Search results for "Chemical element"
showing 10 items of 32 documents
The study of neutron-rich nuclei production in the region of the closed shell N=126 in the multi-nucleon transfer reaction 136Xe+208Pb
2015
Expérience LNL/PRISMA; International audience; The unexplored area of heavy neutron rich nuclei is extremely important for nuclearastrophysics investigations and, in particular, for the understanding of the r-process ofastrophysical nucleogenesis. For the production of heavy neutron rich nuclei located along theneutron closed shell N=126 (probably the last "waiting point" in the r-process of nucleosynthesis)the low-energy multi-nucleon transfer reaction 136Xe+208Pb at Elab=870MeV was explored.Due to the stabilizing eect of the closed neutron shells in both nuclei, N=82 and N=126, andthe rather favorable proton transfer from lead to xenon, the light fragments formed in this processare well b…
Element Inputs by Litterfall to the Soil in Pine Forest Ecosystems
2006
Within the framework of the litterfall chemistry subprogram of the integrated monitoring program, litterfall was collected, and the concentrations of Ca, Mg, K, Pb, and Zn were measured during 1999–2003 at the Taurene and Rucava monitoring stations in Latvia. The results showed that at Rucava there was higher production of litterfall than at Taurene due to a higher tree density. The mean annual litterfall was 3630.42 kg/ha−1 in Rucava and 3022.11 kg/ha−1 in Taurene, with maximum production in autumn at both sites. The litterfall production among the catchments varied seasonally because length of growing period, composition of tree species, and density of snow cover. The higher Ca, Mg, and K…
A new insight into the three-dimensional architecture of the Golgi complex: Characterization of unusual structures in epididymal principal cells.
2017
Principal epididymal cells have one of the largest and more developed Golgi complex of mammalian cells. In the present study, we have used this cell as model for the study of the three-dimensional architecture of the Golgi complex of highly secretory and endocytic cells. Electron tomography demonstrated the presence in this cell type of some unknown or very unusual Golgi structures such as branched cisternae, pocket-like cisternal invaginations or tubular connections. In addition, we have used this methodology and immunoelectron microscopy to analyze the close relationship between this organelle and both the endoplasmic reticulum and microtubules, and to describe in detail how these element…
Riociguat versus sildenafil on hypoxic pulmonary vasoconstriction and ventilation/perfusion matching
2017
Introduction Current treatment with vasodilators for pulmonary hypertension associated with respiratory diseases is limited by their inhibitory effect on hypoxic pulmonary vasoconstriction (HPV) and uncoupling effects on ventilation-perfusion (V'/Q'). Hypoxia is also a well-known modulator of the nitric oxide (NO) pathway, and may therefore differentially affect the responses to phosphodiesterase 5 (PDE5) inhibitors and soluble guanylyl cyclase (sGC) stimulators. So far, the effects of the sGC stimulator riociguat on HPV have been poorly characterized. Materials and methods Contraction was recorded in pulmonary arteries (PA) in a wire myograph. Anesthetized rats were catheterized to record …
Criteria for the determination of maximal oxygen uptake in patients newly diagnosed with cancer : Baseline data from the randomized controlled trial …
2020
IntroductionMaximal oxygen uptake ([Formula: see text]) is a measure of cardiorespiratory fitness often used to monitor changes in fitness during and after treatment in cancer patients. There is, however, limited knowledge in how criteria verifying [Formula: see text] work for patients newly diagnosed with cancer. Therefore, the aim of this study was to describe the prevalence of fulfillment of typical criteria verifying [Formula: see text] and to investigate the associations between the criteria and the test leader's evaluation whether a test was performed "to exhaustion". An additional aim was to establish new cut-points within the associated criteria.MethodsFrom the Phys-Can randomized c…
Early improvement of executive test performance during antidepressant treatment predicts treatment outcome in patients with Major Depressive Disorder
2017
Executive dysfunctions frequently occur in patients with Major Depressive Disorder and have been shown to improve during effective antidepressant treatment. However, the time course of improvement and its relationship to treatment outcome is unknown. The aim of the study was to assess the test performance and clinical outcome by repetitive assessments of executive test procedures during antidepressant treatment. Executive test performance was assessed in 209 –patients with Major Depressive Disorder (mean age 39.3 ± 11.4 years) and 84 healthy controls five times in biweekly intervals from baseline to week 8. Patients were treated by a defined treatment algorithm within the early medication c…
Heavy Metals in Mollusc Shells: A Quick Method for their Detection
2015
It is known for a long time that calcified tissues secreted by aquatic or terrestrial invertebrates – such as mollusc shells – have the ability to concentrate large amounts of pollutants, in particular heavy metals. In the present paper, we have found an extremely rapid and easy procedure to qualitatively detect the putative presence of heavy metals in shells, without having to use sophisticated techniques such as Wavelength Dispersive Spectroscopy, atomic adsorption spectroscopy or ICP-MS. Our method rests on the capacity of the silver enhancement chemicals that are traditionally used in immunogold localization experiments to increase the size of heavy metal nanoparticles, whatever the che…
Mechanistic insights into the phosphoryl transfer reaction in cyclin-dependent kinase 2: a QM/MM study
2019
AbstractCyclin-dependent kinase 2 (CDK2) is an important member of the CDK family exerting its most important function in the regulation of the cell cycle. It catalyzes the transfer of the gamma phosphate group from an ATP (adenosine triphosphate) molecule to a Serine/Threonine residue of a peptide substrate. Due to the importance of this enzyme, and protein kinases in general, a detailed understanding of the reaction mechanism is desired. Thus, in this work the phosphoryl transfer reaction catalyzed by CDK2 was revisited and studied by means of hybrid quantum mechanics/molecular mechanics (QM/MM) calculations. Our results show that the base-assisted mechanism is preferred over the substrat…
The Evolution of Individuality at the Molecular and Protocellular Levels
1984
The most important bioelements (= organoelements) hydrogen, carbon, oxygen and nitrogen, are also the most abundant elements throughout the Universe besides helium, neon, and silicon (Fig, 1). In the Universe carbon is about four times as abundant as silicon. Certainly, the abundance of elements in various celestial bodies may vary greatly depending on the history of these celestial bodies.
Usual Care and Informed Consent in Clinical Trials of Oxygen Management in Extremely Premature Infants
2016
Objective The adequacy of informed consent in the Surfactant, Positive Pressure, and Pulse Oximetry Randomized Trial (SUPPORT) has been questioned. SUPPORT investigators and publishing editors, heads of government study funding agencies, and many ethicists have argued that informed consent was adequate because the two oxygen saturation target ranges studied fell within a range commonly recommended in guidelines. We sought to determine whether each oxygen target as studied in SUPPORT and four similar randomized controlled trials (RCTs) was consistent with usual care. Design/Participants/Setting PubMed, EMBASE, Web of Science, and Scopus were searched for English articles back to 1990 providi…