Authors:Ioana Mozos, M. Hancu, N. Jost, and A. Cristescu
Chronic myocardial infarction (CMI) may create, due to structural heterogeneity, abnormal electrophysiological substrates which trigger re-entrant life-threatening ventricular arrhythmias.Methods: Electrical instability is assessed using body surface mapping (BSM) [multipolar isointegral QRST maps (mp IQRST)] and 12-lead ECG (QT dispersion: QTd: the difference between maximal and minimal QT interval). The aim was to find the relation between mp IQRST and QTd in CMI patients.Results: The 32 CMI patients, underwent 12-lead ECG and 64-lead BSM. The 80% (25) of the patients had mp IQRST maps. QTd was larger in patients with mp than those with dipolar maps (dp): 170±20 ms in mp vs 94±19 ms in dp, respectively. The latter, mp IQRST was associated with a decrease of maximum and a stronger minimum.Conclusions: Multipolar IQRST is associated with a loss of maximum values and increased absolute values of the minimum in CMI patients. IQRST and QTd provide similar information in predicting postinfarction arrhythmia risk.
This paper brings together recent statistical evidence on international (co-)publications and (foreign) PhD-students and scholars
to document shifts in geographic sources of scientific production and the impact this has on flows of scientific talent and
partnering for scientific collaboration. The evidence demonstrates that despite the continued dominance of the US and the
increasing importance of the EU, the TRIAD is in relative decline. Other geographic sources of science outside the TRIAD are
rising, both in quantity, but also, although still to a lesser extent, in quality. Especially China drives this non-TRIAD
growth. This catching-up of non-TRIAD countries drives a slow but real process of global convergence. It nevertheless leaves
a less equal non-TRIAD science community, as the growth of China, is not matched by other non-TRIAD countries. Despite the
rise of China’s own scientific production, and the increasing return flows of overseas students and scholars, the outward
flows of Asian talents have not diminished over time. The data suggest a high correlation between the patterns of international
mobility of scientists and the patterns of international collaborations. The large and stable flow of Chinese human capital
into the US forms the basis on which stable international US-Chinese scientific networks are built. With the EU lacking this
Chinese human capital circulation, it is more difficult to build up similar strong and stable networks.
A globális rend kereteinek
kialakításában ma egyre nagyobb hangsúlyt kap a Kínai Népköztársaság, a világ
legnagyobb gazdaságainak egyike, egyben a Föld legnépesebb országa. Kína mára
az ázsiai–csendes-óceáni térség nagyhatalma, és növekvősúlyú világpolitikai,
globális biztonsági, valamint világgazdasági tényező lett, amely egyre inkább
hatást gyakorol a nemzetközi rendre. Ugyanakkor a kínai állam felkészültsége
nem tartott lépést e folyamatokkal: míg számos, a térséget érintőkérdés kapcsán
valóban Kína lehet a legautentikusabb dö__
Authors:S. LaMont, R. Gehrke, S. Glover, and R. Filby
There is a significant discrepancy in the reported values for the emission probability of the 186 keV gamma-ray resulting from the alpha decay of 226 Ra to 186 keV excited state of 222 Rn. Published values fall in the range of 3.28 to 3.59 gamma-rays per 100 alpha-decays. An interesting observation is that the lower value, 3.28, is based on measuring the 186 keV gamma-ray intensity relative to the 226 Ra alpha-branch to the 186 keV level. The higher values, which are close to 3.59, are based on measuring the gamma-ray intensity from mass standards of 226 Ra that are traceable to the mass standards prepared by HÓNIGSCHMID in the early 1930's. This discrepancy was resolved in this work by carefully measuring the 226 Ra alpha-branch intensities, then applying the theoretical E2 multipolarity internal conversion coefficient of 0.692±0.007 to calculate the 186 keV gamma-ray emission probability. The measured value for the alpha branch to the 186 keV excited state was (6.16±0.03)%, which gives a 186 keV gamma-ray emission probability of (3.64±0.04)%. This value is in excellent agreement with the most recently reported 186 keV gamma-ray emission probabilities determined using 226 Ra mass standards.
We investigated the dendritic patterns of rapid Golgi-impregnated, highly similar multipolar neurons from two functionally different thalamic regions of the rat brain: two dorsal nuclei (the nucleus laterodorsalis thalami, pars dorsomedialis and the nucleus laterodorsalis thalami, pars ventrolateralis), and two ventral nuclei (the nucleus ventrolateralis thalami and the nucleus ventromedialis thalami). The analysis involved conventional morphometric parameters (height and size) and a new parameter derived from graph theory, the relative imbalance (RI), derived from the branching patterns of the dendrites, which permits quantitative characterization of the dendritic arborization of a neuron. On this basis, neurons can be grouped into three fundamentally different types: type A, or highly-polarized (imbalanced) neurons (RI values close to 1); type B, or medium-polarized neurons (RI values around 0.5); and type C, or balanced neurons with low polarization (RI values close to 0). The orientations of the dendritic arbor, and thus the receptive fields, of the dorsal and ventral thalamic neurons, were mutually perpendicular. The H and S values indicated that the neurons in the dorsal and ventral thalamic nuclei differed significantly. However, their RI values demonstrated that they were similar neurons of type B. Our data reveal that 1) the dendritic arbor cannot be reliably characterized purely on the basis of height and size, and 2) RI is a valuable morphometric parameter that identifies the true nature of the dendritic arborization.
Authors:J. Takács, Roberta Zaninetti, Julianna Víg, Cs. Vastagh, and J. Hámori
We have investigated the expression of Doublecortin (Dcx) protein in the developing cerebellum of mouse from postnatal 2nd day to postnatal 22nd day and in young adults by immunohistochemistry. Strong expression of Dcx was present in the inner zone of the external granule cell layer, and remained strong while postmitotic granule cell precursors were present in this transitory layer. Descending granule cell precursors exhibited Dcx immunostaining not only while migrating but for a short time also after their settlement. Dcx-immunostained cells appeared in deep cerebellocortical territories and in the cerebellar white matter during the first postnatal week. These bipolar cells were arranged in the sagittal plane and built up transitory migratory streams during the second postnatal week and their number gradually decreased during the third postnatal week. Upward migration of bipolar cells was observed while leaving the migratory streams, penetrating the internal granule cell layer and the molecular layer. These cells were considered as precursors of late migrating molecular layer interneurons. However, a proportion of Dcx-immunostained cells underwent a bipolar-to-multipolar dendritic remodellation and — on the basis of strong morphological similarities — was taken for “multipotent progenitor cells”, described recently in the neocortex of adult rat.
Authors:K. Altdorfer, T. Zelles, É. Pongor, and Erzsébet Fehér
Lingual components of the autonomic nervous system are considered to be the most rostral portion of the enteric nervous system. Therefore our aim was to study the intrinsic nerve cell bodies and synapses using immunohisto-, immunocytochemical methods. Several small groups of ganglia with cell bodies immunoreactive (IR) for vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY) and substance P (SP) were observed just below the gustatory epithelium. A few somatostatin and galanin IR nerve cell bodies were also found. Many IR cell bodies were also demonstrated in the glands and next to blood vessels. Some of these cell bodies were multipolar and some of them were small neurons with an ovoid shape having only one process. Cell bodies positive for calcitonin gene-related peptide (CGRP) were detected neither in the superficial nor in the deep portion. Electronmicroscopical analysis demonstrated different IR nerve fibres having axo-somatic and axo-dendritic synapses with other immunonegative cells. In a few cases VIP IR nerve processes were found to synaptize with other VIP positive nerve cell bodies. These results support the existance of intralingual reflex in the tongue, where the ganglia might have an integrative role of the different neuropeptide containing nerve fibres.
Radiofrequency radiations (RFR) are electromagnetic frequencies (EMFs) that encompass frequencies below that of visible light and above that of extremely low frequency fields. Typical man-made sources of RFR include broadcast AM/FM/TV, mobile phones and base stations, microwave ovens and radar. In this investigation, the cytological and molecular effects of RF-EMFs at 2.45 GHz, the frequency commonly used in telecommunication and microwave ovens, have been investigated in dividing root cells of five wheat cultivars following grain exposure to very short times ranging from one second to one minute. Enhanced mitotic activity and increased proportion of chromosomal abnormalities were scored in root cells as the exposure time increased. Most abnormalities are comprised of cmetaphase configurations, unoriented chromosomes at metaphase, laggards and multipolar ana-telophases indicating an action on the mitotic apparatus as well as chromosomal bridges and the formation of micronuclei indicating true clastogenic effects by the used radiation. In addition, the amplified fragment length polymorphism (AFLP) fingerprinting indicated marked DNA polymorphism among wheat cultivars and also as a result of exposure to RF-EMFs at 2.45 GHz. The results indicate remarkable cytogenetic and molecular consequence of man-made sources of RFR in plants that may lead to genetic variation. However, further research on this aspect is required to get a concrete answer for its mutagenic/carcinogenic activity.
from a unipolar world, dominated by the US since the end of the Cold War, to a new multipolar order incorporating China remains axiomatically uncertain. China is in transition from being a developing nation which only decades ago was a uniformly poor