University of Szeged
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Effects of goal-directed fluid therapy on microcirculation during human study and animal experiment
Full text linkFluid resuscitation remains one of the cornerstone’s in the management of acute bleeding. According to Starling's “Three-compartment model”, four-times more crystalloids (Cryst) have the same volume-replacement (VR) effect as colloids (Coll). However, this VR ratio remains a controversial issue as it may be affected by the degradation of the endothelial glycocalyx layer (GX), a situation often found in the critically ill. On the other hand, macro- and microcirculatory effects of solutions are difficult to compare, because the endpoints of resuscitation seldom based on similar criteria.
Our aims were: (1) to compare the effects of Coll and Cryst based fluid resuscitation during an experimental stroke volume index (SVI) guided haemorrhage and resuscitation animal model; (2) to investigate the effects of Cryst and Coll’s on the microcirculation during free flap surgery when management was guided by detailed haemodynamic assessment.
In our animal experiment, anesthetized and mechanically ventilated pigs were randomised to receive Coll or Cryst infusion. Animals were bled until baseline SVI (Tbsl) dropped by 50% (T0), followed by resuscitation until initial SVI was reached (T4) in four steps. In our clinical trial patients undergoing maxillofacial tumour resection and free flap reconstruction were randomised into groups treated with either intra-operative Cryst or Coll solutions.
In the animal experiment, hemodynamic changes and GX degradation products serum levels followed similar pattern without significant difference between the groups. Animals received significantly less resuscitation fluid in the Coll as compared to the Cryst-group. In the clinical trial there was no difference between the groups regarding patient characteristics. Both groups remained haemodynamically stable throughout, but patients in the Cryst group required approximately 1.5 times more total fluid volume than in the Coll group. There was no significant difference in the microcirculatory blood flow between the groups as indicated by laser-Doppler flowmetry.
We concluded that: (1) volume-replacement ratio for solutions follows the Starling's principle when the GX is intact, and (2) when fluid management is guided by detailed haemodynamic assessment there was no difference between the effects of solutions on the microcirculation, hence it may not be the type of the fluid, but the appropriate VR caused haemodynamic stability and perfusion that is responsible for microcirculatory blood flow
Multi-faceted approach evidencing the role of a polar signaling channel in the activation mechanism of G protein-coupled receptors
Full text linkAsszembliszómák valamint a fehérjeaggregáció és a terápiarezisztencia összefüggéseinek vizsgálata emlőtumorban
Full text linkHigh-throughput imaging platform for 3-dimensional cell cultures using light-sheet microscopy
Full text linkAz elhízással összefüggő elváltozások sejtszintű és molekuláris mechanizmusainak, valamint a HSPB1 szabályozó szerepének vizsgálata diéta-indukált és transzgenikus egérmodellekben
Full text linkSalutations in intercultural academic communication: Hungarian instructors’ perceptions of im/politeness in CooSpace messages
Full text linkWritten online communication has become an important channel of interaction in higher education, especially during the COVID-19 pandemic (Domonkosi & Ludányi, 2022). In that period, face-to-face communication in universities was often replaced by digital platforms such as CooSpace at the University of Szeged, where international medical students and Hungarian instructors communicated through written messages. This also affected the way of student-instructor interaction. The objective of the study is to investigate how international students use salutations in their CooSpace messages and how their instructors perceive them in terms of im/politeness. It is framed by intercultural pragmatics (Kecskes, 2013; 2016) and im/politeness research (Brown & Levinson, 1987; Culpeper, 2011; Kádár, 2017; Locher & Watts, 2005), fields that examine how im/politeness is negotiated in communication across different linguistic and cultural backgrounds. Most previous studies concentrated on how students write emails (Codina-Espurz & Salazar-Campillo, 2019; Eslami, 2013; Ko et al., 2015). Notably, Pap (2022) investigated international students’ emails in Hungary. However, only a limited number of studies have examined instructors’ perceptions (Economidou-Kogetsidis, 2011; Pinto, 2019; Savić, 2018).
The research is based on 151 authentic CooSpace messages sent during the pandemic, together with instructors’ evaluations from a perception questionnaire (22 participants) and semi-structured interviews (13 participants). Data were analyzed using quantitative data analysis and qualitative content analysis. Through the three sources of data, the study explores what forms of salutations students use and how instructors perceive them. The findings show a wide range of variations: some students use highly formal salutations, others prefer informal or unconventional ones, and in some cases, salutations are missing altogether. Instructors evaluated these forms very differently. Titles and formal structures were usually viewed positively, while informal forms were perceived as impolite. At the same time, salutations in Hungarian, even if not perfectly appropriate, were often interpreted by the instructors as signs of cultural effort and respect. The interviews also highlighted how instructors reacted to perceived impoliteness and whether faculty-level guidelines would be helpful.
The study contributes to the field of intercultural pragmatics, specifically to the investigation and understanding of im/politeness in intercultural communication. The findings suggest potential implications for student-instructor written communication: raising students’ awareness of academic salutation norms and providing institutional guidance could support clearer and more effective communication. Future research could broaden the focus beyond salutations in academic emails, such as closings or request strategies. It could also compare instructors’ perceptions across different institutions and cultural contexts
Reforming Intermediary Copyright Liability in China: A Comparative Analysis of the U.S., EU, and China
Full text linkRemoval of Ammonium ions and Phosphates ions from aqueous solutions using biochar as an adsorbent and recovery of them as fertilizers
Full text linkIn general, domestic wastewaters contain huge amount of ammonium and phosphates which are components known to cause eutrophication, and should be removed. However, these compounds could be utilized as fertilizers too.
Biochar can remove a wide range of pollutants from water, because of this, it is important to study the physical–chemical properties to predict the behaviour of the biochar adsorbent in contact with adsorbates. Thus, this study aims to investigate the impact of the feedstock and the produce biochar conditions, additionally to determine the efficiency of biochar as an adsorbent of ammonium in aqueous solutions in the presence of organic compounds of typical dairy wastewaters and in presence of phosphates.
Banana leaves and poplar chop were the feedstock used for produce biochars samples, 300, 400 and 500 °C were the pyrolysis temperature; non-modification, alkali modification and acidic modification were the conditions for pretreat the material before pyrolysis process. The characterization of all biochars samples were carried out through zeta potential analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy (SEM–EDX), Fourier transform infrared spectroscopy, and specific surface area measurements. The adsorption properties of biochars were evaluated by Batch experiments, germination and planting experiments were performed for used the recovery biochar enhanced with nutrients.
The results demonstrated that the pyrolysis temperature has a large impact on the yield, structure, elemental composition, and surface chemistry of the biochar. Considering the non-modified condition, biochar prepared at 300 °C is the most efficient for NH4+ adsorption, achieving a capacity of 7.0 mgNH4+/g of banana-derived biochar used and 4.38 mgNH4+/mg of poplar chop biochar. Alkali modification enhanced the adsorption capacity results and acidic modification does not influence significantly in the adsorption capacity. The Temkin isotherm model fits better the experimental data of poplar chop-derived biochars. On the other hand, Harkins–Jura isotherm model fits the experimental data best for banana leaves-derived biochars samples
