44 research outputs found
Carbon-nitrogen interactions in European forests and semi-natural vegetation - Part 1: Fluxes and budgets of carbon, nitrogen and greenhouse gases from ecosystem monitoring and modelling
The impact of atmospheric reactive nitrogen (N) deposition on carbon (C) sequestration in soils and biomass of unfertilized, natural, semi-natural and forest ecosystems has been much debated. Many previous results of this dC/dN response were based on changes in carbon stocks from periodical soil and ecosystem inventories, associated with estimates of N deposition obtained from large-scale chemical transport models. This study and a companion paper (Flechard et al., 2020) strive to reduce uncertainties of N effects on C sequestration by linking multi-annual gross and net ecosystem productivity estimates from 40 eddy covariance flux towers across Europe to local measurement-based estimates of dry and wet N deposition from a dedicated collocated monitoring network. To identify possible ecological drivers and processes affecting the interplay between C and N inputs and losses, these data were also combined with in situ flux measurements of NO, NO and CH fluxes; soil NO̅ leaching sampling; and results of soil incubation experiments for N and greenhouse gas (GHG) emissions, as well as surveys of available data from online databases and from the literature, together with forest ecosystem (BASFOR) modelling. Multi-year averages of net ecosystem productivity (NEP) in forests ranged from -70 to 826 gCm yr at total wet+dry inorganic N deposition rates (N) of 0.3 to 4.3 gNm yr and from -4 to 361 g Cm yr at N rates of 0.1 to 3.1 gNm yr in short semi-natural vegetation (moorlands, wetlands and unfertilized extensively managed grasslands). The GHG budgets of the forests were strongly dominated by CO exchange, while CH and NO exchange comprised a larger proportion of the GHG balance in short semi-natural vegetation. Uncertainties in elemental budgets were much larger for nitrogen than carbon, especially at sites with elevated N where N leaching losses were also very large, and compounded by the lack of reliable data on organic nitrogen and N losses by denitrification. Nitrogen losses in the form of NO, NO and especially NO̅ were on average 27%(range 6 %–54 %) of N at sites with N 3 gNm yr. Such large levels of N loss likely indicate that different stages of N saturation occurred at a number of sites. The joint analysis of the C and N budgets provided further hints that N saturation could be detected in altered patterns of forest growth. Net ecosystem productivity increased with N deposition up to 2–2.5 gNm yr, with large scatter associated with a wide range in carbon sequestration efficiency (CSE, defined as the NEP = GPP ratio). At elevated N levels (> 2.5 gNm yr), where inorganic N losses were also increasingly large, NEP levelled off and then decreased. The apparent increase in NEP at low to intermediate N levels was partly the result of geographical cross-correlations between N and climate, indicating that the actual mean dC/dN response at individual sites was significantly lower than would be suggested by a simple, straightforward regression of NEP vs. N
Mechanisms of pulmonary edema in sheep exposed to FAE charge: J.Trauma
NRC publication: Ye
Difficulties in preventing repeated genital self-mutilation
© 2016, University of Kragujevac, Faculty of Science. All rights reserved. Self-mutilation is self-inflicted and intentional damage done to one’s body or one’s body parts without a conscious suicidal intention. The first case of genital self-mutilation was published in 1846, and the first scientific description of genital self-mutilation was written by Stroch in 1901. Since the first case has been described, there have been a relatively small number of described cases of genital self-mutilation in both genders; there have been an even smaller number of cases of repeated genital self-mutilation and only a few descriptions of repetitive forms of male genital self-mutilation in the literature. The aim of our study is to present difficulties in preventing repeated male genital self-mutilation of a patient with an intellectual disability who was diagnosed and treated for epilepsy and psychosis in early adult life and had a previous history of self-destructive behaviour during childhood. Previous literature does not contain many repeated cases of male genital self-mutilation. After evaluating the contribution of each individual factor in the aetiology of self-mutilation, we concluded that every individual factor is significant in the aetiology of selfmutilation; however, no single factor, as well as all the factors put together, is not enough for prevention of self-mutilation. Our conclusion is that all the presented factors in our research (intellectual disability, epilepsy, psychosis, self-destructive tendencies in childhood) have their place in the aetiology of male genital selfmutilation, but none of them are determining factors. This confirms that it is necessary to conduct further research in the field of aetiology of male genital self-mutilation, which would contribute towards more adequate prevention
Otopalatodigital syndrome type I: novel characteristics and prenatal manifestations in two siblings
Otopalatodigital spectrum disorder (OPDSD) is rare group of X-linked disorders caused by mutations in the filamin A (FLNA) gene. It is characterized by skeletal dysplasia of variable severity and different extra skeletal manifestations. Its presentation in the fetal period is quite unspecific, so diagnosis is usually made after birth. We present prenatal ultrasonography and postmortem findings that led us to a diagnosis of the mildest form of OPDSD (OPD type I) in two consecutive pregnancies. This is the first report on prenatal diagnosis (PND) of OPD type I. Affected fetuses showed facial dysmorphy (hypertelorism, micrognathia, cleft palate) and digital anomalies, features typical of OPD type I. In addition, microphtalmia and early neonatal death due to severe respiratory distress syndrome are described as a novel characteristics of the disorder. Clinical exome sequencing revealed a hemizygous missense pathogenic variant in the FLNA gene (NM_ 001110556.1: c.620C>T). We suggest that the presence of hypertelorism, micrognathia, digital anomalies on prenatal ultrasound examination should alert suspicion to OPDSD. Detailed clinical examination of mother and other female relatives is of great importance in establishing definitive diagnosis of OPD type I
Attitudes of medical and pharmacy students towards patients suffering from schizophrenia
© 2017, University of Kragujevac, Faculty of Science. All rights reserved. Research over the past twenty years has shown that the attitudes of health care workers and students towards people who are suffering from schizophrenia have become more negative. The aim of our study was to investigate the attitudes of medical and pharmacy students towards patients with schizophrenia and explore the differences in attitudes between study groups and students in different years. Materials and methods: Second- and fifth-year medical and pharmacy students from the Faculty of Medical Sciences at the University of Kragujevac were included in an observational, prospective, cross-sectional study. The sample consisted of 113 students from the pharmacy and medical schools who were chosen via random sampling. The students completed a two-part questionnaire. The first part contained questions about sociodemographic characteristics, whereas the second part was a translated version of the Mental Illness: Clinician’s Attitudes (MICA) v4 scale. Results: There is a statistically significant difference (р<0.05) in the attitudes towards people with schizophrenia between second- and fifth-year medical and pharmacy students (with lower scores in both groups in fifth-year students). Of the total number of students who had lower summed scores on the Likert scale, 51.3% had previously finished medical high school, whereas 28.3% had previously finished regular high school. Conclusion: Our results showed a statistically significant difference in attitudes towards people with schizophrenia between second- and fifth-year students as well as a difference related to previous high school education. This stresses the importance of levels of knowledge about schizophrenia to reducing the stigmatization of patients who suffer from this disorder
European scale application of atmospheric reactive nitrogen measurements in a low-cost approach to infer dry deposition fluxes.
A European scale network was established in 2006 as part of the NitroEurope Integrated Project to infer reactive nitrogen (Nr) dry deposition fluxes, based on low-cost sampling of gaseous and aerosol species and inferential modelling. The network provides monthly measurements of NH3,
NH4+, HNO3 and NO3-, as well as SO2, SO42 , HCl, Cl- and base cations at 58 sites.
Measurements are made with an established low-cost denuder methodology (DELTA) as a basis to: 1) examine temporal trends and spatial patterns across Europe, 2) improve and calibrate inferential modelling techniques to estimate exchange of Nr species, 3) provide best estimates of
atmospheric dry N deposition, and 4) permit an analysis of net GHG exchange in relation to atmospheric and agricultural N inputs at the European scale. Responsibility for measurements is shared between seven European laboratories. An inter-comparison of the DELTA implementation by 6 laboratories at 4 test sites (Montelibretti, Italy; Braunschweig, Germany; Paterna, Spain and Auchencorth, UK) from July to October 2006 provided training for the laboratories and showed that
good agreement was achieved in different climatic conditions (87% of laboratory site means within
20% of the inter-laboratory median). Results obtained from the first year of measurements show substantial spatial variability in atmospheric Nr concentrations, illustrating the major local (NH3)and regional (HNO3, NO3-, NH4+) differences in Nr concentrations. These results provide the
basis to develop future estimates of site-based Nr dry deposition fluxes across Europe, and highlight the role of NH3, largely of agricultural origin, which was the largest single constituent and will dominate dry Nr fluxes at most sites
Appositional enamel growth in molars of South African fossil hominids
Enamel is formed incrementally by the secretory activity of ameloblast cells. Variable stages of secretion result in the formation of structures known as cross striations along enamel prisms, for which experimental data demonstrate a correspondence with daily periods of secretion. Patterns of variation in this daily growth are important to understanding mechanisms of tooth formation and the development of enamel thickness. Transmitted light microscopy (TLM) of histological ground sections and scanning electron microscopy (SEM) of bulk specimens or their surface replicas are the usual methods for investigating cross striations. However, these methods pose some constraints on the study of these features in Plio-Pleistocene hominid enamel, the specimens of which may only rarely be sectioned for TLM or examined on only their most superficial surfaces for SEM. The recent development of portable confocal scanning optical microscopy (PCSOM) resolves some of the restrictions on fractured enamel surfaces, allowing the visualization of cross striations by direct examination. This technology has been applied here to the study of Australopithecus africanus and Paranthropus robustus hominid molars from the Plio-Pleistocene of South Africa. We hypothesize that these taxa have increased enamel appositional rates compared with modern humans, because despite having thicker enamelled molars (particularly P. robustus), the enamel crowns of these fossil taxa take an equivalent or reduced amount of time to form. Cross striations were measured in cuspal, lateral and cervical regions of the enamel crowns, and, within each region, the inner, middle and outer zones. Values obtained for A. africanus outer zones of the enamel crown are, in general, lower than those for P. robustus, indicating faster forming enamel in the latter, while both taxa show higher rates of enamel growth than modern humans and the African great apes. This demonstrates a relatively high degree of variability in the mechanisms underlying the development of enamel across taxa