external gamma-ray dose or for internal liver dose after adjustment for external dose. The risk estimates obtained from these analyses of IHD incidence and mortality in relation to external gamma-rays in the cohort of Mayak workers are generally compatible with those from other large occupational radiation worker studies and the Japanese atomic bomb survivors.     

Agentive and communitarian play in early childhood

Play has long been recognised as a vehicle by which significant developmental advances occur during early childhood. Children use play to explore their relationships, their psychosocial skills, and their environment, and through their experiences, they begin to adopt specific capacities and values that have an impact on future socio-emotional and academic outcomes. To understand more fully the factors that contribute to well-being in early childhood, we explored footage of a full ‘day in the life’ of a 5-year-old boy in transition to kindergarten, and we conducted interviews with him, his parents, and teacher. We identified agentive and communitarian strivings to be significant sources of his thriving and primary elements of many episodes of play during his filmed day. Previous research indicates that the development of strong agentive and communitarian skills and values is related to positive psychosocial outcomes. The current case study explores our participant's agentive and communitarian behaviours as exemplified through episodes of play, and the ways in which these skills and values are encouraged and supported by his caregivers. Implications regarding the role of parents and educators in the facilitation of agentive and communitarian skills are discussed.     

Fused Thiopyrano[2,3-d]thiazole Derivatives as Potential Anticancer Agents

rel-(5aR,11bR)-3,5a,6,11b-tetrahydro-2H,5H-chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazol-2-ones formed by the stereoselective Knoevenagel-hetero-Diels-Alder reaction were functionalized at the nitrogen in position 3 via reactions of alkylation, cyanoethylation, and acylation. The synthesized compounds were evaluated for their anticancer activity in NCI60 cell lines. Among the tested compounds, 3f was found to be the most active candidate with the greatest influence on leukemia, non-small cell lung cancer, colon cancer, CNS cancer, melanoma, prostate cancer, and breast cancer subpanel cell lines with GI₅₀ values over a range of 0.37–0.67 μM.     

Insight into the active site nature of zeolite H-BEA for liquid phase etherification of isobutylene with ethanol

The nature of active acid sites of zeolite H-BEA with different Si/Al ratios (15–407) in liquid phase etherification of isobutylene with ethanol in a continuous flow reactor in the temperature range 80–180 °C has been explored. We describe and discuss data concerning the strength and concentration of acid sites of H-BEA obtained by techniques of stepwise (quasi-equilibrium) thermal desorption of ammonia, X-ray diffraction, low-temperature adsorption of nitrogen, FTIR spectroscopy of adsorbed pyridine and solid-state ²⁷Al MAS NMR. The average values of the adsorption energy of NH₃ on H-BEA were experimentally determined as 63.7; 91.3 and 121.9 mmol g⁻¹ (weak, medium, and strong, respectively). In agreement with this, a correlation between the rate of ethyl-tert-butyl ether synthesis and the concentration of weak acid sites (E_NH3 = 61.6–68.9 kJ mol⁻¹) has been observed. It was concluded that the active sites of H-BEA for this reaction are Brønsted hydroxyls representing internal silanol groups associated with octahedrally coordinated aluminum in the second coordination sphere.

The active sites of H-BEA zeolites for ETBE synthesis are the weak Brønsted acid sites representing internal silanol groups.     

A graphene-based hybrid material with quantum bits prepared by the double Langmuir–Schaefer method

The scalability and stability of molecular qubits deposited on surfaces is a crucial step for incorporating them into upcoming electronic devices. Herein, we report on the preparation and characterisation of a molecular quantum bit, copper(ii)dibenzoylmethane [Cu(dbm)₂], deposited by a modified Langmuir–Schaefer (LS) technique onto a graphene-based substrate. A double LS deposition was used for the preparation of a few-layer-graphene (FLG) on a Si/SiO₂ substrate with subsequent deposition of the molecules. Magnetic properties were probed by high-frequency electron spin resonance (HF-ESR) spectroscopy and found maintained after deposition. Additional spectroscopic and imaging techniques, such as Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were performed to characterise the deposited sample. Our approach demonstrated the possibility to utilise a controlled wet-chemistry protocol to prepare an array of potential quantum bits on a disordered graphene-based substrate. The deployed spectroscopic techniques showed unambiguously the robustness of our studied system with a potential to fabricate large-scale, intact, and stable quantum bits.

Graphene-based hybrid material with array of copper(ii)-based quantum bits was prepared by a wet-chemistry protocol and characterised by HF-ESR, XPS, Raman, and AFM.     

Receptor-like cytoplasmic kinase MARIS functions downstream of CrRLK1L-dependent signaling during tip growth

Growing plant cells need to rigorously coordinate external signals with internal processes. For instance, the maintenance of cell wall (CW) integrity requires the coordination of CW sensing with CW remodeling and biosynthesis to avoid growth arrest or integrity loss. Despite the involvement of receptor-like kinases (RLKs) of the Catharanthus roseus RLK1-like (CrRLK1L) subfamily and the reactive oxygen species-producing NADPH oxidases, it remains largely unknown how this coordination is achieved. ANXUR1 (ANX1) and ANX2, two redundant members of the CrRLK1L subfamily, are required for tip growth of the pollen tube (PT), and their closest homolog, FERONIA, controls root-hair tip growth. Previously, we showed that ANX1 overexpression mildly inhibits PT growth by oversecretion of CW material, whereas pollen tubes of anx1 anx2 double mutants burst spontaneously after germination. Here, we report the identification of suppressor mutants with improved fertility caused by the rescue of anx1 anx2 pollen tube bursting. Mapping of one these mutants revealed an R240C nonsynonymous substitution in the activation loop of a receptor-like cytoplasmic kinase (RLCK), which we named MARIS (MRI). We show that MRI is a plasma membrane-localized member of the RLCK-VIII subfamily and is preferentially expressed in both PTs and root hairs. Interestingly, mri-knockout mutants display spontaneous PT and root-hair bursting. Moreover, expression of the MRI^R240C mutant, but not its wild-type form, partially rescues the bursting phenotypes of anx1 anx2 PTs and fer root hairs but strongly inhibits wild-type tip growth. Thus, our findings identify a novel positive component of the CrRLK1L-dependent signaling cascade that coordinates CW integrity and tip growth.Growing plant cells are in constant communication with their environment, monitoring external signals that lead to internal reactions. Because cellular growth depends on a tight coordination of external and internal processes, signaling between the extracellular matrix, i.e., the primary cell wall (CW), and the internal growth machinery plays a central role in its regulation. The turgor pressure-resisting CW that shields plant cells from a changing environment exhibits remarkable but seemingly contradictory properties: rigidity and extensibility. Growing cells must find a balance between loosening their CWs sufficiently to allow expansion but not so much that they lose CW integrity. Because any environmental perturbation affecting the properties of the CW can upset this fragile balance, plant cells have developed complex sensing mechanisms to coordinate the state of the CW with the internal growth machinery (1, 2). These CW sensing mechanisms must be particularly robust in fast-growing cells, such as the tip-growing root hairs and pollen tubes (PTs), the male gametophytes of flowering plants. PTs elongate rapidly and grow over long distances within female tissues to deliver the sperm cells to the female gametophytes, which are deeply embedded in the ovules. Considering the vast excess of pollen grains that germinate on a receptive stigma, there is strong competition, and PTs must grow as fast as possible to reach unfertilized ovules; otherwise they will not contribute to the next generation. However, PTs must ensure that, while elongating extremely rapidly, they do not lose their integrity. In PTs of the model plant Arabidopsis thaliana, the plasma membrane-localized ANXUR (ANX1 and ANX2) receptor-like kinases (RLKs) play a major role in controlling CW integrity and growth. On one hand, loss of function of the redundant RLKs ANX1 and ANX2 leads to precocious PT rupture shortly after germination, resulting in male sterility (3, 4). This phenotype also is seen when the ANX-RLKs are degraded by the endoplasmic reticulum-associated degradation pathway in the turan mutant affecting N-glycosylation (5). On the other hand, overexpression of ANX-RLKs inhibits pollen germination and PT elongation, most likely because of the oversecretion of CW material (6). The ANX-RLKs and their closest homolog FERONIA (FER) belong to the Catharanthus roseus RLK1-like (CrRLK1L) subfamily that has been investigated extensively as putative CW sensors involved in coordinating cell growth, cell–cell communication, defense against pathogens, and hormone signaling as well as CW remodeling and integrity (reviewed in refs. 7–9). FER, the most thoroughly studied member of this subfamily, controls many developmental processes, such as intercellular communication during fertilization (10–12), cell elongation (13), calcium and hormone signaling (10, 14, 15), mechanosensing (16), plant defense (17, 18), and growth control of root hairs (19). Despite the many reports describing the role of CrRLK1Ls in various signaling processes, the mechanistic basis of their function and their relationship with other pathways remain poorly understood. FER was recently found to mediate the inhibition of primary root growth by forming a receptor–ligand pair with the rapid alkalinization factor 1 (RALF1) peptide (20). Moreover, it was shown that the intracellular kinase domains of three CrRLK1Ls members are interchangeable and that the various CrRLK1Ls share downstream signaling components (21). This finding has been confirmed for at least one signaling component so far, namely the reactive oxygen species (ROS)-producing NADPH oxidases, also called “respiratory burst oxidase homologs” (Rboh). It was reported that RbohD/RbohF for THESEUS1 (THE1), RbohC for FER, and RbohH/RbohJ for ANX1/2 act downstream of the CrRLK1Ls in primary roots, root hairs, and PTs, respectively (6, 19, 22).Here, we report, based on an anx1 anx2 male sterility suppressor screen, the identification of the receptor-like cytoplasmic kinase (RLCK) MARIS (MRI), a novel component of the CrRLK1L-mediated signaling pathway in tip-growing cells. MRI is expressed preferentially in PTs and root hairs, and its disruption triggers spontaneous bursting of PTs and root hairs. The suppressor mutant carries a R240C amino acid substitution in the activation loop of MRI. Expression of MRI^R240C partially rescues the bursting phenotypes of anx1 anx2 and rbohH rbohJ PTs as well as fer root hairs while strongly inhibiting WT tip growth, indicating that this mutant form of MRI overactivates the CrRLK1L-dependent pathway downstream of the NADPH oxidases.