This work presents the first direct measurement of the 93Mo half-life. The measurement is a combination of high-resolution mass spectrometry for the determination of the 93Mo concentration and liquid scintillation counting for determining the specific activity. A 93Mo sample of high purity was obtained from proton irradiated niobium by chemical separation of molybdenum with a decontamination factor larger than 1.6 × 1014 with respect to Nb. The half-life of 93Mo was deduced to be 4839(63) years, which is more than 20% longer than the currently adopted value, whereas the relative uncertainty could be reduced by a factor of 15. The probability that the 93Mo decays to the metastable state 93mNb was determined to be 95.7(16)%. This value is a factor of 8 more precise than previous estimations. Due to the man-made production of 93Mo in nuclear facilities, the result leads to significantly increased precision for modelling the low-level nuclear waste composition. The presented work demonstrates the importance of chemical separations in combination with state-of-the-art analysis techniques, which are inevitable for precise and accurate determinations of nuclear decay data.
Usklađivanje privatnog života koji uključuje prije svega majčinstvo, brigu o djeci, kući i brojne druge obveze, i profesionalnog života koji obuhvaća obrazovanje, zapošljavanje, usavršavanje i posvećenost poslu, predstavlja iznimno složen problem s kojim se susreću žene na području rada i radnih odnosa. U današnje vrijeme žene su postale dvostruko ili višestruko opterećene. Pred njih se stavlja svojevrstan izbor između privatnog i profesionalnog života te ih se izlaže životnim izborima i izazovima koji nisu svojstveni muškarcima. Stoga žene radnice sve češće koriste minimum rodiljnog dopusta, a brigu o djeci, obitelji i domu prepuštaju drugim osobama ili ustanovama samo kako bi zadržale posao i omogućile profesionalno usavršavanje i napredovanje. Zbog konstantne izloženosti pritiscima i očekivanjima kako na planu privatnog, tako i na planu profesionalnog života istovremeno, kod žena radnica mogu se razviti određeni poremećaji i stanja koja u značajnoj mjeri mogu utjecati na njihovo mentalno zdravlje. Važeći propisi u Bosni i Hercegovini pružaju minimum prava, ali nedovoljno za uspostavljanje adekvatnog balansa između privatnog i profesionalnog života žena radnica.
Background. Immunocompromised individuals are highly susceptible to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Whether vaccine-induced immunity in these individuals involves the oral cavity, a primary site of infection, is presently unknown. Methods. Immunocompromised individuals (n=404) and healthy controls (n=82) participated in a prospective clinical trial encompassing two doses of the mRNA BNT162b2 vaccine. Immunocompromised individuals included primary immunodeficiencies (PID) and secondary immunodeficiencies caused by human immunodeficiency virus (HIV) infection, allogeneic hematopoietic stem cell transplantation (HSCT)/chimeric antigen receptor T cell therapy (CAR-T), solid organ transplantation (SOT), and chronic lymphocytic leukemia (CLL). Saliva and serum samples were collected at four time points from the first vaccine dose until 2 weeks after second dose. SARS-CoV-2 spike specific immunoglobulin G (IgG) responses were quantified by a multiplex bead-based assay in saliva and correlated to paired serum IgG titers determined by Elecsys Anti-SARS-CoV-2 S assay. Results. IgG responses to the SARS-CoV-2 spike full-length trimeric glycoprotein (Spike-f) and S1 subunit in saliva in the HIV and HSCT/CAR-T groups were comparable to healthy controls. In contrast, PID, SOT, and CLL patients all displayed weaker responses which were mainly influenced by disease parameters or immunosuppressants. Salivary IgG levels strongly correlated with serum IgG titers on days 21 and 35 (rho=0.8079 and 0.7768, p=<0.0001). Receiver operating characteristic curve analysis for the predictive power of salivary IgG yielded AUC=0.95, PPV=90.7% for the entire cohort on D35. Conclusions. Saliva conveys humoral responses induced by BNT162b2 vaccination. The predictive power makes it highly suitable for screening low responding/vulnerable groups for revaccination.
Introduction: The way of life in modern society goes along with new technological discoveries and achievements. This lifestyle leaves its positive and negative consequences on children. Such changes are especially reflected on health already in earliest stages of life. The studies show that most children have been using computers even since kindergarten and that children’s computer use is longer than recommended. It is more effective and cheaper to prevent musculoskeletal disorders than to cure them. Goal: To examine all risk factors concerning the development of musculoskeletal disorders connected with a long use of information and communication technologies by reviewing scientific literature. Material and methods: Non-experimental qualitative research into the risk factors of the development of musculoskeletal disorders connected with a long use of information and communication technologies based on relevant databases. Results and discussion: Based on a discussion of the attitudes and opinions of other authors, risk factors are divided in three basic groups: ergonomic, individual, and psychosocial risk factors. As it is shown in the discussion of this paper, a disbalance of the desk for a desktop computer, the non-ergonomic design of the furniture, the type and time of the ICT usage device, the sedentary way of using the ICT devices at school and at home are just some of the numerous risk factors to children’s health. Conclusion: By examining the risk factors in the development of musculoskeletal disorders in children connected with an extended use of information and communication technologies, the presented evidence in the discussion section based on other authors’ attitudes and opinions, leads us to the conclusion that numerous risk factors that affect children’s health are due to a larger and more frequent use of computers, console games, tablets and mobile phones.
Phytoremediation has proven to be a suitable method for removing heavy metals from the soil with the help of plants. To examine the phytoremediation potential, the experimental study monitored the influence of high and low concentrations of heavy metals (Pb, Cd, and Zn) on Helianthus annuus L., as well as their accumulation in seeds, roots, stems and leaves. The experiment was carried out during one growing season in outdoor conditions, in pots with a volume of 5L in which Helianthus annuus L. was planted, and the soil was contaminated with these heavy metals in concentrations below and above the maximum allowable concentration prescribed by the Rulebook on Determining Permissible Quantities of Harmful and Dangerous Substances in Soil and Methods of Their Testing. After growth and development of the plant, the experimental research examined the accumulation potential of the plant, the growth of the plant itself and its ability to survive depending on different concentrations of heavy metals. By processing the obtained results, statistically significant differences of heavy metals were determined in individual parts of the plants, depending on the applied concentration. The highest concentration of Zn was recorded in the leaves of the plant in the amount of 18.21 mg/kg, and the lowest concentration in the stem, 3.92 mg/kg. The measured values of heavy metals Cd and Pb differ from the above because the lowest concentrations of these heavy metals were recorded in the seed, and were 12.02 mg/kg for Pb and 9.20 mg/kg for Cd, which is a statistically significantly lower determined value relative to other parts of the plant.
Background High-throughput assays for the detection of SARS-CoV-2 variants of concern (VOC) and interest (VOI) are a diagnostic alternative when whole genome sequencing (WGS) is unavailable or limited. Objective This study evaluated the clinical and analytical performance of the Seegene Allplex™ SARS-CoV-2 Variants I assay, which detects the HV69/70 deletion, N501Y and E484K mutations of the S gene. Methods Genotyping was evaluated on -871 SARS-CoV-2 RNA positive specimens, 408 nasopharyngeal (NP) swabs and 463 saline gargle (SG) specimens, with WGS used as the reference standard. Analytical performance was assessed including stability, reproducibility, limit of detection (LOD), cross-reactivity and interference with various respiratory microorganisms. Results The clinical study revealed sensitivity of 100% (95% CI 99.27%–100%) and specificity of 100% (95% CI 98.99%–100%) for HV69/70 deletion, sensitivity of 100% (95% CI 99.55%–100%) and specificity of 100% (95% CI 93.73% – 100%) for N501Y, and sensitivity of 100% (95% CI 98.94% – 100%) and specificity of 98.10% (95% CI 96.53% – 99.08%) for E484K mutation. The E484Q mutation was detected in 10 specimens of the Kappa variant (B.1.627.1). Analytical performance demonstrated stability and reproducibility over 7 days, and LOD was calculated at 698 cp/mL for NP swab specimens, and 968 cp/mL for SG specimens. No interference or cross-reactivity with other microorganisms was noted. Conclusion The Allplex™ SARS-CoV-2 Variants I assay is acceptable for clinical use for the detection of variant of concern and variant of interest.
An increasing evidence suggests that vanadium compounds are novel potential drugs in the treatment of diabetes, atherosclerosis, and cancer. Vanadium has also demonstrated activities against RNA viruses and is a promising candidate for treating acute respiratory diseases. The antidiabetic, antihypertensive, lipid-lowering, cardioprotective, antineoplastic, antiviral, and other potential effects of vanadium are summarized here. Given the beneficial antihyperglycemic and antiinflammatory effects as well as the potential mechanistic link between the COVID-19 and diabetes, vanadium compounds could be considered as a complement to the prescribed treatment of COVID-19. Thus, further clinical trials are warranted to confirm these favorable effects of vanadium treatment in COVID-19 patients, which appear not to be studied yet.
We investigated the role of the gold nanoparticles functionalized with polyvinylpyrrolidone (PVP–AuNPs) on the innate immune response against an acute infection caused by Vibrio anguillarum in an in vitro immunological nonmammalian next-generation model, the sea urchin Paracentrotus lividus. To profile the immunomodulatory function of PVP–AuNPs (0.1 μg mL−1) in sea urchin immune cells stimulated by Vibrio (10 μg mL−1) for 3 h, we focused on the baseline immunological state of the donor, and we analysed the topography, cellular metabolism, and expression of human cell surface antigens of the exposed cells, as well as the signalling leading the interaction between PVP–AuNPs and the Vibrio-stimulated cells. PVP–AuNPs are not able to silence the inflammatory signalling (TLR4/p38MAPK/NF-κB signalling) that involves the whole population of P. lividus immune cells exposed to Vibrio. However, our findings emphasise the ability of PVP–AuNPs to stimulate a subset of rare cells (defined here as Group 3) that express CD45 and CD14 antigens on their surface, which are known to be involved in immune cell maturation and macrophage activation in humans. Our evidence on how PVP–AuNPs may stimulate sea urchin immune cells represents an important starting point for planning new research work on the topic.
BACKGROUND Hemangioblastomas are well vascularized, benign CNS tumors and the third most common primary spinal cord tumor after astrocytoma/ependymoma, occurring sporadically or as a part of an autosomal dominant von Hippel-Lindau disease in which tumors are often multiple and prone to relapse. Spinal hemangioblastomas are commonly located in the cervical cord and associated with a syrinx formation. Due to location and growth trends, they may cause significant neurological deficit, impairing patient quality of life. We conducted a systematic review to understand better clinical insights of spinal hemangioblastoma in adults and compare spinal hemangioblastoma versus posterior cranial fossa hemangioblastoma. METHODS Followed PRISMA guidelines for conducting systematic reviews, we performed a review of the English literature on adult spinal hemangioblastoma in the MEDLINE/PubMed database over the last 40 years. RESULTS We reviewed 237 total scientific articles on adult spinal hemangioblastoma and analyzed national and continental distribution, clinical symptomatology, tumor location and presence of syringomyelia, treatment strategies and postoperative complications, histology and immunochemistry, as well as treatment outcomes. We also compared individual characteristics in both sporadic and von Hippel-Lindau Disease spinal hemangioblastomas. Finally, we compared features of posterior cranial fossa and spinal hemangioblastomas. CONCLUSION Spinal cord hemangioblastomas are most commonly located dorsally and intramedullary. Total surgical tumor resection is the first treatment option, while preoperative embolization may be performed to reduce intraoperative bleeding and surgical time. Hemangioblastomas located in the spine have decreased mortality and rate of infection, but increased rates of cardiopulmonary complications compared with those found in the posterior cranial fossa.
With an exclusive diet of hard-shelled mollusks, the black drum fish (Pogonias Cromis) exhibits one of the highest bite forces among extant animals. Here we present a systematic microstructural, chemical, crystallographic, and mechanical analysis of the black drum teeth to understand the structural basis for achieving the molluscivorous requirements. At the material level, the outermost enameloid shows higher modulus (Er = 126.9 ± 16.3 GPa, H = 5.0 ± 1.4 GPa) than other reported fish teeth, which is attributed to the stiffening effect of Zn and F doping in apatite crystals and the preferential co-alignment of crystallographic c-axes and enameloid rods along the biting direction. The high fracture toughness (Kc = 1.12 MPa•m1/2) near outer enameloid also promotes local yielding instead of fracture during crushing contact with mollusk shells. At the individual-tooth scale, the molar-like teeth, high density of dentin tubules, enlarged pulp chamber, and specialized dentin-bone connection, all contribute to the functional requirements, including confinement of contact compressive stress in the stiff enameloid, enhanced energy absorption in the compliant dentin, and controlled failure of tooth-bone composite under excessive loads. These results show that the multi-scale structures of black drum teeth are adapted to feed on mollusks. STATEMENT OF SIGNIFICANCE: : The black drum fish feeds on hard-shelled mollusks, which requires strong, tough, and wear-resistant teeth. This study presents a comprehensive multiscale material and mechanical analysis of the black drum teeth in achieving such remarkable biological function. At microscale, the fluoride- and zinc-doped apatite crystallites in the outer enameloid region are aligned perpendicular to the occlusal surface, representing as one of the stiffest biomineralized materials found in nature, while these apatite crystals are arranged into intertwisted rods with crystallographic misorientation in the inner enameloid region for increased crack resistance and toughness. At macroscale, the molariform geometry, the two-layer design based on the outer enameloid and inner dentin, enlarged pulp chamber and the underlying strong bony toothplate work synergistically to contribute to the teeth's crushing resistance.
Gold nanorods have been implicated in several biomedical applications. Herein, the effect of two surface-modified gold nanorods on the early stages of embryogenesis and angiogenesis was investigated using avian embryos at three days and their chorioallantoic membrane (CAM) at five days of incubation. We found that gold nanorods (GNR) modified with PEGylated phospholipid moiety show a high mortality rate in embryos after four days of exposure compared to GNR modified with PEGylated cholesterol moiety. Meanwhile, our data revealed that surface modified-GNR significantly inhibit the formation of new blood vessels in the treated CAM model after 48 h of exposure. Moreover, we report that surface-modified GNR significantly deregulate the expression of several genes implicated in cell proliferation, invasion, apoptosis, cellular energy metabolism, and angiogenesis. On the other hand, our data point out that GNR treatments can modulate the expression patterns of JNK1/2/3, NF-KB/p38, and MAPK, which could be the main molecular pathways of the nanorods in our experimental models.
Abstract To model fiber failures in random fiber networks, we have developed an elastoplastic Timoshenko beam finite element with embedded discontinuities. The method is based on the theory of strong discontinuities where the generalized displacement field is enhanced by a jump. The continuum mechanics formulation accounts for a fracture process zone and a bulk material while retaining traction continuity across the discontinuity. The additional degrees of freedom that are associated with the discontinuity are represented by a midpoint node, which is statically condensed to enable the implementation in commercial software through the user element interface . We propose a quasi-brittle fracture model, where the failure-related deformation is uncoupled from the plastic deformation in the bulk material. To retain the positive definite finite element stiffness matrix of the bulk material, we neglect the fracture-related softening of the discontinuity and employ a modified Newton iteration in the strain softening domain. Our implementation facilitates the integration into commercial finite element software and examples illustrate the robustness of the method. The FORTRAN source code is freely available to benchmark our model. We show that fiber failures contribute to the nonlinear stress–strain response of paper. Together with fiber–fiber bond failures, they can potentially explain the nonlinear stress–strain response of paper and nanopaper.
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